Bug Summary

File:llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
Warning:line 279, column 5
Called C++ object pointer is null

Annotated Source Code

Press '?' to see keyboard shortcuts

clang -cc1 -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name AsmPrinter.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 -fhalf-no-semantic-interposition -mframe-pointer=none -fmath-errno -fno-rounding-math -mconstructor-aliases -munwind-tables -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -ffunction-sections -fdata-sections -fcoverage-compilation-dir=/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/build-llvm/lib/CodeGen/AsmPrinter -resource-dir /usr/lib/llvm-13/lib/clang/13.0.0 -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I /build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/build-llvm/lib/CodeGen/AsmPrinter -I /build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter -I /build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/build-llvm/include -I /build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/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/c++/6.3.0/backward -internal-isystem /usr/local/include -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../x86_64-linux-gnu/include -internal-isystem /usr/lib/llvm-13/lib/clang/13.0.0/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-13~++20210405022414+5f57793c4fe4/build-llvm/lib/CodeGen/AsmPrinter -fdebug-prefix-map=/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4=. -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 -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /tmp/scan-build-2021-04-05-202135-9119-1 -x c++ /build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
1//===- AsmPrinter.cpp - Common AsmPrinter code ----------------------------===//
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 implements the AsmPrinter class.
10//
11//===----------------------------------------------------------------------===//
12
13#include "llvm/CodeGen/AsmPrinter.h"
14#include "CodeViewDebug.h"
15#include "DwarfDebug.h"
16#include "DwarfException.h"
17#include "PseudoProbePrinter.h"
18#include "WasmException.h"
19#include "WinCFGuard.h"
20#include "WinException.h"
21#include "llvm/ADT/APFloat.h"
22#include "llvm/ADT/APInt.h"
23#include "llvm/ADT/DenseMap.h"
24#include "llvm/ADT/STLExtras.h"
25#include "llvm/ADT/SmallPtrSet.h"
26#include "llvm/ADT/SmallString.h"
27#include "llvm/ADT/SmallVector.h"
28#include "llvm/ADT/Statistic.h"
29#include "llvm/ADT/StringRef.h"
30#include "llvm/ADT/Triple.h"
31#include "llvm/ADT/Twine.h"
32#include "llvm/Analysis/ConstantFolding.h"
33#include "llvm/Analysis/EHPersonalities.h"
34#include "llvm/Analysis/MemoryLocation.h"
35#include "llvm/Analysis/OptimizationRemarkEmitter.h"
36#include "llvm/BinaryFormat/COFF.h"
37#include "llvm/BinaryFormat/Dwarf.h"
38#include "llvm/BinaryFormat/ELF.h"
39#include "llvm/CodeGen/GCMetadata.h"
40#include "llvm/CodeGen/GCMetadataPrinter.h"
41#include "llvm/CodeGen/GCStrategy.h"
42#include "llvm/CodeGen/MachineBasicBlock.h"
43#include "llvm/CodeGen/MachineConstantPool.h"
44#include "llvm/CodeGen/MachineDominators.h"
45#include "llvm/CodeGen/MachineFrameInfo.h"
46#include "llvm/CodeGen/MachineFunction.h"
47#include "llvm/CodeGen/MachineFunctionPass.h"
48#include "llvm/CodeGen/MachineInstr.h"
49#include "llvm/CodeGen/MachineInstrBundle.h"
50#include "llvm/CodeGen/MachineJumpTableInfo.h"
51#include "llvm/CodeGen/MachineLoopInfo.h"
52#include "llvm/CodeGen/MachineMemOperand.h"
53#include "llvm/CodeGen/MachineModuleInfo.h"
54#include "llvm/CodeGen/MachineModuleInfoImpls.h"
55#include "llvm/CodeGen/MachineOperand.h"
56#include "llvm/CodeGen/MachineOptimizationRemarkEmitter.h"
57#include "llvm/CodeGen/StackMaps.h"
58#include "llvm/CodeGen/TargetFrameLowering.h"
59#include "llvm/CodeGen/TargetInstrInfo.h"
60#include "llvm/CodeGen/TargetLowering.h"
61#include "llvm/CodeGen/TargetOpcodes.h"
62#include "llvm/CodeGen/TargetRegisterInfo.h"
63#include "llvm/IR/BasicBlock.h"
64#include "llvm/IR/Comdat.h"
65#include "llvm/IR/Constant.h"
66#include "llvm/IR/Constants.h"
67#include "llvm/IR/DataLayout.h"
68#include "llvm/IR/DebugInfoMetadata.h"
69#include "llvm/IR/DerivedTypes.h"
70#include "llvm/IR/Function.h"
71#include "llvm/IR/GlobalAlias.h"
72#include "llvm/IR/GlobalIFunc.h"
73#include "llvm/IR/GlobalIndirectSymbol.h"
74#include "llvm/IR/GlobalObject.h"
75#include "llvm/IR/GlobalValue.h"
76#include "llvm/IR/GlobalVariable.h"
77#include "llvm/IR/Instruction.h"
78#include "llvm/IR/Mangler.h"
79#include "llvm/IR/Metadata.h"
80#include "llvm/IR/Module.h"
81#include "llvm/IR/Operator.h"
82#include "llvm/IR/PseudoProbe.h"
83#include "llvm/IR/Type.h"
84#include "llvm/IR/Value.h"
85#include "llvm/MC/MCAsmInfo.h"
86#include "llvm/MC/MCContext.h"
87#include "llvm/MC/MCDirectives.h"
88#include "llvm/MC/MCDwarf.h"
89#include "llvm/MC/MCExpr.h"
90#include "llvm/MC/MCInst.h"
91#include "llvm/MC/MCSection.h"
92#include "llvm/MC/MCSectionCOFF.h"
93#include "llvm/MC/MCSectionELF.h"
94#include "llvm/MC/MCSectionMachO.h"
95#include "llvm/MC/MCSectionXCOFF.h"
96#include "llvm/MC/MCStreamer.h"
97#include "llvm/MC/MCSubtargetInfo.h"
98#include "llvm/MC/MCSymbol.h"
99#include "llvm/MC/MCSymbolELF.h"
100#include "llvm/MC/MCSymbolXCOFF.h"
101#include "llvm/MC/MCTargetOptions.h"
102#include "llvm/MC/MCValue.h"
103#include "llvm/MC/SectionKind.h"
104#include "llvm/Pass.h"
105#include "llvm/Remarks/Remark.h"
106#include "llvm/Remarks/RemarkFormat.h"
107#include "llvm/Remarks/RemarkStreamer.h"
108#include "llvm/Remarks/RemarkStringTable.h"
109#include "llvm/Support/Casting.h"
110#include "llvm/Support/CommandLine.h"
111#include "llvm/Support/Compiler.h"
112#include "llvm/Support/ErrorHandling.h"
113#include "llvm/Support/Format.h"
114#include "llvm/Support/MathExtras.h"
115#include "llvm/Support/Path.h"
116#include "llvm/Support/TargetRegistry.h"
117#include "llvm/Support/Timer.h"
118#include "llvm/Support/raw_ostream.h"
119#include "llvm/Target/TargetLoweringObjectFile.h"
120#include "llvm/Target/TargetMachine.h"
121#include "llvm/Target/TargetOptions.h"
122#include <algorithm>
123#include <cassert>
124#include <cinttypes>
125#include <cstdint>
126#include <iterator>
127#include <limits>
128#include <memory>
129#include <string>
130#include <utility>
131#include <vector>
132
133using namespace llvm;
134
135#define DEBUG_TYPE"asm-printer" "asm-printer"
136
137// FIXME: this option currently only applies to DWARF, and not CodeView, tables
138static cl::opt<bool>
139 DisableDebugInfoPrinting("disable-debug-info-print", cl::Hidden,
140 cl::desc("Disable debug info printing"));
141
142const char DWARFGroupName[] = "dwarf";
143const char DWARFGroupDescription[] = "DWARF Emission";
144const char DbgTimerName[] = "emit";
145const char DbgTimerDescription[] = "Debug Info Emission";
146const char EHTimerName[] = "write_exception";
147const char EHTimerDescription[] = "DWARF Exception Writer";
148const char CFGuardName[] = "Control Flow Guard";
149const char CFGuardDescription[] = "Control Flow Guard";
150const char CodeViewLineTablesGroupName[] = "linetables";
151const char CodeViewLineTablesGroupDescription[] = "CodeView Line Tables";
152const char PPTimerName[] = "emit";
153const char PPTimerDescription[] = "Pseudo Probe Emission";
154const char PPGroupName[] = "pseudo probe";
155const char PPGroupDescription[] = "Pseudo Probe Emission";
156
157STATISTIC(EmittedInsts, "Number of machine instrs printed")static llvm::Statistic EmittedInsts = {"asm-printer", "EmittedInsts"
, "Number of machine instrs printed"}
;
158
159char AsmPrinter::ID = 0;
160
161using gcp_map_type = DenseMap<GCStrategy *, std::unique_ptr<GCMetadataPrinter>>;
162
163static gcp_map_type &getGCMap(void *&P) {
164 if (!P)
165 P = new gcp_map_type();
166 return *(gcp_map_type*)P;
167}
168
169/// getGVAlignment - Return the alignment to use for the specified global
170/// value. This rounds up to the preferred alignment if possible and legal.
171Align AsmPrinter::getGVAlignment(const GlobalObject *GV, const DataLayout &DL,
172 Align InAlign) {
173 Align Alignment;
174 if (const GlobalVariable *GVar = dyn_cast<GlobalVariable>(GV))
175 Alignment = DL.getPreferredAlign(GVar);
176
177 // If InAlign is specified, round it to it.
178 if (InAlign > Alignment)
179 Alignment = InAlign;
180
181 // If the GV has a specified alignment, take it into account.
182 const MaybeAlign GVAlign(GV->getAlignment());
183 if (!GVAlign)
184 return Alignment;
185
186 assert(GVAlign && "GVAlign must be set")((GVAlign && "GVAlign must be set") ? static_cast<
void> (0) : __assert_fail ("GVAlign && \"GVAlign must be set\""
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 186, __PRETTY_FUNCTION__))
;
187
188 // If the GVAlign is larger than NumBits, or if we are required to obey
189 // NumBits because the GV has an assigned section, obey it.
190 if (*GVAlign > Alignment || GV->hasSection())
191 Alignment = *GVAlign;
192 return Alignment;
193}
194
195AsmPrinter::AsmPrinter(TargetMachine &tm, std::unique_ptr<MCStreamer> Streamer)
196 : MachineFunctionPass(ID), TM(tm), MAI(tm.getMCAsmInfo()),
197 OutContext(Streamer->getContext()), OutStreamer(std::move(Streamer)) {
198 VerboseAsm = OutStreamer->isVerboseAsm();
199}
200
201AsmPrinter::~AsmPrinter() {
202 assert(!DD && Handlers.size() == NumUserHandlers &&((!DD && Handlers.size() == NumUserHandlers &&
"Debug/EH info didn't get finalized") ? static_cast<void>
(0) : __assert_fail ("!DD && Handlers.size() == NumUserHandlers && \"Debug/EH info didn't get finalized\""
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 203, __PRETTY_FUNCTION__))
203 "Debug/EH info didn't get finalized")((!DD && Handlers.size() == NumUserHandlers &&
"Debug/EH info didn't get finalized") ? static_cast<void>
(0) : __assert_fail ("!DD && Handlers.size() == NumUserHandlers && \"Debug/EH info didn't get finalized\""
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 203, __PRETTY_FUNCTION__))
;
204
205 if (GCMetadataPrinters) {
206 gcp_map_type &GCMap = getGCMap(GCMetadataPrinters);
207
208 delete &GCMap;
209 GCMetadataPrinters = nullptr;
210 }
211}
212
213bool AsmPrinter::isPositionIndependent() const {
214 return TM.isPositionIndependent();
215}
216
217/// getFunctionNumber - Return a unique ID for the current function.
218unsigned AsmPrinter::getFunctionNumber() const {
219 return MF->getFunctionNumber();
220}
221
222const TargetLoweringObjectFile &AsmPrinter::getObjFileLowering() const {
223 return *TM.getObjFileLowering();
224}
225
226const DataLayout &AsmPrinter::getDataLayout() const {
227 return MMI->getModule()->getDataLayout();
228}
229
230// Do not use the cached DataLayout because some client use it without a Module
231// (dsymutil, llvm-dwarfdump).
232unsigned AsmPrinter::getPointerSize() const {
233 return TM.getPointerSize(0); // FIXME: Default address space
234}
235
236const MCSubtargetInfo &AsmPrinter::getSubtargetInfo() const {
237 assert(MF && "getSubtargetInfo requires a valid MachineFunction!")((MF && "getSubtargetInfo requires a valid MachineFunction!"
) ? static_cast<void> (0) : __assert_fail ("MF && \"getSubtargetInfo requires a valid MachineFunction!\""
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 237, __PRETTY_FUNCTION__))
;
238 return MF->getSubtarget<MCSubtargetInfo>();
239}
240
241void AsmPrinter::EmitToStreamer(MCStreamer &S, const MCInst &Inst) {
242 S.emitInstruction(Inst, getSubtargetInfo());
243}
244
245void AsmPrinter::emitInitialRawDwarfLocDirective(const MachineFunction &MF) {
246 if (DD) {
247 assert(OutStreamer->hasRawTextSupport() &&((OutStreamer->hasRawTextSupport() && "Expected assembly output mode."
) ? static_cast<void> (0) : __assert_fail ("OutStreamer->hasRawTextSupport() && \"Expected assembly output mode.\""
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 248, __PRETTY_FUNCTION__))
248 "Expected assembly output mode.")((OutStreamer->hasRawTextSupport() && "Expected assembly output mode."
) ? static_cast<void> (0) : __assert_fail ("OutStreamer->hasRawTextSupport() && \"Expected assembly output mode.\""
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 248, __PRETTY_FUNCTION__))
;
249 (void)DD->emitInitialLocDirective(MF, /*CUID=*/0);
250 }
251}
252
253/// getCurrentSection() - Return the current section we are emitting to.
254const MCSection *AsmPrinter::getCurrentSection() const {
255 return OutStreamer->getCurrentSectionOnly();
256}
257
258void AsmPrinter::getAnalysisUsage(AnalysisUsage &AU) const {
259 AU.setPreservesAll();
260 MachineFunctionPass::getAnalysisUsage(AU);
261 AU.addRequired<MachineOptimizationRemarkEmitterPass>();
262 AU.addRequired<GCModuleInfo>();
263}
264
265bool AsmPrinter::doInitialization(Module &M) {
266 auto *MMIWP = getAnalysisIfAvailable<MachineModuleInfoWrapperPass>();
267 MMI = MMIWP
0.1
'MMIWP' is null
? &MMIWP->getMMI() : nullptr
;
1
'?' condition is false
2
Null pointer value stored to field 'MMI'
268
269 // Initialize TargetLoweringObjectFile.
270 const_cast<TargetLoweringObjectFile&>(getObjFileLowering())
271 .Initialize(OutContext, TM);
272
273 const_cast<TargetLoweringObjectFile &>(getObjFileLowering())
274 .getModuleMetadata(M);
275
276 OutStreamer->InitSections(false);
277
278 if (DisableDebugInfoPrinting)
3
Assuming the condition is true
4
Taking true branch
279 MMI->setDebugInfoAvailability(false);
5
Called C++ object pointer is null
280
281 // Emit the version-min deployment target directive if needed.
282 //
283 // FIXME: If we end up with a collection of these sorts of Darwin-specific
284 // or ELF-specific things, it may make sense to have a platform helper class
285 // that will work with the target helper class. For now keep it here, as the
286 // alternative is duplicated code in each of the target asm printers that
287 // use the directive, where it would need the same conditionalization
288 // anyway.
289 const Triple &Target = TM.getTargetTriple();
290 OutStreamer->emitVersionForTarget(Target, M.getSDKVersion());
291
292 // Allow the target to emit any magic that it wants at the start of the file.
293 emitStartOfAsmFile(M);
294
295 // Very minimal debug info. It is ignored if we emit actual debug info. If we
296 // don't, this at least helps the user find where a global came from.
297 if (MAI->hasSingleParameterDotFile()) {
298 // .file "foo.c"
299 OutStreamer->emitFileDirective(
300 llvm::sys::path::filename(M.getSourceFileName()));
301 }
302
303 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
304 assert(MI && "AsmPrinter didn't require GCModuleInfo?")((MI && "AsmPrinter didn't require GCModuleInfo?") ? static_cast
<void> (0) : __assert_fail ("MI && \"AsmPrinter didn't require GCModuleInfo?\""
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 304, __PRETTY_FUNCTION__))
;
305 for (auto &I : *MI)
306 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*I))
307 MP->beginAssembly(M, *MI, *this);
308
309 // Emit module-level inline asm if it exists.
310 if (!M.getModuleInlineAsm().empty()) {
311 // We're at the module level. Construct MCSubtarget from the default CPU
312 // and target triple.
313 std::unique_ptr<MCSubtargetInfo> STI(TM.getTarget().createMCSubtargetInfo(
314 TM.getTargetTriple().str(), TM.getTargetCPU(),
315 TM.getTargetFeatureString()));
316 assert(STI && "Unable to create subtarget info")((STI && "Unable to create subtarget info") ? static_cast
<void> (0) : __assert_fail ("STI && \"Unable to create subtarget info\""
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 316, __PRETTY_FUNCTION__))
;
317 OutStreamer->AddComment("Start of file scope inline assembly");
318 OutStreamer->AddBlankLine();
319 emitInlineAsm(M.getModuleInlineAsm() + "\n",
320 OutContext.getSubtargetCopy(*STI), TM.Options.MCOptions);
321 OutStreamer->AddComment("End of file scope inline assembly");
322 OutStreamer->AddBlankLine();
323 }
324
325 if (MAI->doesSupportDebugInformation()) {
326 bool EmitCodeView = M.getCodeViewFlag();
327 if (EmitCodeView && TM.getTargetTriple().isOSWindows()) {
328 Handlers.emplace_back(std::make_unique<CodeViewDebug>(this),
329 DbgTimerName, DbgTimerDescription,
330 CodeViewLineTablesGroupName,
331 CodeViewLineTablesGroupDescription);
332 }
333 if (!EmitCodeView || M.getDwarfVersion()) {
334 if (!DisableDebugInfoPrinting) {
335 DD = new DwarfDebug(this);
336 Handlers.emplace_back(std::unique_ptr<DwarfDebug>(DD), DbgTimerName,
337 DbgTimerDescription, DWARFGroupName,
338 DWARFGroupDescription);
339 }
340 }
341 }
342
343 if (M.getNamedMetadata(PseudoProbeDescMetadataName)) {
344 PP = new PseudoProbeHandler(this, &M);
345 Handlers.emplace_back(std::unique_ptr<PseudoProbeHandler>(PP), PPTimerName,
346 PPTimerDescription, PPGroupName, PPGroupDescription);
347 }
348
349 switch (MAI->getExceptionHandlingType()) {
350 case ExceptionHandling::SjLj:
351 case ExceptionHandling::DwarfCFI:
352 case ExceptionHandling::ARM:
353 isCFIMoveForDebugging = true;
354 if (MAI->getExceptionHandlingType() != ExceptionHandling::DwarfCFI)
355 break;
356 for (auto &F: M.getFunctionList()) {
357 // If the module contains any function with unwind data,
358 // .eh_frame has to be emitted.
359 // Ignore functions that won't get emitted.
360 if (!F.isDeclarationForLinker() && F.needsUnwindTableEntry()) {
361 isCFIMoveForDebugging = false;
362 break;
363 }
364 }
365 break;
366 default:
367 isCFIMoveForDebugging = false;
368 break;
369 }
370
371 EHStreamer *ES = nullptr;
372 switch (MAI->getExceptionHandlingType()) {
373 case ExceptionHandling::None:
374 break;
375 case ExceptionHandling::SjLj:
376 case ExceptionHandling::DwarfCFI:
377 ES = new DwarfCFIException(this);
378 break;
379 case ExceptionHandling::ARM:
380 ES = new ARMException(this);
381 break;
382 case ExceptionHandling::WinEH:
383 switch (MAI->getWinEHEncodingType()) {
384 default: llvm_unreachable("unsupported unwinding information encoding")::llvm::llvm_unreachable_internal("unsupported unwinding information encoding"
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 384)
;
385 case WinEH::EncodingType::Invalid:
386 break;
387 case WinEH::EncodingType::X86:
388 case WinEH::EncodingType::Itanium:
389 ES = new WinException(this);
390 break;
391 }
392 break;
393 case ExceptionHandling::Wasm:
394 ES = new WasmException(this);
395 break;
396 case ExceptionHandling::AIX:
397 ES = new AIXException(this);
398 break;
399 }
400 if (ES)
401 Handlers.emplace_back(std::unique_ptr<EHStreamer>(ES), EHTimerName,
402 EHTimerDescription, DWARFGroupName,
403 DWARFGroupDescription);
404
405 // Emit tables for any value of cfguard flag (i.e. cfguard=1 or cfguard=2).
406 if (mdconst::extract_or_null<ConstantInt>(M.getModuleFlag("cfguard")))
407 Handlers.emplace_back(std::make_unique<WinCFGuard>(this), CFGuardName,
408 CFGuardDescription, DWARFGroupName,
409 DWARFGroupDescription);
410
411 for (const HandlerInfo &HI : Handlers) {
412 NamedRegionTimer T(HI.TimerName, HI.TimerDescription, HI.TimerGroupName,
413 HI.TimerGroupDescription, TimePassesIsEnabled);
414 HI.Handler->beginModule(&M);
415 }
416
417 return false;
418}
419
420static bool canBeHidden(const GlobalValue *GV, const MCAsmInfo &MAI) {
421 if (!MAI.hasWeakDefCanBeHiddenDirective())
422 return false;
423
424 return GV->canBeOmittedFromSymbolTable();
425}
426
427void AsmPrinter::emitLinkage(const GlobalValue *GV, MCSymbol *GVSym) const {
428 GlobalValue::LinkageTypes Linkage = GV->getLinkage();
429 switch (Linkage) {
430 case GlobalValue::CommonLinkage:
431 case GlobalValue::LinkOnceAnyLinkage:
432 case GlobalValue::LinkOnceODRLinkage:
433 case GlobalValue::WeakAnyLinkage:
434 case GlobalValue::WeakODRLinkage:
435 if (MAI->hasWeakDefDirective()) {
436 // .globl _foo
437 OutStreamer->emitSymbolAttribute(GVSym, MCSA_Global);
438
439 if (!canBeHidden(GV, *MAI))
440 // .weak_definition _foo
441 OutStreamer->emitSymbolAttribute(GVSym, MCSA_WeakDefinition);
442 else
443 OutStreamer->emitSymbolAttribute(GVSym, MCSA_WeakDefAutoPrivate);
444 } else if (MAI->avoidWeakIfComdat() && GV->hasComdat()) {
445 // .globl _foo
446 OutStreamer->emitSymbolAttribute(GVSym, MCSA_Global);
447 //NOTE: linkonce is handled by the section the symbol was assigned to.
448 } else {
449 // .weak _foo
450 OutStreamer->emitSymbolAttribute(GVSym, MCSA_Weak);
451 }
452 return;
453 case GlobalValue::ExternalLinkage:
454 OutStreamer->emitSymbolAttribute(GVSym, MCSA_Global);
455 return;
456 case GlobalValue::PrivateLinkage:
457 case GlobalValue::InternalLinkage:
458 return;
459 case GlobalValue::ExternalWeakLinkage:
460 case GlobalValue::AvailableExternallyLinkage:
461 case GlobalValue::AppendingLinkage:
462 llvm_unreachable("Should never emit this")::llvm::llvm_unreachable_internal("Should never emit this", "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 462)
;
463 }
464 llvm_unreachable("Unknown linkage type!")::llvm::llvm_unreachable_internal("Unknown linkage type!", "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 464)
;
465}
466
467void AsmPrinter::getNameWithPrefix(SmallVectorImpl<char> &Name,
468 const GlobalValue *GV) const {
469 TM.getNameWithPrefix(Name, GV, getObjFileLowering().getMangler());
470}
471
472MCSymbol *AsmPrinter::getSymbol(const GlobalValue *GV) const {
473 return TM.getSymbol(GV);
474}
475
476MCSymbol *AsmPrinter::getSymbolPreferLocal(const GlobalValue &GV) const {
477 // On ELF, use .Lfoo$local if GV is a non-interposable GlobalObject with an
478 // exact definion (intersection of GlobalValue::hasExactDefinition() and
479 // !isInterposable()). These linkages include: external, appending, internal,
480 // private. It may be profitable to use a local alias for external. The
481 // assembler would otherwise be conservative and assume a global default
482 // visibility symbol can be interposable, even if the code generator already
483 // assumed it.
484 if (TM.getTargetTriple().isOSBinFormatELF() && GV.canBenefitFromLocalAlias()) {
485 const Module &M = *GV.getParent();
486 if (TM.getRelocationModel() != Reloc::Static &&
487 M.getPIELevel() == PIELevel::Default && GV.isDSOLocal())
488 return getSymbolWithGlobalValueBase(&GV, "$local");
489 }
490 return TM.getSymbol(&GV);
491}
492
493/// EmitGlobalVariable - Emit the specified global variable to the .s file.
494void AsmPrinter::emitGlobalVariable(const GlobalVariable *GV) {
495 bool IsEmuTLSVar = TM.useEmulatedTLS() && GV->isThreadLocal();
496 assert(!(IsEmuTLSVar && GV->hasCommonLinkage()) &&((!(IsEmuTLSVar && GV->hasCommonLinkage()) &&
"No emulated TLS variables in the common section") ? static_cast
<void> (0) : __assert_fail ("!(IsEmuTLSVar && GV->hasCommonLinkage()) && \"No emulated TLS variables in the common section\""
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 497, __PRETTY_FUNCTION__))
497 "No emulated TLS variables in the common section")((!(IsEmuTLSVar && GV->hasCommonLinkage()) &&
"No emulated TLS variables in the common section") ? static_cast
<void> (0) : __assert_fail ("!(IsEmuTLSVar && GV->hasCommonLinkage()) && \"No emulated TLS variables in the common section\""
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 497, __PRETTY_FUNCTION__))
;
498
499 // Never emit TLS variable xyz in emulated TLS model.
500 // The initialization value is in __emutls_t.xyz instead of xyz.
501 if (IsEmuTLSVar)
502 return;
503
504 if (GV->hasInitializer()) {
505 // Check to see if this is a special global used by LLVM, if so, emit it.
506 if (emitSpecialLLVMGlobal(GV))
507 return;
508
509 // Skip the emission of global equivalents. The symbol can be emitted later
510 // on by emitGlobalGOTEquivs in case it turns out to be needed.
511 if (GlobalGOTEquivs.count(getSymbol(GV)))
512 return;
513
514 if (isVerbose()) {
515 // When printing the control variable __emutls_v.*,
516 // we don't need to print the original TLS variable name.
517 GV->printAsOperand(OutStreamer->GetCommentOS(),
518 /*PrintType=*/false, GV->getParent());
519 OutStreamer->GetCommentOS() << '\n';
520 }
521 }
522
523 MCSymbol *GVSym = getSymbol(GV);
524 MCSymbol *EmittedSym = GVSym;
525
526 // getOrCreateEmuTLSControlSym only creates the symbol with name and default
527 // attributes.
528 // GV's or GVSym's attributes will be used for the EmittedSym.
529 emitVisibility(EmittedSym, GV->getVisibility(), !GV->isDeclaration());
530
531 if (!GV->hasInitializer()) // External globals require no extra code.
532 return;
533
534 GVSym->redefineIfPossible();
535 if (GVSym->isDefined() || GVSym->isVariable())
536 OutContext.reportError(SMLoc(), "symbol '" + Twine(GVSym->getName()) +
537 "' is already defined");
538
539 if (MAI->hasDotTypeDotSizeDirective())
540 OutStreamer->emitSymbolAttribute(EmittedSym, MCSA_ELF_TypeObject);
541
542 SectionKind GVKind = TargetLoweringObjectFile::getKindForGlobal(GV, TM);
543
544 const DataLayout &DL = GV->getParent()->getDataLayout();
545 uint64_t Size = DL.getTypeAllocSize(GV->getValueType());
546
547 // If the alignment is specified, we *must* obey it. Overaligning a global
548 // with a specified alignment is a prompt way to break globals emitted to
549 // sections and expected to be contiguous (e.g. ObjC metadata).
550 const Align Alignment = getGVAlignment(GV, DL);
551
552 for (const HandlerInfo &HI : Handlers) {
553 NamedRegionTimer T(HI.TimerName, HI.TimerDescription,
554 HI.TimerGroupName, HI.TimerGroupDescription,
555 TimePassesIsEnabled);
556 HI.Handler->setSymbolSize(GVSym, Size);
557 }
558
559 // Handle common symbols
560 if (GVKind.isCommon()) {
561 if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
562 // .comm _foo, 42, 4
563 const bool SupportsAlignment =
564 getObjFileLowering().getCommDirectiveSupportsAlignment();
565 OutStreamer->emitCommonSymbol(GVSym, Size,
566 SupportsAlignment ? Alignment.value() : 0);
567 return;
568 }
569
570 // Determine to which section this global should be emitted.
571 MCSection *TheSection = getObjFileLowering().SectionForGlobal(GV, GVKind, TM);
572
573 // If we have a bss global going to a section that supports the
574 // zerofill directive, do so here.
575 if (GVKind.isBSS() && MAI->hasMachoZeroFillDirective() &&
576 TheSection->isVirtualSection()) {
577 if (Size == 0)
578 Size = 1; // zerofill of 0 bytes is undefined.
579 emitLinkage(GV, GVSym);
580 // .zerofill __DATA, __bss, _foo, 400, 5
581 OutStreamer->emitZerofill(TheSection, GVSym, Size, Alignment.value());
582 return;
583 }
584
585 // If this is a BSS local symbol and we are emitting in the BSS
586 // section use .lcomm/.comm directive.
587 if (GVKind.isBSSLocal() &&
588 getObjFileLowering().getBSSSection() == TheSection) {
589 if (Size == 0)
590 Size = 1; // .comm Foo, 0 is undefined, avoid it.
591
592 // Use .lcomm only if it supports user-specified alignment.
593 // Otherwise, while it would still be correct to use .lcomm in some
594 // cases (e.g. when Align == 1), the external assembler might enfore
595 // some -unknown- default alignment behavior, which could cause
596 // spurious differences between external and integrated assembler.
597 // Prefer to simply fall back to .local / .comm in this case.
598 if (MAI->getLCOMMDirectiveAlignmentType() != LCOMM::NoAlignment) {
599 // .lcomm _foo, 42
600 OutStreamer->emitLocalCommonSymbol(GVSym, Size, Alignment.value());
601 return;
602 }
603
604 // .local _foo
605 OutStreamer->emitSymbolAttribute(GVSym, MCSA_Local);
606 // .comm _foo, 42, 4
607 const bool SupportsAlignment =
608 getObjFileLowering().getCommDirectiveSupportsAlignment();
609 OutStreamer->emitCommonSymbol(GVSym, Size,
610 SupportsAlignment ? Alignment.value() : 0);
611 return;
612 }
613
614 // Handle thread local data for mach-o which requires us to output an
615 // additional structure of data and mangle the original symbol so that we
616 // can reference it later.
617 //
618 // TODO: This should become an "emit thread local global" method on TLOF.
619 // All of this macho specific stuff should be sunk down into TLOFMachO and
620 // stuff like "TLSExtraDataSection" should no longer be part of the parent
621 // TLOF class. This will also make it more obvious that stuff like
622 // MCStreamer::EmitTBSSSymbol is macho specific and only called from macho
623 // specific code.
624 if (GVKind.isThreadLocal() && MAI->hasMachoTBSSDirective()) {
625 // Emit the .tbss symbol
626 MCSymbol *MangSym =
627 OutContext.getOrCreateSymbol(GVSym->getName() + Twine("$tlv$init"));
628
629 if (GVKind.isThreadBSS()) {
630 TheSection = getObjFileLowering().getTLSBSSSection();
631 OutStreamer->emitTBSSSymbol(TheSection, MangSym, Size, Alignment.value());
632 } else if (GVKind.isThreadData()) {
633 OutStreamer->SwitchSection(TheSection);
634
635 emitAlignment(Alignment, GV);
636 OutStreamer->emitLabel(MangSym);
637
638 emitGlobalConstant(GV->getParent()->getDataLayout(),
639 GV->getInitializer());
640 }
641
642 OutStreamer->AddBlankLine();
643
644 // Emit the variable struct for the runtime.
645 MCSection *TLVSect = getObjFileLowering().getTLSExtraDataSection();
646
647 OutStreamer->SwitchSection(TLVSect);
648 // Emit the linkage here.
649 emitLinkage(GV, GVSym);
650 OutStreamer->emitLabel(GVSym);
651
652 // Three pointers in size:
653 // - __tlv_bootstrap - used to make sure support exists
654 // - spare pointer, used when mapped by the runtime
655 // - pointer to mangled symbol above with initializer
656 unsigned PtrSize = DL.getPointerTypeSize(GV->getType());
657 OutStreamer->emitSymbolValue(GetExternalSymbolSymbol("_tlv_bootstrap"),
658 PtrSize);
659 OutStreamer->emitIntValue(0, PtrSize);
660 OutStreamer->emitSymbolValue(MangSym, PtrSize);
661
662 OutStreamer->AddBlankLine();
663 return;
664 }
665
666 MCSymbol *EmittedInitSym = GVSym;
667
668 OutStreamer->SwitchSection(TheSection);
669
670 emitLinkage(GV, EmittedInitSym);
671 emitAlignment(Alignment, GV);
672
673 OutStreamer->emitLabel(EmittedInitSym);
674 MCSymbol *LocalAlias = getSymbolPreferLocal(*GV);
675 if (LocalAlias != EmittedInitSym)
676 OutStreamer->emitLabel(LocalAlias);
677
678 emitGlobalConstant(GV->getParent()->getDataLayout(), GV->getInitializer());
679
680 if (MAI->hasDotTypeDotSizeDirective())
681 // .size foo, 42
682 OutStreamer->emitELFSize(EmittedInitSym,
683 MCConstantExpr::create(Size, OutContext));
684
685 OutStreamer->AddBlankLine();
686}
687
688/// Emit the directive and value for debug thread local expression
689///
690/// \p Value - The value to emit.
691/// \p Size - The size of the integer (in bytes) to emit.
692void AsmPrinter::emitDebugValue(const MCExpr *Value, unsigned Size) const {
693 OutStreamer->emitValue(Value, Size);
694}
695
696void AsmPrinter::emitFunctionHeaderComment() {}
697
698/// EmitFunctionHeader - This method emits the header for the current
699/// function.
700void AsmPrinter::emitFunctionHeader() {
701 const Function &F = MF->getFunction();
702
703 if (isVerbose())
704 OutStreamer->GetCommentOS()
705 << "-- Begin function "
706 << GlobalValue::dropLLVMManglingEscape(F.getName()) << '\n';
707
708 // Print out constants referenced by the function
709 emitConstantPool();
710
711 // Print the 'header' of function.
712 // If basic block sections is desired and function sections is off,
713 // explicitly request a unique section for this function.
714 if (MF->front().isBeginSection() && !TM.getFunctionSections())
715 MF->setSection(getObjFileLowering().getUniqueSectionForFunction(F, TM));
716 else
717 MF->setSection(getObjFileLowering().SectionForGlobal(&F, TM));
718 OutStreamer->SwitchSection(MF->getSection());
719
720 if (!MAI->hasVisibilityOnlyWithLinkage())
721 emitVisibility(CurrentFnSym, F.getVisibility());
722
723 if (MAI->needsFunctionDescriptors())
724 emitLinkage(&F, CurrentFnDescSym);
725
726 emitLinkage(&F, CurrentFnSym);
727 if (MAI->hasFunctionAlignment())
728 emitAlignment(MF->getAlignment(), &F);
729
730 if (MAI->hasDotTypeDotSizeDirective())
731 OutStreamer->emitSymbolAttribute(CurrentFnSym, MCSA_ELF_TypeFunction);
732
733 if (F.hasFnAttribute(Attribute::Cold))
734 OutStreamer->emitSymbolAttribute(CurrentFnSym, MCSA_Cold);
735
736 if (isVerbose()) {
737 F.printAsOperand(OutStreamer->GetCommentOS(),
738 /*PrintType=*/false, F.getParent());
739 emitFunctionHeaderComment();
740 OutStreamer->GetCommentOS() << '\n';
741 }
742
743 // Emit the prefix data.
744 if (F.hasPrefixData()) {
745 if (MAI->hasSubsectionsViaSymbols()) {
746 // Preserving prefix data on platforms which use subsections-via-symbols
747 // is a bit tricky. Here we introduce a symbol for the prefix data
748 // and use the .alt_entry attribute to mark the function's real entry point
749 // as an alternative entry point to the prefix-data symbol.
750 MCSymbol *PrefixSym = OutContext.createLinkerPrivateTempSymbol();
751 OutStreamer->emitLabel(PrefixSym);
752
753 emitGlobalConstant(F.getParent()->getDataLayout(), F.getPrefixData());
754
755 // Emit an .alt_entry directive for the actual function symbol.
756 OutStreamer->emitSymbolAttribute(CurrentFnSym, MCSA_AltEntry);
757 } else {
758 emitGlobalConstant(F.getParent()->getDataLayout(), F.getPrefixData());
759 }
760 }
761
762 // Emit M NOPs for -fpatchable-function-entry=N,M where M>0. We arbitrarily
763 // place prefix data before NOPs.
764 unsigned PatchableFunctionPrefix = 0;
765 unsigned PatchableFunctionEntry = 0;
766 (void)F.getFnAttribute("patchable-function-prefix")
767 .getValueAsString()
768 .getAsInteger(10, PatchableFunctionPrefix);
769 (void)F.getFnAttribute("patchable-function-entry")
770 .getValueAsString()
771 .getAsInteger(10, PatchableFunctionEntry);
772 if (PatchableFunctionPrefix) {
773 CurrentPatchableFunctionEntrySym =
774 OutContext.createLinkerPrivateTempSymbol();
775 OutStreamer->emitLabel(CurrentPatchableFunctionEntrySym);
776 emitNops(PatchableFunctionPrefix);
777 } else if (PatchableFunctionEntry) {
778 // May be reassigned when emitting the body, to reference the label after
779 // the initial BTI (AArch64) or endbr32/endbr64 (x86).
780 CurrentPatchableFunctionEntrySym = CurrentFnBegin;
781 }
782
783 // Emit the function descriptor. This is a virtual function to allow targets
784 // to emit their specific function descriptor. Right now it is only used by
785 // the AIX target. The PowerPC 64-bit V1 ELF target also uses function
786 // descriptors and should be converted to use this hook as well.
787 if (MAI->needsFunctionDescriptors())
788 emitFunctionDescriptor();
789
790 // Emit the CurrentFnSym. This is a virtual function to allow targets to do
791 // their wild and crazy things as required.
792 emitFunctionEntryLabel();
793
794 if (CurrentFnBegin) {
795 if (MAI->useAssignmentForEHBegin()) {
796 MCSymbol *CurPos = OutContext.createTempSymbol();
797 OutStreamer->emitLabel(CurPos);
798 OutStreamer->emitAssignment(CurrentFnBegin,
799 MCSymbolRefExpr::create(CurPos, OutContext));
800 } else {
801 OutStreamer->emitLabel(CurrentFnBegin);
802 }
803 }
804
805 // Emit pre-function debug and/or EH information.
806 for (const HandlerInfo &HI : Handlers) {
807 NamedRegionTimer T(HI.TimerName, HI.TimerDescription, HI.TimerGroupName,
808 HI.TimerGroupDescription, TimePassesIsEnabled);
809 HI.Handler->beginFunction(MF);
810 }
811
812 // Emit the prologue data.
813 if (F.hasPrologueData())
814 emitGlobalConstant(F.getParent()->getDataLayout(), F.getPrologueData());
815}
816
817/// EmitFunctionEntryLabel - Emit the label that is the entrypoint for the
818/// function. This can be overridden by targets as required to do custom stuff.
819void AsmPrinter::emitFunctionEntryLabel() {
820 CurrentFnSym->redefineIfPossible();
821
822 // The function label could have already been emitted if two symbols end up
823 // conflicting due to asm renaming. Detect this and emit an error.
824 if (CurrentFnSym->isVariable())
825 report_fatal_error("'" + Twine(CurrentFnSym->getName()) +
826 "' is a protected alias");
827
828 OutStreamer->emitLabel(CurrentFnSym);
829
830 if (TM.getTargetTriple().isOSBinFormatELF()) {
831 MCSymbol *Sym = getSymbolPreferLocal(MF->getFunction());
832 if (Sym != CurrentFnSym)
833 OutStreamer->emitLabel(Sym);
834 }
835}
836
837/// emitComments - Pretty-print comments for instructions.
838static void emitComments(const MachineInstr &MI, raw_ostream &CommentOS) {
839 const MachineFunction *MF = MI.getMF();
840 const TargetInstrInfo *TII = MF->getSubtarget().getInstrInfo();
841
842 // Check for spills and reloads
843
844 // We assume a single instruction only has a spill or reload, not
845 // both.
846 Optional<unsigned> Size;
847 if ((Size = MI.getRestoreSize(TII))) {
848 CommentOS << *Size << "-byte Reload\n";
849 } else if ((Size = MI.getFoldedRestoreSize(TII))) {
850 if (*Size) {
851 if (*Size == unsigned(MemoryLocation::UnknownSize))
852 CommentOS << "Unknown-size Folded Reload\n";
853 else
854 CommentOS << *Size << "-byte Folded Reload\n";
855 }
856 } else if ((Size = MI.getSpillSize(TII))) {
857 CommentOS << *Size << "-byte Spill\n";
858 } else if ((Size = MI.getFoldedSpillSize(TII))) {
859 if (*Size) {
860 if (*Size == unsigned(MemoryLocation::UnknownSize))
861 CommentOS << "Unknown-size Folded Spill\n";
862 else
863 CommentOS << *Size << "-byte Folded Spill\n";
864 }
865 }
866
867 // Check for spill-induced copies
868 if (MI.getAsmPrinterFlag(MachineInstr::ReloadReuse))
869 CommentOS << " Reload Reuse\n";
870}
871
872/// emitImplicitDef - This method emits the specified machine instruction
873/// that is an implicit def.
874void AsmPrinter::emitImplicitDef(const MachineInstr *MI) const {
875 Register RegNo = MI->getOperand(0).getReg();
876
877 SmallString<128> Str;
878 raw_svector_ostream OS(Str);
879 OS << "implicit-def: "
880 << printReg(RegNo, MF->getSubtarget().getRegisterInfo());
881
882 OutStreamer->AddComment(OS.str());
883 OutStreamer->AddBlankLine();
884}
885
886static void emitKill(const MachineInstr *MI, AsmPrinter &AP) {
887 std::string Str;
888 raw_string_ostream OS(Str);
889 OS << "kill:";
890 for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
891 const MachineOperand &Op = MI->getOperand(i);
892 assert(Op.isReg() && "KILL instruction must have only register operands")((Op.isReg() && "KILL instruction must have only register operands"
) ? static_cast<void> (0) : __assert_fail ("Op.isReg() && \"KILL instruction must have only register operands\""
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 892, __PRETTY_FUNCTION__))
;
893 OS << ' ' << (Op.isDef() ? "def " : "killed ")
894 << printReg(Op.getReg(), AP.MF->getSubtarget().getRegisterInfo());
895 }
896 AP.OutStreamer->AddComment(OS.str());
897 AP.OutStreamer->AddBlankLine();
898}
899
900/// emitDebugValueComment - This method handles the target-independent form
901/// of DBG_VALUE, returning true if it was able to do so. A false return
902/// means the target will need to handle MI in EmitInstruction.
903static bool emitDebugValueComment(const MachineInstr *MI, AsmPrinter &AP) {
904 // This code handles only the 4-operand target-independent form.
905 if (MI->isNonListDebugValue() && MI->getNumOperands() != 4)
906 return false;
907
908 SmallString<128> Str;
909 raw_svector_ostream OS(Str);
910 OS << "DEBUG_VALUE: ";
911
912 const DILocalVariable *V = MI->getDebugVariable();
913 if (auto *SP = dyn_cast<DISubprogram>(V->getScope())) {
914 StringRef Name = SP->getName();
915 if (!Name.empty())
916 OS << Name << ":";
917 }
918 OS << V->getName();
919 OS << " <- ";
920
921 const DIExpression *Expr = MI->getDebugExpression();
922 if (Expr->getNumElements()) {
923 OS << '[';
924 ListSeparator LS;
925 for (auto Op : Expr->expr_ops()) {
926 OS << LS << dwarf::OperationEncodingString(Op.getOp());
927 for (unsigned I = 0; I < Op.getNumArgs(); ++I)
928 OS << ' ' << Op.getArg(I);
929 }
930 OS << "] ";
931 }
932
933 // Register or immediate value. Register 0 means undef.
934 for (const MachineOperand &Op : MI->debug_operands()) {
935 if (&Op != MI->debug_operands().begin())
936 OS << ", ";
937 switch (Op.getType()) {
938 case MachineOperand::MO_FPImmediate: {
939 APFloat APF = APFloat(Op.getFPImm()->getValueAPF());
940 if (Op.getFPImm()->getType()->isFloatTy()) {
941 OS << (double)APF.convertToFloat();
942 } else if (Op.getFPImm()->getType()->isDoubleTy()) {
943 OS << APF.convertToDouble();
944 } else {
945 // There is no good way to print long double. Convert a copy to
946 // double. Ah well, it's only a comment.
947 bool ignored;
948 APF.convert(APFloat::IEEEdouble(), APFloat::rmNearestTiesToEven,
949 &ignored);
950 OS << "(long double) " << APF.convertToDouble();
951 }
952 break;
953 }
954 case MachineOperand::MO_Immediate: {
955 OS << Op.getImm();
956 break;
957 }
958 case MachineOperand::MO_CImmediate: {
959 Op.getCImm()->getValue().print(OS, false /*isSigned*/);
960 break;
961 }
962 case MachineOperand::MO_TargetIndex: {
963 OS << "!target-index(" << Op.getIndex() << "," << Op.getOffset() << ")";
964 // NOTE: Want this comment at start of line, don't emit with AddComment.
965 AP.OutStreamer->emitRawComment(OS.str());
966 break;
967 }
968 case MachineOperand::MO_Register:
969 case MachineOperand::MO_FrameIndex: {
970 Register Reg;
971 Optional<StackOffset> Offset;
972 if (Op.isReg()) {
973 Reg = Op.getReg();
974 } else {
975 const TargetFrameLowering *TFI =
976 AP.MF->getSubtarget().getFrameLowering();
977 Offset = TFI->getFrameIndexReference(*AP.MF, Op.getIndex(), Reg);
978 }
979 if (!Reg) {
980 // Suppress offset, it is not meaningful here.
981 OS << "undef";
982 break;
983 }
984 // The second operand is only an offset if it's an immediate.
985 if (MI->isIndirectDebugValue())
986 Offset = StackOffset::getFixed(MI->getDebugOffset().getImm());
987 if (Offset)
988 OS << '[';
989 OS << printReg(Reg, AP.MF->getSubtarget().getRegisterInfo());
990 if (Offset)
991 OS << '+' << Offset->getFixed() << ']';
992 break;
993 }
994 default:
995 llvm_unreachable("Unknown operand type")::llvm::llvm_unreachable_internal("Unknown operand type", "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 995)
;
996 }
997 }
998
999 // NOTE: Want this comment at start of line, don't emit with AddComment.
1000 AP.OutStreamer->emitRawComment(OS.str());
1001 return true;
1002}
1003
1004/// This method handles the target-independent form of DBG_LABEL, returning
1005/// true if it was able to do so. A false return means the target will need
1006/// to handle MI in EmitInstruction.
1007static bool emitDebugLabelComment(const MachineInstr *MI, AsmPrinter &AP) {
1008 if (MI->getNumOperands() != 1)
1009 return false;
1010
1011 SmallString<128> Str;
1012 raw_svector_ostream OS(Str);
1013 OS << "DEBUG_LABEL: ";
1014
1015 const DILabel *V = MI->getDebugLabel();
1016 if (auto *SP = dyn_cast<DISubprogram>(
1017 V->getScope()->getNonLexicalBlockFileScope())) {
1018 StringRef Name = SP->getName();
1019 if (!Name.empty())
1020 OS << Name << ":";
1021 }
1022 OS << V->getName();
1023
1024 // NOTE: Want this comment at start of line, don't emit with AddComment.
1025 AP.OutStreamer->emitRawComment(OS.str());
1026 return true;
1027}
1028
1029AsmPrinter::CFIMoveType AsmPrinter::needsCFIMoves() const {
1030 if (MAI->getExceptionHandlingType() == ExceptionHandling::DwarfCFI &&
1031 MF->getFunction().needsUnwindTableEntry())
1032 return CFI_M_EH;
1033
1034 if (MMI->hasDebugInfo() || MF->getTarget().Options.ForceDwarfFrameSection)
1035 return CFI_M_Debug;
1036
1037 return CFI_M_None;
1038}
1039
1040bool AsmPrinter::needsSEHMoves() {
1041 return MAI->usesWindowsCFI() && MF->getFunction().needsUnwindTableEntry();
1042}
1043
1044void AsmPrinter::emitCFIInstruction(const MachineInstr &MI) {
1045 ExceptionHandling ExceptionHandlingType = MAI->getExceptionHandlingType();
1046 if (ExceptionHandlingType != ExceptionHandling::DwarfCFI &&
1047 ExceptionHandlingType != ExceptionHandling::ARM)
1048 return;
1049
1050 if (needsCFIMoves() == CFI_M_None)
1051 return;
1052
1053 // If there is no "real" instruction following this CFI instruction, skip
1054 // emitting it; it would be beyond the end of the function's FDE range.
1055 auto *MBB = MI.getParent();
1056 auto I = std::next(MI.getIterator());
1057 while (I != MBB->end() && I->isTransient())
1058 ++I;
1059 if (I == MBB->instr_end() &&
1060 MBB->getReverseIterator() == MBB->getParent()->rbegin())
1061 return;
1062
1063 const std::vector<MCCFIInstruction> &Instrs = MF->getFrameInstructions();
1064 unsigned CFIIndex = MI.getOperand(0).getCFIIndex();
1065 const MCCFIInstruction &CFI = Instrs[CFIIndex];
1066 emitCFIInstruction(CFI);
1067}
1068
1069void AsmPrinter::emitFrameAlloc(const MachineInstr &MI) {
1070 // The operands are the MCSymbol and the frame offset of the allocation.
1071 MCSymbol *FrameAllocSym = MI.getOperand(0).getMCSymbol();
1072 int FrameOffset = MI.getOperand(1).getImm();
1073
1074 // Emit a symbol assignment.
1075 OutStreamer->emitAssignment(FrameAllocSym,
1076 MCConstantExpr::create(FrameOffset, OutContext));
1077}
1078
1079/// Returns the BB metadata to be emitted in the .llvm_bb_addr_map section for a
1080/// given basic block. This can be used to capture more precise profile
1081/// information. We use the last 4 bits (LSBs) to encode the following
1082/// information:
1083/// * (1): set if return block (ret or tail call).
1084/// * (2): set if ends with a tail call.
1085/// * (3): set if exception handling (EH) landing pad.
1086/// * (4): set if the block can fall through to its next.
1087/// The remaining bits are zero.
1088static unsigned getBBAddrMapMetadata(const MachineBasicBlock &MBB) {
1089 const TargetInstrInfo *TII = MBB.getParent()->getSubtarget().getInstrInfo();
1090 return ((unsigned)MBB.isReturnBlock()) |
1091 ((!MBB.empty() && TII->isTailCall(MBB.back())) << 1) |
1092 (MBB.isEHPad() << 2) |
1093 (const_cast<MachineBasicBlock &>(MBB).canFallThrough() << 3);
1094}
1095
1096void AsmPrinter::emitBBAddrMapSection(const MachineFunction &MF) {
1097 MCSection *BBAddrMapSection =
1098 getObjFileLowering().getBBAddrMapSection(*MF.getSection());
1099 assert(BBAddrMapSection && ".llvm_bb_addr_map section is not initialized.")((BBAddrMapSection && ".llvm_bb_addr_map section is not initialized."
) ? static_cast<void> (0) : __assert_fail ("BBAddrMapSection && \".llvm_bb_addr_map section is not initialized.\""
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 1099, __PRETTY_FUNCTION__))
;
1100
1101 const MCSymbol *FunctionSymbol = getFunctionBegin();
1102
1103 OutStreamer->PushSection();
1104 OutStreamer->SwitchSection(BBAddrMapSection);
1105 OutStreamer->emitSymbolValue(FunctionSymbol, getPointerSize());
1106 // Emit the total number of basic blocks in this function.
1107 OutStreamer->emitULEB128IntValue(MF.size());
1108 // Emit BB Information for each basic block in the funciton.
1109 for (const MachineBasicBlock &MBB : MF) {
1110 const MCSymbol *MBBSymbol =
1111 MBB.isEntryBlock() ? FunctionSymbol : MBB.getSymbol();
1112 // Emit the basic block offset.
1113 emitLabelDifferenceAsULEB128(MBBSymbol, FunctionSymbol);
1114 // Emit the basic block size. When BBs have alignments, their size cannot
1115 // always be computed from their offsets.
1116 emitLabelDifferenceAsULEB128(MBB.getEndSymbol(), MBBSymbol);
1117 OutStreamer->emitULEB128IntValue(getBBAddrMapMetadata(MBB));
1118 }
1119 OutStreamer->PopSection();
1120}
1121
1122void AsmPrinter::emitPseudoProbe(const MachineInstr &MI) {
1123 auto GUID = MI.getOperand(0).getImm();
1124 auto Index = MI.getOperand(1).getImm();
1125 auto Type = MI.getOperand(2).getImm();
1126 auto Attr = MI.getOperand(3).getImm();
1127 DILocation *DebugLoc = MI.getDebugLoc();
1128 PP->emitPseudoProbe(GUID, Index, Type, Attr, DebugLoc);
1129}
1130
1131void AsmPrinter::emitStackSizeSection(const MachineFunction &MF) {
1132 if (!MF.getTarget().Options.EmitStackSizeSection)
1133 return;
1134
1135 MCSection *StackSizeSection =
1136 getObjFileLowering().getStackSizesSection(*getCurrentSection());
1137 if (!StackSizeSection)
1138 return;
1139
1140 const MachineFrameInfo &FrameInfo = MF.getFrameInfo();
1141 // Don't emit functions with dynamic stack allocations.
1142 if (FrameInfo.hasVarSizedObjects())
1143 return;
1144
1145 OutStreamer->PushSection();
1146 OutStreamer->SwitchSection(StackSizeSection);
1147
1148 const MCSymbol *FunctionSymbol = getFunctionBegin();
1149 uint64_t StackSize = FrameInfo.getStackSize();
1150 OutStreamer->emitSymbolValue(FunctionSymbol, TM.getProgramPointerSize());
1151 OutStreamer->emitULEB128IntValue(StackSize);
1152
1153 OutStreamer->PopSection();
1154}
1155
1156static bool needFuncLabelsForEHOrDebugInfo(const MachineFunction &MF) {
1157 MachineModuleInfo &MMI = MF.getMMI();
1158 if (!MF.getLandingPads().empty() || MF.hasEHFunclets() || MMI.hasDebugInfo())
1159 return true;
1160
1161 // We might emit an EH table that uses function begin and end labels even if
1162 // we don't have any landingpads.
1163 if (!MF.getFunction().hasPersonalityFn())
1164 return false;
1165 return !isNoOpWithoutInvoke(
1166 classifyEHPersonality(MF.getFunction().getPersonalityFn()));
1167}
1168
1169/// EmitFunctionBody - This method emits the body and trailer for a
1170/// function.
1171void AsmPrinter::emitFunctionBody() {
1172 emitFunctionHeader();
1173
1174 // Emit target-specific gunk before the function body.
1175 emitFunctionBodyStart();
1176
1177 if (isVerbose()) {
1178 // Get MachineDominatorTree or compute it on the fly if it's unavailable
1179 MDT = getAnalysisIfAvailable<MachineDominatorTree>();
1180 if (!MDT) {
1181 OwnedMDT = std::make_unique<MachineDominatorTree>();
1182 OwnedMDT->getBase().recalculate(*MF);
1183 MDT = OwnedMDT.get();
1184 }
1185
1186 // Get MachineLoopInfo or compute it on the fly if it's unavailable
1187 MLI = getAnalysisIfAvailable<MachineLoopInfo>();
1188 if (!MLI) {
1189 OwnedMLI = std::make_unique<MachineLoopInfo>();
1190 OwnedMLI->getBase().analyze(MDT->getBase());
1191 MLI = OwnedMLI.get();
1192 }
1193 }
1194
1195 // Print out code for the function.
1196 bool HasAnyRealCode = false;
1197 int NumInstsInFunction = 0;
1198
1199 bool CanDoExtraAnalysis = ORE->allowExtraAnalysis(DEBUG_TYPE"asm-printer");
1200 for (auto &MBB : *MF) {
1201 // Print a label for the basic block.
1202 emitBasicBlockStart(MBB);
1203 DenseMap<StringRef, unsigned> MnemonicCounts;
1204 for (auto &MI : MBB) {
1205 // Print the assembly for the instruction.
1206 if (!MI.isPosition() && !MI.isImplicitDef() && !MI.isKill() &&
1207 !MI.isDebugInstr()) {
1208 HasAnyRealCode = true;
1209 ++NumInstsInFunction;
1210 }
1211
1212 // If there is a pre-instruction symbol, emit a label for it here.
1213 if (MCSymbol *S = MI.getPreInstrSymbol())
1214 OutStreamer->emitLabel(S);
1215
1216 for (const HandlerInfo &HI : Handlers) {
1217 NamedRegionTimer T(HI.TimerName, HI.TimerDescription, HI.TimerGroupName,
1218 HI.TimerGroupDescription, TimePassesIsEnabled);
1219 HI.Handler->beginInstruction(&MI);
1220 }
1221
1222 if (isVerbose())
1223 emitComments(MI, OutStreamer->GetCommentOS());
1224
1225 switch (MI.getOpcode()) {
1226 case TargetOpcode::CFI_INSTRUCTION:
1227 emitCFIInstruction(MI);
1228 break;
1229 case TargetOpcode::LOCAL_ESCAPE:
1230 emitFrameAlloc(MI);
1231 break;
1232 case TargetOpcode::ANNOTATION_LABEL:
1233 case TargetOpcode::EH_LABEL:
1234 case TargetOpcode::GC_LABEL:
1235 OutStreamer->emitLabel(MI.getOperand(0).getMCSymbol());
1236 break;
1237 case TargetOpcode::INLINEASM:
1238 case TargetOpcode::INLINEASM_BR:
1239 emitInlineAsm(&MI);
1240 break;
1241 case TargetOpcode::DBG_VALUE:
1242 case TargetOpcode::DBG_VALUE_LIST:
1243 if (isVerbose()) {
1244 if (!emitDebugValueComment(&MI, *this))
1245 emitInstruction(&MI);
1246 }
1247 break;
1248 case TargetOpcode::DBG_INSTR_REF:
1249 // This instruction reference will have been resolved to a machine
1250 // location, and a nearby DBG_VALUE created. We can safely ignore
1251 // the instruction reference.
1252 break;
1253 case TargetOpcode::DBG_LABEL:
1254 if (isVerbose()) {
1255 if (!emitDebugLabelComment(&MI, *this))
1256 emitInstruction(&MI);
1257 }
1258 break;
1259 case TargetOpcode::IMPLICIT_DEF:
1260 if (isVerbose()) emitImplicitDef(&MI);
1261 break;
1262 case TargetOpcode::KILL:
1263 if (isVerbose()) emitKill(&MI, *this);
1264 break;
1265 case TargetOpcode::PSEUDO_PROBE:
1266 emitPseudoProbe(MI);
1267 break;
1268 default:
1269 emitInstruction(&MI);
1270 if (CanDoExtraAnalysis) {
1271 MCInst MCI;
1272 MCI.setOpcode(MI.getOpcode());
1273 auto Name = OutStreamer->getMnemonic(MCI);
1274 auto I = MnemonicCounts.insert({Name, 0u});
1275 I.first->second++;
1276 }
1277 break;
1278 }
1279
1280 // If there is a post-instruction symbol, emit a label for it here.
1281 if (MCSymbol *S = MI.getPostInstrSymbol())
1282 OutStreamer->emitLabel(S);
1283
1284 for (const HandlerInfo &HI : Handlers) {
1285 NamedRegionTimer T(HI.TimerName, HI.TimerDescription, HI.TimerGroupName,
1286 HI.TimerGroupDescription, TimePassesIsEnabled);
1287 HI.Handler->endInstruction();
1288 }
1289 }
1290
1291 // We must emit temporary symbol for the end of this basic block, if either
1292 // we have BBLabels enabled or if this basic blocks marks the end of a
1293 // section (except the section containing the entry basic block as the end
1294 // symbol for that section is CurrentFnEnd).
1295 if (MF->hasBBLabels() ||
1296 (MAI->hasDotTypeDotSizeDirective() && MBB.isEndSection() &&
1297 !MBB.sameSection(&MF->front())))
1298 OutStreamer->emitLabel(MBB.getEndSymbol());
1299
1300 if (MBB.isEndSection()) {
1301 // The size directive for the section containing the entry block is
1302 // handled separately by the function section.
1303 if (!MBB.sameSection(&MF->front())) {
1304 if (MAI->hasDotTypeDotSizeDirective()) {
1305 // Emit the size directive for the basic block section.
1306 const MCExpr *SizeExp = MCBinaryExpr::createSub(
1307 MCSymbolRefExpr::create(MBB.getEndSymbol(), OutContext),
1308 MCSymbolRefExpr::create(CurrentSectionBeginSym, OutContext),
1309 OutContext);
1310 OutStreamer->emitELFSize(CurrentSectionBeginSym, SizeExp);
1311 }
1312 MBBSectionRanges[MBB.getSectionIDNum()] =
1313 MBBSectionRange{CurrentSectionBeginSym, MBB.getEndSymbol()};
1314 }
1315 }
1316 emitBasicBlockEnd(MBB);
1317
1318 if (CanDoExtraAnalysis) {
1319 // Skip empty blocks.
1320 if (MBB.empty())
1321 continue;
1322
1323 MachineOptimizationRemarkAnalysis R(DEBUG_TYPE"asm-printer", "InstructionMix",
1324 MBB.begin()->getDebugLoc(), &MBB);
1325
1326 // Generate instruction mix remark. First, sort counts in descending order
1327 // by count and name.
1328 SmallVector<std::pair<StringRef, unsigned>, 128> MnemonicVec;
1329 for (auto &KV : MnemonicCounts)
1330 MnemonicVec.emplace_back(KV.first, KV.second);
1331
1332 sort(MnemonicVec, [](const std::pair<StringRef, unsigned> &A,
1333 const std::pair<StringRef, unsigned> &B) {
1334 if (A.second > B.second)
1335 return true;
1336 if (A.second == B.second)
1337 return StringRef(A.first) < StringRef(B.first);
1338 return false;
1339 });
1340 R << "BasicBlock: " << ore::NV("BasicBlock", MBB.getName()) << "\n";
1341 for (auto &KV : MnemonicVec) {
1342 auto Name = (Twine("INST_") + KV.first.trim()).str();
1343 R << KV.first << ": " << ore::NV(Name, KV.second) << "\n";
1344 }
1345 ORE->emit(R);
1346 }
1347 }
1348
1349 EmittedInsts += NumInstsInFunction;
1350 MachineOptimizationRemarkAnalysis R(DEBUG_TYPE"asm-printer", "InstructionCount",
1351 MF->getFunction().getSubprogram(),
1352 &MF->front());
1353 R << ore::NV("NumInstructions", NumInstsInFunction)
1354 << " instructions in function";
1355 ORE->emit(R);
1356
1357 // If the function is empty and the object file uses .subsections_via_symbols,
1358 // then we need to emit *something* to the function body to prevent the
1359 // labels from collapsing together. Just emit a noop.
1360 // Similarly, don't emit empty functions on Windows either. It can lead to
1361 // duplicate entries (two functions with the same RVA) in the Guard CF Table
1362 // after linking, causing the kernel not to load the binary:
1363 // https://developercommunity.visualstudio.com/content/problem/45366/vc-linker-creates-invalid-dll-with-clang-cl.html
1364 // FIXME: Hide this behind some API in e.g. MCAsmInfo or MCTargetStreamer.
1365 const Triple &TT = TM.getTargetTriple();
1366 if (!HasAnyRealCode && (MAI->hasSubsectionsViaSymbols() ||
1367 (TT.isOSWindows() && TT.isOSBinFormatCOFF()))) {
1368 MCInst Noop = MF->getSubtarget().getInstrInfo()->getNop();
1369
1370 // Targets can opt-out of emitting the noop here by leaving the opcode
1371 // unspecified.
1372 if (Noop.getOpcode()) {
1373 OutStreamer->AddComment("avoids zero-length function");
1374 emitNops(1);
1375 }
1376 }
1377
1378 // Switch to the original section in case basic block sections was used.
1379 OutStreamer->SwitchSection(MF->getSection());
1380
1381 const Function &F = MF->getFunction();
1382 for (const auto &BB : F) {
1383 if (!BB.hasAddressTaken())
1384 continue;
1385 MCSymbol *Sym = GetBlockAddressSymbol(&BB);
1386 if (Sym->isDefined())
1387 continue;
1388 OutStreamer->AddComment("Address of block that was removed by CodeGen");
1389 OutStreamer->emitLabel(Sym);
1390 }
1391
1392 // Emit target-specific gunk after the function body.
1393 emitFunctionBodyEnd();
1394
1395 if (needFuncLabelsForEHOrDebugInfo(*MF) ||
1396 MAI->hasDotTypeDotSizeDirective()) {
1397 // Create a symbol for the end of function.
1398 CurrentFnEnd = createTempSymbol("func_end");
1399 OutStreamer->emitLabel(CurrentFnEnd);
1400 }
1401
1402 // If the target wants a .size directive for the size of the function, emit
1403 // it.
1404 if (MAI->hasDotTypeDotSizeDirective()) {
1405 // We can get the size as difference between the function label and the
1406 // temp label.
1407 const MCExpr *SizeExp = MCBinaryExpr::createSub(
1408 MCSymbolRefExpr::create(CurrentFnEnd, OutContext),
1409 MCSymbolRefExpr::create(CurrentFnSymForSize, OutContext), OutContext);
1410 OutStreamer->emitELFSize(CurrentFnSym, SizeExp);
1411 }
1412
1413 for (const HandlerInfo &HI : Handlers) {
1414 NamedRegionTimer T(HI.TimerName, HI.TimerDescription, HI.TimerGroupName,
1415 HI.TimerGroupDescription, TimePassesIsEnabled);
1416 HI.Handler->markFunctionEnd();
1417 }
1418
1419 MBBSectionRanges[MF->front().getSectionIDNum()] =
1420 MBBSectionRange{CurrentFnBegin, CurrentFnEnd};
1421
1422 // Print out jump tables referenced by the function.
1423 emitJumpTableInfo();
1424
1425 // Emit post-function debug and/or EH information.
1426 for (const HandlerInfo &HI : Handlers) {
1427 NamedRegionTimer T(HI.TimerName, HI.TimerDescription, HI.TimerGroupName,
1428 HI.TimerGroupDescription, TimePassesIsEnabled);
1429 HI.Handler->endFunction(MF);
1430 }
1431
1432 // Emit section containing BB address offsets and their metadata, when
1433 // BB labels are requested for this function. Skip empty functions.
1434 if (MF->hasBBLabels() && HasAnyRealCode)
1435 emitBBAddrMapSection(*MF);
1436
1437 // Emit section containing stack size metadata.
1438 emitStackSizeSection(*MF);
1439
1440 emitPatchableFunctionEntries();
1441
1442 if (isVerbose())
1443 OutStreamer->GetCommentOS() << "-- End function\n";
1444
1445 OutStreamer->AddBlankLine();
1446}
1447
1448/// Compute the number of Global Variables that uses a Constant.
1449static unsigned getNumGlobalVariableUses(const Constant *C) {
1450 if (!C)
1451 return 0;
1452
1453 if (isa<GlobalVariable>(C))
1454 return 1;
1455
1456 unsigned NumUses = 0;
1457 for (auto *CU : C->users())
1458 NumUses += getNumGlobalVariableUses(dyn_cast<Constant>(CU));
1459
1460 return NumUses;
1461}
1462
1463/// Only consider global GOT equivalents if at least one user is a
1464/// cstexpr inside an initializer of another global variables. Also, don't
1465/// handle cstexpr inside instructions. During global variable emission,
1466/// candidates are skipped and are emitted later in case at least one cstexpr
1467/// isn't replaced by a PC relative GOT entry access.
1468static bool isGOTEquivalentCandidate(const GlobalVariable *GV,
1469 unsigned &NumGOTEquivUsers) {
1470 // Global GOT equivalents are unnamed private globals with a constant
1471 // pointer initializer to another global symbol. They must point to a
1472 // GlobalVariable or Function, i.e., as GlobalValue.
1473 if (!GV->hasGlobalUnnamedAddr() || !GV->hasInitializer() ||
1474 !GV->isConstant() || !GV->isDiscardableIfUnused() ||
1475 !isa<GlobalValue>(GV->getOperand(0)))
1476 return false;
1477
1478 // To be a got equivalent, at least one of its users need to be a constant
1479 // expression used by another global variable.
1480 for (auto *U : GV->users())
1481 NumGOTEquivUsers += getNumGlobalVariableUses(dyn_cast<Constant>(U));
1482
1483 return NumGOTEquivUsers > 0;
1484}
1485
1486/// Unnamed constant global variables solely contaning a pointer to
1487/// another globals variable is equivalent to a GOT table entry; it contains the
1488/// the address of another symbol. Optimize it and replace accesses to these
1489/// "GOT equivalents" by using the GOT entry for the final global instead.
1490/// Compute GOT equivalent candidates among all global variables to avoid
1491/// emitting them if possible later on, after it use is replaced by a GOT entry
1492/// access.
1493void AsmPrinter::computeGlobalGOTEquivs(Module &M) {
1494 if (!getObjFileLowering().supportIndirectSymViaGOTPCRel())
1495 return;
1496
1497 for (const auto &G : M.globals()) {
1498 unsigned NumGOTEquivUsers = 0;
1499 if (!isGOTEquivalentCandidate(&G, NumGOTEquivUsers))
1500 continue;
1501
1502 const MCSymbol *GOTEquivSym = getSymbol(&G);
1503 GlobalGOTEquivs[GOTEquivSym] = std::make_pair(&G, NumGOTEquivUsers);
1504 }
1505}
1506
1507/// Constant expressions using GOT equivalent globals may not be eligible
1508/// for PC relative GOT entry conversion, in such cases we need to emit such
1509/// globals we previously omitted in EmitGlobalVariable.
1510void AsmPrinter::emitGlobalGOTEquivs() {
1511 if (!getObjFileLowering().supportIndirectSymViaGOTPCRel())
1512 return;
1513
1514 SmallVector<const GlobalVariable *, 8> FailedCandidates;
1515 for (auto &I : GlobalGOTEquivs) {
1516 const GlobalVariable *GV = I.second.first;
1517 unsigned Cnt = I.second.second;
1518 if (Cnt)
1519 FailedCandidates.push_back(GV);
1520 }
1521 GlobalGOTEquivs.clear();
1522
1523 for (auto *GV : FailedCandidates)
1524 emitGlobalVariable(GV);
1525}
1526
1527void AsmPrinter::emitGlobalIndirectSymbol(Module &M,
1528 const GlobalIndirectSymbol& GIS) {
1529 MCSymbol *Name = getSymbol(&GIS);
1530 bool IsFunction = GIS.getValueType()->isFunctionTy();
1531 // Treat bitcasts of functions as functions also. This is important at least
1532 // on WebAssembly where object and function addresses can't alias each other.
1533 if (!IsFunction)
1534 if (auto *CE = dyn_cast<ConstantExpr>(GIS.getIndirectSymbol()))
1535 if (CE->getOpcode() == Instruction::BitCast)
1536 IsFunction =
1537 CE->getOperand(0)->getType()->getPointerElementType()->isFunctionTy();
1538
1539 // AIX's assembly directive `.set` is not usable for aliasing purpose,
1540 // so AIX has to use the extra-label-at-definition strategy. At this
1541 // point, all the extra label is emitted, we just have to emit linkage for
1542 // those labels.
1543 if (TM.getTargetTriple().isOSBinFormatXCOFF()) {
1544 assert(!isa<GlobalIFunc>(GIS) && "IFunc is not supported on AIX.")((!isa<GlobalIFunc>(GIS) && "IFunc is not supported on AIX."
) ? static_cast<void> (0) : __assert_fail ("!isa<GlobalIFunc>(GIS) && \"IFunc is not supported on AIX.\""
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 1544, __PRETTY_FUNCTION__))
;
1545 assert(MAI->hasVisibilityOnlyWithLinkage() &&((MAI->hasVisibilityOnlyWithLinkage() && "Visibility should be handled with emitLinkage() on AIX."
) ? static_cast<void> (0) : __assert_fail ("MAI->hasVisibilityOnlyWithLinkage() && \"Visibility should be handled with emitLinkage() on AIX.\""
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 1546, __PRETTY_FUNCTION__))
1546 "Visibility should be handled with emitLinkage() on AIX.")((MAI->hasVisibilityOnlyWithLinkage() && "Visibility should be handled with emitLinkage() on AIX."
) ? static_cast<void> (0) : __assert_fail ("MAI->hasVisibilityOnlyWithLinkage() && \"Visibility should be handled with emitLinkage() on AIX.\""
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 1546, __PRETTY_FUNCTION__))
;
1547 emitLinkage(&GIS, Name);
1548 // If it's a function, also emit linkage for aliases of function entry
1549 // point.
1550 if (IsFunction)
1551 emitLinkage(&GIS,
1552 getObjFileLowering().getFunctionEntryPointSymbol(&GIS, TM));
1553 return;
1554 }
1555
1556 if (GIS.hasExternalLinkage() || !MAI->getWeakRefDirective())
1557 OutStreamer->emitSymbolAttribute(Name, MCSA_Global);
1558 else if (GIS.hasWeakLinkage() || GIS.hasLinkOnceLinkage())
1559 OutStreamer->emitSymbolAttribute(Name, MCSA_WeakReference);
1560 else
1561 assert(GIS.hasLocalLinkage() && "Invalid alias or ifunc linkage")((GIS.hasLocalLinkage() && "Invalid alias or ifunc linkage"
) ? static_cast<void> (0) : __assert_fail ("GIS.hasLocalLinkage() && \"Invalid alias or ifunc linkage\""
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 1561, __PRETTY_FUNCTION__))
;
1562
1563 // Set the symbol type to function if the alias has a function type.
1564 // This affects codegen when the aliasee is not a function.
1565 if (IsFunction)
1566 OutStreamer->emitSymbolAttribute(Name, isa<GlobalIFunc>(GIS)
1567 ? MCSA_ELF_TypeIndFunction
1568 : MCSA_ELF_TypeFunction);
1569
1570 emitVisibility(Name, GIS.getVisibility());
1571
1572 const MCExpr *Expr = lowerConstant(GIS.getIndirectSymbol());
1573
1574 if (isa<GlobalAlias>(&GIS) && MAI->hasAltEntry() && isa<MCBinaryExpr>(Expr))
1575 OutStreamer->emitSymbolAttribute(Name, MCSA_AltEntry);
1576
1577 // Emit the directives as assignments aka .set:
1578 OutStreamer->emitAssignment(Name, Expr);
1579 MCSymbol *LocalAlias = getSymbolPreferLocal(GIS);
1580 if (LocalAlias != Name)
1581 OutStreamer->emitAssignment(LocalAlias, Expr);
1582
1583 if (auto *GA = dyn_cast<GlobalAlias>(&GIS)) {
1584 // If the aliasee does not correspond to a symbol in the output, i.e. the
1585 // alias is not of an object or the aliased object is private, then set the
1586 // size of the alias symbol from the type of the alias. We don't do this in
1587 // other situations as the alias and aliasee having differing types but same
1588 // size may be intentional.
1589 const GlobalObject *BaseObject = GA->getBaseObject();
1590 if (MAI->hasDotTypeDotSizeDirective() && GA->getValueType()->isSized() &&
1591 (!BaseObject || BaseObject->hasPrivateLinkage())) {
1592 const DataLayout &DL = M.getDataLayout();
1593 uint64_t Size = DL.getTypeAllocSize(GA->getValueType());
1594 OutStreamer->emitELFSize(Name, MCConstantExpr::create(Size, OutContext));
1595 }
1596 }
1597}
1598
1599void AsmPrinter::emitRemarksSection(remarks::RemarkStreamer &RS) {
1600 if (!RS.needsSection())
1601 return;
1602
1603 remarks::RemarkSerializer &RemarkSerializer = RS.getSerializer();
1604
1605 Optional<SmallString<128>> Filename;
1606 if (Optional<StringRef> FilenameRef = RS.getFilename()) {
1607 Filename = *FilenameRef;
1608 sys::fs::make_absolute(*Filename);
1609 assert(!Filename->empty() && "The filename can't be empty.")((!Filename->empty() && "The filename can't be empty."
) ? static_cast<void> (0) : __assert_fail ("!Filename->empty() && \"The filename can't be empty.\""
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 1609, __PRETTY_FUNCTION__))
;
1610 }
1611
1612 std::string Buf;
1613 raw_string_ostream OS(Buf);
1614 std::unique_ptr<remarks::MetaSerializer> MetaSerializer =
1615 Filename ? RemarkSerializer.metaSerializer(OS, StringRef(*Filename))
1616 : RemarkSerializer.metaSerializer(OS);
1617 MetaSerializer->emit();
1618
1619 // Switch to the remarks section.
1620 MCSection *RemarksSection =
1621 OutContext.getObjectFileInfo()->getRemarksSection();
1622 OutStreamer->SwitchSection(RemarksSection);
1623
1624 OutStreamer->emitBinaryData(OS.str());
1625}
1626
1627bool AsmPrinter::doFinalization(Module &M) {
1628 // Set the MachineFunction to nullptr so that we can catch attempted
1629 // accesses to MF specific features at the module level and so that
1630 // we can conditionalize accesses based on whether or not it is nullptr.
1631 MF = nullptr;
1632
1633 // Gather all GOT equivalent globals in the module. We really need two
1634 // passes over the globals: one to compute and another to avoid its emission
1635 // in EmitGlobalVariable, otherwise we would not be able to handle cases
1636 // where the got equivalent shows up before its use.
1637 computeGlobalGOTEquivs(M);
1638
1639 // Emit global variables.
1640 for (const auto &G : M.globals())
1641 emitGlobalVariable(&G);
1642
1643 // Emit remaining GOT equivalent globals.
1644 emitGlobalGOTEquivs();
1645
1646 const TargetLoweringObjectFile &TLOF = getObjFileLowering();
1647
1648 // Emit linkage(XCOFF) and visibility info for declarations
1649 for (const Function &F : M) {
1650 if (!F.isDeclarationForLinker())
1651 continue;
1652
1653 MCSymbol *Name = getSymbol(&F);
1654 // Function getSymbol gives us the function descriptor symbol for XCOFF.
1655
1656 if (!TM.getTargetTriple().isOSBinFormatXCOFF()) {
1657 GlobalValue::VisibilityTypes V = F.getVisibility();
1658 if (V == GlobalValue::DefaultVisibility)
1659 continue;
1660
1661 emitVisibility(Name, V, false);
1662 continue;
1663 }
1664
1665 if (F.isIntrinsic())
1666 continue;
1667
1668 // Handle the XCOFF case.
1669 // Variable `Name` is the function descriptor symbol (see above). Get the
1670 // function entry point symbol.
1671 MCSymbol *FnEntryPointSym = TLOF.getFunctionEntryPointSymbol(&F, TM);
1672 // Emit linkage for the function entry point.
1673 emitLinkage(&F, FnEntryPointSym);
1674
1675 // Emit linkage for the function descriptor.
1676 emitLinkage(&F, Name);
1677 }
1678
1679 // Emit the remarks section contents.
1680 // FIXME: Figure out when is the safest time to emit this section. It should
1681 // not come after debug info.
1682 if (remarks::RemarkStreamer *RS = M.getContext().getMainRemarkStreamer())
1683 emitRemarksSection(*RS);
1684
1685 TLOF.emitModuleMetadata(*OutStreamer, M);
1686
1687 if (TM.getTargetTriple().isOSBinFormatELF()) {
1688 MachineModuleInfoELF &MMIELF = MMI->getObjFileInfo<MachineModuleInfoELF>();
1689
1690 // Output stubs for external and common global variables.
1691 MachineModuleInfoELF::SymbolListTy Stubs = MMIELF.GetGVStubList();
1692 if (!Stubs.empty()) {
1693 OutStreamer->SwitchSection(TLOF.getDataSection());
1694 const DataLayout &DL = M.getDataLayout();
1695
1696 emitAlignment(Align(DL.getPointerSize()));
1697 for (const auto &Stub : Stubs) {
1698 OutStreamer->emitLabel(Stub.first);
1699 OutStreamer->emitSymbolValue(Stub.second.getPointer(),
1700 DL.getPointerSize());
1701 }
1702 }
1703 }
1704
1705 if (TM.getTargetTriple().isOSBinFormatCOFF()) {
1706 MachineModuleInfoCOFF &MMICOFF =
1707 MMI->getObjFileInfo<MachineModuleInfoCOFF>();
1708
1709 // Output stubs for external and common global variables.
1710 MachineModuleInfoCOFF::SymbolListTy Stubs = MMICOFF.GetGVStubList();
1711 if (!Stubs.empty()) {
1712 const DataLayout &DL = M.getDataLayout();
1713
1714 for (const auto &Stub : Stubs) {
1715 SmallString<256> SectionName = StringRef(".rdata$");
1716 SectionName += Stub.first->getName();
1717 OutStreamer->SwitchSection(OutContext.getCOFFSection(
1718 SectionName,
1719 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ |
1720 COFF::IMAGE_SCN_LNK_COMDAT,
1721 SectionKind::getReadOnly(), Stub.first->getName(),
1722 COFF::IMAGE_COMDAT_SELECT_ANY));
1723 emitAlignment(Align(DL.getPointerSize()));
1724 OutStreamer->emitSymbolAttribute(Stub.first, MCSA_Global);
1725 OutStreamer->emitLabel(Stub.first);
1726 OutStreamer->emitSymbolValue(Stub.second.getPointer(),
1727 DL.getPointerSize());
1728 }
1729 }
1730 }
1731
1732 // Finalize debug and EH information.
1733 for (const HandlerInfo &HI : Handlers) {
1734 NamedRegionTimer T(HI.TimerName, HI.TimerDescription, HI.TimerGroupName,
1735 HI.TimerGroupDescription, TimePassesIsEnabled);
1736 HI.Handler->endModule();
1737 }
1738
1739 // This deletes all the ephemeral handlers that AsmPrinter added, while
1740 // keeping all the user-added handlers alive until the AsmPrinter is
1741 // destroyed.
1742 Handlers.erase(Handlers.begin() + NumUserHandlers, Handlers.end());
1743 DD = nullptr;
1744
1745 // If the target wants to know about weak references, print them all.
1746 if (MAI->getWeakRefDirective()) {
1747 // FIXME: This is not lazy, it would be nice to only print weak references
1748 // to stuff that is actually used. Note that doing so would require targets
1749 // to notice uses in operands (due to constant exprs etc). This should
1750 // happen with the MC stuff eventually.
1751
1752 // Print out module-level global objects here.
1753 for (const auto &GO : M.global_objects()) {
1754 if (!GO.hasExternalWeakLinkage())
1755 continue;
1756 OutStreamer->emitSymbolAttribute(getSymbol(&GO), MCSA_WeakReference);
1757 }
1758 }
1759
1760 // Print aliases in topological order, that is, for each alias a = b,
1761 // b must be printed before a.
1762 // This is because on some targets (e.g. PowerPC) linker expects aliases in
1763 // such an order to generate correct TOC information.
1764 SmallVector<const GlobalAlias *, 16> AliasStack;
1765 SmallPtrSet<const GlobalAlias *, 16> AliasVisited;
1766 for (const auto &Alias : M.aliases()) {
1767 for (const GlobalAlias *Cur = &Alias; Cur;
1768 Cur = dyn_cast<GlobalAlias>(Cur->getAliasee())) {
1769 if (!AliasVisited.insert(Cur).second)
1770 break;
1771 AliasStack.push_back(Cur);
1772 }
1773 for (const GlobalAlias *AncestorAlias : llvm::reverse(AliasStack))
1774 emitGlobalIndirectSymbol(M, *AncestorAlias);
1775 AliasStack.clear();
1776 }
1777 for (const auto &IFunc : M.ifuncs())
1778 emitGlobalIndirectSymbol(M, IFunc);
1779
1780 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
1781 assert(MI && "AsmPrinter didn't require GCModuleInfo?")((MI && "AsmPrinter didn't require GCModuleInfo?") ? static_cast
<void> (0) : __assert_fail ("MI && \"AsmPrinter didn't require GCModuleInfo?\""
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 1781, __PRETTY_FUNCTION__))
;
1782 for (GCModuleInfo::iterator I = MI->end(), E = MI->begin(); I != E; )
1783 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(**--I))
1784 MP->finishAssembly(M, *MI, *this);
1785
1786 // Emit llvm.ident metadata in an '.ident' directive.
1787 emitModuleIdents(M);
1788
1789 // Emit bytes for llvm.commandline metadata.
1790 emitModuleCommandLines(M);
1791
1792 // Emit __morestack address if needed for indirect calls.
1793 if (MMI->usesMorestackAddr()) {
1794 Align Alignment(1);
1795 MCSection *ReadOnlySection = getObjFileLowering().getSectionForConstant(
1796 getDataLayout(), SectionKind::getReadOnly(),
1797 /*C=*/nullptr, Alignment);
1798 OutStreamer->SwitchSection(ReadOnlySection);
1799
1800 MCSymbol *AddrSymbol =
1801 OutContext.getOrCreateSymbol(StringRef("__morestack_addr"));
1802 OutStreamer->emitLabel(AddrSymbol);
1803
1804 unsigned PtrSize = MAI->getCodePointerSize();
1805 OutStreamer->emitSymbolValue(GetExternalSymbolSymbol("__morestack"),
1806 PtrSize);
1807 }
1808
1809 // Emit .note.GNU-split-stack and .note.GNU-no-split-stack sections if
1810 // split-stack is used.
1811 if (TM.getTargetTriple().isOSBinFormatELF() && MMI->hasSplitStack()) {
1812 OutStreamer->SwitchSection(
1813 OutContext.getELFSection(".note.GNU-split-stack", ELF::SHT_PROGBITS, 0));
1814 if (MMI->hasNosplitStack())
1815 OutStreamer->SwitchSection(
1816 OutContext.getELFSection(".note.GNU-no-split-stack", ELF::SHT_PROGBITS, 0));
1817 }
1818
1819 // If we don't have any trampolines, then we don't require stack memory
1820 // to be executable. Some targets have a directive to declare this.
1821 Function *InitTrampolineIntrinsic = M.getFunction("llvm.init.trampoline");
1822 if (!InitTrampolineIntrinsic || InitTrampolineIntrinsic->use_empty())
1823 if (MCSection *S = MAI->getNonexecutableStackSection(OutContext))
1824 OutStreamer->SwitchSection(S);
1825
1826 if (TM.Options.EmitAddrsig) {
1827 // Emit address-significance attributes for all globals.
1828 OutStreamer->emitAddrsig();
1829 for (const GlobalValue &GV : M.global_values())
1830 if (!GV.use_empty() && !GV.isThreadLocal() &&
1831 !GV.hasDLLImportStorageClass() && !GV.getName().startswith("llvm.") &&
1832 !GV.hasAtLeastLocalUnnamedAddr())
1833 OutStreamer->emitAddrsigSym(getSymbol(&GV));
1834 }
1835
1836 // Emit symbol partition specifications (ELF only).
1837 if (TM.getTargetTriple().isOSBinFormatELF()) {
1838 unsigned UniqueID = 0;
1839 for (const GlobalValue &GV : M.global_values()) {
1840 if (!GV.hasPartition() || GV.isDeclarationForLinker() ||
1841 GV.getVisibility() != GlobalValue::DefaultVisibility)
1842 continue;
1843
1844 OutStreamer->SwitchSection(
1845 OutContext.getELFSection(".llvm_sympart", ELF::SHT_LLVM_SYMPART, 0, 0,
1846 "", false, ++UniqueID, nullptr));
1847 OutStreamer->emitBytes(GV.getPartition());
1848 OutStreamer->emitZeros(1);
1849 OutStreamer->emitValue(
1850 MCSymbolRefExpr::create(getSymbol(&GV), OutContext),
1851 MAI->getCodePointerSize());
1852 }
1853 }
1854
1855 // Allow the target to emit any magic that it wants at the end of the file,
1856 // after everything else has gone out.
1857 emitEndOfAsmFile(M);
1858
1859 MMI = nullptr;
1860
1861 OutStreamer->Finish();
1862 OutStreamer->reset();
1863 OwnedMLI.reset();
1864 OwnedMDT.reset();
1865
1866 return false;
1867}
1868
1869MCSymbol *AsmPrinter::getMBBExceptionSym(const MachineBasicBlock &MBB) {
1870 auto Res = MBBSectionExceptionSyms.try_emplace(MBB.getSectionIDNum());
1871 if (Res.second)
1872 Res.first->second = createTempSymbol("exception");
1873 return Res.first->second;
1874}
1875
1876void AsmPrinter::SetupMachineFunction(MachineFunction &MF) {
1877 this->MF = &MF;
1878 const Function &F = MF.getFunction();
1879
1880 // Get the function symbol.
1881 if (!MAI->needsFunctionDescriptors()) {
1882 CurrentFnSym = getSymbol(&MF.getFunction());
1883 } else {
1884 assert(TM.getTargetTriple().isOSAIX() &&((TM.getTargetTriple().isOSAIX() && "Only AIX uses the function descriptor hooks."
) ? static_cast<void> (0) : __assert_fail ("TM.getTargetTriple().isOSAIX() && \"Only AIX uses the function descriptor hooks.\""
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 1885, __PRETTY_FUNCTION__))
1885 "Only AIX uses the function descriptor hooks.")((TM.getTargetTriple().isOSAIX() && "Only AIX uses the function descriptor hooks."
) ? static_cast<void> (0) : __assert_fail ("TM.getTargetTriple().isOSAIX() && \"Only AIX uses the function descriptor hooks.\""
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 1885, __PRETTY_FUNCTION__))
;
1886 // AIX is unique here in that the name of the symbol emitted for the
1887 // function body does not have the same name as the source function's
1888 // C-linkage name.
1889 assert(CurrentFnDescSym && "The function descriptor symbol needs to be"((CurrentFnDescSym && "The function descriptor symbol needs to be"
" initalized first.") ? static_cast<void> (0) : __assert_fail
("CurrentFnDescSym && \"The function descriptor symbol needs to be\" \" initalized first.\""
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 1890, __PRETTY_FUNCTION__))
1890 " initalized first.")((CurrentFnDescSym && "The function descriptor symbol needs to be"
" initalized first.") ? static_cast<void> (0) : __assert_fail
("CurrentFnDescSym && \"The function descriptor symbol needs to be\" \" initalized first.\""
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 1890, __PRETTY_FUNCTION__))
;
1891
1892 // Get the function entry point symbol.
1893 CurrentFnSym = getObjFileLowering().getFunctionEntryPointSymbol(&F, TM);
1894 }
1895
1896 CurrentFnSymForSize = CurrentFnSym;
1897 CurrentFnBegin = nullptr;
1898 CurrentSectionBeginSym = nullptr;
1899 MBBSectionRanges.clear();
1900 MBBSectionExceptionSyms.clear();
1901 bool NeedsLocalForSize = MAI->needsLocalForSize();
1902 if (F.hasFnAttribute("patchable-function-entry") ||
1903 F.hasFnAttribute("function-instrument") ||
1904 F.hasFnAttribute("xray-instruction-threshold") ||
1905 needFuncLabelsForEHOrDebugInfo(MF) || NeedsLocalForSize ||
1906 MF.getTarget().Options.EmitStackSizeSection || MF.hasBBLabels()) {
1907 CurrentFnBegin = createTempSymbol("func_begin");
1908 if (NeedsLocalForSize)
1909 CurrentFnSymForSize = CurrentFnBegin;
1910 }
1911
1912 ORE = &getAnalysis<MachineOptimizationRemarkEmitterPass>().getORE();
1913}
1914
1915namespace {
1916
1917// Keep track the alignment, constpool entries per Section.
1918 struct SectionCPs {
1919 MCSection *S;
1920 Align Alignment;
1921 SmallVector<unsigned, 4> CPEs;
1922
1923 SectionCPs(MCSection *s, Align a) : S(s), Alignment(a) {}
1924 };
1925
1926} // end anonymous namespace
1927
1928/// EmitConstantPool - Print to the current output stream assembly
1929/// representations of the constants in the constant pool MCP. This is
1930/// used to print out constants which have been "spilled to memory" by
1931/// the code generator.
1932void AsmPrinter::emitConstantPool() {
1933 const MachineConstantPool *MCP = MF->getConstantPool();
1934 const std::vector<MachineConstantPoolEntry> &CP = MCP->getConstants();
1935 if (CP.empty()) return;
1936
1937 // Calculate sections for constant pool entries. We collect entries to go into
1938 // the same section together to reduce amount of section switch statements.
1939 SmallVector<SectionCPs, 4> CPSections;
1940 for (unsigned i = 0, e = CP.size(); i != e; ++i) {
1941 const MachineConstantPoolEntry &CPE = CP[i];
1942 Align Alignment = CPE.getAlign();
1943
1944 SectionKind Kind = CPE.getSectionKind(&getDataLayout());
1945
1946 const Constant *C = nullptr;
1947 if (!CPE.isMachineConstantPoolEntry())
1948 C = CPE.Val.ConstVal;
1949
1950 MCSection *S = getObjFileLowering().getSectionForConstant(
1951 getDataLayout(), Kind, C, Alignment);
1952
1953 // The number of sections are small, just do a linear search from the
1954 // last section to the first.
1955 bool Found = false;
1956 unsigned SecIdx = CPSections.size();
1957 while (SecIdx != 0) {
1958 if (CPSections[--SecIdx].S == S) {
1959 Found = true;
1960 break;
1961 }
1962 }
1963 if (!Found) {
1964 SecIdx = CPSections.size();
1965 CPSections.push_back(SectionCPs(S, Alignment));
1966 }
1967
1968 if (Alignment > CPSections[SecIdx].Alignment)
1969 CPSections[SecIdx].Alignment = Alignment;
1970 CPSections[SecIdx].CPEs.push_back(i);
1971 }
1972
1973 // Now print stuff into the calculated sections.
1974 const MCSection *CurSection = nullptr;
1975 unsigned Offset = 0;
1976 for (unsigned i = 0, e = CPSections.size(); i != e; ++i) {
1977 for (unsigned j = 0, ee = CPSections[i].CPEs.size(); j != ee; ++j) {
1978 unsigned CPI = CPSections[i].CPEs[j];
1979 MCSymbol *Sym = GetCPISymbol(CPI);
1980 if (!Sym->isUndefined())
1981 continue;
1982
1983 if (CurSection != CPSections[i].S) {
1984 OutStreamer->SwitchSection(CPSections[i].S);
1985 emitAlignment(Align(CPSections[i].Alignment));
1986 CurSection = CPSections[i].S;
1987 Offset = 0;
1988 }
1989
1990 MachineConstantPoolEntry CPE = CP[CPI];
1991
1992 // Emit inter-object padding for alignment.
1993 unsigned NewOffset = alignTo(Offset, CPE.getAlign());
1994 OutStreamer->emitZeros(NewOffset - Offset);
1995
1996 Offset = NewOffset + CPE.getSizeInBytes(getDataLayout());
1997
1998 OutStreamer->emitLabel(Sym);
1999 if (CPE.isMachineConstantPoolEntry())
2000 emitMachineConstantPoolValue(CPE.Val.MachineCPVal);
2001 else
2002 emitGlobalConstant(getDataLayout(), CPE.Val.ConstVal);
2003 }
2004 }
2005}
2006
2007// Print assembly representations of the jump tables used by the current
2008// function.
2009void AsmPrinter::emitJumpTableInfo() {
2010 const DataLayout &DL = MF->getDataLayout();
2011 const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo();
2012 if (!MJTI) return;
2013 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_Inline) return;
2014 const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
2015 if (JT.empty()) return;
2016
2017 // Pick the directive to use to print the jump table entries, and switch to
2018 // the appropriate section.
2019 const Function &F = MF->getFunction();
2020 const TargetLoweringObjectFile &TLOF = getObjFileLowering();
2021 bool JTInDiffSection = !TLOF.shouldPutJumpTableInFunctionSection(
2022 MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32,
2023 F);
2024 if (JTInDiffSection) {
2025 // Drop it in the readonly section.
2026 MCSection *ReadOnlySection = TLOF.getSectionForJumpTable(F, TM);
2027 OutStreamer->SwitchSection(ReadOnlySection);
2028 }
2029
2030 emitAlignment(Align(MJTI->getEntryAlignment(DL)));
2031
2032 // Jump tables in code sections are marked with a data_region directive
2033 // where that's supported.
2034 if (!JTInDiffSection)
2035 OutStreamer->emitDataRegion(MCDR_DataRegionJT32);
2036
2037 for (unsigned JTI = 0, e = JT.size(); JTI != e; ++JTI) {
2038 const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs;
2039
2040 // If this jump table was deleted, ignore it.
2041 if (JTBBs.empty()) continue;
2042
2043 // For the EK_LabelDifference32 entry, if using .set avoids a relocation,
2044 /// emit a .set directive for each unique entry.
2045 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 &&
2046 MAI->doesSetDirectiveSuppressReloc()) {
2047 SmallPtrSet<const MachineBasicBlock*, 16> EmittedSets;
2048 const TargetLowering *TLI = MF->getSubtarget().getTargetLowering();
2049 const MCExpr *Base = TLI->getPICJumpTableRelocBaseExpr(MF,JTI,OutContext);
2050 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii) {
2051 const MachineBasicBlock *MBB = JTBBs[ii];
2052 if (!EmittedSets.insert(MBB).second)
2053 continue;
2054
2055 // .set LJTSet, LBB32-base
2056 const MCExpr *LHS =
2057 MCSymbolRefExpr::create(MBB->getSymbol(), OutContext);
2058 OutStreamer->emitAssignment(GetJTSetSymbol(JTI, MBB->getNumber()),
2059 MCBinaryExpr::createSub(LHS, Base,
2060 OutContext));
2061 }
2062 }
2063
2064 // On some targets (e.g. Darwin) we want to emit two consecutive labels
2065 // before each jump table. The first label is never referenced, but tells
2066 // the assembler and linker the extents of the jump table object. The
2067 // second label is actually referenced by the code.
2068 if (JTInDiffSection && DL.hasLinkerPrivateGlobalPrefix())
2069 // FIXME: This doesn't have to have any specific name, just any randomly
2070 // named and numbered local label started with 'l' would work. Simplify
2071 // GetJTISymbol.
2072 OutStreamer->emitLabel(GetJTISymbol(JTI, true));
2073
2074 MCSymbol* JTISymbol = GetJTISymbol(JTI);
2075 OutStreamer->emitLabel(JTISymbol);
2076
2077 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii)
2078 emitJumpTableEntry(MJTI, JTBBs[ii], JTI);
2079 }
2080 if (!JTInDiffSection)
2081 OutStreamer->emitDataRegion(MCDR_DataRegionEnd);
2082}
2083
2084/// EmitJumpTableEntry - Emit a jump table entry for the specified MBB to the
2085/// current stream.
2086void AsmPrinter::emitJumpTableEntry(const MachineJumpTableInfo *MJTI,
2087 const MachineBasicBlock *MBB,
2088 unsigned UID) const {
2089 assert(MBB && MBB->getNumber() >= 0 && "Invalid basic block")((MBB && MBB->getNumber() >= 0 && "Invalid basic block"
) ? static_cast<void> (0) : __assert_fail ("MBB && MBB->getNumber() >= 0 && \"Invalid basic block\""
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 2089, __PRETTY_FUNCTION__))
;
2090 const MCExpr *Value = nullptr;
2091 switch (MJTI->getEntryKind()) {
2092 case MachineJumpTableInfo::EK_Inline:
2093 llvm_unreachable("Cannot emit EK_Inline jump table entry")::llvm::llvm_unreachable_internal("Cannot emit EK_Inline jump table entry"
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 2093)
;
2094 case MachineJumpTableInfo::EK_Custom32:
2095 Value = MF->getSubtarget().getTargetLowering()->LowerCustomJumpTableEntry(
2096 MJTI, MBB, UID, OutContext);
2097 break;
2098 case MachineJumpTableInfo::EK_BlockAddress:
2099 // EK_BlockAddress - Each entry is a plain address of block, e.g.:
2100 // .word LBB123
2101 Value = MCSymbolRefExpr::create(MBB->getSymbol(), OutContext);
2102 break;
2103 case MachineJumpTableInfo::EK_GPRel32BlockAddress: {
2104 // EK_GPRel32BlockAddress - Each entry is an address of block, encoded
2105 // with a relocation as gp-relative, e.g.:
2106 // .gprel32 LBB123
2107 MCSymbol *MBBSym = MBB->getSymbol();
2108 OutStreamer->emitGPRel32Value(MCSymbolRefExpr::create(MBBSym, OutContext));
2109 return;
2110 }
2111
2112 case MachineJumpTableInfo::EK_GPRel64BlockAddress: {
2113 // EK_GPRel64BlockAddress - Each entry is an address of block, encoded
2114 // with a relocation as gp-relative, e.g.:
2115 // .gpdword LBB123
2116 MCSymbol *MBBSym = MBB->getSymbol();
2117 OutStreamer->emitGPRel64Value(MCSymbolRefExpr::create(MBBSym, OutContext));
2118 return;
2119 }
2120
2121 case MachineJumpTableInfo::EK_LabelDifference32: {
2122 // Each entry is the address of the block minus the address of the jump
2123 // table. This is used for PIC jump tables where gprel32 is not supported.
2124 // e.g.:
2125 // .word LBB123 - LJTI1_2
2126 // If the .set directive avoids relocations, this is emitted as:
2127 // .set L4_5_set_123, LBB123 - LJTI1_2
2128 // .word L4_5_set_123
2129 if (MAI->doesSetDirectiveSuppressReloc()) {
2130 Value = MCSymbolRefExpr::create(GetJTSetSymbol(UID, MBB->getNumber()),
2131 OutContext);
2132 break;
2133 }
2134 Value = MCSymbolRefExpr::create(MBB->getSymbol(), OutContext);
2135 const TargetLowering *TLI = MF->getSubtarget().getTargetLowering();
2136 const MCExpr *Base = TLI->getPICJumpTableRelocBaseExpr(MF, UID, OutContext);
2137 Value = MCBinaryExpr::createSub(Value, Base, OutContext);
2138 break;
2139 }
2140 }
2141
2142 assert(Value && "Unknown entry kind!")((Value && "Unknown entry kind!") ? static_cast<void
> (0) : __assert_fail ("Value && \"Unknown entry kind!\""
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 2142, __PRETTY_FUNCTION__))
;
2143
2144 unsigned EntrySize = MJTI->getEntrySize(getDataLayout());
2145 OutStreamer->emitValue(Value, EntrySize);
2146}
2147
2148/// EmitSpecialLLVMGlobal - Check to see if the specified global is a
2149/// special global used by LLVM. If so, emit it and return true, otherwise
2150/// do nothing and return false.
2151bool AsmPrinter::emitSpecialLLVMGlobal(const GlobalVariable *GV) {
2152 if (GV->getName() == "llvm.used") {
2153 if (MAI->hasNoDeadStrip()) // No need to emit this at all.
2154 emitLLVMUsedList(cast<ConstantArray>(GV->getInitializer()));
2155 return true;
2156 }
2157
2158 // Ignore debug and non-emitted data. This handles llvm.compiler.used.
2159 if (GV->getSection() == "llvm.metadata" ||
2160 GV->hasAvailableExternallyLinkage())
2161 return true;
2162
2163 if (!GV->hasAppendingLinkage()) return false;
2164
2165 assert(GV->hasInitializer() && "Not a special LLVM global!")((GV->hasInitializer() && "Not a special LLVM global!"
) ? static_cast<void> (0) : __assert_fail ("GV->hasInitializer() && \"Not a special LLVM global!\""
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 2165, __PRETTY_FUNCTION__))
;
2166
2167 if (GV->getName() == "llvm.global_ctors") {
2168 emitXXStructorList(GV->getParent()->getDataLayout(), GV->getInitializer(),
2169 /* isCtor */ true);
2170
2171 return true;
2172 }
2173
2174 if (GV->getName() == "llvm.global_dtors") {
2175 emitXXStructorList(GV->getParent()->getDataLayout(), GV->getInitializer(),
2176 /* isCtor */ false);
2177
2178 return true;
2179 }
2180
2181 report_fatal_error("unknown special variable");
2182}
2183
2184/// EmitLLVMUsedList - For targets that define a MAI::UsedDirective, mark each
2185/// global in the specified llvm.used list.
2186void AsmPrinter::emitLLVMUsedList(const ConstantArray *InitList) {
2187 // Should be an array of 'i8*'.
2188 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
2189 const GlobalValue *GV =
2190 dyn_cast<GlobalValue>(InitList->getOperand(i)->stripPointerCasts());
2191 if (GV)
2192 OutStreamer->emitSymbolAttribute(getSymbol(GV), MCSA_NoDeadStrip);
2193 }
2194}
2195
2196void AsmPrinter::preprocessXXStructorList(const DataLayout &DL,
2197 const Constant *List,
2198 SmallVector<Structor, 8> &Structors) {
2199 // Should be an array of '{ i32, void ()*, i8* }' structs. The first value is
2200 // the init priority.
2201 if (!isa<ConstantArray>(List))
2202 return;
2203
2204 // Gather the structors in a form that's convenient for sorting by priority.
2205 for (Value *O : cast<ConstantArray>(List)->operands()) {
2206 auto *CS = cast<ConstantStruct>(O);
2207 if (CS->getOperand(1)->isNullValue())
2208 break; // Found a null terminator, skip the rest.
2209 ConstantInt *Priority = dyn_cast<ConstantInt>(CS->getOperand(0));
2210 if (!Priority)
2211 continue; // Malformed.
2212 Structors.push_back(Structor());
2213 Structor &S = Structors.back();
2214 S.Priority = Priority->getLimitedValue(65535);
2215 S.Func = CS->getOperand(1);
2216 if (!CS->getOperand(2)->isNullValue()) {
2217 if (TM.getTargetTriple().isOSAIX())
2218 llvm::report_fatal_error(
2219 "associated data of XXStructor list is not yet supported on AIX");
2220 S.ComdatKey =
2221 dyn_cast<GlobalValue>(CS->getOperand(2)->stripPointerCasts());
2222 }
2223 }
2224
2225 // Emit the function pointers in the target-specific order
2226 llvm::stable_sort(Structors, [](const Structor &L, const Structor &R) {
2227 return L.Priority < R.Priority;
2228 });
2229}
2230
2231/// EmitXXStructorList - Emit the ctor or dtor list taking into account the init
2232/// priority.
2233void AsmPrinter::emitXXStructorList(const DataLayout &DL, const Constant *List,
2234 bool IsCtor) {
2235 SmallVector<Structor, 8> Structors;
2236 preprocessXXStructorList(DL, List, Structors);
2237 if (Structors.empty())
2238 return;
2239
2240 const Align Align = DL.getPointerPrefAlignment();
2241 for (Structor &S : Structors) {
2242 const TargetLoweringObjectFile &Obj = getObjFileLowering();
2243 const MCSymbol *KeySym = nullptr;
2244 if (GlobalValue *GV = S.ComdatKey) {
2245 if (GV->isDeclarationForLinker())
2246 // If the associated variable is not defined in this module
2247 // (it might be available_externally, or have been an
2248 // available_externally definition that was dropped by the
2249 // EliminateAvailableExternally pass), some other TU
2250 // will provide its dynamic initializer.
2251 continue;
2252
2253 KeySym = getSymbol(GV);
2254 }
2255
2256 MCSection *OutputSection =
2257 (IsCtor ? Obj.getStaticCtorSection(S.Priority, KeySym)
2258 : Obj.getStaticDtorSection(S.Priority, KeySym));
2259 OutStreamer->SwitchSection(OutputSection);
2260 if (OutStreamer->getCurrentSection() != OutStreamer->getPreviousSection())
2261 emitAlignment(Align);
2262 emitXXStructor(DL, S.Func);
2263 }
2264}
2265
2266void AsmPrinter::emitModuleIdents(Module &M) {
2267 if (!MAI->hasIdentDirective())
2268 return;
2269
2270 if (const NamedMDNode *NMD = M.getNamedMetadata("llvm.ident")) {
2271 for (unsigned i = 0, e = NMD->getNumOperands(); i != e; ++i) {
2272 const MDNode *N = NMD->getOperand(i);
2273 assert(N->getNumOperands() == 1 &&((N->getNumOperands() == 1 && "llvm.ident metadata entry can have only one operand"
) ? static_cast<void> (0) : __assert_fail ("N->getNumOperands() == 1 && \"llvm.ident metadata entry can have only one operand\""
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 2274, __PRETTY_FUNCTION__))
2274 "llvm.ident metadata entry can have only one operand")((N->getNumOperands() == 1 && "llvm.ident metadata entry can have only one operand"
) ? static_cast<void> (0) : __assert_fail ("N->getNumOperands() == 1 && \"llvm.ident metadata entry can have only one operand\""
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 2274, __PRETTY_FUNCTION__))
;
2275 const MDString *S = cast<MDString>(N->getOperand(0));
2276 OutStreamer->emitIdent(S->getString());
2277 }
2278 }
2279}
2280
2281void AsmPrinter::emitModuleCommandLines(Module &M) {
2282 MCSection *CommandLine = getObjFileLowering().getSectionForCommandLines();
2283 if (!CommandLine)
2284 return;
2285
2286 const NamedMDNode *NMD = M.getNamedMetadata("llvm.commandline");
2287 if (!NMD || !NMD->getNumOperands())
2288 return;
2289
2290 OutStreamer->PushSection();
2291 OutStreamer->SwitchSection(CommandLine);
2292 OutStreamer->emitZeros(1);
2293 for (unsigned i = 0, e = NMD->getNumOperands(); i != e; ++i) {
2294 const MDNode *N = NMD->getOperand(i);
2295 assert(N->getNumOperands() == 1 &&((N->getNumOperands() == 1 && "llvm.commandline metadata entry can have only one operand"
) ? static_cast<void> (0) : __assert_fail ("N->getNumOperands() == 1 && \"llvm.commandline metadata entry can have only one operand\""
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 2296, __PRETTY_FUNCTION__))
2296 "llvm.commandline metadata entry can have only one operand")((N->getNumOperands() == 1 && "llvm.commandline metadata entry can have only one operand"
) ? static_cast<void> (0) : __assert_fail ("N->getNumOperands() == 1 && \"llvm.commandline metadata entry can have only one operand\""
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 2296, __PRETTY_FUNCTION__))
;
2297 const MDString *S = cast<MDString>(N->getOperand(0));
2298 OutStreamer->emitBytes(S->getString());
2299 OutStreamer->emitZeros(1);
2300 }
2301 OutStreamer->PopSection();
2302}
2303
2304//===--------------------------------------------------------------------===//
2305// Emission and print routines
2306//
2307
2308/// Emit a byte directive and value.
2309///
2310void AsmPrinter::emitInt8(int Value) const { OutStreamer->emitInt8(Value); }
2311
2312/// Emit a short directive and value.
2313void AsmPrinter::emitInt16(int Value) const { OutStreamer->emitInt16(Value); }
2314
2315/// Emit a long directive and value.
2316void AsmPrinter::emitInt32(int Value) const { OutStreamer->emitInt32(Value); }
2317
2318/// Emit a long long directive and value.
2319void AsmPrinter::emitInt64(uint64_t Value) const {
2320 OutStreamer->emitInt64(Value);
2321}
2322
2323/// Emit something like ".long Hi-Lo" where the size in bytes of the directive
2324/// is specified by Size and Hi/Lo specify the labels. This implicitly uses
2325/// .set if it avoids relocations.
2326void AsmPrinter::emitLabelDifference(const MCSymbol *Hi, const MCSymbol *Lo,
2327 unsigned Size) const {
2328 OutStreamer->emitAbsoluteSymbolDiff(Hi, Lo, Size);
2329}
2330
2331/// EmitLabelPlusOffset - Emit something like ".long Label+Offset"
2332/// where the size in bytes of the directive is specified by Size and Label
2333/// specifies the label. This implicitly uses .set if it is available.
2334void AsmPrinter::emitLabelPlusOffset(const MCSymbol *Label, uint64_t Offset,
2335 unsigned Size,
2336 bool IsSectionRelative) const {
2337 if (MAI->needsDwarfSectionOffsetDirective() && IsSectionRelative) {
2338 OutStreamer->EmitCOFFSecRel32(Label, Offset);
2339 if (Size > 4)
2340 OutStreamer->emitZeros(Size - 4);
2341 return;
2342 }
2343
2344 // Emit Label+Offset (or just Label if Offset is zero)
2345 const MCExpr *Expr = MCSymbolRefExpr::create(Label, OutContext);
2346 if (Offset)
2347 Expr = MCBinaryExpr::createAdd(
2348 Expr, MCConstantExpr::create(Offset, OutContext), OutContext);
2349
2350 OutStreamer->emitValue(Expr, Size);
2351}
2352
2353//===----------------------------------------------------------------------===//
2354
2355// EmitAlignment - Emit an alignment directive to the specified power of
2356// two boundary. If a global value is specified, and if that global has
2357// an explicit alignment requested, it will override the alignment request
2358// if required for correctness.
2359void AsmPrinter::emitAlignment(Align Alignment, const GlobalObject *GV) const {
2360 if (GV)
2361 Alignment = getGVAlignment(GV, GV->getParent()->getDataLayout(), Alignment);
2362
2363 if (Alignment == Align(1))
2364 return; // 1-byte aligned: no need to emit alignment.
2365
2366 if (getCurrentSection()->getKind().isText())
2367 OutStreamer->emitCodeAlignment(Alignment.value());
2368 else
2369 OutStreamer->emitValueToAlignment(Alignment.value());
2370}
2371
2372//===----------------------------------------------------------------------===//
2373// Constant emission.
2374//===----------------------------------------------------------------------===//
2375
2376const MCExpr *AsmPrinter::lowerConstant(const Constant *CV) {
2377 MCContext &Ctx = OutContext;
2378
2379 if (CV->isNullValue() || isa<UndefValue>(CV))
2380 return MCConstantExpr::create(0, Ctx);
2381
2382 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV))
2383 return MCConstantExpr::create(CI->getZExtValue(), Ctx);
2384
2385 if (const GlobalValue *GV = dyn_cast<GlobalValue>(CV))
2386 return MCSymbolRefExpr::create(getSymbol(GV), Ctx);
2387
2388 if (const BlockAddress *BA = dyn_cast<BlockAddress>(CV))
2389 return MCSymbolRefExpr::create(GetBlockAddressSymbol(BA), Ctx);
2390
2391 if (const auto *Equiv = dyn_cast<DSOLocalEquivalent>(CV))
2392 return getObjFileLowering().lowerDSOLocalEquivalent(Equiv, TM);
2393
2394 const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV);
2395 if (!CE) {
2396 llvm_unreachable("Unknown constant value to lower!")::llvm::llvm_unreachable_internal("Unknown constant value to lower!"
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 2396)
;
2397 }
2398
2399 switch (CE->getOpcode()) {
2400 case Instruction::AddrSpaceCast: {
2401 const Constant *Op = CE->getOperand(0);
2402 unsigned DstAS = CE->getType()->getPointerAddressSpace();
2403 unsigned SrcAS = Op->getType()->getPointerAddressSpace();
2404 if (TM.isNoopAddrSpaceCast(SrcAS, DstAS))
2405 return lowerConstant(Op);
2406
2407 // Fallthrough to error.
2408 LLVM_FALLTHROUGH[[gnu::fallthrough]];
2409 }
2410 default: {
2411 // If the code isn't optimized, there may be outstanding folding
2412 // opportunities. Attempt to fold the expression using DataLayout as a
2413 // last resort before giving up.
2414 Constant *C = ConstantFoldConstant(CE, getDataLayout());
2415 if (C != CE)
2416 return lowerConstant(C);
2417
2418 // Otherwise report the problem to the user.
2419 std::string S;
2420 raw_string_ostream OS(S);
2421 OS << "Unsupported expression in static initializer: ";
2422 CE->printAsOperand(OS, /*PrintType=*/false,
2423 !MF ? nullptr : MF->getFunction().getParent());
2424 report_fatal_error(OS.str());
2425 }
2426 case Instruction::GetElementPtr: {
2427 // Generate a symbolic expression for the byte address
2428 APInt OffsetAI(getDataLayout().getPointerTypeSizeInBits(CE->getType()), 0);
2429 cast<GEPOperator>(CE)->accumulateConstantOffset(getDataLayout(), OffsetAI);
2430
2431 const MCExpr *Base = lowerConstant(CE->getOperand(0));
2432 if (!OffsetAI)
2433 return Base;
2434
2435 int64_t Offset = OffsetAI.getSExtValue();
2436 return MCBinaryExpr::createAdd(Base, MCConstantExpr::create(Offset, Ctx),
2437 Ctx);
2438 }
2439
2440 case Instruction::Trunc:
2441 // We emit the value and depend on the assembler to truncate the generated
2442 // expression properly. This is important for differences between
2443 // blockaddress labels. Since the two labels are in the same function, it
2444 // is reasonable to treat their delta as a 32-bit value.
2445 LLVM_FALLTHROUGH[[gnu::fallthrough]];
2446 case Instruction::BitCast:
2447 return lowerConstant(CE->getOperand(0));
2448
2449 case Instruction::IntToPtr: {
2450 const DataLayout &DL = getDataLayout();
2451
2452 // Handle casts to pointers by changing them into casts to the appropriate
2453 // integer type. This promotes constant folding and simplifies this code.
2454 Constant *Op = CE->getOperand(0);
2455 Op = ConstantExpr::getIntegerCast(Op, DL.getIntPtrType(CV->getType()),
2456 false/*ZExt*/);
2457 return lowerConstant(Op);
2458 }
2459
2460 case Instruction::PtrToInt: {
2461 const DataLayout &DL = getDataLayout();
2462
2463 // Support only foldable casts to/from pointers that can be eliminated by
2464 // changing the pointer to the appropriately sized integer type.
2465 Constant *Op = CE->getOperand(0);
2466 Type *Ty = CE->getType();
2467
2468 const MCExpr *OpExpr = lowerConstant(Op);
2469
2470 // We can emit the pointer value into this slot if the slot is an
2471 // integer slot equal to the size of the pointer.
2472 //
2473 // If the pointer is larger than the resultant integer, then
2474 // as with Trunc just depend on the assembler to truncate it.
2475 if (DL.getTypeAllocSize(Ty).getFixedSize() <=
2476 DL.getTypeAllocSize(Op->getType()).getFixedSize())
2477 return OpExpr;
2478
2479 // Otherwise the pointer is smaller than the resultant integer, mask off
2480 // the high bits so we are sure to get a proper truncation if the input is
2481 // a constant expr.
2482 unsigned InBits = DL.getTypeAllocSizeInBits(Op->getType());
2483 const MCExpr *MaskExpr = MCConstantExpr::create(~0ULL >> (64-InBits), Ctx);
2484 return MCBinaryExpr::createAnd(OpExpr, MaskExpr, Ctx);
2485 }
2486
2487 case Instruction::Sub: {
2488 GlobalValue *LHSGV;
2489 APInt LHSOffset;
2490 DSOLocalEquivalent *DSOEquiv;
2491 if (IsConstantOffsetFromGlobal(CE->getOperand(0), LHSGV, LHSOffset,
2492 getDataLayout(), &DSOEquiv)) {
2493 GlobalValue *RHSGV;
2494 APInt RHSOffset;
2495 if (IsConstantOffsetFromGlobal(CE->getOperand(1), RHSGV, RHSOffset,
2496 getDataLayout())) {
2497 const MCExpr *RelocExpr =
2498 getObjFileLowering().lowerRelativeReference(LHSGV, RHSGV, TM);
2499 if (!RelocExpr) {
2500 const MCExpr *LHSExpr =
2501 MCSymbolRefExpr::create(getSymbol(LHSGV), Ctx);
2502 if (DSOEquiv &&
2503 getObjFileLowering().supportDSOLocalEquivalentLowering())
2504 LHSExpr =
2505 getObjFileLowering().lowerDSOLocalEquivalent(DSOEquiv, TM);
2506 RelocExpr = MCBinaryExpr::createSub(
2507 LHSExpr, MCSymbolRefExpr::create(getSymbol(RHSGV), Ctx), Ctx);
2508 }
2509 int64_t Addend = (LHSOffset - RHSOffset).getSExtValue();
2510 if (Addend != 0)
2511 RelocExpr = MCBinaryExpr::createAdd(
2512 RelocExpr, MCConstantExpr::create(Addend, Ctx), Ctx);
2513 return RelocExpr;
2514 }
2515 }
2516 }
2517 // else fallthrough
2518 LLVM_FALLTHROUGH[[gnu::fallthrough]];
2519
2520 // The MC library also has a right-shift operator, but it isn't consistently
2521 // signed or unsigned between different targets.
2522 case Instruction::Add:
2523 case Instruction::Mul:
2524 case Instruction::SDiv:
2525 case Instruction::SRem:
2526 case Instruction::Shl:
2527 case Instruction::And:
2528 case Instruction::Or:
2529 case Instruction::Xor: {
2530 const MCExpr *LHS = lowerConstant(CE->getOperand(0));
2531 const MCExpr *RHS = lowerConstant(CE->getOperand(1));
2532 switch (CE->getOpcode()) {
2533 default: llvm_unreachable("Unknown binary operator constant cast expr")::llvm::llvm_unreachable_internal("Unknown binary operator constant cast expr"
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 2533)
;
2534 case Instruction::Add: return MCBinaryExpr::createAdd(LHS, RHS, Ctx);
2535 case Instruction::Sub: return MCBinaryExpr::createSub(LHS, RHS, Ctx);
2536 case Instruction::Mul: return MCBinaryExpr::createMul(LHS, RHS, Ctx);
2537 case Instruction::SDiv: return MCBinaryExpr::createDiv(LHS, RHS, Ctx);
2538 case Instruction::SRem: return MCBinaryExpr::createMod(LHS, RHS, Ctx);
2539 case Instruction::Shl: return MCBinaryExpr::createShl(LHS, RHS, Ctx);
2540 case Instruction::And: return MCBinaryExpr::createAnd(LHS, RHS, Ctx);
2541 case Instruction::Or: return MCBinaryExpr::createOr (LHS, RHS, Ctx);
2542 case Instruction::Xor: return MCBinaryExpr::createXor(LHS, RHS, Ctx);
2543 }
2544 }
2545 }
2546}
2547
2548static void emitGlobalConstantImpl(const DataLayout &DL, const Constant *C,
2549 AsmPrinter &AP,
2550 const Constant *BaseCV = nullptr,
2551 uint64_t Offset = 0);
2552
2553static void emitGlobalConstantFP(const ConstantFP *CFP, AsmPrinter &AP);
2554static void emitGlobalConstantFP(APFloat APF, Type *ET, AsmPrinter &AP);
2555
2556/// isRepeatedByteSequence - Determine whether the given value is
2557/// composed of a repeated sequence of identical bytes and return the
2558/// byte value. If it is not a repeated sequence, return -1.
2559static int isRepeatedByteSequence(const ConstantDataSequential *V) {
2560 StringRef Data = V->getRawDataValues();
2561 assert(!Data.empty() && "Empty aggregates should be CAZ node")((!Data.empty() && "Empty aggregates should be CAZ node"
) ? static_cast<void> (0) : __assert_fail ("!Data.empty() && \"Empty aggregates should be CAZ node\""
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 2561, __PRETTY_FUNCTION__))
;
2562 char C = Data[0];
2563 for (unsigned i = 1, e = Data.size(); i != e; ++i)
2564 if (Data[i] != C) return -1;
2565 return static_cast<uint8_t>(C); // Ensure 255 is not returned as -1.
2566}
2567
2568/// isRepeatedByteSequence - Determine whether the given value is
2569/// composed of a repeated sequence of identical bytes and return the
2570/// byte value. If it is not a repeated sequence, return -1.
2571static int isRepeatedByteSequence(const Value *V, const DataLayout &DL) {
2572 if (const ConstantInt *CI = dyn_cast<ConstantInt>(V)) {
2573 uint64_t Size = DL.getTypeAllocSizeInBits(V->getType());
2574 assert(Size % 8 == 0)((Size % 8 == 0) ? static_cast<void> (0) : __assert_fail
("Size % 8 == 0", "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 2574, __PRETTY_FUNCTION__))
;
2575
2576 // Extend the element to take zero padding into account.
2577 APInt Value = CI->getValue().zextOrSelf(Size);
2578 if (!Value.isSplat(8))
2579 return -1;
2580
2581 return Value.zextOrTrunc(8).getZExtValue();
2582 }
2583 if (const ConstantArray *CA = dyn_cast<ConstantArray>(V)) {
2584 // Make sure all array elements are sequences of the same repeated
2585 // byte.
2586 assert(CA->getNumOperands() != 0 && "Should be a CAZ")((CA->getNumOperands() != 0 && "Should be a CAZ") ?
static_cast<void> (0) : __assert_fail ("CA->getNumOperands() != 0 && \"Should be a CAZ\""
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 2586, __PRETTY_FUNCTION__))
;
2587 Constant *Op0 = CA->getOperand(0);
2588 int Byte = isRepeatedByteSequence(Op0, DL);
2589 if (Byte == -1)
2590 return -1;
2591
2592 // All array elements must be equal.
2593 for (unsigned i = 1, e = CA->getNumOperands(); i != e; ++i)
2594 if (CA->getOperand(i) != Op0)
2595 return -1;
2596 return Byte;
2597 }
2598
2599 if (const ConstantDataSequential *CDS = dyn_cast<ConstantDataSequential>(V))
2600 return isRepeatedByteSequence(CDS);
2601
2602 return -1;
2603}
2604
2605static void emitGlobalConstantDataSequential(const DataLayout &DL,
2606 const ConstantDataSequential *CDS,
2607 AsmPrinter &AP) {
2608 // See if we can aggregate this into a .fill, if so, emit it as such.
2609 int Value = isRepeatedByteSequence(CDS, DL);
2610 if (Value != -1) {
2611 uint64_t Bytes = DL.getTypeAllocSize(CDS->getType());
2612 // Don't emit a 1-byte object as a .fill.
2613 if (Bytes > 1)
2614 return AP.OutStreamer->emitFill(Bytes, Value);
2615 }
2616
2617 // If this can be emitted with .ascii/.asciz, emit it as such.
2618 if (CDS->isString())
2619 return AP.OutStreamer->emitBytes(CDS->getAsString());
2620
2621 // Otherwise, emit the values in successive locations.
2622 unsigned ElementByteSize = CDS->getElementByteSize();
2623 if (isa<IntegerType>(CDS->getElementType())) {
2624 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
2625 if (AP.isVerbose())
2626 AP.OutStreamer->GetCommentOS() << format("0x%" PRIx64"l" "x" "\n",
2627 CDS->getElementAsInteger(i));
2628 AP.OutStreamer->emitIntValue(CDS->getElementAsInteger(i),
2629 ElementByteSize);
2630 }
2631 } else {
2632 Type *ET = CDS->getElementType();
2633 for (unsigned I = 0, E = CDS->getNumElements(); I != E; ++I)
2634 emitGlobalConstantFP(CDS->getElementAsAPFloat(I), ET, AP);
2635 }
2636
2637 unsigned Size = DL.getTypeAllocSize(CDS->getType());
2638 unsigned EmittedSize =
2639 DL.getTypeAllocSize(CDS->getElementType()) * CDS->getNumElements();
2640 assert(EmittedSize <= Size && "Size cannot be less than EmittedSize!")((EmittedSize <= Size && "Size cannot be less than EmittedSize!"
) ? static_cast<void> (0) : __assert_fail ("EmittedSize <= Size && \"Size cannot be less than EmittedSize!\""
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 2640, __PRETTY_FUNCTION__))
;
2641 if (unsigned Padding = Size - EmittedSize)
2642 AP.OutStreamer->emitZeros(Padding);
2643}
2644
2645static void emitGlobalConstantArray(const DataLayout &DL,
2646 const ConstantArray *CA, AsmPrinter &AP,
2647 const Constant *BaseCV, uint64_t Offset) {
2648 // See if we can aggregate some values. Make sure it can be
2649 // represented as a series of bytes of the constant value.
2650 int Value = isRepeatedByteSequence(CA, DL);
2651
2652 if (Value != -1) {
2653 uint64_t Bytes = DL.getTypeAllocSize(CA->getType());
2654 AP.OutStreamer->emitFill(Bytes, Value);
2655 }
2656 else {
2657 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i) {
2658 emitGlobalConstantImpl(DL, CA->getOperand(i), AP, BaseCV, Offset);
2659 Offset += DL.getTypeAllocSize(CA->getOperand(i)->getType());
2660 }
2661 }
2662}
2663
2664static void emitGlobalConstantVector(const DataLayout &DL,
2665 const ConstantVector *CV, AsmPrinter &AP) {
2666 for (unsigned i = 0, e = CV->getType()->getNumElements(); i != e; ++i)
2667 emitGlobalConstantImpl(DL, CV->getOperand(i), AP);
2668
2669 unsigned Size = DL.getTypeAllocSize(CV->getType());
2670 unsigned EmittedSize = DL.getTypeAllocSize(CV->getType()->getElementType()) *
2671 CV->getType()->getNumElements();
2672 if (unsigned Padding = Size - EmittedSize)
2673 AP.OutStreamer->emitZeros(Padding);
2674}
2675
2676static void emitGlobalConstantStruct(const DataLayout &DL,
2677 const ConstantStruct *CS, AsmPrinter &AP,
2678 const Constant *BaseCV, uint64_t Offset) {
2679 // Print the fields in successive locations. Pad to align if needed!
2680 unsigned Size = DL.getTypeAllocSize(CS->getType());
2681 const StructLayout *Layout = DL.getStructLayout(CS->getType());
2682 uint64_t SizeSoFar = 0;
2683 for (unsigned i = 0, e = CS->getNumOperands(); i != e; ++i) {
2684 const Constant *Field = CS->getOperand(i);
2685
2686 // Print the actual field value.
2687 emitGlobalConstantImpl(DL, Field, AP, BaseCV, Offset + SizeSoFar);
2688
2689 // Check if padding is needed and insert one or more 0s.
2690 uint64_t FieldSize = DL.getTypeAllocSize(Field->getType());
2691 uint64_t PadSize = ((i == e-1 ? Size : Layout->getElementOffset(i+1))
2692 - Layout->getElementOffset(i)) - FieldSize;
2693 SizeSoFar += FieldSize + PadSize;
2694
2695 // Insert padding - this may include padding to increase the size of the
2696 // current field up to the ABI size (if the struct is not packed) as well
2697 // as padding to ensure that the next field starts at the right offset.
2698 AP.OutStreamer->emitZeros(PadSize);
2699 }
2700 assert(SizeSoFar == Layout->getSizeInBytes() &&((SizeSoFar == Layout->getSizeInBytes() && "Layout of constant struct may be incorrect!"
) ? static_cast<void> (0) : __assert_fail ("SizeSoFar == Layout->getSizeInBytes() && \"Layout of constant struct may be incorrect!\""
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 2701, __PRETTY_FUNCTION__))
2701 "Layout of constant struct may be incorrect!")((SizeSoFar == Layout->getSizeInBytes() && "Layout of constant struct may be incorrect!"
) ? static_cast<void> (0) : __assert_fail ("SizeSoFar == Layout->getSizeInBytes() && \"Layout of constant struct may be incorrect!\""
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 2701, __PRETTY_FUNCTION__))
;
2702}
2703
2704static void emitGlobalConstantFP(APFloat APF, Type *ET, AsmPrinter &AP) {
2705 assert(ET && "Unknown float type")((ET && "Unknown float type") ? static_cast<void>
(0) : __assert_fail ("ET && \"Unknown float type\"",
"/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 2705, __PRETTY_FUNCTION__))
;
2706 APInt API = APF.bitcastToAPInt();
2707
2708 // First print a comment with what we think the original floating-point value
2709 // should have been.
2710 if (AP.isVerbose()) {
2711 SmallString<8> StrVal;
2712 APF.toString(StrVal);
2713 ET->print(AP.OutStreamer->GetCommentOS());
2714 AP.OutStreamer->GetCommentOS() << ' ' << StrVal << '\n';
2715 }
2716
2717 // Now iterate through the APInt chunks, emitting them in endian-correct
2718 // order, possibly with a smaller chunk at beginning/end (e.g. for x87 80-bit
2719 // floats).
2720 unsigned NumBytes = API.getBitWidth() / 8;
2721 unsigned TrailingBytes = NumBytes % sizeof(uint64_t);
2722 const uint64_t *p = API.getRawData();
2723
2724 // PPC's long double has odd notions of endianness compared to how LLVM
2725 // handles it: p[0] goes first for *big* endian on PPC.
2726 if (AP.getDataLayout().isBigEndian() && !ET->isPPC_FP128Ty()) {
2727 int Chunk = API.getNumWords() - 1;
2728
2729 if (TrailingBytes)
2730 AP.OutStreamer->emitIntValueInHexWithPadding(p[Chunk--], TrailingBytes);
2731
2732 for (; Chunk >= 0; --Chunk)
2733 AP.OutStreamer->emitIntValueInHexWithPadding(p[Chunk], sizeof(uint64_t));
2734 } else {
2735 unsigned Chunk;
2736 for (Chunk = 0; Chunk < NumBytes / sizeof(uint64_t); ++Chunk)
2737 AP.OutStreamer->emitIntValueInHexWithPadding(p[Chunk], sizeof(uint64_t));
2738
2739 if (TrailingBytes)
2740 AP.OutStreamer->emitIntValueInHexWithPadding(p[Chunk], TrailingBytes);
2741 }
2742
2743 // Emit the tail padding for the long double.
2744 const DataLayout &DL = AP.getDataLayout();
2745 AP.OutStreamer->emitZeros(DL.getTypeAllocSize(ET) - DL.getTypeStoreSize(ET));
2746}
2747
2748static void emitGlobalConstantFP(const ConstantFP *CFP, AsmPrinter &AP) {
2749 emitGlobalConstantFP(CFP->getValueAPF(), CFP->getType(), AP);
2750}
2751
2752static void emitGlobalConstantLargeInt(const ConstantInt *CI, AsmPrinter &AP) {
2753 const DataLayout &DL = AP.getDataLayout();
2754 unsigned BitWidth = CI->getBitWidth();
2755
2756 // Copy the value as we may massage the layout for constants whose bit width
2757 // is not a multiple of 64-bits.
2758 APInt Realigned(CI->getValue());
2759 uint64_t ExtraBits = 0;
2760 unsigned ExtraBitsSize = BitWidth & 63;
2761
2762 if (ExtraBitsSize) {
2763 // The bit width of the data is not a multiple of 64-bits.
2764 // The extra bits are expected to be at the end of the chunk of the memory.
2765 // Little endian:
2766 // * Nothing to be done, just record the extra bits to emit.
2767 // Big endian:
2768 // * Record the extra bits to emit.
2769 // * Realign the raw data to emit the chunks of 64-bits.
2770 if (DL.isBigEndian()) {
2771 // Basically the structure of the raw data is a chunk of 64-bits cells:
2772 // 0 1 BitWidth / 64
2773 // [chunk1][chunk2] ... [chunkN].
2774 // The most significant chunk is chunkN and it should be emitted first.
2775 // However, due to the alignment issue chunkN contains useless bits.
2776 // Realign the chunks so that they contain only useful information:
2777 // ExtraBits 0 1 (BitWidth / 64) - 1
2778 // chu[nk1 chu][nk2 chu] ... [nkN-1 chunkN]
2779 ExtraBitsSize = alignTo(ExtraBitsSize, 8);
2780 ExtraBits = Realigned.getRawData()[0] &
2781 (((uint64_t)-1) >> (64 - ExtraBitsSize));
2782 Realigned.lshrInPlace(ExtraBitsSize);
2783 } else
2784 ExtraBits = Realigned.getRawData()[BitWidth / 64];
2785 }
2786
2787 // We don't expect assemblers to support integer data directives
2788 // for more than 64 bits, so we emit the data in at most 64-bit
2789 // quantities at a time.
2790 const uint64_t *RawData = Realigned.getRawData();
2791 for (unsigned i = 0, e = BitWidth / 64; i != e; ++i) {
2792 uint64_t Val = DL.isBigEndian() ? RawData[e - i - 1] : RawData[i];
2793 AP.OutStreamer->emitIntValue(Val, 8);
2794 }
2795
2796 if (ExtraBitsSize) {
2797 // Emit the extra bits after the 64-bits chunks.
2798
2799 // Emit a directive that fills the expected size.
2800 uint64_t Size = AP.getDataLayout().getTypeStoreSize(CI->getType());
2801 Size -= (BitWidth / 64) * 8;
2802 assert(Size && Size * 8 >= ExtraBitsSize &&((Size && Size * 8 >= ExtraBitsSize && (ExtraBits
& (((uint64_t)-1) >> (64 - ExtraBitsSize))) == ExtraBits
&& "Directive too small for extra bits.") ? static_cast
<void> (0) : __assert_fail ("Size && Size * 8 >= ExtraBitsSize && (ExtraBits & (((uint64_t)-1) >> (64 - ExtraBitsSize))) == ExtraBits && \"Directive too small for extra bits.\""
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 2804, __PRETTY_FUNCTION__))
2803 (ExtraBits & (((uint64_t)-1) >> (64 - ExtraBitsSize)))((Size && Size * 8 >= ExtraBitsSize && (ExtraBits
& (((uint64_t)-1) >> (64 - ExtraBitsSize))) == ExtraBits
&& "Directive too small for extra bits.") ? static_cast
<void> (0) : __assert_fail ("Size && Size * 8 >= ExtraBitsSize && (ExtraBits & (((uint64_t)-1) >> (64 - ExtraBitsSize))) == ExtraBits && \"Directive too small for extra bits.\""
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 2804, __PRETTY_FUNCTION__))
2804 == ExtraBits && "Directive too small for extra bits.")((Size && Size * 8 >= ExtraBitsSize && (ExtraBits
& (((uint64_t)-1) >> (64 - ExtraBitsSize))) == ExtraBits
&& "Directive too small for extra bits.") ? static_cast
<void> (0) : __assert_fail ("Size && Size * 8 >= ExtraBitsSize && (ExtraBits & (((uint64_t)-1) >> (64 - ExtraBitsSize))) == ExtraBits && \"Directive too small for extra bits.\""
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 2804, __PRETTY_FUNCTION__))
;
2805 AP.OutStreamer->emitIntValue(ExtraBits, Size);
2806 }
2807}
2808
2809/// Transform a not absolute MCExpr containing a reference to a GOT
2810/// equivalent global, by a target specific GOT pc relative access to the
2811/// final symbol.
2812static void handleIndirectSymViaGOTPCRel(AsmPrinter &AP, const MCExpr **ME,
2813 const Constant *BaseCst,
2814 uint64_t Offset) {
2815 // The global @foo below illustrates a global that uses a got equivalent.
2816 //
2817 // @bar = global i32 42
2818 // @gotequiv = private unnamed_addr constant i32* @bar
2819 // @foo = i32 trunc (i64 sub (i64 ptrtoint (i32** @gotequiv to i64),
2820 // i64 ptrtoint (i32* @foo to i64))
2821 // to i32)
2822 //
2823 // The cstexpr in @foo is converted into the MCExpr `ME`, where we actually
2824 // check whether @foo is suitable to use a GOTPCREL. `ME` is usually in the
2825 // form:
2826 //
2827 // foo = cstexpr, where
2828 // cstexpr := <gotequiv> - "." + <cst>
2829 // cstexpr := <gotequiv> - (<foo> - <offset from @foo base>) + <cst>
2830 //
2831 // After canonicalization by evaluateAsRelocatable `ME` turns into:
2832 //
2833 // cstexpr := <gotequiv> - <foo> + gotpcrelcst, where
2834 // gotpcrelcst := <offset from @foo base> + <cst>
2835 MCValue MV;
2836 if (!(*ME)->evaluateAsRelocatable(MV, nullptr, nullptr) || MV.isAbsolute())
2837 return;
2838 const MCSymbolRefExpr *SymA = MV.getSymA();
2839 if (!SymA)
2840 return;
2841
2842 // Check that GOT equivalent symbol is cached.
2843 const MCSymbol *GOTEquivSym = &SymA->getSymbol();
2844 if (!AP.GlobalGOTEquivs.count(GOTEquivSym))
2845 return;
2846
2847 const GlobalValue *BaseGV = dyn_cast_or_null<GlobalValue>(BaseCst);
2848 if (!BaseGV)
2849 return;
2850
2851 // Check for a valid base symbol
2852 const MCSymbol *BaseSym = AP.getSymbol(BaseGV);
2853 const MCSymbolRefExpr *SymB = MV.getSymB();
2854
2855 if (!SymB || BaseSym != &SymB->getSymbol())
2856 return;
2857
2858 // Make sure to match:
2859 //
2860 // gotpcrelcst := <offset from @foo base> + <cst>
2861 //
2862 // If gotpcrelcst is positive it means that we can safely fold the pc rel
2863 // displacement into the GOTPCREL. We can also can have an extra offset <cst>
2864 // if the target knows how to encode it.
2865 int64_t GOTPCRelCst = Offset + MV.getConstant();
2866 if (GOTPCRelCst < 0)
2867 return;
2868 if (!AP.getObjFileLowering().supportGOTPCRelWithOffset() && GOTPCRelCst != 0)
2869 return;
2870
2871 // Emit the GOT PC relative to replace the got equivalent global, i.e.:
2872 //
2873 // bar:
2874 // .long 42
2875 // gotequiv:
2876 // .quad bar
2877 // foo:
2878 // .long gotequiv - "." + <cst>
2879 //
2880 // is replaced by the target specific equivalent to:
2881 //
2882 // bar:
2883 // .long 42
2884 // foo:
2885 // .long bar@GOTPCREL+<gotpcrelcst>
2886 AsmPrinter::GOTEquivUsePair Result = AP.GlobalGOTEquivs[GOTEquivSym];
2887 const GlobalVariable *GV = Result.first;
2888 int NumUses = (int)Result.second;
2889 const GlobalValue *FinalGV = dyn_cast<GlobalValue>(GV->getOperand(0));
2890 const MCSymbol *FinalSym = AP.getSymbol(FinalGV);
2891 *ME = AP.getObjFileLowering().getIndirectSymViaGOTPCRel(
2892 FinalGV, FinalSym, MV, Offset, AP.MMI, *AP.OutStreamer);
2893
2894 // Update GOT equivalent usage information
2895 --NumUses;
2896 if (NumUses >= 0)
2897 AP.GlobalGOTEquivs[GOTEquivSym] = std::make_pair(GV, NumUses);
2898}
2899
2900static void emitGlobalConstantImpl(const DataLayout &DL, const Constant *CV,
2901 AsmPrinter &AP, const Constant *BaseCV,
2902 uint64_t Offset) {
2903 uint64_t Size = DL.getTypeAllocSize(CV->getType());
2904
2905 // Globals with sub-elements such as combinations of arrays and structs
2906 // are handled recursively by emitGlobalConstantImpl. Keep track of the
2907 // constant symbol base and the current position with BaseCV and Offset.
2908 if (!BaseCV && CV->hasOneUse())
2909 BaseCV = dyn_cast<Constant>(CV->user_back());
2910
2911 if (isa<ConstantAggregateZero>(CV) || isa<UndefValue>(CV))
2912 return AP.OutStreamer->emitZeros(Size);
2913
2914 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
2915 const uint64_t StoreSize = DL.getTypeStoreSize(CV->getType());
2916
2917 if (StoreSize <= 8) {
2918 if (AP.isVerbose())
2919 AP.OutStreamer->GetCommentOS() << format("0x%" PRIx64"l" "x" "\n",
2920 CI->getZExtValue());
2921 AP.OutStreamer->emitIntValue(CI->getZExtValue(), StoreSize);
2922 } else {
2923 emitGlobalConstantLargeInt(CI, AP);
2924 }
2925
2926 // Emit tail padding if needed
2927 if (Size != StoreSize)
2928 AP.OutStreamer->emitZeros(Size - StoreSize);
2929
2930 return;
2931 }
2932
2933 if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV))
2934 return emitGlobalConstantFP(CFP, AP);
2935
2936 if (isa<ConstantPointerNull>(CV)) {
2937 AP.OutStreamer->emitIntValue(0, Size);
2938 return;
2939 }
2940
2941 if (const ConstantDataSequential *CDS = dyn_cast<ConstantDataSequential>(CV))
2942 return emitGlobalConstantDataSequential(DL, CDS, AP);
2943
2944 if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV))
2945 return emitGlobalConstantArray(DL, CVA, AP, BaseCV, Offset);
2946
2947 if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV))
2948 return emitGlobalConstantStruct(DL, CVS, AP, BaseCV, Offset);
2949
2950 if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV)) {
2951 // Look through bitcasts, which might not be able to be MCExpr'ized (e.g. of
2952 // vectors).
2953 if (CE->getOpcode() == Instruction::BitCast)
2954 return emitGlobalConstantImpl(DL, CE->getOperand(0), AP);
2955
2956 if (Size > 8) {
2957 // If the constant expression's size is greater than 64-bits, then we have
2958 // to emit the value in chunks. Try to constant fold the value and emit it
2959 // that way.
2960 Constant *New = ConstantFoldConstant(CE, DL);
2961 if (New != CE)
2962 return emitGlobalConstantImpl(DL, New, AP);
2963 }
2964 }
2965
2966 if (const ConstantVector *V = dyn_cast<ConstantVector>(CV))
2967 return emitGlobalConstantVector(DL, V, AP);
2968
2969 // Otherwise, it must be a ConstantExpr. Lower it to an MCExpr, then emit it
2970 // thread the streamer with EmitValue.
2971 const MCExpr *ME = AP.lowerConstant(CV);
2972
2973 // Since lowerConstant already folded and got rid of all IR pointer and
2974 // integer casts, detect GOT equivalent accesses by looking into the MCExpr
2975 // directly.
2976 if (AP.getObjFileLowering().supportIndirectSymViaGOTPCRel())
2977 handleIndirectSymViaGOTPCRel(AP, &ME, BaseCV, Offset);
2978
2979 AP.OutStreamer->emitValue(ME, Size);
2980}
2981
2982/// EmitGlobalConstant - Print a general LLVM constant to the .s file.
2983void AsmPrinter::emitGlobalConstant(const DataLayout &DL, const Constant *CV) {
2984 uint64_t Size = DL.getTypeAllocSize(CV->getType());
2985 if (Size)
2986 emitGlobalConstantImpl(DL, CV, *this);
2987 else if (MAI->hasSubsectionsViaSymbols()) {
2988 // If the global has zero size, emit a single byte so that two labels don't
2989 // look like they are at the same location.
2990 OutStreamer->emitIntValue(0, 1);
2991 }
2992}
2993
2994void AsmPrinter::emitMachineConstantPoolValue(MachineConstantPoolValue *MCPV) {
2995 // Target doesn't support this yet!
2996 llvm_unreachable("Target does not support EmitMachineConstantPoolValue")::llvm::llvm_unreachable_internal("Target does not support EmitMachineConstantPoolValue"
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 2996)
;
2997}
2998
2999void AsmPrinter::printOffset(int64_t Offset, raw_ostream &OS) const {
3000 if (Offset > 0)
3001 OS << '+' << Offset;
3002 else if (Offset < 0)
3003 OS << Offset;
3004}
3005
3006void AsmPrinter::emitNops(unsigned N) {
3007 MCInst Nop = MF->getSubtarget().getInstrInfo()->getNop();
3008 for (; N; --N)
3009 EmitToStreamer(*OutStreamer, Nop);
3010}
3011
3012//===----------------------------------------------------------------------===//
3013// Symbol Lowering Routines.
3014//===----------------------------------------------------------------------===//
3015
3016MCSymbol *AsmPrinter::createTempSymbol(const Twine &Name) const {
3017 return OutContext.createTempSymbol(Name, true);
3018}
3019
3020MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BlockAddress *BA) const {
3021 return MMI->getAddrLabelSymbol(BA->getBasicBlock());
3022}
3023
3024MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BasicBlock *BB) const {
3025 return MMI->getAddrLabelSymbol(BB);
3026}
3027
3028/// GetCPISymbol - Return the symbol for the specified constant pool entry.
3029MCSymbol *AsmPrinter::GetCPISymbol(unsigned CPID) const {
3030 if (getSubtargetInfo().getTargetTriple().isWindowsMSVCEnvironment()) {
3031 const MachineConstantPoolEntry &CPE =
3032 MF->getConstantPool()->getConstants()[CPID];
3033 if (!CPE.isMachineConstantPoolEntry()) {
3034 const DataLayout &DL = MF->getDataLayout();
3035 SectionKind Kind = CPE.getSectionKind(&DL);
3036 const Constant *C = CPE.Val.ConstVal;
3037 Align Alignment = CPE.Alignment;
3038 if (const MCSectionCOFF *S = dyn_cast<MCSectionCOFF>(
3039 getObjFileLowering().getSectionForConstant(DL, Kind, C,
3040 Alignment))) {
3041 if (MCSymbol *Sym = S->getCOMDATSymbol()) {
3042 if (Sym->isUndefined())
3043 OutStreamer->emitSymbolAttribute(Sym, MCSA_Global);
3044 return Sym;
3045 }
3046 }
3047 }
3048 }
3049
3050 const DataLayout &DL = getDataLayout();
3051 return OutContext.getOrCreateSymbol(Twine(DL.getPrivateGlobalPrefix()) +
3052 "CPI" + Twine(getFunctionNumber()) + "_" +
3053 Twine(CPID));
3054}
3055
3056/// GetJTISymbol - Return the symbol for the specified jump table entry.
3057MCSymbol *AsmPrinter::GetJTISymbol(unsigned JTID, bool isLinkerPrivate) const {
3058 return MF->getJTISymbol(JTID, OutContext, isLinkerPrivate);
3059}
3060
3061/// GetJTSetSymbol - Return the symbol for the specified jump table .set
3062/// FIXME: privatize to AsmPrinter.
3063MCSymbol *AsmPrinter::GetJTSetSymbol(unsigned UID, unsigned MBBID) const {
3064 const DataLayout &DL = getDataLayout();
3065 return OutContext.getOrCreateSymbol(Twine(DL.getPrivateGlobalPrefix()) +
3066 Twine(getFunctionNumber()) + "_" +
3067 Twine(UID) + "_set_" + Twine(MBBID));
3068}
3069
3070MCSymbol *AsmPrinter::getSymbolWithGlobalValueBase(const GlobalValue *GV,
3071 StringRef Suffix) const {
3072 return getObjFileLowering().getSymbolWithGlobalValueBase(GV, Suffix, TM);
3073}
3074
3075/// Return the MCSymbol for the specified ExternalSymbol.
3076MCSymbol *AsmPrinter::GetExternalSymbolSymbol(StringRef Sym) const {
3077 SmallString<60> NameStr;
3078 Mangler::getNameWithPrefix(NameStr, Sym, getDataLayout());
3079 return OutContext.getOrCreateSymbol(NameStr);
3080}
3081
3082/// PrintParentLoopComment - Print comments about parent loops of this one.
3083static void PrintParentLoopComment(raw_ostream &OS, const MachineLoop *Loop,
3084 unsigned FunctionNumber) {
3085 if (!Loop) return;
3086 PrintParentLoopComment(OS, Loop->getParentLoop(), FunctionNumber);
3087 OS.indent(Loop->getLoopDepth()*2)
3088 << "Parent Loop BB" << FunctionNumber << "_"
3089 << Loop->getHeader()->getNumber()
3090 << " Depth=" << Loop->getLoopDepth() << '\n';
3091}
3092
3093/// PrintChildLoopComment - Print comments about child loops within
3094/// the loop for this basic block, with nesting.
3095static void PrintChildLoopComment(raw_ostream &OS, const MachineLoop *Loop,
3096 unsigned FunctionNumber) {
3097 // Add child loop information
3098 for (const MachineLoop *CL : *Loop) {
3099 OS.indent(CL->getLoopDepth()*2)
3100 << "Child Loop BB" << FunctionNumber << "_"
3101 << CL->getHeader()->getNumber() << " Depth " << CL->getLoopDepth()
3102 << '\n';
3103 PrintChildLoopComment(OS, CL, FunctionNumber);
3104 }
3105}
3106
3107/// emitBasicBlockLoopComments - Pretty-print comments for basic blocks.
3108static void emitBasicBlockLoopComments(const MachineBasicBlock &MBB,
3109 const MachineLoopInfo *LI,
3110 const AsmPrinter &AP) {
3111 // Add loop depth information
3112 const MachineLoop *Loop = LI->getLoopFor(&MBB);
3113 if (!Loop) return;
3114
3115 MachineBasicBlock *Header = Loop->getHeader();
3116 assert(Header && "No header for loop")((Header && "No header for loop") ? static_cast<void
> (0) : __assert_fail ("Header && \"No header for loop\""
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 3116, __PRETTY_FUNCTION__))
;
3117
3118 // If this block is not a loop header, just print out what is the loop header
3119 // and return.
3120 if (Header != &MBB) {
3121 AP.OutStreamer->AddComment(" in Loop: Header=BB" +
3122 Twine(AP.getFunctionNumber())+"_" +
3123 Twine(Loop->getHeader()->getNumber())+
3124 " Depth="+Twine(Loop->getLoopDepth()));
3125 return;
3126 }
3127
3128 // Otherwise, it is a loop header. Print out information about child and
3129 // parent loops.
3130 raw_ostream &OS = AP.OutStreamer->GetCommentOS();
3131
3132 PrintParentLoopComment(OS, Loop->getParentLoop(), AP.getFunctionNumber());
3133
3134 OS << "=>";
3135 OS.indent(Loop->getLoopDepth()*2-2);
3136
3137 OS << "This ";
3138 if (Loop->isInnermost())
3139 OS << "Inner ";
3140 OS << "Loop Header: Depth=" + Twine(Loop->getLoopDepth()) << '\n';
3141
3142 PrintChildLoopComment(OS, Loop, AP.getFunctionNumber());
3143}
3144
3145/// emitBasicBlockStart - This method prints the label for the specified
3146/// MachineBasicBlock, an alignment (if present) and a comment describing
3147/// it if appropriate.
3148void AsmPrinter::emitBasicBlockStart(const MachineBasicBlock &MBB) {
3149 // End the previous funclet and start a new one.
3150 if (MBB.isEHFuncletEntry()) {
3151 for (const HandlerInfo &HI : Handlers) {
3152 HI.Handler->endFunclet();
3153 HI.Handler->beginFunclet(MBB);
3154 }
3155 }
3156
3157 // Emit an alignment directive for this block, if needed.
3158 const Align Alignment = MBB.getAlignment();
3159 if (Alignment != Align(1))
3160 emitAlignment(Alignment);
3161
3162 // Switch to a new section if this basic block must begin a section. The
3163 // entry block is always placed in the function section and is handled
3164 // separately.
3165 if (MBB.isBeginSection() && !MBB.isEntryBlock()) {
3166 OutStreamer->SwitchSection(
3167 getObjFileLowering().getSectionForMachineBasicBlock(MF->getFunction(),
3168 MBB, TM));
3169 CurrentSectionBeginSym = MBB.getSymbol();
3170 }
3171
3172 // If the block has its address taken, emit any labels that were used to
3173 // reference the block. It is possible that there is more than one label
3174 // here, because multiple LLVM BB's may have been RAUW'd to this block after
3175 // the references were generated.
3176 if (MBB.hasAddressTaken()) {
3177 const BasicBlock *BB = MBB.getBasicBlock();
3178 if (isVerbose())
3179 OutStreamer->AddComment("Block address taken");
3180
3181 // MBBs can have their address taken as part of CodeGen without having
3182 // their corresponding BB's address taken in IR
3183 if (BB->hasAddressTaken())
3184 for (MCSymbol *Sym : MMI->getAddrLabelSymbolToEmit(BB))
3185 OutStreamer->emitLabel(Sym);
3186 }
3187
3188 // Print some verbose block comments.
3189 if (isVerbose()) {
3190 if (const BasicBlock *BB = MBB.getBasicBlock()) {
3191 if (BB->hasName()) {
3192 BB->printAsOperand(OutStreamer->GetCommentOS(),
3193 /*PrintType=*/false, BB->getModule());
3194 OutStreamer->GetCommentOS() << '\n';
3195 }
3196 }
3197
3198 assert(MLI != nullptr && "MachineLoopInfo should has been computed")((MLI != nullptr && "MachineLoopInfo should has been computed"
) ? static_cast<void> (0) : __assert_fail ("MLI != nullptr && \"MachineLoopInfo should has been computed\""
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 3198, __PRETTY_FUNCTION__))
;
3199 emitBasicBlockLoopComments(MBB, MLI, *this);
3200 }
3201
3202 // Print the main label for the block.
3203 if (shouldEmitLabelForBasicBlock(MBB)) {
3204 if (isVerbose() && MBB.hasLabelMustBeEmitted())
3205 OutStreamer->AddComment("Label of block must be emitted");
3206 OutStreamer->emitLabel(MBB.getSymbol());
3207 } else {
3208 if (isVerbose()) {
3209 // NOTE: Want this comment at start of line, don't emit with AddComment.
3210 OutStreamer->emitRawComment(" %bb." + Twine(MBB.getNumber()) + ":",
3211 false);
3212 }
3213 }
3214
3215 if (MBB.isEHCatchretTarget() &&
3216 MAI->getExceptionHandlingType() == ExceptionHandling::WinEH) {
3217 OutStreamer->emitLabel(MBB.getEHCatchretSymbol());
3218 }
3219
3220 // With BB sections, each basic block must handle CFI information on its own
3221 // if it begins a section (Entry block is handled separately by
3222 // AsmPrinterHandler::beginFunction).
3223 if (MBB.isBeginSection() && !MBB.isEntryBlock())
3224 for (const HandlerInfo &HI : Handlers)
3225 HI.Handler->beginBasicBlock(MBB);
3226}
3227
3228void AsmPrinter::emitBasicBlockEnd(const MachineBasicBlock &MBB) {
3229 // Check if CFI information needs to be updated for this MBB with basic block
3230 // sections.
3231 if (MBB.isEndSection())
3232 for (const HandlerInfo &HI : Handlers)
3233 HI.Handler->endBasicBlock(MBB);
3234}
3235
3236void AsmPrinter::emitVisibility(MCSymbol *Sym, unsigned Visibility,
3237 bool IsDefinition) const {
3238 MCSymbolAttr Attr = MCSA_Invalid;
3239
3240 switch (Visibility) {
3241 default: break;
3242 case GlobalValue::HiddenVisibility:
3243 if (IsDefinition)
3244 Attr = MAI->getHiddenVisibilityAttr();
3245 else
3246 Attr = MAI->getHiddenDeclarationVisibilityAttr();
3247 break;
3248 case GlobalValue::ProtectedVisibility:
3249 Attr = MAI->getProtectedVisibilityAttr();
3250 break;
3251 }
3252
3253 if (Attr != MCSA_Invalid)
3254 OutStreamer->emitSymbolAttribute(Sym, Attr);
3255}
3256
3257bool AsmPrinter::shouldEmitLabelForBasicBlock(
3258 const MachineBasicBlock &MBB) const {
3259 // With `-fbasic-block-sections=`, a label is needed for every non-entry block
3260 // in the labels mode (option `=labels`) and every section beginning in the
3261 // sections mode (`=all` and `=list=`).
3262 if ((MF->hasBBLabels() || MBB.isBeginSection()) && !MBB.isEntryBlock())
3263 return true;
3264 // A label is needed for any block with at least one predecessor (when that
3265 // predecessor is not the fallthrough predecessor, or if it is an EH funclet
3266 // entry, or if a label is forced).
3267 return !MBB.pred_empty() &&
3268 (!isBlockOnlyReachableByFallthrough(&MBB) || MBB.isEHFuncletEntry() ||
3269 MBB.hasLabelMustBeEmitted());
3270}
3271
3272/// isBlockOnlyReachableByFallthough - Return true if the basic block has
3273/// exactly one predecessor and the control transfer mechanism between
3274/// the predecessor and this block is a fall-through.
3275bool AsmPrinter::
3276isBlockOnlyReachableByFallthrough(const MachineBasicBlock *MBB) const {
3277 // If this is a landing pad, it isn't a fall through. If it has no preds,
3278 // then nothing falls through to it.
3279 if (MBB->isEHPad() || MBB->pred_empty())
3280 return false;
3281
3282 // If there isn't exactly one predecessor, it can't be a fall through.
3283 if (MBB->pred_size() > 1)
3284 return false;
3285
3286 // The predecessor has to be immediately before this block.
3287 MachineBasicBlock *Pred = *MBB->pred_begin();
3288 if (!Pred->isLayoutSuccessor(MBB))
3289 return false;
3290
3291 // If the block is completely empty, then it definitely does fall through.
3292 if (Pred->empty())
3293 return true;
3294
3295 // Check the terminators in the previous blocks
3296 for (const auto &MI : Pred->terminators()) {
3297 // If it is not a simple branch, we are in a table somewhere.
3298 if (!MI.isBranch() || MI.isIndirectBranch())
3299 return false;
3300
3301 // If we are the operands of one of the branches, this is not a fall
3302 // through. Note that targets with delay slots will usually bundle
3303 // terminators with the delay slot instruction.
3304 for (ConstMIBundleOperands OP(MI); OP.isValid(); ++OP) {
3305 if (OP->isJTI())
3306 return false;
3307 if (OP->isMBB() && OP->getMBB() == MBB)
3308 return false;
3309 }
3310 }
3311
3312 return true;
3313}
3314
3315GCMetadataPrinter *AsmPrinter::GetOrCreateGCPrinter(GCStrategy &S) {
3316 if (!S.usesMetadata())
3317 return nullptr;
3318
3319 gcp_map_type &GCMap = getGCMap(GCMetadataPrinters);
3320 gcp_map_type::iterator GCPI = GCMap.find(&S);
3321 if (GCPI != GCMap.end())
3322 return GCPI->second.get();
3323
3324 auto Name = S.getName();
3325
3326 for (const GCMetadataPrinterRegistry::entry &GCMetaPrinter :
3327 GCMetadataPrinterRegistry::entries())
3328 if (Name == GCMetaPrinter.getName()) {
3329 std::unique_ptr<GCMetadataPrinter> GMP = GCMetaPrinter.instantiate();
3330 GMP->S = &S;
3331 auto IterBool = GCMap.insert(std::make_pair(&S, std::move(GMP)));
3332 return IterBool.first->second.get();
3333 }
3334
3335 report_fatal_error("no GCMetadataPrinter registered for GC: " + Twine(Name));
3336}
3337
3338void AsmPrinter::emitStackMaps(StackMaps &SM) {
3339 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
3340 assert(MI && "AsmPrinter didn't require GCModuleInfo?")((MI && "AsmPrinter didn't require GCModuleInfo?") ? static_cast
<void> (0) : __assert_fail ("MI && \"AsmPrinter didn't require GCModuleInfo?\""
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 3340, __PRETTY_FUNCTION__))
;
3341 bool NeedsDefault = false;
3342 if (MI->begin() == MI->end())
3343 // No GC strategy, use the default format.
3344 NeedsDefault = true;
3345 else
3346 for (auto &I : *MI) {
3347 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*I))
3348 if (MP->emitStackMaps(SM, *this))
3349 continue;
3350 // The strategy doesn't have printer or doesn't emit custom stack maps.
3351 // Use the default format.
3352 NeedsDefault = true;
3353 }
3354
3355 if (NeedsDefault)
3356 SM.serializeToStackMapSection();
3357}
3358
3359/// Pin vtable to this file.
3360AsmPrinterHandler::~AsmPrinterHandler() = default;
3361
3362void AsmPrinterHandler::markFunctionEnd() {}
3363
3364// In the binary's "xray_instr_map" section, an array of these function entries
3365// describes each instrumentation point. When XRay patches your code, the index
3366// into this table will be given to your handler as a patch point identifier.
3367void AsmPrinter::XRayFunctionEntry::emit(int Bytes, MCStreamer *Out) const {
3368 auto Kind8 = static_cast<uint8_t>(Kind);
3369 Out->emitBinaryData(StringRef(reinterpret_cast<const char *>(&Kind8), 1));
3370 Out->emitBinaryData(
3371 StringRef(reinterpret_cast<const char *>(&AlwaysInstrument), 1));
3372 Out->emitBinaryData(StringRef(reinterpret_cast<const char *>(&Version), 1));
3373 auto Padding = (4 * Bytes) - ((2 * Bytes) + 3);
3374 assert(Padding >= 0 && "Instrumentation map entry > 4 * Word Size")((Padding >= 0 && "Instrumentation map entry > 4 * Word Size"
) ? static_cast<void> (0) : __assert_fail ("Padding >= 0 && \"Instrumentation map entry > 4 * Word Size\""
, "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 3374, __PRETTY_FUNCTION__))
;
3375 Out->emitZeros(Padding);
3376}
3377
3378void AsmPrinter::emitXRayTable() {
3379 if (Sleds.empty())
3380 return;
3381
3382 auto PrevSection = OutStreamer->getCurrentSectionOnly();
3383 const Function &F = MF->getFunction();
3384 MCSection *InstMap = nullptr;
3385 MCSection *FnSledIndex = nullptr;
3386 const Triple &TT = TM.getTargetTriple();
3387 // Use PC-relative addresses on all targets.
3388 if (TT.isOSBinFormatELF()) {
3389 auto LinkedToSym = cast<MCSymbolELF>(CurrentFnSym);
3390 auto Flags = ELF::SHF_ALLOC | ELF::SHF_LINK_ORDER;
3391 StringRef GroupName;
3392 if (F.hasComdat()) {
3393 Flags |= ELF::SHF_GROUP;
3394 GroupName = F.getComdat()->getName();
3395 }
3396 InstMap = OutContext.getELFSection("xray_instr_map", ELF::SHT_PROGBITS,
3397 Flags, 0, GroupName, F.hasComdat(),
3398 MCSection::NonUniqueID, LinkedToSym);
3399
3400 if (!TM.Options.XRayOmitFunctionIndex)
3401 FnSledIndex = OutContext.getELFSection(
3402 "xray_fn_idx", ELF::SHT_PROGBITS, Flags | ELF::SHF_WRITE, 0,
3403 GroupName, F.hasComdat(), MCSection::NonUniqueID, LinkedToSym);
3404 } else if (MF->getSubtarget().getTargetTriple().isOSBinFormatMachO()) {
3405 InstMap = OutContext.getMachOSection("__DATA", "xray_instr_map", 0,
3406 SectionKind::getReadOnlyWithRel());
3407 if (!TM.Options.XRayOmitFunctionIndex)
3408 FnSledIndex = OutContext.getMachOSection(
3409 "__DATA", "xray_fn_idx", 0, SectionKind::getReadOnlyWithRel());
3410 } else {
3411 llvm_unreachable("Unsupported target")::llvm::llvm_unreachable_internal("Unsupported target", "/build/llvm-toolchain-snapshot-13~++20210405022414+5f57793c4fe4/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 3411)
;
3412 }
3413
3414 auto WordSizeBytes = MAI->getCodePointerSize();
3415
3416 // Now we switch to the instrumentation map section. Because this is done
3417 // per-function, we are able to create an index entry that will represent the
3418 // range of sleds associated with a function.
3419 auto &Ctx = OutContext;
3420 MCSymbol *SledsStart = OutContext.createTempSymbol("xray_sleds_start", true);
3421 OutStreamer->SwitchSection(InstMap);
3422 OutStreamer->emitLabel(SledsStart);
3423 for (const auto &Sled : Sleds) {
3424 MCSymbol *Dot = Ctx.createTempSymbol();
3425 OutStreamer->emitLabel(Dot);
3426 OutStreamer->emitValueImpl(
3427 MCBinaryExpr::createSub(MCSymbolRefExpr::create(Sled.Sled, Ctx),
3428 MCSymbolRefExpr::create(Dot, Ctx), Ctx),
3429 WordSizeBytes);
3430 OutStreamer->emitValueImpl(
3431 MCBinaryExpr::createSub(
3432 MCSymbolRefExpr::create(CurrentFnBegin, Ctx),
3433 MCBinaryExpr::createAdd(MCSymbolRefExpr::create(Dot, Ctx),
3434 MCConstantExpr::create(WordSizeBytes, Ctx),
3435 Ctx),
3436 Ctx),
3437 WordSizeBytes);
3438 Sled.emit(WordSizeBytes, OutStreamer.get());
3439 }
3440 MCSymbol *SledsEnd = OutContext.createTempSymbol("xray_sleds_end", true);
3441 OutStreamer->emitLabel(SledsEnd);
3442
3443 // We then emit a single entry in the index per function. We use the symbols
3444 // that bound the instrumentation map as the range for a specific function.
3445 // Each entry here will be 2 * word size aligned, as we're writing down two
3446 // pointers. This should work for both 32-bit and 64-bit platforms.
3447 if (FnSledIndex) {
3448 OutStreamer->SwitchSection(FnSledIndex);
3449 OutStreamer->emitCodeAlignment(2 * WordSizeBytes);
3450 OutStreamer->emitSymbolValue(SledsStart, WordSizeBytes, false);
3451 OutStreamer->emitSymbolValue(SledsEnd, WordSizeBytes, false);
3452 OutStreamer->SwitchSection(PrevSection);
3453 }
3454 Sleds.clear();
3455}
3456
3457void AsmPrinter::recordSled(MCSymbol *Sled, const MachineInstr &MI,
3458 SledKind Kind, uint8_t Version) {
3459 const Function &F = MI.getMF()->getFunction();
3460 auto Attr = F.getFnAttribute("function-instrument");
3461 bool LogArgs = F.hasFnAttribute("xray-log-args");
3462 bool AlwaysInstrument =
3463 Attr.isStringAttribute() && Attr.getValueAsString() == "xray-always";
3464 if (Kind == SledKind::FUNCTION_ENTER && LogArgs)
3465 Kind = SledKind::LOG_ARGS_ENTER;
3466 Sleds.emplace_back(XRayFunctionEntry{Sled, CurrentFnSym, Kind,
3467 AlwaysInstrument, &F, Version});
3468}
3469
3470void AsmPrinter::emitPatchableFunctionEntries() {
3471 const Function &F = MF->getFunction();
3472 unsigned PatchableFunctionPrefix = 0, PatchableFunctionEntry = 0;
3473 (void)F.getFnAttribute("patchable-function-prefix")
3474 .getValueAsString()
3475 .getAsInteger(10, PatchableFunctionPrefix);
3476 (void)F.getFnAttribute("patchable-function-entry")
3477 .getValueAsString()
3478 .getAsInteger(10, PatchableFunctionEntry);
3479 if (!PatchableFunctionPrefix && !PatchableFunctionEntry)
3480 return;
3481 const unsigned PointerSize = getPointerSize();
3482 if (TM.getTargetTriple().isOSBinFormatELF()) {
3483 auto Flags = ELF::SHF_WRITE | ELF::SHF_ALLOC;
3484 const MCSymbolELF *LinkedToSym = nullptr;
3485 StringRef GroupName;
3486
3487 // GNU as < 2.35 did not support section flag 'o'. GNU ld < 2.36 did not
3488 // support mixed SHF_LINK_ORDER and non-SHF_LINK_ORDER sections.
3489 if (MAI->useIntegratedAssembler() || MAI->binutilsIsAtLeast(2, 36)) {
3490 Flags |= ELF::SHF_LINK_ORDER;
3491 if (F.hasComdat()) {
3492 Flags |= ELF::SHF_GROUP;
3493 GroupName = F.getComdat()->getName();
3494 }
3495 LinkedToSym = cast<MCSymbolELF>(CurrentFnSym);
3496 }
3497 OutStreamer->SwitchSection(OutContext.getELFSection(
3498 "__patchable_function_entries", ELF::SHT_PROGBITS, Flags, 0, GroupName,
3499 F.hasComdat(), MCSection::NonUniqueID, LinkedToSym));
3500 emitAlignment(Align(PointerSize));
3501 OutStreamer->emitSymbolValue(CurrentPatchableFunctionEntrySym, PointerSize);
3502 }
3503}
3504
3505uint16_t AsmPrinter::getDwarfVersion() const {
3506 return OutStreamer->getContext().getDwarfVersion();
3507}
3508
3509void AsmPrinter::setDwarfVersion(uint16_t Version) {
3510 OutStreamer->getContext().setDwarfVersion(Version);
3511}
3512
3513bool AsmPrinter::isDwarf64() const {
3514 return OutStreamer->getContext().getDwarfFormat() == dwarf::DWARF64;
3515}
3516
3517unsigned int AsmPrinter::getDwarfOffsetByteSize() const {
3518 return dwarf::getDwarfOffsetByteSize(
3519 OutStreamer->getContext().getDwarfFormat());
3520}
3521
3522unsigned int AsmPrinter::getUnitLengthFieldByteSize() const {
3523 return dwarf::getUnitLengthFieldByteSize(
3524 OutStreamer->getContext().getDwarfFormat());
3525}