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authorpatrick <patrick@openbsd.org>2020-08-03 14:31:31 +0000
committerpatrick <patrick@openbsd.org>2020-08-03 14:31:31 +0000
commite5dd70708596ae51455a0ffa086a00c5b29f8583 (patch)
tree5d676f27b570bacf71e786c3b5cff3e6f6679b59 /gnu/llvm/clang/lib/CodeGen/CodeGenFunction.cpp
parentImport LLVM 10.0.0 release including clang, lld and lldb. (diff)
downloadwireguard-openbsd-e5dd70708596ae51455a0ffa086a00c5b29f8583.tar.xz
wireguard-openbsd-e5dd70708596ae51455a0ffa086a00c5b29f8583.zip
Import LLVM 10.0.0 release including clang, lld and lldb.
ok hackroom tested by plenty
Diffstat (limited to 'gnu/llvm/clang/lib/CodeGen/CodeGenFunction.cpp')
-rw-r--r--gnu/llvm/clang/lib/CodeGen/CodeGenFunction.cpp2495
1 files changed, 2495 insertions, 0 deletions
diff --git a/gnu/llvm/clang/lib/CodeGen/CodeGenFunction.cpp b/gnu/llvm/clang/lib/CodeGen/CodeGenFunction.cpp
new file mode 100644
index 00000000000..648e6d9c214
--- /dev/null
+++ b/gnu/llvm/clang/lib/CodeGen/CodeGenFunction.cpp
@@ -0,0 +1,2495 @@
+//===--- CodeGenFunction.cpp - Emit LLVM Code from ASTs for a Function ----===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This coordinates the per-function state used while generating code.
+//
+//===----------------------------------------------------------------------===//
+
+#include "CodeGenFunction.h"
+#include "CGBlocks.h"
+#include "CGCUDARuntime.h"
+#include "CGCXXABI.h"
+#include "CGCleanup.h"
+#include "CGDebugInfo.h"
+#include "CGOpenMPRuntime.h"
+#include "CodeGenModule.h"
+#include "CodeGenPGO.h"
+#include "TargetInfo.h"
+#include "clang/AST/ASTContext.h"
+#include "clang/AST/ASTLambda.h"
+#include "clang/AST/Attr.h"
+#include "clang/AST/Decl.h"
+#include "clang/AST/DeclCXX.h"
+#include "clang/AST/StmtCXX.h"
+#include "clang/AST/StmtObjC.h"
+#include "clang/Basic/Builtins.h"
+#include "clang/Basic/CodeGenOptions.h"
+#include "clang/Basic/TargetInfo.h"
+#include "clang/CodeGen/CGFunctionInfo.h"
+#include "clang/Frontend/FrontendDiagnostic.h"
+#include "llvm/IR/DataLayout.h"
+#include "llvm/IR/Dominators.h"
+#include "llvm/IR/FPEnv.h"
+#include "llvm/IR/IntrinsicInst.h"
+#include "llvm/IR/Intrinsics.h"
+#include "llvm/IR/MDBuilder.h"
+#include "llvm/IR/Operator.h"
+#include "llvm/Transforms/Utils/PromoteMemToReg.h"
+using namespace clang;
+using namespace CodeGen;
+
+/// shouldEmitLifetimeMarkers - Decide whether we need emit the life-time
+/// markers.
+static bool shouldEmitLifetimeMarkers(const CodeGenOptions &CGOpts,
+ const LangOptions &LangOpts) {
+ if (CGOpts.DisableLifetimeMarkers)
+ return false;
+
+ // Sanitizers may use markers.
+ if (CGOpts.SanitizeAddressUseAfterScope ||
+ LangOpts.Sanitize.has(SanitizerKind::HWAddress) ||
+ LangOpts.Sanitize.has(SanitizerKind::Memory))
+ return true;
+
+ // For now, only in optimized builds.
+ return CGOpts.OptimizationLevel != 0;
+}
+
+CodeGenFunction::CodeGenFunction(CodeGenModule &cgm, bool suppressNewContext)
+ : CodeGenTypeCache(cgm), CGM(cgm), Target(cgm.getTarget()),
+ Builder(cgm, cgm.getModule().getContext(), llvm::ConstantFolder(),
+ CGBuilderInserterTy(this)),
+ SanOpts(CGM.getLangOpts().Sanitize), DebugInfo(CGM.getModuleDebugInfo()),
+ PGO(cgm), ShouldEmitLifetimeMarkers(shouldEmitLifetimeMarkers(
+ CGM.getCodeGenOpts(), CGM.getLangOpts())) {
+ if (!suppressNewContext)
+ CGM.getCXXABI().getMangleContext().startNewFunction();
+
+ llvm::FastMathFlags FMF;
+ if (CGM.getLangOpts().FastMath)
+ FMF.setFast();
+ if (CGM.getLangOpts().FiniteMathOnly) {
+ FMF.setNoNaNs();
+ FMF.setNoInfs();
+ }
+ if (CGM.getCodeGenOpts().NoNaNsFPMath) {
+ FMF.setNoNaNs();
+ }
+ if (CGM.getCodeGenOpts().NoSignedZeros) {
+ FMF.setNoSignedZeros();
+ }
+ if (CGM.getCodeGenOpts().ReciprocalMath) {
+ FMF.setAllowReciprocal();
+ }
+ if (CGM.getCodeGenOpts().Reassociate) {
+ FMF.setAllowReassoc();
+ }
+ Builder.setFastMathFlags(FMF);
+ SetFPModel();
+}
+
+CodeGenFunction::~CodeGenFunction() {
+ assert(LifetimeExtendedCleanupStack.empty() && "failed to emit a cleanup");
+
+ // If there are any unclaimed block infos, go ahead and destroy them
+ // now. This can happen if IR-gen gets clever and skips evaluating
+ // something.
+ if (FirstBlockInfo)
+ destroyBlockInfos(FirstBlockInfo);
+
+ if (getLangOpts().OpenMP && CurFn)
+ CGM.getOpenMPRuntime().functionFinished(*this);
+}
+
+// Map the LangOption for rounding mode into
+// the corresponding enum in the IR.
+static llvm::fp::RoundingMode ToConstrainedRoundingMD(
+ LangOptions::FPRoundingModeKind Kind) {
+
+ switch (Kind) {
+ case LangOptions::FPR_ToNearest: return llvm::fp::rmToNearest;
+ case LangOptions::FPR_Downward: return llvm::fp::rmDownward;
+ case LangOptions::FPR_Upward: return llvm::fp::rmUpward;
+ case LangOptions::FPR_TowardZero: return llvm::fp::rmTowardZero;
+ case LangOptions::FPR_Dynamic: return llvm::fp::rmDynamic;
+ }
+ llvm_unreachable("Unsupported FP RoundingMode");
+}
+
+// Map the LangOption for exception behavior into
+// the corresponding enum in the IR.
+static llvm::fp::ExceptionBehavior ToConstrainedExceptMD(
+ LangOptions::FPExceptionModeKind Kind) {
+
+ switch (Kind) {
+ case LangOptions::FPE_Ignore: return llvm::fp::ebIgnore;
+ case LangOptions::FPE_MayTrap: return llvm::fp::ebMayTrap;
+ case LangOptions::FPE_Strict: return llvm::fp::ebStrict;
+ }
+ llvm_unreachable("Unsupported FP Exception Behavior");
+}
+
+void CodeGenFunction::SetFPModel() {
+ auto fpRoundingMode = ToConstrainedRoundingMD(
+ getLangOpts().getFPRoundingMode());
+ auto fpExceptionBehavior = ToConstrainedExceptMD(
+ getLangOpts().getFPExceptionMode());
+
+ if (fpExceptionBehavior == llvm::fp::ebIgnore &&
+ fpRoundingMode == llvm::fp::rmToNearest)
+ // Constrained intrinsics are not used.
+ ;
+ else {
+ Builder.setIsFPConstrained(true);
+ Builder.setDefaultConstrainedRounding(fpRoundingMode);
+ Builder.setDefaultConstrainedExcept(fpExceptionBehavior);
+ }
+}
+
+CharUnits CodeGenFunction::getNaturalPointeeTypeAlignment(QualType T,
+ LValueBaseInfo *BaseInfo,
+ TBAAAccessInfo *TBAAInfo) {
+ return getNaturalTypeAlignment(T->getPointeeType(), BaseInfo, TBAAInfo,
+ /* forPointeeType= */ true);
+}
+
+CharUnits CodeGenFunction::getNaturalTypeAlignment(QualType T,
+ LValueBaseInfo *BaseInfo,
+ TBAAAccessInfo *TBAAInfo,
+ bool forPointeeType) {
+ if (TBAAInfo)
+ *TBAAInfo = CGM.getTBAAAccessInfo(T);
+
+ // Honor alignment typedef attributes even on incomplete types.
+ // We also honor them straight for C++ class types, even as pointees;
+ // there's an expressivity gap here.
+ if (auto TT = T->getAs<TypedefType>()) {
+ if (auto Align = TT->getDecl()->getMaxAlignment()) {
+ if (BaseInfo)
+ *BaseInfo = LValueBaseInfo(AlignmentSource::AttributedType);
+ return getContext().toCharUnitsFromBits(Align);
+ }
+ }
+
+ if (BaseInfo)
+ *BaseInfo = LValueBaseInfo(AlignmentSource::Type);
+
+ CharUnits Alignment;
+ if (T->isIncompleteType()) {
+ Alignment = CharUnits::One(); // Shouldn't be used, but pessimistic is best.
+ } else {
+ // For C++ class pointees, we don't know whether we're pointing at a
+ // base or a complete object, so we generally need to use the
+ // non-virtual alignment.
+ const CXXRecordDecl *RD;
+ if (forPointeeType && (RD = T->getAsCXXRecordDecl())) {
+ Alignment = CGM.getClassPointerAlignment(RD);
+ } else {
+ Alignment = getContext().getTypeAlignInChars(T);
+ if (T.getQualifiers().hasUnaligned())
+ Alignment = CharUnits::One();
+ }
+
+ // Cap to the global maximum type alignment unless the alignment
+ // was somehow explicit on the type.
+ if (unsigned MaxAlign = getLangOpts().MaxTypeAlign) {
+ if (Alignment.getQuantity() > MaxAlign &&
+ !getContext().isAlignmentRequired(T))
+ Alignment = CharUnits::fromQuantity(MaxAlign);
+ }
+ }
+ return Alignment;
+}
+
+LValue CodeGenFunction::MakeNaturalAlignAddrLValue(llvm::Value *V, QualType T) {
+ LValueBaseInfo BaseInfo;
+ TBAAAccessInfo TBAAInfo;
+ CharUnits Alignment = getNaturalTypeAlignment(T, &BaseInfo, &TBAAInfo);
+ return LValue::MakeAddr(Address(V, Alignment), T, getContext(), BaseInfo,
+ TBAAInfo);
+}
+
+/// Given a value of type T* that may not be to a complete object,
+/// construct an l-value with the natural pointee alignment of T.
+LValue
+CodeGenFunction::MakeNaturalAlignPointeeAddrLValue(llvm::Value *V, QualType T) {
+ LValueBaseInfo BaseInfo;
+ TBAAAccessInfo TBAAInfo;
+ CharUnits Align = getNaturalTypeAlignment(T, &BaseInfo, &TBAAInfo,
+ /* forPointeeType= */ true);
+ return MakeAddrLValue(Address(V, Align), T, BaseInfo, TBAAInfo);
+}
+
+
+llvm::Type *CodeGenFunction::ConvertTypeForMem(QualType T) {
+ return CGM.getTypes().ConvertTypeForMem(T);
+}
+
+llvm::Type *CodeGenFunction::ConvertType(QualType T) {
+ return CGM.getTypes().ConvertType(T);
+}
+
+TypeEvaluationKind CodeGenFunction::getEvaluationKind(QualType type) {
+ type = type.getCanonicalType();
+ while (true) {
+ switch (type->getTypeClass()) {
+#define TYPE(name, parent)
+#define ABSTRACT_TYPE(name, parent)
+#define NON_CANONICAL_TYPE(name, parent) case Type::name:
+#define DEPENDENT_TYPE(name, parent) case Type::name:
+#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(name, parent) case Type::name:
+#include "clang/AST/TypeNodes.inc"
+ llvm_unreachable("non-canonical or dependent type in IR-generation");
+
+ case Type::Auto:
+ case Type::DeducedTemplateSpecialization:
+ llvm_unreachable("undeduced type in IR-generation");
+
+ // Various scalar types.
+ case Type::Builtin:
+ case Type::Pointer:
+ case Type::BlockPointer:
+ case Type::LValueReference:
+ case Type::RValueReference:
+ case Type::MemberPointer:
+ case Type::Vector:
+ case Type::ExtVector:
+ case Type::FunctionProto:
+ case Type::FunctionNoProto:
+ case Type::Enum:
+ case Type::ObjCObjectPointer:
+ case Type::Pipe:
+ return TEK_Scalar;
+
+ // Complexes.
+ case Type::Complex:
+ return TEK_Complex;
+
+ // Arrays, records, and Objective-C objects.
+ case Type::ConstantArray:
+ case Type::IncompleteArray:
+ case Type::VariableArray:
+ case Type::Record:
+ case Type::ObjCObject:
+ case Type::ObjCInterface:
+ return TEK_Aggregate;
+
+ // We operate on atomic values according to their underlying type.
+ case Type::Atomic:
+ type = cast<AtomicType>(type)->getValueType();
+ continue;
+ }
+ llvm_unreachable("unknown type kind!");
+ }
+}
+
+llvm::DebugLoc CodeGenFunction::EmitReturnBlock() {
+ // For cleanliness, we try to avoid emitting the return block for
+ // simple cases.
+ llvm::BasicBlock *CurBB = Builder.GetInsertBlock();
+
+ if (CurBB) {
+ assert(!CurBB->getTerminator() && "Unexpected terminated block.");
+
+ // We have a valid insert point, reuse it if it is empty or there are no
+ // explicit jumps to the return block.
+ if (CurBB->empty() || ReturnBlock.getBlock()->use_empty()) {
+ ReturnBlock.getBlock()->replaceAllUsesWith(CurBB);
+ delete ReturnBlock.getBlock();
+ ReturnBlock = JumpDest();
+ } else
+ EmitBlock(ReturnBlock.getBlock());
+ return llvm::DebugLoc();
+ }
+
+ // Otherwise, if the return block is the target of a single direct
+ // branch then we can just put the code in that block instead. This
+ // cleans up functions which started with a unified return block.
+ if (ReturnBlock.getBlock()->hasOneUse()) {
+ llvm::BranchInst *BI =
+ dyn_cast<llvm::BranchInst>(*ReturnBlock.getBlock()->user_begin());
+ if (BI && BI->isUnconditional() &&
+ BI->getSuccessor(0) == ReturnBlock.getBlock()) {
+ // Record/return the DebugLoc of the simple 'return' expression to be used
+ // later by the actual 'ret' instruction.
+ llvm::DebugLoc Loc = BI->getDebugLoc();
+ Builder.SetInsertPoint(BI->getParent());
+ BI->eraseFromParent();
+ delete ReturnBlock.getBlock();
+ ReturnBlock = JumpDest();
+ return Loc;
+ }
+ }
+
+ // FIXME: We are at an unreachable point, there is no reason to emit the block
+ // unless it has uses. However, we still need a place to put the debug
+ // region.end for now.
+
+ EmitBlock(ReturnBlock.getBlock());
+ return llvm::DebugLoc();
+}
+
+static void EmitIfUsed(CodeGenFunction &CGF, llvm::BasicBlock *BB) {
+ if (!BB) return;
+ if (!BB->use_empty())
+ return CGF.CurFn->getBasicBlockList().push_back(BB);
+ delete BB;
+}
+
+void CodeGenFunction::FinishFunction(SourceLocation EndLoc) {
+ assert(BreakContinueStack.empty() &&
+ "mismatched push/pop in break/continue stack!");
+
+ bool OnlySimpleReturnStmts = NumSimpleReturnExprs > 0
+ && NumSimpleReturnExprs == NumReturnExprs
+ && ReturnBlock.getBlock()->use_empty();
+ // Usually the return expression is evaluated before the cleanup
+ // code. If the function contains only a simple return statement,
+ // such as a constant, the location before the cleanup code becomes
+ // the last useful breakpoint in the function, because the simple
+ // return expression will be evaluated after the cleanup code. To be
+ // safe, set the debug location for cleanup code to the location of
+ // the return statement. Otherwise the cleanup code should be at the
+ // end of the function's lexical scope.
+ //
+ // If there are multiple branches to the return block, the branch
+ // instructions will get the location of the return statements and
+ // all will be fine.
+ if (CGDebugInfo *DI = getDebugInfo()) {
+ if (OnlySimpleReturnStmts)
+ DI->EmitLocation(Builder, LastStopPoint);
+ else
+ DI->EmitLocation(Builder, EndLoc);
+ }
+
+ // Pop any cleanups that might have been associated with the
+ // parameters. Do this in whatever block we're currently in; it's
+ // important to do this before we enter the return block or return
+ // edges will be *really* confused.
+ bool HasCleanups = EHStack.stable_begin() != PrologueCleanupDepth;
+ bool HasOnlyLifetimeMarkers =
+ HasCleanups && EHStack.containsOnlyLifetimeMarkers(PrologueCleanupDepth);
+ bool EmitRetDbgLoc = !HasCleanups || HasOnlyLifetimeMarkers;
+ if (HasCleanups) {
+ // Make sure the line table doesn't jump back into the body for
+ // the ret after it's been at EndLoc.
+ Optional<ApplyDebugLocation> AL;
+ if (CGDebugInfo *DI = getDebugInfo()) {
+ if (OnlySimpleReturnStmts)
+ DI->EmitLocation(Builder, EndLoc);
+ else
+ // We may not have a valid end location. Try to apply it anyway, and
+ // fall back to an artificial location if needed.
+ AL = ApplyDebugLocation::CreateDefaultArtificial(*this, EndLoc);
+ }
+
+ PopCleanupBlocks(PrologueCleanupDepth);
+ }
+
+ // Emit function epilog (to return).
+ llvm::DebugLoc Loc = EmitReturnBlock();
+
+ if (ShouldInstrumentFunction()) {
+ if (CGM.getCodeGenOpts().InstrumentFunctions)
+ CurFn->addFnAttr("instrument-function-exit", "__cyg_profile_func_exit");
+ if (CGM.getCodeGenOpts().InstrumentFunctionsAfterInlining)
+ CurFn->addFnAttr("instrument-function-exit-inlined",
+ "__cyg_profile_func_exit");
+ }
+
+ // Emit debug descriptor for function end.
+ if (CGDebugInfo *DI = getDebugInfo())
+ DI->EmitFunctionEnd(Builder, CurFn);
+
+ // Reset the debug location to that of the simple 'return' expression, if any
+ // rather than that of the end of the function's scope '}'.
+ ApplyDebugLocation AL(*this, Loc);
+ EmitFunctionEpilog(*CurFnInfo, EmitRetDbgLoc, EndLoc);
+ EmitEndEHSpec(CurCodeDecl);
+
+ assert(EHStack.empty() &&
+ "did not remove all scopes from cleanup stack!");
+
+ // If someone did an indirect goto, emit the indirect goto block at the end of
+ // the function.
+ if (IndirectBranch) {
+ EmitBlock(IndirectBranch->getParent());
+ Builder.ClearInsertionPoint();
+ }
+
+ // If some of our locals escaped, insert a call to llvm.localescape in the
+ // entry block.
+ if (!EscapedLocals.empty()) {
+ // Invert the map from local to index into a simple vector. There should be
+ // no holes.
+ SmallVector<llvm::Value *, 4> EscapeArgs;
+ EscapeArgs.resize(EscapedLocals.size());
+ for (auto &Pair : EscapedLocals)
+ EscapeArgs[Pair.second] = Pair.first;
+ llvm::Function *FrameEscapeFn = llvm::Intrinsic::getDeclaration(
+ &CGM.getModule(), llvm::Intrinsic::localescape);
+ CGBuilderTy(*this, AllocaInsertPt).CreateCall(FrameEscapeFn, EscapeArgs);
+ }
+
+ // Remove the AllocaInsertPt instruction, which is just a convenience for us.
+ llvm::Instruction *Ptr = AllocaInsertPt;
+ AllocaInsertPt = nullptr;
+ Ptr->eraseFromParent();
+
+ // If someone took the address of a label but never did an indirect goto, we
+ // made a zero entry PHI node, which is illegal, zap it now.
+ if (IndirectBranch) {
+ llvm::PHINode *PN = cast<llvm::PHINode>(IndirectBranch->getAddress());
+ if (PN->getNumIncomingValues() == 0) {
+ PN->replaceAllUsesWith(llvm::UndefValue::get(PN->getType()));
+ PN->eraseFromParent();
+ }
+ }
+
+ EmitIfUsed(*this, EHResumeBlock);
+ EmitIfUsed(*this, TerminateLandingPad);
+ EmitIfUsed(*this, TerminateHandler);
+ EmitIfUsed(*this, UnreachableBlock);
+
+ for (const auto &FuncletAndParent : TerminateFunclets)
+ EmitIfUsed(*this, FuncletAndParent.second);
+
+ if (CGM.getCodeGenOpts().EmitDeclMetadata)
+ EmitDeclMetadata();
+
+ for (SmallVectorImpl<std::pair<llvm::Instruction *, llvm::Value *> >::iterator
+ I = DeferredReplacements.begin(),
+ E = DeferredReplacements.end();
+ I != E; ++I) {
+ I->first->replaceAllUsesWith(I->second);
+ I->first->eraseFromParent();
+ }
+
+ // Eliminate CleanupDestSlot alloca by replacing it with SSA values and
+ // PHIs if the current function is a coroutine. We don't do it for all
+ // functions as it may result in slight increase in numbers of instructions
+ // if compiled with no optimizations. We do it for coroutine as the lifetime
+ // of CleanupDestSlot alloca make correct coroutine frame building very
+ // difficult.
+ if (NormalCleanupDest.isValid() && isCoroutine()) {
+ llvm::DominatorTree DT(*CurFn);
+ llvm::PromoteMemToReg(
+ cast<llvm::AllocaInst>(NormalCleanupDest.getPointer()), DT);
+ NormalCleanupDest = Address::invalid();
+ }
+
+ // Scan function arguments for vector width.
+ for (llvm::Argument &A : CurFn->args())
+ if (auto *VT = dyn_cast<llvm::VectorType>(A.getType()))
+ LargestVectorWidth = std::max((uint64_t)LargestVectorWidth,
+ VT->getPrimitiveSizeInBits().getFixedSize());
+
+ // Update vector width based on return type.
+ if (auto *VT = dyn_cast<llvm::VectorType>(CurFn->getReturnType()))
+ LargestVectorWidth = std::max((uint64_t)LargestVectorWidth,
+ VT->getPrimitiveSizeInBits().getFixedSize());
+
+ // Add the required-vector-width attribute. This contains the max width from:
+ // 1. min-vector-width attribute used in the source program.
+ // 2. Any builtins used that have a vector width specified.
+ // 3. Values passed in and out of inline assembly.
+ // 4. Width of vector arguments and return types for this function.
+ // 5. Width of vector aguments and return types for functions called by this
+ // function.
+ CurFn->addFnAttr("min-legal-vector-width", llvm::utostr(LargestVectorWidth));
+
+ // If we generated an unreachable return block, delete it now.
+ if (ReturnBlock.isValid() && ReturnBlock.getBlock()->use_empty()) {
+ Builder.ClearInsertionPoint();
+ ReturnBlock.getBlock()->eraseFromParent();
+ }
+ if (ReturnValue.isValid()) {
+ auto *RetAlloca = dyn_cast<llvm::AllocaInst>(ReturnValue.getPointer());
+ if (RetAlloca && RetAlloca->use_empty()) {
+ RetAlloca->eraseFromParent();
+ ReturnValue = Address::invalid();
+ }
+ }
+}
+
+/// ShouldInstrumentFunction - Return true if the current function should be
+/// instrumented with __cyg_profile_func_* calls
+bool CodeGenFunction::ShouldInstrumentFunction() {
+ if (!CGM.getCodeGenOpts().InstrumentFunctions &&
+ !CGM.getCodeGenOpts().InstrumentFunctionsAfterInlining &&
+ !CGM.getCodeGenOpts().InstrumentFunctionEntryBare)
+ return false;
+ if (!CurFuncDecl || CurFuncDecl->hasAttr<NoInstrumentFunctionAttr>())
+ return false;
+ return true;
+}
+
+/// ShouldXRayInstrument - Return true if the current function should be
+/// instrumented with XRay nop sleds.
+bool CodeGenFunction::ShouldXRayInstrumentFunction() const {
+ return CGM.getCodeGenOpts().XRayInstrumentFunctions;
+}
+
+/// AlwaysEmitXRayCustomEvents - Return true if we should emit IR for calls to
+/// the __xray_customevent(...) builtin calls, when doing XRay instrumentation.
+bool CodeGenFunction::AlwaysEmitXRayCustomEvents() const {
+ return CGM.getCodeGenOpts().XRayInstrumentFunctions &&
+ (CGM.getCodeGenOpts().XRayAlwaysEmitCustomEvents ||
+ CGM.getCodeGenOpts().XRayInstrumentationBundle.Mask ==
+ XRayInstrKind::Custom);
+}
+
+bool CodeGenFunction::AlwaysEmitXRayTypedEvents() const {
+ return CGM.getCodeGenOpts().XRayInstrumentFunctions &&
+ (CGM.getCodeGenOpts().XRayAlwaysEmitTypedEvents ||
+ CGM.getCodeGenOpts().XRayInstrumentationBundle.Mask ==
+ XRayInstrKind::Typed);
+}
+
+llvm::Constant *
+CodeGenFunction::EncodeAddrForUseInPrologue(llvm::Function *F,
+ llvm::Constant *Addr) {
+ // Addresses stored in prologue data can't require run-time fixups and must
+ // be PC-relative. Run-time fixups are undesirable because they necessitate
+ // writable text segments, which are unsafe. And absolute addresses are
+ // undesirable because they break PIE mode.
+
+ // Add a layer of indirection through a private global. Taking its address
+ // won't result in a run-time fixup, even if Addr has linkonce_odr linkage.
+ auto *GV = new llvm::GlobalVariable(CGM.getModule(), Addr->getType(),
+ /*isConstant=*/true,
+ llvm::GlobalValue::PrivateLinkage, Addr);
+
+ // Create a PC-relative address.
+ auto *GOTAsInt = llvm::ConstantExpr::getPtrToInt(GV, IntPtrTy);
+ auto *FuncAsInt = llvm::ConstantExpr::getPtrToInt(F, IntPtrTy);
+ auto *PCRelAsInt = llvm::ConstantExpr::getSub(GOTAsInt, FuncAsInt);
+ return (IntPtrTy == Int32Ty)
+ ? PCRelAsInt
+ : llvm::ConstantExpr::getTrunc(PCRelAsInt, Int32Ty);
+}
+
+llvm::Value *
+CodeGenFunction::DecodeAddrUsedInPrologue(llvm::Value *F,
+ llvm::Value *EncodedAddr) {
+ // Reconstruct the address of the global.
+ auto *PCRelAsInt = Builder.CreateSExt(EncodedAddr, IntPtrTy);
+ auto *FuncAsInt = Builder.CreatePtrToInt(F, IntPtrTy, "func_addr.int");
+ auto *GOTAsInt = Builder.CreateAdd(PCRelAsInt, FuncAsInt, "global_addr.int");
+ auto *GOTAddr = Builder.CreateIntToPtr(GOTAsInt, Int8PtrPtrTy, "global_addr");
+
+ // Load the original pointer through the global.
+ return Builder.CreateLoad(Address(GOTAddr, getPointerAlign()),
+ "decoded_addr");
+}
+
+void CodeGenFunction::EmitOpenCLKernelMetadata(const FunctionDecl *FD,
+ llvm::Function *Fn)
+{
+ if (!FD->hasAttr<OpenCLKernelAttr>())
+ return;
+
+ llvm::LLVMContext &Context = getLLVMContext();
+
+ CGM.GenOpenCLArgMetadata(Fn, FD, this);
+
+ if (const VecTypeHintAttr *A = FD->getAttr<VecTypeHintAttr>()) {
+ QualType HintQTy = A->getTypeHint();
+ const ExtVectorType *HintEltQTy = HintQTy->getAs<ExtVectorType>();
+ bool IsSignedInteger =
+ HintQTy->isSignedIntegerType() ||
+ (HintEltQTy && HintEltQTy->getElementType()->isSignedIntegerType());
+ llvm::Metadata *AttrMDArgs[] = {
+ llvm::ConstantAsMetadata::get(llvm::UndefValue::get(
+ CGM.getTypes().ConvertType(A->getTypeHint()))),
+ llvm::ConstantAsMetadata::get(llvm::ConstantInt::get(
+ llvm::IntegerType::get(Context, 32),
+ llvm::APInt(32, (uint64_t)(IsSignedInteger ? 1 : 0))))};
+ Fn->setMetadata("vec_type_hint", llvm::MDNode::get(Context, AttrMDArgs));
+ }
+
+ if (const WorkGroupSizeHintAttr *A = FD->getAttr<WorkGroupSizeHintAttr>()) {
+ llvm::Metadata *AttrMDArgs[] = {
+ llvm::ConstantAsMetadata::get(Builder.getInt32(A->getXDim())),
+ llvm::ConstantAsMetadata::get(Builder.getInt32(A->getYDim())),
+ llvm::ConstantAsMetadata::get(Builder.getInt32(A->getZDim()))};
+ Fn->setMetadata("work_group_size_hint", llvm::MDNode::get(Context, AttrMDArgs));
+ }
+
+ if (const ReqdWorkGroupSizeAttr *A = FD->getAttr<ReqdWorkGroupSizeAttr>()) {
+ llvm::Metadata *AttrMDArgs[] = {
+ llvm::ConstantAsMetadata::get(Builder.getInt32(A->getXDim())),
+ llvm::ConstantAsMetadata::get(Builder.getInt32(A->getYDim())),
+ llvm::ConstantAsMetadata::get(Builder.getInt32(A->getZDim()))};
+ Fn->setMetadata("reqd_work_group_size", llvm::MDNode::get(Context, AttrMDArgs));
+ }
+
+ if (const OpenCLIntelReqdSubGroupSizeAttr *A =
+ FD->getAttr<OpenCLIntelReqdSubGroupSizeAttr>()) {
+ llvm::Metadata *AttrMDArgs[] = {
+ llvm::ConstantAsMetadata::get(Builder.getInt32(A->getSubGroupSize()))};
+ Fn->setMetadata("intel_reqd_sub_group_size",
+ llvm::MDNode::get(Context, AttrMDArgs));
+ }
+}
+
+/// Determine whether the function F ends with a return stmt.
+static bool endsWithReturn(const Decl* F) {
+ const Stmt *Body = nullptr;
+ if (auto *FD = dyn_cast_or_null<FunctionDecl>(F))
+ Body = FD->getBody();
+ else if (auto *OMD = dyn_cast_or_null<ObjCMethodDecl>(F))
+ Body = OMD->getBody();
+
+ if (auto *CS = dyn_cast_or_null<CompoundStmt>(Body)) {
+ auto LastStmt = CS->body_rbegin();
+ if (LastStmt != CS->body_rend())
+ return isa<ReturnStmt>(*LastStmt);
+ }
+ return false;
+}
+
+void CodeGenFunction::markAsIgnoreThreadCheckingAtRuntime(llvm::Function *Fn) {
+ if (SanOpts.has(SanitizerKind::Thread)) {
+ Fn->addFnAttr("sanitize_thread_no_checking_at_run_time");
+ Fn->removeFnAttr(llvm::Attribute::SanitizeThread);
+ }
+}
+
+/// Check if the return value of this function requires sanitization.
+bool CodeGenFunction::requiresReturnValueCheck() const {
+ return requiresReturnValueNullabilityCheck() ||
+ (SanOpts.has(SanitizerKind::ReturnsNonnullAttribute) && CurCodeDecl &&
+ CurCodeDecl->getAttr<ReturnsNonNullAttr>());
+}
+
+static bool matchesStlAllocatorFn(const Decl *D, const ASTContext &Ctx) {
+ auto *MD = dyn_cast_or_null<CXXMethodDecl>(D);
+ if (!MD || !MD->getDeclName().getAsIdentifierInfo() ||
+ !MD->getDeclName().getAsIdentifierInfo()->isStr("allocate") ||
+ (MD->getNumParams() != 1 && MD->getNumParams() != 2))
+ return false;
+
+ if (MD->parameters()[0]->getType().getCanonicalType() != Ctx.getSizeType())
+ return false;
+
+ if (MD->getNumParams() == 2) {
+ auto *PT = MD->parameters()[1]->getType()->getAs<PointerType>();
+ if (!PT || !PT->isVoidPointerType() ||
+ !PT->getPointeeType().isConstQualified())
+ return false;
+ }
+
+ return true;
+}
+
+/// Return the UBSan prologue signature for \p FD if one is available.
+static llvm::Constant *getPrologueSignature(CodeGenModule &CGM,
+ const FunctionDecl *FD) {
+ if (const auto *MD = dyn_cast<CXXMethodDecl>(FD))
+ if (!MD->isStatic())
+ return nullptr;
+ return CGM.getTargetCodeGenInfo().getUBSanFunctionSignature(CGM);
+}
+
+void CodeGenFunction::StartFunction(GlobalDecl GD, QualType RetTy,
+ llvm::Function *Fn,
+ const CGFunctionInfo &FnInfo,
+ const FunctionArgList &Args,
+ SourceLocation Loc,
+ SourceLocation StartLoc) {
+ assert(!CurFn &&
+ "Do not use a CodeGenFunction object for more than one function");
+
+ const Decl *D = GD.getDecl();
+
+ DidCallStackSave = false;
+ CurCodeDecl = D;
+ if (const auto *FD = dyn_cast_or_null<FunctionDecl>(D))
+ if (FD->usesSEHTry())
+ CurSEHParent = FD;
+ CurFuncDecl = (D ? D->getNonClosureContext() : nullptr);
+ FnRetTy = RetTy;
+ CurFn = Fn;
+ CurFnInfo = &FnInfo;
+ assert(CurFn->isDeclaration() && "Function already has body?");
+
+ // If this function has been blacklisted for any of the enabled sanitizers,
+ // disable the sanitizer for the function.
+ do {
+#define SANITIZER(NAME, ID) \
+ if (SanOpts.empty()) \
+ break; \
+ if (SanOpts.has(SanitizerKind::ID)) \
+ if (CGM.isInSanitizerBlacklist(SanitizerKind::ID, Fn, Loc)) \
+ SanOpts.set(SanitizerKind::ID, false);
+
+#include "clang/Basic/Sanitizers.def"
+#undef SANITIZER
+ } while (0);
+
+ if (D) {
+ // Apply the no_sanitize* attributes to SanOpts.
+ for (auto Attr : D->specific_attrs<NoSanitizeAttr>()) {
+ SanitizerMask mask = Attr->getMask();
+ SanOpts.Mask &= ~mask;
+ if (mask & SanitizerKind::Address)
+ SanOpts.set(SanitizerKind::KernelAddress, false);
+ if (mask & SanitizerKind::KernelAddress)
+ SanOpts.set(SanitizerKind::Address, false);
+ if (mask & SanitizerKind::HWAddress)
+ SanOpts.set(SanitizerKind::KernelHWAddress, false);
+ if (mask & SanitizerKind::KernelHWAddress)
+ SanOpts.set(SanitizerKind::HWAddress, false);
+ }
+ }
+
+ // Apply sanitizer attributes to the function.
+ if (SanOpts.hasOneOf(SanitizerKind::Address | SanitizerKind::KernelAddress))
+ Fn->addFnAttr(llvm::Attribute::SanitizeAddress);
+ if (SanOpts.hasOneOf(SanitizerKind::HWAddress | SanitizerKind::KernelHWAddress))
+ Fn->addFnAttr(llvm::Attribute::SanitizeHWAddress);
+ if (SanOpts.has(SanitizerKind::MemTag))
+ Fn->addFnAttr(llvm::Attribute::SanitizeMemTag);
+ if (SanOpts.has(SanitizerKind::Thread))
+ Fn->addFnAttr(llvm::Attribute::SanitizeThread);
+ if (SanOpts.hasOneOf(SanitizerKind::Memory | SanitizerKind::KernelMemory))
+ Fn->addFnAttr(llvm::Attribute::SanitizeMemory);
+ if (SanOpts.has(SanitizerKind::SafeStack))
+ Fn->addFnAttr(llvm::Attribute::SafeStack);
+ if (SanOpts.has(SanitizerKind::ShadowCallStack))
+ Fn->addFnAttr(llvm::Attribute::ShadowCallStack);
+
+ // Apply fuzzing attribute to the function.
+ if (SanOpts.hasOneOf(SanitizerKind::Fuzzer | SanitizerKind::FuzzerNoLink))
+ Fn->addFnAttr(llvm::Attribute::OptForFuzzing);
+
+ // Ignore TSan memory acesses from within ObjC/ObjC++ dealloc, initialize,
+ // .cxx_destruct, __destroy_helper_block_ and all of their calees at run time.
+ if (SanOpts.has(SanitizerKind::Thread)) {
+ if (const auto *OMD = dyn_cast_or_null<ObjCMethodDecl>(D)) {
+ IdentifierInfo *II = OMD->getSelector().getIdentifierInfoForSlot(0);
+ if (OMD->getMethodFamily() == OMF_dealloc ||
+ OMD->getMethodFamily() == OMF_initialize ||
+ (OMD->getSelector().isUnarySelector() && II->isStr(".cxx_destruct"))) {
+ markAsIgnoreThreadCheckingAtRuntime(Fn);
+ }
+ }
+ }
+
+ // Ignore unrelated casts in STL allocate() since the allocator must cast
+ // from void* to T* before object initialization completes. Don't match on the
+ // namespace because not all allocators are in std::
+ if (D && SanOpts.has(SanitizerKind::CFIUnrelatedCast)) {
+ if (matchesStlAllocatorFn(D, getContext()))
+ SanOpts.Mask &= ~SanitizerKind::CFIUnrelatedCast;
+ }
+
+ // Ignore null checks in coroutine functions since the coroutines passes
+ // are not aware of how to move the extra UBSan instructions across the split
+ // coroutine boundaries.
+ if (D && SanOpts.has(SanitizerKind::Null))
+ if (const auto *FD = dyn_cast<FunctionDecl>(D))
+ if (FD->getBody() &&
+ FD->getBody()->getStmtClass() == Stmt::CoroutineBodyStmtClass)
+ SanOpts.Mask &= ~SanitizerKind::Null;
+
+ if (D) {
+ // Apply xray attributes to the function (as a string, for now)
+ if (const auto *XRayAttr = D->getAttr<XRayInstrumentAttr>()) {
+ if (CGM.getCodeGenOpts().XRayInstrumentationBundle.has(
+ XRayInstrKind::Function)) {
+ if (XRayAttr->alwaysXRayInstrument() && ShouldXRayInstrumentFunction())
+ Fn->addFnAttr("function-instrument", "xray-always");
+ if (XRayAttr->neverXRayInstrument())
+ Fn->addFnAttr("function-instrument", "xray-never");
+ if (const auto *LogArgs = D->getAttr<XRayLogArgsAttr>())
+ if (ShouldXRayInstrumentFunction())
+ Fn->addFnAttr("xray-log-args",
+ llvm::utostr(LogArgs->getArgumentCount()));
+ }
+ } else {
+ if (ShouldXRayInstrumentFunction() && !CGM.imbueXRayAttrs(Fn, Loc))
+ Fn->addFnAttr(
+ "xray-instruction-threshold",
+ llvm::itostr(CGM.getCodeGenOpts().XRayInstructionThreshold));
+ }
+
+ unsigned Count, Offset;
+ if (const auto *Attr = D->getAttr<PatchableFunctionEntryAttr>()) {
+ Count = Attr->getCount();
+ Offset = Attr->getOffset();
+ } else {
+ Count = CGM.getCodeGenOpts().PatchableFunctionEntryCount;
+ Offset = CGM.getCodeGenOpts().PatchableFunctionEntryOffset;
+ }
+ if (Count && Offset <= Count) {
+ Fn->addFnAttr("patchable-function-entry", std::to_string(Count - Offset));
+ if (Offset)
+ Fn->addFnAttr("patchable-function-prefix", std::to_string(Offset));
+ }
+ }
+
+ // Add no-jump-tables value.
+ Fn->addFnAttr("no-jump-tables",
+ llvm::toStringRef(CGM.getCodeGenOpts().NoUseJumpTables));
+
+ // Add no-inline-line-tables value.
+ if (CGM.getCodeGenOpts().NoInlineLineTables)
+ Fn->addFnAttr("no-inline-line-tables");
+
+ // Add profile-sample-accurate value.
+ if (CGM.getCodeGenOpts().ProfileSampleAccurate)
+ Fn->addFnAttr("profile-sample-accurate");
+
+ if (D && D->hasAttr<CFICanonicalJumpTableAttr>())
+ Fn->addFnAttr("cfi-canonical-jump-table");
+
+ if (getLangOpts().OpenCL) {
+ // Add metadata for a kernel function.
+ if (const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(D))
+ EmitOpenCLKernelMetadata(FD, Fn);
+ }
+
+ // If we are checking function types, emit a function type signature as
+ // prologue data.
+ if (getLangOpts().CPlusPlus && SanOpts.has(SanitizerKind::Function)) {
+ if (const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(D)) {
+ if (llvm::Constant *PrologueSig = getPrologueSignature(CGM, FD)) {
+ // Remove any (C++17) exception specifications, to allow calling e.g. a
+ // noexcept function through a non-noexcept pointer.
+ auto ProtoTy =
+ getContext().getFunctionTypeWithExceptionSpec(FD->getType(),
+ EST_None);
+ llvm::Constant *FTRTTIConst =
+ CGM.GetAddrOfRTTIDescriptor(ProtoTy, /*ForEH=*/true);
+ llvm::Constant *FTRTTIConstEncoded =
+ EncodeAddrForUseInPrologue(Fn, FTRTTIConst);
+ llvm::Constant *PrologueStructElems[] = {PrologueSig,
+ FTRTTIConstEncoded};
+ llvm::Constant *PrologueStructConst =
+ llvm::ConstantStruct::getAnon(PrologueStructElems, /*Packed=*/true);
+ Fn->setPrologueData(PrologueStructConst);
+ }
+ }
+ }
+
+ // If we're checking nullability, we need to know whether we can check the
+ // return value. Initialize the flag to 'true' and refine it in EmitParmDecl.
+ if (SanOpts.has(SanitizerKind::NullabilityReturn)) {
+ auto Nullability = FnRetTy->getNullability(getContext());
+ if (Nullability && *Nullability == NullabilityKind::NonNull) {
+ if (!(SanOpts.has(SanitizerKind::ReturnsNonnullAttribute) &&
+ CurCodeDecl && CurCodeDecl->getAttr<ReturnsNonNullAttr>()))
+ RetValNullabilityPrecondition =
+ llvm::ConstantInt::getTrue(getLLVMContext());
+ }
+ }
+
+ // If we're in C++ mode and the function name is "main", it is guaranteed
+ // to be norecurse by the standard (3.6.1.3 "The function main shall not be
+ // used within a program").
+ if (getLangOpts().CPlusPlus)
+ if (const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(D))
+ if (FD->isMain())
+ Fn->addFnAttr(llvm::Attribute::NoRecurse);
+
+ if (const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(D))
+ if (FD->usesFPIntrin())
+ Fn->addFnAttr(llvm::Attribute::StrictFP);
+
+ // If a custom alignment is used, force realigning to this alignment on
+ // any main function which certainly will need it.
+ if (const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(D))
+ if ((FD->isMain() || FD->isMSVCRTEntryPoint()) &&
+ CGM.getCodeGenOpts().StackAlignment)
+ Fn->addFnAttr("stackrealign");
+
+ llvm::BasicBlock *EntryBB = createBasicBlock("entry", CurFn);
+
+ // Create a marker to make it easy to insert allocas into the entryblock
+ // later. Don't create this with the builder, because we don't want it
+ // folded.
+ llvm::Value *Undef = llvm::UndefValue::get(Int32Ty);
+ AllocaInsertPt = new llvm::BitCastInst(Undef, Int32Ty, "allocapt", EntryBB);
+
+ ReturnBlock = getJumpDestInCurrentScope("return");
+
+ Builder.SetInsertPoint(EntryBB);
+
+ // If we're checking the return value, allocate space for a pointer to a
+ // precise source location of the checked return statement.
+ if (requiresReturnValueCheck()) {
+ ReturnLocation = CreateDefaultAlignTempAlloca(Int8PtrTy, "return.sloc.ptr");
+ InitTempAlloca(ReturnLocation, llvm::ConstantPointerNull::get(Int8PtrTy));
+ }
+
+ // Emit subprogram debug descriptor.
+ if (CGDebugInfo *DI = getDebugInfo()) {
+ // Reconstruct the type from the argument list so that implicit parameters,
+ // such as 'this' and 'vtt', show up in the debug info. Preserve the calling
+ // convention.
+ CallingConv CC = CallingConv::CC_C;
+ if (auto *FD = dyn_cast_or_null<FunctionDecl>(D))
+ if (const auto *SrcFnTy = FD->getType()->getAs<FunctionType>())
+ CC = SrcFnTy->getCallConv();
+ SmallVector<QualType, 16> ArgTypes;
+ for (const VarDecl *VD : Args)
+ ArgTypes.push_back(VD->getType());
+ QualType FnType = getContext().getFunctionType(
+ RetTy, ArgTypes, FunctionProtoType::ExtProtoInfo(CC));
+ DI->EmitFunctionStart(GD, Loc, StartLoc, FnType, CurFn, CurFuncIsThunk,
+ Builder);
+ }
+
+ if (ShouldInstrumentFunction()) {
+ if (CGM.getCodeGenOpts().InstrumentFunctions)
+ CurFn->addFnAttr("instrument-function-entry", "__cyg_profile_func_enter");
+ if (CGM.getCodeGenOpts().InstrumentFunctionsAfterInlining)
+ CurFn->addFnAttr("instrument-function-entry-inlined",
+ "__cyg_profile_func_enter");
+ if (CGM.getCodeGenOpts().InstrumentFunctionEntryBare)
+ CurFn->addFnAttr("instrument-function-entry-inlined",
+ "__cyg_profile_func_enter_bare");
+ }
+
+ // Since emitting the mcount call here impacts optimizations such as function
+ // inlining, we just add an attribute to insert a mcount call in backend.
+ // The attribute "counting-function" is set to mcount function name which is
+ // architecture dependent.
+ if (CGM.getCodeGenOpts().InstrumentForProfiling) {
+ // Calls to fentry/mcount should not be generated if function has
+ // the no_instrument_function attribute.
+ if (!CurFuncDecl || !CurFuncDecl->hasAttr<NoInstrumentFunctionAttr>()) {
+ if (CGM.getCodeGenOpts().CallFEntry)
+ Fn->addFnAttr("fentry-call", "true");
+ else {
+ Fn->addFnAttr("instrument-function-entry-inlined",
+ getTarget().getMCountName());
+ }
+ if (CGM.getCodeGenOpts().MNopMCount) {
+ if (!CGM.getCodeGenOpts().CallFEntry)
+ CGM.getDiags().Report(diag::err_opt_not_valid_without_opt)
+ << "-mnop-mcount" << "-mfentry";
+ Fn->addFnAttr("mnop-mcount");
+ }
+
+ if (CGM.getCodeGenOpts().RecordMCount) {
+ if (!CGM.getCodeGenOpts().CallFEntry)
+ CGM.getDiags().Report(diag::err_opt_not_valid_without_opt)
+ << "-mrecord-mcount" << "-mfentry";
+ Fn->addFnAttr("mrecord-mcount");
+ }
+ }
+ }
+
+ if (CGM.getCodeGenOpts().PackedStack) {
+ if (getContext().getTargetInfo().getTriple().getArch() !=
+ llvm::Triple::systemz)
+ CGM.getDiags().Report(diag::err_opt_not_valid_on_target)
+ << "-mpacked-stack";
+ Fn->addFnAttr("packed-stack");
+ }
+
+ if (RetTy->isVoidType()) {
+ // Void type; nothing to return.
+ ReturnValue = Address::invalid();
+
+ // Count the implicit return.
+ if (!endsWithReturn(D))
+ ++NumReturnExprs;
+ } else if (CurFnInfo->getReturnInfo().getKind() == ABIArgInfo::Indirect) {
+ // Indirect return; emit returned value directly into sret slot.
+ // This reduces code size, and affects correctness in C++.
+ auto AI = CurFn->arg_begin();
+ if (CurFnInfo->getReturnInfo().isSRetAfterThis())
+ ++AI;
+ ReturnValue = Address(&*AI, CurFnInfo->getReturnInfo().getIndirectAlign());
+ if (!CurFnInfo->getReturnInfo().getIndirectByVal()) {
+ ReturnValuePointer =
+ CreateDefaultAlignTempAlloca(Int8PtrTy, "result.ptr");
+ Builder.CreateStore(Builder.CreatePointerBitCastOrAddrSpaceCast(
+ ReturnValue.getPointer(), Int8PtrTy),
+ ReturnValuePointer);
+ }
+ } else if (CurFnInfo->getReturnInfo().getKind() == ABIArgInfo::InAlloca &&
+ !hasScalarEvaluationKind(CurFnInfo->getReturnType())) {
+ // Load the sret pointer from the argument struct and return into that.
+ unsigned Idx = CurFnInfo->getReturnInfo().getInAllocaFieldIndex();
+ llvm::Function::arg_iterator EI = CurFn->arg_end();
+ --EI;
+ llvm::Value *Addr = Builder.CreateStructGEP(nullptr, &*EI, Idx);
+ ReturnValuePointer = Address(Addr, getPointerAlign());
+ Addr = Builder.CreateAlignedLoad(Addr, getPointerAlign(), "agg.result");
+ ReturnValue = Address(Addr, getNaturalTypeAlignment(RetTy));
+ } else {
+ ReturnValue = CreateIRTemp(RetTy, "retval");
+
+ // Tell the epilog emitter to autorelease the result. We do this
+ // now so that various specialized functions can suppress it
+ // during their IR-generation.
+ if (getLangOpts().ObjCAutoRefCount &&
+ !CurFnInfo->isReturnsRetained() &&
+ RetTy->isObjCRetainableType())
+ AutoreleaseResult = true;
+ }
+
+ EmitStartEHSpec(CurCodeDecl);
+
+ PrologueCleanupDepth = EHStack.stable_begin();
+
+ // Emit OpenMP specific initialization of the device functions.
+ if (getLangOpts().OpenMP && CurCodeDecl)
+ CGM.getOpenMPRuntime().emitFunctionProlog(*this, CurCodeDecl);
+
+ EmitFunctionProlog(*CurFnInfo, CurFn, Args);
+
+ if (D && isa<CXXMethodDecl>(D) && cast<CXXMethodDecl>(D)->isInstance()) {
+ CGM.getCXXABI().EmitInstanceFunctionProlog(*this);
+ const CXXMethodDecl *MD = cast<CXXMethodDecl>(D);
+ if (MD->getParent()->isLambda() &&
+ MD->getOverloadedOperator() == OO_Call) {
+ // We're in a lambda; figure out the captures.
+ MD->getParent()->getCaptureFields(LambdaCaptureFields,
+ LambdaThisCaptureField);
+ if (LambdaThisCaptureField) {
+ // If the lambda captures the object referred to by '*this' - either by
+ // value or by reference, make sure CXXThisValue points to the correct
+ // object.
+
+ // Get the lvalue for the field (which is a copy of the enclosing object
+ // or contains the address of the enclosing object).
+ LValue ThisFieldLValue = EmitLValueForLambdaField(LambdaThisCaptureField);
+ if (!LambdaThisCaptureField->getType()->isPointerType()) {
+ // If the enclosing object was captured by value, just use its address.
+ CXXThisValue = ThisFieldLValue.getAddress(*this).getPointer();
+ } else {
+ // Load the lvalue pointed to by the field, since '*this' was captured
+ // by reference.
+ CXXThisValue =
+ EmitLoadOfLValue(ThisFieldLValue, SourceLocation()).getScalarVal();
+ }
+ }
+ for (auto *FD : MD->getParent()->fields()) {
+ if (FD->hasCapturedVLAType()) {
+ auto *ExprArg = EmitLoadOfLValue(EmitLValueForLambdaField(FD),
+ SourceLocation()).getScalarVal();
+ auto VAT = FD->getCapturedVLAType();
+ VLASizeMap[VAT->getSizeExpr()] = ExprArg;
+ }
+ }
+ } else {
+ // Not in a lambda; just use 'this' from the method.
+ // FIXME: Should we generate a new load for each use of 'this'? The
+ // fast register allocator would be happier...
+ CXXThisValue = CXXABIThisValue;
+ }
+
+ // Check the 'this' pointer once per function, if it's available.
+ if (CXXABIThisValue) {
+ SanitizerSet SkippedChecks;
+ SkippedChecks.set(SanitizerKind::ObjectSize, true);
+ QualType ThisTy = MD->getThisType();
+
+ // If this is the call operator of a lambda with no capture-default, it
+ // may have a static invoker function, which may call this operator with
+ // a null 'this' pointer.
+ if (isLambdaCallOperator(MD) &&
+ MD->getParent()->getLambdaCaptureDefault() == LCD_None)
+ SkippedChecks.set(SanitizerKind::Null, true);
+
+ EmitTypeCheck(isa<CXXConstructorDecl>(MD) ? TCK_ConstructorCall
+ : TCK_MemberCall,
+ Loc, CXXABIThisValue, ThisTy,
+ getContext().getTypeAlignInChars(ThisTy->getPointeeType()),
+ SkippedChecks);
+ }
+ }
+
+ // If any of the arguments have a variably modified type, make sure to
+ // emit the type size.
+ for (FunctionArgList::const_iterator i = Args.begin(), e = Args.end();
+ i != e; ++i) {
+ const VarDecl *VD = *i;
+
+ // Dig out the type as written from ParmVarDecls; it's unclear whether
+ // the standard (C99 6.9.1p10) requires this, but we're following the
+ // precedent set by gcc.
+ QualType Ty;
+ if (const ParmVarDecl *PVD = dyn_cast<ParmVarDecl>(VD))
+ Ty = PVD->getOriginalType();
+ else
+ Ty = VD->getType();
+
+ if (Ty->isVariablyModifiedType())
+ EmitVariablyModifiedType(Ty);
+ }
+ // Emit a location at the end of the prologue.
+ if (CGDebugInfo *DI = getDebugInfo())
+ DI->EmitLocation(Builder, StartLoc);
+
+ // TODO: Do we need to handle this in two places like we do with
+ // target-features/target-cpu?
+ if (CurFuncDecl)
+ if (const auto *VecWidth = CurFuncDecl->getAttr<MinVectorWidthAttr>())
+ LargestVectorWidth = VecWidth->getVectorWidth();
+}
+
+void CodeGenFunction::EmitFunctionBody(const Stmt *Body) {
+ incrementProfileCounter(Body);
+ if (const CompoundStmt *S = dyn_cast<CompoundStmt>(Body))
+ EmitCompoundStmtWithoutScope(*S);
+ else
+ EmitStmt(Body);
+}
+
+/// When instrumenting to collect profile data, the counts for some blocks
+/// such as switch cases need to not include the fall-through counts, so
+/// emit a branch around the instrumentation code. When not instrumenting,
+/// this just calls EmitBlock().
+void CodeGenFunction::EmitBlockWithFallThrough(llvm::BasicBlock *BB,
+ const Stmt *S) {
+ llvm::BasicBlock *SkipCountBB = nullptr;
+ if (HaveInsertPoint() && CGM.getCodeGenOpts().hasProfileClangInstr()) {
+ // When instrumenting for profiling, the fallthrough to certain
+ // statements needs to skip over the instrumentation code so that we
+ // get an accurate count.
+ SkipCountBB = createBasicBlock("skipcount");
+ EmitBranch(SkipCountBB);
+ }
+ EmitBlock(BB);
+ uint64_t CurrentCount = getCurrentProfileCount();
+ incrementProfileCounter(S);
+ setCurrentProfileCount(getCurrentProfileCount() + CurrentCount);
+ if (SkipCountBB)
+ EmitBlock(SkipCountBB);
+}
+
+/// Tries to mark the given function nounwind based on the
+/// non-existence of any throwing calls within it. We believe this is
+/// lightweight enough to do at -O0.
+static void TryMarkNoThrow(llvm::Function *F) {
+ // LLVM treats 'nounwind' on a function as part of the type, so we
+ // can't do this on functions that can be overwritten.
+ if (F->isInterposable()) return;
+
+ for (llvm::BasicBlock &BB : *F)
+ for (llvm::Instruction &I : BB)
+ if (I.mayThrow())
+ return;
+
+ F->setDoesNotThrow();
+}
+
+QualType CodeGenFunction::BuildFunctionArgList(GlobalDecl GD,
+ FunctionArgList &Args) {
+ const FunctionDecl *FD = cast<FunctionDecl>(GD.getDecl());
+ QualType ResTy = FD->getReturnType();
+
+ const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD);
+ if (MD && MD->isInstance()) {
+ if (CGM.getCXXABI().HasThisReturn(GD))
+ ResTy = MD->getThisType();
+ else if (CGM.getCXXABI().hasMostDerivedReturn(GD))
+ ResTy = CGM.getContext().VoidPtrTy;
+ CGM.getCXXABI().buildThisParam(*this, Args);
+ }
+
+ // The base version of an inheriting constructor whose constructed base is a
+ // virtual base is not passed any arguments (because it doesn't actually call
+ // the inherited constructor).
+ bool PassedParams = true;
+ if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(FD))
+ if (auto Inherited = CD->getInheritedConstructor())
+ PassedParams =
+ getTypes().inheritingCtorHasParams(Inherited, GD.getCtorType());
+
+ if (PassedParams) {
+ for (auto *Param : FD->parameters()) {
+ Args.push_back(Param);
+ if (!Param->hasAttr<PassObjectSizeAttr>())
+ continue;
+
+ auto *Implicit = ImplicitParamDecl::Create(
+ getContext(), Param->getDeclContext(), Param->getLocation(),
+ /*Id=*/nullptr, getContext().getSizeType(), ImplicitParamDecl::Other);
+ SizeArguments[Param] = Implicit;
+ Args.push_back(Implicit);
+ }
+ }
+
+ if (MD && (isa<CXXConstructorDecl>(MD) || isa<CXXDestructorDecl>(MD)))
+ CGM.getCXXABI().addImplicitStructorParams(*this, ResTy, Args);
+
+ return ResTy;
+}
+
+static bool
+shouldUseUndefinedBehaviorReturnOptimization(const FunctionDecl *FD,
+ const ASTContext &Context) {
+ QualType T = FD->getReturnType();
+ // Avoid the optimization for functions that return a record type with a
+ // trivial destructor or another trivially copyable type.
+ if (const RecordType *RT = T.getCanonicalType()->getAs<RecordType>()) {
+ if (const auto *ClassDecl = dyn_cast<CXXRecordDecl>(RT->getDecl()))
+ return !ClassDecl->hasTrivialDestructor();
+ }
+ return !T.isTriviallyCopyableType(Context);
+}
+
+void CodeGenFunction::GenerateCode(GlobalDecl GD, llvm::Function *Fn,
+ const CGFunctionInfo &FnInfo) {
+ const FunctionDecl *FD = cast<FunctionDecl>(GD.getDecl());
+ CurGD = GD;
+
+ FunctionArgList Args;
+ QualType ResTy = BuildFunctionArgList(GD, Args);
+
+ // Check if we should generate debug info for this function.
+ if (FD->hasAttr<NoDebugAttr>())
+ DebugInfo = nullptr; // disable debug info indefinitely for this function
+
+ // The function might not have a body if we're generating thunks for a
+ // function declaration.
+ SourceRange BodyRange;
+ if (Stmt *Body = FD->getBody())
+ BodyRange = Body->getSourceRange();
+ else
+ BodyRange = FD->getLocation();
+ CurEHLocation = BodyRange.getEnd();
+
+ // Use the location of the start of the function to determine where
+ // the function definition is located. By default use the location
+ // of the declaration as the location for the subprogram. A function
+ // may lack a declaration in the source code if it is created by code
+ // gen. (examples: _GLOBAL__I_a, __cxx_global_array_dtor, thunk).
+ SourceLocation Loc = FD->getLocation();
+
+ // If this is a function specialization then use the pattern body
+ // as the location for the function.
+ if (const FunctionDecl *SpecDecl = FD->getTemplateInstantiationPattern())
+ if (SpecDecl->hasBody(SpecDecl))
+ Loc = SpecDecl->getLocation();
+
+ Stmt *Body = FD->getBody();
+
+ // Initialize helper which will detect jumps which can cause invalid lifetime
+ // markers.
+ if (Body && ShouldEmitLifetimeMarkers)
+ Bypasses.Init(Body);
+
+ // Emit the standard function prologue.
+ StartFunction(GD, ResTy, Fn, FnInfo, Args, Loc, BodyRange.getBegin());
+
+ // Generate the body of the function.
+ PGO.assignRegionCounters(GD, CurFn);
+ if (isa<CXXDestructorDecl>(FD))
+ EmitDestructorBody(Args);
+ else if (isa<CXXConstructorDecl>(FD))
+ EmitConstructorBody(Args);
+ else if (getLangOpts().CUDA &&
+ !getLangOpts().CUDAIsDevice &&
+ FD->hasAttr<CUDAGlobalAttr>())
+ CGM.getCUDARuntime().emitDeviceStub(*this, Args);
+ else if (isa<CXXMethodDecl>(FD) &&
+ cast<CXXMethodDecl>(FD)->isLambdaStaticInvoker()) {
+ // The lambda static invoker function is special, because it forwards or
+ // clones the body of the function call operator (but is actually static).
+ EmitLambdaStaticInvokeBody(cast<CXXMethodDecl>(FD));
+ } else if (FD->isDefaulted() && isa<CXXMethodDecl>(FD) &&
+ (cast<CXXMethodDecl>(FD)->isCopyAssignmentOperator() ||
+ cast<CXXMethodDecl>(FD)->isMoveAssignmentOperator())) {
+ // Implicit copy-assignment gets the same special treatment as implicit
+ // copy-constructors.
+ emitImplicitAssignmentOperatorBody(Args);
+ } else if (Body) {
+ EmitFunctionBody(Body);
+ } else
+ llvm_unreachable("no definition for emitted function");
+
+ // C++11 [stmt.return]p2:
+ // Flowing off the end of a function [...] results in undefined behavior in
+ // a value-returning function.
+ // C11 6.9.1p12:
+ // If the '}' that terminates a function is reached, and the value of the
+ // function call is used by the caller, the behavior is undefined.
+ if (getLangOpts().CPlusPlus && !FD->hasImplicitReturnZero() && !SawAsmBlock &&
+ !FD->getReturnType()->isVoidType() && Builder.GetInsertBlock()) {
+ bool ShouldEmitUnreachable =
+ CGM.getCodeGenOpts().StrictReturn ||
+ shouldUseUndefinedBehaviorReturnOptimization(FD, getContext());
+ if (SanOpts.has(SanitizerKind::Return)) {
+ SanitizerScope SanScope(this);
+ llvm::Value *IsFalse = Builder.getFalse();
+ EmitCheck(std::make_pair(IsFalse, SanitizerKind::Return),
+ SanitizerHandler::MissingReturn,
+ EmitCheckSourceLocation(FD->getLocation()), None);
+ } else if (ShouldEmitUnreachable) {
+ if (CGM.getCodeGenOpts().OptimizationLevel == 0)
+ EmitTrapCall(llvm::Intrinsic::trap);
+ }
+ if (SanOpts.has(SanitizerKind::Return) || ShouldEmitUnreachable) {
+ Builder.CreateUnreachable();
+ Builder.ClearInsertionPoint();
+ }
+ }
+
+ // Emit the standard function epilogue.
+ FinishFunction(BodyRange.getEnd());
+
+ // If we haven't marked the function nothrow through other means, do
+ // a quick pass now to see if we can.
+ if (!CurFn->doesNotThrow())
+ TryMarkNoThrow(CurFn);
+}
+
+/// ContainsLabel - Return true if the statement contains a label in it. If
+/// this statement is not executed normally, it not containing a label means
+/// that we can just remove the code.
+bool CodeGenFunction::ContainsLabel(const Stmt *S, bool IgnoreCaseStmts) {
+ // Null statement, not a label!
+ if (!S) return false;
+
+ // If this is a label, we have to emit the code, consider something like:
+ // if (0) { ... foo: bar(); } goto foo;
+ //
+ // TODO: If anyone cared, we could track __label__'s, since we know that you
+ // can't jump to one from outside their declared region.
+ if (isa<LabelStmt>(S))
+ return true;
+
+ // If this is a case/default statement, and we haven't seen a switch, we have
+ // to emit the code.
+ if (isa<SwitchCase>(S) && !IgnoreCaseStmts)
+ return true;
+
+ // If this is a switch statement, we want to ignore cases below it.
+ if (isa<SwitchStmt>(S))
+ IgnoreCaseStmts = true;
+
+ // Scan subexpressions for verboten labels.
+ for (const Stmt *SubStmt : S->children())
+ if (ContainsLabel(SubStmt, IgnoreCaseStmts))
+ return true;
+
+ return false;
+}
+
+/// containsBreak - Return true if the statement contains a break out of it.
+/// If the statement (recursively) contains a switch or loop with a break
+/// inside of it, this is fine.
+bool CodeGenFunction::containsBreak(const Stmt *S) {
+ // Null statement, not a label!
+ if (!S) return false;
+
+ // If this is a switch or loop that defines its own break scope, then we can
+ // include it and anything inside of it.
+ if (isa<SwitchStmt>(S) || isa<WhileStmt>(S) || isa<DoStmt>(S) ||
+ isa<ForStmt>(S))
+ return false;
+
+ if (isa<BreakStmt>(S))
+ return true;
+
+ // Scan subexpressions for verboten breaks.
+ for (const Stmt *SubStmt : S->children())
+ if (containsBreak(SubStmt))
+ return true;
+
+ return false;
+}
+
+bool CodeGenFunction::mightAddDeclToScope(const Stmt *S) {
+ if (!S) return false;
+
+ // Some statement kinds add a scope and thus never add a decl to the current
+ // scope. Note, this list is longer than the list of statements that might
+ // have an unscoped decl nested within them, but this way is conservatively
+ // correct even if more statement kinds are added.
+ if (isa<IfStmt>(S) || isa<SwitchStmt>(S) || isa<WhileStmt>(S) ||
+ isa<DoStmt>(S) || isa<ForStmt>(S) || isa<CompoundStmt>(S) ||
+ isa<CXXForRangeStmt>(S) || isa<CXXTryStmt>(S) ||
+ isa<ObjCForCollectionStmt>(S) || isa<ObjCAtTryStmt>(S))
+ return false;
+
+ if (isa<DeclStmt>(S))
+ return true;
+
+ for (const Stmt *SubStmt : S->children())
+ if (mightAddDeclToScope(SubStmt))
+ return true;
+
+ return false;
+}
+
+/// ConstantFoldsToSimpleInteger - If the specified expression does not fold
+/// to a constant, or if it does but contains a label, return false. If it
+/// constant folds return true and set the boolean result in Result.
+bool CodeGenFunction::ConstantFoldsToSimpleInteger(const Expr *Cond,
+ bool &ResultBool,
+ bool AllowLabels) {
+ llvm::APSInt ResultInt;
+ if (!ConstantFoldsToSimpleInteger(Cond, ResultInt, AllowLabels))
+ return false;
+
+ ResultBool = ResultInt.getBoolValue();
+ return true;
+}
+
+/// ConstantFoldsToSimpleInteger - If the specified expression does not fold
+/// to a constant, or if it does but contains a label, return false. If it
+/// constant folds return true and set the folded value.
+bool CodeGenFunction::ConstantFoldsToSimpleInteger(const Expr *Cond,
+ llvm::APSInt &ResultInt,
+ bool AllowLabels) {
+ // FIXME: Rename and handle conversion of other evaluatable things
+ // to bool.
+ Expr::EvalResult Result;
+ if (!Cond->EvaluateAsInt(Result, getContext()))
+ return false; // Not foldable, not integer or not fully evaluatable.
+
+ llvm::APSInt Int = Result.Val.getInt();
+ if (!AllowLabels && CodeGenFunction::ContainsLabel(Cond))
+ return false; // Contains a label.
+
+ ResultInt = Int;
+ return true;
+}
+
+
+
+/// EmitBranchOnBoolExpr - Emit a branch on a boolean condition (e.g. for an if
+/// statement) to the specified blocks. Based on the condition, this might try
+/// to simplify the codegen of the conditional based on the branch.
+///
+void CodeGenFunction::EmitBranchOnBoolExpr(const Expr *Cond,
+ llvm::BasicBlock *TrueBlock,
+ llvm::BasicBlock *FalseBlock,
+ uint64_t TrueCount) {
+ Cond = Cond->IgnoreParens();
+
+ if (const BinaryOperator *CondBOp = dyn_cast<BinaryOperator>(Cond)) {
+
+ // Handle X && Y in a condition.
+ if (CondBOp->getOpcode() == BO_LAnd) {
+ // If we have "1 && X", simplify the code. "0 && X" would have constant
+ // folded if the case was simple enough.
+ bool ConstantBool = false;
+ if (ConstantFoldsToSimpleInteger(CondBOp->getLHS(), ConstantBool) &&
+ ConstantBool) {
+ // br(1 && X) -> br(X).
+ incrementProfileCounter(CondBOp);
+ return EmitBranchOnBoolExpr(CondBOp->getRHS(), TrueBlock, FalseBlock,
+ TrueCount);
+ }
+
+ // If we have "X && 1", simplify the code to use an uncond branch.
+ // "X && 0" would have been constant folded to 0.
+ if (ConstantFoldsToSimpleInteger(CondBOp->getRHS(), ConstantBool) &&
+ ConstantBool) {
+ // br(X && 1) -> br(X).
+ return EmitBranchOnBoolExpr(CondBOp->getLHS(), TrueBlock, FalseBlock,
+ TrueCount);
+ }
+
+ // Emit the LHS as a conditional. If the LHS conditional is false, we
+ // want to jump to the FalseBlock.
+ llvm::BasicBlock *LHSTrue = createBasicBlock("land.lhs.true");
+ // The counter tells us how often we evaluate RHS, and all of TrueCount
+ // can be propagated to that branch.
+ uint64_t RHSCount = getProfileCount(CondBOp->getRHS());
+
+ ConditionalEvaluation eval(*this);
+ {
+ ApplyDebugLocation DL(*this, Cond);
+ EmitBranchOnBoolExpr(CondBOp->getLHS(), LHSTrue, FalseBlock, RHSCount);
+ EmitBlock(LHSTrue);
+ }
+
+ incrementProfileCounter(CondBOp);
+ setCurrentProfileCount(getProfileCount(CondBOp->getRHS()));
+
+ // Any temporaries created here are conditional.
+ eval.begin(*this);
+ EmitBranchOnBoolExpr(CondBOp->getRHS(), TrueBlock, FalseBlock, TrueCount);
+ eval.end(*this);
+
+ return;
+ }
+
+ if (CondBOp->getOpcode() == BO_LOr) {
+ // If we have "0 || X", simplify the code. "1 || X" would have constant
+ // folded if the case was simple enough.
+ bool ConstantBool = false;
+ if (ConstantFoldsToSimpleInteger(CondBOp->getLHS(), ConstantBool) &&
+ !ConstantBool) {
+ // br(0 || X) -> br(X).
+ incrementProfileCounter(CondBOp);
+ return EmitBranchOnBoolExpr(CondBOp->getRHS(), TrueBlock, FalseBlock,
+ TrueCount);
+ }
+
+ // If we have "X || 0", simplify the code to use an uncond branch.
+ // "X || 1" would have been constant folded to 1.
+ if (ConstantFoldsToSimpleInteger(CondBOp->getRHS(), ConstantBool) &&
+ !ConstantBool) {
+ // br(X || 0) -> br(X).
+ return EmitBranchOnBoolExpr(CondBOp->getLHS(), TrueBlock, FalseBlock,
+ TrueCount);
+ }
+
+ // Emit the LHS as a conditional. If the LHS conditional is true, we
+ // want to jump to the TrueBlock.
+ llvm::BasicBlock *LHSFalse = createBasicBlock("lor.lhs.false");
+ // We have the count for entry to the RHS and for the whole expression
+ // being true, so we can divy up True count between the short circuit and
+ // the RHS.
+ uint64_t LHSCount =
+ getCurrentProfileCount() - getProfileCount(CondBOp->getRHS());
+ uint64_t RHSCount = TrueCount - LHSCount;
+
+ ConditionalEvaluation eval(*this);
+ {
+ ApplyDebugLocation DL(*this, Cond);
+ EmitBranchOnBoolExpr(CondBOp->getLHS(), TrueBlock, LHSFalse, LHSCount);
+ EmitBlock(LHSFalse);
+ }
+
+ incrementProfileCounter(CondBOp);
+ setCurrentProfileCount(getProfileCount(CondBOp->getRHS()));
+
+ // Any temporaries created here are conditional.
+ eval.begin(*this);
+ EmitBranchOnBoolExpr(CondBOp->getRHS(), TrueBlock, FalseBlock, RHSCount);
+
+ eval.end(*this);
+
+ return;
+ }
+ }
+
+ if (const UnaryOperator *CondUOp = dyn_cast<UnaryOperator>(Cond)) {
+ // br(!x, t, f) -> br(x, f, t)
+ if (CondUOp->getOpcode() == UO_LNot) {
+ // Negate the count.
+ uint64_t FalseCount = getCurrentProfileCount() - TrueCount;
+ // Negate the condition and swap the destination blocks.
+ return EmitBranchOnBoolExpr(CondUOp->getSubExpr(), FalseBlock, TrueBlock,
+ FalseCount);
+ }
+ }
+
+ if (const ConditionalOperator *CondOp = dyn_cast<ConditionalOperator>(Cond)) {
+ // br(c ? x : y, t, f) -> br(c, br(x, t, f), br(y, t, f))
+ llvm::BasicBlock *LHSBlock = createBasicBlock("cond.true");
+ llvm::BasicBlock *RHSBlock = createBasicBlock("cond.false");
+
+ ConditionalEvaluation cond(*this);
+ EmitBranchOnBoolExpr(CondOp->getCond(), LHSBlock, RHSBlock,
+ getProfileCount(CondOp));
+
+ // When computing PGO branch weights, we only know the overall count for
+ // the true block. This code is essentially doing tail duplication of the
+ // naive code-gen, introducing new edges for which counts are not
+ // available. Divide the counts proportionally between the LHS and RHS of
+ // the conditional operator.
+ uint64_t LHSScaledTrueCount = 0;
+ if (TrueCount) {
+ double LHSRatio =
+ getProfileCount(CondOp) / (double)getCurrentProfileCount();
+ LHSScaledTrueCount = TrueCount * LHSRatio;
+ }
+
+ cond.begin(*this);
+ EmitBlock(LHSBlock);
+ incrementProfileCounter(CondOp);
+ {
+ ApplyDebugLocation DL(*this, Cond);
+ EmitBranchOnBoolExpr(CondOp->getLHS(), TrueBlock, FalseBlock,
+ LHSScaledTrueCount);
+ }
+ cond.end(*this);
+
+ cond.begin(*this);
+ EmitBlock(RHSBlock);
+ EmitBranchOnBoolExpr(CondOp->getRHS(), TrueBlock, FalseBlock,
+ TrueCount - LHSScaledTrueCount);
+ cond.end(*this);
+
+ return;
+ }
+
+ if (const CXXThrowExpr *Throw = dyn_cast<CXXThrowExpr>(Cond)) {
+ // Conditional operator handling can give us a throw expression as a
+ // condition for a case like:
+ // br(c ? throw x : y, t, f) -> br(c, br(throw x, t, f), br(y, t, f)
+ // Fold this to:
+ // br(c, throw x, br(y, t, f))
+ EmitCXXThrowExpr(Throw, /*KeepInsertionPoint*/false);
+ return;
+ }
+
+ // If the branch has a condition wrapped by __builtin_unpredictable,
+ // create metadata that specifies that the branch is unpredictable.
+ // Don't bother if not optimizing because that metadata would not be used.
+ llvm::MDNode *Unpredictable = nullptr;
+ auto *Call = dyn_cast<CallExpr>(Cond->IgnoreImpCasts());
+ if (Call && CGM.getCodeGenOpts().OptimizationLevel != 0) {
+ auto *FD = dyn_cast_or_null<FunctionDecl>(Call->getCalleeDecl());
+ if (FD && FD->getBuiltinID() == Builtin::BI__builtin_unpredictable) {
+ llvm::MDBuilder MDHelper(getLLVMContext());
+ Unpredictable = MDHelper.createUnpredictable();
+ }
+ }
+
+ // Create branch weights based on the number of times we get here and the
+ // number of times the condition should be true.
+ uint64_t CurrentCount = std::max(getCurrentProfileCount(), TrueCount);
+ llvm::MDNode *Weights =
+ createProfileWeights(TrueCount, CurrentCount - TrueCount);
+
+ // Emit the code with the fully general case.
+ llvm::Value *CondV;
+ {
+ ApplyDebugLocation DL(*this, Cond);
+ CondV = EvaluateExprAsBool(Cond);
+ }
+ Builder.CreateCondBr(CondV, TrueBlock, FalseBlock, Weights, Unpredictable);
+}
+
+/// ErrorUnsupported - Print out an error that codegen doesn't support the
+/// specified stmt yet.
+void CodeGenFunction::ErrorUnsupported(const Stmt *S, const char *Type) {
+ CGM.ErrorUnsupported(S, Type);
+}
+
+/// emitNonZeroVLAInit - Emit the "zero" initialization of a
+/// variable-length array whose elements have a non-zero bit-pattern.
+///
+/// \param baseType the inner-most element type of the array
+/// \param src - a char* pointing to the bit-pattern for a single
+/// base element of the array
+/// \param sizeInChars - the total size of the VLA, in chars
+static void emitNonZeroVLAInit(CodeGenFunction &CGF, QualType baseType,
+ Address dest, Address src,
+ llvm::Value *sizeInChars) {
+ CGBuilderTy &Builder = CGF.Builder;
+
+ CharUnits baseSize = CGF.getContext().getTypeSizeInChars(baseType);
+ llvm::Value *baseSizeInChars
+ = llvm::ConstantInt::get(CGF.IntPtrTy, baseSize.getQuantity());
+
+ Address begin =
+ Builder.CreateElementBitCast(dest, CGF.Int8Ty, "vla.begin");
+ llvm::Value *end =
+ Builder.CreateInBoundsGEP(begin.getPointer(), sizeInChars, "vla.end");
+
+ llvm::BasicBlock *originBB = CGF.Builder.GetInsertBlock();
+ llvm::BasicBlock *loopBB = CGF.createBasicBlock("vla-init.loop");
+ llvm::BasicBlock *contBB = CGF.createBasicBlock("vla-init.cont");
+
+ // Make a loop over the VLA. C99 guarantees that the VLA element
+ // count must be nonzero.
+ CGF.EmitBlock(loopBB);
+
+ llvm::PHINode *cur = Builder.CreatePHI(begin.getType(), 2, "vla.cur");
+ cur->addIncoming(begin.getPointer(), originBB);
+
+ CharUnits curAlign =
+ dest.getAlignment().alignmentOfArrayElement(baseSize);
+
+ // memcpy the individual element bit-pattern.
+ Builder.CreateMemCpy(Address(cur, curAlign), src, baseSizeInChars,
+ /*volatile*/ false);
+
+ // Go to the next element.
+ llvm::Value *next =
+ Builder.CreateInBoundsGEP(CGF.Int8Ty, cur, baseSizeInChars, "vla.next");
+
+ // Leave if that's the end of the VLA.
+ llvm::Value *done = Builder.CreateICmpEQ(next, end, "vla-init.isdone");
+ Builder.CreateCondBr(done, contBB, loopBB);
+ cur->addIncoming(next, loopBB);
+
+ CGF.EmitBlock(contBB);
+}
+
+void
+CodeGenFunction::EmitNullInitialization(Address DestPtr, QualType Ty) {
+ // Ignore empty classes in C++.
+ if (getLangOpts().CPlusPlus) {
+ if (const RecordType *RT = Ty->getAs<RecordType>()) {
+ if (cast<CXXRecordDecl>(RT->getDecl())->isEmpty())
+ return;
+ }
+ }
+
+ // Cast the dest ptr to the appropriate i8 pointer type.
+ if (DestPtr.getElementType() != Int8Ty)
+ DestPtr = Builder.CreateElementBitCast(DestPtr, Int8Ty);
+
+ // Get size and alignment info for this aggregate.
+ CharUnits size = getContext().getTypeSizeInChars(Ty);
+
+ llvm::Value *SizeVal;
+ const VariableArrayType *vla;
+
+ // Don't bother emitting a zero-byte memset.
+ if (size.isZero()) {
+ // But note that getTypeInfo returns 0 for a VLA.
+ if (const VariableArrayType *vlaType =
+ dyn_cast_or_null<VariableArrayType>(
+ getContext().getAsArrayType(Ty))) {
+ auto VlaSize = getVLASize(vlaType);
+ SizeVal = VlaSize.NumElts;
+ CharUnits eltSize = getContext().getTypeSizeInChars(VlaSize.Type);
+ if (!eltSize.isOne())
+ SizeVal = Builder.CreateNUWMul(SizeVal, CGM.getSize(eltSize));
+ vla = vlaType;
+ } else {
+ return;
+ }
+ } else {
+ SizeVal = CGM.getSize(size);
+ vla = nullptr;
+ }
+
+ // If the type contains a pointer to data member we can't memset it to zero.
+ // Instead, create a null constant and copy it to the destination.
+ // TODO: there are other patterns besides zero that we can usefully memset,
+ // like -1, which happens to be the pattern used by member-pointers.
+ if (!CGM.getTypes().isZeroInitializable(Ty)) {
+ // For a VLA, emit a single element, then splat that over the VLA.
+ if (vla) Ty = getContext().getBaseElementType(vla);
+
+ llvm::Constant *NullConstant = CGM.EmitNullConstant(Ty);
+
+ llvm::GlobalVariable *NullVariable =
+ new llvm::GlobalVariable(CGM.getModule(), NullConstant->getType(),
+ /*isConstant=*/true,
+ llvm::GlobalVariable::PrivateLinkage,
+ NullConstant, Twine());
+ CharUnits NullAlign = DestPtr.getAlignment();
+ NullVariable->setAlignment(NullAlign.getAsAlign());
+ Address SrcPtr(Builder.CreateBitCast(NullVariable, Builder.getInt8PtrTy()),
+ NullAlign);
+
+ if (vla) return emitNonZeroVLAInit(*this, Ty, DestPtr, SrcPtr, SizeVal);
+
+ // Get and call the appropriate llvm.memcpy overload.
+ Builder.CreateMemCpy(DestPtr, SrcPtr, SizeVal, false);
+ return;
+ }
+
+ // Otherwise, just memset the whole thing to zero. This is legal
+ // because in LLVM, all default initializers (other than the ones we just
+ // handled above) are guaranteed to have a bit pattern of all zeros.
+ Builder.CreateMemSet(DestPtr, Builder.getInt8(0), SizeVal, false);
+}
+
+llvm::BlockAddress *CodeGenFunction::GetAddrOfLabel(const LabelDecl *L) {
+ // Make sure that there is a block for the indirect goto.
+ if (!IndirectBranch)
+ GetIndirectGotoBlock();
+
+ llvm::BasicBlock *BB = getJumpDestForLabel(L).getBlock();
+
+ // Make sure the indirect branch includes all of the address-taken blocks.
+ IndirectBranch->addDestination(BB);
+ return llvm::BlockAddress::get(CurFn, BB);
+}
+
+llvm::BasicBlock *CodeGenFunction::GetIndirectGotoBlock() {
+ // If we already made the indirect branch for indirect goto, return its block.
+ if (IndirectBranch) return IndirectBranch->getParent();
+
+ CGBuilderTy TmpBuilder(*this, createBasicBlock("indirectgoto"));
+
+ // Create the PHI node that indirect gotos will add entries to.
+ llvm::Value *DestVal = TmpBuilder.CreatePHI(Int8PtrTy, 0,
+ "indirect.goto.dest");
+
+ // Create the indirect branch instruction.
+ IndirectBranch = TmpBuilder.CreateIndirectBr(DestVal);
+ return IndirectBranch->getParent();
+}
+
+/// Computes the length of an array in elements, as well as the base
+/// element type and a properly-typed first element pointer.
+llvm::Value *CodeGenFunction::emitArrayLength(const ArrayType *origArrayType,
+ QualType &baseType,
+ Address &addr) {
+ const ArrayType *arrayType = origArrayType;
+
+ // If it's a VLA, we have to load the stored size. Note that
+ // this is the size of the VLA in bytes, not its size in elements.
+ llvm::Value *numVLAElements = nullptr;
+ if (isa<VariableArrayType>(arrayType)) {
+ numVLAElements = getVLASize(cast<VariableArrayType>(arrayType)).NumElts;
+
+ // Walk into all VLAs. This doesn't require changes to addr,
+ // which has type T* where T is the first non-VLA element type.
+ do {
+ QualType elementType = arrayType->getElementType();
+ arrayType = getContext().getAsArrayType(elementType);
+
+ // If we only have VLA components, 'addr' requires no adjustment.
+ if (!arrayType) {
+ baseType = elementType;
+ return numVLAElements;
+ }
+ } while (isa<VariableArrayType>(arrayType));
+
+ // We get out here only if we find a constant array type
+ // inside the VLA.
+ }
+
+ // We have some number of constant-length arrays, so addr should
+ // have LLVM type [M x [N x [...]]]*. Build a GEP that walks
+ // down to the first element of addr.
+ SmallVector<llvm::Value*, 8> gepIndices;
+
+ // GEP down to the array type.
+ llvm::ConstantInt *zero = Builder.getInt32(0);
+ gepIndices.push_back(zero);
+
+ uint64_t countFromCLAs = 1;
+ QualType eltType;
+
+ llvm::ArrayType *llvmArrayType =
+ dyn_cast<llvm::ArrayType>(addr.getElementType());
+ while (llvmArrayType) {
+ assert(isa<ConstantArrayType>(arrayType));
+ assert(cast<ConstantArrayType>(arrayType)->getSize().getZExtValue()
+ == llvmArrayType->getNumElements());
+
+ gepIndices.push_back(zero);
+ countFromCLAs *= llvmArrayType->getNumElements();
+ eltType = arrayType->getElementType();
+
+ llvmArrayType =
+ dyn_cast<llvm::ArrayType>(llvmArrayType->getElementType());
+ arrayType = getContext().getAsArrayType(arrayType->getElementType());
+ assert((!llvmArrayType || arrayType) &&
+ "LLVM and Clang types are out-of-synch");
+ }
+
+ if (arrayType) {
+ // From this point onwards, the Clang array type has been emitted
+ // as some other type (probably a packed struct). Compute the array
+ // size, and just emit the 'begin' expression as a bitcast.
+ while (arrayType) {
+ countFromCLAs *=
+ cast<ConstantArrayType>(arrayType)->getSize().getZExtValue();
+ eltType = arrayType->getElementType();
+ arrayType = getContext().getAsArrayType(eltType);
+ }
+
+ llvm::Type *baseType = ConvertType(eltType);
+ addr = Builder.CreateElementBitCast(addr, baseType, "array.begin");
+ } else {
+ // Create the actual GEP.
+ addr = Address(Builder.CreateInBoundsGEP(addr.getPointer(),
+ gepIndices, "array.begin"),
+ addr.getAlignment());
+ }
+
+ baseType = eltType;
+
+ llvm::Value *numElements
+ = llvm::ConstantInt::get(SizeTy, countFromCLAs);
+
+ // If we had any VLA dimensions, factor them in.
+ if (numVLAElements)
+ numElements = Builder.CreateNUWMul(numVLAElements, numElements);
+
+ return numElements;
+}
+
+CodeGenFunction::VlaSizePair CodeGenFunction::getVLASize(QualType type) {
+ const VariableArrayType *vla = getContext().getAsVariableArrayType(type);
+ assert(vla && "type was not a variable array type!");
+ return getVLASize(vla);
+}
+
+CodeGenFunction::VlaSizePair
+CodeGenFunction::getVLASize(const VariableArrayType *type) {
+ // The number of elements so far; always size_t.
+ llvm::Value *numElements = nullptr;
+
+ QualType elementType;
+ do {
+ elementType = type->getElementType();
+ llvm::Value *vlaSize = VLASizeMap[type->getSizeExpr()];
+ assert(vlaSize && "no size for VLA!");
+ assert(vlaSize->getType() == SizeTy);
+
+ if (!numElements) {
+ numElements = vlaSize;
+ } else {
+ // It's undefined behavior if this wraps around, so mark it that way.
+ // FIXME: Teach -fsanitize=undefined to trap this.
+ numElements = Builder.CreateNUWMul(numElements, vlaSize);
+ }
+ } while ((type = getContext().getAsVariableArrayType(elementType)));
+
+ return { numElements, elementType };
+}
+
+CodeGenFunction::VlaSizePair
+CodeGenFunction::getVLAElements1D(QualType type) {
+ const VariableArrayType *vla = getContext().getAsVariableArrayType(type);
+ assert(vla && "type was not a variable array type!");
+ return getVLAElements1D(vla);
+}
+
+CodeGenFunction::VlaSizePair
+CodeGenFunction::getVLAElements1D(const VariableArrayType *Vla) {
+ llvm::Value *VlaSize = VLASizeMap[Vla->getSizeExpr()];
+ assert(VlaSize && "no size for VLA!");
+ assert(VlaSize->getType() == SizeTy);
+ return { VlaSize, Vla->getElementType() };
+}
+
+void CodeGenFunction::EmitVariablyModifiedType(QualType type) {
+ assert(type->isVariablyModifiedType() &&
+ "Must pass variably modified type to EmitVLASizes!");
+
+ EnsureInsertPoint();
+
+ // We're going to walk down into the type and look for VLA
+ // expressions.
+ do {
+ assert(type->isVariablyModifiedType());
+
+ const Type *ty = type.getTypePtr();
+ switch (ty->getTypeClass()) {
+
+#define TYPE(Class, Base)
+#define ABSTRACT_TYPE(Class, Base)
+#define NON_CANONICAL_TYPE(Class, Base)
+#define DEPENDENT_TYPE(Class, Base) case Type::Class:
+#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base)
+#include "clang/AST/TypeNodes.inc"
+ llvm_unreachable("unexpected dependent type!");
+
+ // These types are never variably-modified.
+ case Type::Builtin:
+ case Type::Complex:
+ case Type::Vector:
+ case Type::ExtVector:
+ case Type::Record:
+ case Type::Enum:
+ case Type::Elaborated:
+ case Type::TemplateSpecialization:
+ case Type::ObjCTypeParam:
+ case Type::ObjCObject:
+ case Type::ObjCInterface:
+ case Type::ObjCObjectPointer:
+ llvm_unreachable("type class is never variably-modified!");
+
+ case Type::Adjusted:
+ type = cast<AdjustedType>(ty)->getAdjustedType();
+ break;
+
+ case Type::Decayed:
+ type = cast<DecayedType>(ty)->getPointeeType();
+ break;
+
+ case Type::Pointer:
+ type = cast<PointerType>(ty)->getPointeeType();
+ break;
+
+ case Type::BlockPointer:
+ type = cast<BlockPointerType>(ty)->getPointeeType();
+ break;
+
+ case Type::LValueReference:
+ case Type::RValueReference:
+ type = cast<ReferenceType>(ty)->getPointeeType();
+ break;
+
+ case Type::MemberPointer:
+ type = cast<MemberPointerType>(ty)->getPointeeType();
+ break;
+
+ case Type::ConstantArray:
+ case Type::IncompleteArray:
+ // Losing element qualification here is fine.
+ type = cast<ArrayType>(ty)->getElementType();
+ break;
+
+ case Type::VariableArray: {
+ // Losing element qualification here is fine.
+ const VariableArrayType *vat = cast<VariableArrayType>(ty);
+
+ // Unknown size indication requires no size computation.
+ // Otherwise, evaluate and record it.
+ if (const Expr *size = vat->getSizeExpr()) {
+ // It's possible that we might have emitted this already,
+ // e.g. with a typedef and a pointer to it.
+ llvm::Value *&entry = VLASizeMap[size];
+ if (!entry) {
+ llvm::Value *Size = EmitScalarExpr(size);
+
+ // C11 6.7.6.2p5:
+ // If the size is an expression that is not an integer constant
+ // expression [...] each time it is evaluated it shall have a value
+ // greater than zero.
+ if (SanOpts.has(SanitizerKind::VLABound) &&
+ size->getType()->isSignedIntegerType()) {
+ SanitizerScope SanScope(this);
+ llvm::Value *Zero = llvm::Constant::getNullValue(Size->getType());
+ llvm::Constant *StaticArgs[] = {
+ EmitCheckSourceLocation(size->getBeginLoc()),
+ EmitCheckTypeDescriptor(size->getType())};
+ EmitCheck(std::make_pair(Builder.CreateICmpSGT(Size, Zero),
+ SanitizerKind::VLABound),
+ SanitizerHandler::VLABoundNotPositive, StaticArgs, Size);
+ }
+
+ // Always zexting here would be wrong if it weren't
+ // undefined behavior to have a negative bound.
+ entry = Builder.CreateIntCast(Size, SizeTy, /*signed*/ false);
+ }
+ }
+ type = vat->getElementType();
+ break;
+ }
+
+ case Type::FunctionProto:
+ case Type::FunctionNoProto:
+ type = cast<FunctionType>(ty)->getReturnType();
+ break;
+
+ case Type::Paren:
+ case Type::TypeOf:
+ case Type::UnaryTransform:
+ case Type::Attributed:
+ case Type::SubstTemplateTypeParm:
+ case Type::PackExpansion:
+ case Type::MacroQualified:
+ // Keep walking after single level desugaring.
+ type = type.getSingleStepDesugaredType(getContext());
+ break;
+
+ case Type::Typedef:
+ case Type::Decltype:
+ case Type::Auto:
+ case Type::DeducedTemplateSpecialization:
+ // Stop walking: nothing to do.
+ return;
+
+ case Type::TypeOfExpr:
+ // Stop walking: emit typeof expression.
+ EmitIgnoredExpr(cast<TypeOfExprType>(ty)->getUnderlyingExpr());
+ return;
+
+ case Type::Atomic:
+ type = cast<AtomicType>(ty)->getValueType();
+ break;
+
+ case Type::Pipe:
+ type = cast<PipeType>(ty)->getElementType();
+ break;
+ }
+ } while (type->isVariablyModifiedType());
+}
+
+Address CodeGenFunction::EmitVAListRef(const Expr* E) {
+ if (getContext().getBuiltinVaListType()->isArrayType())
+ return EmitPointerWithAlignment(E);
+ return EmitLValue(E).getAddress(*this);
+}
+
+Address CodeGenFunction::EmitMSVAListRef(const Expr *E) {
+ return EmitLValue(E).getAddress(*this);
+}
+
+void CodeGenFunction::EmitDeclRefExprDbgValue(const DeclRefExpr *E,
+ const APValue &Init) {
+ assert(Init.hasValue() && "Invalid DeclRefExpr initializer!");
+ if (CGDebugInfo *Dbg = getDebugInfo())
+ if (CGM.getCodeGenOpts().hasReducedDebugInfo())
+ Dbg->EmitGlobalVariable(E->getDecl(), Init);
+}
+
+CodeGenFunction::PeepholeProtection
+CodeGenFunction::protectFromPeepholes(RValue rvalue) {
+ // At the moment, the only aggressive peephole we do in IR gen
+ // is trunc(zext) folding, but if we add more, we can easily
+ // extend this protection.
+
+ if (!rvalue.isScalar()) return PeepholeProtection();
+ llvm::Value *value = rvalue.getScalarVal();
+ if (!isa<llvm::ZExtInst>(value)) return PeepholeProtection();
+
+ // Just make an extra bitcast.
+ assert(HaveInsertPoint());
+ llvm::Instruction *inst = new llvm::BitCastInst(value, value->getType(), "",
+ Builder.GetInsertBlock());
+
+ PeepholeProtection protection;
+ protection.Inst = inst;
+ return protection;
+}
+
+void CodeGenFunction::unprotectFromPeepholes(PeepholeProtection protection) {
+ if (!protection.Inst) return;
+
+ // In theory, we could try to duplicate the peepholes now, but whatever.
+ protection.Inst->eraseFromParent();
+}
+
+void CodeGenFunction::EmitAlignmentAssumption(llvm::Value *PtrValue,
+ QualType Ty, SourceLocation Loc,
+ SourceLocation AssumptionLoc,
+ llvm::Value *Alignment,
+ llvm::Value *OffsetValue) {
+ llvm::Value *TheCheck;
+ llvm::Instruction *Assumption = Builder.CreateAlignmentAssumption(
+ CGM.getDataLayout(), PtrValue, Alignment, OffsetValue, &TheCheck);
+ if (SanOpts.has(SanitizerKind::Alignment)) {
+ EmitAlignmentAssumptionCheck(PtrValue, Ty, Loc, AssumptionLoc, Alignment,
+ OffsetValue, TheCheck, Assumption);
+ }
+}
+
+void CodeGenFunction::EmitAlignmentAssumption(llvm::Value *PtrValue,
+ const Expr *E,
+ SourceLocation AssumptionLoc,
+ llvm::Value *Alignment,
+ llvm::Value *OffsetValue) {
+ if (auto *CE = dyn_cast<CastExpr>(E))
+ E = CE->getSubExprAsWritten();
+ QualType Ty = E->getType();
+ SourceLocation Loc = E->getExprLoc();
+
+ EmitAlignmentAssumption(PtrValue, Ty, Loc, AssumptionLoc, Alignment,
+ OffsetValue);
+}
+
+llvm::Value *CodeGenFunction::EmitAnnotationCall(llvm::Function *AnnotationFn,
+ llvm::Value *AnnotatedVal,
+ StringRef AnnotationStr,
+ SourceLocation Location) {
+ llvm::Value *Args[4] = {
+ AnnotatedVal,
+ Builder.CreateBitCast(CGM.EmitAnnotationString(AnnotationStr), Int8PtrTy),
+ Builder.CreateBitCast(CGM.EmitAnnotationUnit(Location), Int8PtrTy),
+ CGM.EmitAnnotationLineNo(Location)
+ };
+ return Builder.CreateCall(AnnotationFn, Args);
+}
+
+void CodeGenFunction::EmitVarAnnotations(const VarDecl *D, llvm::Value *V) {
+ assert(D->hasAttr<AnnotateAttr>() && "no annotate attribute");
+ // FIXME We create a new bitcast for every annotation because that's what
+ // llvm-gcc was doing.
+ for (const auto *I : D->specific_attrs<AnnotateAttr>())
+ EmitAnnotationCall(CGM.getIntrinsic(llvm::Intrinsic::var_annotation),
+ Builder.CreateBitCast(V, CGM.Int8PtrTy, V->getName()),
+ I->getAnnotation(), D->getLocation());
+}
+
+Address CodeGenFunction::EmitFieldAnnotations(const FieldDecl *D,
+ Address Addr) {
+ assert(D->hasAttr<AnnotateAttr>() && "no annotate attribute");
+ llvm::Value *V = Addr.getPointer();
+ llvm::Type *VTy = V->getType();
+ llvm::Function *F = CGM.getIntrinsic(llvm::Intrinsic::ptr_annotation,
+ CGM.Int8PtrTy);
+
+ for (const auto *I : D->specific_attrs<AnnotateAttr>()) {
+ // FIXME Always emit the cast inst so we can differentiate between
+ // annotation on the first field of a struct and annotation on the struct
+ // itself.
+ if (VTy != CGM.Int8PtrTy)
+ V = Builder.CreateBitCast(V, CGM.Int8PtrTy);
+ V = EmitAnnotationCall(F, V, I->getAnnotation(), D->getLocation());
+ V = Builder.CreateBitCast(V, VTy);
+ }
+
+ return Address(V, Addr.getAlignment());
+}
+
+CodeGenFunction::CGCapturedStmtInfo::~CGCapturedStmtInfo() { }
+
+CodeGenFunction::SanitizerScope::SanitizerScope(CodeGenFunction *CGF)
+ : CGF(CGF) {
+ assert(!CGF->IsSanitizerScope);
+ CGF->IsSanitizerScope = true;
+}
+
+CodeGenFunction::SanitizerScope::~SanitizerScope() {
+ CGF->IsSanitizerScope = false;
+}
+
+void CodeGenFunction::InsertHelper(llvm::Instruction *I,
+ const llvm::Twine &Name,
+ llvm::BasicBlock *BB,
+ llvm::BasicBlock::iterator InsertPt) const {
+ LoopStack.InsertHelper(I);
+ if (IsSanitizerScope)
+ CGM.getSanitizerMetadata()->disableSanitizerForInstruction(I);
+}
+
+void CGBuilderInserter::InsertHelper(
+ llvm::Instruction *I, const llvm::Twine &Name, llvm::BasicBlock *BB,
+ llvm::BasicBlock::iterator InsertPt) const {
+ llvm::IRBuilderDefaultInserter::InsertHelper(I, Name, BB, InsertPt);
+ if (CGF)
+ CGF->InsertHelper(I, Name, BB, InsertPt);
+}
+
+static bool hasRequiredFeatures(const SmallVectorImpl<StringRef> &ReqFeatures,
+ CodeGenModule &CGM, const FunctionDecl *FD,
+ std::string &FirstMissing) {
+ // If there aren't any required features listed then go ahead and return.
+ if (ReqFeatures.empty())
+ return false;
+
+ // Now build up the set of caller features and verify that all the required
+ // features are there.
+ llvm::StringMap<bool> CallerFeatureMap;
+ CGM.getContext().getFunctionFeatureMap(CallerFeatureMap, FD);
+
+ // If we have at least one of the features in the feature list return
+ // true, otherwise return false.
+ return std::all_of(
+ ReqFeatures.begin(), ReqFeatures.end(), [&](StringRef Feature) {
+ SmallVector<StringRef, 1> OrFeatures;
+ Feature.split(OrFeatures, '|');
+ return llvm::any_of(OrFeatures, [&](StringRef Feature) {
+ if (!CallerFeatureMap.lookup(Feature)) {
+ FirstMissing = Feature.str();
+ return false;
+ }
+ return true;
+ });
+ });
+}
+
+// Emits an error if we don't have a valid set of target features for the
+// called function.
+void CodeGenFunction::checkTargetFeatures(const CallExpr *E,
+ const FunctionDecl *TargetDecl) {
+ return checkTargetFeatures(E->getBeginLoc(), TargetDecl);
+}
+
+// Emits an error if we don't have a valid set of target features for the
+// called function.
+void CodeGenFunction::checkTargetFeatures(SourceLocation Loc,
+ const FunctionDecl *TargetDecl) {
+ // Early exit if this is an indirect call.
+ if (!TargetDecl)
+ return;
+
+ // Get the current enclosing function if it exists. If it doesn't
+ // we can't check the target features anyhow.
+ const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(CurCodeDecl);
+ if (!FD)
+ return;
+
+ // Grab the required features for the call. For a builtin this is listed in
+ // the td file with the default cpu, for an always_inline function this is any
+ // listed cpu and any listed features.
+ unsigned BuiltinID = TargetDecl->getBuiltinID();
+ std::string MissingFeature;
+ if (BuiltinID) {
+ SmallVector<StringRef, 1> ReqFeatures;
+ const char *FeatureList =
+ CGM.getContext().BuiltinInfo.getRequiredFeatures(BuiltinID);
+ // Return if the builtin doesn't have any required features.
+ if (!FeatureList || StringRef(FeatureList) == "")
+ return;
+ StringRef(FeatureList).split(ReqFeatures, ',');
+ if (!hasRequiredFeatures(ReqFeatures, CGM, FD, MissingFeature))
+ CGM.getDiags().Report(Loc, diag::err_builtin_needs_feature)
+ << TargetDecl->getDeclName()
+ << CGM.getContext().BuiltinInfo.getRequiredFeatures(BuiltinID);
+
+ } else if (!TargetDecl->isMultiVersion() &&
+ TargetDecl->hasAttr<TargetAttr>()) {
+ // Get the required features for the callee.
+
+ const TargetAttr *TD = TargetDecl->getAttr<TargetAttr>();
+ ParsedTargetAttr ParsedAttr =
+ CGM.getContext().filterFunctionTargetAttrs(TD);
+
+ SmallVector<StringRef, 1> ReqFeatures;
+ llvm::StringMap<bool> CalleeFeatureMap;
+ CGM.getContext().getFunctionFeatureMap(CalleeFeatureMap,
+ GlobalDecl(TargetDecl));
+
+ for (const auto &F : ParsedAttr.Features) {
+ if (F[0] == '+' && CalleeFeatureMap.lookup(F.substr(1)))
+ ReqFeatures.push_back(StringRef(F).substr(1));
+ }
+
+ for (const auto &F : CalleeFeatureMap) {
+ // Only positive features are "required".
+ if (F.getValue())
+ ReqFeatures.push_back(F.getKey());
+ }
+ if (!hasRequiredFeatures(ReqFeatures, CGM, FD, MissingFeature))
+ CGM.getDiags().Report(Loc, diag::err_function_needs_feature)
+ << FD->getDeclName() << TargetDecl->getDeclName() << MissingFeature;
+ }
+}
+
+void CodeGenFunction::EmitSanitizerStatReport(llvm::SanitizerStatKind SSK) {
+ if (!CGM.getCodeGenOpts().SanitizeStats)
+ return;
+
+ llvm::IRBuilder<> IRB(Builder.GetInsertBlock(), Builder.GetInsertPoint());
+ IRB.SetCurrentDebugLocation(Builder.getCurrentDebugLocation());
+ CGM.getSanStats().create(IRB, SSK);
+}
+
+llvm::Value *
+CodeGenFunction::FormResolverCondition(const MultiVersionResolverOption &RO) {
+ llvm::Value *Condition = nullptr;
+
+ if (!RO.Conditions.Architecture.empty())
+ Condition = EmitX86CpuIs(RO.Conditions.Architecture);
+
+ if (!RO.Conditions.Features.empty()) {
+ llvm::Value *FeatureCond = EmitX86CpuSupports(RO.Conditions.Features);
+ Condition =
+ Condition ? Builder.CreateAnd(Condition, FeatureCond) : FeatureCond;
+ }
+ return Condition;
+}
+
+static void CreateMultiVersionResolverReturn(CodeGenModule &CGM,
+ llvm::Function *Resolver,
+ CGBuilderTy &Builder,
+ llvm::Function *FuncToReturn,
+ bool SupportsIFunc) {
+ if (SupportsIFunc) {
+ Builder.CreateRet(FuncToReturn);
+ return;
+ }
+
+ llvm::SmallVector<llvm::Value *, 10> Args;
+ llvm::for_each(Resolver->args(),
+ [&](llvm::Argument &Arg) { Args.push_back(&Arg); });
+
+ llvm::CallInst *Result = Builder.CreateCall(FuncToReturn, Args);
+ Result->setTailCallKind(llvm::CallInst::TCK_MustTail);
+
+ if (Resolver->getReturnType()->isVoidTy())
+ Builder.CreateRetVoid();
+ else
+ Builder.CreateRet(Result);
+}
+
+void CodeGenFunction::EmitMultiVersionResolver(
+ llvm::Function *Resolver, ArrayRef<MultiVersionResolverOption> Options) {
+ assert(getContext().getTargetInfo().getTriple().isX86() &&
+ "Only implemented for x86 targets");
+
+ bool SupportsIFunc = getContext().getTargetInfo().supportsIFunc();
+
+ // Main function's basic block.
+ llvm::BasicBlock *CurBlock = createBasicBlock("resolver_entry", Resolver);
+ Builder.SetInsertPoint(CurBlock);
+ EmitX86CpuInit();
+
+ for (const MultiVersionResolverOption &RO : Options) {
+ Builder.SetInsertPoint(CurBlock);
+ llvm::Value *Condition = FormResolverCondition(RO);
+
+ // The 'default' or 'generic' case.
+ if (!Condition) {
+ assert(&RO == Options.end() - 1 &&
+ "Default or Generic case must be last");
+ CreateMultiVersionResolverReturn(CGM, Resolver, Builder, RO.Function,
+ SupportsIFunc);
+ return;
+ }
+
+ llvm::BasicBlock *RetBlock = createBasicBlock("resolver_return", Resolver);
+ CGBuilderTy RetBuilder(*this, RetBlock);
+ CreateMultiVersionResolverReturn(CGM, Resolver, RetBuilder, RO.Function,
+ SupportsIFunc);
+ CurBlock = createBasicBlock("resolver_else", Resolver);
+ Builder.CreateCondBr(Condition, RetBlock, CurBlock);
+ }
+
+ // If no generic/default, emit an unreachable.
+ Builder.SetInsertPoint(CurBlock);
+ llvm::CallInst *TrapCall = EmitTrapCall(llvm::Intrinsic::trap);
+ TrapCall->setDoesNotReturn();
+ TrapCall->setDoesNotThrow();
+ Builder.CreateUnreachable();
+ Builder.ClearInsertionPoint();
+}
+
+// Loc - where the diagnostic will point, where in the source code this
+// alignment has failed.
+// SecondaryLoc - if present (will be present if sufficiently different from
+// Loc), the diagnostic will additionally point a "Note:" to this location.
+// It should be the location where the __attribute__((assume_aligned))
+// was written e.g.
+void CodeGenFunction::EmitAlignmentAssumptionCheck(
+ llvm::Value *Ptr, QualType Ty, SourceLocation Loc,
+ SourceLocation SecondaryLoc, llvm::Value *Alignment,
+ llvm::Value *OffsetValue, llvm::Value *TheCheck,
+ llvm::Instruction *Assumption) {
+ assert(Assumption && isa<llvm::CallInst>(Assumption) &&
+ cast<llvm::CallInst>(Assumption)->getCalledValue() ==
+ llvm::Intrinsic::getDeclaration(
+ Builder.GetInsertBlock()->getParent()->getParent(),
+ llvm::Intrinsic::assume) &&
+ "Assumption should be a call to llvm.assume().");
+ assert(&(Builder.GetInsertBlock()->back()) == Assumption &&
+ "Assumption should be the last instruction of the basic block, "
+ "since the basic block is still being generated.");
+
+ if (!SanOpts.has(SanitizerKind::Alignment))
+ return;
+
+ // Don't check pointers to volatile data. The behavior here is implementation-
+ // defined.
+ if (Ty->getPointeeType().isVolatileQualified())
+ return;
+
+ // We need to temorairly remove the assumption so we can insert the
+ // sanitizer check before it, else the check will be dropped by optimizations.
+ Assumption->removeFromParent();
+
+ {
+ SanitizerScope SanScope(this);
+
+ if (!OffsetValue)
+ OffsetValue = Builder.getInt1(0); // no offset.
+
+ llvm::Constant *StaticData[] = {EmitCheckSourceLocation(Loc),
+ EmitCheckSourceLocation(SecondaryLoc),
+ EmitCheckTypeDescriptor(Ty)};
+ llvm::Value *DynamicData[] = {EmitCheckValue(Ptr),
+ EmitCheckValue(Alignment),
+ EmitCheckValue(OffsetValue)};
+ EmitCheck({std::make_pair(TheCheck, SanitizerKind::Alignment)},
+ SanitizerHandler::AlignmentAssumption, StaticData, DynamicData);
+ }
+
+ // We are now in the (new, empty) "cont" basic block.
+ // Reintroduce the assumption.
+ Builder.Insert(Assumption);
+ // FIXME: Assumption still has it's original basic block as it's Parent.
+}
+
+llvm::DebugLoc CodeGenFunction::SourceLocToDebugLoc(SourceLocation Location) {
+ if (CGDebugInfo *DI = getDebugInfo())
+ return DI->SourceLocToDebugLoc(Location);
+
+ return llvm::DebugLoc();
+}