LLVM 20.0.0git
BPFCheckAndAdjustIR.cpp
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1//===------------ BPFCheckAndAdjustIR.cpp - Check and Adjust IR -----------===//
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// Check IR and adjust IR for verifier friendly codes.
10// The following are done for IR checking:
11// - no relocation globals in PHI node.
12// The following are done for IR adjustment:
13// - remove __builtin_bpf_passthrough builtins. Target independent IR
14// optimizations are done and those builtins can be removed.
15// - remove llvm.bpf.getelementptr.and.load builtins.
16// - remove llvm.bpf.getelementptr.and.store builtins.
17// - for loads and stores with base addresses from non-zero address space
18// cast base address to zero address space (support for BPF address spaces).
19//
20//===----------------------------------------------------------------------===//
21
22#include "BPF.h"
23#include "BPFCORE.h"
24#include "BPFTargetMachine.h"
28#include "llvm/IR/IRBuilder.h"
29#include "llvm/IR/Instruction.h"
31#include "llvm/IR/IntrinsicsBPF.h"
32#include "llvm/IR/Module.h"
33#include "llvm/IR/Type.h"
34#include "llvm/IR/User.h"
35#include "llvm/IR/Value.h"
36#include "llvm/Pass.h"
38
39#define DEBUG_TYPE "bpf-check-and-opt-ir"
40
41using namespace llvm;
42
43namespace {
44
45class BPFCheckAndAdjustIR final : public ModulePass {
46 bool runOnModule(Module &F) override;
47
48public:
49 static char ID;
50 BPFCheckAndAdjustIR() : ModulePass(ID) {}
51 virtual void getAnalysisUsage(AnalysisUsage &AU) const override;
52
53private:
54 void checkIR(Module &M);
55 bool adjustIR(Module &M);
56 bool removePassThroughBuiltin(Module &M);
57 bool removeCompareBuiltin(Module &M);
58 bool sinkMinMax(Module &M);
59 bool removeGEPBuiltins(Module &M);
60 bool insertASpaceCasts(Module &M);
61};
62} // End anonymous namespace
63
64char BPFCheckAndAdjustIR::ID = 0;
65INITIALIZE_PASS(BPFCheckAndAdjustIR, DEBUG_TYPE, "BPF Check And Adjust IR",
66 false, false)
67
69 return new BPFCheckAndAdjustIR();
70}
71
72void BPFCheckAndAdjustIR::checkIR(Module &M) {
73 // Ensure relocation global won't appear in PHI node
74 // This may happen if the compiler generated the following code:
75 // B1:
76 // g1 = @llvm.skb_buff:0:1...
77 // ...
78 // goto B_COMMON
79 // B2:
80 // g2 = @llvm.skb_buff:0:2...
81 // ...
82 // goto B_COMMON
83 // B_COMMON:
84 // g = PHI(g1, g2)
85 // x = load g
86 // ...
87 // If anything likes the above "g = PHI(g1, g2)", issue a fatal error.
88 for (Function &F : M)
89 for (auto &BB : F)
90 for (auto &I : BB) {
91 PHINode *PN = dyn_cast<PHINode>(&I);
92 if (!PN || PN->use_empty())
93 continue;
94 for (int i = 0, e = PN->getNumIncomingValues(); i < e; ++i) {
95 auto *GV = dyn_cast<GlobalVariable>(PN->getIncomingValue(i));
96 if (!GV)
97 continue;
98 if (GV->hasAttribute(BPFCoreSharedInfo::AmaAttr) ||
99 GV->hasAttribute(BPFCoreSharedInfo::TypeIdAttr))
100 report_fatal_error("relocation global in PHI node");
101 }
102 }
103}
104
105bool BPFCheckAndAdjustIR::removePassThroughBuiltin(Module &M) {
106 // Remove __builtin_bpf_passthrough()'s which are used to prevent
107 // certain IR optimizations. Now major IR optimizations are done,
108 // remove them.
109 bool Changed = false;
110 CallInst *ToBeDeleted = nullptr;
111 for (Function &F : M)
112 for (auto &BB : F)
113 for (auto &I : BB) {
114 if (ToBeDeleted) {
115 ToBeDeleted->eraseFromParent();
116 ToBeDeleted = nullptr;
117 }
118
119 auto *Call = dyn_cast<CallInst>(&I);
120 if (!Call)
121 continue;
122 auto *GV = dyn_cast<GlobalValue>(Call->getCalledOperand());
123 if (!GV)
124 continue;
125 if (!GV->getName().starts_with("llvm.bpf.passthrough"))
126 continue;
127 Changed = true;
128 Value *Arg = Call->getArgOperand(1);
129 Call->replaceAllUsesWith(Arg);
130 ToBeDeleted = Call;
131 }
132 return Changed;
133}
134
135bool BPFCheckAndAdjustIR::removeCompareBuiltin(Module &M) {
136 // Remove __builtin_bpf_compare()'s which are used to prevent
137 // certain IR optimizations. Now major IR optimizations are done,
138 // remove them.
139 bool Changed = false;
140 CallInst *ToBeDeleted = nullptr;
141 for (Function &F : M)
142 for (auto &BB : F)
143 for (auto &I : BB) {
144 if (ToBeDeleted) {
145 ToBeDeleted->eraseFromParent();
146 ToBeDeleted = nullptr;
147 }
148
149 auto *Call = dyn_cast<CallInst>(&I);
150 if (!Call)
151 continue;
152 auto *GV = dyn_cast<GlobalValue>(Call->getCalledOperand());
153 if (!GV)
154 continue;
155 if (!GV->getName().starts_with("llvm.bpf.compare"))
156 continue;
157
158 Changed = true;
159 Value *Arg0 = Call->getArgOperand(0);
160 Value *Arg1 = Call->getArgOperand(1);
161 Value *Arg2 = Call->getArgOperand(2);
162
163 auto OpVal = cast<ConstantInt>(Arg0)->getValue().getZExtValue();
165
166 auto *ICmp = new ICmpInst(Opcode, Arg1, Arg2);
167 ICmp->insertBefore(Call);
168
169 Call->replaceAllUsesWith(ICmp);
170 ToBeDeleted = Call;
171 }
172 return Changed;
173}
174
182
184 : ICmp(ICmp), Other(Other), Predicate(Predicate), MinMax(nullptr),
185 ZExt(nullptr), SExt(nullptr) {}
186};
187
189 const std::function<bool(Instruction *)> &Filter) {
190 // Check if V is:
191 // (fn %a %b) or (ext (fn %a %b))
192 // Where:
193 // ext := sext | zext
194 // fn := smin | umin | smax | umax
195 auto IsMinMaxCall = [=](Value *V, MinMaxSinkInfo &Info) {
196 if (auto *ZExt = dyn_cast<ZExtInst>(V)) {
197 V = ZExt->getOperand(0);
198 Info.ZExt = ZExt;
199 } else if (auto *SExt = dyn_cast<SExtInst>(V)) {
200 V = SExt->getOperand(0);
201 Info.SExt = SExt;
202 }
203
204 auto *Call = dyn_cast<CallInst>(V);
205 if (!Call)
206 return false;
207
208 auto *Called = dyn_cast<Function>(Call->getCalledOperand());
209 if (!Called)
210 return false;
211
212 switch (Called->getIntrinsicID()) {
213 case Intrinsic::smin:
214 case Intrinsic::umin:
215 case Intrinsic::smax:
216 case Intrinsic::umax:
217 break;
218 default:
219 return false;
220 }
221
222 if (!Filter(Call))
223 return false;
224
225 Info.MinMax = Call;
226
227 return true;
228 };
229
230 auto ZeroOrSignExtend = [](IRBuilder<> &Builder, Value *V,
232 if (Info.SExt) {
233 if (Info.SExt->getType() == V->getType())
234 return V;
235 return Builder.CreateSExt(V, Info.SExt->getType());
236 }
237 if (Info.ZExt) {
238 if (Info.ZExt->getType() == V->getType())
239 return V;
240 return Builder.CreateZExt(V, Info.ZExt->getType());
241 }
242 return V;
243 };
244
245 bool Changed = false;
247
248 // Check BB for instructions like:
249 // insn := (icmp %a (fn ...)) | (icmp (fn ...) %a)
250 //
251 // Where:
252 // fn := min | max | (sext (min ...)) | (sext (max ...))
253 //
254 // Put such instructions to SinkList.
255 for (Instruction &I : BB) {
256 ICmpInst *ICmp = dyn_cast<ICmpInst>(&I);
257 if (!ICmp)
258 continue;
259 if (!ICmp->isRelational())
260 continue;
261 MinMaxSinkInfo First(ICmp, ICmp->getOperand(1),
262 ICmpInst::getSwappedPredicate(ICmp->getPredicate()));
263 MinMaxSinkInfo Second(ICmp, ICmp->getOperand(0), ICmp->getPredicate());
264 bool FirstMinMax = IsMinMaxCall(ICmp->getOperand(0), First);
265 bool SecondMinMax = IsMinMaxCall(ICmp->getOperand(1), Second);
266 if (!(FirstMinMax ^ SecondMinMax))
267 continue;
268 SinkList.push_back(FirstMinMax ? First : Second);
269 }
270
271 // Iterate SinkList and replace each (icmp ...) with corresponding
272 // `x < a && x < b` or similar expression.
273 for (auto &Info : SinkList) {
274 ICmpInst *ICmp = Info.ICmp;
275 CallInst *MinMax = Info.MinMax;
276 Intrinsic::ID IID = MinMax->getCalledFunction()->getIntrinsicID();
277 ICmpInst::Predicate P = Info.Predicate;
278 if (ICmpInst::isSigned(P) && IID != Intrinsic::smin &&
279 IID != Intrinsic::smax)
280 continue;
281
282 IRBuilder<> Builder(ICmp);
283 Value *X = Info.Other;
284 Value *A = ZeroOrSignExtend(Builder, MinMax->getArgOperand(0), Info);
285 Value *B = ZeroOrSignExtend(Builder, MinMax->getArgOperand(1), Info);
286 bool IsMin = IID == Intrinsic::smin || IID == Intrinsic::umin;
287 bool IsMax = IID == Intrinsic::smax || IID == Intrinsic::umax;
288 bool IsLess = ICmpInst::isLE(P) || ICmpInst::isLT(P);
289 bool IsGreater = ICmpInst::isGE(P) || ICmpInst::isGT(P);
290 assert(IsMin ^ IsMax);
291 assert(IsLess ^ IsGreater);
292
293 Value *Replacement;
294 Value *LHS = Builder.CreateICmp(P, X, A);
295 Value *RHS = Builder.CreateICmp(P, X, B);
296 if ((IsLess && IsMin) || (IsGreater && IsMax))
297 // x < min(a, b) -> x < a && x < b
298 // x > max(a, b) -> x > a && x > b
299 Replacement = Builder.CreateLogicalAnd(LHS, RHS);
300 else
301 // x > min(a, b) -> x > a || x > b
302 // x < max(a, b) -> x < a || x < b
303 Replacement = Builder.CreateLogicalOr(LHS, RHS);
304
305 ICmp->replaceAllUsesWith(Replacement);
306
307 Instruction *ToRemove[] = {ICmp, Info.ZExt, Info.SExt, MinMax};
308 for (Instruction *I : ToRemove)
309 if (I && I->use_empty())
310 I->eraseFromParent();
311
312 Changed = true;
313 }
314
315 return Changed;
316}
317
318// Do the following transformation:
319//
320// x < min(a, b) -> x < a && x < b
321// x > min(a, b) -> x > a || x > b
322// x < max(a, b) -> x < a || x < b
323// x > max(a, b) -> x > a && x > b
324//
325// Such patterns are introduced by LICM.cpp:hoistMinMax()
326// transformation and might lead to BPF verification failures for
327// older kernels.
328//
329// To minimize "collateral" changes only do it for icmp + min/max
330// calls when icmp is inside a loop and min/max is outside of that
331// loop.
332//
333// Verification failure happens when:
334// - RHS operand of some `icmp LHS, RHS` is replaced by some RHS1;
335// - verifier can recognize RHS as a constant scalar in some context;
336// - verifier can't recognize RHS1 as a constant scalar in the same
337// context;
338//
339// The "constant scalar" is not a compile time constant, but a register
340// that holds a scalar value known to verifier at some point in time
341// during abstract interpretation.
342//
343// See also:
344// https://lore.kernel.org/bpf/20230406164505.1046801-1-yhs@fb.com/
345bool BPFCheckAndAdjustIR::sinkMinMax(Module &M) {
346 bool Changed = false;
347
348 for (Function &F : M) {
349 if (F.isDeclaration())
350 continue;
351
352 LoopInfo &LI = getAnalysis<LoopInfoWrapperPass>(F).getLoopInfo();
353 for (Loop *L : LI)
354 for (BasicBlock *BB : L->blocks()) {
355 // Filter out instructions coming from the same loop
356 Loop *BBLoop = LI.getLoopFor(BB);
357 auto OtherLoopFilter = [&](Instruction *I) {
358 return LI.getLoopFor(I->getParent()) != BBLoop;
359 };
360 Changed |= sinkMinMaxInBB(*BB, OtherLoopFilter);
361 }
362 }
363
364 return Changed;
365}
366
367void BPFCheckAndAdjustIR::getAnalysisUsage(AnalysisUsage &AU) const {
369}
370
371static void unrollGEPLoad(CallInst *Call) {
373 GEP->insertBefore(Call);
374 Load->insertBefore(Call);
375 Call->replaceAllUsesWith(Load);
376 Call->eraseFromParent();
377}
378
379static void unrollGEPStore(CallInst *Call) {
381 GEP->insertBefore(Call);
382 Store->insertBefore(Call);
383 Call->eraseFromParent();
384}
385
388 SmallVector<CallInst *> GEPStores;
389 for (auto &BB : F)
390 for (auto &Insn : BB)
391 if (auto *Call = dyn_cast<CallInst>(&Insn))
392 if (auto *Called = Call->getCalledFunction())
393 switch (Called->getIntrinsicID()) {
394 case Intrinsic::bpf_getelementptr_and_load:
395 GEPLoads.push_back(Call);
396 break;
397 case Intrinsic::bpf_getelementptr_and_store:
398 GEPStores.push_back(Call);
399 break;
400 }
401
402 if (GEPLoads.empty() && GEPStores.empty())
403 return false;
404
405 for_each(GEPLoads, unrollGEPLoad);
406 for_each(GEPStores, unrollGEPStore);
407
408 return true;
409}
410
411// Rewrites the following builtins:
412// - llvm.bpf.getelementptr.and.load
413// - llvm.bpf.getelementptr.and.store
414// As (load (getelementptr ...)) or (store (getelementptr ...)).
415bool BPFCheckAndAdjustIR::removeGEPBuiltins(Module &M) {
416 bool Changed = false;
417 for (auto &F : M)
418 Changed = removeGEPBuiltinsInFunc(F) || Changed;
419 return Changed;
420}
421
422// Wrap ToWrap with cast to address space zero:
423// - if ToWrap is a getelementptr,
424// wrap it's base pointer instead and return a copy;
425// - if ToWrap is Instruction, insert address space cast
426// immediately after ToWrap;
427// - if ToWrap is not an Instruction (function parameter
428// or a global value), insert address space cast at the
429// beginning of the Function F;
430// - use Cache to avoid inserting too many casts;
432 Value *ToWrap) {
433 auto It = Cache.find(ToWrap);
434 if (It != Cache.end())
435 return It->getSecond();
436
437 if (auto *GEP = dyn_cast<GetElementPtrInst>(ToWrap)) {
438 Value *Ptr = GEP->getPointerOperand();
439 Value *WrappedPtr = aspaceWrapValue(Cache, F, Ptr);
440 auto *GEPTy = cast<PointerType>(GEP->getType());
441 auto *NewGEP = GEP->clone();
442 NewGEP->insertAfter(GEP);
443 NewGEP->mutateType(GEPTy->getPointerTo(0));
444 NewGEP->setOperand(GEP->getPointerOperandIndex(), WrappedPtr);
445 NewGEP->setName(GEP->getName());
446 Cache[ToWrap] = NewGEP;
447 return NewGEP;
448 }
449
450 IRBuilder IB(F->getContext());
451 if (Instruction *InsnPtr = dyn_cast<Instruction>(ToWrap))
452 IB.SetInsertPoint(*InsnPtr->getInsertionPointAfterDef());
453 else
454 IB.SetInsertPoint(F->getEntryBlock().getFirstInsertionPt());
455 auto *PtrTy = cast<PointerType>(ToWrap->getType());
456 auto *ASZeroPtrTy = PtrTy->getPointerTo(0);
457 auto *ACast = IB.CreateAddrSpaceCast(ToWrap, ASZeroPtrTy, ToWrap->getName());
458 Cache[ToWrap] = ACast;
459 return ACast;
460}
461
462// Wrap a pointer operand OpNum of instruction I
463// with cast to address space zero
465 unsigned OpNum) {
466 Value *OldOp = I->getOperand(OpNum);
467 if (OldOp->getType()->getPointerAddressSpace() == 0)
468 return;
469
470 Value *NewOp = aspaceWrapValue(Cache, I->getFunction(), OldOp);
471 I->setOperand(OpNum, NewOp);
472 // Check if there are any remaining users of old GEP,
473 // delete those w/o users
474 for (;;) {
475 auto *OldGEP = dyn_cast<GetElementPtrInst>(OldOp);
476 if (!OldGEP)
477 break;
478 if (!OldGEP->use_empty())
479 break;
480 OldOp = OldGEP->getPointerOperand();
481 OldGEP->eraseFromParent();
482 }
483}
484
485// Support for BPF address spaces:
486// - for each function in the module M, update pointer operand of
487// each memory access instruction (load/store/cmpxchg/atomicrmw)
488// by casting it from non-zero address space to zero address space, e.g:
489//
490// (load (ptr addrspace (N) %p) ...)
491// -> (load (addrspacecast ptr addrspace (N) %p to ptr))
492//
493// - assign section with name .addr_space.N for globals defined in
494// non-zero address space N
495bool BPFCheckAndAdjustIR::insertASpaceCasts(Module &M) {
496 bool Changed = false;
497 for (Function &F : M) {
499 for (BasicBlock &BB : F) {
500 for (Instruction &I : BB) {
501 unsigned PtrOpNum;
502
503 if (auto *LD = dyn_cast<LoadInst>(&I))
504 PtrOpNum = LD->getPointerOperandIndex();
505 else if (auto *ST = dyn_cast<StoreInst>(&I))
506 PtrOpNum = ST->getPointerOperandIndex();
507 else if (auto *CmpXchg = dyn_cast<AtomicCmpXchgInst>(&I))
508 PtrOpNum = CmpXchg->getPointerOperandIndex();
509 else if (auto *RMW = dyn_cast<AtomicRMWInst>(&I))
510 PtrOpNum = RMW->getPointerOperandIndex();
511 else
512 continue;
513
514 aspaceWrapOperand(CastsCache, &I, PtrOpNum);
515 }
516 }
517 Changed |= !CastsCache.empty();
518 }
519 // Merge all globals within same address space into single
520 // .addr_space.<addr space no> section
521 for (GlobalVariable &G : M.globals()) {
522 if (G.getAddressSpace() == 0 || G.hasSection())
523 continue;
524 SmallString<16> SecName;
525 raw_svector_ostream OS(SecName);
526 OS << ".addr_space." << G.getAddressSpace();
527 G.setSection(SecName);
528 // Prevent having separate section for constants
529 G.setConstant(false);
530 }
531 return Changed;
532}
533
534bool BPFCheckAndAdjustIR::adjustIR(Module &M) {
535 bool Changed = removePassThroughBuiltin(M);
536 Changed = removeCompareBuiltin(M) || Changed;
537 Changed = sinkMinMax(M) || Changed;
538 Changed = removeGEPBuiltins(M) || Changed;
539 Changed = insertASpaceCasts(M) || Changed;
540 return Changed;
541}
542
543bool BPFCheckAndAdjustIR::runOnModule(Module &M) {
544 checkIR(M);
545 return adjustIR(M);
546}
SmallVector< AArch64_IMM::ImmInsnModel, 4 > Insn
ReachingDefAnalysis InstSet & ToRemove
static bool sinkMinMaxInBB(BasicBlock &BB, const std::function< bool(Instruction *)> &Filter)
static void aspaceWrapOperand(DenseMap< Value *, Value * > &Cache, Instruction *I, unsigned OpNum)
static void unrollGEPStore(CallInst *Call)
static Value * aspaceWrapValue(DenseMap< Value *, Value * > &Cache, Function *F, Value *ToWrap)
static void unrollGEPLoad(CallInst *Call)
static bool removeGEPBuiltinsInFunc(Function &F)
#define DEBUG_TYPE
static GCRegistry::Add< OcamlGC > B("ocaml", "ocaml 3.10-compatible GC")
static GCRegistry::Add< ErlangGC > A("erlang", "erlang-compatible garbage collector")
Analysis containing CSE Info
Definition: CSEInfo.cpp:27
static GCMetadataPrinterRegistry::Add< ErlangGCPrinter > X("erlang", "erlang-compatible garbage collector")
Hexagon Common GEP
#define F(x, y, z)
Definition: MD5.cpp:55
#define I(x, y, z)
Definition: MD5.cpp:58
#define G(x, y, z)
Definition: MD5.cpp:56
Module.h This file contains the declarations for the Module class.
#define P(N)
#define INITIALIZE_PASS(passName, arg, name, cfg, analysis)
Definition: PassSupport.h:38
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
raw_pwrite_stream & OS
Value * RHS
Value * LHS
Represent the analysis usage information of a pass.
AnalysisUsage & addRequired()
static constexpr StringRef TypeIdAttr
The attribute attached to globals representing a type id.
Definition: BPFCORE.h:48
static constexpr StringRef AmaAttr
The attribute attached to globals representing a field access.
Definition: BPFCORE.h:46
static std::pair< GetElementPtrInst *, StoreInst * > reconstructStore(CallInst *Call)
static std::pair< GetElementPtrInst *, LoadInst * > reconstructLoad(CallInst *Call)
LLVM Basic Block Representation.
Definition: BasicBlock.h:61
This class represents a function call, abstracting a target machine's calling convention.
Predicate
This enumeration lists the possible predicates for CmpInst subclasses.
Definition: InstrTypes.h:757
Predicate getPredicate() const
Return the predicate for this instruction.
Definition: InstrTypes.h:847
iterator find(const_arg_type_t< KeyT > Val)
Definition: DenseMap.h:155
bool empty() const
Definition: DenseMap.h:98
iterator end()
Definition: DenseMap.h:84
This instruction compares its operands according to the predicate given to the constructor.
static bool isGE(Predicate P)
Return true if the predicate is SGE or UGE.
static bool isLT(Predicate P)
Return true if the predicate is SLT or ULT.
static bool isGT(Predicate P)
Return true if the predicate is SGT or UGT.
bool isRelational() const
Return true if the predicate is relational (not EQ or NE).
static bool isLE(Predicate P)
Return true if the predicate is SLE or ULE.
Value * CreateSExt(Value *V, Type *DestTy, const Twine &Name="")
Definition: IRBuilder.h:2053
Value * CreateZExt(Value *V, Type *DestTy, const Twine &Name="", bool IsNonNeg=false)
Definition: IRBuilder.h:2041
Value * CreateLogicalAnd(Value *Cond1, Value *Cond2, const Twine &Name="")
Definition: IRBuilder.h:1693
Value * CreateICmp(CmpInst::Predicate P, Value *LHS, Value *RHS, const Twine &Name="")
Definition: IRBuilder.h:2371
Value * CreateLogicalOr(Value *Cond1, Value *Cond2, const Twine &Name="")
Definition: IRBuilder.h:1699
This provides a uniform API for creating instructions and inserting them into a basic block: either a...
Definition: IRBuilder.h:2686
InstListType::iterator eraseFromParent()
This method unlinks 'this' from the containing basic block and deletes it.
Definition: Instruction.cpp:92
The legacy pass manager's analysis pass to compute loop information.
Definition: LoopInfo.h:593
Represents a single loop in the control flow graph.
Definition: LoopInfo.h:39
ModulePass class - This class is used to implement unstructured interprocedural optimizations and ana...
Definition: Pass.h:251
virtual bool runOnModule(Module &M)=0
runOnModule - Virtual method overriden by subclasses to process the module being operated on.
A Module instance is used to store all the information related to an LLVM module.
Definition: Module.h:65
Value * getIncomingValue(unsigned i) const
Return incoming value number x.
unsigned getNumIncomingValues() const
Return the number of incoming edges.
virtual void getAnalysisUsage(AnalysisUsage &) const
getAnalysisUsage - This function should be overriden by passes that need analysis information to do t...
Definition: Pass.cpp:98
This class represents a sign extension of integer types.
SmallString - A SmallString is just a SmallVector with methods and accessors that make it work better...
Definition: SmallString.h:26
bool empty() const
Definition: SmallVector.h:94
void push_back(const T &Elt)
Definition: SmallVector.h:426
This is a 'vector' (really, a variable-sized array), optimized for the case when the array is small.
Definition: SmallVector.h:1209
unsigned getPointerAddressSpace() const
Get the address space of this pointer or pointer vector type.
Value * getOperand(unsigned i) const
Definition: User.h:169
LLVM Value Representation.
Definition: Value.h:74
Type * getType() const
All values are typed, get the type of this value.
Definition: Value.h:255
void replaceAllUsesWith(Value *V)
Change all uses of this to point to a new Value.
Definition: Value.cpp:534
bool use_empty() const
Definition: Value.h:344
StringRef getName() const
Return a constant reference to the value's name.
Definition: Value.cpp:309
This class represents zero extension of integer types.
A raw_ostream that writes to an SmallVector or SmallString.
Definition: raw_ostream.h:691
unsigned ID
LLVM IR allows to use arbitrary numbers as calling convention identifiers.
Definition: CallingConv.h:24
This is an optimization pass for GlobalISel generic memory operations.
Definition: AddressRanges.h:18
UnaryFunction for_each(R &&Range, UnaryFunction F)
Provide wrappers to std::for_each which take ranges instead of having to pass begin/end explicitly.
Definition: STLExtras.h:1715
ModulePass * createBPFCheckAndAdjustIR()
void report_fatal_error(Error Err, bool gen_crash_diag=true)
Report a serious error, calling any installed error handler.
Definition: Error.cpp:167
@ First
Helpers to iterate all locations in the MemoryEffectsBase class.
ICmpInst::Predicate Predicate
MinMaxSinkInfo(ICmpInst *ICmp, Value *Other, ICmpInst::Predicate Predicate)