Bug Summary

File:llvm/lib/Analysis/ConstantFolding.cpp
Warning:line 2561, column 35
Called C++ object pointer is null

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clang -cc1 -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name ConstantFolding.cpp -analyzer-store=region -analyzer-opt-analyze-nested-blocks -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -analyzer-config-compatibility-mode=true -mrelocation-model pic -pic-level 2 -mframe-pointer=none -fmath-errno -fno-rounding-math -mconstructor-aliases -munwind-tables -target-cpu x86-64 -tune-cpu generic -fno-split-dwarf-inlining -debugger-tuning=gdb -ffunction-sections -fdata-sections -resource-dir /usr/lib/llvm-12/lib/clang/12.0.0 -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I /build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/build-llvm/lib/Analysis -I /build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/lib/Analysis -I /build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/build-llvm/include -I /build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/include -U NDEBUG -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/x86_64-linux-gnu/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/x86_64-linux-gnu/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0/backward -internal-isystem /usr/local/include -internal-isystem /usr/lib/llvm-12/lib/clang/12.0.0/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -O2 -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -Wno-maybe-uninitialized -Wno-comment -std=c++14 -fdeprecated-macro -fdebug-compilation-dir /build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/build-llvm/lib/Analysis -fdebug-prefix-map=/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b=. -ferror-limit 19 -fvisibility-inlines-hidden -stack-protector 2 -fgnuc-version=4.2.1 -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -faddrsig -o /tmp/scan-build-2020-09-17-195756-12974-1 -x c++ /build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/lib/Analysis/ConstantFolding.cpp

/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/lib/Analysis/ConstantFolding.cpp

1//===-- ConstantFolding.cpp - Fold instructions into constants ------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file defines routines for folding instructions into constants.
10//
11// Also, to supplement the basic IR ConstantExpr simplifications,
12// this file defines some additional folding routines that can make use of
13// DataLayout information. These functions cannot go in IR due to library
14// dependency issues.
15//
16//===----------------------------------------------------------------------===//
17
18#include "llvm/Analysis/ConstantFolding.h"
19#include "llvm/ADT/APFloat.h"
20#include "llvm/ADT/APInt.h"
21#include "llvm/ADT/APSInt.h"
22#include "llvm/ADT/ArrayRef.h"
23#include "llvm/ADT/DenseMap.h"
24#include "llvm/ADT/STLExtras.h"
25#include "llvm/ADT/SmallVector.h"
26#include "llvm/ADT/StringRef.h"
27#include "llvm/Analysis/TargetFolder.h"
28#include "llvm/Analysis/TargetLibraryInfo.h"
29#include "llvm/Analysis/ValueTracking.h"
30#include "llvm/Analysis/VectorUtils.h"
31#include "llvm/Config/config.h"
32#include "llvm/IR/Constant.h"
33#include "llvm/IR/Constants.h"
34#include "llvm/IR/DataLayout.h"
35#include "llvm/IR/DerivedTypes.h"
36#include "llvm/IR/Function.h"
37#include "llvm/IR/GlobalValue.h"
38#include "llvm/IR/GlobalVariable.h"
39#include "llvm/IR/InstrTypes.h"
40#include "llvm/IR/Instruction.h"
41#include "llvm/IR/Instructions.h"
42#include "llvm/IR/IntrinsicInst.h"
43#include "llvm/IR/Intrinsics.h"
44#include "llvm/IR/IntrinsicsAMDGPU.h"
45#include "llvm/IR/IntrinsicsARM.h"
46#include "llvm/IR/IntrinsicsWebAssembly.h"
47#include "llvm/IR/IntrinsicsX86.h"
48#include "llvm/IR/Operator.h"
49#include "llvm/IR/Type.h"
50#include "llvm/IR/Value.h"
51#include "llvm/Support/Casting.h"
52#include "llvm/Support/ErrorHandling.h"
53#include "llvm/Support/KnownBits.h"
54#include "llvm/Support/MathExtras.h"
55#include <cassert>
56#include <cerrno>
57#include <cfenv>
58#include <cmath>
59#include <cstddef>
60#include <cstdint>
61
62using namespace llvm;
63
64namespace {
65
66//===----------------------------------------------------------------------===//
67// Constant Folding internal helper functions
68//===----------------------------------------------------------------------===//
69
70static Constant *foldConstVectorToAPInt(APInt &Result, Type *DestTy,
71 Constant *C, Type *SrcEltTy,
72 unsigned NumSrcElts,
73 const DataLayout &DL) {
74 // Now that we know that the input value is a vector of integers, just shift
75 // and insert them into our result.
76 unsigned BitShift = DL.getTypeSizeInBits(SrcEltTy);
77 for (unsigned i = 0; i != NumSrcElts; ++i) {
78 Constant *Element;
79 if (DL.isLittleEndian())
80 Element = C->getAggregateElement(NumSrcElts - i - 1);
81 else
82 Element = C->getAggregateElement(i);
83
84 if (Element && isa<UndefValue>(Element)) {
85 Result <<= BitShift;
86 continue;
87 }
88
89 auto *ElementCI = dyn_cast_or_null<ConstantInt>(Element);
90 if (!ElementCI)
91 return ConstantExpr::getBitCast(C, DestTy);
92
93 Result <<= BitShift;
94 Result |= ElementCI->getValue().zextOrSelf(Result.getBitWidth());
95 }
96
97 return nullptr;
98}
99
100/// Constant fold bitcast, symbolically evaluating it with DataLayout.
101/// This always returns a non-null constant, but it may be a
102/// ConstantExpr if unfoldable.
103Constant *FoldBitCast(Constant *C, Type *DestTy, const DataLayout &DL) {
104 assert(CastInst::castIsValid(Instruction::BitCast, C, DestTy) &&((CastInst::castIsValid(Instruction::BitCast, C, DestTy) &&
"Invalid constantexpr bitcast!") ? static_cast<void> (
0) : __assert_fail ("CastInst::castIsValid(Instruction::BitCast, C, DestTy) && \"Invalid constantexpr bitcast!\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/lib/Analysis/ConstantFolding.cpp"
, 105, __PRETTY_FUNCTION__))
105 "Invalid constantexpr bitcast!")((CastInst::castIsValid(Instruction::BitCast, C, DestTy) &&
"Invalid constantexpr bitcast!") ? static_cast<void> (
0) : __assert_fail ("CastInst::castIsValid(Instruction::BitCast, C, DestTy) && \"Invalid constantexpr bitcast!\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/lib/Analysis/ConstantFolding.cpp"
, 105, __PRETTY_FUNCTION__))
;
106
107 // Catch the obvious splat cases.
108 if (C->isNullValue() && !DestTy->isX86_MMXTy())
109 return Constant::getNullValue(DestTy);
110 if (C->isAllOnesValue() && !DestTy->isX86_MMXTy() &&
111 !DestTy->isPtrOrPtrVectorTy()) // Don't get ones for ptr types!
112 return Constant::getAllOnesValue(DestTy);
113
114 if (auto *VTy = dyn_cast<VectorType>(C->getType())) {
115 // Handle a vector->scalar integer/fp cast.
116 if (isa<IntegerType>(DestTy) || DestTy->isFloatingPointTy()) {
117 unsigned NumSrcElts = cast<FixedVectorType>(VTy)->getNumElements();
118 Type *SrcEltTy = VTy->getElementType();
119
120 // If the vector is a vector of floating point, convert it to vector of int
121 // to simplify things.
122 if (SrcEltTy->isFloatingPointTy()) {
123 unsigned FPWidth = SrcEltTy->getPrimitiveSizeInBits();
124 auto *SrcIVTy = FixedVectorType::get(
125 IntegerType::get(C->getContext(), FPWidth), NumSrcElts);
126 // Ask IR to do the conversion now that #elts line up.
127 C = ConstantExpr::getBitCast(C, SrcIVTy);
128 }
129
130 APInt Result(DL.getTypeSizeInBits(DestTy), 0);
131 if (Constant *CE = foldConstVectorToAPInt(Result, DestTy, C,
132 SrcEltTy, NumSrcElts, DL))
133 return CE;
134
135 if (isa<IntegerType>(DestTy))
136 return ConstantInt::get(DestTy, Result);
137
138 APFloat FP(DestTy->getFltSemantics(), Result);
139 return ConstantFP::get(DestTy->getContext(), FP);
140 }
141 }
142
143 // The code below only handles casts to vectors currently.
144 auto *DestVTy = dyn_cast<VectorType>(DestTy);
145 if (!DestVTy)
146 return ConstantExpr::getBitCast(C, DestTy);
147
148 // If this is a scalar -> vector cast, convert the input into a <1 x scalar>
149 // vector so the code below can handle it uniformly.
150 if (isa<ConstantFP>(C) || isa<ConstantInt>(C)) {
151 Constant *Ops = C; // don't take the address of C!
152 return FoldBitCast(ConstantVector::get(Ops), DestTy, DL);
153 }
154
155 // If this is a bitcast from constant vector -> vector, fold it.
156 if (!isa<ConstantDataVector>(C) && !isa<ConstantVector>(C))
157 return ConstantExpr::getBitCast(C, DestTy);
158
159 // If the element types match, IR can fold it.
160 unsigned NumDstElt = cast<FixedVectorType>(DestVTy)->getNumElements();
161 unsigned NumSrcElt = cast<FixedVectorType>(C->getType())->getNumElements();
162 if (NumDstElt == NumSrcElt)
163 return ConstantExpr::getBitCast(C, DestTy);
164
165 Type *SrcEltTy = cast<VectorType>(C->getType())->getElementType();
166 Type *DstEltTy = DestVTy->getElementType();
167
168 // Otherwise, we're changing the number of elements in a vector, which
169 // requires endianness information to do the right thing. For example,
170 // bitcast (<2 x i64> <i64 0, i64 1> to <4 x i32>)
171 // folds to (little endian):
172 // <4 x i32> <i32 0, i32 0, i32 1, i32 0>
173 // and to (big endian):
174 // <4 x i32> <i32 0, i32 0, i32 0, i32 1>
175
176 // First thing is first. We only want to think about integer here, so if
177 // we have something in FP form, recast it as integer.
178 if (DstEltTy->isFloatingPointTy()) {
179 // Fold to an vector of integers with same size as our FP type.
180 unsigned FPWidth = DstEltTy->getPrimitiveSizeInBits();
181 auto *DestIVTy = FixedVectorType::get(
182 IntegerType::get(C->getContext(), FPWidth), NumDstElt);
183 // Recursively handle this integer conversion, if possible.
184 C = FoldBitCast(C, DestIVTy, DL);
185
186 // Finally, IR can handle this now that #elts line up.
187 return ConstantExpr::getBitCast(C, DestTy);
188 }
189
190 // Okay, we know the destination is integer, if the input is FP, convert
191 // it to integer first.
192 if (SrcEltTy->isFloatingPointTy()) {
193 unsigned FPWidth = SrcEltTy->getPrimitiveSizeInBits();
194 auto *SrcIVTy = FixedVectorType::get(
195 IntegerType::get(C->getContext(), FPWidth), NumSrcElt);
196 // Ask IR to do the conversion now that #elts line up.
197 C = ConstantExpr::getBitCast(C, SrcIVTy);
198 // If IR wasn't able to fold it, bail out.
199 if (!isa<ConstantVector>(C) && // FIXME: Remove ConstantVector.
200 !isa<ConstantDataVector>(C))
201 return C;
202 }
203
204 // Now we know that the input and output vectors are both integer vectors
205 // of the same size, and that their #elements is not the same. Do the
206 // conversion here, which depends on whether the input or output has
207 // more elements.
208 bool isLittleEndian = DL.isLittleEndian();
209
210 SmallVector<Constant*, 32> Result;
211 if (NumDstElt < NumSrcElt) {
212 // Handle: bitcast (<4 x i32> <i32 0, i32 1, i32 2, i32 3> to <2 x i64>)
213 Constant *Zero = Constant::getNullValue(DstEltTy);
214 unsigned Ratio = NumSrcElt/NumDstElt;
215 unsigned SrcBitSize = SrcEltTy->getPrimitiveSizeInBits();
216 unsigned SrcElt = 0;
217 for (unsigned i = 0; i != NumDstElt; ++i) {
218 // Build each element of the result.
219 Constant *Elt = Zero;
220 unsigned ShiftAmt = isLittleEndian ? 0 : SrcBitSize*(Ratio-1);
221 for (unsigned j = 0; j != Ratio; ++j) {
222 Constant *Src = C->getAggregateElement(SrcElt++);
223 if (Src && isa<UndefValue>(Src))
224 Src = Constant::getNullValue(
225 cast<VectorType>(C->getType())->getElementType());
226 else
227 Src = dyn_cast_or_null<ConstantInt>(Src);
228 if (!Src) // Reject constantexpr elements.
229 return ConstantExpr::getBitCast(C, DestTy);
230
231 // Zero extend the element to the right size.
232 Src = ConstantExpr::getZExt(Src, Elt->getType());
233
234 // Shift it to the right place, depending on endianness.
235 Src = ConstantExpr::getShl(Src,
236 ConstantInt::get(Src->getType(), ShiftAmt));
237 ShiftAmt += isLittleEndian ? SrcBitSize : -SrcBitSize;
238
239 // Mix it in.
240 Elt = ConstantExpr::getOr(Elt, Src);
241 }
242 Result.push_back(Elt);
243 }
244 return ConstantVector::get(Result);
245 }
246
247 // Handle: bitcast (<2 x i64> <i64 0, i64 1> to <4 x i32>)
248 unsigned Ratio = NumDstElt/NumSrcElt;
249 unsigned DstBitSize = DL.getTypeSizeInBits(DstEltTy);
250
251 // Loop over each source value, expanding into multiple results.
252 for (unsigned i = 0; i != NumSrcElt; ++i) {
253 auto *Element = C->getAggregateElement(i);
254
255 if (!Element) // Reject constantexpr elements.
256 return ConstantExpr::getBitCast(C, DestTy);
257
258 if (isa<UndefValue>(Element)) {
259 // Correctly Propagate undef values.
260 Result.append(Ratio, UndefValue::get(DstEltTy));
261 continue;
262 }
263
264 auto *Src = dyn_cast<ConstantInt>(Element);
265 if (!Src)
266 return ConstantExpr::getBitCast(C, DestTy);
267
268 unsigned ShiftAmt = isLittleEndian ? 0 : DstBitSize*(Ratio-1);
269 for (unsigned j = 0; j != Ratio; ++j) {
270 // Shift the piece of the value into the right place, depending on
271 // endianness.
272 Constant *Elt = ConstantExpr::getLShr(Src,
273 ConstantInt::get(Src->getType(), ShiftAmt));
274 ShiftAmt += isLittleEndian ? DstBitSize : -DstBitSize;
275
276 // Truncate the element to an integer with the same pointer size and
277 // convert the element back to a pointer using a inttoptr.
278 if (DstEltTy->isPointerTy()) {
279 IntegerType *DstIntTy = Type::getIntNTy(C->getContext(), DstBitSize);
280 Constant *CE = ConstantExpr::getTrunc(Elt, DstIntTy);
281 Result.push_back(ConstantExpr::getIntToPtr(CE, DstEltTy));
282 continue;
283 }
284
285 // Truncate and remember this piece.
286 Result.push_back(ConstantExpr::getTrunc(Elt, DstEltTy));
287 }
288 }
289
290 return ConstantVector::get(Result);
291}
292
293} // end anonymous namespace
294
295/// If this constant is a constant offset from a global, return the global and
296/// the constant. Because of constantexprs, this function is recursive.
297bool llvm::IsConstantOffsetFromGlobal(Constant *C, GlobalValue *&GV,
298 APInt &Offset, const DataLayout &DL) {
299 // Trivial case, constant is the global.
300 if ((GV = dyn_cast<GlobalValue>(C))) {
301 unsigned BitWidth = DL.getIndexTypeSizeInBits(GV->getType());
302 Offset = APInt(BitWidth, 0);
303 return true;
304 }
305
306 // Otherwise, if this isn't a constant expr, bail out.
307 auto *CE = dyn_cast<ConstantExpr>(C);
308 if (!CE) return false;
309
310 // Look through ptr->int and ptr->ptr casts.
311 if (CE->getOpcode() == Instruction::PtrToInt ||
312 CE->getOpcode() == Instruction::BitCast)
313 return IsConstantOffsetFromGlobal(CE->getOperand(0), GV, Offset, DL);
314
315 // i32* getelementptr ([5 x i32]* @a, i32 0, i32 5)
316 auto *GEP = dyn_cast<GEPOperator>(CE);
317 if (!GEP)
318 return false;
319
320 unsigned BitWidth = DL.getIndexTypeSizeInBits(GEP->getType());
321 APInt TmpOffset(BitWidth, 0);
322
323 // If the base isn't a global+constant, we aren't either.
324 if (!IsConstantOffsetFromGlobal(CE->getOperand(0), GV, TmpOffset, DL))
325 return false;
326
327 // Otherwise, add any offset that our operands provide.
328 if (!GEP->accumulateConstantOffset(DL, TmpOffset))
329 return false;
330
331 Offset = TmpOffset;
332 return true;
333}
334
335Constant *llvm::ConstantFoldLoadThroughBitcast(Constant *C, Type *DestTy,
336 const DataLayout &DL) {
337 do {
338 Type *SrcTy = C->getType();
339 uint64_t DestSize = DL.getTypeSizeInBits(DestTy);
340 uint64_t SrcSize = DL.getTypeSizeInBits(SrcTy);
341 if (SrcSize < DestSize)
342 return nullptr;
343
344 // Catch the obvious splat cases (since all-zeros can coerce non-integral
345 // pointers legally).
346 if (C->isNullValue() && !DestTy->isX86_MMXTy())
347 return Constant::getNullValue(DestTy);
348 if (C->isAllOnesValue() &&
349 (DestTy->isIntegerTy() || DestTy->isFloatingPointTy() ||
350 DestTy->isVectorTy()) &&
351 !DestTy->isX86_MMXTy() && !DestTy->isPtrOrPtrVectorTy())
352 // Get ones when the input is trivial, but
353 // only for supported types inside getAllOnesValue.
354 return Constant::getAllOnesValue(DestTy);
355
356 // If the type sizes are the same and a cast is legal, just directly
357 // cast the constant.
358 // But be careful not to coerce non-integral pointers illegally.
359 if (SrcSize == DestSize &&
360 DL.isNonIntegralPointerType(SrcTy->getScalarType()) ==
361 DL.isNonIntegralPointerType(DestTy->getScalarType())) {
362 Instruction::CastOps Cast = Instruction::BitCast;
363 // If we are going from a pointer to int or vice versa, we spell the cast
364 // differently.
365 if (SrcTy->isIntegerTy() && DestTy->isPointerTy())
366 Cast = Instruction::IntToPtr;
367 else if (SrcTy->isPointerTy() && DestTy->isIntegerTy())
368 Cast = Instruction::PtrToInt;
369
370 if (CastInst::castIsValid(Cast, C, DestTy))
371 return ConstantExpr::getCast(Cast, C, DestTy);
372 }
373
374 // If this isn't an aggregate type, there is nothing we can do to drill down
375 // and find a bitcastable constant.
376 if (!SrcTy->isAggregateType())
377 return nullptr;
378
379 // We're simulating a load through a pointer that was bitcast to point to
380 // a different type, so we can try to walk down through the initial
381 // elements of an aggregate to see if some part of the aggregate is
382 // castable to implement the "load" semantic model.
383 if (SrcTy->isStructTy()) {
384 // Struct types might have leading zero-length elements like [0 x i32],
385 // which are certainly not what we are looking for, so skip them.
386 unsigned Elem = 0;
387 Constant *ElemC;
388 do {
389 ElemC = C->getAggregateElement(Elem++);
390 } while (ElemC && DL.getTypeSizeInBits(ElemC->getType()).isZero());
391 C = ElemC;
392 } else {
393 C = C->getAggregateElement(0u);
394 }
395 } while (C);
396
397 return nullptr;
398}
399
400namespace {
401
402/// Recursive helper to read bits out of global. C is the constant being copied
403/// out of. ByteOffset is an offset into C. CurPtr is the pointer to copy
404/// results into and BytesLeft is the number of bytes left in
405/// the CurPtr buffer. DL is the DataLayout.
406bool ReadDataFromGlobal(Constant *C, uint64_t ByteOffset, unsigned char *CurPtr,
407 unsigned BytesLeft, const DataLayout &DL) {
408 assert(ByteOffset <= DL.getTypeAllocSize(C->getType()) &&((ByteOffset <= DL.getTypeAllocSize(C->getType()) &&
"Out of range access") ? static_cast<void> (0) : __assert_fail
("ByteOffset <= DL.getTypeAllocSize(C->getType()) && \"Out of range access\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/lib/Analysis/ConstantFolding.cpp"
, 409, __PRETTY_FUNCTION__))
409 "Out of range access")((ByteOffset <= DL.getTypeAllocSize(C->getType()) &&
"Out of range access") ? static_cast<void> (0) : __assert_fail
("ByteOffset <= DL.getTypeAllocSize(C->getType()) && \"Out of range access\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/lib/Analysis/ConstantFolding.cpp"
, 409, __PRETTY_FUNCTION__))
;
410
411 // If this element is zero or undefined, we can just return since *CurPtr is
412 // zero initialized.
413 if (isa<ConstantAggregateZero>(C) || isa<UndefValue>(C))
414 return true;
415
416 if (auto *CI = dyn_cast<ConstantInt>(C)) {
417 if (CI->getBitWidth() > 64 ||
418 (CI->getBitWidth() & 7) != 0)
419 return false;
420
421 uint64_t Val = CI->getZExtValue();
422 unsigned IntBytes = unsigned(CI->getBitWidth()/8);
423
424 for (unsigned i = 0; i != BytesLeft && ByteOffset != IntBytes; ++i) {
425 int n = ByteOffset;
426 if (!DL.isLittleEndian())
427 n = IntBytes - n - 1;
428 CurPtr[i] = (unsigned char)(Val >> (n * 8));
429 ++ByteOffset;
430 }
431 return true;
432 }
433
434 if (auto *CFP = dyn_cast<ConstantFP>(C)) {
435 if (CFP->getType()->isDoubleTy()) {
436 C = FoldBitCast(C, Type::getInt64Ty(C->getContext()), DL);
437 return ReadDataFromGlobal(C, ByteOffset, CurPtr, BytesLeft, DL);
438 }
439 if (CFP->getType()->isFloatTy()){
440 C = FoldBitCast(C, Type::getInt32Ty(C->getContext()), DL);
441 return ReadDataFromGlobal(C, ByteOffset, CurPtr, BytesLeft, DL);
442 }
443 if (CFP->getType()->isHalfTy()){
444 C = FoldBitCast(C, Type::getInt16Ty(C->getContext()), DL);
445 return ReadDataFromGlobal(C, ByteOffset, CurPtr, BytesLeft, DL);
446 }
447 return false;
448 }
449
450 if (auto *CS = dyn_cast<ConstantStruct>(C)) {
451 const StructLayout *SL = DL.getStructLayout(CS->getType());
452 unsigned Index = SL->getElementContainingOffset(ByteOffset);
453 uint64_t CurEltOffset = SL->getElementOffset(Index);
454 ByteOffset -= CurEltOffset;
455
456 while (true) {
457 // If the element access is to the element itself and not to tail padding,
458 // read the bytes from the element.
459 uint64_t EltSize = DL.getTypeAllocSize(CS->getOperand(Index)->getType());
460
461 if (ByteOffset < EltSize &&
462 !ReadDataFromGlobal(CS->getOperand(Index), ByteOffset, CurPtr,
463 BytesLeft, DL))
464 return false;
465
466 ++Index;
467
468 // Check to see if we read from the last struct element, if so we're done.
469 if (Index == CS->getType()->getNumElements())
470 return true;
471
472 // If we read all of the bytes we needed from this element we're done.
473 uint64_t NextEltOffset = SL->getElementOffset(Index);
474
475 if (BytesLeft <= NextEltOffset - CurEltOffset - ByteOffset)
476 return true;
477
478 // Move to the next element of the struct.
479 CurPtr += NextEltOffset - CurEltOffset - ByteOffset;
480 BytesLeft -= NextEltOffset - CurEltOffset - ByteOffset;
481 ByteOffset = 0;
482 CurEltOffset = NextEltOffset;
483 }
484 // not reached.
485 }
486
487 if (isa<ConstantArray>(C) || isa<ConstantVector>(C) ||
488 isa<ConstantDataSequential>(C)) {
489 uint64_t NumElts;
490 Type *EltTy;
491 if (auto *AT = dyn_cast<ArrayType>(C->getType())) {
492 NumElts = AT->getNumElements();
493 EltTy = AT->getElementType();
494 } else {
495 NumElts = cast<FixedVectorType>(C->getType())->getNumElements();
496 EltTy = cast<FixedVectorType>(C->getType())->getElementType();
497 }
498 uint64_t EltSize = DL.getTypeAllocSize(EltTy);
499 uint64_t Index = ByteOffset / EltSize;
500 uint64_t Offset = ByteOffset - Index * EltSize;
501
502 for (; Index != NumElts; ++Index) {
503 if (!ReadDataFromGlobal(C->getAggregateElement(Index), Offset, CurPtr,
504 BytesLeft, DL))
505 return false;
506
507 uint64_t BytesWritten = EltSize - Offset;
508 assert(BytesWritten <= EltSize && "Not indexing into this element?")((BytesWritten <= EltSize && "Not indexing into this element?"
) ? static_cast<void> (0) : __assert_fail ("BytesWritten <= EltSize && \"Not indexing into this element?\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/lib/Analysis/ConstantFolding.cpp"
, 508, __PRETTY_FUNCTION__))
;
509 if (BytesWritten >= BytesLeft)
510 return true;
511
512 Offset = 0;
513 BytesLeft -= BytesWritten;
514 CurPtr += BytesWritten;
515 }
516 return true;
517 }
518
519 if (auto *CE = dyn_cast<ConstantExpr>(C)) {
520 if (CE->getOpcode() == Instruction::IntToPtr &&
521 CE->getOperand(0)->getType() == DL.getIntPtrType(CE->getType())) {
522 return ReadDataFromGlobal(CE->getOperand(0), ByteOffset, CurPtr,
523 BytesLeft, DL);
524 }
525 }
526
527 // Otherwise, unknown initializer type.
528 return false;
529}
530
531Constant *FoldReinterpretLoadFromConstPtr(Constant *C, Type *LoadTy,
532 const DataLayout &DL) {
533 // Bail out early. Not expect to load from scalable global variable.
534 if (isa<ScalableVectorType>(LoadTy))
535 return nullptr;
536
537 auto *PTy = cast<PointerType>(C->getType());
538 auto *IntType = dyn_cast<IntegerType>(LoadTy);
539
540 // If this isn't an integer load we can't fold it directly.
541 if (!IntType) {
542 unsigned AS = PTy->getAddressSpace();
543
544 // If this is a float/double load, we can try folding it as an int32/64 load
545 // and then bitcast the result. This can be useful for union cases. Note
546 // that address spaces don't matter here since we're not going to result in
547 // an actual new load.
548 Type *MapTy;
549 if (LoadTy->isHalfTy())
550 MapTy = Type::getInt16Ty(C->getContext());
551 else if (LoadTy->isFloatTy())
552 MapTy = Type::getInt32Ty(C->getContext());
553 else if (LoadTy->isDoubleTy())
554 MapTy = Type::getInt64Ty(C->getContext());
555 else if (LoadTy->isVectorTy()) {
556 MapTy = PointerType::getIntNTy(
557 C->getContext(), DL.getTypeSizeInBits(LoadTy).getFixedSize());
558 } else
559 return nullptr;
560
561 C = FoldBitCast(C, MapTy->getPointerTo(AS), DL);
562 if (Constant *Res = FoldReinterpretLoadFromConstPtr(C, MapTy, DL)) {
563 if (Res->isNullValue() && !LoadTy->isX86_MMXTy())
564 // Materializing a zero can be done trivially without a bitcast
565 return Constant::getNullValue(LoadTy);
566 Type *CastTy = LoadTy->isPtrOrPtrVectorTy() ? DL.getIntPtrType(LoadTy) : LoadTy;
567 Res = FoldBitCast(Res, CastTy, DL);
568 if (LoadTy->isPtrOrPtrVectorTy()) {
569 // For vector of pointer, we needed to first convert to a vector of integer, then do vector inttoptr
570 if (Res->isNullValue() && !LoadTy->isX86_MMXTy())
571 return Constant::getNullValue(LoadTy);
572 if (DL.isNonIntegralPointerType(LoadTy->getScalarType()))
573 // Be careful not to replace a load of an addrspace value with an inttoptr here
574 return nullptr;
575 Res = ConstantExpr::getCast(Instruction::IntToPtr, Res, LoadTy);
576 }
577 return Res;
578 }
579 return nullptr;
580 }
581
582 unsigned BytesLoaded = (IntType->getBitWidth() + 7) / 8;
583 if (BytesLoaded > 32 || BytesLoaded == 0)
584 return nullptr;
585
586 GlobalValue *GVal;
587 APInt OffsetAI;
588 if (!IsConstantOffsetFromGlobal(C, GVal, OffsetAI, DL))
589 return nullptr;
590
591 auto *GV = dyn_cast<GlobalVariable>(GVal);
592 if (!GV || !GV->isConstant() || !GV->hasDefinitiveInitializer() ||
593 !GV->getInitializer()->getType()->isSized())
594 return nullptr;
595
596 int64_t Offset = OffsetAI.getSExtValue();
597 int64_t InitializerSize =
598 DL.getTypeAllocSize(GV->getInitializer()->getType()).getFixedSize();
599
600 // If we're not accessing anything in this constant, the result is undefined.
601 if (Offset <= -1 * static_cast<int64_t>(BytesLoaded))
602 return UndefValue::get(IntType);
603
604 // If we're not accessing anything in this constant, the result is undefined.
605 if (Offset >= InitializerSize)
606 return UndefValue::get(IntType);
607
608 unsigned char RawBytes[32] = {0};
609 unsigned char *CurPtr = RawBytes;
610 unsigned BytesLeft = BytesLoaded;
611
612 // If we're loading off the beginning of the global, some bytes may be valid.
613 if (Offset < 0) {
614 CurPtr += -Offset;
615 BytesLeft += Offset;
616 Offset = 0;
617 }
618
619 if (!ReadDataFromGlobal(GV->getInitializer(), Offset, CurPtr, BytesLeft, DL))
620 return nullptr;
621
622 APInt ResultVal = APInt(IntType->getBitWidth(), 0);
623 if (DL.isLittleEndian()) {
624 ResultVal = RawBytes[BytesLoaded - 1];
625 for (unsigned i = 1; i != BytesLoaded; ++i) {
626 ResultVal <<= 8;
627 ResultVal |= RawBytes[BytesLoaded - 1 - i];
628 }
629 } else {
630 ResultVal = RawBytes[0];
631 for (unsigned i = 1; i != BytesLoaded; ++i) {
632 ResultVal <<= 8;
633 ResultVal |= RawBytes[i];
634 }
635 }
636
637 return ConstantInt::get(IntType->getContext(), ResultVal);
638}
639
640Constant *ConstantFoldLoadThroughBitcastExpr(ConstantExpr *CE, Type *DestTy,
641 const DataLayout &DL) {
642 auto *SrcPtr = CE->getOperand(0);
643 auto *SrcPtrTy = dyn_cast<PointerType>(SrcPtr->getType());
644 if (!SrcPtrTy)
645 return nullptr;
646 Type *SrcTy = SrcPtrTy->getPointerElementType();
647
648 Constant *C = ConstantFoldLoadFromConstPtr(SrcPtr, SrcTy, DL);
649 if (!C)
650 return nullptr;
651
652 return llvm::ConstantFoldLoadThroughBitcast(C, DestTy, DL);
653}
654
655} // end anonymous namespace
656
657Constant *llvm::ConstantFoldLoadFromConstPtr(Constant *C, Type *Ty,
658 const DataLayout &DL) {
659 // First, try the easy cases:
660 if (auto *GV = dyn_cast<GlobalVariable>(C))
661 if (GV->isConstant() && GV->hasDefinitiveInitializer())
662 return GV->getInitializer();
663
664 if (auto *GA = dyn_cast<GlobalAlias>(C))
665 if (GA->getAliasee() && !GA->isInterposable())
666 return ConstantFoldLoadFromConstPtr(GA->getAliasee(), Ty, DL);
667
668 // If the loaded value isn't a constant expr, we can't handle it.
669 auto *CE = dyn_cast<ConstantExpr>(C);
670 if (!CE)
671 return nullptr;
672
673 if (CE->getOpcode() == Instruction::GetElementPtr) {
674 if (auto *GV = dyn_cast<GlobalVariable>(CE->getOperand(0))) {
675 if (GV->isConstant() && GV->hasDefinitiveInitializer()) {
676 if (Constant *V =
677 ConstantFoldLoadThroughGEPConstantExpr(GV->getInitializer(), CE))
678 return V;
679 }
680 }
681 }
682
683 if (CE->getOpcode() == Instruction::BitCast)
684 if (Constant *LoadedC = ConstantFoldLoadThroughBitcastExpr(CE, Ty, DL))
685 return LoadedC;
686
687 // Instead of loading constant c string, use corresponding integer value
688 // directly if string length is small enough.
689 StringRef Str;
690 if (getConstantStringInfo(CE, Str) && !Str.empty()) {
691 size_t StrLen = Str.size();
692 unsigned NumBits = Ty->getPrimitiveSizeInBits();
693 // Replace load with immediate integer if the result is an integer or fp
694 // value.
695 if ((NumBits >> 3) == StrLen + 1 && (NumBits & 7) == 0 &&
696 (isa<IntegerType>(Ty) || Ty->isFloatingPointTy())) {
697 APInt StrVal(NumBits, 0);
698 APInt SingleChar(NumBits, 0);
699 if (DL.isLittleEndian()) {
700 for (unsigned char C : reverse(Str.bytes())) {
701 SingleChar = static_cast<uint64_t>(C);
702 StrVal = (StrVal << 8) | SingleChar;
703 }
704 } else {
705 for (unsigned char C : Str.bytes()) {
706 SingleChar = static_cast<uint64_t>(C);
707 StrVal = (StrVal << 8) | SingleChar;
708 }
709 // Append NULL at the end.
710 SingleChar = 0;
711 StrVal = (StrVal << 8) | SingleChar;
712 }
713
714 Constant *Res = ConstantInt::get(CE->getContext(), StrVal);
715 if (Ty->isFloatingPointTy())
716 Res = ConstantExpr::getBitCast(Res, Ty);
717 return Res;
718 }
719 }
720
721 // If this load comes from anywhere in a constant global, and if the global
722 // is all undef or zero, we know what it loads.
723 if (auto *GV = dyn_cast<GlobalVariable>(getUnderlyingObject(CE))) {
724 if (GV->isConstant() && GV->hasDefinitiveInitializer()) {
725 if (GV->getInitializer()->isNullValue())
726 return Constant::getNullValue(Ty);
727 if (isa<UndefValue>(GV->getInitializer()))
728 return UndefValue::get(Ty);
729 }
730 }
731
732 // Try hard to fold loads from bitcasted strange and non-type-safe things.
733 return FoldReinterpretLoadFromConstPtr(CE, Ty, DL);
734}
735
736namespace {
737
738Constant *ConstantFoldLoadInst(const LoadInst *LI, const DataLayout &DL) {
739 if (LI->isVolatile()) return nullptr;
740
741 if (auto *C = dyn_cast<Constant>(LI->getOperand(0)))
742 return ConstantFoldLoadFromConstPtr(C, LI->getType(), DL);
743
744 return nullptr;
745}
746
747/// One of Op0/Op1 is a constant expression.
748/// Attempt to symbolically evaluate the result of a binary operator merging
749/// these together. If target data info is available, it is provided as DL,
750/// otherwise DL is null.
751Constant *SymbolicallyEvaluateBinop(unsigned Opc, Constant *Op0, Constant *Op1,
752 const DataLayout &DL) {
753 // SROA
754
755 // Fold (and 0xffffffff00000000, (shl x, 32)) -> shl.
756 // Fold (lshr (or X, Y), 32) -> (lshr [X/Y], 32) if one doesn't contribute
757 // bits.
758
759 if (Opc == Instruction::And) {
760 KnownBits Known0 = computeKnownBits(Op0, DL);
761 KnownBits Known1 = computeKnownBits(Op1, DL);
762 if ((Known1.One | Known0.Zero).isAllOnesValue()) {
763 // All the bits of Op0 that the 'and' could be masking are already zero.
764 return Op0;
765 }
766 if ((Known0.One | Known1.Zero).isAllOnesValue()) {
767 // All the bits of Op1 that the 'and' could be masking are already zero.
768 return Op1;
769 }
770
771 Known0 &= Known1;
772 if (Known0.isConstant())
773 return ConstantInt::get(Op0->getType(), Known0.getConstant());
774 }
775
776 // If the constant expr is something like &A[123] - &A[4].f, fold this into a
777 // constant. This happens frequently when iterating over a global array.
778 if (Opc == Instruction::Sub) {
779 GlobalValue *GV1, *GV2;
780 APInt Offs1, Offs2;
781
782 if (IsConstantOffsetFromGlobal(Op0, GV1, Offs1, DL))
783 if (IsConstantOffsetFromGlobal(Op1, GV2, Offs2, DL) && GV1 == GV2) {
784 unsigned OpSize = DL.getTypeSizeInBits(Op0->getType());
785
786 // (&GV+C1) - (&GV+C2) -> C1-C2, pointer arithmetic cannot overflow.
787 // PtrToInt may change the bitwidth so we have convert to the right size
788 // first.
789 return ConstantInt::get(Op0->getType(), Offs1.zextOrTrunc(OpSize) -
790 Offs2.zextOrTrunc(OpSize));
791 }
792 }
793
794 return nullptr;
795}
796
797/// If array indices are not pointer-sized integers, explicitly cast them so
798/// that they aren't implicitly casted by the getelementptr.
799Constant *CastGEPIndices(Type *SrcElemTy, ArrayRef<Constant *> Ops,
800 Type *ResultTy, Optional<unsigned> InRangeIndex,
801 const DataLayout &DL, const TargetLibraryInfo *TLI) {
802 Type *IntIdxTy = DL.getIndexType(ResultTy);
803 Type *IntIdxScalarTy = IntIdxTy->getScalarType();
804
805 bool Any = false;
806 SmallVector<Constant*, 32> NewIdxs;
807 for (unsigned i = 1, e = Ops.size(); i != e; ++i) {
808 if ((i == 1 ||
809 !isa<StructType>(GetElementPtrInst::getIndexedType(
810 SrcElemTy, Ops.slice(1, i - 1)))) &&
811 Ops[i]->getType()->getScalarType() != IntIdxScalarTy) {
812 Any = true;
813 Type *NewType = Ops[i]->getType()->isVectorTy()
814 ? IntIdxTy
815 : IntIdxScalarTy;
816 NewIdxs.push_back(ConstantExpr::getCast(CastInst::getCastOpcode(Ops[i],
817 true,
818 NewType,
819 true),
820 Ops[i], NewType));
821 } else
822 NewIdxs.push_back(Ops[i]);
823 }
824
825 if (!Any)
826 return nullptr;
827
828 Constant *C = ConstantExpr::getGetElementPtr(
829 SrcElemTy, Ops[0], NewIdxs, /*InBounds=*/false, InRangeIndex);
830 return ConstantFoldConstant(C, DL, TLI);
831}
832
833/// Strip the pointer casts, but preserve the address space information.
834Constant *StripPtrCastKeepAS(Constant *Ptr, Type *&ElemTy) {
835 assert(Ptr->getType()->isPointerTy() && "Not a pointer type")((Ptr->getType()->isPointerTy() && "Not a pointer type"
) ? static_cast<void> (0) : __assert_fail ("Ptr->getType()->isPointerTy() && \"Not a pointer type\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/lib/Analysis/ConstantFolding.cpp"
, 835, __PRETTY_FUNCTION__))
;
836 auto *OldPtrTy = cast<PointerType>(Ptr->getType());
837 Ptr = cast<Constant>(Ptr->stripPointerCasts());
838 auto *NewPtrTy = cast<PointerType>(Ptr->getType());
839
840 ElemTy = NewPtrTy->getPointerElementType();
841
842 // Preserve the address space number of the pointer.
843 if (NewPtrTy->getAddressSpace() != OldPtrTy->getAddressSpace()) {
844 NewPtrTy = ElemTy->getPointerTo(OldPtrTy->getAddressSpace());
845 Ptr = ConstantExpr::getPointerCast(Ptr, NewPtrTy);
846 }
847 return Ptr;
848}
849
850/// If we can symbolically evaluate the GEP constant expression, do so.
851Constant *SymbolicallyEvaluateGEP(const GEPOperator *GEP,
852 ArrayRef<Constant *> Ops,
853 const DataLayout &DL,
854 const TargetLibraryInfo *TLI) {
855 const GEPOperator *InnermostGEP = GEP;
856 bool InBounds = GEP->isInBounds();
857
858 Type *SrcElemTy = GEP->getSourceElementType();
859 Type *ResElemTy = GEP->getResultElementType();
860 Type *ResTy = GEP->getType();
861 if (!SrcElemTy->isSized() || isa<ScalableVectorType>(SrcElemTy))
862 return nullptr;
863
864 if (Constant *C = CastGEPIndices(SrcElemTy, Ops, ResTy,
865 GEP->getInRangeIndex(), DL, TLI))
866 return C;
867
868 Constant *Ptr = Ops[0];
869 if (!Ptr->getType()->isPointerTy())
870 return nullptr;
871
872 Type *IntIdxTy = DL.getIndexType(Ptr->getType());
873
874 // If this is a constant expr gep that is effectively computing an
875 // "offsetof", fold it into 'cast int Size to T*' instead of 'gep 0, 0, 12'
876 for (unsigned i = 1, e = Ops.size(); i != e; ++i)
877 if (!isa<ConstantInt>(Ops[i])) {
878
879 // If this is "gep i8* Ptr, (sub 0, V)", fold this as:
880 // "inttoptr (sub (ptrtoint Ptr), V)"
881 if (Ops.size() == 2 && ResElemTy->isIntegerTy(8)) {
882 auto *CE = dyn_cast<ConstantExpr>(Ops[1]);
883 assert((!CE || CE->getType() == IntIdxTy) &&(((!CE || CE->getType() == IntIdxTy) && "CastGEPIndices didn't canonicalize index types!"
) ? static_cast<void> (0) : __assert_fail ("(!CE || CE->getType() == IntIdxTy) && \"CastGEPIndices didn't canonicalize index types!\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/lib/Analysis/ConstantFolding.cpp"
, 884, __PRETTY_FUNCTION__))
884 "CastGEPIndices didn't canonicalize index types!")(((!CE || CE->getType() == IntIdxTy) && "CastGEPIndices didn't canonicalize index types!"
) ? static_cast<void> (0) : __assert_fail ("(!CE || CE->getType() == IntIdxTy) && \"CastGEPIndices didn't canonicalize index types!\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/lib/Analysis/ConstantFolding.cpp"
, 884, __PRETTY_FUNCTION__))
;
885 if (CE && CE->getOpcode() == Instruction::Sub &&
886 CE->getOperand(0)->isNullValue()) {
887 Constant *Res = ConstantExpr::getPtrToInt(Ptr, CE->getType());
888 Res = ConstantExpr::getSub(Res, CE->getOperand(1));
889 Res = ConstantExpr::getIntToPtr(Res, ResTy);
890 return ConstantFoldConstant(Res, DL, TLI);
891 }
892 }
893 return nullptr;
894 }
895
896 unsigned BitWidth = DL.getTypeSizeInBits(IntIdxTy);
897 APInt Offset =
898 APInt(BitWidth,
899 DL.getIndexedOffsetInType(
900 SrcElemTy,
901 makeArrayRef((Value * const *)Ops.data() + 1, Ops.size() - 1)));
902 Ptr = StripPtrCastKeepAS(Ptr, SrcElemTy);
903
904 // If this is a GEP of a GEP, fold it all into a single GEP.
905 while (auto *GEP = dyn_cast<GEPOperator>(Ptr)) {
906 InnermostGEP = GEP;
907 InBounds &= GEP->isInBounds();
908
909 SmallVector<Value *, 4> NestedOps(GEP->op_begin() + 1, GEP->op_end());
910
911 // Do not try the incorporate the sub-GEP if some index is not a number.
912 bool AllConstantInt = true;
913 for (Value *NestedOp : NestedOps)
914 if (!isa<ConstantInt>(NestedOp)) {
915 AllConstantInt = false;
916 break;
917 }
918 if (!AllConstantInt)
919 break;
920
921 Ptr = cast<Constant>(GEP->getOperand(0));
922 SrcElemTy = GEP->getSourceElementType();
923 Offset += APInt(BitWidth, DL.getIndexedOffsetInType(SrcElemTy, NestedOps));
924 Ptr = StripPtrCastKeepAS(Ptr, SrcElemTy);
925 }
926
927 // If the base value for this address is a literal integer value, fold the
928 // getelementptr to the resulting integer value casted to the pointer type.
929 APInt BasePtr(BitWidth, 0);
930 if (auto *CE = dyn_cast<ConstantExpr>(Ptr)) {
931 if (CE->getOpcode() == Instruction::IntToPtr) {
932 if (auto *Base = dyn_cast<ConstantInt>(CE->getOperand(0)))
933 BasePtr = Base->getValue().zextOrTrunc(BitWidth);
934 }
935 }
936
937 auto *PTy = cast<PointerType>(Ptr->getType());
938 if ((Ptr->isNullValue() || BasePtr != 0) &&
939 !DL.isNonIntegralPointerType(PTy)) {
940 Constant *C = ConstantInt::get(Ptr->getContext(), Offset + BasePtr);
941 return ConstantExpr::getIntToPtr(C, ResTy);
942 }
943
944 // Otherwise form a regular getelementptr. Recompute the indices so that
945 // we eliminate over-indexing of the notional static type array bounds.
946 // This makes it easy to determine if the getelementptr is "inbounds".
947 // Also, this helps GlobalOpt do SROA on GlobalVariables.
948 Type *Ty = PTy;
949 SmallVector<Constant *, 32> NewIdxs;
950
951 do {
952 if (!Ty->isStructTy()) {
953 if (Ty->isPointerTy()) {
954 // The only pointer indexing we'll do is on the first index of the GEP.
955 if (!NewIdxs.empty())
956 break;
957
958 Ty = SrcElemTy;
959
960 // Only handle pointers to sized types, not pointers to functions.
961 if (!Ty->isSized())
962 return nullptr;
963 } else {
964 Type *NextTy = GetElementPtrInst::getTypeAtIndex(Ty, (uint64_t)0);
965 if (!NextTy)
966 break;
967 Ty = NextTy;
968 }
969
970 // Determine which element of the array the offset points into.
971 APInt ElemSize(BitWidth, DL.getTypeAllocSize(Ty));
972 if (ElemSize == 0) {
973 // The element size is 0. This may be [0 x Ty]*, so just use a zero
974 // index for this level and proceed to the next level to see if it can
975 // accommodate the offset.
976 NewIdxs.push_back(ConstantInt::get(IntIdxTy, 0));
977 } else {
978 // The element size is non-zero divide the offset by the element
979 // size (rounding down), to compute the index at this level.
980 bool Overflow;
981 APInt NewIdx = Offset.sdiv_ov(ElemSize, Overflow);
982 if (Overflow)
983 break;
984 Offset -= NewIdx * ElemSize;
985 NewIdxs.push_back(ConstantInt::get(IntIdxTy, NewIdx));
986 }
987 } else {
988 auto *STy = cast<StructType>(Ty);
989 // If we end up with an offset that isn't valid for this struct type, we
990 // can't re-form this GEP in a regular form, so bail out. The pointer
991 // operand likely went through casts that are necessary to make the GEP
992 // sensible.
993 const StructLayout &SL = *DL.getStructLayout(STy);
994 if (Offset.isNegative() || Offset.uge(SL.getSizeInBytes()))
995 break;
996
997 // Determine which field of the struct the offset points into. The
998 // getZExtValue is fine as we've already ensured that the offset is
999 // within the range representable by the StructLayout API.
1000 unsigned ElIdx = SL.getElementContainingOffset(Offset.getZExtValue());
1001 NewIdxs.push_back(ConstantInt::get(Type::getInt32Ty(Ty->getContext()),
1002 ElIdx));
1003 Offset -= APInt(BitWidth, SL.getElementOffset(ElIdx));
1004 Ty = STy->getTypeAtIndex(ElIdx);
1005 }
1006 } while (Ty != ResElemTy);
1007
1008 // If we haven't used up the entire offset by descending the static
1009 // type, then the offset is pointing into the middle of an indivisible
1010 // member, so we can't simplify it.
1011 if (Offset != 0)
1012 return nullptr;
1013
1014 // Preserve the inrange index from the innermost GEP if possible. We must
1015 // have calculated the same indices up to and including the inrange index.
1016 Optional<unsigned> InRangeIndex;
1017 if (Optional<unsigned> LastIRIndex = InnermostGEP->getInRangeIndex())
1018 if (SrcElemTy == InnermostGEP->getSourceElementType() &&
1019 NewIdxs.size() > *LastIRIndex) {
1020 InRangeIndex = LastIRIndex;
1021 for (unsigned I = 0; I <= *LastIRIndex; ++I)
1022 if (NewIdxs[I] != InnermostGEP->getOperand(I + 1))
1023 return nullptr;
1024 }
1025
1026 // Create a GEP.
1027 Constant *C = ConstantExpr::getGetElementPtr(SrcElemTy, Ptr, NewIdxs,
1028 InBounds, InRangeIndex);
1029 assert(C->getType()->getPointerElementType() == Ty &&((C->getType()->getPointerElementType() == Ty &&
"Computed GetElementPtr has unexpected type!") ? static_cast
<void> (0) : __assert_fail ("C->getType()->getPointerElementType() == Ty && \"Computed GetElementPtr has unexpected type!\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/lib/Analysis/ConstantFolding.cpp"
, 1030, __PRETTY_FUNCTION__))
1030 "Computed GetElementPtr has unexpected type!")((C->getType()->getPointerElementType() == Ty &&
"Computed GetElementPtr has unexpected type!") ? static_cast
<void> (0) : __assert_fail ("C->getType()->getPointerElementType() == Ty && \"Computed GetElementPtr has unexpected type!\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/lib/Analysis/ConstantFolding.cpp"
, 1030, __PRETTY_FUNCTION__))
;
1031
1032 // If we ended up indexing a member with a type that doesn't match
1033 // the type of what the original indices indexed, add a cast.
1034 if (Ty != ResElemTy)
1035 C = FoldBitCast(C, ResTy, DL);
1036
1037 return C;
1038}
1039
1040/// Attempt to constant fold an instruction with the
1041/// specified opcode and operands. If successful, the constant result is
1042/// returned, if not, null is returned. Note that this function can fail when
1043/// attempting to fold instructions like loads and stores, which have no
1044/// constant expression form.
1045Constant *ConstantFoldInstOperandsImpl(const Value *InstOrCE, unsigned Opcode,
1046 ArrayRef<Constant *> Ops,
1047 const DataLayout &DL,
1048 const TargetLibraryInfo *TLI) {
1049 Type *DestTy = InstOrCE->getType();
1050
1051 if (Instruction::isUnaryOp(Opcode))
1052 return ConstantFoldUnaryOpOperand(Opcode, Ops[0], DL);
1053
1054 if (Instruction::isBinaryOp(Opcode))
1055 return ConstantFoldBinaryOpOperands(Opcode, Ops[0], Ops[1], DL);
1056
1057 if (Instruction::isCast(Opcode))
1058 return ConstantFoldCastOperand(Opcode, Ops[0], DestTy, DL);
1059
1060 if (auto *GEP = dyn_cast<GEPOperator>(InstOrCE)) {
1061 if (Constant *C = SymbolicallyEvaluateGEP(GEP, Ops, DL, TLI))
1062 return C;
1063
1064 return ConstantExpr::getGetElementPtr(GEP->getSourceElementType(), Ops[0],
1065 Ops.slice(1), GEP->isInBounds(),
1066 GEP->getInRangeIndex());
1067 }
1068
1069 if (auto *CE = dyn_cast<ConstantExpr>(InstOrCE))
1070 return CE->getWithOperands(Ops);
1071
1072 switch (Opcode) {
1073 default: return nullptr;
1074 case Instruction::ICmp:
1075 case Instruction::FCmp: llvm_unreachable("Invalid for compares")::llvm::llvm_unreachable_internal("Invalid for compares", "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/lib/Analysis/ConstantFolding.cpp"
, 1075)
;
1076 case Instruction::Freeze:
1077 return isGuaranteedNotToBeUndefOrPoison(Ops[0]) ? Ops[0] : nullptr;
1078 case Instruction::Call:
1079 if (auto *F = dyn_cast<Function>(Ops.back())) {
1080 const auto *Call = cast<CallBase>(InstOrCE);
1081 if (canConstantFoldCallTo(Call, F))
1082 return ConstantFoldCall(Call, F, Ops.slice(0, Ops.size() - 1), TLI);
1083 }
1084 return nullptr;
1085 case Instruction::Select:
1086 return ConstantExpr::getSelect(Ops[0], Ops[1], Ops[2]);
1087 case Instruction::ExtractElement:
1088 return ConstantExpr::getExtractElement(Ops[0], Ops[1]);
1089 case Instruction::ExtractValue:
1090 return ConstantExpr::getExtractValue(
1091 Ops[0], cast<ExtractValueInst>(InstOrCE)->getIndices());
1092 case Instruction::InsertElement:
1093 return ConstantExpr::getInsertElement(Ops[0], Ops[1], Ops[2]);
1094 case Instruction::ShuffleVector:
1095 return ConstantExpr::getShuffleVector(
1096 Ops[0], Ops[1], cast<ShuffleVectorInst>(InstOrCE)->getShuffleMask());
1097 }
1098}
1099
1100} // end anonymous namespace
1101
1102//===----------------------------------------------------------------------===//
1103// Constant Folding public APIs
1104//===----------------------------------------------------------------------===//
1105
1106namespace {
1107
1108Constant *
1109ConstantFoldConstantImpl(const Constant *C, const DataLayout &DL,
1110 const TargetLibraryInfo *TLI,
1111 SmallDenseMap<Constant *, Constant *> &FoldedOps) {
1112 if (!isa<ConstantVector>(C) && !isa<ConstantExpr>(C))
1113 return const_cast<Constant *>(C);
1114
1115 SmallVector<Constant *, 8> Ops;
1116 for (const Use &OldU : C->operands()) {
1117 Constant *OldC = cast<Constant>(&OldU);
1118 Constant *NewC = OldC;
1119 // Recursively fold the ConstantExpr's operands. If we have already folded
1120 // a ConstantExpr, we don't have to process it again.
1121 if (isa<ConstantVector>(OldC) || isa<ConstantExpr>(OldC)) {
1122 auto It = FoldedOps.find(OldC);
1123 if (It == FoldedOps.end()) {
1124 NewC = ConstantFoldConstantImpl(OldC, DL, TLI, FoldedOps);
1125 FoldedOps.insert({OldC, NewC});
1126 } else {
1127 NewC = It->second;
1128 }
1129 }
1130 Ops.push_back(NewC);
1131 }
1132
1133 if (auto *CE = dyn_cast<ConstantExpr>(C)) {
1134 if (CE->isCompare())
1135 return ConstantFoldCompareInstOperands(CE->getPredicate(), Ops[0], Ops[1],
1136 DL, TLI);
1137
1138 return ConstantFoldInstOperandsImpl(CE, CE->getOpcode(), Ops, DL, TLI);
1139 }
1140
1141 assert(isa<ConstantVector>(C))((isa<ConstantVector>(C)) ? static_cast<void> (0)
: __assert_fail ("isa<ConstantVector>(C)", "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/lib/Analysis/ConstantFolding.cpp"
, 1141, __PRETTY_FUNCTION__))
;
1142 return ConstantVector::get(Ops);
1143}
1144
1145} // end anonymous namespace
1146
1147Constant *llvm::ConstantFoldInstruction(Instruction *I, const DataLayout &DL,
1148 const TargetLibraryInfo *TLI) {
1149 // Handle PHI nodes quickly here...
1150 if (auto *PN = dyn_cast<PHINode>(I)) {
1151 Constant *CommonValue = nullptr;
1152
1153 SmallDenseMap<Constant *, Constant *> FoldedOps;
1154 for (Value *Incoming : PN->incoming_values()) {
1155 // If the incoming value is undef then skip it. Note that while we could
1156 // skip the value if it is equal to the phi node itself we choose not to
1157 // because that would break the rule that constant folding only applies if
1158 // all operands are constants.
1159 if (isa<UndefValue>(Incoming))
1160 continue;
1161 // If the incoming value is not a constant, then give up.
1162 auto *C = dyn_cast<Constant>(Incoming);
1163 if (!C)
1164 return nullptr;
1165 // Fold the PHI's operands.
1166 C = ConstantFoldConstantImpl(C, DL, TLI, FoldedOps);
1167 // If the incoming value is a different constant to
1168 // the one we saw previously, then give up.
1169 if (CommonValue && C != CommonValue)
1170 return nullptr;
1171 CommonValue = C;
1172 }
1173
1174 // If we reach here, all incoming values are the same constant or undef.
1175 return CommonValue ? CommonValue : UndefValue::get(PN->getType());
1176 }
1177
1178 // Scan the operand list, checking to see if they are all constants, if so,
1179 // hand off to ConstantFoldInstOperandsImpl.
1180 if (!all_of(I->operands(), [](Use &U) { return isa<Constant>(U); }))
1181 return nullptr;
1182
1183 SmallDenseMap<Constant *, Constant *> FoldedOps;
1184 SmallVector<Constant *, 8> Ops;
1185 for (const Use &OpU : I->operands()) {
1186 auto *Op = cast<Constant>(&OpU);
1187 // Fold the Instruction's operands.
1188 Op = ConstantFoldConstantImpl(Op, DL, TLI, FoldedOps);
1189 Ops.push_back(Op);
1190 }
1191
1192 if (const auto *CI = dyn_cast<CmpInst>(I))
1193 return ConstantFoldCompareInstOperands(CI->getPredicate(), Ops[0], Ops[1],
1194 DL, TLI);
1195
1196 if (const auto *LI = dyn_cast<LoadInst>(I))
1197 return ConstantFoldLoadInst(LI, DL);
1198
1199 if (auto *IVI = dyn_cast<InsertValueInst>(I)) {
1200 return ConstantExpr::getInsertValue(
1201 cast<Constant>(IVI->getAggregateOperand()),
1202 cast<Constant>(IVI->getInsertedValueOperand()),
1203 IVI->getIndices());
1204 }
1205
1206 if (auto *EVI = dyn_cast<ExtractValueInst>(I)) {
1207 return ConstantExpr::getExtractValue(
1208 cast<Constant>(EVI->getAggregateOperand()),
1209 EVI->getIndices());
1210 }
1211
1212 return ConstantFoldInstOperands(I, Ops, DL, TLI);
1213}
1214
1215Constant *llvm::ConstantFoldConstant(const Constant *C, const DataLayout &DL,
1216 const TargetLibraryInfo *TLI) {
1217 SmallDenseMap<Constant *, Constant *> FoldedOps;
1218 return ConstantFoldConstantImpl(C, DL, TLI, FoldedOps);
1219}
1220
1221Constant *llvm::ConstantFoldInstOperands(Instruction *I,
1222 ArrayRef<Constant *> Ops,
1223 const DataLayout &DL,
1224 const TargetLibraryInfo *TLI) {
1225 return ConstantFoldInstOperandsImpl(I, I->getOpcode(), Ops, DL, TLI);
1226}
1227
1228Constant *llvm::ConstantFoldCompareInstOperands(unsigned Predicate,
1229 Constant *Ops0, Constant *Ops1,
1230 const DataLayout &DL,
1231 const TargetLibraryInfo *TLI) {
1232 // fold: icmp (inttoptr x), null -> icmp x, 0
1233 // fold: icmp null, (inttoptr x) -> icmp 0, x
1234 // fold: icmp (ptrtoint x), 0 -> icmp x, null
1235 // fold: icmp 0, (ptrtoint x) -> icmp null, x
1236 // fold: icmp (inttoptr x), (inttoptr y) -> icmp trunc/zext x, trunc/zext y
1237 // fold: icmp (ptrtoint x), (ptrtoint y) -> icmp x, y
1238 //
1239 // FIXME: The following comment is out of data and the DataLayout is here now.
1240 // ConstantExpr::getCompare cannot do this, because it doesn't have DL
1241 // around to know if bit truncation is happening.
1242 if (auto *CE0 = dyn_cast<ConstantExpr>(Ops0)) {
1243 if (Ops1->isNullValue()) {
1244 if (CE0->getOpcode() == Instruction::IntToPtr) {
1245 Type *IntPtrTy = DL.getIntPtrType(CE0->getType());
1246 // Convert the integer value to the right size to ensure we get the
1247 // proper extension or truncation.
1248 Constant *C = ConstantExpr::getIntegerCast(CE0->getOperand(0),
1249 IntPtrTy, false);
1250 Constant *Null = Constant::getNullValue(C->getType());
1251 return ConstantFoldCompareInstOperands(Predicate, C, Null, DL, TLI);
1252 }
1253
1254 // Only do this transformation if the int is intptrty in size, otherwise
1255 // there is a truncation or extension that we aren't modeling.
1256 if (CE0->getOpcode() == Instruction::PtrToInt) {
1257 Type *IntPtrTy = DL.getIntPtrType(CE0->getOperand(0)->getType());
1258 if (CE0->getType() == IntPtrTy) {
1259 Constant *C = CE0->getOperand(0);
1260 Constant *Null = Constant::getNullValue(C->getType());
1261 return ConstantFoldCompareInstOperands(Predicate, C, Null, DL, TLI);
1262 }
1263 }
1264 }
1265
1266 if (auto *CE1 = dyn_cast<ConstantExpr>(Ops1)) {
1267 if (CE0->getOpcode() == CE1->getOpcode()) {
1268 if (CE0->getOpcode() == Instruction::IntToPtr) {
1269 Type *IntPtrTy = DL.getIntPtrType(CE0->getType());
1270
1271 // Convert the integer value to the right size to ensure we get the
1272 // proper extension or truncation.
1273 Constant *C0 = ConstantExpr::getIntegerCast(CE0->getOperand(0),
1274 IntPtrTy, false);
1275 Constant *C1 = ConstantExpr::getIntegerCast(CE1->getOperand(0),
1276 IntPtrTy, false);
1277 return ConstantFoldCompareInstOperands(Predicate, C0, C1, DL, TLI);
1278 }
1279
1280 // Only do this transformation if the int is intptrty in size, otherwise
1281 // there is a truncation or extension that we aren't modeling.
1282 if (CE0->getOpcode() == Instruction::PtrToInt) {
1283 Type *IntPtrTy = DL.getIntPtrType(CE0->getOperand(0)->getType());
1284 if (CE0->getType() == IntPtrTy &&
1285 CE0->getOperand(0)->getType() == CE1->getOperand(0)->getType()) {
1286 return ConstantFoldCompareInstOperands(
1287 Predicate, CE0->getOperand(0), CE1->getOperand(0), DL, TLI);
1288 }
1289 }
1290 }
1291 }
1292
1293 // icmp eq (or x, y), 0 -> (icmp eq x, 0) & (icmp eq y, 0)
1294 // icmp ne (or x, y), 0 -> (icmp ne x, 0) | (icmp ne y, 0)
1295 if ((Predicate == ICmpInst::ICMP_EQ || Predicate == ICmpInst::ICMP_NE) &&
1296 CE0->getOpcode() == Instruction::Or && Ops1->isNullValue()) {
1297 Constant *LHS = ConstantFoldCompareInstOperands(
1298 Predicate, CE0->getOperand(0), Ops1, DL, TLI);
1299 Constant *RHS = ConstantFoldCompareInstOperands(
1300 Predicate, CE0->getOperand(1), Ops1, DL, TLI);
1301 unsigned OpC =
1302 Predicate == ICmpInst::ICMP_EQ ? Instruction::And : Instruction::Or;
1303 return ConstantFoldBinaryOpOperands(OpC, LHS, RHS, DL);
1304 }
1305 } else if (isa<ConstantExpr>(Ops1)) {
1306 // If RHS is a constant expression, but the left side isn't, swap the
1307 // operands and try again.
1308 Predicate = ICmpInst::getSwappedPredicate((ICmpInst::Predicate)Predicate);
1309 return ConstantFoldCompareInstOperands(Predicate, Ops1, Ops0, DL, TLI);
1310 }
1311
1312 return ConstantExpr::getCompare(Predicate, Ops0, Ops1);
1313}
1314
1315Constant *llvm::ConstantFoldUnaryOpOperand(unsigned Opcode, Constant *Op,
1316 const DataLayout &DL) {
1317 assert(Instruction::isUnaryOp(Opcode))((Instruction::isUnaryOp(Opcode)) ? static_cast<void> (
0) : __assert_fail ("Instruction::isUnaryOp(Opcode)", "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/lib/Analysis/ConstantFolding.cpp"
, 1317, __PRETTY_FUNCTION__))
;
1318
1319 return ConstantExpr::get(Opcode, Op);
1320}
1321
1322Constant *llvm::ConstantFoldBinaryOpOperands(unsigned Opcode, Constant *LHS,
1323 Constant *RHS,
1324 const DataLayout &DL) {
1325 assert(Instruction::isBinaryOp(Opcode))((Instruction::isBinaryOp(Opcode)) ? static_cast<void> (
0) : __assert_fail ("Instruction::isBinaryOp(Opcode)", "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/lib/Analysis/ConstantFolding.cpp"
, 1325, __PRETTY_FUNCTION__))
;
1326 if (isa<ConstantExpr>(LHS) || isa<ConstantExpr>(RHS))
1327 if (Constant *C = SymbolicallyEvaluateBinop(Opcode, LHS, RHS, DL))
1328 return C;
1329
1330 return ConstantExpr::get(Opcode, LHS, RHS);
1331}
1332
1333Constant *llvm::ConstantFoldCastOperand(unsigned Opcode, Constant *C,
1334 Type *DestTy, const DataLayout &DL) {
1335 assert(Instruction::isCast(Opcode))((Instruction::isCast(Opcode)) ? static_cast<void> (0) :
__assert_fail ("Instruction::isCast(Opcode)", "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/lib/Analysis/ConstantFolding.cpp"
, 1335, __PRETTY_FUNCTION__))
;
1336 switch (Opcode) {
1337 default:
1338 llvm_unreachable("Missing case")::llvm::llvm_unreachable_internal("Missing case", "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/lib/Analysis/ConstantFolding.cpp"
, 1338)
;
1339 case Instruction::PtrToInt:
1340 // If the input is a inttoptr, eliminate the pair. This requires knowing
1341 // the width of a pointer, so it can't be done in ConstantExpr::getCast.
1342 if (auto *CE = dyn_cast<ConstantExpr>(C)) {
1343 if (CE->getOpcode() == Instruction::IntToPtr) {
1344 Constant *Input = CE->getOperand(0);
1345 unsigned InWidth = Input->getType()->getScalarSizeInBits();
1346 unsigned PtrWidth = DL.getPointerTypeSizeInBits(CE->getType());
1347 if (PtrWidth < InWidth) {
1348 Constant *Mask =
1349 ConstantInt::get(CE->getContext(),
1350 APInt::getLowBitsSet(InWidth, PtrWidth));
1351 Input = ConstantExpr::getAnd(Input, Mask);
1352 }
1353 // Do a zext or trunc to get to the dest size.
1354 return ConstantExpr::getIntegerCast(Input, DestTy, false);
1355 }
1356 }
1357 return ConstantExpr::getCast(Opcode, C, DestTy);
1358 case Instruction::IntToPtr:
1359 // If the input is a ptrtoint, turn the pair into a ptr to ptr bitcast if
1360 // the int size is >= the ptr size and the address spaces are the same.
1361 // This requires knowing the width of a pointer, so it can't be done in
1362 // ConstantExpr::getCast.
1363 if (auto *CE = dyn_cast<ConstantExpr>(C)) {
1364 if (CE->getOpcode() == Instruction::PtrToInt) {
1365 Constant *SrcPtr = CE->getOperand(0);
1366 unsigned SrcPtrSize = DL.getPointerTypeSizeInBits(SrcPtr->getType());
1367 unsigned MidIntSize = CE->getType()->getScalarSizeInBits();
1368
1369 if (MidIntSize >= SrcPtrSize) {
1370 unsigned SrcAS = SrcPtr->getType()->getPointerAddressSpace();
1371 if (SrcAS == DestTy->getPointerAddressSpace())
1372 return FoldBitCast(CE->getOperand(0), DestTy, DL);
1373 }
1374 }
1375 }
1376
1377 return ConstantExpr::getCast(Opcode, C, DestTy);
1378 case Instruction::Trunc:
1379 case Instruction::ZExt:
1380 case Instruction::SExt:
1381 case Instruction::FPTrunc:
1382 case Instruction::FPExt:
1383 case Instruction::UIToFP:
1384 case Instruction::SIToFP:
1385 case Instruction::FPToUI:
1386 case Instruction::FPToSI:
1387 case Instruction::AddrSpaceCast:
1388 return ConstantExpr::getCast(Opcode, C, DestTy);
1389 case Instruction::BitCast:
1390 return FoldBitCast(C, DestTy, DL);
1391 }
1392}
1393
1394Constant *llvm::ConstantFoldLoadThroughGEPConstantExpr(Constant *C,
1395 ConstantExpr *CE) {
1396 if (!CE->getOperand(1)->isNullValue())
1397 return nullptr; // Do not allow stepping over the value!
1398
1399 // Loop over all of the operands, tracking down which value we are
1400 // addressing.
1401 for (unsigned i = 2, e = CE->getNumOperands(); i != e; ++i) {
1402 C = C->getAggregateElement(CE->getOperand(i));
1403 if (!C)
1404 return nullptr;
1405 }
1406 return C;
1407}
1408
1409Constant *
1410llvm::ConstantFoldLoadThroughGEPIndices(Constant *C,
1411 ArrayRef<Constant *> Indices) {
1412 // Loop over all of the operands, tracking down which value we are
1413 // addressing.
1414 for (Constant *Index : Indices) {
1415 C = C->getAggregateElement(Index);
1416 if (!C)
1417 return nullptr;
1418 }
1419 return C;
1420}
1421
1422//===----------------------------------------------------------------------===//
1423// Constant Folding for Calls
1424//
1425
1426bool llvm::canConstantFoldCallTo(const CallBase *Call, const Function *F) {
1427 if (Call->isNoBuiltin())
1428 return false;
1429 switch (F->getIntrinsicID()) {
1430 // Operations that do not operate floating-point numbers and do not depend on
1431 // FP environment can be folded even in strictfp functions.
1432 case Intrinsic::bswap:
1433 case Intrinsic::ctpop:
1434 case Intrinsic::ctlz:
1435 case Intrinsic::cttz:
1436 case Intrinsic::fshl:
1437 case Intrinsic::fshr:
1438 case Intrinsic::launder_invariant_group:
1439 case Intrinsic::strip_invariant_group:
1440 case Intrinsic::masked_load:
1441 case Intrinsic::abs:
1442 case Intrinsic::smax:
1443 case Intrinsic::smin:
1444 case Intrinsic::umax:
1445 case Intrinsic::umin:
1446 case Intrinsic::sadd_with_overflow:
1447 case Intrinsic::uadd_with_overflow:
1448 case Intrinsic::ssub_with_overflow:
1449 case Intrinsic::usub_with_overflow:
1450 case Intrinsic::smul_with_overflow:
1451 case Intrinsic::umul_with_overflow:
1452 case Intrinsic::sadd_sat:
1453 case Intrinsic::uadd_sat:
1454 case Intrinsic::ssub_sat:
1455 case Intrinsic::usub_sat:
1456 case Intrinsic::smul_fix:
1457 case Intrinsic::smul_fix_sat:
1458 case Intrinsic::bitreverse:
1459 case Intrinsic::is_constant:
1460 case Intrinsic::experimental_vector_reduce_add:
1461 case Intrinsic::experimental_vector_reduce_mul:
1462 case Intrinsic::experimental_vector_reduce_and:
1463 case Intrinsic::experimental_vector_reduce_or:
1464 case Intrinsic::experimental_vector_reduce_xor:
1465 case Intrinsic::experimental_vector_reduce_smin:
1466 case Intrinsic::experimental_vector_reduce_smax:
1467 case Intrinsic::experimental_vector_reduce_umin:
1468 case Intrinsic::experimental_vector_reduce_umax:
1469 // Target intrinsics
1470 case Intrinsic::arm_mve_vctp8:
1471 case Intrinsic::arm_mve_vctp16:
1472 case Intrinsic::arm_mve_vctp32:
1473 case Intrinsic::arm_mve_vctp64:
1474 // WebAssembly float semantics are always known
1475 case Intrinsic::wasm_trunc_signed:
1476 case Intrinsic::wasm_trunc_unsigned:
1477 case Intrinsic::wasm_trunc_saturate_signed:
1478 case Intrinsic::wasm_trunc_saturate_unsigned:
1479 return true;
1480
1481 // Floating point operations cannot be folded in strictfp functions in
1482 // general case. They can be folded if FP environment is known to compiler.
1483 case Intrinsic::minnum:
1484 case Intrinsic::maxnum:
1485 case Intrinsic::minimum:
1486 case Intrinsic::maximum:
1487 case Intrinsic::log:
1488 case Intrinsic::log2:
1489 case Intrinsic::log10:
1490 case Intrinsic::exp:
1491 case Intrinsic::exp2:
1492 case Intrinsic::sqrt:
1493 case Intrinsic::sin:
1494 case Intrinsic::cos:
1495 case Intrinsic::pow:
1496 case Intrinsic::powi:
1497 case Intrinsic::fma:
1498 case Intrinsic::fmuladd:
1499 case Intrinsic::convert_from_fp16:
1500 case Intrinsic::convert_to_fp16:
1501 case Intrinsic::amdgcn_cos:
1502 case Intrinsic::amdgcn_cubeid:
1503 case Intrinsic::amdgcn_cubema:
1504 case Intrinsic::amdgcn_cubesc:
1505 case Intrinsic::amdgcn_cubetc:
1506 case Intrinsic::amdgcn_fmul_legacy:
1507 case Intrinsic::amdgcn_fract:
1508 case Intrinsic::amdgcn_ldexp:
1509 case Intrinsic::amdgcn_sin:
1510 // The intrinsics below depend on rounding mode in MXCSR.
1511 case Intrinsic::x86_sse_cvtss2si:
1512 case Intrinsic::x86_sse_cvtss2si64:
1513 case Intrinsic::x86_sse_cvttss2si:
1514 case Intrinsic::x86_sse_cvttss2si64:
1515 case Intrinsic::x86_sse2_cvtsd2si:
1516 case Intrinsic::x86_sse2_cvtsd2si64:
1517 case Intrinsic::x86_sse2_cvttsd2si:
1518 case Intrinsic::x86_sse2_cvttsd2si64:
1519 case Intrinsic::x86_avx512_vcvtss2si32:
1520 case Intrinsic::x86_avx512_vcvtss2si64:
1521 case Intrinsic::x86_avx512_cvttss2si:
1522 case Intrinsic::x86_avx512_cvttss2si64:
1523 case Intrinsic::x86_avx512_vcvtsd2si32:
1524 case Intrinsic::x86_avx512_vcvtsd2si64:
1525 case Intrinsic::x86_avx512_cvttsd2si:
1526 case Intrinsic::x86_avx512_cvttsd2si64:
1527 case Intrinsic::x86_avx512_vcvtss2usi32:
1528 case Intrinsic::x86_avx512_vcvtss2usi64:
1529 case Intrinsic::x86_avx512_cvttss2usi:
1530 case Intrinsic::x86_avx512_cvttss2usi64:
1531 case Intrinsic::x86_avx512_vcvtsd2usi32:
1532 case Intrinsic::x86_avx512_vcvtsd2usi64:
1533 case Intrinsic::x86_avx512_cvttsd2usi:
1534 case Intrinsic::x86_avx512_cvttsd2usi64:
1535 return !Call->isStrictFP();
1536
1537 // Sign operations are actually bitwise operations, they do not raise
1538 // exceptions even for SNANs.
1539 case Intrinsic::fabs:
1540 case Intrinsic::copysign:
1541 // Non-constrained variants of rounding operations means default FP
1542 // environment, they can be folded in any case.
1543 case Intrinsic::ceil:
1544 case Intrinsic::floor:
1545 case Intrinsic::round:
1546 case Intrinsic::roundeven:
1547 case Intrinsic::trunc:
1548 case Intrinsic::nearbyint:
1549 case Intrinsic::rint:
1550 // Constrained intrinsics can be folded if FP environment is known
1551 // to compiler.
1552 case Intrinsic::experimental_constrained_ceil:
1553 case Intrinsic::experimental_constrained_floor:
1554 case Intrinsic::experimental_constrained_round:
1555 case Intrinsic::experimental_constrained_roundeven:
1556 case Intrinsic::experimental_constrained_trunc:
1557 case Intrinsic::experimental_constrained_nearbyint:
1558 case Intrinsic::experimental_constrained_rint:
1559 return true;
1560 default:
1561 return false;
1562 case Intrinsic::not_intrinsic: break;
1563 }
1564
1565 if (!F->hasName() || Call->isStrictFP())
1566 return false;
1567
1568 // In these cases, the check of the length is required. We don't want to
1569 // return true for a name like "cos\0blah" which strcmp would return equal to
1570 // "cos", but has length 8.
1571 StringRef Name = F->getName();
1572 switch (Name[0]) {
1573 default:
1574 return false;
1575 case 'a':
1576 return Name == "acos" || Name == "acosf" ||
1577 Name == "asin" || Name == "asinf" ||
1578 Name == "atan" || Name == "atanf" ||
1579 Name == "atan2" || Name == "atan2f";
1580 case 'c':
1581 return Name == "ceil" || Name == "ceilf" ||
1582 Name == "cos" || Name == "cosf" ||
1583 Name == "cosh" || Name == "coshf";
1584 case 'e':
1585 return Name == "exp" || Name == "expf" ||
1586 Name == "exp2" || Name == "exp2f";
1587 case 'f':
1588 return Name == "fabs" || Name == "fabsf" ||
1589 Name == "floor" || Name == "floorf" ||
1590 Name == "fmod" || Name == "fmodf";
1591 case 'l':
1592 return Name == "log" || Name == "logf" ||
1593 Name == "log2" || Name == "log2f" ||
1594 Name == "log10" || Name == "log10f";
1595 case 'n':
1596 return Name == "nearbyint" || Name == "nearbyintf";
1597 case 'p':
1598 return Name == "pow" || Name == "powf";
1599 case 'r':
1600 return Name == "remainder" || Name == "remainderf" ||
1601 Name == "rint" || Name == "rintf" ||
1602 Name == "round" || Name == "roundf";
1603 case 's':
1604 return Name == "sin" || Name == "sinf" ||
1605 Name == "sinh" || Name == "sinhf" ||
1606 Name == "sqrt" || Name == "sqrtf";
1607 case 't':
1608 return Name == "tan" || Name == "tanf" ||
1609 Name == "tanh" || Name == "tanhf" ||
1610 Name == "trunc" || Name == "truncf";
1611 case '_':
1612 // Check for various function names that get used for the math functions
1613 // when the header files are preprocessed with the macro
1614 // __FINITE_MATH_ONLY__ enabled.
1615 // The '12' here is the length of the shortest name that can match.
1616 // We need to check the size before looking at Name[1] and Name[2]
1617 // so we may as well check a limit that will eliminate mismatches.
1618 if (Name.size() < 12 || Name[1] != '_')
1619 return false;
1620 switch (Name[2]) {
1621 default:
1622 return false;
1623 case 'a':
1624 return Name == "__acos_finite" || Name == "__acosf_finite" ||
1625 Name == "__asin_finite" || Name == "__asinf_finite" ||
1626 Name == "__atan2_finite" || Name == "__atan2f_finite";
1627 case 'c':
1628 return Name == "__cosh_finite" || Name == "__coshf_finite";
1629 case 'e':
1630 return Name == "__exp_finite" || Name == "__expf_finite" ||
1631 Name == "__exp2_finite" || Name == "__exp2f_finite";
1632 case 'l':
1633 return Name == "__log_finite" || Name == "__logf_finite" ||
1634 Name == "__log10_finite" || Name == "__log10f_finite";
1635 case 'p':
1636 return Name == "__pow_finite" || Name == "__powf_finite";
1637 case 's':
1638 return Name == "__sinh_finite" || Name == "__sinhf_finite";
1639 }
1640 }
1641}
1642
1643namespace {
1644
1645Constant *GetConstantFoldFPValue(double V, Type *Ty) {
1646 if (Ty->isHalfTy() || Ty->isFloatTy()) {
1647 APFloat APF(V);
1648 bool unused;
1649 APF.convert(Ty->getFltSemantics(), APFloat::rmNearestTiesToEven, &unused);
1650 return ConstantFP::get(Ty->getContext(), APF);
1651 }
1652 if (Ty->isDoubleTy())
1653 return ConstantFP::get(Ty->getContext(), APFloat(V));
1654 llvm_unreachable("Can only constant fold half/float/double")::llvm::llvm_unreachable_internal("Can only constant fold half/float/double"
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/lib/Analysis/ConstantFolding.cpp"
, 1654)
;
1655}
1656
1657/// Clear the floating-point exception state.
1658inline void llvm_fenv_clearexcept() {
1659#if defined(HAVE_FENV_H1) && HAVE_DECL_FE_ALL_EXCEPT1
1660 feclearexcept(FE_ALL_EXCEPT(0x20 | 0x04 | 0x10 | 0x08 | 0x01));
1661#endif
1662 errno(*__errno_location ()) = 0;
1663}
1664
1665/// Test if a floating-point exception was raised.
1666inline bool llvm_fenv_testexcept() {
1667 int errno_val = errno(*__errno_location ());
1668 if (errno_val == ERANGE34 || errno_val == EDOM33)
1669 return true;
1670#if defined(HAVE_FENV_H1) && HAVE_DECL_FE_ALL_EXCEPT1 && HAVE_DECL_FE_INEXACT1
1671 if (fetestexcept(FE_ALL_EXCEPT(0x20 | 0x04 | 0x10 | 0x08 | 0x01) & ~FE_INEXACT0x20))
1672 return true;
1673#endif
1674 return false;
1675}
1676
1677Constant *ConstantFoldFP(double (*NativeFP)(double), double V, Type *Ty) {
1678 llvm_fenv_clearexcept();
1679 V = NativeFP(V);
1680 if (llvm_fenv_testexcept()) {
1681 llvm_fenv_clearexcept();
1682 return nullptr;
1683 }
1684
1685 return GetConstantFoldFPValue(V, Ty);
1686}
1687
1688Constant *ConstantFoldBinaryFP(double (*NativeFP)(double, double), double V,
1689 double W, Type *Ty) {
1690 llvm_fenv_clearexcept();
1691 V = NativeFP(V, W);
1692 if (llvm_fenv_testexcept()) {
1693 llvm_fenv_clearexcept();
1694 return nullptr;
1695 }
1696
1697 return GetConstantFoldFPValue(V, Ty);
1698}
1699
1700Constant *ConstantFoldVectorReduce(Intrinsic::ID IID, Constant *Op) {
1701 FixedVectorType *VT = dyn_cast<FixedVectorType>(Op->getType());
1702 if (!VT)
1703 return nullptr;
1704 ConstantInt *CI = dyn_cast<ConstantInt>(Op->getAggregateElement(0U));
1705 if (!CI)
1706 return nullptr;
1707 APInt Acc = CI->getValue();
1708
1709 for (unsigned I = 1; I < VT->getNumElements(); I++) {
1710 if (!(CI = dyn_cast<ConstantInt>(Op->getAggregateElement(I))))
1711 return nullptr;
1712 const APInt &X = CI->getValue();
1713 switch (IID) {
1714 case Intrinsic::experimental_vector_reduce_add:
1715 Acc = Acc + X;
1716 break;
1717 case Intrinsic::experimental_vector_reduce_mul:
1718 Acc = Acc * X;
1719 break;
1720 case Intrinsic::experimental_vector_reduce_and:
1721 Acc = Acc & X;
1722 break;
1723 case Intrinsic::experimental_vector_reduce_or:
1724 Acc = Acc | X;
1725 break;
1726 case Intrinsic::experimental_vector_reduce_xor:
1727 Acc = Acc ^ X;
1728 break;
1729 case Intrinsic::experimental_vector_reduce_smin:
1730 Acc = APIntOps::smin(Acc, X);
1731 break;
1732 case Intrinsic::experimental_vector_reduce_smax:
1733 Acc = APIntOps::smax(Acc, X);
1734 break;
1735 case Intrinsic::experimental_vector_reduce_umin:
1736 Acc = APIntOps::umin(Acc, X);
1737 break;
1738 case Intrinsic::experimental_vector_reduce_umax:
1739 Acc = APIntOps::umax(Acc, X);
1740 break;
1741 }
1742 }
1743
1744 return ConstantInt::get(Op->getContext(), Acc);
1745}
1746
1747/// Attempt to fold an SSE floating point to integer conversion of a constant
1748/// floating point. If roundTowardZero is false, the default IEEE rounding is
1749/// used (toward nearest, ties to even). This matches the behavior of the
1750/// non-truncating SSE instructions in the default rounding mode. The desired
1751/// integer type Ty is used to select how many bits are available for the
1752/// result. Returns null if the conversion cannot be performed, otherwise
1753/// returns the Constant value resulting from the conversion.
1754Constant *ConstantFoldSSEConvertToInt(const APFloat &Val, bool roundTowardZero,
1755 Type *Ty, bool IsSigned) {
1756 // All of these conversion intrinsics form an integer of at most 64bits.
1757 unsigned ResultWidth = Ty->getIntegerBitWidth();
1758 assert(ResultWidth <= 64 &&((ResultWidth <= 64 && "Can only constant fold conversions to 64 and 32 bit ints"
) ? static_cast<void> (0) : __assert_fail ("ResultWidth <= 64 && \"Can only constant fold conversions to 64 and 32 bit ints\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/lib/Analysis/ConstantFolding.cpp"
, 1759, __PRETTY_FUNCTION__))
1759 "Can only constant fold conversions to 64 and 32 bit ints")((ResultWidth <= 64 && "Can only constant fold conversions to 64 and 32 bit ints"
) ? static_cast<void> (0) : __assert_fail ("ResultWidth <= 64 && \"Can only constant fold conversions to 64 and 32 bit ints\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/lib/Analysis/ConstantFolding.cpp"
, 1759, __PRETTY_FUNCTION__))
;
1760
1761 uint64_t UIntVal;
1762 bool isExact = false;
1763 APFloat::roundingMode mode = roundTowardZero? APFloat::rmTowardZero
1764 : APFloat::rmNearestTiesToEven;
1765 APFloat::opStatus status =
1766 Val.convertToInteger(makeMutableArrayRef(UIntVal), ResultWidth,
1767 IsSigned, mode, &isExact);
1768 if (status != APFloat::opOK &&
1769 (!roundTowardZero || status != APFloat::opInexact))
1770 return nullptr;
1771 return ConstantInt::get(Ty, UIntVal, IsSigned);
1772}
1773
1774double getValueAsDouble(ConstantFP *Op) {
1775 Type *Ty = Op->getType();
1776
1777 if (Ty->isFloatTy())
1778 return Op->getValueAPF().convertToFloat();
1779
1780 if (Ty->isDoubleTy())
1781 return Op->getValueAPF().convertToDouble();
1782
1783 bool unused;
1784 APFloat APF = Op->getValueAPF();
1785 APF.convert(APFloat::IEEEdouble(), APFloat::rmNearestTiesToEven, &unused);
1786 return APF.convertToDouble();
1787}
1788
1789static bool isManifestConstant(const Constant *c) {
1790 if (isa<ConstantData>(c)) {
1791 return true;
1792 } else if (isa<ConstantAggregate>(c) || isa<ConstantExpr>(c)) {
1793 for (const Value *subc : c->operand_values()) {
1794 if (!isManifestConstant(cast<Constant>(subc)))
1795 return false;
1796 }
1797 return true;
1798 }
1799 return false;
1800}
1801
1802static bool getConstIntOrUndef(Value *Op, const APInt *&C) {
1803 if (auto *CI
15.1
'CI' is null
23.1
'CI' is non-null
15.1
'CI' is null
23.1
'CI' is non-null
15.1
'CI' is null
23.1
'CI' is non-null
= dyn_cast<ConstantInt>(Op)) {
15
Assuming 'Op' is not a 'ConstantInt'
16
Taking false branch
23
Assuming 'Op' is a 'ConstantInt'
24
Taking true branch
1804 C = &CI->getValue();
1805 return true;
25
Returning the value 1, which participates in a condition later
1806 }
1807 if (isa<UndefValue>(Op)) {
17
Assuming 'Op' is a 'UndefValue'
18
Taking true branch
1808 C = nullptr;
19
Null pointer value stored to 'C0'
1809 return true;
20
Returning the value 1, which participates in a condition later
1810 }
1811 return false;
1812}
1813
1814static Constant *ConstantFoldScalarCall1(StringRef Name,
1815 Intrinsic::ID IntrinsicID,
1816 Type *Ty,
1817 ArrayRef<Constant *> Operands,
1818 const TargetLibraryInfo *TLI,
1819 const CallBase *Call) {
1820 assert(Operands.size() == 1 && "Wrong number of operands.")((Operands.size() == 1 && "Wrong number of operands."
) ? static_cast<void> (0) : __assert_fail ("Operands.size() == 1 && \"Wrong number of operands.\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/lib/Analysis/ConstantFolding.cpp"
, 1820, __PRETTY_FUNCTION__))
;
1821
1822 if (IntrinsicID == Intrinsic::is_constant) {
1823 // We know we have a "Constant" argument. But we want to only
1824 // return true for manifest constants, not those that depend on
1825 // constants with unknowable values, e.g. GlobalValue or BlockAddress.
1826 if (isManifestConstant(Operands[0]))
1827 return ConstantInt::getTrue(Ty->getContext());
1828 return nullptr;
1829 }
1830 if (isa<UndefValue>(Operands[0])) {
1831 // cosine(arg) is between -1 and 1. cosine(invalid arg) is NaN.
1832 // ctpop() is between 0 and bitwidth, pick 0 for undef.
1833 if (IntrinsicID == Intrinsic::cos ||
1834 IntrinsicID == Intrinsic::ctpop)
1835 return Constant::getNullValue(Ty);
1836 if (IntrinsicID == Intrinsic::bswap ||
1837 IntrinsicID == Intrinsic::bitreverse ||
1838 IntrinsicID == Intrinsic::launder_invariant_group ||
1839 IntrinsicID == Intrinsic::strip_invariant_group)
1840 return Operands[0];
1841 }
1842
1843 if (isa<ConstantPointerNull>(Operands[0])) {
1844 // launder(null) == null == strip(null) iff in addrspace 0
1845 if (IntrinsicID == Intrinsic::launder_invariant_group ||
1846 IntrinsicID == Intrinsic::strip_invariant_group) {
1847 // If instruction is not yet put in a basic block (e.g. when cloning
1848 // a function during inlining), Call's caller may not be available.
1849 // So check Call's BB first before querying Call->getCaller.
1850 const Function *Caller =
1851 Call->getParent() ? Call->getCaller() : nullptr;
1852 if (Caller &&
1853 !NullPointerIsDefined(
1854 Caller, Operands[0]->getType()->getPointerAddressSpace())) {
1855 return Operands[0];
1856 }
1857 return nullptr;
1858 }
1859 }
1860
1861 if (auto *Op = dyn_cast<ConstantFP>(Operands[0])) {
1862 if (IntrinsicID == Intrinsic::convert_to_fp16) {
1863 APFloat Val(Op->getValueAPF());
1864
1865 bool lost = false;
1866 Val.convert(APFloat::IEEEhalf(), APFloat::rmNearestTiesToEven, &lost);
1867
1868 return ConstantInt::get(Ty->getContext(), Val.bitcastToAPInt());
1869 }
1870
1871 APFloat U = Op->getValueAPF();
1872
1873 if (IntrinsicID == Intrinsic::wasm_trunc_signed ||
1874 IntrinsicID == Intrinsic::wasm_trunc_unsigned ||
1875 IntrinsicID == Intrinsic::wasm_trunc_saturate_signed ||
1876 IntrinsicID == Intrinsic::wasm_trunc_saturate_unsigned) {
1877
1878 bool Saturating = IntrinsicID == Intrinsic::wasm_trunc_saturate_signed ||
1879 IntrinsicID == Intrinsic::wasm_trunc_saturate_unsigned;
1880 bool Signed = IntrinsicID == Intrinsic::wasm_trunc_signed ||
1881 IntrinsicID == Intrinsic::wasm_trunc_saturate_signed;
1882
1883 if (U.isNaN())
1884 return Saturating ? ConstantInt::get(Ty, 0) : nullptr;
1885
1886 unsigned Width = Ty->getIntegerBitWidth();
1887 APSInt Int(Width, !Signed);
1888 bool IsExact = false;
1889 APFloat::opStatus Status =
1890 U.convertToInteger(Int, APFloat::rmTowardZero, &IsExact);
1891
1892 if (Status == APFloat::opOK || Status == APFloat::opInexact)
1893 return ConstantInt::get(Ty, Int);
1894
1895 if (!Saturating)
1896 return nullptr;
1897
1898 if (U.isNegative())
1899 return Signed ? ConstantInt::get(Ty, APInt::getSignedMinValue(Width))
1900 : ConstantInt::get(Ty, APInt::getMinValue(Width));
1901 else
1902 return Signed ? ConstantInt::get(Ty, APInt::getSignedMaxValue(Width))
1903 : ConstantInt::get(Ty, APInt::getMaxValue(Width));
1904 }
1905
1906 if (!Ty->isHalfTy() && !Ty->isFloatTy() && !Ty->isDoubleTy())
1907 return nullptr;
1908
1909 // Use internal versions of these intrinsics.
1910
1911 if (IntrinsicID == Intrinsic::nearbyint || IntrinsicID == Intrinsic::rint) {
1912 U.roundToIntegral(APFloat::rmNearestTiesToEven);
1913 return ConstantFP::get(Ty->getContext(), U);
1914 }
1915
1916 if (IntrinsicID == Intrinsic::round) {
1917 U.roundToIntegral(APFloat::rmNearestTiesToAway);
1918 return ConstantFP::get(Ty->getContext(), U);
1919 }
1920
1921 if (IntrinsicID == Intrinsic::roundeven) {
1922 U.roundToIntegral(APFloat::rmNearestTiesToEven);
1923 return ConstantFP::get(Ty->getContext(), U);
1924 }
1925
1926 if (IntrinsicID == Intrinsic::ceil) {
1927 U.roundToIntegral(APFloat::rmTowardPositive);
1928 return ConstantFP::get(Ty->getContext(), U);
1929 }
1930
1931 if (IntrinsicID == Intrinsic::floor) {
1932 U.roundToIntegral(APFloat::rmTowardNegative);
1933 return ConstantFP::get(Ty->getContext(), U);
1934 }
1935
1936 if (IntrinsicID == Intrinsic::trunc) {
1937 U.roundToIntegral(APFloat::rmTowardZero);
1938 return ConstantFP::get(Ty->getContext(), U);
1939 }
1940
1941 if (IntrinsicID == Intrinsic::fabs) {
1942 U.clearSign();
1943 return ConstantFP::get(Ty->getContext(), U);
1944 }
1945
1946 if (IntrinsicID == Intrinsic::amdgcn_fract) {
1947 // The v_fract instruction behaves like the OpenCL spec, which defines
1948 // fract(x) as fmin(x - floor(x), 0x1.fffffep-1f): "The min() operator is
1949 // there to prevent fract(-small) from returning 1.0. It returns the
1950 // largest positive floating-point number less than 1.0."
1951 APFloat FloorU(U);
1952 FloorU.roundToIntegral(APFloat::rmTowardNegative);
1953 APFloat FractU(U - FloorU);
1954 APFloat AlmostOne(U.getSemantics(), 1);
1955 AlmostOne.next(/*nextDown*/ true);
1956 return ConstantFP::get(Ty->getContext(), minimum(FractU, AlmostOne));
1957 }
1958
1959 // Rounding operations (floor, trunc, ceil, round and nearbyint) do not
1960 // raise FP exceptions, unless the argument is signaling NaN.
1961
1962 Optional<APFloat::roundingMode> RM;
1963 switch (IntrinsicID) {
1964 default:
1965 break;
1966 case Intrinsic::experimental_constrained_nearbyint:
1967 case Intrinsic::experimental_constrained_rint: {
1968 auto CI = cast<ConstrainedFPIntrinsic>(Call);
1969 RM = CI->getRoundingMode();
1970 if (!RM || RM.getValue() == RoundingMode::Dynamic)
1971 return nullptr;
1972 break;
1973 }
1974 case Intrinsic::experimental_constrained_round:
1975 RM = APFloat::rmNearestTiesToAway;
1976 break;
1977 case Intrinsic::experimental_constrained_ceil:
1978 RM = APFloat::rmTowardPositive;
1979 break;
1980 case Intrinsic::experimental_constrained_floor:
1981 RM = APFloat::rmTowardNegative;
1982 break;
1983 case Intrinsic::experimental_constrained_trunc:
1984 RM = APFloat::rmTowardZero;
1985 break;
1986 }
1987 if (RM) {
1988 auto CI = cast<ConstrainedFPIntrinsic>(Call);
1989 if (U.isFinite()) {
1990 APFloat::opStatus St = U.roundToIntegral(*RM);
1991 if (IntrinsicID == Intrinsic::experimental_constrained_rint &&
1992 St == APFloat::opInexact) {
1993 Optional<fp::ExceptionBehavior> EB = CI->getExceptionBehavior();
1994 if (EB && *EB == fp::ebStrict)
1995 return nullptr;
1996 }
1997 } else if (U.isSignaling()) {
1998 Optional<fp::ExceptionBehavior> EB = CI->getExceptionBehavior();
1999 if (EB && *EB != fp::ebIgnore)
2000 return nullptr;
2001 U = APFloat::getQNaN(U.getSemantics());
2002 }
2003 return ConstantFP::get(Ty->getContext(), U);
2004 }
2005
2006 /// We only fold functions with finite arguments. Folding NaN and inf is
2007 /// likely to be aborted with an exception anyway, and some host libms
2008 /// have known errors raising exceptions.
2009 if (!U.isFinite())
2010 return nullptr;
2011
2012 /// Currently APFloat versions of these functions do not exist, so we use
2013 /// the host native double versions. Float versions are not called
2014 /// directly but for all these it is true (float)(f((double)arg)) ==
2015 /// f(arg). Long double not supported yet.
2016 double V = getValueAsDouble(Op);
2017
2018 switch (IntrinsicID) {
2019 default: break;
2020 case Intrinsic::log:
2021 return ConstantFoldFP(log, V, Ty);
2022 case Intrinsic::log2:
2023 // TODO: What about hosts that lack a C99 library?
2024 return ConstantFoldFP(Log2, V, Ty);
2025 case Intrinsic::log10:
2026 // TODO: What about hosts that lack a C99 library?
2027 return ConstantFoldFP(log10, V, Ty);
2028 case Intrinsic::exp:
2029 return ConstantFoldFP(exp, V, Ty);
2030 case Intrinsic::exp2:
2031 // Fold exp2(x) as pow(2, x), in case the host lacks a C99 library.
2032 return ConstantFoldBinaryFP(pow, 2.0, V, Ty);
2033 case Intrinsic::sin:
2034 return ConstantFoldFP(sin, V, Ty);
2035 case Intrinsic::cos:
2036 return ConstantFoldFP(cos, V, Ty);
2037 case Intrinsic::sqrt:
2038 return ConstantFoldFP(sqrt, V, Ty);
2039 case Intrinsic::amdgcn_cos:
2040 case Intrinsic::amdgcn_sin:
2041 if (V < -256.0 || V > 256.0)
2042 // The gfx8 and gfx9 architectures handle arguments outside the range
2043 // [-256, 256] differently. This should be a rare case so bail out
2044 // rather than trying to handle the difference.
2045 return nullptr;
2046 bool IsCos = IntrinsicID == Intrinsic::amdgcn_cos;
2047 double V4 = V * 4.0;
2048 if (V4 == floor(V4)) {
2049 // Force exact results for quarter-integer inputs.
2050 const double SinVals[4] = { 0.0, 1.0, 0.0, -1.0 };
2051 V = SinVals[((int)V4 + (IsCos ? 1 : 0)) & 3];
2052 } else {
2053 if (IsCos)
2054 V = cos(V * 2.0 * numbers::pi);
2055 else
2056 V = sin(V * 2.0 * numbers::pi);
2057 }
2058 return GetConstantFoldFPValue(V, Ty);
2059 }
2060
2061 if (!TLI)
2062 return nullptr;
2063
2064 LibFunc Func = NotLibFunc;
2065 TLI->getLibFunc(Name, Func);
2066 switch (Func) {
2067 default:
2068 break;
2069 case LibFunc_acos:
2070 case LibFunc_acosf:
2071 case LibFunc_acos_finite:
2072 case LibFunc_acosf_finite:
2073 if (TLI->has(Func))
2074 return ConstantFoldFP(acos, V, Ty);
2075 break;
2076 case LibFunc_asin:
2077 case LibFunc_asinf:
2078 case LibFunc_asin_finite:
2079 case LibFunc_asinf_finite:
2080 if (TLI->has(Func))
2081 return ConstantFoldFP(asin, V, Ty);
2082 break;
2083 case LibFunc_atan:
2084 case LibFunc_atanf:
2085 if (TLI->has(Func))
2086 return ConstantFoldFP(atan, V, Ty);
2087 break;
2088 case LibFunc_ceil:
2089 case LibFunc_ceilf:
2090 if (TLI->has(Func)) {
2091 U.roundToIntegral(APFloat::rmTowardPositive);
2092 return ConstantFP::get(Ty->getContext(), U);
2093 }
2094 break;
2095 case LibFunc_cos:
2096 case LibFunc_cosf:
2097 if (TLI->has(Func))
2098 return ConstantFoldFP(cos, V, Ty);
2099 break;
2100 case LibFunc_cosh:
2101 case LibFunc_coshf:
2102 case LibFunc_cosh_finite:
2103 case LibFunc_coshf_finite:
2104 if (TLI->has(Func))
2105 return ConstantFoldFP(cosh, V, Ty);
2106 break;
2107 case LibFunc_exp:
2108 case LibFunc_expf:
2109 case LibFunc_exp_finite:
2110 case LibFunc_expf_finite:
2111 if (TLI->has(Func))
2112 return ConstantFoldFP(exp, V, Ty);
2113 break;
2114 case LibFunc_exp2:
2115 case LibFunc_exp2f:
2116 case LibFunc_exp2_finite:
2117 case LibFunc_exp2f_finite:
2118 if (TLI->has(Func))
2119 // Fold exp2(x) as pow(2, x), in case the host lacks a C99 library.
2120 return ConstantFoldBinaryFP(pow, 2.0, V, Ty);
2121 break;
2122 case LibFunc_fabs:
2123 case LibFunc_fabsf:
2124 if (TLI->has(Func)) {
2125 U.clearSign();
2126 return ConstantFP::get(Ty->getContext(), U);
2127 }
2128 break;
2129 case LibFunc_floor:
2130 case LibFunc_floorf:
2131 if (TLI->has(Func)) {
2132 U.roundToIntegral(APFloat::rmTowardNegative);
2133 return ConstantFP::get(Ty->getContext(), U);
2134 }
2135 break;
2136 case LibFunc_log:
2137 case LibFunc_logf:
2138 case LibFunc_log_finite:
2139 case LibFunc_logf_finite:
2140 if (V > 0.0 && TLI->has(Func))
2141 return ConstantFoldFP(log, V, Ty);
2142 break;
2143 case LibFunc_log2:
2144 case LibFunc_log2f:
2145 case LibFunc_log2_finite:
2146 case LibFunc_log2f_finite:
2147 if (V > 0.0 && TLI->has(Func))
2148 // TODO: What about hosts that lack a C99 library?
2149 return ConstantFoldFP(Log2, V, Ty);
2150 break;
2151 case LibFunc_log10:
2152 case LibFunc_log10f:
2153 case LibFunc_log10_finite:
2154 case LibFunc_log10f_finite:
2155 if (V > 0.0 && TLI->has(Func))
2156 // TODO: What about hosts that lack a C99 library?
2157 return ConstantFoldFP(log10, V, Ty);
2158 break;
2159 case LibFunc_nearbyint:
2160 case LibFunc_nearbyintf:
2161 case LibFunc_rint:
2162 case LibFunc_rintf:
2163 if (TLI->has(Func)) {
2164 U.roundToIntegral(APFloat::rmNearestTiesToEven);
2165 return ConstantFP::get(Ty->getContext(), U);
2166 }
2167 break;
2168 case LibFunc_round:
2169 case LibFunc_roundf:
2170 if (TLI->has(Func)) {
2171 U.roundToIntegral(APFloat::rmNearestTiesToAway);
2172 return ConstantFP::get(Ty->getContext(), U);
2173 }
2174 break;
2175 case LibFunc_sin:
2176 case LibFunc_sinf:
2177 if (TLI->has(Func))
2178 return ConstantFoldFP(sin, V, Ty);
2179 break;
2180 case LibFunc_sinh:
2181 case LibFunc_sinhf:
2182 case LibFunc_sinh_finite:
2183 case LibFunc_sinhf_finite:
2184 if (TLI->has(Func))
2185 return ConstantFoldFP(sinh, V, Ty);
2186 break;
2187 case LibFunc_sqrt:
2188 case LibFunc_sqrtf:
2189 if (V >= 0.0 && TLI->has(Func))
2190 return ConstantFoldFP(sqrt, V, Ty);
2191 break;
2192 case LibFunc_tan:
2193 case LibFunc_tanf:
2194 if (TLI->has(Func))
2195 return ConstantFoldFP(tan, V, Ty);
2196 break;
2197 case LibFunc_tanh:
2198 case LibFunc_tanhf:
2199 if (TLI->has(Func))
2200 return ConstantFoldFP(tanh, V, Ty);
2201 break;
2202 case LibFunc_trunc:
2203 case LibFunc_truncf:
2204 if (TLI->has(Func)) {
2205 U.roundToIntegral(APFloat::rmTowardZero);
2206 return ConstantFP::get(Ty->getContext(), U);
2207 }
2208 break;
2209 }
2210 return nullptr;
2211 }
2212
2213 if (auto *Op = dyn_cast<ConstantInt>(Operands[0])) {
2214 switch (IntrinsicID) {
2215 case Intrinsic::bswap:
2216 return ConstantInt::get(Ty->getContext(), Op->getValue().byteSwap());
2217 case Intrinsic::ctpop:
2218 return ConstantInt::get(Ty, Op->getValue().countPopulation());
2219 case Intrinsic::bitreverse:
2220 return ConstantInt::get(Ty->getContext(), Op->getValue().reverseBits());
2221 case Intrinsic::convert_from_fp16: {
2222 APFloat Val(APFloat::IEEEhalf(), Op->getValue());
2223
2224 bool lost = false;
2225 APFloat::opStatus status = Val.convert(
2226 Ty->getFltSemantics(), APFloat::rmNearestTiesToEven, &lost);
2227
2228 // Conversion is always precise.
2229 (void)status;
2230 assert(status == APFloat::opOK && !lost &&((status == APFloat::opOK && !lost && "Precision lost during fp16 constfolding"
) ? static_cast<void> (0) : __assert_fail ("status == APFloat::opOK && !lost && \"Precision lost during fp16 constfolding\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/lib/Analysis/ConstantFolding.cpp"
, 2231, __PRETTY_FUNCTION__))
2231 "Precision lost during fp16 constfolding")((status == APFloat::opOK && !lost && "Precision lost during fp16 constfolding"
) ? static_cast<void> (0) : __assert_fail ("status == APFloat::opOK && !lost && \"Precision lost during fp16 constfolding\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/lib/Analysis/ConstantFolding.cpp"
, 2231, __PRETTY_FUNCTION__))
;
2232
2233 return ConstantFP::get(Ty->getContext(), Val);
2234 }
2235 default:
2236 return nullptr;
2237 }
2238 }
2239
2240 if (isa<ConstantAggregateZero>(Operands[0])) {
2241 switch (IntrinsicID) {
2242 default: break;
2243 case Intrinsic::experimental_vector_reduce_add:
2244 case Intrinsic::experimental_vector_reduce_mul:
2245 case Intrinsic::experimental_vector_reduce_and:
2246 case Intrinsic::experimental_vector_reduce_or:
2247 case Intrinsic::experimental_vector_reduce_xor:
2248 case Intrinsic::experimental_vector_reduce_smin:
2249 case Intrinsic::experimental_vector_reduce_smax:
2250 case Intrinsic::experimental_vector_reduce_umin:
2251 case Intrinsic::experimental_vector_reduce_umax:
2252 return ConstantInt::get(Ty, 0);
2253 }
2254 }
2255
2256 // Support ConstantVector in case we have an Undef in the top.
2257 if (isa<ConstantVector>(Operands[0]) ||
2258 isa<ConstantDataVector>(Operands[0])) {
2259 auto *Op = cast<Constant>(Operands[0]);
2260 switch (IntrinsicID) {
2261 default: break;
2262 case Intrinsic::experimental_vector_reduce_add:
2263 case Intrinsic::experimental_vector_reduce_mul:
2264 case Intrinsic::experimental_vector_reduce_and:
2265 case Intrinsic::experimental_vector_reduce_or:
2266 case Intrinsic::experimental_vector_reduce_xor:
2267 case Intrinsic::experimental_vector_reduce_smin:
2268 case Intrinsic::experimental_vector_reduce_smax:
2269 case Intrinsic::experimental_vector_reduce_umin:
2270 case Intrinsic::experimental_vector_reduce_umax:
2271 if (Constant *C = ConstantFoldVectorReduce(IntrinsicID, Op))
2272 return C;
2273 break;
2274 case Intrinsic::x86_sse_cvtss2si:
2275 case Intrinsic::x86_sse_cvtss2si64:
2276 case Intrinsic::x86_sse2_cvtsd2si:
2277 case Intrinsic::x86_sse2_cvtsd2si64:
2278 if (ConstantFP *FPOp =
2279 dyn_cast_or_null<ConstantFP>(Op->getAggregateElement(0U)))
2280 return ConstantFoldSSEConvertToInt(FPOp->getValueAPF(),
2281 /*roundTowardZero=*/false, Ty,
2282 /*IsSigned*/true);
2283 break;
2284 case Intrinsic::x86_sse_cvttss2si:
2285 case Intrinsic::x86_sse_cvttss2si64:
2286 case Intrinsic::x86_sse2_cvttsd2si:
2287 case Intrinsic::x86_sse2_cvttsd2si64:
2288 if (ConstantFP *FPOp =
2289 dyn_cast_or_null<ConstantFP>(Op->getAggregateElement(0U)))
2290 return ConstantFoldSSEConvertToInt(FPOp->getValueAPF(),
2291 /*roundTowardZero=*/true, Ty,
2292 /*IsSigned*/true);
2293 break;
2294 }
2295 }
2296
2297 return nullptr;
2298}
2299
2300static Constant *ConstantFoldScalarCall2(StringRef Name,
2301 Intrinsic::ID IntrinsicID,
2302 Type *Ty,
2303 ArrayRef<Constant *> Operands,
2304 const TargetLibraryInfo *TLI,
2305 const CallBase *Call) {
2306 assert(Operands.size() == 2 && "Wrong number of operands.")((Operands.size() == 2 && "Wrong number of operands."
) ? static_cast<void> (0) : __assert_fail ("Operands.size() == 2 && \"Wrong number of operands.\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/lib/Analysis/ConstantFolding.cpp"
, 2306, __PRETTY_FUNCTION__))
;
1
Assuming the condition is true
2
'?' condition is true
2307
2308 if (auto *Op1
3.1
'Op1' is null
3.1
'Op1' is null
3.1
'Op1' is null
= dyn_cast<ConstantFP>(Operands[0])) {
3
Assuming the object is not a 'ConstantFP'
4
Taking false branch
2309 if (!Ty->isHalfTy() && !Ty->isFloatTy() && !Ty->isDoubleTy())
2310 return nullptr;
2311 double Op1V = getValueAsDouble(Op1);
2312
2313 if (auto *Op2 = dyn_cast<ConstantFP>(Operands[1])) {
2314 if (Op2->getType() != Op1->getType())
2315 return nullptr;
2316
2317 double Op2V = getValueAsDouble(Op2);
2318 if (IntrinsicID == Intrinsic::pow) {
2319 return ConstantFoldBinaryFP(pow, Op1V, Op2V, Ty);
2320 }
2321 if (IntrinsicID == Intrinsic::copysign) {
2322 APFloat V1 = Op1->getValueAPF();
2323 const APFloat &V2 = Op2->getValueAPF();
2324 V1.copySign(V2);
2325 return ConstantFP::get(Ty->getContext(), V1);
2326 }
2327
2328 if (IntrinsicID == Intrinsic::minnum) {
2329 const APFloat &C1 = Op1->getValueAPF();
2330 const APFloat &C2 = Op2->getValueAPF();
2331 return ConstantFP::get(Ty->getContext(), minnum(C1, C2));
2332 }
2333
2334 if (IntrinsicID == Intrinsic::maxnum) {
2335 const APFloat &C1 = Op1->getValueAPF();
2336 const APFloat &C2 = Op2->getValueAPF();
2337 return ConstantFP::get(Ty->getContext(), maxnum(C1, C2));
2338 }
2339
2340 if (IntrinsicID == Intrinsic::minimum) {
2341 const APFloat &C1 = Op1->getValueAPF();
2342 const APFloat &C2 = Op2->getValueAPF();
2343 return ConstantFP::get(Ty->getContext(), minimum(C1, C2));
2344 }
2345
2346 if (IntrinsicID == Intrinsic::maximum) {
2347 const APFloat &C1 = Op1->getValueAPF();
2348 const APFloat &C2 = Op2->getValueAPF();
2349 return ConstantFP::get(Ty->getContext(), maximum(C1, C2));
2350 }
2351
2352 if (IntrinsicID == Intrinsic::amdgcn_fmul_legacy) {
2353 const APFloat &C1 = Op1->getValueAPF();
2354 const APFloat &C2 = Op2->getValueAPF();
2355 // The legacy behaviour is that multiplying zero by anything, even NaN
2356 // or infinity, gives +0.0.
2357 if (C1.isZero() || C2.isZero())
2358 return ConstantFP::getNullValue(Ty);
2359 return ConstantFP::get(Ty->getContext(), C1 * C2);
2360 }
2361
2362 if (!TLI)
2363 return nullptr;
2364
2365 LibFunc Func = NotLibFunc;
2366 TLI->getLibFunc(Name, Func);
2367 switch (Func) {
2368 default:
2369 break;
2370 case LibFunc_pow:
2371 case LibFunc_powf:
2372 case LibFunc_pow_finite:
2373 case LibFunc_powf_finite:
2374 if (TLI->has(Func))
2375 return ConstantFoldBinaryFP(pow, Op1V, Op2V, Ty);
2376 break;
2377 case LibFunc_fmod:
2378 case LibFunc_fmodf:
2379 if (TLI->has(Func)) {
2380 APFloat V = Op1->getValueAPF();
2381 if (APFloat::opStatus::opOK == V.mod(Op2->getValueAPF()))
2382 return ConstantFP::get(Ty->getContext(), V);
2383 }
2384 break;
2385 case LibFunc_remainder:
2386 case LibFunc_remainderf:
2387 if (TLI->has(Func)) {
2388 APFloat V = Op1->getValueAPF();
2389 if (APFloat::opStatus::opOK == V.remainder(Op2->getValueAPF()))
2390 return ConstantFP::get(Ty->getContext(), V);
2391 }
2392 break;
2393 case LibFunc_atan2:
2394 case LibFunc_atan2f:
2395 case LibFunc_atan2_finite:
2396 case LibFunc_atan2f_finite:
2397 if (TLI->has(Func))
2398 return ConstantFoldBinaryFP(atan2, Op1V, Op2V, Ty);
2399 break;
2400 }
2401 } else if (auto *Op2C = dyn_cast<ConstantInt>(Operands[1])) {
2402 if (IntrinsicID == Intrinsic::powi && Ty->isHalfTy())
2403 return ConstantFP::get(Ty->getContext(),
2404 APFloat((float)std::pow((float)Op1V,
2405 (int)Op2C->getZExtValue())));
2406 if (IntrinsicID == Intrinsic::powi && Ty->isFloatTy())
2407 return ConstantFP::get(Ty->getContext(),
2408 APFloat((float)std::pow((float)Op1V,
2409 (int)Op2C->getZExtValue())));
2410 if (IntrinsicID == Intrinsic::powi && Ty->isDoubleTy())
2411 return ConstantFP::get(Ty->getContext(),
2412 APFloat((double)std::pow((double)Op1V,
2413 (int)Op2C->getZExtValue())));
2414
2415 if (IntrinsicID == Intrinsic::amdgcn_ldexp) {
2416 // FIXME: Should flush denorms depending on FP mode, but that's ignored
2417 // everywhere else.
2418
2419 // scalbn is equivalent to ldexp with float radix 2
2420 APFloat Result = scalbn(Op1->getValueAPF(), Op2C->getSExtValue(),
2421 APFloat::rmNearestTiesToEven);
2422 return ConstantFP::get(Ty->getContext(), Result);
2423 }
2424 }
2425 return nullptr;
2426 }
2427
2428 if (Operands[0]->getType()->isIntegerTy() &&
5
Calling 'Type::isIntegerTy'
8
Returning from 'Type::isIntegerTy'
13
Taking true branch
2429 Operands[1]->getType()->isIntegerTy()) {
9
Calling 'Type::isIntegerTy'
12
Returning from 'Type::isIntegerTy'
2430 const APInt *C0, *C1;
2431 if (!getConstIntOrUndef(Operands[0], C0) ||
14
Calling 'getConstIntOrUndef'
21
Returning from 'getConstIntOrUndef'
27
Taking false branch
2432 !getConstIntOrUndef(Operands[1], C1))
22
Calling 'getConstIntOrUndef'
26
Returning from 'getConstIntOrUndef'
2433 return nullptr;
2434
2435 unsigned BitWidth = Ty->getScalarSizeInBits();
2436 switch (IntrinsicID) {
28
Control jumps to 'case abs:' at line 2551
2437 default: break;
2438 case Intrinsic::smax:
2439 if (!C0 && !C1)
2440 return UndefValue::get(Ty);
2441 if (!C0 || !C1)
2442 return ConstantInt::get(Ty, APInt::getSignedMaxValue(BitWidth));
2443 return ConstantInt::get(Ty, C0->sgt(*C1) ? *C0 : *C1);
2444
2445 case Intrinsic::smin:
2446 if (!C0 && !C1)
2447 return UndefValue::get(Ty);
2448 if (!C0 || !C1)
2449 return ConstantInt::get(Ty, APInt::getSignedMinValue(BitWidth));
2450 return ConstantInt::get(Ty, C0->slt(*C1) ? *C0 : *C1);
2451
2452 case Intrinsic::umax:
2453 if (!C0 && !C1)
2454 return UndefValue::get(Ty);
2455 if (!C0 || !C1)
2456 return ConstantInt::get(Ty, APInt::getMaxValue(BitWidth));
2457 return ConstantInt::get(Ty, C0->ugt(*C1) ? *C0 : *C1);
2458
2459 case Intrinsic::umin:
2460 if (!C0 && !C1)
2461 return UndefValue::get(Ty);
2462 if (!C0 || !C1)
2463 return ConstantInt::get(Ty, APInt::getMinValue(BitWidth));
2464 return ConstantInt::get(Ty, C0->ult(*C1) ? *C0 : *C1);
2465
2466 case Intrinsic::usub_with_overflow:
2467 case Intrinsic::ssub_with_overflow:
2468 case Intrinsic::uadd_with_overflow:
2469 case Intrinsic::sadd_with_overflow:
2470 // X - undef -> { undef, false }
2471 // undef - X -> { undef, false }
2472 // X + undef -> { undef, false }
2473 // undef + x -> { undef, false }
2474 if (!C0 || !C1) {
2475 return ConstantStruct::get(
2476 cast<StructType>(Ty),
2477 {UndefValue::get(Ty->getStructElementType(0)),
2478 Constant::getNullValue(Ty->getStructElementType(1))});
2479 }
2480 LLVM_FALLTHROUGH[[gnu::fallthrough]];
2481 case Intrinsic::smul_with_overflow:
2482 case Intrinsic::umul_with_overflow: {
2483 // undef * X -> { 0, false }
2484 // X * undef -> { 0, false }
2485 if (!C0 || !C1)
2486 return Constant::getNullValue(Ty);
2487
2488 APInt Res;
2489 bool Overflow;
2490 switch (IntrinsicID) {
2491 default: llvm_unreachable("Invalid case")::llvm::llvm_unreachable_internal("Invalid case", "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/lib/Analysis/ConstantFolding.cpp"
, 2491)
;
2492 case Intrinsic::sadd_with_overflow:
2493 Res = C0->sadd_ov(*C1, Overflow);
2494 break;
2495 case Intrinsic::uadd_with_overflow:
2496 Res = C0->uadd_ov(*C1, Overflow);
2497 break;
2498 case Intrinsic::ssub_with_overflow:
2499 Res = C0->ssub_ov(*C1, Overflow);
2500 break;
2501 case Intrinsic::usub_with_overflow:
2502 Res = C0->usub_ov(*C1, Overflow);
2503 break;
2504 case Intrinsic::smul_with_overflow:
2505 Res = C0->smul_ov(*C1, Overflow);
2506 break;
2507 case Intrinsic::umul_with_overflow:
2508 Res = C0->umul_ov(*C1, Overflow);
2509 break;
2510 }
2511 Constant *Ops[] = {
2512 ConstantInt::get(Ty->getContext(), Res),
2513 ConstantInt::get(Type::getInt1Ty(Ty->getContext()), Overflow)
2514 };
2515 return ConstantStruct::get(cast<StructType>(Ty), Ops);
2516 }
2517 case Intrinsic::uadd_sat:
2518 case Intrinsic::sadd_sat:
2519 if (!C0 && !C1)
2520 return UndefValue::get(Ty);
2521 if (!C0 || !C1)
2522 return Constant::getAllOnesValue(Ty);
2523 if (IntrinsicID == Intrinsic::uadd_sat)
2524 return ConstantInt::get(Ty, C0->uadd_sat(*C1));
2525 else
2526 return ConstantInt::get(Ty, C0->sadd_sat(*C1));
2527 case Intrinsic::usub_sat:
2528 case Intrinsic::ssub_sat:
2529 if (!C0 && !C1)
2530 return UndefValue::get(Ty);
2531 if (!C0 || !C1)
2532 return Constant::getNullValue(Ty);
2533 if (IntrinsicID == Intrinsic::usub_sat)
2534 return ConstantInt::get(Ty, C0->usub_sat(*C1));
2535 else
2536 return ConstantInt::get(Ty, C0->ssub_sat(*C1));
2537 case Intrinsic::cttz:
2538 case Intrinsic::ctlz:
2539 assert(C1 && "Must be constant int")((C1 && "Must be constant int") ? static_cast<void
> (0) : __assert_fail ("C1 && \"Must be constant int\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/lib/Analysis/ConstantFolding.cpp"
, 2539, __PRETTY_FUNCTION__))
;
2540
2541 // cttz(0, 1) and ctlz(0, 1) are undef.
2542 if (C1->isOneValue() && (!C0 || C0->isNullValue()))
2543 return UndefValue::get(Ty);
2544 if (!C0)
2545 return Constant::getNullValue(Ty);
2546 if (IntrinsicID == Intrinsic::cttz)
2547 return ConstantInt::get(Ty, C0->countTrailingZeros());
2548 else
2549 return ConstantInt::get(Ty, C0->countLeadingZeros());
2550
2551 case Intrinsic::abs:
2552 // Undef or minimum val operand with poison min --> undef
2553 assert(C1 && "Must be constant int")((C1 && "Must be constant int") ? static_cast<void
> (0) : __assert_fail ("C1 && \"Must be constant int\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/lib/Analysis/ConstantFolding.cpp"
, 2553, __PRETTY_FUNCTION__))
;
29
'?' condition is true
2554 if (C1->isOneValue() && (!C0 || C0->isMinSignedValue()))
30
Calling 'APInt::isOneValue'
38
Returning from 'APInt::isOneValue'
2555 return UndefValue::get(Ty);
2556
2557 // Undef operand with no poison min --> 0 (sign bit must be clear)
2558 if (C1->isNullValue() && !C0)
39
Calling 'APInt::isNullValue'
49
Returning from 'APInt::isNullValue'
2559 return Constant::getNullValue(Ty);
2560
2561 return ConstantInt::get(Ty, C0->abs());
50
Called C++ object pointer is null
2562 }
2563
2564 return nullptr;
2565 }
2566
2567 // Support ConstantVector in case we have an Undef in the top.
2568 if ((isa<ConstantVector>(Operands[0]) ||
2569 isa<ConstantDataVector>(Operands[0])) &&
2570 // Check for default rounding mode.
2571 // FIXME: Support other rounding modes?
2572 isa<ConstantInt>(Operands[1]) &&
2573 cast<ConstantInt>(Operands[1])->getValue() == 4) {
2574 auto *Op = cast<Constant>(Operands[0]);
2575 switch (IntrinsicID) {
2576 default: break;
2577 case Intrinsic::x86_avx512_vcvtss2si32:
2578 case Intrinsic::x86_avx512_vcvtss2si64:
2579 case Intrinsic::x86_avx512_vcvtsd2si32:
2580 case Intrinsic::x86_avx512_vcvtsd2si64:
2581 if (ConstantFP *FPOp =
2582 dyn_cast_or_null<ConstantFP>(Op->getAggregateElement(0U)))
2583 return ConstantFoldSSEConvertToInt(FPOp->getValueAPF(),
2584 /*roundTowardZero=*/false, Ty,
2585 /*IsSigned*/true);
2586 break;
2587 case Intrinsic::x86_avx512_vcvtss2usi32:
2588 case Intrinsic::x86_avx512_vcvtss2usi64:
2589 case Intrinsic::x86_avx512_vcvtsd2usi32:
2590 case Intrinsic::x86_avx512_vcvtsd2usi64:
2591 if (ConstantFP *FPOp =
2592 dyn_cast_or_null<ConstantFP>(Op->getAggregateElement(0U)))
2593 return ConstantFoldSSEConvertToInt(FPOp->getValueAPF(),
2594 /*roundTowardZero=*/false, Ty,
2595 /*IsSigned*/false);
2596 break;
2597 case Intrinsic::x86_avx512_cvttss2si:
2598 case Intrinsic::x86_avx512_cvttss2si64:
2599 case Intrinsic::x86_avx512_cvttsd2si:
2600 case Intrinsic::x86_avx512_cvttsd2si64:
2601 if (ConstantFP *FPOp =
2602 dyn_cast_or_null<ConstantFP>(Op->getAggregateElement(0U)))
2603 return ConstantFoldSSEConvertToInt(FPOp->getValueAPF(),
2604 /*roundTowardZero=*/true, Ty,
2605 /*IsSigned*/true);
2606 break;
2607 case Intrinsic::x86_avx512_cvttss2usi:
2608 case Intrinsic::x86_avx512_cvttss2usi64:
2609 case Intrinsic::x86_avx512_cvttsd2usi:
2610 case Intrinsic::x86_avx512_cvttsd2usi64:
2611 if (ConstantFP *FPOp =
2612 dyn_cast_or_null<ConstantFP>(Op->getAggregateElement(0U)))
2613 return ConstantFoldSSEConvertToInt(FPOp->getValueAPF(),
2614 /*roundTowardZero=*/true, Ty,
2615 /*IsSigned*/false);
2616 break;
2617 }
2618 }
2619 return nullptr;
2620}
2621
2622static APFloat ConstantFoldAMDGCNCubeIntrinsic(Intrinsic::ID IntrinsicID,
2623 const APFloat &S0,
2624 const APFloat &S1,
2625 const APFloat &S2) {
2626 unsigned ID;
2627 const fltSemantics &Sem = S0.getSemantics();
2628 APFloat MA(Sem), SC(Sem), TC(Sem);
2629 if (abs(S2) >= abs(S0) && abs(S2) >= abs(S1)) {
2630 if (S2.isNegative() && S2.isNonZero() && !S2.isNaN()) {
2631 // S2 < 0
2632 ID = 5;
2633 SC = -S0;
2634 } else {
2635 ID = 4;
2636 SC = S0;
2637 }
2638 MA = S2;
2639 TC = -S1;
2640 } else if (abs(S1) >= abs(S0)) {
2641 if (S1.isNegative() && S1.isNonZero() && !S1.isNaN()) {
2642 // S1 < 0
2643 ID = 3;
2644 TC = -S2;
2645 } else {
2646 ID = 2;
2647 TC = S2;
2648 }
2649 MA = S1;
2650 SC = S0;
2651 } else {
2652 if (S0.isNegative() && S0.isNonZero() && !S0.isNaN()) {
2653 // S0 < 0
2654 ID = 1;
2655 SC = S2;
2656 } else {
2657 ID = 0;
2658 SC = -S2;
2659 }
2660 MA = S0;
2661 TC = -S1;
2662 }
2663 switch (IntrinsicID) {
2664 default:
2665 llvm_unreachable("unhandled amdgcn cube intrinsic")::llvm::llvm_unreachable_internal("unhandled amdgcn cube intrinsic"
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/lib/Analysis/ConstantFolding.cpp"
, 2665)
;
2666 case Intrinsic::amdgcn_cubeid:
2667 return APFloat(Sem, ID);
2668 case Intrinsic::amdgcn_cubema:
2669 return MA + MA;
2670 case Intrinsic::amdgcn_cubesc:
2671 return SC;
2672 case Intrinsic::amdgcn_cubetc:
2673 return TC;
2674 }
2675}
2676
2677static Constant *ConstantFoldScalarCall3(StringRef Name,
2678 Intrinsic::ID IntrinsicID,
2679 Type *Ty,
2680 ArrayRef<Constant *> Operands,
2681 const TargetLibraryInfo *TLI,
2682 const CallBase *Call) {
2683 assert(Operands.size() == 3 && "Wrong number of operands.")((Operands.size() == 3 && "Wrong number of operands."
) ? static_cast<void> (0) : __assert_fail ("Operands.size() == 3 && \"Wrong number of operands.\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/lib/Analysis/ConstantFolding.cpp"
, 2683, __PRETTY_FUNCTION__))
;
2684
2685 if (const auto *Op1 = dyn_cast<ConstantFP>(Operands[0])) {
2686 if (const auto *Op2 = dyn_cast<ConstantFP>(Operands[1])) {
2687 if (const auto *Op3 = dyn_cast<ConstantFP>(Operands[2])) {
2688 switch (IntrinsicID) {
2689 default: break;
2690 case Intrinsic::fma:
2691 case Intrinsic::fmuladd: {
2692 APFloat V = Op1->getValueAPF();
2693 V.fusedMultiplyAdd(Op2->getValueAPF(), Op3->getValueAPF(),
2694 APFloat::rmNearestTiesToEven);
2695 return ConstantFP::get(Ty->getContext(), V);
2696 }
2697 case Intrinsic::amdgcn_cubeid:
2698 case Intrinsic::amdgcn_cubema:
2699 case Intrinsic::amdgcn_cubesc:
2700 case Intrinsic::amdgcn_cubetc: {
2701 APFloat V = ConstantFoldAMDGCNCubeIntrinsic(
2702 IntrinsicID, Op1->getValueAPF(), Op2->getValueAPF(),
2703 Op3->getValueAPF());
2704 return ConstantFP::get(Ty->getContext(), V);
2705 }
2706 }
2707 }
2708 }
2709 }
2710
2711 if (const auto *Op1 = dyn_cast<ConstantInt>(Operands[0])) {
2712 if (const auto *Op2 = dyn_cast<ConstantInt>(Operands[1])) {
2713 if (const auto *Op3 = dyn_cast<ConstantInt>(Operands[2])) {
2714 switch (IntrinsicID) {
2715 default: break;
2716 case Intrinsic::smul_fix:
2717 case Intrinsic::smul_fix_sat: {
2718 // This code performs rounding towards negative infinity in case the
2719 // result cannot be represented exactly for the given scale. Targets
2720 // that do care about rounding should use a target hook for specifying
2721 // how rounding should be done, and provide their own folding to be
2722 // consistent with rounding. This is the same approach as used by
2723 // DAGTypeLegalizer::ExpandIntRes_MULFIX.
2724 const APInt &Lhs = Op1->getValue();
2725 const APInt &Rhs = Op2->getValue();
2726 unsigned Scale = Op3->getValue().getZExtValue();
2727 unsigned Width = Lhs.getBitWidth();
2728 assert(Scale < Width && "Illegal scale.")((Scale < Width && "Illegal scale.") ? static_cast
<void> (0) : __assert_fail ("Scale < Width && \"Illegal scale.\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/lib/Analysis/ConstantFolding.cpp"
, 2728, __PRETTY_FUNCTION__))
;
2729 unsigned ExtendedWidth = Width * 2;
2730 APInt Product = (Lhs.sextOrSelf(ExtendedWidth) *
2731 Rhs.sextOrSelf(ExtendedWidth)).ashr(Scale);
2732 if (IntrinsicID == Intrinsic::smul_fix_sat) {
2733 APInt MaxValue =
2734 APInt::getSignedMaxValue(Width).sextOrSelf(ExtendedWidth);
2735 APInt MinValue =
2736 APInt::getSignedMinValue(Width).sextOrSelf(ExtendedWidth);
2737 Product = APIntOps::smin(Product, MaxValue);
2738 Product = APIntOps::smax(Product, MinValue);
2739 }
2740 return ConstantInt::get(Ty->getContext(),
2741 Product.sextOrTrunc(Width));
2742 }
2743 }
2744 }
2745 }
2746 }
2747
2748 if (IntrinsicID == Intrinsic::fshl || IntrinsicID == Intrinsic::fshr) {
2749 const APInt *C0, *C1, *C2;
2750 if (!getConstIntOrUndef(Operands[0], C0) ||
2751 !getConstIntOrUndef(Operands[1], C1) ||
2752 !getConstIntOrUndef(Operands[2], C2))
2753 return nullptr;
2754
2755 bool IsRight = IntrinsicID == Intrinsic::fshr;
2756 if (!C2)
2757 return Operands[IsRight ? 1 : 0];
2758 if (!C0 && !C1)
2759 return UndefValue::get(Ty);
2760
2761 // The shift amount is interpreted as modulo the bitwidth. If the shift
2762 // amount is effectively 0, avoid UB due to oversized inverse shift below.
2763 unsigned BitWidth = C2->getBitWidth();
2764 unsigned ShAmt = C2->urem(BitWidth);
2765 if (!ShAmt)
2766 return Operands[IsRight ? 1 : 0];
2767
2768 // (C0 << ShlAmt) | (C1 >> LshrAmt)
2769 unsigned LshrAmt = IsRight ? ShAmt : BitWidth - ShAmt;
2770 unsigned ShlAmt = !IsRight ? ShAmt : BitWidth - ShAmt;
2771 if (!C0)
2772 return ConstantInt::get(Ty, C1->lshr(LshrAmt));
2773 if (!C1)
2774 return ConstantInt::get(Ty, C0->shl(ShlAmt));
2775 return ConstantInt::get(Ty, C0->shl(ShlAmt) | C1->lshr(LshrAmt));
2776 }
2777
2778 return nullptr;
2779}
2780
2781static Constant *ConstantFoldScalarCall(StringRef Name,
2782 Intrinsic::ID IntrinsicID,
2783 Type *Ty,
2784 ArrayRef<Constant *> Operands,
2785 const TargetLibraryInfo *TLI,
2786 const CallBase *Call) {
2787 if (Operands.size() == 1)
2788 return ConstantFoldScalarCall1(Name, IntrinsicID, Ty, Operands, TLI, Call);
2789
2790 if (Operands.size() == 2)
2791 return ConstantFoldScalarCall2(Name, IntrinsicID, Ty, Operands, TLI, Call);
2792
2793 if (Operands.size() == 3)
2794 return ConstantFoldScalarCall3(Name, IntrinsicID, Ty, Operands, TLI, Call);
2795
2796 return nullptr;
2797}
2798
2799static Constant *ConstantFoldVectorCall(StringRef Name,
2800 Intrinsic::ID IntrinsicID,
2801 VectorType *VTy,
2802 ArrayRef<Constant *> Operands,
2803 const DataLayout &DL,
2804 const TargetLibraryInfo *TLI,
2805 const CallBase *Call) {
2806 // Do not iterate on scalable vector. The number of elements is unknown at
2807 // compile-time.
2808 if (isa<ScalableVectorType>(VTy))
2809 return nullptr;
2810
2811 auto *FVTy = cast<FixedVectorType>(VTy);
2812
2813 SmallVector<Constant *, 4> Result(FVTy->getNumElements());
2814 SmallVector<Constant *, 4> Lane(Operands.size());
2815 Type *Ty = FVTy->getElementType();
2816
2817 switch (IntrinsicID) {
2818 case Intrinsic::masked_load: {
2819 auto *SrcPtr = Operands[0];
2820 auto *Mask = Operands[2];
2821 auto *Passthru = Operands[3];
2822
2823 Constant *VecData = ConstantFoldLoadFromConstPtr(SrcPtr, FVTy, DL);
2824
2825 SmallVector<Constant *, 32> NewElements;
2826 for (unsigned I = 0, E = FVTy->getNumElements(); I != E; ++I) {
2827 auto *MaskElt = Mask->getAggregateElement(I);
2828 if (!MaskElt)
2829 break;
2830 auto *PassthruElt = Passthru->getAggregateElement(I);
2831 auto *VecElt = VecData ? VecData->getAggregateElement(I) : nullptr;
2832 if (isa<UndefValue>(MaskElt)) {
2833 if (PassthruElt)
2834 NewElements.push_back(PassthruElt);
2835 else if (VecElt)
2836 NewElements.push_back(VecElt);
2837 else
2838 return nullptr;
2839 }
2840 if (MaskElt->isNullValue()) {
2841 if (!PassthruElt)
2842 return nullptr;
2843 NewElements.push_back(PassthruElt);
2844 } else if (MaskElt->isOneValue()) {
2845 if (!VecElt)
2846 return nullptr;
2847 NewElements.push_back(VecElt);
2848 } else {
2849 return nullptr;
2850 }
2851 }
2852 if (NewElements.size() != FVTy->getNumElements())
2853 return nullptr;
2854 return ConstantVector::get(NewElements);
2855 }
2856 case Intrinsic::arm_mve_vctp8:
2857 case Intrinsic::arm_mve_vctp16:
2858 case Intrinsic::arm_mve_vctp32:
2859 case Intrinsic::arm_mve_vctp64: {
2860 if (auto *Op = dyn_cast<ConstantInt>(Operands[0])) {
2861 unsigned Lanes = FVTy->getNumElements();
2862 uint64_t Limit = Op->getZExtValue();
2863 // vctp64 are currently modelled as returning a v4i1, not a v2i1. Make
2864 // sure we get the limit right in that case and set all relevant lanes.
2865 if (IntrinsicID == Intrinsic::arm_mve_vctp64)
2866 Limit *= 2;
2867
2868 SmallVector<Constant *, 16> NCs;
2869 for (unsigned i = 0; i < Lanes; i++) {
2870 if (i < Limit)
2871 NCs.push_back(ConstantInt::getTrue(Ty));
2872 else
2873 NCs.push_back(ConstantInt::getFalse(Ty));
2874 }
2875 return ConstantVector::get(NCs);
2876 }
2877 break;
2878 }
2879 default:
2880 break;
2881 }
2882
2883 for (unsigned I = 0, E = FVTy->getNumElements(); I != E; ++I) {
2884 // Gather a column of constants.
2885 for (unsigned J = 0, JE = Operands.size(); J != JE; ++J) {
2886 // Some intrinsics use a scalar type for certain arguments.
2887 if (hasVectorInstrinsicScalarOpd(IntrinsicID, J)) {
2888 Lane[J] = Operands[J];
2889 continue;
2890 }
2891
2892 Constant *Agg = Operands[J]->getAggregateElement(I);
2893 if (!Agg)
2894 return nullptr;
2895
2896 Lane[J] = Agg;
2897 }
2898
2899 // Use the regular scalar folding to simplify this column.
2900 Constant *Folded =
2901 ConstantFoldScalarCall(Name, IntrinsicID, Ty, Lane, TLI, Call);
2902 if (!Folded)
2903 return nullptr;
2904 Result[I] = Folded;
2905 }
2906
2907 return ConstantVector::get(Result);
2908}
2909
2910} // end anonymous namespace
2911
2912Constant *llvm::ConstantFoldCall(const CallBase *Call, Function *F,
2913 ArrayRef<Constant *> Operands,
2914 const TargetLibraryInfo *TLI) {
2915 if (Call->isNoBuiltin())
2916 return nullptr;
2917 if (!F->hasName())
2918 return nullptr;
2919 StringRef Name = F->getName();
2920
2921 Type *Ty = F->getReturnType();
2922
2923 if (auto *VTy = dyn_cast<VectorType>(Ty))
2924 return ConstantFoldVectorCall(Name, F->getIntrinsicID(), VTy, Operands,
2925 F->getParent()->getDataLayout(), TLI, Call);
2926
2927 return ConstantFoldScalarCall(Name, F->getIntrinsicID(), Ty, Operands, TLI,
2928 Call);
2929}
2930
2931bool llvm::isMathLibCallNoop(const CallBase *Call,
2932 const TargetLibraryInfo *TLI) {
2933 // FIXME: Refactor this code; this duplicates logic in LibCallsShrinkWrap
2934 // (and to some extent ConstantFoldScalarCall).
2935 if (Call->isNoBuiltin() || Call->isStrictFP())
2936 return false;
2937 Function *F = Call->getCalledFunction();
2938 if (!F)
2939 return false;
2940
2941 LibFunc Func;
2942 if (!TLI || !TLI->getLibFunc(*F, Func))
2943 return false;
2944
2945 if (Call->getNumArgOperands() == 1) {
2946 if (ConstantFP *OpC = dyn_cast<ConstantFP>(Call->getArgOperand(0))) {
2947 const APFloat &Op = OpC->getValueAPF();
2948 switch (Func) {
2949 case LibFunc_logl:
2950 case LibFunc_log:
2951 case LibFunc_logf:
2952 case LibFunc_log2l:
2953 case LibFunc_log2:
2954 case LibFunc_log2f:
2955 case LibFunc_log10l:
2956 case LibFunc_log10:
2957 case LibFunc_log10f:
2958 return Op.isNaN() || (!Op.isZero() && !Op.isNegative());
2959
2960 case LibFunc_expl:
2961 case LibFunc_exp:
2962 case LibFunc_expf:
2963 // FIXME: These boundaries are slightly conservative.
2964 if (OpC->getType()->isDoubleTy())
2965 return !(Op < APFloat(-745.0) || Op > APFloat(709.0));
2966 if (OpC->getType()->isFloatTy())
2967 return !(Op < APFloat(-103.0f) || Op > APFloat(88.0f));
2968 break;
2969
2970 case LibFunc_exp2l:
2971 case LibFunc_exp2:
2972 case LibFunc_exp2f:
2973 // FIXME: These boundaries are slightly conservative.
2974 if (OpC->getType()->isDoubleTy())
2975 return !(Op < APFloat(-1074.0) || Op > APFloat(1023.0));
2976 if (OpC->getType()->isFloatTy())
2977 return !(Op < APFloat(-149.0f) || Op > APFloat(127.0f));
2978 break;
2979
2980 case LibFunc_sinl:
2981 case LibFunc_sin:
2982 case LibFunc_sinf:
2983 case LibFunc_cosl:
2984 case LibFunc_cos:
2985 case LibFunc_cosf:
2986 return !Op.isInfinity();
2987
2988 case LibFunc_tanl:
2989 case LibFunc_tan:
2990 case LibFunc_tanf: {
2991 // FIXME: Stop using the host math library.
2992 // FIXME: The computation isn't done in the right precision.
2993 Type *Ty = OpC->getType();
2994 if (Ty->isDoubleTy() || Ty->isFloatTy() || Ty->isHalfTy()) {
2995 double OpV = getValueAsDouble(OpC);
2996 return ConstantFoldFP(tan, OpV, Ty) != nullptr;
2997 }
2998 break;
2999 }
3000
3001 case LibFunc_asinl:
3002 case LibFunc_asin:
3003 case LibFunc_asinf:
3004 case LibFunc_acosl:
3005 case LibFunc_acos:
3006 case LibFunc_acosf:
3007 return !(Op < APFloat(Op.getSemantics(), "-1") ||
3008 Op > APFloat(Op.getSemantics(), "1"));
3009
3010 case LibFunc_sinh:
3011 case LibFunc_cosh:
3012 case LibFunc_sinhf:
3013 case LibFunc_coshf:
3014 case LibFunc_sinhl:
3015 case LibFunc_coshl:
3016 // FIXME: These boundaries are slightly conservative.
3017 if (OpC->getType()->isDoubleTy())
3018 return !(Op < APFloat(-710.0) || Op > APFloat(710.0));
3019 if (OpC->getType()->isFloatTy())
3020 return !(Op < APFloat(-89.0f) || Op > APFloat(89.0f));
3021 break;
3022
3023 case LibFunc_sqrtl:
3024 case LibFunc_sqrt:
3025 case LibFunc_sqrtf:
3026 return Op.isNaN() || Op.isZero() || !Op.isNegative();
3027
3028 // FIXME: Add more functions: sqrt_finite, atanh, expm1, log1p,
3029 // maybe others?
3030 default:
3031 break;
3032 }
3033 }
3034 }
3035
3036 if (Call->getNumArgOperands() == 2) {
3037 ConstantFP *Op0C = dyn_cast<ConstantFP>(Call->getArgOperand(0));
3038 ConstantFP *Op1C = dyn_cast<ConstantFP>(Call->getArgOperand(1));
3039 if (Op0C && Op1C) {
3040 const APFloat &Op0 = Op0C->getValueAPF();
3041 const APFloat &Op1 = Op1C->getValueAPF();
3042
3043 switch (Func) {
3044 case LibFunc_powl:
3045 case LibFunc_pow:
3046 case LibFunc_powf: {
3047 // FIXME: Stop using the host math library.
3048 // FIXME: The computation isn't done in the right precision.
3049 Type *Ty = Op0C->getType();
3050 if (Ty->isDoubleTy() || Ty->isFloatTy() || Ty->isHalfTy()) {
3051 if (Ty == Op1C->getType()) {
3052 double Op0V = getValueAsDouble(Op0C);
3053 double Op1V = getValueAsDouble(Op1C);
3054 return ConstantFoldBinaryFP(pow, Op0V, Op1V, Ty) != nullptr;
3055 }
3056 }
3057 break;
3058 }
3059
3060 case LibFunc_fmodl:
3061 case LibFunc_fmod:
3062 case LibFunc_fmodf:
3063 case LibFunc_remainderl:
3064 case LibFunc_remainder:
3065 case LibFunc_remainderf:
3066 return Op0.isNaN() || Op1.isNaN() ||
3067 (!Op0.isInfinity() && !Op1.isZero());
3068
3069 default:
3070 break;
3071 }
3072 }
3073 }
3074
3075 return false;
3076}
3077
3078void TargetFolder::anchor() {}

/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/include/llvm/IR/Type.h

1//===- llvm/Type.h - Classes for handling data types ------------*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file contains the declaration of the Type class. For more "Type"
10// stuff, look in DerivedTypes.h.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef LLVM_IR_TYPE_H
15#define LLVM_IR_TYPE_H
16
17#include "llvm/ADT/APFloat.h"
18#include "llvm/ADT/ArrayRef.h"
19#include "llvm/ADT/SmallPtrSet.h"
20#include "llvm/Support/CBindingWrapping.h"
21#include "llvm/Support/Casting.h"
22#include "llvm/Support/Compiler.h"
23#include "llvm/Support/ErrorHandling.h"
24#include "llvm/Support/TypeSize.h"
25#include <cassert>
26#include <cstdint>
27#include <iterator>
28
29namespace llvm {
30
31template<class GraphType> struct GraphTraits;
32class IntegerType;
33class LLVMContext;
34class PointerType;
35class raw_ostream;
36class StringRef;
37
38/// The instances of the Type class are immutable: once they are created,
39/// they are never changed. Also note that only one instance of a particular
40/// type is ever created. Thus seeing if two types are equal is a matter of
41/// doing a trivial pointer comparison. To enforce that no two equal instances
42/// are created, Type instances can only be created via static factory methods
43/// in class Type and in derived classes. Once allocated, Types are never
44/// free'd.
45///
46class Type {
47public:
48 //===--------------------------------------------------------------------===//
49 /// Definitions of all of the base types for the Type system. Based on this
50 /// value, you can cast to a class defined in DerivedTypes.h.
51 /// Note: If you add an element to this, you need to add an element to the
52 /// Type::getPrimitiveType function, or else things will break!
53 /// Also update LLVMTypeKind and LLVMGetTypeKind () in the C binding.
54 ///
55 enum TypeID {
56 // PrimitiveTypes
57 HalfTyID = 0, ///< 16-bit floating point type
58 BFloatTyID, ///< 16-bit floating point type (7-bit significand)
59 FloatTyID, ///< 32-bit floating point type
60 DoubleTyID, ///< 64-bit floating point type
61 X86_FP80TyID, ///< 80-bit floating point type (X87)
62 FP128TyID, ///< 128-bit floating point type (112-bit significand)
63 PPC_FP128TyID, ///< 128-bit floating point type (two 64-bits, PowerPC)
64 VoidTyID, ///< type with no size
65 LabelTyID, ///< Labels
66 MetadataTyID, ///< Metadata
67 X86_MMXTyID, ///< MMX vectors (64 bits, X86 specific)
68 TokenTyID, ///< Tokens
69
70 // Derived types... see DerivedTypes.h file.
71 IntegerTyID, ///< Arbitrary bit width integers
72 FunctionTyID, ///< Functions
73 PointerTyID, ///< Pointers
74 StructTyID, ///< Structures
75 ArrayTyID, ///< Arrays
76 FixedVectorTyID, ///< Fixed width SIMD vector type
77 ScalableVectorTyID ///< Scalable SIMD vector type
78 };
79
80private:
81 /// This refers to the LLVMContext in which this type was uniqued.
82 LLVMContext &Context;
83
84 TypeID ID : 8; // The current base type of this type.
85 unsigned SubclassData : 24; // Space for subclasses to store data.
86 // Note that this should be synchronized with
87 // MAX_INT_BITS value in IntegerType class.
88
89protected:
90 friend class LLVMContextImpl;
91
92 explicit Type(LLVMContext &C, TypeID tid)
93 : Context(C), ID(tid), SubclassData(0) {}
94 ~Type() = default;
95
96 unsigned getSubclassData() const { return SubclassData; }
97
98 void setSubclassData(unsigned val) {
99 SubclassData = val;
100 // Ensure we don't have any accidental truncation.
101 assert(getSubclassData() == val && "Subclass data too large for field")((getSubclassData() == val && "Subclass data too large for field"
) ? static_cast<void> (0) : __assert_fail ("getSubclassData() == val && \"Subclass data too large for field\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/include/llvm/IR/Type.h"
, 101, __PRETTY_FUNCTION__))
;
102 }
103
104 /// Keeps track of how many Type*'s there are in the ContainedTys list.
105 unsigned NumContainedTys = 0;
106
107 /// A pointer to the array of Types contained by this Type. For example, this
108 /// includes the arguments of a function type, the elements of a structure,
109 /// the pointee of a pointer, the element type of an array, etc. This pointer
110 /// may be 0 for types that don't contain other types (Integer, Double,
111 /// Float).
112 Type * const *ContainedTys = nullptr;
113
114public:
115 /// Print the current type.
116 /// Omit the type details if \p NoDetails == true.
117 /// E.g., let %st = type { i32, i16 }
118 /// When \p NoDetails is true, we only print %st.
119 /// Put differently, \p NoDetails prints the type as if
120 /// inlined with the operands when printing an instruction.
121 void print(raw_ostream &O, bool IsForDebug = false,
122 bool NoDetails = false) const;
123
124 void dump() const;
125
126 /// Return the LLVMContext in which this type was uniqued.
127 LLVMContext &getContext() const { return Context; }
128
129 //===--------------------------------------------------------------------===//
130 // Accessors for working with types.
131 //
132
133 /// Return the type id for the type. This will return one of the TypeID enum
134 /// elements defined above.
135 TypeID getTypeID() const { return ID; }
136
137 /// Return true if this is 'void'.
138 bool isVoidTy() const { return getTypeID() == VoidTyID; }
139
140 /// Return true if this is 'half', a 16-bit IEEE fp type.
141 bool isHalfTy() const { return getTypeID() == HalfTyID; }
142
143 /// Return true if this is 'bfloat', a 16-bit bfloat type.
144 bool isBFloatTy() const { return getTypeID() == BFloatTyID; }
145
146 /// Return true if this is 'float', a 32-bit IEEE fp type.
147 bool isFloatTy() const { return getTypeID() == FloatTyID; }
148
149 /// Return true if this is 'double', a 64-bit IEEE fp type.
150 bool isDoubleTy() const { return getTypeID() == DoubleTyID; }
151
152 /// Return true if this is x86 long double.
153 bool isX86_FP80Ty() const { return getTypeID() == X86_FP80TyID; }
154
155 /// Return true if this is 'fp128'.
156 bool isFP128Ty() const { return getTypeID() == FP128TyID; }
157
158 /// Return true if this is powerpc long double.
159 bool isPPC_FP128Ty() const { return getTypeID() == PPC_FP128TyID; }
160
161 /// Return true if this is one of the six floating-point types
162 bool isFloatingPointTy() const {
163 return getTypeID() == HalfTyID || getTypeID() == BFloatTyID ||
164 getTypeID() == FloatTyID || getTypeID() == DoubleTyID ||
165 getTypeID() == X86_FP80TyID || getTypeID() == FP128TyID ||
166 getTypeID() == PPC_FP128TyID;
167 }
168
169 const fltSemantics &getFltSemantics() const {
170 switch (getTypeID()) {
171 case HalfTyID: return APFloat::IEEEhalf();
172 case BFloatTyID: return APFloat::BFloat();
173 case FloatTyID: return APFloat::IEEEsingle();
174 case DoubleTyID: return APFloat::IEEEdouble();
175 case X86_FP80TyID: return APFloat::x87DoubleExtended();
176 case FP128TyID: return APFloat::IEEEquad();
177 case PPC_FP128TyID: return APFloat::PPCDoubleDouble();
178 default: llvm_unreachable("Invalid floating type")::llvm::llvm_unreachable_internal("Invalid floating type", "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/include/llvm/IR/Type.h"
, 178)
;
179 }
180 }
181
182 /// Return true if this is X86 MMX.
183 bool isX86_MMXTy() const { return getTypeID() == X86_MMXTyID; }
184
185 /// Return true if this is a FP type or a vector of FP.
186 bool isFPOrFPVectorTy() const { return getScalarType()->isFloatingPointTy(); }
187
188 /// Return true if this is 'label'.
189 bool isLabelTy() const { return getTypeID() == LabelTyID; }
190
191 /// Return true if this is 'metadata'.
192 bool isMetadataTy() const { return getTypeID() == MetadataTyID; }
193
194 /// Return true if this is 'token'.
195 bool isTokenTy() const { return getTypeID() == TokenTyID; }
196
197 /// True if this is an instance of IntegerType.
198 bool isIntegerTy() const { return getTypeID() == IntegerTyID; }
6
Assuming the condition is true
7
Returning the value 1, which participates in a condition later
10
Assuming the condition is true
11
Returning the value 1, which participates in a condition later
199
200 /// Return true if this is an IntegerType of the given width.
201 bool isIntegerTy(unsigned Bitwidth) const;
202
203 /// Return true if this is an integer type or a vector of integer types.
204 bool isIntOrIntVectorTy() const { return getScalarType()->isIntegerTy(); }
205
206 /// Return true if this is an integer type or a vector of integer types of
207 /// the given width.
208 bool isIntOrIntVectorTy(unsigned BitWidth) const {
209 return getScalarType()->isIntegerTy(BitWidth);
210 }
211
212 /// Return true if this is an integer type or a pointer type.
213 bool isIntOrPtrTy() const { return isIntegerTy() || isPointerTy(); }
214
215 /// True if this is an instance of FunctionType.
216 bool isFunctionTy() const { return getTypeID() == FunctionTyID; }
217
218 /// True if this is an instance of StructType.
219 bool isStructTy() const { return getTypeID() == StructTyID; }
220
221 /// True if this is an instance of ArrayType.
222 bool isArrayTy() const { return getTypeID() == ArrayTyID; }
223
224 /// True if this is an instance of PointerType.
225 bool isPointerTy() const { return getTypeID() == PointerTyID; }
226
227 /// Return true if this is a pointer type or a vector of pointer types.
228 bool isPtrOrPtrVectorTy() const { return getScalarType()->isPointerTy(); }
229
230 /// True if this is an instance of VectorType.
231 inline bool isVectorTy() const {
232 return getTypeID() == ScalableVectorTyID || getTypeID() == FixedVectorTyID;
233 }
234
235 /// Return true if this type could be converted with a lossless BitCast to
236 /// type 'Ty'. For example, i8* to i32*. BitCasts are valid for types of the
237 /// same size only where no re-interpretation of the bits is done.
238 /// Determine if this type could be losslessly bitcast to Ty
239 bool canLosslesslyBitCastTo(Type *Ty) const;
240
241 /// Return true if this type is empty, that is, it has no elements or all of
242 /// its elements are empty.
243 bool isEmptyTy() const;
244
245 /// Return true if the type is "first class", meaning it is a valid type for a
246 /// Value.
247 bool isFirstClassType() const {
248 return getTypeID() != FunctionTyID && getTypeID() != VoidTyID;
249 }
250
251 /// Return true if the type is a valid type for a register in codegen. This
252 /// includes all first-class types except struct and array types.
253 bool isSingleValueType() const {
254 return isFloatingPointTy() || isX86_MMXTy() || isIntegerTy() ||
255 isPointerTy() || isVectorTy();
256 }
257
258 /// Return true if the type is an aggregate type. This means it is valid as
259 /// the first operand of an insertvalue or extractvalue instruction. This
260 /// includes struct and array types, but does not include vector types.
261 bool isAggregateType() const {
262 return getTypeID() == StructTyID || getTypeID() == ArrayTyID;
263 }
264
265 /// Return true if it makes sense to take the size of this type. To get the
266 /// actual size for a particular target, it is reasonable to use the
267 /// DataLayout subsystem to do this.
268 bool isSized(SmallPtrSetImpl<Type*> *Visited = nullptr) const {
269 // If it's a primitive, it is always sized.
270 if (getTypeID() == IntegerTyID || isFloatingPointTy() ||
271 getTypeID() == PointerTyID ||
272 getTypeID() == X86_MMXTyID)
273 return true;
274 // If it is not something that can have a size (e.g. a function or label),
275 // it doesn't have a size.
276 if (getTypeID() != StructTyID && getTypeID() != ArrayTyID && !isVectorTy())
277 return false;
278 // Otherwise we have to try harder to decide.
279 return isSizedDerivedType(Visited);
280 }
281
282 /// Return the basic size of this type if it is a primitive type. These are
283 /// fixed by LLVM and are not target-dependent.
284 /// This will return zero if the type does not have a size or is not a
285 /// primitive type.
286 ///
287 /// If this is a scalable vector type, the scalable property will be set and
288 /// the runtime size will be a positive integer multiple of the base size.
289 ///
290 /// Note that this may not reflect the size of memory allocated for an
291 /// instance of the type or the number of bytes that are written when an
292 /// instance of the type is stored to memory. The DataLayout class provides
293 /// additional query functions to provide this information.
294 ///
295 TypeSize getPrimitiveSizeInBits() const LLVM_READONLY__attribute__((__pure__));
296
297 /// If this is a vector type, return the getPrimitiveSizeInBits value for the
298 /// element type. Otherwise return the getPrimitiveSizeInBits value for this
299 /// type.
300 unsigned getScalarSizeInBits() const LLVM_READONLY__attribute__((__pure__));
301
302 /// Return the width of the mantissa of this type. This is only valid on
303 /// floating-point types. If the FP type does not have a stable mantissa (e.g.
304 /// ppc long double), this method returns -1.
305 int getFPMantissaWidth() const;
306
307 /// If this is a vector type, return the element type, otherwise return
308 /// 'this'.
309 inline Type *getScalarType() const {
310 if (isVectorTy())
311 return getContainedType(0);
312 return const_cast<Type *>(this);
313 }
314
315 //===--------------------------------------------------------------------===//
316 // Type Iteration support.
317 //
318 using subtype_iterator = Type * const *;
319
320 subtype_iterator subtype_begin() const { return ContainedTys; }
321 subtype_iterator subtype_end() const { return &ContainedTys[NumContainedTys];}
322 ArrayRef<Type*> subtypes() const {
323 return makeArrayRef(subtype_begin(), subtype_end());
324 }
325
326 using subtype_reverse_iterator = std::reverse_iterator<subtype_iterator>;
327
328 subtype_reverse_iterator subtype_rbegin() const {
329 return subtype_reverse_iterator(subtype_end());
330 }
331 subtype_reverse_iterator subtype_rend() const {
332 return subtype_reverse_iterator(subtype_begin());
333 }
334
335 /// This method is used to implement the type iterator (defined at the end of
336 /// the file). For derived types, this returns the types 'contained' in the
337 /// derived type.
338 Type *getContainedType(unsigned i) const {
339 assert(i < NumContainedTys && "Index out of range!")((i < NumContainedTys && "Index out of range!") ? static_cast
<void> (0) : __assert_fail ("i < NumContainedTys && \"Index out of range!\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/include/llvm/IR/Type.h"
, 339, __PRETTY_FUNCTION__))
;
340 return ContainedTys[i];
341 }
342
343 /// Return the number of types in the derived type.
344 unsigned getNumContainedTypes() const { return NumContainedTys; }
345
346 //===--------------------------------------------------------------------===//
347 // Helper methods corresponding to subclass methods. This forces a cast to
348 // the specified subclass and calls its accessor. "getArrayNumElements" (for
349 // example) is shorthand for cast<ArrayType>(Ty)->getNumElements(). This is
350 // only intended to cover the core methods that are frequently used, helper
351 // methods should not be added here.
352
353 inline unsigned getIntegerBitWidth() const;
354
355 inline Type *getFunctionParamType(unsigned i) const;
356 inline unsigned getFunctionNumParams() const;
357 inline bool isFunctionVarArg() const;
358
359 inline StringRef getStructName() const;
360 inline unsigned getStructNumElements() const;
361 inline Type *getStructElementType(unsigned N) const;
362
363 inline uint64_t getArrayNumElements() const;
364
365 Type *getArrayElementType() const {
366 assert(getTypeID() == ArrayTyID)((getTypeID() == ArrayTyID) ? static_cast<void> (0) : __assert_fail
("getTypeID() == ArrayTyID", "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/include/llvm/IR/Type.h"
, 366, __PRETTY_FUNCTION__))
;
367 return ContainedTys[0];
368 }
369
370 Type *getPointerElementType() const {
371 assert(getTypeID() == PointerTyID)((getTypeID() == PointerTyID) ? static_cast<void> (0) :
__assert_fail ("getTypeID() == PointerTyID", "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/include/llvm/IR/Type.h"
, 371, __PRETTY_FUNCTION__))
;
372 return ContainedTys[0];
373 }
374
375 /// Given an integer or vector type, change the lane bitwidth to NewBitwidth,
376 /// whilst keeping the old number of lanes.
377 inline Type *getWithNewBitWidth(unsigned NewBitWidth) const;
378
379 /// Given scalar/vector integer type, returns a type with elements twice as
380 /// wide as in the original type. For vectors, preserves element count.
381 inline Type *getExtendedType() const;
382
383 /// Get the address space of this pointer or pointer vector type.
384 inline unsigned getPointerAddressSpace() const;
385
386 //===--------------------------------------------------------------------===//
387 // Static members exported by the Type class itself. Useful for getting
388 // instances of Type.
389 //
390
391 /// Return a type based on an identifier.
392 static Type *getPrimitiveType(LLVMContext &C, TypeID IDNumber);
393
394 //===--------------------------------------------------------------------===//
395 // These are the builtin types that are always available.
396 //
397 static Type *getVoidTy(LLVMContext &C);
398 static Type *getLabelTy(LLVMContext &C);
399 static Type *getHalfTy(LLVMContext &C);
400 static Type *getBFloatTy(LLVMContext &C);
401 static Type *getFloatTy(LLVMContext &C);
402 static Type *getDoubleTy(LLVMContext &C);
403 static Type *getMetadataTy(LLVMContext &C);
404 static Type *getX86_FP80Ty(LLVMContext &C);
405 static Type *getFP128Ty(LLVMContext &C);
406 static Type *getPPC_FP128Ty(LLVMContext &C);
407 static Type *getX86_MMXTy(LLVMContext &C);
408 static Type *getTokenTy(LLVMContext &C);
409 static IntegerType *getIntNTy(LLVMContext &C, unsigned N);
410 static IntegerType *getInt1Ty(LLVMContext &C);
411 static IntegerType *getInt8Ty(LLVMContext &C);
412 static IntegerType *getInt16Ty(LLVMContext &C);
413 static IntegerType *getInt32Ty(LLVMContext &C);
414 static IntegerType *getInt64Ty(LLVMContext &C);
415 static IntegerType *getInt128Ty(LLVMContext &C);
416 template <typename ScalarTy> static Type *getScalarTy(LLVMContext &C) {
417 int noOfBits = sizeof(ScalarTy) * CHAR_BIT8;
418 if (std::is_integral<ScalarTy>::value) {
419 return (Type*) Type::getIntNTy(C, noOfBits);
420 } else if (std::is_floating_point<ScalarTy>::value) {
421 switch (noOfBits) {
422 case 32:
423 return Type::getFloatTy(C);
424 case 64:
425 return Type::getDoubleTy(C);
426 }
427 }
428 llvm_unreachable("Unsupported type in Type::getScalarTy")::llvm::llvm_unreachable_internal("Unsupported type in Type::getScalarTy"
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/include/llvm/IR/Type.h"
, 428)
;
429 }
430
431 //===--------------------------------------------------------------------===//
432 // Convenience methods for getting pointer types with one of the above builtin
433 // types as pointee.
434 //
435 static PointerType *getHalfPtrTy(LLVMContext &C, unsigned AS = 0);
436 static PointerType *getBFloatPtrTy(LLVMContext &C, unsigned AS = 0);
437 static PointerType *getFloatPtrTy(LLVMContext &C, unsigned AS = 0);
438 static PointerType *getDoublePtrTy(LLVMContext &C, unsigned AS = 0);
439 static PointerType *getX86_FP80PtrTy(LLVMContext &C, unsigned AS = 0);
440 static PointerType *getFP128PtrTy(LLVMContext &C, unsigned AS = 0);
441 static PointerType *getPPC_FP128PtrTy(LLVMContext &C, unsigned AS = 0);
442 static PointerType *getX86_MMXPtrTy(LLVMContext &C, unsigned AS = 0);
443 static PointerType *getIntNPtrTy(LLVMContext &C, unsigned N, unsigned AS = 0);
444 static PointerType *getInt1PtrTy(LLVMContext &C, unsigned AS = 0);
445 static PointerType *getInt8PtrTy(LLVMContext &C, unsigned AS = 0);
446 static PointerType *getInt16PtrTy(LLVMContext &C, unsigned AS = 0);
447 static PointerType *getInt32PtrTy(LLVMContext &C, unsigned AS = 0);
448 static PointerType *getInt64PtrTy(LLVMContext &C, unsigned AS = 0);
449
450 /// Return a pointer to the current type. This is equivalent to
451 /// PointerType::get(Foo, AddrSpace).
452 PointerType *getPointerTo(unsigned AddrSpace = 0) const;
453
454private:
455 /// Derived types like structures and arrays are sized iff all of the members
456 /// of the type are sized as well. Since asking for their size is relatively
457 /// uncommon, move this operation out-of-line.
458 bool isSizedDerivedType(SmallPtrSetImpl<Type*> *Visited = nullptr) const;
459};
460
461// Printing of types.
462inline raw_ostream &operator<<(raw_ostream &OS, const Type &T) {
463 T.print(OS);
464 return OS;
465}
466
467// allow isa<PointerType>(x) to work without DerivedTypes.h included.
468template <> struct isa_impl<PointerType, Type> {
469 static inline bool doit(const Type &Ty) {
470 return Ty.getTypeID() == Type::PointerTyID;
471 }
472};
473
474// Create wrappers for C Binding types (see CBindingWrapping.h).
475DEFINE_ISA_CONVERSION_FUNCTIONS(Type, LLVMTypeRef)inline Type *unwrap(LLVMTypeRef P) { return reinterpret_cast<
Type*>(P); } inline LLVMTypeRef wrap(const Type *P) { return
reinterpret_cast<LLVMTypeRef>(const_cast<Type*>(
P)); } template<typename T> inline T *unwrap(LLVMTypeRef
P) { return cast<T>(unwrap(P)); }
476
477/* Specialized opaque type conversions.
478 */
479inline Type **unwrap(LLVMTypeRef* Tys) {
480 return reinterpret_cast<Type**>(Tys);
481}
482
483inline LLVMTypeRef *wrap(Type **Tys) {
484 return reinterpret_cast<LLVMTypeRef*>(const_cast<Type**>(Tys));
485}
486
487} // end namespace llvm
488
489#endif // LLVM_IR_TYPE_H

/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/include/llvm/ADT/APInt.h

1//===-- llvm/ADT/APInt.h - For Arbitrary Precision Integer -----*- C++ -*--===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8///
9/// \file
10/// This file implements a class to represent arbitrary precision
11/// integral constant values and operations on them.
12///
13//===----------------------------------------------------------------------===//
14
15#ifndef LLVM_ADT_APINT_H
16#define LLVM_ADT_APINT_H
17
18#include "llvm/Support/Compiler.h"
19#include "llvm/Support/MathExtras.h"
20#include <cassert>
21#include <climits>
22#include <cstring>
23#include <string>
24
25namespace llvm {
26class FoldingSetNodeID;
27class StringRef;
28class hash_code;
29class raw_ostream;
30
31template <typename T> class SmallVectorImpl;
32template <typename T> class ArrayRef;
33template <typename T> class Optional;
34template <typename T> struct DenseMapInfo;
35
36class APInt;
37
38inline APInt operator-(APInt);
39
40//===----------------------------------------------------------------------===//
41// APInt Class
42//===----------------------------------------------------------------------===//
43
44/// Class for arbitrary precision integers.
45///
46/// APInt is a functional replacement for common case unsigned integer type like
47/// "unsigned", "unsigned long" or "uint64_t", but also allows non-byte-width
48/// integer sizes and large integer value types such as 3-bits, 15-bits, or more
49/// than 64-bits of precision. APInt provides a variety of arithmetic operators
50/// and methods to manipulate integer values of any bit-width. It supports both
51/// the typical integer arithmetic and comparison operations as well as bitwise
52/// manipulation.
53///
54/// The class has several invariants worth noting:
55/// * All bit, byte, and word positions are zero-based.
56/// * Once the bit width is set, it doesn't change except by the Truncate,
57/// SignExtend, or ZeroExtend operations.
58/// * All binary operators must be on APInt instances of the same bit width.
59/// Attempting to use these operators on instances with different bit
60/// widths will yield an assertion.
61/// * The value is stored canonically as an unsigned value. For operations
62/// where it makes a difference, there are both signed and unsigned variants
63/// of the operation. For example, sdiv and udiv. However, because the bit
64/// widths must be the same, operations such as Mul and Add produce the same
65/// results regardless of whether the values are interpreted as signed or
66/// not.
67/// * In general, the class tries to follow the style of computation that LLVM
68/// uses in its IR. This simplifies its use for LLVM.
69///
70class LLVM_NODISCARD[[clang::warn_unused_result]] APInt {
71public:
72 typedef uint64_t WordType;
73
74 /// This enum is used to hold the constants we needed for APInt.
75 enum : unsigned {
76 /// Byte size of a word.
77 APINT_WORD_SIZE = sizeof(WordType),
78 /// Bits in a word.
79 APINT_BITS_PER_WORD = APINT_WORD_SIZE * CHAR_BIT8
80 };
81
82 enum class Rounding {
83 DOWN,
84 TOWARD_ZERO,
85 UP,
86 };
87
88 static constexpr WordType WORDTYPE_MAX = ~WordType(0);
89
90private:
91 /// This union is used to store the integer value. When the
92 /// integer bit-width <= 64, it uses VAL, otherwise it uses pVal.
93 union {
94 uint64_t VAL; ///< Used to store the <= 64 bits integer value.
95 uint64_t *pVal; ///< Used to store the >64 bits integer value.
96 } U;
97
98 unsigned BitWidth; ///< The number of bits in this APInt.
99
100 friend struct DenseMapInfo<APInt>;
101
102 friend class APSInt;
103
104 /// Fast internal constructor
105 ///
106 /// This constructor is used only internally for speed of construction of
107 /// temporaries. It is unsafe for general use so it is not public.
108 APInt(uint64_t *val, unsigned bits) : BitWidth(bits) {
109 U.pVal = val;
110 }
111
112 /// Determine if this APInt just has one word to store value.
113 ///
114 /// \returns true if the number of bits <= 64, false otherwise.
115 bool isSingleWord() const { return BitWidth
41.1
Field 'BitWidth' is > APINT_BITS_PER_WORD
41.1
Field 'BitWidth' is > APINT_BITS_PER_WORD
41.1
Field 'BitWidth' is > APINT_BITS_PER_WORD
<= APINT_BITS_PER_WORD
; }
32
Assuming field 'BitWidth' is > APINT_BITS_PER_WORD
33
Returning zero, which participates in a condition later
42
Returning zero, which participates in a condition later
116
117 /// Determine which word a bit is in.
118 ///
119 /// \returns the word position for the specified bit position.
120 static unsigned whichWord(unsigned bitPosition) {
121 return bitPosition / APINT_BITS_PER_WORD;
122 }
123
124 /// Determine which bit in a word a bit is in.
125 ///
126 /// \returns the bit position in a word for the specified bit position
127 /// in the APInt.
128 static unsigned whichBit(unsigned bitPosition) {
129 return bitPosition % APINT_BITS_PER_WORD;
130 }
131
132 /// Get a single bit mask.
133 ///
134 /// \returns a uint64_t with only bit at "whichBit(bitPosition)" set
135 /// This method generates and returns a uint64_t (word) mask for a single
136 /// bit at a specific bit position. This is used to mask the bit in the
137 /// corresponding word.
138 static uint64_t maskBit(unsigned bitPosition) {
139 return 1ULL << whichBit(bitPosition);
140 }
141
142 /// Clear unused high order bits
143 ///
144 /// This method is used internally to clear the top "N" bits in the high order
145 /// word that are not used by the APInt. This is needed after the most
146 /// significant word is assigned a value to ensure that those bits are
147 /// zero'd out.
148 APInt &clearUnusedBits() {
149 // Compute how many bits are used in the final word
150 unsigned WordBits = ((BitWidth-1) % APINT_BITS_PER_WORD) + 1;
151
152 // Mask out the high bits.
153 uint64_t mask = WORDTYPE_MAX >> (APINT_BITS_PER_WORD - WordBits);
154 if (isSingleWord())
155 U.VAL &= mask;
156 else
157 U.pVal[getNumWords() - 1] &= mask;
158 return *this;
159 }
160
161 /// Get the word corresponding to a bit position
162 /// \returns the corresponding word for the specified bit position.
163 uint64_t getWord(unsigned bitPosition) const {
164 return isSingleWord() ? U.VAL : U.pVal[whichWord(bitPosition)];
165 }
166
167 /// Utility method to change the bit width of this APInt to new bit width,
168 /// allocating and/or deallocating as necessary. There is no guarantee on the
169 /// value of any bits upon return. Caller should populate the bits after.
170 void reallocate(unsigned NewBitWidth);
171
172 /// Convert a char array into an APInt
173 ///
174 /// \param radix 2, 8, 10, 16, or 36
175 /// Converts a string into a number. The string must be non-empty
176 /// and well-formed as a number of the given base. The bit-width
177 /// must be sufficient to hold the result.
178 ///
179 /// This is used by the constructors that take string arguments.
180 ///
181 /// StringRef::getAsInteger is superficially similar but (1) does
182 /// not assume that the string is well-formed and (2) grows the
183 /// result to hold the input.
184 void fromString(unsigned numBits, StringRef str, uint8_t radix);
185
186 /// An internal division function for dividing APInts.
187 ///
188 /// This is used by the toString method to divide by the radix. It simply
189 /// provides a more convenient form of divide for internal use since KnuthDiv
190 /// has specific constraints on its inputs. If those constraints are not met
191 /// then it provides a simpler form of divide.
192 static void divide(const WordType *LHS, unsigned lhsWords,
193 const WordType *RHS, unsigned rhsWords, WordType *Quotient,
194 WordType *Remainder);
195
196 /// out-of-line slow case for inline constructor
197 void initSlowCase(uint64_t val, bool isSigned);
198
199 /// shared code between two array constructors
200 void initFromArray(ArrayRef<uint64_t> array);
201
202 /// out-of-line slow case for inline copy constructor
203 void initSlowCase(const APInt &that);
204
205 /// out-of-line slow case for shl
206 void shlSlowCase(unsigned ShiftAmt);
207
208 /// out-of-line slow case for lshr.
209 void lshrSlowCase(unsigned ShiftAmt);
210
211 /// out-of-line slow case for ashr.
212 void ashrSlowCase(unsigned ShiftAmt);
213
214 /// out-of-line slow case for operator=
215 void AssignSlowCase(const APInt &RHS);
216
217 /// out-of-line slow case for operator==
218 bool EqualSlowCase(const APInt &RHS) const LLVM_READONLY__attribute__((__pure__));
219
220 /// out-of-line slow case for countLeadingZeros
221 unsigned countLeadingZerosSlowCase() const LLVM_READONLY__attribute__((__pure__));
222
223 /// out-of-line slow case for countLeadingOnes.
224 unsigned countLeadingOnesSlowCase() const LLVM_READONLY__attribute__((__pure__));
225
226 /// out-of-line slow case for countTrailingZeros.
227 unsigned countTrailingZerosSlowCase() const LLVM_READONLY__attribute__((__pure__));
228
229 /// out-of-line slow case for countTrailingOnes
230 unsigned countTrailingOnesSlowCase() const LLVM_READONLY__attribute__((__pure__));
231
232 /// out-of-line slow case for countPopulation
233 unsigned countPopulationSlowCase() const LLVM_READONLY__attribute__((__pure__));
234
235 /// out-of-line slow case for intersects.
236 bool intersectsSlowCase(const APInt &RHS) const LLVM_READONLY__attribute__((__pure__));
237
238 /// out-of-line slow case for isSubsetOf.
239 bool isSubsetOfSlowCase(const APInt &RHS) const LLVM_READONLY__attribute__((__pure__));
240
241 /// out-of-line slow case for setBits.
242 void setBitsSlowCase(unsigned loBit, unsigned hiBit);
243
244 /// out-of-line slow case for flipAllBits.
245 void flipAllBitsSlowCase();
246
247 /// out-of-line slow case for operator&=.
248 void AndAssignSlowCase(const APInt& RHS);
249
250 /// out-of-line slow case for operator|=.
251 void OrAssignSlowCase(const APInt& RHS);
252
253 /// out-of-line slow case for operator^=.
254 void XorAssignSlowCase(const APInt& RHS);
255
256 /// Unsigned comparison. Returns -1, 0, or 1 if this APInt is less than, equal
257 /// to, or greater than RHS.
258 int compare(const APInt &RHS) const LLVM_READONLY__attribute__((__pure__));
259
260 /// Signed comparison. Returns -1, 0, or 1 if this APInt is less than, equal
261 /// to, or greater than RHS.
262 int compareSigned(const APInt &RHS) const LLVM_READONLY__attribute__((__pure__));
263
264public:
265 /// \name Constructors
266 /// @{
267
268 /// Create a new APInt of numBits width, initialized as val.
269 ///
270 /// If isSigned is true then val is treated as if it were a signed value
271 /// (i.e. as an int64_t) and the appropriate sign extension to the bit width
272 /// will be done. Otherwise, no sign extension occurs (high order bits beyond
273 /// the range of val are zero filled).
274 ///
275 /// \param numBits the bit width of the constructed APInt
276 /// \param val the initial value of the APInt
277 /// \param isSigned how to treat signedness of val
278 APInt(unsigned numBits, uint64_t val, bool isSigned = false)
279 : BitWidth(numBits) {
280 assert(BitWidth && "bitwidth too small")((BitWidth && "bitwidth too small") ? static_cast<
void> (0) : __assert_fail ("BitWidth && \"bitwidth too small\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/include/llvm/ADT/APInt.h"
, 280, __PRETTY_FUNCTION__))
;
281 if (isSingleWord()) {
282 U.VAL = val;
283 clearUnusedBits();
284 } else {
285 initSlowCase(val, isSigned);
286 }
287 }
288
289 /// Construct an APInt of numBits width, initialized as bigVal[].
290 ///
291 /// Note that bigVal.size() can be smaller or larger than the corresponding
292 /// bit width but any extraneous bits will be dropped.
293 ///
294 /// \param numBits the bit width of the constructed APInt
295 /// \param bigVal a sequence of words to form the initial value of the APInt
296 APInt(unsigned numBits, ArrayRef<uint64_t> bigVal);
297
298 /// Equivalent to APInt(numBits, ArrayRef<uint64_t>(bigVal, numWords)), but
299 /// deprecated because this constructor is prone to ambiguity with the
300 /// APInt(unsigned, uint64_t, bool) constructor.
301 ///
302 /// If this overload is ever deleted, care should be taken to prevent calls
303 /// from being incorrectly captured by the APInt(unsigned, uint64_t, bool)
304 /// constructor.
305 APInt(unsigned numBits, unsigned numWords, const uint64_t bigVal[]);
306
307 /// Construct an APInt from a string representation.
308 ///
309 /// This constructor interprets the string \p str in the given radix. The
310 /// interpretation stops when the first character that is not suitable for the
311 /// radix is encountered, or the end of the string. Acceptable radix values
312 /// are 2, 8, 10, 16, and 36. It is an error for the value implied by the
313 /// string to require more bits than numBits.
314 ///
315 /// \param numBits the bit width of the constructed APInt
316 /// \param str the string to be interpreted
317 /// \param radix the radix to use for the conversion
318 APInt(unsigned numBits, StringRef str, uint8_t radix);
319
320 /// Simply makes *this a copy of that.
321 /// Copy Constructor.
322 APInt(const APInt &that) : BitWidth(that.BitWidth) {
323 if (isSingleWord())
324 U.VAL = that.U.VAL;
325 else
326 initSlowCase(that);
327 }
328
329 /// Move Constructor.
330 APInt(APInt &&that) : BitWidth(that.BitWidth) {
331 memcpy(&U, &that.U, sizeof(U));
332 that.BitWidth = 0;
333 }
334
335 /// Destructor.
336 ~APInt() {
337 if (needsCleanup())
338 delete[] U.pVal;
339 }
340
341 /// Default constructor that creates an uninteresting APInt
342 /// representing a 1-bit zero value.
343 ///
344 /// This is useful for object deserialization (pair this with the static
345 /// method Read).
346 explicit APInt() : BitWidth(1) { U.VAL = 0; }
347
348 /// Returns whether this instance allocated memory.
349 bool needsCleanup() const { return !isSingleWord(); }
350
351 /// Used to insert APInt objects, or objects that contain APInt objects, into
352 /// FoldingSets.
353 void Profile(FoldingSetNodeID &id) const;
354
355 /// @}
356 /// \name Value Tests
357 /// @{
358
359 /// Determine sign of this APInt.
360 ///
361 /// This tests the high bit of this APInt to determine if it is set.
362 ///
363 /// \returns true if this APInt is negative, false otherwise
364 bool isNegative() const { return (*this)[BitWidth - 1]; }
365
366 /// Determine if this APInt Value is non-negative (>= 0)
367 ///
368 /// This tests the high bit of the APInt to determine if it is unset.
369 bool isNonNegative() const { return !isNegative(); }
370
371 /// Determine if sign bit of this APInt is set.
372 ///
373 /// This tests the high bit of this APInt to determine if it is set.
374 ///
375 /// \returns true if this APInt has its sign bit set, false otherwise.
376 bool isSignBitSet() const { return (*this)[BitWidth-1]; }
377
378 /// Determine if sign bit of this APInt is clear.
379 ///
380 /// This tests the high bit of this APInt to determine if it is clear.
381 ///
382 /// \returns true if this APInt has its sign bit clear, false otherwise.
383 bool isSignBitClear() const { return !isSignBitSet(); }
384
385 /// Determine if this APInt Value is positive.
386 ///
387 /// This tests if the value of this APInt is positive (> 0). Note
388 /// that 0 is not a positive value.
389 ///
390 /// \returns true if this APInt is positive.
391 bool isStrictlyPositive() const { return isNonNegative() && !isNullValue(); }
392
393 /// Determine if this APInt Value is non-positive (<= 0).
394 ///
395 /// \returns true if this APInt is non-positive.
396 bool isNonPositive() const { return !isStrictlyPositive(); }
397
398 /// Determine if all bits are set
399 ///
400 /// This checks to see if the value has all bits of the APInt are set or not.
401 bool isAllOnesValue() const {
402 if (isSingleWord())
403 return U.VAL == WORDTYPE_MAX >> (APINT_BITS_PER_WORD - BitWidth);
404 return countTrailingOnesSlowCase() == BitWidth;
405 }
406
407 /// Determine if all bits are clear
408 ///
409 /// This checks to see if the value has all bits of the APInt are clear or
410 /// not.
411 bool isNullValue() const { return !*this; }
40
Calling 'APInt::operator!'
47
Returning from 'APInt::operator!'
48
Returning zero, which participates in a condition later
412
413 /// Determine if this is a value of 1.
414 ///
415 /// This checks to see if the value of this APInt is one.
416 bool isOneValue() const {
417 if (isSingleWord())
31
Calling 'APInt::isSingleWord'
34
Returning from 'APInt::isSingleWord'
35
Taking false branch
418 return U.VAL == 1;
419 return countLeadingZerosSlowCase() == BitWidth - 1;
36
Assuming the condition is false
37
Returning zero, which participates in a condition later
420 }
421
422 /// Determine if this is the largest unsigned value.
423 ///
424 /// This checks to see if the value of this APInt is the maximum unsigned
425 /// value for the APInt's bit width.
426 bool isMaxValue() const { return isAllOnesValue(); }
427
428 /// Determine if this is the largest signed value.
429 ///
430 /// This checks to see if the value of this APInt is the maximum signed
431 /// value for the APInt's bit width.
432 bool isMaxSignedValue() const {
433 if (isSingleWord())
434 return U.VAL == ((WordType(1) << (BitWidth - 1)) - 1);
435 return !isNegative() && countTrailingOnesSlowCase() == BitWidth - 1;
436 }
437
438 /// Determine if this is the smallest unsigned value.
439 ///
440 /// This checks to see if the value of this APInt is the minimum unsigned
441 /// value for the APInt's bit width.
442 bool isMinValue() const { return isNullValue(); }
443
444 /// Determine if this is the smallest signed value.
445 ///
446 /// This checks to see if the value of this APInt is the minimum signed
447 /// value for the APInt's bit width.
448 bool isMinSignedValue() const {
449 if (isSingleWord())
450 return U.VAL == (WordType(1) << (BitWidth - 1));
451 return isNegative() && countTrailingZerosSlowCase() == BitWidth - 1;
452 }
453
454 /// Check if this APInt has an N-bits unsigned integer value.
455 bool isIntN(unsigned N) const {
456 assert(N && "N == 0 ???")((N && "N == 0 ???") ? static_cast<void> (0) : __assert_fail
("N && \"N == 0 ???\"", "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/include/llvm/ADT/APInt.h"
, 456, __PRETTY_FUNCTION__))
;
457 return getActiveBits() <= N;
458 }
459
460 /// Check if this APInt has an N-bits signed integer value.
461 bool isSignedIntN(unsigned N) const {
462 assert(N && "N == 0 ???")((N && "N == 0 ???") ? static_cast<void> (0) : __assert_fail
("N && \"N == 0 ???\"", "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/include/llvm/ADT/APInt.h"
, 462, __PRETTY_FUNCTION__))
;
463 return getMinSignedBits() <= N;
464 }
465
466 /// Check if this APInt's value is a power of two greater than zero.
467 ///
468 /// \returns true if the argument APInt value is a power of two > 0.
469 bool isPowerOf2() const {
470 if (isSingleWord())
471 return isPowerOf2_64(U.VAL);
472 return countPopulationSlowCase() == 1;
473 }
474
475 /// Check if the APInt's value is returned by getSignMask.
476 ///
477 /// \returns true if this is the value returned by getSignMask.
478 bool isSignMask() const { return isMinSignedValue(); }
479
480 /// Convert APInt to a boolean value.
481 ///
482 /// This converts the APInt to a boolean value as a test against zero.
483 bool getBoolValue() const { return !!*this; }
484
485 /// If this value is smaller than the specified limit, return it, otherwise
486 /// return the limit value. This causes the value to saturate to the limit.
487 uint64_t getLimitedValue(uint64_t Limit = UINT64_MAX(18446744073709551615UL)) const {
488 return ugt(Limit) ? Limit : getZExtValue();
489 }
490
491 /// Check if the APInt consists of a repeated bit pattern.
492 ///
493 /// e.g. 0x01010101 satisfies isSplat(8).
494 /// \param SplatSizeInBits The size of the pattern in bits. Must divide bit
495 /// width without remainder.
496 bool isSplat(unsigned SplatSizeInBits) const;
497
498 /// \returns true if this APInt value is a sequence of \param numBits ones
499 /// starting at the least significant bit with the remainder zero.
500 bool isMask(unsigned numBits) const {
501 assert(numBits != 0 && "numBits must be non-zero")((numBits != 0 && "numBits must be non-zero") ? static_cast
<void> (0) : __assert_fail ("numBits != 0 && \"numBits must be non-zero\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/include/llvm/ADT/APInt.h"
, 501, __PRETTY_FUNCTION__))
;
502 assert(numBits <= BitWidth && "numBits out of range")((numBits <= BitWidth && "numBits out of range") ?
static_cast<void> (0) : __assert_fail ("numBits <= BitWidth && \"numBits out of range\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/include/llvm/ADT/APInt.h"
, 502, __PRETTY_FUNCTION__))
;
503 if (isSingleWord())
504 return U.VAL == (WORDTYPE_MAX >> (APINT_BITS_PER_WORD - numBits));
505 unsigned Ones = countTrailingOnesSlowCase();
506 return (numBits == Ones) &&
507 ((Ones + countLeadingZerosSlowCase()) == BitWidth);
508 }
509
510 /// \returns true if this APInt is a non-empty sequence of ones starting at
511 /// the least significant bit with the remainder zero.
512 /// Ex. isMask(0x0000FFFFU) == true.
513 bool isMask() const {
514 if (isSingleWord())
515 return isMask_64(U.VAL);
516 unsigned Ones = countTrailingOnesSlowCase();
517 return (Ones > 0) && ((Ones + countLeadingZerosSlowCase()) == BitWidth);
518 }
519
520 /// Return true if this APInt value contains a sequence of ones with
521 /// the remainder zero.
522 bool isShiftedMask() const {
523 if (isSingleWord())
524 return isShiftedMask_64(U.VAL);
525 unsigned Ones = countPopulationSlowCase();
526 unsigned LeadZ = countLeadingZerosSlowCase();
527 return (Ones + LeadZ + countTrailingZeros()) == BitWidth;
528 }
529
530 /// @}
531 /// \name Value Generators
532 /// @{
533
534 /// Gets maximum unsigned value of APInt for specific bit width.
535 static APInt getMaxValue(unsigned numBits) {
536 return getAllOnesValue(numBits);
537 }
538
539 /// Gets maximum signed value of APInt for a specific bit width.
540 static APInt getSignedMaxValue(unsigned numBits) {
541 APInt API = getAllOnesValue(numBits);
542 API.clearBit(numBits - 1);
543 return API;
544 }
545
546 /// Gets minimum unsigned value of APInt for a specific bit width.
547 static APInt getMinValue(unsigned numBits) { return APInt(numBits, 0); }
548
549 /// Gets minimum signed value of APInt for a specific bit width.
550 static APInt getSignedMinValue(unsigned numBits) {
551 APInt API(numBits, 0);
552 API.setBit(numBits - 1);
553 return API;
554 }
555
556 /// Get the SignMask for a specific bit width.
557 ///
558 /// This is just a wrapper function of getSignedMinValue(), and it helps code
559 /// readability when we want to get a SignMask.
560 static APInt getSignMask(unsigned BitWidth) {
561 return getSignedMinValue(BitWidth);
562 }
563
564 /// Get the all-ones value.
565 ///
566 /// \returns the all-ones value for an APInt of the specified bit-width.
567 static APInt getAllOnesValue(unsigned numBits) {
568 return APInt(numBits, WORDTYPE_MAX, true);
569 }
570
571 /// Get the '0' value.
572 ///
573 /// \returns the '0' value for an APInt of the specified bit-width.
574 static APInt getNullValue(unsigned numBits) { return APInt(numBits, 0); }
575
576 /// Compute an APInt containing numBits highbits from this APInt.
577 ///
578 /// Get an APInt with the same BitWidth as this APInt, just zero mask
579 /// the low bits and right shift to the least significant bit.
580 ///
581 /// \returns the high "numBits" bits of this APInt.
582 APInt getHiBits(unsigned numBits) const;
583
584 /// Compute an APInt containing numBits lowbits from this APInt.
585 ///
586 /// Get an APInt with the same BitWidth as this APInt, just zero mask
587 /// the high bits.
588 ///
589 /// \returns the low "numBits" bits of this APInt.
590 APInt getLoBits(unsigned numBits) const;
591
592 /// Return an APInt with exactly one bit set in the result.
593 static APInt getOneBitSet(unsigned numBits, unsigned BitNo) {
594 APInt Res(numBits, 0);
595 Res.setBit(BitNo);
596 return Res;
597 }
598
599 /// Get a value with a block of bits set.
600 ///
601 /// Constructs an APInt value that has a contiguous range of bits set. The
602 /// bits from loBit (inclusive) to hiBit (exclusive) will be set. All other
603 /// bits will be zero. For example, with parameters(32, 0, 16) you would get
604 /// 0x0000FFFF. Please call getBitsSetWithWrap if \p loBit may be greater than
605 /// \p hiBit.
606 ///
607 /// \param numBits the intended bit width of the result
608 /// \param loBit the index of the lowest bit set.
609 /// \param hiBit the index of the highest bit set.
610 ///
611 /// \returns An APInt value with the requested bits set.
612 static APInt getBitsSet(unsigned numBits, unsigned loBit, unsigned hiBit) {
613 assert(loBit <= hiBit && "loBit greater than hiBit")((loBit <= hiBit && "loBit greater than hiBit") ? static_cast
<void> (0) : __assert_fail ("loBit <= hiBit && \"loBit greater than hiBit\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/include/llvm/ADT/APInt.h"
, 613, __PRETTY_FUNCTION__))
;
614 APInt Res(numBits, 0);
615 Res.setBits(loBit, hiBit);
616 return Res;
617 }
618
619 /// Wrap version of getBitsSet.
620 /// If \p hiBit is bigger than \p loBit, this is same with getBitsSet.
621 /// If \p hiBit is not bigger than \p loBit, the set bits "wrap". For example,
622 /// with parameters (32, 28, 4), you would get 0xF000000F.
623 /// If \p hiBit is equal to \p loBit, you would get a result with all bits
624 /// set.
625 static APInt getBitsSetWithWrap(unsigned numBits, unsigned loBit,
626 unsigned hiBit) {
627 APInt Res(numBits, 0);
628 Res.setBitsWithWrap(loBit, hiBit);
629 return Res;
630 }
631
632 /// Get a value with upper bits starting at loBit set.
633 ///
634 /// Constructs an APInt value that has a contiguous range of bits set. The
635 /// bits from loBit (inclusive) to numBits (exclusive) will be set. All other
636 /// bits will be zero. For example, with parameters(32, 12) you would get
637 /// 0xFFFFF000.
638 ///
639 /// \param numBits the intended bit width of the result
640 /// \param loBit the index of the lowest bit to set.
641 ///
642 /// \returns An APInt value with the requested bits set.
643 static APInt getBitsSetFrom(unsigned numBits, unsigned loBit) {
644 APInt Res(numBits, 0);
645 Res.setBitsFrom(loBit);
646 return Res;
647 }
648
649 /// Get a value with high bits set
650 ///
651 /// Constructs an APInt value that has the top hiBitsSet bits set.
652 ///
653 /// \param numBits the bitwidth of the result
654 /// \param hiBitsSet the number of high-order bits set in the result.
655 static APInt getHighBitsSet(unsigned numBits, unsigned hiBitsSet) {
656 APInt Res(numBits, 0);
657 Res.setHighBits(hiBitsSet);
658 return Res;
659 }
660
661 /// Get a value with low bits set
662 ///
663 /// Constructs an APInt value that has the bottom loBitsSet bits set.
664 ///
665 /// \param numBits the bitwidth of the result
666 /// \param loBitsSet the number of low-order bits set in the result.
667 static APInt getLowBitsSet(unsigned numBits, unsigned loBitsSet) {
668 APInt Res(numBits, 0);
669 Res.setLowBits(loBitsSet);
670 return Res;
671 }
672
673 /// Return a value containing V broadcasted over NewLen bits.
674 static APInt getSplat(unsigned NewLen, const APInt &V);
675
676 /// Determine if two APInts have the same value, after zero-extending
677 /// one of them (if needed!) to ensure that the bit-widths match.
678 static bool isSameValue(const APInt &I1, const APInt &I2) {
679 if (I1.getBitWidth() == I2.getBitWidth())
680 return I1 == I2;
681
682 if (I1.getBitWidth() > I2.getBitWidth())
683 return I1 == I2.zext(I1.getBitWidth());
684
685 return I1.zext(I2.getBitWidth()) == I2;
686 }
687
688 /// Overload to compute a hash_code for an APInt value.
689 friend hash_code hash_value(const APInt &Arg);
690
691 /// This function returns a pointer to the internal storage of the APInt.
692 /// This is useful for writing out the APInt in binary form without any
693 /// conversions.
694 const uint64_t *getRawData() const {
695 if (isSingleWord())
696 return &U.VAL;
697 return &U.pVal[0];
698 }
699
700 /// @}
701 /// \name Unary Operators
702 /// @{
703
704 /// Postfix increment operator.
705 ///
706 /// Increments *this by 1.
707 ///
708 /// \returns a new APInt value representing the original value of *this.
709 const APInt operator++(int) {
710 APInt API(*this);
711 ++(*this);
712 return API;
713 }
714
715 /// Prefix increment operator.
716 ///
717 /// \returns *this incremented by one
718 APInt &operator++();
719
720 /// Postfix decrement operator.
721 ///
722 /// Decrements *this by 1.
723 ///
724 /// \returns a new APInt value representing the original value of *this.
725 const APInt operator--(int) {
726 APInt API(*this);
727 --(*this);
728 return API;
729 }
730
731 /// Prefix decrement operator.
732 ///
733 /// \returns *this decremented by one.
734 APInt &operator--();
735
736 /// Logical negation operator.
737 ///
738 /// Performs logical negation operation on this APInt.
739 ///
740 /// \returns true if *this is zero, false otherwise.
741 bool operator!() const {
742 if (isSingleWord())
41
Calling 'APInt::isSingleWord'
43
Returning from 'APInt::isSingleWord'
44
Taking false branch
743 return U.VAL == 0;
744 return countLeadingZerosSlowCase() == BitWidth;
45
Assuming the condition is false
46
Returning zero, which participates in a condition later
745 }
746
747 /// @}
748 /// \name Assignment Operators
749 /// @{
750
751 /// Copy assignment operator.
752 ///
753 /// \returns *this after assignment of RHS.
754 APInt &operator=(const APInt &RHS) {
755 // If the bitwidths are the same, we can avoid mucking with memory
756 if (isSingleWord() && RHS.isSingleWord()) {
757 U.VAL = RHS.U.VAL;
758 BitWidth = RHS.BitWidth;
759 return clearUnusedBits();
760 }
761
762 AssignSlowCase(RHS);
763 return *this;
764 }
765
766 /// Move assignment operator.
767 APInt &operator=(APInt &&that) {
768#ifdef EXPENSIVE_CHECKS
769 // Some std::shuffle implementations still do self-assignment.
770 if (this == &that)
771 return *this;
772#endif
773 assert(this != &that && "Self-move not supported")((this != &that && "Self-move not supported") ? static_cast
<void> (0) : __assert_fail ("this != &that && \"Self-move not supported\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/include/llvm/ADT/APInt.h"
, 773, __PRETTY_FUNCTION__))
;
774 if (!isSingleWord())
775 delete[] U.pVal;
776
777 // Use memcpy so that type based alias analysis sees both VAL and pVal
778 // as modified.
779 memcpy(&U, &that.U, sizeof(U));
780
781 BitWidth = that.BitWidth;
782 that.BitWidth = 0;
783
784 return *this;
785 }
786
787 /// Assignment operator.
788 ///
789 /// The RHS value is assigned to *this. If the significant bits in RHS exceed
790 /// the bit width, the excess bits are truncated. If the bit width is larger
791 /// than 64, the value is zero filled in the unspecified high order bits.
792 ///
793 /// \returns *this after assignment of RHS value.
794 APInt &operator=(uint64_t RHS) {
795 if (isSingleWord()) {
796 U.VAL = RHS;
797 return clearUnusedBits();
798 }
799 U.pVal[0] = RHS;
800 memset(U.pVal + 1, 0, (getNumWords() - 1) * APINT_WORD_SIZE);
801 return *this;
802 }
803
804 /// Bitwise AND assignment operator.
805 ///
806 /// Performs a bitwise AND operation on this APInt and RHS. The result is
807 /// assigned to *this.
808 ///
809 /// \returns *this after ANDing with RHS.
810 APInt &operator&=(const APInt &RHS) {
811 assert(BitWidth == RHS.BitWidth && "Bit widths must be the same")((BitWidth == RHS.BitWidth && "Bit widths must be the same"
) ? static_cast<void> (0) : __assert_fail ("BitWidth == RHS.BitWidth && \"Bit widths must be the same\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/include/llvm/ADT/APInt.h"
, 811, __PRETTY_FUNCTION__))
;
812 if (isSingleWord())
813 U.VAL &= RHS.U.VAL;
814 else
815 AndAssignSlowCase(RHS);
816 return *this;
817 }
818
819 /// Bitwise AND assignment operator.
820 ///
821 /// Performs a bitwise AND operation on this APInt and RHS. RHS is
822 /// logically zero-extended or truncated to match the bit-width of
823 /// the LHS.
824 APInt &operator&=(uint64_t RHS) {
825 if (isSingleWord()) {
826 U.VAL &= RHS;
827 return *this;
828 }
829 U.pVal[0] &= RHS;
830 memset(U.pVal+1, 0, (getNumWords() - 1) * APINT_WORD_SIZE);
831 return *this;
832 }
833
834 /// Bitwise OR assignment operator.
835 ///
836 /// Performs a bitwise OR operation on this APInt and RHS. The result is
837 /// assigned *this;
838 ///
839 /// \returns *this after ORing with RHS.
840 APInt &operator|=(const APInt &RHS) {
841 assert(BitWidth == RHS.BitWidth && "Bit widths must be the same")((BitWidth == RHS.BitWidth && "Bit widths must be the same"
) ? static_cast<void> (0) : __assert_fail ("BitWidth == RHS.BitWidth && \"Bit widths must be the same\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/include/llvm/ADT/APInt.h"
, 841, __PRETTY_FUNCTION__))
;
842 if (isSingleWord())
843 U.VAL |= RHS.U.VAL;
844 else
845 OrAssignSlowCase(RHS);
846 return *this;
847 }
848
849 /// Bitwise OR assignment operator.
850 ///
851 /// Performs a bitwise OR operation on this APInt and RHS. RHS is
852 /// logically zero-extended or truncated to match the bit-width of
853 /// the LHS.
854 APInt &operator|=(uint64_t RHS) {
855 if (isSingleWord()) {
856 U.VAL |= RHS;
857 return clearUnusedBits();
858 }
859 U.pVal[0] |= RHS;
860 return *this;
861 }
862
863 /// Bitwise XOR assignment operator.
864 ///
865 /// Performs a bitwise XOR operation on this APInt and RHS. The result is
866 /// assigned to *this.
867 ///
868 /// \returns *this after XORing with RHS.
869 APInt &operator^=(const APInt &RHS) {
870 assert(BitWidth == RHS.BitWidth && "Bit widths must be the same")((BitWidth == RHS.BitWidth && "Bit widths must be the same"
) ? static_cast<void> (0) : __assert_fail ("BitWidth == RHS.BitWidth && \"Bit widths must be the same\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/include/llvm/ADT/APInt.h"
, 870, __PRETTY_FUNCTION__))
;
871 if (isSingleWord())
872 U.VAL ^= RHS.U.VAL;
873 else
874 XorAssignSlowCase(RHS);
875 return *this;
876 }
877
878 /// Bitwise XOR assignment operator.
879 ///
880 /// Performs a bitwise XOR operation on this APInt and RHS. RHS is
881 /// logically zero-extended or truncated to match the bit-width of
882 /// the LHS.
883 APInt &operator^=(uint64_t RHS) {
884 if (isSingleWord()) {
885 U.VAL ^= RHS;
886 return clearUnusedBits();
887 }
888 U.pVal[0] ^= RHS;
889 return *this;
890 }
891
892 /// Multiplication assignment operator.
893 ///
894 /// Multiplies this APInt by RHS and assigns the result to *this.
895 ///
896 /// \returns *this
897 APInt &operator*=(const APInt &RHS);
898 APInt &operator*=(uint64_t RHS);
899
900 /// Addition assignment operator.
901 ///
902 /// Adds RHS to *this and assigns the result to *this.
903 ///
904 /// \returns *this
905 APInt &operator+=(const APInt &RHS);
906 APInt &operator+=(uint64_t RHS);
907
908 /// Subtraction assignment operator.
909 ///
910 /// Subtracts RHS from *this and assigns the result to *this.
911 ///
912 /// \returns *this
913 APInt &operator-=(const APInt &RHS);
914 APInt &operator-=(uint64_t RHS);
915
916 /// Left-shift assignment function.
917 ///
918 /// Shifts *this left by shiftAmt and assigns the result to *this.
919 ///
920 /// \returns *this after shifting left by ShiftAmt
921 APInt &operator<<=(unsigned ShiftAmt) {
922 assert(ShiftAmt <= BitWidth && "Invalid shift amount")((ShiftAmt <= BitWidth && "Invalid shift amount") ?
static_cast<void> (0) : __assert_fail ("ShiftAmt <= BitWidth && \"Invalid shift amount\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/include/llvm/ADT/APInt.h"
, 922, __PRETTY_FUNCTION__))
;
923 if (isSingleWord()) {
924 if (ShiftAmt == BitWidth)
925 U.VAL = 0;
926 else
927 U.VAL <<= ShiftAmt;
928 return clearUnusedBits();
929 }
930 shlSlowCase(ShiftAmt);
931 return *this;
932 }
933
934 /// Left-shift assignment function.
935 ///
936 /// Shifts *this left by shiftAmt and assigns the result to *this.
937 ///
938 /// \returns *this after shifting left by ShiftAmt
939 APInt &operator<<=(const APInt &ShiftAmt);
940
941 /// @}
942 /// \name Binary Operators
943 /// @{
944
945 /// Multiplication operator.
946 ///
947 /// Multiplies this APInt by RHS and returns the result.
948 APInt operator*(const APInt &RHS) const;
949
950 /// Left logical shift operator.
951 ///
952 /// Shifts this APInt left by \p Bits and returns the result.
953 APInt operator<<(unsigned Bits) const { return shl(Bits); }
954
955 /// Left logical shift operator.
956 ///
957 /// Shifts this APInt left by \p Bits and returns the result.
958 APInt operator<<(const APInt &Bits) const { return shl(Bits); }
959
960 /// Arithmetic right-shift function.
961 ///
962 /// Arithmetic right-shift this APInt by shiftAmt.
963 APInt ashr(unsigned ShiftAmt) const {
964 APInt R(*this);
965 R.ashrInPlace(ShiftAmt);
966 return R;
967 }
968
969 /// Arithmetic right-shift this APInt by ShiftAmt in place.
970 void ashrInPlace(unsigned ShiftAmt) {
971 assert(ShiftAmt <= BitWidth && "Invalid shift amount")((ShiftAmt <= BitWidth && "Invalid shift amount") ?
static_cast<void> (0) : __assert_fail ("ShiftAmt <= BitWidth && \"Invalid shift amount\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/include/llvm/ADT/APInt.h"
, 971, __PRETTY_FUNCTION__))
;
972 if (isSingleWord()) {
973 int64_t SExtVAL = SignExtend64(U.VAL, BitWidth);
974 if (ShiftAmt == BitWidth)
975 U.VAL = SExtVAL >> (APINT_BITS_PER_WORD - 1); // Fill with sign bit.
976 else
977 U.VAL = SExtVAL >> ShiftAmt;
978 clearUnusedBits();
979 return;
980 }
981 ashrSlowCase(ShiftAmt);
982 }
983
984 /// Logical right-shift function.
985 ///
986 /// Logical right-shift this APInt by shiftAmt.
987 APInt lshr(unsigned shiftAmt) const {
988 APInt R(*this);
989 R.lshrInPlace(shiftAmt);
990 return R;
991 }
992
993 /// Logical right-shift this APInt by ShiftAmt in place.
994 void lshrInPlace(unsigned ShiftAmt) {
995 assert(ShiftAmt <= BitWidth && "Invalid shift amount")((ShiftAmt <= BitWidth && "Invalid shift amount") ?
static_cast<void> (0) : __assert_fail ("ShiftAmt <= BitWidth && \"Invalid shift amount\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/include/llvm/ADT/APInt.h"
, 995, __PRETTY_FUNCTION__))
;
996 if (isSingleWord()) {
997 if (ShiftAmt == BitWidth)
998 U.VAL = 0;
999 else
1000 U.VAL >>= ShiftAmt;
1001 return;
1002 }
1003 lshrSlowCase(ShiftAmt);
1004 }
1005
1006 /// Left-shift function.
1007 ///
1008 /// Left-shift this APInt by shiftAmt.
1009 APInt shl(unsigned shiftAmt) const {
1010 APInt R(*this);
1011 R <<= shiftAmt;
1012 return R;
1013 }
1014
1015 /// Rotate left by rotateAmt.
1016 APInt rotl(unsigned rotateAmt) const;
1017
1018 /// Rotate right by rotateAmt.
1019 APInt rotr(unsigned rotateAmt) const;
1020
1021 /// Arithmetic right-shift function.
1022 ///
1023 /// Arithmetic right-shift this APInt by shiftAmt.
1024 APInt ashr(const APInt &ShiftAmt) const {
1025 APInt R(*this);
1026 R.ashrInPlace(ShiftAmt);
1027 return R;
1028 }
1029
1030 /// Arithmetic right-shift this APInt by shiftAmt in place.
1031 void ashrInPlace(const APInt &shiftAmt);
1032
1033 /// Logical right-shift function.
1034 ///
1035 /// Logical right-shift this APInt by shiftAmt.
1036 APInt lshr(const APInt &ShiftAmt) const {
1037 APInt R(*this);
1038 R.lshrInPlace(ShiftAmt);
1039 return R;
1040 }
1041
1042 /// Logical right-shift this APInt by ShiftAmt in place.
1043 void lshrInPlace(const APInt &ShiftAmt);
1044
1045 /// Left-shift function.
1046 ///
1047 /// Left-shift this APInt by shiftAmt.
1048 APInt shl(const APInt &ShiftAmt) const {
1049 APInt R(*this);
1050 R <<= ShiftAmt;
1051 return R;
1052 }
1053
1054 /// Rotate left by rotateAmt.
1055 APInt rotl(const APInt &rotateAmt) const;
1056
1057 /// Rotate right by rotateAmt.
1058 APInt rotr(const APInt &rotateAmt) const;
1059
1060 /// Unsigned division operation.
1061 ///
1062 /// Perform an unsigned divide operation on this APInt by RHS. Both this and
1063 /// RHS are treated as unsigned quantities for purposes of this division.
1064 ///
1065 /// \returns a new APInt value containing the division result, rounded towards
1066 /// zero.
1067 APInt udiv(const APInt &RHS) const;
1068 APInt udiv(uint64_t RHS) const;
1069
1070 /// Signed division function for APInt.
1071 ///
1072 /// Signed divide this APInt by APInt RHS.
1073 ///
1074 /// The result is rounded towards zero.
1075 APInt sdiv(const APInt &RHS) const;
1076 APInt sdiv(int64_t RHS) const;
1077
1078 /// Unsigned remainder operation.
1079 ///
1080 /// Perform an unsigned remainder operation on this APInt with RHS being the
1081 /// divisor. Both this and RHS are treated as unsigned quantities for purposes
1082 /// of this operation. Note that this is a true remainder operation and not a
1083 /// modulo operation because the sign follows the sign of the dividend which
1084 /// is *this.
1085 ///
1086 /// \returns a new APInt value containing the remainder result
1087 APInt urem(const APInt &RHS) const;
1088 uint64_t urem(uint64_t RHS) const;
1089
1090 /// Function for signed remainder operation.
1091 ///
1092 /// Signed remainder operation on APInt.
1093 APInt srem(const APInt &RHS) const;
1094 int64_t srem(int64_t RHS) const;
1095
1096 /// Dual division/remainder interface.
1097 ///
1098 /// Sometimes it is convenient to divide two APInt values and obtain both the
1099 /// quotient and remainder. This function does both operations in the same
1100 /// computation making it a little more efficient. The pair of input arguments
1101 /// may overlap with the pair of output arguments. It is safe to call
1102 /// udivrem(X, Y, X, Y), for example.
1103 static void udivrem(const APInt &LHS, const APInt &RHS, APInt &Quotient,
1104 APInt &Remainder);
1105 static void udivrem(const APInt &LHS, uint64_t RHS, APInt &Quotient,
1106 uint64_t &Remainder);
1107
1108 static void sdivrem(const APInt &LHS, const APInt &RHS, APInt &Quotient,
1109 APInt &Remainder);
1110 static void sdivrem(const APInt &LHS, int64_t RHS, APInt &Quotient,
1111 int64_t &Remainder);
1112
1113 // Operations that return overflow indicators.
1114 APInt sadd_ov(const APInt &RHS, bool &Overflow) const;
1115 APInt uadd_ov(const APInt &RHS, bool &Overflow) const;
1116 APInt ssub_ov(const APInt &RHS, bool &Overflow) const;
1117 APInt usub_ov(const APInt &RHS, bool &Overflow) const;
1118 APInt sdiv_ov(const APInt &RHS, bool &Overflow) const;
1119 APInt smul_ov(const APInt &RHS, bool &Overflow) const;
1120 APInt umul_ov(const APInt &RHS, bool &Overflow) const;
1121 APInt sshl_ov(const APInt &Amt, bool &Overflow) const;
1122 APInt ushl_ov(const APInt &Amt, bool &Overflow) const;
1123
1124 // Operations that saturate
1125 APInt sadd_sat(const APInt &RHS) const;
1126 APInt uadd_sat(const APInt &RHS) const;
1127 APInt ssub_sat(const APInt &RHS) const;
1128 APInt usub_sat(const APInt &RHS) const;
1129 APInt smul_sat(const APInt &RHS) const;
1130 APInt umul_sat(const APInt &RHS) const;
1131 APInt sshl_sat(const APInt &RHS) const;
1132 APInt ushl_sat(const APInt &RHS) const;
1133
1134 /// Array-indexing support.
1135 ///
1136 /// \returns the bit value at bitPosition
1137 bool operator[](unsigned bitPosition) const {
1138 assert(bitPosition < getBitWidth() && "Bit position out of bounds!")((bitPosition < getBitWidth() && "Bit position out of bounds!"
) ? static_cast<void> (0) : __assert_fail ("bitPosition < getBitWidth() && \"Bit position out of bounds!\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/include/llvm/ADT/APInt.h"
, 1138, __PRETTY_FUNCTION__))
;
1139 return (maskBit(bitPosition) & getWord(bitPosition)) != 0;
1140 }
1141
1142 /// @}
1143 /// \name Comparison Operators
1144 /// @{
1145
1146 /// Equality operator.
1147 ///
1148 /// Compares this APInt with RHS for the validity of the equality
1149 /// relationship.
1150 bool operator==(const APInt &RHS) const {
1151 assert(BitWidth == RHS.BitWidth && "Comparison requires equal bit widths")((BitWidth == RHS.BitWidth && "Comparison requires equal bit widths"
) ? static_cast<void> (0) : __assert_fail ("BitWidth == RHS.BitWidth && \"Comparison requires equal bit widths\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/include/llvm/ADT/APInt.h"
, 1151, __PRETTY_FUNCTION__))
;
1152 if (isSingleWord())
1153 return U.VAL == RHS.U.VAL;
1154 return EqualSlowCase(RHS);
1155 }
1156
1157 /// Equality operator.
1158 ///
1159 /// Compares this APInt with a uint64_t for the validity of the equality
1160 /// relationship.
1161 ///
1162 /// \returns true if *this == Val
1163 bool operator==(uint64_t Val) const {
1164 return (isSingleWord() || getActiveBits() <= 64) && getZExtValue() == Val;
1165 }
1166
1167 /// Equality comparison.
1168 ///
1169 /// Compares this APInt with RHS for the validity of the equality
1170 /// relationship.
1171 ///
1172 /// \returns true if *this == Val
1173 bool eq(const APInt &RHS) const { return (*this) == RHS; }
1174
1175 /// Inequality operator.
1176 ///
1177 /// Compares this APInt with RHS for the validity of the inequality
1178 /// relationship.
1179 ///
1180 /// \returns true if *this != Val
1181 bool operator!=(const APInt &RHS) const { return !((*this) == RHS); }
1182
1183 /// Inequality operator.
1184 ///
1185 /// Compares this APInt with a uint64_t for the validity of the inequality
1186 /// relationship.
1187 ///
1188 /// \returns true if *this != Val
1189 bool operator!=(uint64_t Val) const { return !((*this) == Val); }
1190
1191 /// Inequality comparison
1192 ///
1193 /// Compares this APInt with RHS for the validity of the inequality
1194 /// relationship.
1195 ///
1196 /// \returns true if *this != Val
1197 bool ne(const APInt &RHS) const { return !((*this) == RHS); }
1198
1199 /// Unsigned less than comparison
1200 ///
1201 /// Regards both *this and RHS as unsigned quantities and compares them for
1202 /// the validity of the less-than relationship.
1203 ///
1204 /// \returns true if *this < RHS when both are considered unsigned.
1205 bool ult(const APInt &RHS) const { return compare(RHS) < 0; }
1206
1207 /// Unsigned less than comparison
1208 ///
1209 /// Regards both *this as an unsigned quantity and compares it with RHS for
1210 /// the validity of the less-than relationship.
1211 ///
1212 /// \returns true if *this < RHS when considered unsigned.
1213 bool ult(uint64_t RHS) const {
1214 // Only need to check active bits if not a single word.
1215 return (isSingleWord() || getActiveBits() <= 64) && getZExtValue() < RHS;
1216 }
1217
1218 /// Signed less than comparison
1219 ///
1220 /// Regards both *this and RHS as signed quantities and compares them for
1221 /// validity of the less-than relationship.
1222 ///
1223 /// \returns true if *this < RHS when both are considered signed.
1224 bool slt(const APInt &RHS) const { return compareSigned(RHS) < 0; }
1225
1226 /// Signed less than comparison
1227 ///
1228 /// Regards both *this as a signed quantity and compares it with RHS for
1229 /// the validity of the less-than relationship.
1230 ///
1231 /// \returns true if *this < RHS when considered signed.
1232 bool slt(int64_t RHS) const {
1233 return (!isSingleWord() && getMinSignedBits() > 64) ? isNegative()
1234 : getSExtValue() < RHS;
1235 }
1236
1237 /// Unsigned less or equal comparison
1238 ///
1239 /// Regards both *this and RHS as unsigned quantities and compares them for
1240 /// validity of the less-or-equal relationship.
1241 ///
1242 /// \returns true if *this <= RHS when both are considered unsigned.
1243 bool ule(const APInt &RHS) const { return compare(RHS) <= 0; }
1244
1245 /// Unsigned less or equal comparison
1246 ///
1247 /// Regards both *this as an unsigned quantity and compares it with RHS for
1248 /// the validity of the less-or-equal relationship.
1249 ///
1250 /// \returns true if *this <= RHS when considered unsigned.
1251 bool ule(uint64_t RHS) const { return !ugt(RHS); }
1252
1253 /// Signed less or equal comparison
1254 ///
1255 /// Regards both *this and RHS as signed quantities and compares them for
1256 /// validity of the less-or-equal relationship.
1257 ///
1258 /// \returns true if *this <= RHS when both are considered signed.
1259 bool sle(const APInt &RHS) const { return compareSigned(RHS) <= 0; }
1260
1261 /// Signed less or equal comparison
1262 ///
1263 /// Regards both *this as a signed quantity and compares it with RHS for the
1264 /// validity of the less-or-equal relationship.
1265 ///
1266 /// \returns true if *this <= RHS when considered signed.
1267 bool sle(uint64_t RHS) const { return !sgt(RHS); }
1268
1269 /// Unsigned greater than comparison
1270 ///
1271 /// Regards both *this and RHS as unsigned quantities and compares them for
1272 /// the validity of the greater-than relationship.
1273 ///
1274 /// \returns true if *this > RHS when both are considered unsigned.
1275 bool ugt(const APInt &RHS) const { return !ule(RHS); }
1276
1277 /// Unsigned greater than comparison
1278 ///
1279 /// Regards both *this as an unsigned quantity and compares it with RHS for
1280 /// the validity of the greater-than relationship.
1281 ///
1282 /// \returns true if *this > RHS when considered unsigned.
1283 bool ugt(uint64_t RHS) const {
1284 // Only need to check active bits if not a single word.
1285 return (!isSingleWord() && getActiveBits() > 64) || getZExtValue() > RHS;
1286 }
1287
1288 /// Signed greater than comparison
1289 ///
1290 /// Regards both *this and RHS as signed quantities and compares them for the
1291 /// validity of the greater-than relationship.
1292 ///
1293 /// \returns true if *this > RHS when both are considered signed.
1294 bool sgt(const APInt &RHS) const { return !sle(RHS); }
1295
1296 /// Signed greater than comparison
1297 ///
1298 /// Regards both *this as a signed quantity and compares it with RHS for
1299 /// the validity of the greater-than relationship.
1300 ///
1301 /// \returns true if *this > RHS when considered signed.
1302 bool sgt(int64_t RHS) const {
1303 return (!isSingleWord() && getMinSignedBits() > 64) ? !isNegative()
1304 : getSExtValue() > RHS;
1305 }
1306
1307 /// Unsigned greater or equal comparison
1308 ///
1309 /// Regards both *this and RHS as unsigned quantities and compares them for
1310 /// validity of the greater-or-equal relationship.
1311 ///
1312 /// \returns true if *this >= RHS when both are considered unsigned.
1313 bool uge(const APInt &RHS) const { return !ult(RHS); }
1314
1315 /// Unsigned greater or equal comparison
1316 ///
1317 /// Regards both *this as an unsigned quantity and compares it with RHS for
1318 /// the validity of the greater-or-equal relationship.
1319 ///
1320 /// \returns true if *this >= RHS when considered unsigned.
1321 bool uge(uint64_t RHS) const { return !ult(RHS); }
1322
1323 /// Signed greater or equal comparison
1324 ///
1325 /// Regards both *this and RHS as signed quantities and compares them for
1326 /// validity of the greater-or-equal relationship.
1327 ///
1328 /// \returns true if *this >= RHS when both are considered signed.
1329 bool sge(const APInt &RHS) const { return !slt(RHS); }
1330
1331 /// Signed greater or equal comparison
1332 ///
1333 /// Regards both *this as a signed quantity and compares it with RHS for
1334 /// the validity of the greater-or-equal relationship.
1335 ///
1336 /// \returns true if *this >= RHS when considered signed.
1337 bool sge(int64_t RHS) const { return !slt(RHS); }
1338
1339 /// This operation tests if there are any pairs of corresponding bits
1340 /// between this APInt and RHS that are both set.
1341 bool intersects(const APInt &RHS) const {
1342 assert(BitWidth == RHS.BitWidth && "Bit widths must be the same")((BitWidth == RHS.BitWidth && "Bit widths must be the same"
) ? static_cast<void> (0) : __assert_fail ("BitWidth == RHS.BitWidth && \"Bit widths must be the same\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/include/llvm/ADT/APInt.h"
, 1342, __PRETTY_FUNCTION__))
;
1343 if (isSingleWord())
1344 return (U.VAL & RHS.U.VAL) != 0;
1345 return intersectsSlowCase(RHS);
1346 }
1347
1348 /// This operation checks that all bits set in this APInt are also set in RHS.
1349 bool isSubsetOf(const APInt &RHS) const {
1350 assert(BitWidth == RHS.BitWidth && "Bit widths must be the same")((BitWidth == RHS.BitWidth && "Bit widths must be the same"
) ? static_cast<void> (0) : __assert_fail ("BitWidth == RHS.BitWidth && \"Bit widths must be the same\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/include/llvm/ADT/APInt.h"
, 1350, __PRETTY_FUNCTION__))
;
1351 if (isSingleWord())
1352 return (U.VAL & ~RHS.U.VAL) == 0;
1353 return isSubsetOfSlowCase(RHS);
1354 }
1355
1356 /// @}
1357 /// \name Resizing Operators
1358 /// @{
1359
1360 /// Truncate to new width.
1361 ///
1362 /// Truncate the APInt to a specified width. It is an error to specify a width
1363 /// that is greater than or equal to the current width.
1364 APInt trunc(unsigned width) const;
1365
1366 /// Truncate to new width with unsigned saturation.
1367 ///
1368 /// If the APInt, treated as unsigned integer, can be losslessly truncated to
1369 /// the new bitwidth, then return truncated APInt. Else, return max value.
1370 APInt truncUSat(unsigned width) const;
1371
1372 /// Truncate to new width with signed saturation.
1373 ///
1374 /// If this APInt, treated as signed integer, can be losslessly truncated to
1375 /// the new bitwidth, then return truncated APInt. Else, return either
1376 /// signed min value if the APInt was negative, or signed max value.
1377 APInt truncSSat(unsigned width) const;
1378
1379 /// Sign extend to a new width.
1380 ///
1381 /// This operation sign extends the APInt to a new width. If the high order
1382 /// bit is set, the fill on the left will be done with 1 bits, otherwise zero.
1383 /// It is an error to specify a width that is less than or equal to the
1384 /// current width.
1385 APInt sext(unsigned width) const;
1386
1387 /// Zero extend to a new width.
1388 ///
1389 /// This operation zero extends the APInt to a new width. The high order bits
1390 /// are filled with 0 bits. It is an error to specify a width that is less
1391 /// than or equal to the current width.
1392 APInt zext(unsigned width) const;
1393
1394 /// Sign extend or truncate to width
1395 ///
1396 /// Make this APInt have the bit width given by \p width. The value is sign
1397 /// extended, truncated, or left alone to make it that width.
1398 APInt sextOrTrunc(unsigned width) const;
1399
1400 /// Zero extend or truncate to width
1401 ///
1402 /// Make this APInt have the bit width given by \p width. The value is zero
1403 /// extended, truncated, or left alone to make it that width.
1404 APInt zextOrTrunc(unsigned width) const;
1405
1406 /// Sign extend or truncate to width
1407 ///
1408 /// Make this APInt have the bit width given by \p width. The value is sign
1409 /// extended, or left alone to make it that width.
1410 APInt sextOrSelf(unsigned width) const;
1411
1412 /// Zero extend or truncate to width
1413 ///
1414 /// Make this APInt have the bit width given by \p width. The value is zero
1415 /// extended, or left alone to make it that width.
1416 APInt zextOrSelf(unsigned width) const;
1417
1418 /// @}
1419 /// \name Bit Manipulation Operators
1420 /// @{
1421
1422 /// Set every bit to 1.
1423 void setAllBits() {
1424 if (isSingleWord())
1425 U.VAL = WORDTYPE_MAX;
1426 else
1427 // Set all the bits in all the words.
1428 memset(U.pVal, -1, getNumWords() * APINT_WORD_SIZE);
1429 // Clear the unused ones
1430 clearUnusedBits();
1431 }
1432
1433 /// Set a given bit to 1.
1434 ///
1435 /// Set the given bit to 1 whose position is given as "bitPosition".
1436 void setBit(unsigned BitPosition) {
1437 assert(BitPosition < BitWidth && "BitPosition out of range")((BitPosition < BitWidth && "BitPosition out of range"
) ? static_cast<void> (0) : __assert_fail ("BitPosition < BitWidth && \"BitPosition out of range\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/include/llvm/ADT/APInt.h"
, 1437, __PRETTY_FUNCTION__))
;
1438 WordType Mask = maskBit(BitPosition);
1439 if (isSingleWord())
1440 U.VAL |= Mask;
1441 else
1442 U.pVal[whichWord(BitPosition)] |= Mask;
1443 }
1444
1445 /// Set the sign bit to 1.
1446 void setSignBit() {
1447 setBit(BitWidth - 1);
1448 }
1449
1450 /// Set a given bit to a given value.
1451 void setBitVal(unsigned BitPosition, bool BitValue) {
1452 if (BitValue)
1453 setBit(BitPosition);
1454 else
1455 clearBit(BitPosition);
1456 }
1457
1458 /// Set the bits from loBit (inclusive) to hiBit (exclusive) to 1.
1459 /// This function handles "wrap" case when \p loBit >= \p hiBit, and calls
1460 /// setBits when \p loBit < \p hiBit.
1461 /// For \p loBit == \p hiBit wrap case, set every bit to 1.
1462 void setBitsWithWrap(unsigned loBit, unsigned hiBit) {
1463 assert(hiBit <= BitWidth && "hiBit out of range")((hiBit <= BitWidth && "hiBit out of range") ? static_cast
<void> (0) : __assert_fail ("hiBit <= BitWidth && \"hiBit out of range\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/include/llvm/ADT/APInt.h"
, 1463, __PRETTY_FUNCTION__))
;
1464 assert(loBit <= BitWidth && "loBit out of range")((loBit <= BitWidth && "loBit out of range") ? static_cast
<void> (0) : __assert_fail ("loBit <= BitWidth && \"loBit out of range\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/include/llvm/ADT/APInt.h"
, 1464, __PRETTY_FUNCTION__))
;
1465 if (loBit < hiBit) {
1466 setBits(loBit, hiBit);
1467 return;
1468 }
1469 setLowBits(hiBit);
1470 setHighBits(BitWidth - loBit);
1471 }
1472
1473 /// Set the bits from loBit (inclusive) to hiBit (exclusive) to 1.
1474 /// This function handles case when \p loBit <= \p hiBit.
1475 void setBits(unsigned loBit, unsigned hiBit) {
1476 assert(hiBit <= BitWidth && "hiBit out of range")((hiBit <= BitWidth && "hiBit out of range") ? static_cast
<void> (0) : __assert_fail ("hiBit <= BitWidth && \"hiBit out of range\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/include/llvm/ADT/APInt.h"
, 1476, __PRETTY_FUNCTION__))
;
1477 assert(loBit <= BitWidth && "loBit out of range")((loBit <= BitWidth && "loBit out of range") ? static_cast
<void> (0) : __assert_fail ("loBit <= BitWidth && \"loBit out of range\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/include/llvm/ADT/APInt.h"
, 1477, __PRETTY_FUNCTION__))
;
1478 assert(loBit <= hiBit && "loBit greater than hiBit")((loBit <= hiBit && "loBit greater than hiBit") ? static_cast
<void> (0) : __assert_fail ("loBit <= hiBit && \"loBit greater than hiBit\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/include/llvm/ADT/APInt.h"
, 1478, __PRETTY_FUNCTION__))
;
1479 if (loBit == hiBit)
1480 return;
1481 if (loBit < APINT_BITS_PER_WORD && hiBit <= APINT_BITS_PER_WORD) {
1482 uint64_t mask = WORDTYPE_MAX >> (APINT_BITS_PER_WORD - (hiBit - loBit));
1483 mask <<= loBit;
1484 if (isSingleWord())
1485 U.VAL |= mask;
1486 else
1487 U.pVal[0] |= mask;
1488 } else {
1489 setBitsSlowCase(loBit, hiBit);
1490 }
1491 }
1492
1493 /// Set the top bits starting from loBit.
1494 void setBitsFrom(unsigned loBit) {
1495 return setBits(loBit, BitWidth);
1496 }
1497
1498 /// Set the bottom loBits bits.
1499 void setLowBits(unsigned loBits) {
1500 return setBits(0, loBits);
1501 }
1502
1503 /// Set the top hiBits bits.
1504 void setHighBits(unsigned hiBits) {
1505 return setBits(BitWidth - hiBits, BitWidth);
1506 }
1507
1508 /// Set every bit to 0.
1509 void clearAllBits() {
1510 if (isSingleWord())
1511 U.VAL = 0;
1512 else
1513 memset(U.pVal, 0, getNumWords() * APINT_WORD_SIZE);
1514 }
1515
1516 /// Set a given bit to 0.
1517 ///
1518 /// Set the given bit to 0 whose position is given as "bitPosition".
1519 void clearBit(unsigned BitPosition) {
1520 assert(BitPosition < BitWidth && "BitPosition out of range")((BitPosition < BitWidth && "BitPosition out of range"
) ? static_cast<void> (0) : __assert_fail ("BitPosition < BitWidth && \"BitPosition out of range\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/include/llvm/ADT/APInt.h"
, 1520, __PRETTY_FUNCTION__))
;
1521 WordType Mask = ~maskBit(BitPosition);
1522 if (isSingleWord())
1523 U.VAL &= Mask;
1524 else
1525 U.pVal[whichWord(BitPosition)] &= Mask;
1526 }
1527
1528 /// Set bottom loBits bits to 0.
1529 void clearLowBits(unsigned loBits) {
1530 assert(loBits <= BitWidth && "More bits than bitwidth")((loBits <= BitWidth && "More bits than bitwidth")
? static_cast<void> (0) : __assert_fail ("loBits <= BitWidth && \"More bits than bitwidth\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/include/llvm/ADT/APInt.h"
, 1530, __PRETTY_FUNCTION__))
;
1531 APInt Keep = getHighBitsSet(BitWidth, BitWidth - loBits);
1532 *this &= Keep;
1533 }
1534
1535 /// Set the sign bit to 0.
1536 void clearSignBit() {
1537 clearBit(BitWidth - 1);
1538 }
1539
1540 /// Toggle every bit to its opposite value.
1541 void flipAllBits() {
1542 if (isSingleWord()) {
1543 U.VAL ^= WORDTYPE_MAX;
1544 clearUnusedBits();
1545 } else {
1546 flipAllBitsSlowCase();
1547 }
1548 }
1549
1550 /// Toggles a given bit to its opposite value.
1551 ///
1552 /// Toggle a given bit to its opposite value whose position is given
1553 /// as "bitPosition".
1554 void flipBit(unsigned bitPosition);
1555
1556 /// Negate this APInt in place.
1557 void negate() {
1558 flipAllBits();
1559 ++(*this);
1560 }
1561
1562 /// Insert the bits from a smaller APInt starting at bitPosition.
1563 void insertBits(const APInt &SubBits, unsigned bitPosition);
1564 void insertBits(uint64_t SubBits, unsigned bitPosition, unsigned numBits);
1565
1566 /// Return an APInt with the extracted bits [bitPosition,bitPosition+numBits).
1567 APInt extractBits(unsigned numBits, unsigned bitPosition) const;
1568 uint64_t extractBitsAsZExtValue(unsigned numBits, unsigned bitPosition) const;
1569
1570 /// @}
1571 /// \name Value Characterization Functions
1572 /// @{
1573
1574 /// Return the number of bits in the APInt.
1575 unsigned getBitWidth() const { return BitWidth; }
1576
1577 /// Get the number of words.
1578 ///
1579 /// Here one word's bitwidth equals to that of uint64_t.
1580 ///
1581 /// \returns the number of words to hold the integer value of this APInt.
1582 unsigned getNumWords() const { return getNumWords(BitWidth); }
1583
1584 /// Get the number of words.
1585 ///
1586 /// *NOTE* Here one word's bitwidth equals to that of uint64_t.
1587 ///
1588 /// \returns the number of words to hold the integer value with a given bit
1589 /// width.
1590 static unsigned getNumWords(unsigned BitWidth) {
1591 return ((uint64_t)BitWidth + APINT_BITS_PER_WORD - 1) / APINT_BITS_PER_WORD;
1592 }
1593
1594 /// Compute the number of active bits in the value
1595 ///
1596 /// This function returns the number of active bits which is defined as the
1597 /// bit width minus the number of leading zeros. This is used in several
1598 /// computations to see how "wide" the value is.
1599 unsigned getActiveBits() const { return BitWidth - countLeadingZeros(); }
1600
1601 /// Compute the number of active words in the value of this APInt.
1602 ///
1603 /// This is used in conjunction with getActiveData to extract the raw value of
1604 /// the APInt.
1605 unsigned getActiveWords() const {
1606 unsigned numActiveBits = getActiveBits();
1607 return numActiveBits ? whichWord(numActiveBits - 1) + 1 : 1;
1608 }
1609
1610 /// Get the minimum bit size for this signed APInt
1611 ///
1612 /// Computes the minimum bit width for this APInt while considering it to be a
1613 /// signed (and probably negative) value. If the value is not negative, this
1614 /// function returns the same value as getActiveBits()+1. Otherwise, it
1615 /// returns the smallest bit width that will retain the negative value. For
1616 /// example, -1 can be written as 0b1 or 0xFFFFFFFFFF. 0b1 is shorter and so
1617 /// for -1, this function will always return 1.
1618 unsigned getMinSignedBits() const {
1619 if (isNegative())
1620 return BitWidth - countLeadingOnes() + 1;
1621 return getActiveBits() + 1;
1622 }
1623
1624 /// Get zero extended value
1625 ///
1626 /// This method attempts to return the value of this APInt as a zero extended
1627 /// uint64_t. The bitwidth must be <= 64 or the value must fit within a
1628 /// uint64_t. Otherwise an assertion will result.
1629 uint64_t getZExtValue() const {
1630 if (isSingleWord())
1631 return U.VAL;
1632 assert(getActiveBits() <= 64 && "Too many bits for uint64_t")((getActiveBits() <= 64 && "Too many bits for uint64_t"
) ? static_cast<void> (0) : __assert_fail ("getActiveBits() <= 64 && \"Too many bits for uint64_t\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/include/llvm/ADT/APInt.h"
, 1632, __PRETTY_FUNCTION__))
;
1633 return U.pVal[0];
1634 }
1635
1636 /// Get sign extended value
1637 ///
1638 /// This method attempts to return the value of this APInt as a sign extended
1639 /// int64_t. The bit width must be <= 64 or the value must fit within an
1640 /// int64_t. Otherwise an assertion will result.
1641 int64_t getSExtValue() const {
1642 if (isSingleWord())
1643 return SignExtend64(U.VAL, BitWidth);
1644 assert(getMinSignedBits() <= 64 && "Too many bits for int64_t")((getMinSignedBits() <= 64 && "Too many bits for int64_t"
) ? static_cast<void> (0) : __assert_fail ("getMinSignedBits() <= 64 && \"Too many bits for int64_t\""
, "/build/llvm-toolchain-snapshot-12~++20200917111122+b03c2b8395b/llvm/include/llvm/ADT/APInt.h"
, 1644, __PRETTY_FUNCTION__))
;
1645 return int64_t(U.pVal[0]);
1646 }
1647
1648 /// Get bits required for string value.
1649 ///
1650 /// This method determines how many bits are required to hold the APInt
1651 /// equivalent of the string given by \p str.
1652 static unsigned getBitsNeeded(StringRef str, uint8_t radix);
1653
1654 /// The APInt version of the countLeadingZeros functions in
1655 /// MathExtras.h.
1656 ///
1657 /// It counts the number of zeros from the most significant bit to the first
1658 /// one bit.
1659 ///
1660 /// \returns BitWidth if the value is zero, otherwise returns the number of
1661 /// zeros from the most significant bit to the first one bits.
1662 unsigned countLeadingZeros() const {
1663 if (isSingleWord()) {
1664 unsigned unusedBits = APINT_BITS_PER_WORD - BitWidth;
1665 return llvm::countLeadingZeros(U.VAL) - unusedBits;
1666 }
1667 return countLeadingZerosSlowCase();
1668 }
1669
1670 /// Count the number of leading one bits.
1671 ///
1672 /// This function is an APInt version of the countLeadingOnes
1673 /// functions in MathExtras.h. It counts the number of ones from the most
1674 /// significant bit to the first zero bit.
1675 ///
1676 /// \returns 0 if the high order bit is not set, otherwise returns the number
1677 /// of 1 bits from the most significant to the least
1678 unsigned countLeadingOnes() const {
1679 if (isSingleWord())
1680 return llvm::countLeadingOnes(U.VAL << (APINT_BITS_PER_WORD - BitWidth));
1681 return countLeadingOnesSlowCase();
1682 }
1683
1684 /// Computes the number of leading bits of this APInt that are equal to its
1685 /// sign bit.
1686 unsigned getNumSignBits() const {
1687 return isNegative() ? countLeadingOnes() : countLeadingZeros();
1688 }
1689
1690 /// Count the number of trailing zero bits.
1691 ///
1692 /// This function is an APInt version of the countTrailingZeros
1693 /// functions in MathExtras.h. It counts the number of zeros from the least
1694 /// significant bit to the first set bit.
1695 ///
1696 /// \returns BitWidth if the value is zero, otherwise returns the number of
1697 /// zeros from the least significant bit to the first one bit.
1698 unsigned countTrailingZeros() const {
1699 if (isSingleWord())
1700 return std::min(unsigned(llvm::countTrailingZeros(U.VAL)), BitWidth);
1701 return countTrailingZerosSlowCase();
1702 }
1703
1704 /// Count the number of trailing one bits.
1705 ///
1706 /// This function is an APInt version of the countTrailingOnes
1707 /// functions in MathExtras.h. It counts the number of ones from the least
1708 /// significant bit to the first zero bit.
1709 ///
1710 /// \returns BitWidth if the value is all ones, otherwise returns the number
1711 /// of ones from the least significant bit to the first zero bit.
1712 unsigned countTrailingOnes() const {
1713 if (isSingleWord())
1714 return llvm::countTrailingOnes(U.VAL);
1715 return countTrailingOnesSlowCase();
1716 }
1717
1718 /// Count the number of bits set.
1719 ///
1720 /// This function is an APInt version of the countPopulation functions
1721 /// in MathExtras.h. It counts the number of 1 bits in the APInt value.
1722 ///
1723 /// \returns 0 if the value is zero, otherwise returns the number of set bits.
1724 unsigned countPopulation() const {
1725 if (isSingleWord())
1726 return llvm::countPopulation(U.VAL);
1727 return countPopulationSlowCase();
1728 }
1729
1730 /// @}
1731 /// \name Conversion Functions
1732 /// @{
1733 void print(raw_ostream &OS, bool isSigned) const;
1734
1735 /// Converts an APInt to a string and append it to Str. Str is commonly a
1736 /// SmallString.
1737 void toString(SmallVectorImpl<char> &Str, unsigned Radix, bool Signed,
1738 bool formatAsCLiteral = false) const;
1739
1740 /// Considers the APInt to be unsigned and converts it into a string in the
1741 /// radix given. The radix can be 2, 8, 10 16, or 36.
1742 void toStringUnsigned(SmallVectorImpl<char> &Str, unsigned Radix = 10) const {
1743 toString(Str, Radix, false, false);
1744 }
1745
1746 /// Considers the APInt to be signed and converts it into a string in the
1747 /// radix given. The radix can be 2, 8, 10, 16, or 36.
1748 void toStringSigned(SmallVectorImpl<char> &Str, unsigned Radix = 10) const {
1749 toString(Str, Radix, true, false);
1750 }
1751
1752 /// Return the APInt as a std::string.
1753 ///
1754 /// Note that this is an inefficient method. It is better to pass in a
1755 /// SmallVector/SmallString to the methods above to avoid thrashing the heap
1756 /// for the string.
1757 std::string toString(unsigned Radix, bool Signed) const;
1758
1759 /// \returns a byte-swapped representation of this APInt Value.
1760 APInt byteSwap() const;
1761
1762 /// \returns the value with the bit representation reversed of this APInt
1763 /// Value.
1764 APInt reverseBits() const;
1765
1766 /// Converts this APInt to a double value.
1767 double roundToDouble(bool isSigned) const;
1768
1769 /// Converts this unsigned APInt to a double value.
1770 double roundToDouble() const { return roundToDouble(false); }
1771
1772 /// Converts this signed APInt to a double value.
1773 double signedRoundToDouble() const { return roundToDouble(true); }
1774
1775 /// Converts APInt bits to a double
1776 ///
1777 /// The conversion does not do a translation from integer to double, it just
1778 /// re-interprets the bits as a double. Note that it is valid to do this on
1779 /// any bit width. Exactly 64 bits will be translated.
1780 double bitsToDouble() const {
1781 return BitsToDouble(getWord(0));
1782 }
1783
1784 /// Converts APInt bits to a float
1785 ///
1786 /// The conversion does not do a translation from integer to float, it just
1787 /// re-interprets the bits as a float. Note that it is valid to do this on
1788 /// any bit width. Exactly 32 bits will be translated.
1789 float bitsToFloat() const {
1790 return BitsToFloat(static_cast<uint32_t>(getWord(0)));
1791 }
1792
1793 /// Converts a double to APInt bits.
1794 ///
1795 /// The conversion does not do a translation from double to integer, it just
1796 /// re-interprets the bits of the double.
1797 static APInt doubleToBits(double V) {
1798 return APInt(sizeof(double) * CHAR_BIT8, DoubleToBits(V));
1799 }
1800
1801 /// Converts a float to APInt bits.
1802 ///
1803 /// The conversion does not do a translation from float to integer, it just
1804 /// re-interprets the bits of the float.
1805 static APInt floatToBits(float V) {
1806 return APInt(sizeof(float) * CHAR_BIT8, FloatToBits(V));
1807 }
1808
1809 /// @}
1810 /// \name Mathematics Operations
1811 /// @{
1812
1813 /// \returns the floor log base 2 of this APInt.
1814 unsigned logBase2() const { return getActiveBits() - 1; }
1815
1816 /// \returns the ceil log base 2 of this APInt.
1817 unsigned ceilLogBase2() const {
1818 APInt temp(*this);
1819 --temp;
1820 return temp.getActiveBits();
1821 }
1822
1823 /// \returns the nearest log base 2 of this APInt. Ties round up.
1824 ///
1825 /// NOTE: When we have a BitWidth of 1, we define:
1826 ///
1827 /// log2(0) = UINT32_MAX
1828 /// log2(1) = 0
1829 ///
1830 /// to get around any mathematical concerns resulting from
1831 /// referencing 2 in a space where 2 does no exist.
1832 unsigned nearestLogBase2() const {
1833 // Special case when we have a bitwidth of 1. If VAL is 1, then we
1834 // get 0. If VAL is 0, we get WORDTYPE_MAX which gets truncated to
1835 // UINT32_MAX.
1836 if (BitWidth == 1)
1837 return U.VAL - 1;
1838
1839 // Handle the zero case.
1840 if (isNullValue())
1841 return UINT32_MAX(4294967295U);
1842
1843 // The non-zero case is handled by computing:
1844 //
1845 // nearestLogBase2(x) = logBase2(x) + x[logBase2(x)-1].
1846 //
1847 // where x[i] is referring to the value of the ith bit of x.
1848 unsigned lg = logBase2();
1849 return lg + unsigned((*this)[lg - 1]);
1850 }
1851
1852 /// \returns the log base 2 of this APInt if its an exact power of two, -1
1853 /// otherwise
1854 int32_t exactLogBase2() const {
1855 if (!isPowerOf2())
1856 return -1;
1857 return logBase2();
1858 }
1859
1860 /// Compute the square root
1861 APInt sqrt() const;
1862
1863 /// Get the absolute value;
1864 ///
1865 /// If *this is < 0 then return -(*this), otherwise *this;
1866 APInt abs() const {
1867 if (isNegative())
1868 return -(*this);
1869 return *this;
1870 }
1871
1872 /// \returns the multiplicative inverse for a given modulo.
1873 APInt multiplicativeInverse(const APInt &modulo) const;
1874
1875 /// @}
1876 /// \name Support for division by constant
1877 /// @{
1878
1879 /// Calculate the magic number for signed division by a constant.
1880 struct ms;
1881 ms magic() const;
1882
1883 /// Calculate the magic number for unsigned division by a constant.
1884 struct mu;
1885 mu magicu(unsigned LeadingZeros = 0) const;
1886
1887 /// @}
1888 /// \name Building-block Operations for APInt and APFloat
1889 /// @{
1890
1891 // These building block operations operate on a representation of arbitrary
1892 // precision, two's-complement, bignum integer values. They should be
1893 // sufficient to implement APInt and APFloat bignum requirements. Inputs are
1894 // generally a pointer to the base of an array of integer parts, representing
1895 // an unsigned bignum, and a count of how many parts there are.
1896
1897 /// Sets the least significant part of a bignum to the input value, and zeroes
1898 /// out higher parts.
1899 static void tcSet(WordType *, WordType, unsigned);
1900
1901 /// Assign one bignum to another.
1902 static void tcAssign(WordType *, const WordType *, unsigned);
1903
1904 /// Returns true if a bignum is zero, false otherwise.
1905 static bool tcIsZero(const WordType *, unsigned);
1906
1907 /// Extract the given bit of a bignum; returns 0 or 1. Zero-based.
1908 static int tcExtractBit(const WordType *, unsigned bit);
1909
1910 /// Copy the bit vector of width srcBITS from SRC, starting at bit srcLSB, to
1911 /// DST, of dstCOUNT parts, such that the bit srcLSB becomes the least
1912 /// significant bit of DST. All high bits above srcBITS in DST are
1913 /// zero-filled.
1914 static void tcExtract(WordType *, unsigned dstCount,
1915 const WordType *, unsigned srcBits,
1916 unsigned srcLSB);
1917
1918 /// Set the given bit of a bignum. Zero-based.
1919 static void tcSetBit(WordType *, unsigned bit);
1920
1921 /// Clear the given bit of a bignum. Zero-based.
1922 static void tcClearBit(WordType *, unsigned bit);
1923
1924 /// Returns the bit number of the least or most significant set bit of a
1925 /// number. If the input number has no bits set -1U is returned.
1926 static unsigned tcLSB(const WordType *, unsigned n);
1927 static unsigned tcMSB(const WordType *parts, unsigned n);
1928
1929 /// Negate a bignum in-place.
1930 static void tcNegate(WordType *, unsigned);
1931
1932 /// DST += RHS + CARRY where CARRY is zero or one. Returns the carry flag.
1933 static WordType tcAdd(WordType *, const WordType *,
1934 WordType carry, unsigned);
1935 /// DST += RHS. Returns the carry flag.
1936 static WordType tcAddPart(WordType *, WordType, unsigned);
1937
1938 /// DST -= RHS + CARRY where CARRY is zero or one. Returns the carry flag.
1939 static WordType tcSubtract(WordType *, const WordType *,
1940 WordType carry, unsigned);
1941 /// DST -= RHS. Returns the carry flag.
1942 static WordType tcSubtractPart(WordType *, WordType, unsigned);
1943
1944 /// DST += SRC * MULTIPLIER + PART if add is true
1945 /// DST = SRC * MULTIPLIER + PART if add is false
1946 ///
1947 /// Requires 0 <= DSTPARTS <= SRCPARTS + 1. If DST overlaps SRC they must
1948 /// start at the same point, i.e. DST == SRC.
1949 ///
1950 /// If DSTPARTS == SRC_PARTS + 1 no overflow occurs and zero is returned.
1951 /// Otherwise DST is filled with the least significant DSTPARTS parts of the
1952 /// result, and if all of the omitted higher parts were zero return zero,
1953 /// otherwise overflow occurred and return one.
1954 static int tcMultiplyPart(WordType *dst, const WordType *src,
1955 WordType multiplier, WordType carry,
1956 unsigned srcParts, unsigned dstParts,
1957 bool add);
1958
1959 /// DST = LHS * RHS, where DST has the same width as the operands and is
1960 /// filled with the least significant parts of the result. Returns one if
1961 /// overflow occurred, otherwise zero. DST must be disjoint from both
1962 /// operands.
1963 static int tcMultiply(WordType *, const WordType *, const WordType *,
1964 unsigned);
1965
1966 /// DST = LHS * RHS, where DST has width the sum of the widths of the
1967 /// operands. No overflow occurs. DST must be disjoint from both operands.
1968 static void tcFullMultiply(WordType *, const WordType *,
1969 const WordType *, unsigned, unsigned);
1970
1971 /// If RHS is zero LHS and REMAINDER are left unchanged, return one.
1972 /// Otherwise set LHS to LHS / RHS with the fractional part discarded, set
1973 /// REMAINDER to the remainder, return zero. i.e.
1974 ///
1975 /// OLD_LHS = RHS * LHS + REMAINDER
1976 ///
1977 /// SCRATCH is a bignum of the same size as the operands and result for use by
1978 /// the routine; its contents need not be initialized and are destroyed. LHS,
1979 /// REMAINDER and SCRATCH must be distinct.
1980 static int tcDivide(WordType *lhs, const WordType *rhs,
1981 WordType *remainder, WordType *scratch,
1982 unsigned parts);
1983
1984 /// Shift a bignum left Count bits. Shifted in bits are zero. There are no
1985 /// restrictions on Count.
1986 static void tcShiftLeft(WordType *, unsigned Words, unsigned Count);
1987
1988 /// Shift a bignum right Count bits. Shifted in bits are zero. There are no
1989 /// restrictions on Count.
1990 static void tcShiftRight(WordType *, unsigned Words, unsigned Count);
1991
1992 /// The obvious AND, OR and XOR and complement operations.
1993 static void tcAnd(WordType *, const WordType *, unsigned);
1994 static void tcOr(WordType *, const WordType *, unsigned);
1995 static void tcXor(WordType *, const WordType *, unsigned);
1996 static void tcComplement(WordType *, unsigned);
1997
1998 /// Comparison (unsigned) of two bignums.
1999 static int tcCompare(const WordType *, const WordType *, unsigned);
2000
2001 /// Increment a bignum in-place. Return the carry flag.
2002 static WordType tcIncrement(WordType *dst, unsigned parts) {
2003 return tcAddPart(dst, 1, parts);
2004 }
2005
2006 /// Decrement a bignum in-place. Return the borrow flag.
2007 static WordType tcDecrement(WordType *dst, unsigned parts) {
2008 return tcSubtractPart(dst, 1, parts);
2009 }
2010
2011 /// Set the least significant BITS and clear the rest.
2012 static void tcSetLeastSignificantBits(WordType *, unsigned, unsigned bits);
2013
2014 /// debug method
2015 void dump() const;
2016
2017 /// @}
2018};
2019
2020/// Magic data for optimising signed division by a constant.
2021struct APInt::ms {
2022 APInt m; ///< magic number
2023 unsigned s; ///< shift amount
2024};
2025
2026/// Magic data for optimising unsigned division by a constant.
2027struct APInt::mu {
2028 APInt m; ///< magic number
2029 bool a; ///< add indicator
2030 unsigned s; ///< shift amount
2031};
2032
2033inline bool operator==(uint64_t V1, const APInt &V2) { return V2 == V1; }
2034
2035inline bool operator!=(uint64_t V1, const APInt &V2) { return V2 != V1; }
2036
2037/// Unary bitwise complement operator.
2038///
2039/// \returns an APInt that is the bitwise complement of \p v.
2040inline APInt operator~(APInt v) {
2041 v.flipAllBits();
2042 return v;
2043}
2044
2045inline APInt operator&(APInt a, const APInt &b) {
2046 a &= b;
2047 return a;
2048}
2049
2050inline APInt operator&(const APInt &a, APInt &&b) {
2051 b &= a;
2052 return std::move(b);
2053}
2054
2055inline APInt operator&(APInt a, uint64_t RHS) {
2056 a &= RHS;
2057 return a;
2058}
2059
2060inline APInt operator&(uint64_t LHS, APInt b) {
2061 b &= LHS;
2062 return b;
2063}
2064
2065inline APInt operator|(APInt a, const APInt &b) {
2066 a |= b;
2067 return a;
2068}
2069
2070inline APInt operator|(const APInt &a, APInt &&b) {
2071 b |= a;
2072 return std::move(b);
2073}
2074
2075inline APInt operator|(APInt a, uint64_t RHS) {
2076 a |= RHS;
2077 return a;
2078}
2079
2080inline APInt operator|(uint64_t LHS, APInt b) {
2081 b |= LHS;
2082 return b;
2083}
2084
2085inline APInt operator^(APInt a, const APInt &b) {
2086 a ^= b;
2087 return a;
2088}
2089
2090inline APInt operator^(const APInt &a, APInt &&b) {
2091 b ^= a;
2092 return std::move(b);
2093}
2094
2095inline APInt operator^(APInt a, uint64_t RHS) {
2096 a ^= RHS;
2097 return a;
2098}
2099
2100inline APInt operator^(uint64_t LHS, APInt b) {
2101 b ^= LHS;
2102 return b;
2103}
2104
2105inline raw_ostream &operator<<(raw_ostream &OS, const APInt &I) {
2106 I.print(OS, true);
2107 return OS;
2108}
2109
2110inline APInt operator-(APInt v) {
2111 v.negate();
2112 return v;
2113}
2114
2115inline APInt operator+(APInt a, const APInt &b) {
2116 a += b;
2117 return a;
2118}
2119
2120inline APInt operator+(const APInt &a, APInt &&b) {
2121 b += a;
2122 return std::move(b);
2123}
2124
2125inline APInt operator+(APInt a, uint64_t RHS) {
2126 a += RHS;
2127 return a;
2128}
2129
2130inline APInt operator+(uint64_t LHS, APInt b) {
2131 b += LHS;
2132 return b;
2133}
2134
2135inline APInt operator-(APInt a, const APInt &b) {
2136 a -= b;
2137 return a;
2138}
2139
2140inline APInt operator-(const APInt &a, APInt &&b) {
2141 b.negate();
2142 b += a;
2143 return std::move(b);
2144}
2145
2146inline APInt operator-(APInt a, uint64_t RHS) {
2147 a -= RHS;
2148 return a;
2149}
2150
2151inline APInt operator-(uint64_t LHS, APInt b) {
2152 b.negate();
2153 b += LHS;
2154 return b;
2155}
2156
2157inline APInt operator*(APInt a, uint64_t RHS) {
2158 a *= RHS;
2159 return a;
2160}
2161
2162inline APInt operator*(uint64_t LHS, APInt b) {
2163 b *= LHS;
2164 return b;
2165}
2166
2167
2168namespace APIntOps {
2169
2170/// Determine the smaller of two APInts considered to be signed.
2171inline const APInt &smin(const APInt &A, const APInt &B) {
2172 return A.slt(B) ? A : B;
2173}
2174
2175/// Determine the larger of two APInts considered to be signed.
2176inline const APInt &smax(const APInt &A, const APInt &B) {
2177 return A.sgt(B) ? A : B;
2178}
2179
2180/// Determine the smaller of two APInts considered to be signed.
2181inline const APInt &umin(const APInt &A, const APInt &B) {
2182 return A.ult(B) ? A : B;
2183}
2184
2185/// Determine the larger of two APInts considered to be unsigned.
2186inline const APInt &umax(const APInt &A, const APInt &B) {
2187 return A.ugt(B) ? A : B;
2188}
2189
2190/// Compute GCD of two unsigned APInt values.
2191///
2192/// This function returns the greatest common divisor of the two APInt values
2193/// using Stein's algorithm.
2194///
2195/// \returns the greatest common divisor of A and B.
2196APInt GreatestCommonDivisor(APInt A, APInt B);
2197
2198/// Converts the given APInt to a double value.
2199///
2200/// Treats the APInt as an unsigned value for conversion purposes.
2201inline double RoundAPIntToDouble(const APInt &APIVal) {
2202 return APIVal.roundToDouble();
2203}
2204
2205/// Converts the given APInt to a double value.
2206///
2207/// Treats the APInt as a signed value for conversion purposes.
2208inline double RoundSignedAPIntToDouble(const APInt &APIVal) {
2209 return APIVal.signedRoundToDouble();
2210}
2211
2212/// Converts the given APInt to a float vlalue.
2213inline float RoundAPIntToFloat(const APInt &APIVal) {
2214 return float(RoundAPIntToDouble(APIVal));
2215}
2216
2217/// Converts the given APInt to a float value.
2218///
2219/// Treats the APInt as a signed value for conversion purposes.
2220inline float RoundSignedAPIntToFloat(const APInt &APIVal) {
2221 return float(APIVal.signedRoundToDouble());
2222}
2223
2224/// Converts the given double value into a APInt.
2225///
2226/// This function convert a double value to an APInt value.
2227APInt RoundDoubleToAPInt(double Double, unsigned width);
2228
2229/// Converts a float value into a APInt.
2230///
2231/// Converts a float value into an APInt value.
2232inline APInt RoundFloatToAPInt(float Float, unsigned width) {
2233 return RoundDoubleToAPInt(double(Float), width);
2234}
2235
2236/// Return A unsign-divided by B, rounded by the given rounding mode.
2237APInt RoundingUDiv(const APInt &A, const APInt &B, APInt::Rounding RM);
2238
2239/// Return A sign-divided by B, rounded by the given rounding mode.
2240APInt RoundingSDiv(const APInt &A, const APInt &B, APInt::Rounding RM);
2241
2242/// Let q(n) = An^2 + Bn + C, and BW = bit width of the value range
2243/// (e.g. 32 for i32).
2244/// This function finds the smallest number n, such that
2245/// (a) n >= 0 and q(n) = 0, or
2246/// (b) n >= 1 and q(n-1) and q(n), when evaluated in the set of all
2247/// integers, belong to two different intervals [Rk, Rk+R),
2248/// where R = 2^BW, and k is an integer.
2249/// The idea here is to find when q(n) "overflows" 2^BW, while at the
2250/// same time "allowing" subtraction. In unsigned modulo arithmetic a
2251/// subtraction (treated as addition of negated numbers) would always
2252/// count as an overflow, but here we want to allow values to decrease
2253/// and increase as long as they are within the same interval.
2254/// Specifically, adding of two negative numbers should not cause an
2255/// overflow (as long as the magnitude does not exceed the bit width).
2256/// On the other hand, given a positive number, adding a negative
2257/// number to it can give a negative result, which would cause the
2258/// value to go from [-2^BW, 0) to [0, 2^BW). In that sense, zero is
2259/// treated as a special case of an overflow.
2260///
2261/// This function returns None if after finding k that minimizes the
2262/// positive solution to q(n) = kR, both solutions are contained between
2263/// two consecutive integers.
2264///
2265/// There are cases where q(n) > T, and q(n+1) < T (assuming evaluation
2266/// in arithmetic modulo 2^BW, and treating the values as signed) by the
2267/// virtue of *signed* overflow. This function will *not* find such an n,
2268/// however it may find a value of n satisfying the inequalities due to
2269/// an *unsigned* overflow (if the values are treated as unsigned).
2270/// To find a solution for a signed overflow, treat it as a problem of
2271/// finding an unsigned overflow with a range with of BW-1.
2272///
2273/// The returned value may have a different bit width from the input
2274/// coefficients.
2275Optional<APInt> SolveQuadraticEquationWrap(APInt A, APInt B, APInt C,
2276 unsigned RangeWidth);
2277
2278/// Compare two values, and if they are different, return the position of the
2279/// most significant bit that is different in the values.
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