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//===-- CodeGenFunction.h - Per-Function state for LLVM CodeGen -*- C++ -*-===//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
// This is the internal per-function state used for llvm translation.
#include "CGBuilder.h"
#include "CGDebugInfo.h"
#include "CGLoopInfo.h"
#include "CGValue.h"
#include "CodeGenModule.h"
#include "CodeGenPGO.h"
#include "EHScopeStack.h"
#include "VarBypassDetector.h"
#include "clang/AST/CharUnits.h"
#include "clang/AST/CurrentSourceLocExprScope.h"
#include "clang/AST/ExprCXX.h"
#include "clang/AST/ExprObjC.h"
#include "clang/AST/ExprOpenMP.h"
#include "clang/AST/Type.h"
#include "clang/Basic/ABI.h"
#include "clang/Basic/CapturedStmt.h"
#include "clang/Basic/CodeGenOptions.h"
#include "clang/Basic/OpenMPKinds.h"
#include "clang/Basic/TargetInfo.h"
#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/MapVector.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/IR/ValueHandle.h"
#include "llvm/Support/Debug.h"
#include "llvm/Transforms/Utils/SanitizerStats.h"
namespace llvm {
class BasicBlock;
class LLVMContext;
class MDNode;
class Module;
class SwitchInst;
class Twine;
class Value;
namespace clang {
class ASTContext;
class BlockDecl;
class CXXDestructorDecl;
class CXXForRangeStmt;
class CXXTryStmt;
class Decl;
class LabelDecl;
class EnumConstantDecl;
class FunctionDecl;
class FunctionProtoType;
class LabelStmt;
class ObjCContainerDecl;
class ObjCInterfaceDecl;
class ObjCIvarDecl;
class ObjCMethodDecl;
class ObjCImplementationDecl;
class ObjCPropertyImplDecl;
class TargetInfo;
class VarDecl;
class ObjCForCollectionStmt;
class ObjCAtTryStmt;
class ObjCAtThrowStmt;
class ObjCAtSynchronizedStmt;
class ObjCAutoreleasePoolStmt;
namespace analyze_os_log {
class OSLogBufferLayout;
namespace CodeGen {
class CodeGenTypes;
class CGCallee;
class CGFunctionInfo;
class CGRecordLayout;
class CGBlockInfo;
class BlockByrefHelpers;
class BlockByrefInfo;
class BlockFlags;
class BlockFieldFlags;
class RegionCodeGenTy;
class TargetCodeGenInfo;
struct OMPTaskDataTy;
struct CGCoroData;
/// The kind of evaluation to perform on values of a particular
/// type. Basically, is the code in CGExprScalar, CGExprComplex, or
/// CGExprAgg?
/// TODO: should vectors maybe be split out into their own thing?
enum TypeEvaluationKind {
SANITIZER_CHECK(AddOverflow, add_overflow, 0) \
SANITIZER_CHECK(BuiltinUnreachable, builtin_unreachable, 0) \
SANITIZER_CHECK(CFICheckFail, cfi_check_fail, 0) \
SANITIZER_CHECK(DivremOverflow, divrem_overflow, 0) \
SANITIZER_CHECK(DynamicTypeCacheMiss, dynamic_type_cache_miss, 0) \
SANITIZER_CHECK(FloatCastOverflow, float_cast_overflow, 0) \
SANITIZER_CHECK(FunctionTypeMismatch, function_type_mismatch, 1) \
SANITIZER_CHECK(ImplicitConversion, implicit_conversion, 0) \
SANITIZER_CHECK(InvalidBuiltin, invalid_builtin, 0) \
SANITIZER_CHECK(LoadInvalidValue, load_invalid_value, 0) \
SANITIZER_CHECK(MissingReturn, missing_return, 0) \
SANITIZER_CHECK(MulOverflow, mul_overflow, 0) \
SANITIZER_CHECK(NegateOverflow, negate_overflow, 0) \
SANITIZER_CHECK(NullabilityArg, nullability_arg, 0) \
SANITIZER_CHECK(NullabilityReturn, nullability_return, 1) \
SANITIZER_CHECK(NonnullArg, nonnull_arg, 0) \
SANITIZER_CHECK(NonnullReturn, nonnull_return, 1) \
SANITIZER_CHECK(OutOfBounds, out_of_bounds, 0) \
SANITIZER_CHECK(PointerOverflow, pointer_overflow, 0) \
SANITIZER_CHECK(ShiftOutOfBounds, shift_out_of_bounds, 0) \
SANITIZER_CHECK(SubOverflow, sub_overflow, 0) \
SANITIZER_CHECK(TypeMismatch, type_mismatch, 1) \
SANITIZER_CHECK(AlignmentAssumption, alignment_assumption, 0) \
SANITIZER_CHECK(VLABoundNotPositive, vla_bound_not_positive, 0)
enum SanitizerHandler {
#define SANITIZER_CHECK(Enum, Name, Version) Enum,
/// Helper class with most of the code for saving a value for a
/// conditional expression cleanup.
struct DominatingLLVMValue {
typedef llvm::PointerIntPair<llvm::Value*, 1, bool> saved_type;
/// Answer whether the given value needs extra work to be saved.
static bool needsSaving(llvm::Value *value) {
// If it's not an instruction, we don't need to save.
if (!isa<llvm::Instruction>(value)) return false;
// If it's an instruction in the entry block, we don't need to save.
llvm::BasicBlock *block = cast<llvm::Instruction>(value)->getParent();
return (block != &block->getParent()->getEntryBlock());
static saved_type save(CodeGenFunction &CGF, llvm::Value *value);
static llvm::Value *restore(CodeGenFunction &CGF, saved_type value);
/// A partial specialization of DominatingValue for llvm::Values that
/// might be llvm::Instructions.
template <class T> struct DominatingPointer<T,true> : DominatingLLVMValue {
typedef T *type;
static type restore(CodeGenFunction &CGF, saved_type value) {
return static_cast<T*>(DominatingLLVMValue::restore(CGF, value));
/// A specialization of DominatingValue for Address.
template <> struct DominatingValue<Address> {
typedef Address type;
struct saved_type {
DominatingLLVMValue::saved_type SavedValue;
CharUnits Alignment;
static bool needsSaving(type value) {
return DominatingLLVMValue::needsSaving(value.getPointer());
static saved_type save(CodeGenFunction &CGF, type value) {
return { DominatingLLVMValue::save(CGF, value.getPointer()),
value.getAlignment() };
static type restore(CodeGenFunction &CGF, saved_type value) {
return Address(DominatingLLVMValue::restore(CGF, value.SavedValue),
/// A specialization of DominatingValue for RValue.
template <> struct DominatingValue<RValue> {
typedef RValue type;
class saved_type {
enum Kind { ScalarLiteral, ScalarAddress, AggregateLiteral,
AggregateAddress, ComplexAddress };
llvm::Value *Value;
unsigned K : 3;
unsigned Align : 29;
saved_type(llvm::Value *v, Kind k, unsigned a = 0)
: Value(v), K(k), Align(a) {}
static bool needsSaving(RValue value);
static saved_type save(CodeGenFunction &CGF, RValue value);
RValue restore(CodeGenFunction &CGF);
// implementations in CGCleanup.cpp
static bool needsSaving(type value) {
return saved_type::needsSaving(value);
static saved_type save(CodeGenFunction &CGF, type value) {
return saved_type::save(CGF, value);
static type restore(CodeGenFunction &CGF, saved_type value) {
return value.restore(CGF);
/// CodeGenFunction - This class organizes the per-function state that is used
/// while generating LLVM code.
class CodeGenFunction : public CodeGenTypeCache {
CodeGenFunction(const CodeGenFunction &) = delete;
void operator=(const CodeGenFunction &) = delete;
friend class CGCXXABI;
/// A jump destination is an abstract label, branching to which may
/// require a jump out through normal cleanups.
struct JumpDest {
JumpDest() : Block(nullptr), ScopeDepth(), Index(0) {}
JumpDest(llvm::BasicBlock *Block,
EHScopeStack::stable_iterator Depth,
unsigned Index)
: Block(Block), ScopeDepth(Depth), Index(Index) {}
bool isValid() const { return Block != nullptr; }
llvm::BasicBlock *getBlock() const { return Block; }
EHScopeStack::stable_iterator getScopeDepth() const { return ScopeDepth; }
unsigned getDestIndex() const { return Index; }
// This should be used cautiously.
void setScopeDepth(EHScopeStack::stable_iterator depth) {
ScopeDepth = depth;
llvm::BasicBlock *Block;
EHScopeStack::stable_iterator ScopeDepth;
unsigned Index;
CodeGenModule &CGM; // Per-module state.
const TargetInfo &Target;
typedef std::pair<llvm::Value *, llvm::Value *> ComplexPairTy;
LoopInfoStack LoopStack;
CGBuilderTy Builder;
// Stores variables for which we can't generate correct lifetime markers
// because of jumps.
VarBypassDetector Bypasses;
// CodeGen lambda for loops and support for ordered clause
typedef llvm::function_ref<void(CodeGenFunction &, const OMPLoopDirective &,
typedef llvm::function_ref<void(CodeGenFunction &, SourceLocation,
const unsigned, const bool)>
// Codegen lambda for loop bounds in worksharing loop constructs
typedef llvm::function_ref<std::pair<LValue, LValue>(
CodeGenFunction &, const OMPExecutableDirective &S)>
// Codegen lambda for loop bounds in dispatch-based loop implementation
typedef llvm::function_ref<std::pair<llvm::Value *, llvm::Value *>(
CodeGenFunction &, const OMPExecutableDirective &S, Address LB,
Address UB)>
/// CGBuilder insert helper. This function is called after an
/// instruction is created using Builder.
void InsertHelper(llvm::Instruction *I, const llvm::Twine &Name,
llvm::BasicBlock *BB,
llvm::BasicBlock::iterator InsertPt) const;
/// CurFuncDecl - Holds the Decl for the current outermost
/// non-closure context.
const Decl *CurFuncDecl;
/// CurCodeDecl - This is the inner-most code context, which includes blocks.
const Decl *CurCodeDecl;
const CGFunctionInfo *CurFnInfo;
QualType FnRetTy;
llvm::Function *CurFn = nullptr;
// Holds coroutine data if the current function is a coroutine. We use a
// wrapper to manage its lifetime, so that we don't have to define CGCoroData
// in this header.
struct CGCoroInfo {
std::unique_ptr<CGCoroData> Data;
CGCoroInfo CurCoro;
bool isCoroutine() const {
return CurCoro.Data != nullptr;
/// CurGD - The GlobalDecl for the current function being compiled.
GlobalDecl CurGD;
/// PrologueCleanupDepth - The cleanup depth enclosing all the
/// cleanups associated with the parameters.
EHScopeStack::stable_iterator PrologueCleanupDepth;
/// ReturnBlock - Unified return block.
JumpDest ReturnBlock;
/// ReturnValue - The temporary alloca to hold the return
/// value. This is invalid iff the function has no return value.
Address ReturnValue = Address::invalid();
/// ReturnValuePointer - The temporary alloca to hold a pointer to sret.
/// This is invalid if sret is not in use.
Address ReturnValuePointer = Address::invalid();
/// Return true if a label was seen in the current scope.
bool hasLabelBeenSeenInCurrentScope() const {
if (CurLexicalScope)
return CurLexicalScope->hasLabels();
return !LabelMap.empty();
/// AllocaInsertPoint - This is an instruction in the entry block before which
/// we prefer to insert allocas.
llvm::AssertingVH<llvm::Instruction> AllocaInsertPt;
/// API for captured statement code generation.
class CGCapturedStmtInfo {
explicit CGCapturedStmtInfo(CapturedRegionKind K = CR_Default)
: Kind(K), ThisValue(nullptr), CXXThisFieldDecl(nullptr) {}
explicit CGCapturedStmtInfo(const CapturedStmt &S,
CapturedRegionKind K = CR_Default)
: Kind(K), ThisValue(nullptr), CXXThisFieldDecl(nullptr) {
RecordDecl::field_iterator Field =
for (CapturedStmt::const_capture_iterator I = S.capture_begin(),
E = S.capture_end();
I != E; ++I, ++Field) {
if (I->capturesThis())
CXXThisFieldDecl = *Field;
else if (I->capturesVariable())
CaptureFields[I->getCapturedVar()->getCanonicalDecl()] = *Field;
else if (I->capturesVariableByCopy())
CaptureFields[I->getCapturedVar()->getCanonicalDecl()] = *Field;
virtual ~CGCapturedStmtInfo();
CapturedRegionKind getKind() const { return Kind; }
virtual void setContextValue(llvm::Value *V) { ThisValue = V; }
// Retrieve the value of the context parameter.
virtual llvm::Value *getContextValue() const { return ThisValue; }
/// Lookup the captured field decl for a variable.
virtual const FieldDecl *lookup(const VarDecl *VD) const {
return CaptureFields.lookup(VD->getCanonicalDecl());
bool isCXXThisExprCaptured() const { return getThisFieldDecl() != nullptr; }
virtual FieldDecl *getThisFieldDecl() const { return CXXThisFieldDecl; }
static bool classof(const CGCapturedStmtInfo *) {
return true;
/// Emit the captured statement body.
virtual void EmitBody(CodeGenFunction &CGF, const Stmt *S) {
/// Get the name of the capture helper.
virtual StringRef getHelperName() const { return "__captured_stmt"; }
/// The kind of captured statement being generated.
CapturedRegionKind Kind;
/// Keep the map between VarDecl and FieldDecl.
llvm::SmallDenseMap<const VarDecl *, FieldDecl *> CaptureFields;
/// The base address of the captured record, passed in as the first
/// argument of the parallel region function.
llvm::Value *ThisValue;
/// Captured 'this' type.
FieldDecl *CXXThisFieldDecl;
CGCapturedStmtInfo *CapturedStmtInfo = nullptr;
/// RAII for correct setting/restoring of CapturedStmtInfo.
class CGCapturedStmtRAII {
CodeGenFunction &CGF;
CGCapturedStmtInfo *PrevCapturedStmtInfo;
CGCapturedStmtRAII(CodeGenFunction &CGF,
CGCapturedStmtInfo *NewCapturedStmtInfo)
: CGF(CGF), PrevCapturedStmtInfo(CGF.CapturedStmtInfo) {
CGF.CapturedStmtInfo = NewCapturedStmtInfo;
~CGCapturedStmtRAII() { CGF.CapturedStmtInfo = PrevCapturedStmtInfo; }
/// An abstract representation of regular/ObjC call/message targets.
class AbstractCallee {
/// The function declaration of the callee.
const Decl *CalleeDecl;
AbstractCallee() : CalleeDecl(nullptr) {}
AbstractCallee(const FunctionDecl *FD) : CalleeDecl(FD) {}
AbstractCallee(const ObjCMethodDecl *OMD) : CalleeDecl(OMD) {}
bool hasFunctionDecl() const {
return dyn_cast_or_null<FunctionDecl>(CalleeDecl);
const Decl *getDecl() const { return CalleeDecl; }
unsigned getNumParams() const {
if (const auto *FD = dyn_cast<FunctionDecl>(CalleeDecl))
return FD->getNumParams();
return cast<ObjCMethodDecl>(CalleeDecl)->param_size();
const ParmVarDecl *getParamDecl(unsigned I) const {
if (const auto *FD = dyn_cast<FunctionDecl>(CalleeDecl))
return FD->getParamDecl(I);
return *(cast<ObjCMethodDecl>(CalleeDecl)->param_begin() + I);
/// Sanitizers enabled for this function.
SanitizerSet SanOpts;
/// True if CodeGen currently emits code implementing sanitizer checks.
bool IsSanitizerScope = false;
/// RAII object to set/unset CodeGenFunction::IsSanitizerScope.
class SanitizerScope {
CodeGenFunction *CGF;
SanitizerScope(CodeGenFunction *CGF);
/// In C++, whether we are code generating a thunk. This controls whether we
/// should emit cleanups.
bool CurFuncIsThunk = false;
/// In ARC, whether we should autorelease the return value.
bool AutoreleaseResult = false;
/// Whether we processed a Microsoft-style asm block during CodeGen. These can
/// potentially set the return value.
bool SawAsmBlock = false;
const NamedDecl *CurSEHParent = nullptr;
/// True if the current function is an outlined SEH helper. This can be a
/// finally block or filter expression.
bool IsOutlinedSEHHelper = false;
/// True if CodeGen currently emits code inside presereved access index
/// region.
bool IsInPreservedAIRegion = false;
const CodeGen::CGBlockInfo *BlockInfo = nullptr;
llvm::Value *BlockPointer = nullptr;
llvm::DenseMap<const VarDecl *, FieldDecl *> LambdaCaptureFields;
FieldDecl *LambdaThisCaptureField = nullptr;
/// A mapping from NRVO variables to the flags used to indicate
/// when the NRVO has been applied to this variable.
llvm::DenseMap<const VarDecl *, llvm::Value *> NRVOFlags;
EHScopeStack EHStack;
llvm::SmallVector<char, 256> LifetimeExtendedCleanupStack;
llvm::SmallVector<const JumpDest *, 2> SEHTryEpilogueStack;
llvm::Instruction *CurrentFuncletPad = nullptr;
class CallLifetimeEnd final : public EHScopeStack::Cleanup {
llvm::Value *Addr;
llvm::Value *Size;
CallLifetimeEnd(Address addr, llvm::Value *size)
: Addr(addr.getPointer()), Size(size) {}
void Emit(CodeGenFunction &CGF, Flags flags) override {
CGF.EmitLifetimeEnd(Size, Addr);
/// Header for data within LifetimeExtendedCleanupStack.
struct LifetimeExtendedCleanupHeader {
/// The size of the following cleanup object.
unsigned Size;
/// The kind of cleanup to push: a value from the CleanupKind enumeration.
unsigned Kind : 31;
/// Whether this is a conditional cleanup.
unsigned IsConditional : 1;
size_t getSize() const { return Size; }
CleanupKind getKind() const { return (CleanupKind)Kind; }
bool isConditional() const { return IsConditional; }
/// i32s containing the indexes of the cleanup destinations.
Address NormalCleanupDest = Address::invalid();
unsigned NextCleanupDestIndex = 1;
/// FirstBlockInfo - The head of a singly-linked-list of block layouts.
CGBlockInfo *FirstBlockInfo = nullptr;
/// EHResumeBlock - Unified block containing a call to
llvm::BasicBlock *EHResumeBlock = nullptr;
/// The exception slot. All landing pads write the current exception pointer
/// into this alloca.
llvm::Value *ExceptionSlot = nullptr;
/// The selector slot. Under the MandatoryCleanup model, all landing pads
/// write the current selector value into this alloca.
llvm::AllocaInst *EHSelectorSlot = nullptr;
/// A stack of exception code slots. Entering an __except block pushes a slot
/// on the stack and leaving pops one. The __exception_code() intrinsic loads
/// a value from the top of the stack.
SmallVector<Address, 1> SEHCodeSlotStack;
/// Value returned by __exception_info intrinsic.
llvm::Value *SEHInfo = nullptr;
/// Emits a landing pad for the current EH stack.
llvm::BasicBlock *EmitLandingPad();
llvm::BasicBlock *getInvokeDestImpl();
template <class T>
typename DominatingValue<T>::saved_type saveValueInCond(T value) {
return DominatingValue<T>::save(*this, value);
/// ObjCEHValueStack - Stack of Objective-C exception values, used for
/// rethrows.
SmallVector<llvm::Value*, 8> ObjCEHValueStack;
/// A class controlling the emission of a finally block.
class FinallyInfo {
/// Where the catchall's edge through the cleanup should go.
JumpDest RethrowDest;
/// A function to call to enter the catch.
llvm::FunctionCallee BeginCatchFn;
/// An i1 variable indicating whether or not the @finally is
/// running for an exception.
llvm::AllocaInst *ForEHVar;
/// An i8* variable into which the exception pointer to rethrow
/// has been saved.
llvm::AllocaInst *SavedExnVar;
void enter(CodeGenFunction &CGF, const Stmt *Finally,
llvm::FunctionCallee beginCatchFn,
llvm::FunctionCallee endCatchFn, llvm::FunctionCallee rethrowFn);
void exit(CodeGenFunction &CGF);
/// Returns true inside SEH __try blocks.
bool isSEHTryScope() const { return !SEHTryEpilogueStack.empty(); }
/// Returns true while emitting a cleanuppad.
bool isCleanupPadScope() const {
return CurrentFuncletPad && isa<llvm::CleanupPadInst>(CurrentFuncletPad);
/// pushFullExprCleanup - Push a cleanup to be run at the end of the
/// current full-expression. Safe against the possibility that
/// we're currently inside a conditionally-evaluated expression.
template <class T, class... As>
void pushFullExprCleanup(CleanupKind kind, As... A) {
// If we're not in a conditional branch, or if none of the
// arguments requires saving, then use the unconditional cleanup.
if (!isInConditionalBranch())
return EHStack.pushCleanup<T>(kind, A...);
// Stash values in a tuple so we can guarantee the order of saves.
typedef std::tuple<typename DominatingValue<As>::saved_type...> SavedTuple;
SavedTuple Saved{saveValueInCond(A)...};
typedef EHScopeStack::ConditionalCleanup<T, As...> CleanupType;
EHStack.pushCleanupTuple<CleanupType>(kind, Saved);
/// Queue a cleanup to be pushed after finishing the current
/// full-expression.
template <class T, class... As>
void pushCleanupAfterFullExpr(CleanupKind Kind, As... A) {
if (!isInConditionalBranch())
return pushCleanupAfterFullExprImpl<T>(Kind, Address::invalid(), A...);
Address ActiveFlag = createCleanupActiveFlag();
assert(!DominatingValue<Address>::needsSaving(ActiveFlag) &&
"cleanup active flag should never need saving");
typedef std::tuple<typename DominatingValue<As>::saved_type...> SavedTuple;
SavedTuple Saved{saveValueInCond(A)...};
typedef EHScopeStack::ConditionalCleanup<T, As...> CleanupType;
pushCleanupAfterFullExprImpl<CleanupType>(Kind, ActiveFlag, Saved);
template <class T, class... As>
void pushCleanupAfterFullExprImpl(CleanupKind Kind, Address ActiveFlag,
As... A) {
LifetimeExtendedCleanupHeader Header = {sizeof(T), Kind,
size_t OldSize = LifetimeExtendedCleanupStack.size();
LifetimeExtendedCleanupStack.size() + sizeof(Header) + Header.Size +
(Header.IsConditional ? sizeof(ActiveFlag) : 0));
static_assert(sizeof(Header) % alignof(T) == 0,
"Cleanup will be allocated on misaligned address");
char *Buffer = &LifetimeExtendedCleanupStack[OldSize];
new (Buffer) LifetimeExtendedCleanupHeader(Header);
new (Buffer + sizeof(Header)) T(A...);
if (Header.IsConditional)
new (Buffer + sizeof(Header) + sizeof(T)) Address(ActiveFlag);
/// Set up the last cleanup that was pushed as a conditional
/// full-expression cleanup.
void initFullExprCleanup() {
void initFullExprCleanupWithFlag(Address ActiveFlag);
Address createCleanupActiveFlag();
/// PushDestructorCleanup - Push a cleanup to call the
/// complete-object destructor of an object of the given type at the
/// given address. Does nothing if T is not a C++ class type with a
/// non-trivial destructor.
void PushDestructorCleanup(QualType T, Address Addr);
/// PushDestructorCleanup - Push a cleanup to call the
/// complete-object variant of the given destructor on the object at
/// the given address.
void PushDestructorCleanup(const CXXDestructorDecl *Dtor, QualType T,
Address Addr);
/// PopCleanupBlock - Will pop the cleanup entry on the stack and
/// process all branch fixups.
void PopCleanupBlock(bool FallThroughIsBranchThrough = false);
/// DeactivateCleanupBlock - Deactivates the given cleanup block.
/// The block cannot be reactivated. Pops it if it's the top of the
/// stack.
/// \param DominatingIP - An instruction which is known to
/// dominate the current IP (if set) and which lies along
/// all paths of execution between the current IP and the
/// the point at which the cleanup comes into scope.
void DeactivateCleanupBlock(EHScopeStack::stable_iterator Cleanup,
llvm::Instruction *DominatingIP);
/// ActivateCleanupBlock - Activates an initially-inactive cleanup.
/// Cannot be used to resurrect a deactivated cleanup.
/// \param DominatingIP - An instruction which is known to
/// dominate the current IP (if set) and which lies along
/// all paths of execution between the current IP and the
/// the point at which the cleanup comes into scope.
void ActivateCleanupBlock(EHScopeStack::stable_iterator Cleanup,
llvm::Instruction *DominatingIP);
/// Enters a new scope for capturing cleanups, all of which
/// will be executed once the scope is exited.
class RunCleanupsScope {
EHScopeStack::stable_iterator CleanupStackDepth, OldCleanupScopeDepth;
size_t LifetimeExtendedCleanupStackSize;
bool OldDidCallStackSave;
bool PerformCleanup;
RunCleanupsScope(const RunCleanupsScope &) = delete;
void operator=(const RunCleanupsScope &) = delete;
CodeGenFunction& CGF;
/// Enter a new cleanup scope.
explicit RunCleanupsScope(CodeGenFunction &CGF)
: PerformCleanup(true), CGF(CGF)
CleanupStackDepth = CGF.EHStack.stable_begin();
LifetimeExtendedCleanupStackSize =
OldDidCallStackSave = CGF.DidCallStackSave;
CGF.DidCallStackSave = false;
OldCleanupScopeDepth = CGF.CurrentCleanupScopeDepth;
CGF.CurrentCleanupScopeDepth = CleanupStackDepth;
/// Exit this cleanup scope, emitting any accumulated cleanups.
~RunCleanupsScope() {
if (PerformCleanup)
/// Determine whether this scope requires any cleanups.
bool requiresCleanups() const {
return CGF.EHStack.stable_begin() != CleanupStackDepth;
/// Force the emission of cleanups now, instead of waiting
/// until this object is destroyed.
/// \param ValuesToReload - A list of values that need to be available at
/// the insertion point after cleanup emission. If cleanup emission created
/// a shared cleanup block, these value pointers will be rewritten.
/// Otherwise, they not will be modified.
void ForceCleanup(std::initializer_list<llvm::Value**> ValuesToReload = {}) {
assert(PerformCleanup && "Already forced cleanup");
CGF.DidCallStackSave = OldDidCallStackSave;
CGF.PopCleanupBlocks(CleanupStackDepth, LifetimeExtendedCleanupStackSize,
PerformCleanup = false;
CGF.CurrentCleanupScopeDepth = OldCleanupScopeDepth;
// Cleanup stack depth of the RunCleanupsScope that was pushed most recently.
EHScopeStack::stable_iterator CurrentCleanupScopeDepth =
class LexicalScope : public RunCleanupsScope {
SourceRange Range;
SmallVector<const LabelDecl*, 4> Labels;
LexicalScope *ParentScope;
LexicalScope(const LexicalScope &) = delete;
void operator=(const LexicalScope &) = delete;
/// Enter a new cleanup scope.
explicit LexicalScope(CodeGenFunction &CGF, SourceRange Range)
: RunCleanupsScope(CGF), Range(Range), ParentScope(CGF.CurLexicalScope) {
CGF.CurLexicalScope = this;
if (CGDebugInfo *DI = CGF.getDebugInfo())
DI->EmitLexicalBlockStart(CGF.Builder, Range.getBegin());
void addLabel(const LabelDecl *label) {
assert(PerformCleanup && "adding label to dead scope?");
/// Exit this cleanup scope, emitting any accumulated
/// cleanups.
~LexicalScope() {
if (CGDebugInfo *DI = CGF.getDebugInfo())
DI->EmitLexicalBlockEnd(CGF.Builder, Range.getEnd());
// If we should perform a cleanup, force them now. Note that
// this ends the cleanup scope before rescoping any labels.
if (PerformCleanup) {
ApplyDebugLocation DL(CGF, Range.getEnd());
/// Force the emission of cleanups now, instead of waiting
/// until this object is destroyed.
void ForceCleanup() {
CGF.CurLexicalScope = ParentScope;
if (!Labels.empty())
bool hasLabels() const {
return !Labels.empty();
void rescopeLabels();
typedef llvm::DenseMap<const Decl *, Address> DeclMapTy;
/// The class used to assign some variables some temporarily addresses.
class OMPMapVars {
DeclMapTy SavedLocals;
DeclMapTy SavedTempAddresses;
OMPMapVars(const OMPMapVars &) = delete;
void operator=(const OMPMapVars &) = delete;
explicit OMPMapVars() = default;
~OMPMapVars() {
assert(SavedLocals.empty() && "Did not restored original addresses.");
/// Sets the address of the variable \p LocalVD to be \p TempAddr in
/// function \p CGF.
/// \return true if at least one variable was set already, false otherwise.
bool setVarAddr(CodeGenFunction &CGF, const VarDecl *LocalVD,
Address TempAddr) {
LocalVD = LocalVD->getCanonicalDecl();
// Only save it once.
if (SavedLocals.count(LocalVD)) return false;
// Copy the existing local entry to SavedLocals.
auto it = CGF.LocalDeclMap.find(LocalVD);
if (it != CGF.LocalDeclMap.end())
SavedLocals.try_emplace(LocalVD, it->second);
SavedLocals.try_emplace(LocalVD, Address::invalid());
// Generate the private entry.
QualType VarTy = LocalVD->getType();
if (VarTy->isReferenceType()) {
Address Temp = CGF.CreateMemTemp(VarTy);
CGF.Builder.CreateStore(TempAddr.getPointer(), Temp);
TempAddr = Temp;
SavedTempAddresses.try_emplace(LocalVD, TempAddr);
return true;
/// Applies new addresses to the list of the variables.
/// \return true if at least one variable is using new address, false
/// otherwise.
bool apply(CodeGenFunction &CGF) {
copyInto(SavedTempAddresses, CGF.LocalDeclMap);
return !SavedLocals.empty();
/// Restores original addresses of the variables.
void restore(CodeGenFunction &CGF) {
if (!SavedLocals.empty()) {
copyInto(SavedLocals, CGF.LocalDeclMap);
/// Copy all the entries in the source map over the corresponding
/// entries in the destination, which must exist.
static void copyInto(const DeclMapTy &Src, DeclMapTy &Dest) {
for (auto &Pair : Src) {
if (!Pair.second.isValid()) {
auto I = Dest.find(Pair.first);
if (I != Dest.end())
I->second = Pair.second;
/// The scope used to remap some variables as private in the OpenMP loop body
/// (or other captured region emitted without outlining), and to restore old
/// vars back on exit.
class OMPPrivateScope : public RunCleanupsScope {
OMPMapVars MappedVars;
OMPPrivateScope(const OMPPrivateScope &) = delete;
void operator=(const OMPPrivateScope &) = delete;
/// Enter a new OpenMP private scope.
explicit OMPPrivateScope(CodeGenFunction &CGF) : RunCleanupsScope(CGF) {}
/// Registers \p LocalVD variable as a private and apply \p PrivateGen
/// function for it to generate corresponding private variable. \p
/// PrivateGen returns an address of the generated private variable.
/// \return true if the variable is registered as private, false if it has
/// been privatized already.
bool addPrivate(const VarDecl *LocalVD,
const llvm::function_ref<Address()> PrivateGen) {
assert(PerformCleanup && "adding private to dead scope");
return MappedVars.setVarAddr(CGF, LocalVD, PrivateGen());
/// Privatizes local variables previously registered as private.
/// Registration is separate from the actual privatization to allow
/// initializers use values of the original variables, not the private one.
/// This is important, for example, if the private variable is a class
/// variable initialized by a constructor that references other private
/// variables. But at initialization original variables must be used, not
/// private copies.
/// \return true if at least one variable was privatized, false otherwise.
bool Privatize() { return MappedVars.apply(CGF); }
void ForceCleanup() {
/// Exit scope - all the mapped variables are restored.
~OMPPrivateScope() {
if (PerformCleanup)
/// Checks if the global variable is captured in current function.
bool isGlobalVarCaptured(const VarDecl *VD) const {
VD = VD->getCanonicalDecl();
return !VD->isLocalVarDeclOrParm() && CGF.LocalDeclMap.count(VD) > 0;
/// Takes the old cleanup stack size and emits the cleanup blocks
/// that have been added.
PopCleanupBlocks(EHScopeStack::stable_iterator OldCleanupStackSize,
std::initializer_list<llvm::Value **> ValuesToReload = {});
/// Takes the old cleanup stack size and emits the cleanup blocks
/// that have been added, then adds all lifetime-extended cleanups from
/// the given position to the stack.
PopCleanupBlocks(EHScopeStack::stable_iterator OldCleanupStackSize,
size_t OldLifetimeExtendedStackSize,
std::initializer_list<llvm::Value **> ValuesToReload = {});
void ResolveBranchFixups(llvm::BasicBlock *Target);
/// The given basic block lies in the current EH scope, but may be a
/// target of a potentially scope-crossing jump; get a stable handle
/// to which we can perform this jump later.
JumpDest getJumpDestInCurrentScope(llvm::BasicBlock *Target) {
return JumpDest(Target,
/// The given basic block lies in the current EH scope, but may be a
/// target of a potentially scope-crossing jump; get a stable handle
/// to which we can perform this jump later.
JumpDest getJumpDestInCurrentScope(StringRef Name = StringRef()) {
return getJumpDestInCurrentScope(createBasicBlock(Name));
/// EmitBranchThroughCleanup - Emit a branch from the current insert
/// block through the normal cleanup handling code (if any) and then
/// on to \arg Dest.
void EmitBranchThroughCleanup(JumpDest Dest);
/// isObviouslyBranchWithoutCleanups - Return true if a branch to the
/// specified destination obviously has no cleanups to run. 'false' is always
/// a conservatively correct answer for this method.
bool isObviouslyBranchWithoutCleanups(JumpDest Dest) const;
/// popCatchScope - Pops the catch scope at the top of the EHScope
/// stack, emitting any required code (other than the catch handlers
/// themselves).
void popCatchScope();
llvm::BasicBlock *getEHResumeBlock(bool isCleanup);
llvm::BasicBlock *getEHDispatchBlock(EHScopeStack::stable_iterator scope);
llvm::BasicBlock *
getFuncletEHDispatchBlock(EHScopeStack::stable_iterator scope);
/// An object to manage conditionally-evaluated expressions.
class ConditionalEvaluation {
llvm::BasicBlock *StartBB;
ConditionalEvaluation(CodeGenFunction &CGF)
: StartBB(CGF.Builder.GetInsertBlock()) {}
void begin(CodeGenFunction &CGF) {
assert(CGF.OutermostConditional != this);
if (!CGF.OutermostConditional)
CGF.OutermostConditional = this;
void end(CodeGenFunction &CGF) {
assert(CGF.OutermostConditional != nullptr);
if (CGF.OutermostConditional == this)
CGF.OutermostConditional = nullptr;
/// Returns a block which will be executed prior to each
/// evaluation of the conditional code.
llvm::BasicBlock *getStartingBlock() const {
return StartBB;
/// isInConditionalBranch - Return true if we're currently emitting
/// one branch or the other of a conditional expression.
bool isInConditionalBranch() const { return OutermostConditional != nullptr; }
void setBeforeOutermostConditional(llvm::Value *value, Address addr) {
llvm::BasicBlock *block = OutermostConditional->getStartingBlock();
auto store = new llvm::StoreInst(value, addr.getPointer(), &block->back());
/// An RAII object to record that we're evaluating a statement
/// expression.
class StmtExprEvaluation {
CodeGenFunction &CGF;
/// We have to save the outermost conditional: cleanups in a
/// statement expression aren't conditional just because the
/// StmtExpr is.
ConditionalEvaluation *SavedOutermostConditional;
StmtExprEvaluation(CodeGenFunction &CGF)
: CGF(CGF), SavedOutermostConditional(CGF.OutermostConditional) {
CGF.OutermostConditional = nullptr;
~StmtExprEvaluation() {
CGF.OutermostConditional = SavedOutermostConditional;
/// An object which temporarily prevents a value from being
/// destroyed by aggressive peephole optimizations that assume that
/// all uses of a value have been realized in the IR.
class PeepholeProtection {
llvm::Instruction *Inst;
friend class CodeGenFunction;
PeepholeProtection() : Inst(nullptr) {}
/// A non-RAII class containing all the information about a bound
/// opaque value. OpaqueValueMapping, below, is a RAII wrapper for
/// this which makes individual mappings very simple; using this
/// class directly is useful when you have a variable number of
/// opaque values or don't want the RAII functionality for some
/// reason.
class OpaqueValueMappingData {
const OpaqueValueExpr *OpaqueValue;
bool BoundLValue;
CodeGenFunction::PeepholeProtection Protection;
OpaqueValueMappingData(const OpaqueValueExpr *ov,
bool boundLValue)
: OpaqueValue(ov), BoundLValue(boundLValue) {}
OpaqueValueMappingData() : OpaqueValue(nullptr) {}
static bool shouldBindAsLValue(const Expr *expr) {
// gl-values should be bound as l-values for obvious reasons.
// Records should be bound as l-values because IR generation
// always keeps them in memory. Expressions of function type
// act exactly like l-values but are formally required to be
// r-values in C.
return expr->isGLValue() ||
expr->getType()->isFunctionType() ||
static OpaqueValueMappingData bind(CodeGenFunction &CGF,
const OpaqueValueExpr *ov,
const Expr *e) {
if (shouldBindAsLValue(ov))
return bind(CGF, ov, CGF.EmitLValue(e));
return bind(CGF, ov, CGF.EmitAnyExpr(e));
static OpaqueValueMappingData bind(CodeGenFunction &CGF,
const OpaqueValueExpr *ov,
const LValue &lv) {
CGF.OpaqueLValues.insert(std::make_pair(ov, lv));
return OpaqueValueMappingData(ov, true);
static OpaqueValueMappingData bind(CodeGenFunction &CGF,
const OpaqueValueExpr *ov,
const RValue &rv) {
CGF.OpaqueRValues.insert(std::make_pair(ov, rv));
OpaqueValueMappingData data(ov, false);
// Work around an extremely aggressive peephole optimization in
// EmitScalarConversion which assumes that all other uses of a
// value are extant.
data.Protection = CGF.protectFromPeepholes(rv);
return data;
bool isValid() const { return OpaqueValue != nullptr; }
void clear() { OpaqueValue = nullptr; }
void unbind(CodeGenFunction &CGF) {
assert(OpaqueValue && "no data to unbind!");
if (BoundLValue) {
} else {
/// An RAII object to set (and then clear) a mapping for an OpaqueValueExpr.
class OpaqueValueMapping {
CodeGenFunction &CGF;
OpaqueValueMappingData Data;
static bool shouldBindAsLValue(const Expr *expr) {
return OpaqueValueMappingData::shouldBindAsLValue(expr);
/// Build the opaque value mapping for the given conditional
/// operator if it's the GNU ?: extension. This is a common
/// enough pattern that the convenience operator is really
/// helpful.
OpaqueValueMapping(CodeGenFunction &CGF,
const AbstractConditionalOperator *op) : CGF(CGF) {
if (isa<ConditionalOperator>(op))
// Leave Data empty.
const BinaryConditionalOperator *e = cast<BinaryConditionalOperator>(op);
Data = OpaqueValueMappingData::bind(CGF, e->getOpaqueValue(),
/// Build the opaque value mapping for an OpaqueValueExpr whose source
/// expression is set to the expression the OVE represents.
OpaqueValueMapping(CodeGenFunction &CGF, const OpaqueValueExpr *OV)
: CGF(CGF) {
if (OV) {
assert(OV->getSourceExpr() && "wrong form of OpaqueValueMapping used "
"for OVE with no source expression");
Data = OpaqueValueMappingData::bind(CGF, OV, OV->getSourceExpr());
OpaqueValueMapping(CodeGenFunction &CGF,
const OpaqueValueExpr *opaqueValue,
LValue lvalue)
: CGF(CGF), Data(OpaqueValueMappingData::bind(CGF, opaqueValue, lvalue)) {
OpaqueValueMapping(CodeGenFunction &CGF,
const OpaqueValueExpr *opaqueValue,
RValue rvalue)
: CGF(CGF), Data(OpaqueValueMappingData::bind(CGF, opaqueValue, rvalue)) {
void pop() {
~OpaqueValueMapping() {
if (Data.isValid()) Data.unbind(CGF);
CGDebugInfo *DebugInfo;
/// Used to create unique names for artificial VLA size debug info variables.
unsigned VLAExprCounter = 0;
bool DisableDebugInfo = false;
/// DidCallStackSave - Whether llvm.stacksave has been called. Used to avoid
/// calling llvm.stacksave for multiple VLAs in the same scope.
bool DidCallStackSave = false;
/// IndirectBranch - The first time an indirect goto is seen we create a block
/// with an indirect branch. Every time we see the address of a label taken,
/// we add the label to the indirect goto. Every subsequent indirect goto is
/// codegen'd as a jump to the IndirectBranch's basic block.
llvm::IndirectBrInst *IndirectBranch = nullptr;
/// LocalDeclMap - This keeps track of the LLVM allocas or globals for local C
/// decls.
DeclMapTy LocalDeclMap;
// Keep track of the cleanups for callee-destructed parameters pushed to the
// cleanup stack so that they can be deactivated later.
llvm::DenseMap<const ParmVarDecl *, EHScopeStack::stable_iterator>
/// SizeArguments - If a ParmVarDecl had the pass_object_size attribute, this
/// will contain a mapping from said ParmVarDecl to its implicit "object_size"
/// parameter.
llvm::SmallDenseMap<const ParmVarDecl *, const ImplicitParamDecl *, 2>
/// Track escaped local variables with auto storage. Used during SEH
/// outlining to produce a call to llvm.localescape.
llvm::DenseMap<llvm::AllocaInst *, int> EscapedLocals;
/// LabelMap - This keeps track of the LLVM basic block for each C label.
llvm::DenseMap<const LabelDecl*, JumpDest> LabelMap;
// BreakContinueStack - This keeps track of where break and continue
// statements should jump to.
struct BreakContinue {
BreakContinue(JumpDest Break, JumpDest Continue)
: BreakBlock(Break), ContinueBlock(Continue) {}
JumpDest BreakBlock;
JumpDest ContinueBlock;
SmallVector<BreakContinue, 8> BreakContinueStack;
/// Handles cancellation exit points in OpenMP-related constructs.
class OpenMPCancelExitStack {
/// Tracks cancellation exit point and join point for cancel-related exit
/// and normal exit.
struct CancelExit {
CancelExit() = default;
CancelExit(OpenMPDirectiveKind Kind, JumpDest ExitBlock,
JumpDest ContBlock)
: Kind(Kind), ExitBlock(ExitBlock), ContBlock(ContBlock) {}
OpenMPDirectiveKind Kind = OMPD_unknown;
/// true if the exit block has been emitted already by the special
/// emitExit() call, false if the default codegen is used.
bool HasBeenEmitted = false;
JumpDest ExitBlock;
JumpDest ContBlock;
SmallVector<CancelExit, 8> Stack;
OpenMPCancelExitStack() : Stack(1) {}
~OpenMPCancelExitStack() = default;
/// Fetches the exit block for the current OpenMP construct.
JumpDest getExitBlock() const { return Stack.back().ExitBlock; }
/// Emits exit block with special codegen procedure specific for the related
/// OpenMP construct + emits code for normal construct cleanup.
void emitExit(CodeGenFunction &CGF, OpenMPDirectiveKind Kind,
const llvm::function_ref<void(CodeGenFunction &)> CodeGen) {
if (Stack.back().Kind == Kind && getExitBlock().isValid()) {
auto IP = CGF.Builder.saveAndClearIP();
Stack.back().HasBeenEmitted = true;
/// Enter the cancel supporting \a Kind construct.
/// \param Kind OpenMP directive that supports cancel constructs.
/// \param HasCancel true, if the construct has inner cancel directive,
/// false otherwise.
void enter(CodeGenFunction &CGF, OpenMPDirectiveKind Kind, bool HasCancel) {
HasCancel ? CGF.getJumpDestInCurrentScope("cancel.exit")
: JumpDest(),
HasCancel ? CGF.getJumpDestInCurrentScope("cancel.cont")
: JumpDest()});
/// Emits default exit point for the cancel construct (if the special one
/// has not be used) + join point for cancel/normal exits.
void exit(CodeGenFunction &CGF) {
if (getExitBlock().isValid()) {
bool HaveIP = CGF.HaveInsertPoint();
if (!Stack.back().HasBeenEmitted) {
if (HaveIP)
if (!HaveIP) {
OpenMPCancelExitStack OMPCancelStack;
/// Calculate branch weights appropriate for PGO data
llvm::MDNode *createProfileWeights(uint64_t TrueCount, uint64_t FalseCount);
llvm::MDNode *createProfileWeights(ArrayRef<uint64_t> Weights);
llvm::MDNode *createProfileWeightsForLoop(const Stmt *Cond,
uint64_t LoopCount);
/// Increment the profiler's counter for the given statement by \p StepV.
/// If \p StepV is null, the default increment is 1.
void incrementProfileCounter(const Stmt *S, llvm::Value *StepV = nullptr) {
if (CGM.getCodeGenOpts().hasProfileClangInstr())
PGO.emitCounterIncrement(Builder, S, StepV);
/// Get the profiler's count for the given statement.
uint64_t getProfileCount(const Stmt *S) {
Optional<uint64_t> Count = PGO.getStmtCount(S);
if (!Count.hasValue())
return 0;
return *Count;
/// Set the profiler's current count.
void setCurrentProfileCount(uint64_t Count) {
/// Get the profiler's current count. This is generally the count for the most
/// recently incremented counter.
uint64_t getCurrentProfileCount() {
return PGO.getCurrentRegionCount();
/// SwitchInsn - This is nearest current switch instruction. It is null if
/// current context is not in a switch.
llvm::SwitchInst *SwitchInsn = nullptr;
/// The branch weights of SwitchInsn when doing instrumentation based PGO.
SmallVector<uint64_t, 16> *SwitchWeights = nullptr;
/// CaseRangeBlock - This block holds if condition check for last case
/// statement range in current switch instruction.
llvm::BasicBlock *CaseRangeBlock = nullptr;
/// OpaqueLValues - Keeps track of the current set of opaque value
/// expressions.
llvm::DenseMap<const OpaqueValueExpr *, LValue> OpaqueLValues;
llvm::DenseMap<const OpaqueValueExpr *, RValue> OpaqueRValues;
// VLASizeMap - This keeps track of the associated size for each VLA type.
// We track this by the size expression rather than the type itself because
// in certain situations, like a const qualifier applied to an VLA typedef,
// multiple VLA types can share the same size expression.
// FIXME: Maybe this could be a stack of maps that is pushed/popped as we
// enter/leave scopes.
llvm::DenseMap<const Expr*, llvm::Value*> VLASizeMap;
/// A block containing a single 'unreachable' instruction. Created
/// lazily by getUnreachableBlock().
llvm::BasicBlock *UnreachableBlock = nullptr;
/// Counts of the number return expressions in the function.
unsigned NumReturnExprs = 0;
/// Count the number of simple (constant) return expressions in the function.
unsigned NumSimpleReturnExprs = 0;
/// The last regular (non-return) debug location (breakpoint) in the function.
SourceLocation LastStopPoint;
/// Source location information about the default argument or member
/// initializer expression we're evaluating, if any.
CurrentSourceLocExprScope CurSourceLocExprScope;
using SourceLocExprScopeGuard =
/// A scope within which we are constructing the fields of an object which
/// might use a CXXDefaultInitExpr. This stashes away a 'this' value to use
/// if we need to evaluate a CXXDefaultInitExpr within the evaluation.
class FieldConstructionScope {
FieldConstructionScope(CodeGenFunction &CGF, Address This)
: CGF(CGF), OldCXXDefaultInitExprThis(CGF.CXXDefaultInitExprThis) {
CGF.CXXDefaultInitExprThis = This;
~FieldConstructionScope() {
CGF.CXXDefaultInitExprThis = OldCXXDefaultInitExprThis;
CodeGenFunction &CGF;
Address OldCXXDefaultInitExprThis;
/// The scope of a CXXDefaultInitExpr. Within this scope, the value of 'this'
/// is overridden to be the object under construction.
class CXXDefaultInitExprScope {
CXXDefaultInitExprScope(CodeGenFunction &CGF, const CXXDefaultInitExpr *E)
: CGF(CGF), OldCXXThisValue(CGF.CXXThisValue),
SourceLocScope(E, CGF.CurSourceLocExprScope) {
CGF.CXXThisValue = CGF.CXXDefaultInitExprThis.getPointer();
CGF.CXXThisAlignment = CGF.CXXDefaultInitExprThis.getAlignment();
~CXXDefaultInitExprScope() {
CGF.CXXThisValue = OldCXXThisValue;
CGF.CXXThisAlignment = OldCXXThisAlignment;
CodeGenFunction &CGF;
llvm::Value *OldCXXThisValue;
CharUnits OldCXXThisAlignment;
SourceLocExprScopeGuard SourceLocScope;
struct CXXDefaultArgExprScope : SourceLocExprScopeGuard {
CXXDefaultArgExprScope(CodeGenFunction &CGF, const CXXDefaultArgExpr *E)
: SourceLocExprScopeGuard(E, CGF.CurSourceLocExprScope) {}
/// The scope of an ArrayInitLoopExpr. Within this scope, the value of the
/// current loop index is overridden.
class ArrayInitLoopExprScope {
ArrayInitLoopExprScope(CodeGenFunction &CGF, llvm::Value *Index)
: CGF(CGF), OldArrayInitIndex(CGF.ArrayInitIndex) {
CGF.ArrayInitIndex = Index;
~ArrayInitLoopExprScope() {
CGF.ArrayInitIndex = OldArrayInitIndex;
CodeGenFunction &CGF;
llvm::Value *OldArrayInitIndex;
class InlinedInheritingConstructorScope {
InlinedInheritingConstructorScope(CodeGenFunction &CGF, GlobalDecl GD)
: CGF(CGF), OldCurGD(CGF.CurGD), OldCurFuncDecl(CGF.CurFuncDecl),
OldReturnValue(CGF.ReturnValue), OldFnRetTy(CGF.FnRetTy),
std::move(CGF.CXXInheritedCtorInitExprArgs)) {
CGF.CurFuncDecl = CGF.CurCodeDecl =
CGF.CXXABIThisDecl = nullptr;
CGF.CXXABIThisValue = nullptr;
CGF.CXXThisValue = nullptr;
CGF.CXXABIThisAlignment = CharUnits();
CGF.CXXThisAlignment = CharUnits();
CGF.ReturnValue = Address::invalid();
CGF.FnRetTy = QualType();
~InlinedInheritingConstructorScope() {
CGF.CurGD = OldCurGD;
CGF.CurFuncDecl = OldCurFuncDecl;
CGF.CurCodeDecl = OldCurCodeDecl;
CGF.CXXABIThisValue = OldCXXABIThisValue;
CGF.CXXThisValue = OldCXXThisValue;
CGF.CXXABIThisAlignment = OldCXXABIThisAlignment;
CGF.CXXThisAlignment = OldCXXThisAlignment;
CGF.ReturnValue = OldReturnValue;
CGF.FnRetTy = OldFnRetTy;
CGF.CXXInheritedCtorInitExprArgs =
CodeGenFunction &CGF;
GlobalDecl OldCurGD;
const Decl *OldCurFuncDecl;
const Decl *OldCurCodeDecl;
ImplicitParamDecl *OldCXXABIThisDecl;
llvm::Value *OldCXXABIThisValue;
llvm::Value *OldCXXThisValue;
CharUnits OldCXXABIThisAlignment;
CharUnits OldCXXThisAlignment;
Address OldReturnValue;
QualType OldFnRetTy;
CallArgList OldCXXInheritedCtorInitExprArgs;
/// CXXThisDecl - When generating code for a C++ member function,
/// this will hold the implicit 'this' declaration.
ImplicitParamDecl *CXXABIThisDecl = nullptr;
llvm::Value *CXXABIThisValue = nullptr;
llvm::Value *CXXThisValue = nullptr;
CharUnits CXXABIThisAlignment;
CharUnits CXXThisAlignment;
/// The value of 'this' to use when evaluating CXXDefaultInitExprs within
/// this expression.
Address CXXDefaultInitExprThis = Address::invalid();
/// The current array initialization index when evaluating an
/// ArrayInitIndexExpr within an ArrayInitLoopExpr.
llvm::Value *ArrayInitIndex = nullptr;
/// The values of function arguments to use when evaluating
/// CXXInheritedCtorInitExprs within this context.
CallArgList CXXInheritedCtorInitExprArgs;
/// CXXStructorImplicitParamDecl - When generating code for a constructor or
/// destructor, this will hold the implicit argument (e.g. VTT).
ImplicitParamDecl *CXXStructorImplicitParamDecl = nullptr;
llvm::Value *CXXStructorImplicitParamValue = nullptr;
/// OutermostConditional - Points to the outermost active
/// conditional control. This is used so that we know if a
/// temporary should be destroyed conditionally.
ConditionalEvaluation *OutermostConditional = nullptr;
/// The current lexical scope.
LexicalScope *CurLexicalScope = nullptr;
/// The current source location that should be used for exception
/// handling code.
SourceLocation CurEHLocation;
/// BlockByrefInfos - For each __block variable, contains
/// information about the layout of the variable.
llvm::DenseMap<const ValueDecl *, BlockByrefInfo> BlockByrefInfos;
/// Used by -fsanitize=nullability-return to determine whether the return
/// value can be checked.
llvm::Value *RetValNullabilityPrecondition = nullptr;
/// Check if -fsanitize=nullability-return instrumentation is required for
/// this function.
bool requiresReturnValueNullabilityCheck() const {
return RetValNullabilityPrecondition;
/// Used to store precise source locations for return statements by the
/// runtime return value checks.
Address ReturnLocation = Address::invalid();
/// Check if the return value of this function requires sanitization.
bool requiresReturnValueCheck() const {
return requiresReturnValueNullabilityCheck() ||
(SanOpts.has(SanitizerKind::ReturnsNonnullAttribute) &&
CurCodeDecl && CurCodeDecl->getAttr<ReturnsNonNullAttr>());
llvm::BasicBlock *TerminateLandingPad = nullptr;
llvm::BasicBlock *TerminateHandler = nullptr;
llvm::BasicBlock *TrapBB = nullptr;
/// Terminate funclets keyed by parent funclet pad.
llvm::MapVector<llvm::Value *, llvm::BasicBlock *> TerminateFunclets;
/// Largest vector width used in ths function. Will be used to create a
/// function attribute.
unsigned LargestVectorWidth = 0;
/// True if we need emit the life-time markers.
const bool ShouldEmitLifetimeMarkers;
/// Add OpenCL kernel arg metadata and the kernel attribute metadata to
/// the function metadata.
void EmitOpenCLKernelMetadata(const FunctionDecl *FD,
llvm::Function *Fn);
CodeGenFunction(CodeGenModule &cgm, bool suppressNewContext=false);
CodeGenTypes &getTypes() const { return CGM.getTypes(); }
ASTContext &getContext() const { return CGM.getContext(); }
CGDebugInfo *getDebugInfo() {
if (DisableDebugInfo)
return nullptr;
return DebugInfo;
void disableDebugInfo() { DisableDebugInfo = true; }
void enableDebugInfo() { DisableDebugInfo = false; }
bool shouldUseFusedARCCalls() {
return CGM.getCodeGenOpts().OptimizationLevel == 0;
const LangOptions &getLangOpts() const { return CGM.getLangOpts(); }
/// Returns a pointer to the function's exception object and selector slot,
/// which is assigned in every landing pad.
Address getExceptionSlot();
Address getEHSelectorSlot();
/// Returns the contents of the function's exception object and selector
/// slots.
llvm::Value *getExceptionFromSlot();
llvm::Value *getSelectorFromSlot();
Address getNormalCleanupDestSlot();
llvm::BasicBlock *getUnreachableBlock() {
if (!UnreachableBlock) {
UnreachableBlock = createBasicBlock("unreachable");
new llvm::UnreachableInst(getLLVMContext(), UnreachableBlock);
return UnreachableBlock;
llvm::BasicBlock *getInvokeDest() {
if (!EHStack.requiresLandingPad()) return nullptr;
return getInvokeDestImpl();
bool currentFunctionUsesSEHTry() const { return CurSEHParent != nullptr; }
const TargetInfo &getTarget() const { return Target; }
llvm::LLVMContext &getLLVMContext() { return CGM.getLLVMContext(); }
const TargetCodeGenInfo &getTargetHooks() const {
return CGM.getTargetCodeGenInfo();
// Cleanups
typedef void Destroyer(CodeGenFunction &CGF, Address addr, QualType ty);
void pushIrregularPartialArrayCleanup(llvm::Value *arrayBegin,
Address arrayEndPointer,
QualType elementType,
CharUnits elementAlignment,
Destroyer *destroyer);
void pushRegularPartialArrayCleanup(llvm::Value *arrayBegin,
llvm::Value *arrayEnd,
QualType elementType,
CharUnits elementAlignment,
Destroyer *destroyer);
void pushDestroy(QualType::DestructionKind dtorKind,
Address addr, QualType type);
void pushEHDestroy(QualType::DestructionKind dtorKind,
Address addr, QualType type);
void pushDestroy(CleanupKind kind, Address addr, QualType type,
Destroyer *destroyer, bool useEHCleanupForArray);
void pushLifetimeExtendedDestroy(CleanupKind kind, Address addr,
QualType type, Destroyer *destroyer,
bool useEHCleanupForArray);
void pushCallObjectDeleteCleanup(const FunctionDecl *OperatorDelete,
llvm::Value *CompletePtr,
QualType ElementType);
void pushStackRestore(CleanupKind kind, Address SPMem);
void emitDestroy(Address addr, QualType type, Destroyer *destroyer,
bool useEHCleanupForArray);
llvm::Function *generateDestroyHelper(Address addr, QualType type,
Destroyer *destroyer,
bool useEHCleanupForArray,
const VarDecl *VD);
void emitArrayDestroy(llvm::Value *begin, llvm::Value *end,
QualType elementType, CharUnits elementAlign,
Destroyer *destroyer,
bool checkZeroLength, bool useEHCleanup);
Destroyer *getDestroyer(QualType::DestructionKind destructionKind);
/// Determines whether an EH cleanup is required to destroy a type
/// with the given destruction kind.
bool needsEHCleanup(QualType::DestructionKind kind) {
switch (kind) {
case QualType::DK_none:
return false;
case QualType::DK_cxx_destructor:
case QualType::DK_objc_weak_lifetime:
case QualType::DK_nontrivial_c_struct:
return getLangOpts().Exceptions;
case QualType::DK_objc_strong_lifetime:
return getLangOpts().Exceptions &&
llvm_unreachable("bad destruction kind");
CleanupKind getCleanupKind(QualType::DestructionKind kind) {
return (needsEHCleanup(kind) ? NormalAndEHCleanup : NormalCleanup);
// Objective-C
void GenerateObjCMethod(const ObjCMethodDecl *OMD);
void StartObjCMethod(const ObjCMethodDecl *MD, const ObjCContainerDecl *CD);
/// GenerateObjCGetter - Synthesize an Objective-C property getter function.
void GenerateObjCGetter(ObjCImplementationDecl *IMP,
const ObjCPropertyImplDecl *PID);
void generateObjCGetterBody(const ObjCImplementationDecl *classImpl,
const ObjCPropertyImplDecl *propImpl,
const ObjCMethodDecl *GetterMothodDecl,
llvm::Constant *AtomicHelperFn);
void GenerateObjCCtorDtorMethod(ObjCImplementationDecl *IMP,
ObjCMethodDecl *MD, bool ctor);
/// GenerateObjCSetter - Synthesize an Objective-C property setter function
/// for the given property.
void GenerateObjCSetter(ObjCImplementationDecl *IMP,
const ObjCPropertyImplDecl *PID);
void generateObjCSetterBody(const ObjCImplementationDecl *classImpl,
const ObjCPropertyImplDecl *propImpl,
llvm::Constant *AtomicHelperFn);
// Block Bits
/// Emit block literal.
/// \return an LLVM value which is a pointer to a struct which contains
/// information about the block, including the block invoke function, the
/// captured variables, etc.
llvm::Value *EmitBlockLiteral(const BlockExpr *);
static void destroyBlockInfos(CGBlockInfo *info);
llvm::Function *GenerateBlockFunction(GlobalDecl GD,
const CGBlockInfo &Info,
const DeclMapTy &ldm,
bool IsLambdaConversionToBlock,
bool BuildGlobalBlock);
/// Check if \p T is a C++ class that has a destructor that can throw.
static bool cxxDestructorCanThrow(QualType T);
llvm::Constant *GenerateCopyHelperFunction(const CGBlockInfo &blockInfo);
llvm::Constant *GenerateDestroyHelperFunction(const CGBlockInfo &blockInfo);
llvm::Constant *GenerateObjCAtomicSetterCopyHelperFunction(
const ObjCPropertyImplDecl *PID);
llvm::Constant *GenerateObjCAtomicGetterCopyHelperFunction(
const ObjCPropertyImplDecl *PID);
llvm::Value *EmitBlockCopyAndAutorelease(llvm::Value *Block, QualType Ty);
void BuildBlockRelease(llvm::Value *DeclPtr, BlockFieldFlags flags,
bool CanThrow);
class AutoVarEmission;
void emitByrefStructureInit(const AutoVarEmission &emission);
/// Enter a cleanup to destroy a __block variable. Note that this
/// cleanup should be a no-op if the variable hasn't left the stack
/// yet; if a cleanup is required for the variable itself, that needs
/// to be done externally.
/// \param Kind Cleanup kind.
/// \param Addr When \p LoadBlockVarAddr is false, the address of the __block
/// structure that will be passed to _Block_object_dispose. When
/// \p LoadBlockVarAddr is true, the address of the field of the block
/// structure that holds the address of the __block structure.
/// \param Flags The flag that will be passed to _Block_object_dispose.
/// \param LoadBlockVarAddr Indicates whether we need to emit a load from
/// \p Addr to get the address of the __block structure.
void enterByrefCleanup(CleanupKind Kind, Address Addr, BlockFieldFlags Flags,
bool LoadBlockVarAddr, bool CanThrow);
void setBlockContextParameter(const ImplicitParamDecl *D, unsigned argNum,
llvm::Value *ptr);
Address LoadBlockStruct();
Address GetAddrOfBlockDecl(const VarDecl *var);
/// BuildBlockByrefAddress - Computes the location of the
/// data in a variable which is declared as __block.
Address emitBlockByrefAddress(Address baseAddr, const VarDecl *V,
bool followForward = true);
Address emitBlockByrefAddress(Address baseAddr,
const BlockByrefInfo &info,
bool followForward,
const llvm::Twine &name);
const BlockByrefInfo &getBlockByrefInfo(const VarDecl *var);
QualType BuildFunctionArgList(GlobalDecl GD, FunctionArgList &Args);
void GenerateCode(GlobalDecl GD, llvm::Function *Fn,
const CGFunctionInfo &FnInfo);
/// Annotate the function with an attribute that disables TSan checking at
/// runtime.
void markAsIgnoreThreadCheckingAtRuntime(llvm::Function *Fn);
/// Emit code for the start of a function.
/// \param Loc The location to be associated with the function.
/// \param StartLoc The location of the function body.
void StartFunction(GlobalDecl GD,
QualType RetTy,
llvm::Function *Fn,
const CGFunctionInfo &FnInfo,
const FunctionArgList &Args,
SourceLocation Loc = SourceLocation(),
SourceLocation StartLoc = SourceLocation());
static bool IsConstructorDelegationValid(const CXXConstructorDecl *Ctor);
void EmitConstructorBody(FunctionArgList &Args);
void EmitDestructorBody(FunctionArgList &Args);
void emitImplicitAssignmentOperatorBody(FunctionArgList &Args);
void EmitFunctionBody(const Stmt *Body);
void EmitBlockWithFallThrough(llvm::BasicBlock *BB, const Stmt *S);
void EmitForwardingCallToLambda(const CXXMethodDecl *LambdaCallOperator,
CallArgList &CallArgs);
void EmitLambdaBlockInvokeBody();
void EmitLambdaDelegatingInvokeBody(const CXXMethodDecl *MD);
void EmitLambdaStaticInvokeBody(const CXXMethodDecl *MD);
void EmitLambdaVLACapture(const VariableArrayType *VAT, LValue LV) {
EmitStoreThroughLValue(RValue::get(VLASizeMap[VAT->getSizeExpr()]), LV);
void EmitAsanPrologueOrEpilogue(bool Prologue);
/// Emit the unified return block, trying to avoid its emission when
/// possible.
/// \return The debug location of the user written return statement if the
/// return block is is avoided.
llvm::DebugLoc EmitReturnBlock();
/// FinishFunction - Complete IR generation of the current function. It is
/// legal to call this function even if there is no current insertion point.
void FinishFunction(SourceLocation EndLoc=SourceLocation());
void StartThunk(llvm::Function *Fn, GlobalDecl GD,
const CGFunctionInfo &FnInfo, bool IsUnprototyped);
void EmitCallAndReturnForThunk(llvm::FunctionCallee Callee,
const ThunkInfo *Thunk, bool IsUnprototyped);
void FinishThunk();
/// Emit a musttail call for a thunk with a potentially adjusted this pointer.
void EmitMustTailThunk(GlobalDecl GD, llvm::Value *AdjustedThisPtr,
llvm::FunctionCallee Callee);
/// Generate a thunk for the given method.
void generateThunk(llvm::Function *Fn, const CGFunctionInfo &FnInfo,
GlobalDecl GD, const ThunkInfo &Thunk,
bool IsUnprototyped);
llvm::Function *GenerateVarArgsThunk(llvm::Function *Fn,
const CGFunctionInfo &FnInfo,
GlobalDecl GD, const ThunkInfo &Thunk);
void EmitCtorPrologue(const CXXConstructorDecl *CD, CXXCtorType Type,
FunctionArgList &Args);
void EmitInitializerForField(FieldDecl *Field, LValue LHS, Expr *Init);
/// Struct with all information about dynamic [sub]class needed to set vptr.
struct VPtr {
BaseSubobject Base;
const CXXRecordDecl *NearestVBase;
CharUnits OffsetFromNearestVBase;
const CXXRecordDecl *VTableClass;
/// Initialize the vtable pointer of the given subobject.
void InitializeVTablePointer(const VPtr &vptr);
typedef llvm::SmallVector<VPtr, 4> VPtrsVector;
typedef llvm::SmallPtrSet<const CXXRecordDecl *, 4> VisitedVirtualBasesSetTy;
VPtrsVector getVTablePointers(const CXXRecordDecl *VTableClass);
void getVTablePointers(BaseSubobject Base, const CXXRecordDecl *NearestVBase,
CharUnits OffsetFromNearestVBase,
bool BaseIsNonVirtualPrimaryBase,
const CXXRecordDecl *VTableClass,
VisitedVirtualBasesSetTy &VBases, VPtrsVector &vptrs);
void InitializeVTablePointers(const CXXRecordDecl *ClassDecl);
/// GetVTablePtr - Return the Value of the vtable pointer member pointed
/// to by This.
llvm::Value *GetVTablePtr(Address This, llvm::Type *VTableTy,
const CXXRecordDecl *VTableClass);
enum CFITypeCheckKind {
/// Derived is the presumed address of an object of type T after a
/// cast. If T is a polymorphic class type, emit a check that the virtual
/// table for Derived belongs to a class derived from T.
void EmitVTablePtrCheckForCast(QualType T, llvm::Value *Derived,
bool MayBeNull, CFITypeCheckKind TCK,
SourceLocation Loc);
/// EmitVTablePtrCheckForCall - Virtual method MD is being called via VTable.
/// If vptr CFI is enabled, emit a check that VTable is valid.
void EmitVTablePtrCheckForCall(const CXXRecordDecl *RD, llvm::Value *VTable,
CFITypeCheckKind TCK, SourceLocation Loc);
/// EmitVTablePtrCheck - Emit a check that VTable is a valid virtual table for
/// RD using llvm.type.test.
void EmitVTablePtrCheck(const CXXRecordDecl *RD, llvm::Value *VTable,
CFITypeCheckKind TCK, SourceLocation Loc);
/// If whole-program virtual table optimization is enabled, emit an assumption
/// that VTable is a member of RD's type identifier. Or, if vptr CFI is
/// enabled, emit a check that VTable is a member of RD's type identifier.
void EmitTypeMetadataCodeForVCall(const CXXRecordDecl *RD,
llvm::Value *VTable, SourceLocation Loc);
/// Returns whether we should perform a type checked load when loading a
/// virtual function for virtual calls to members of RD. This is generally
/// true when both vcall CFI and whole-program-vtables are enabled.
bool ShouldEmitVTableTypeCheckedLoad(const CXXRecordDecl *RD);
/// Emit a type checked load from the given vtable.
llvm::Value *EmitVTableTypeCheckedLoad(const CXXRecordDecl *RD, llvm::Value *VTable,
uint64_t VTableByteOffset);
/// EnterDtorCleanups - Enter the cleanups necessary to complete the
/// given phase of destruction for a destructor. The end result
/// should call destructors on members and base classes in reverse
/// order of their construction.
void EnterDtorCleanups(const CXXDestructorDecl *Dtor, CXXDtorType Type);
/// ShouldInstrumentFunction - Return true if the current function should be
/// instrumented with __cyg_profile_func_* calls
bool ShouldInstrumentFunction();
/// ShouldXRayInstrument - Return true if the current function should be
/// instrumented with XRay nop sleds.
bool ShouldXRayInstrumentFunction() const;
/// AlwaysEmitXRayCustomEvents - Return true if we must unconditionally emit
/// XRay custom event handling calls.
bool AlwaysEmitXRayCustomEvents() const;
/// AlwaysEmitXRayTypedEvents - Return true if clang must unconditionally emit
/// XRay typed event handling calls.
bool AlwaysEmitXRayTypedEvents() const;
/// Encode an address into a form suitable for use in a function prologue.
llvm::Constant *EncodeAddrForUseInPrologue(llvm::Function *F,
llvm::Constant *Addr);
/// Decode an address used in a function prologue, encoded by \c
/// EncodeAddrForUseInPrologue.
llvm::Value *DecodeAddrUsedInPrologue(llvm::Value *F,
llvm::Value *EncodedAddr);
/// EmitFunctionProlog - Emit the target specific LLVM code to load the
/// arguments for the given function. This is also responsible for naming the
/// LLVM function arguments.
void EmitFunctionProlog(const CGFunctionInfo &FI,
llvm::Function *Fn,
const FunctionArgList &Args);
/// EmitFunctionEpilog - Emit the target specific LLVM code to return the
/// given temporary.
void EmitFunctionEpilog(const CGFunctionInfo &FI, bool EmitRetDbgLoc,
SourceLocation EndLoc);
/// Emit a test that checks if the return value \p RV is nonnull.
void EmitReturnValueCheck(llvm::Value *RV);
/// EmitStartEHSpec - Emit the start of the exception spec.
void EmitStartEHSpec(const Decl *D);
/// EmitEndEHSpec - Emit the end of the exception spec.
void EmitEndEHSpec(const Decl *D);
/// getTerminateLandingPad - Return a landing pad that just calls terminate.
llvm::BasicBlock *getTerminateLandingPad();
/// getTerminateLandingPad - Return a cleanup funclet that just calls
/// terminate.
llvm::BasicBlock *getTerminateFunclet();
/// getTerminateHandler - Return a handler (not a landing pad, just
/// a catch handler) that just calls terminate. This is used when
/// a terminate scope encloses a try.
llvm::BasicBlock *getTerminateHandler();
llvm::Type *ConvertTypeForMem(QualType T);
llvm::Type *ConvertType(QualType T);
llvm::Type *ConvertType(const TypeDecl *T) {
return ConvertType(getContext().getTypeDeclType(T));
/// LoadObjCSelf - Load the value of self. This function is only valid while
/// generating code for an Objective-C method.
llvm::Value *LoadObjCSelf();
/// TypeOfSelfObject - Return type of object that this self represents.
QualType TypeOfSelfObject();
/// getEvaluationKind - Return the TypeEvaluationKind of QualType \c T.
static TypeEvaluationKind getEvaluationKind(QualType T);
static bool hasScalarEvaluationKind(QualType T) {
return getEvaluationKind(T) == TEK_Scalar;
static bool hasAggregateEvaluationKind(QualType T) {
return getEvaluationKind(T) == TEK_Aggregate;
/// createBasicBlock - Create an LLVM basic block.
llvm::BasicBlock *createBasicBlock(const Twine &name = "",
llvm::Function *parent = nullptr,
llvm::BasicBlock *before = nullptr) {
return llvm::BasicBlock::Create(getLLVMContext(), name, parent, before);
/// getBasicBlockForLabel - Return the LLVM basicblock that the specified
/// label maps to.
JumpDest getJumpDestForLabel(const LabelDecl *S);
/// SimplifyForwardingBlocks - If the given basic block is only a branch to
/// another basic block, simplify it. This assumes that no other code could
/// potentially reference the basic block.
void SimplifyForwardingBlocks(llvm::BasicBlock *BB);
/// EmitBlock - Emit the given block \arg BB and set it as the insert point,
/// adding a fall-through branch from the current insert block if
/// necessary. It is legal to call this function even if there is no current
/// insertion point.
/// IsFinished - If true, indicates that the caller has finished emitting
/// branches to the given block and does not expect to emit code into it. This
/// means the block can be ignored if it is unreachable.
void EmitBlock(llvm::BasicBlock *BB, bool IsFinished=false);
/// EmitBlockAfterUses - Emit the given block somewhere hopefully
/// near its uses, and leave the insertion point in it.
void EmitBlockAfterUses(llvm::BasicBlock *BB);
/// EmitBranch - Emit a branch to the specified basic block from the current
/// insert block, taking care to avoid creation of branches from dummy
/// blocks. It is legal to call this function even if there is no current
/// insertion point.
/// This function clears the current insertion point. The caller should follow
/// calls to this function with calls to Emit*Block prior to generation new
/// code.
void EmitBranch(llvm::BasicBlock *Block);
/// HaveInsertPoint - True if an insertion point is defined. If not, this
/// indicates that the current code being emitted is unreachable.
bool HaveInsertPoint() const {
return Builder.GetInsertBlock() != nullptr;
/// EnsureInsertPoint - Ensure that an insertion point is defined so that
/// emitted IR has a place to go. Note that by definition, if this function
/// creates a block then that block is unreachable; callers may do better to
/// detect when no insertion point is defined and simply skip IR generation.
void EnsureInsertPoint() {
if (!HaveInsertPoint())
/// ErrorUnsupported - Print out an error that codegen doesn't support the
/// specified stmt yet.
void ErrorUnsupported(const Stmt *S, const char *Type);
// Helpers
LValue MakeAddrLValue(Address Addr, QualType T,
AlignmentSource Source = AlignmentSource::Type) {
return LValue::MakeAddr(Addr, T, getContext(), LValueBaseInfo(Source),
LValue MakeAddrLValue(Address Addr, QualType T, LValueBaseInfo BaseInfo,
TBAAAccessInfo TBAAInfo) {
return LValue::MakeAddr(Addr, T, getContext(), BaseInfo, TBAAInfo);
LValue MakeAddrLValue(llvm::Value *V, QualType T, CharUnits Alignment,
AlignmentSource Source = AlignmentSource::Type) {
return LValue::MakeAddr(Address(V, Alignment), T, getContext(),
LValueBaseInfo(Source), CGM.getTBAAAccessInfo(T));
LValue MakeAddrLValue(llvm::Value *V, QualType T, CharUnits Alignment,
LValueBaseInfo BaseInfo, TBAAAccessInfo TBAAInfo) {
return LValue::MakeAddr(Address(V, Alignment), T, getContext(),
BaseInfo, TBAAInfo);
LValue MakeNaturalAlignPointeeAddrLValue(llvm::Value *V, QualType T);
LValue MakeNaturalAlignAddrLValue(llvm::Value *V, QualType T);
CharUnits getNaturalTypeAlignment(QualType T,
LValueBaseInfo *BaseInfo = nullptr,
TBAAAccessInfo *TBAAInfo = nullptr,
bool forPointeeType = false);
CharUnits getNaturalPointeeTypeAlignment(QualType T,
LValueBaseInfo *BaseInfo = nullptr,
TBAAAccessInfo *TBAAInfo = nullptr);
Address EmitLoadOfReference(LValue RefLVal,
LValueBaseInfo *PointeeBaseInfo = nullptr,
TBAAAccessInfo *PointeeTBAAInfo = nullptr);
LValue EmitLoadOfReferenceLValue(LValue RefLVal);
LValue EmitLoadOfReferenceLValue(Address RefAddr, QualType RefTy,
AlignmentSource Source =
AlignmentSource::Type) {
LValue RefLVal = MakeAddrLValue(RefAddr, RefTy, LValueBaseInfo(Source),
return EmitLoadOfReferenceLValue(RefLVal);
Address EmitLoadOfPointer(Address Ptr, const PointerType *PtrTy,
LValueBaseInfo *BaseInfo = nullptr,
TBAAAccessInfo *TBAAInfo = nullptr);
LValue EmitLoadOfPointerLValue(Address Ptr, const PointerType *PtrTy);
/// CreateTempAlloca - This creates an alloca and inserts it into the entry
/// block if \p ArraySize is nullptr, otherwise inserts it at the current
/// insertion point of the builder. The caller is responsible for setting an
/// appropriate alignment on
/// the alloca.
/// \p ArraySize is the number of array elements to be allocated if it
/// is not nullptr.
/// LangAS::Default is the address space of pointers to local variables and
/// temporaries, as exposed in the source language. In certain
/// configurations, this is not the same as the alloca address space, and a
/// cast is needed to lift the pointer from the alloca AS into
/// LangAS::Default. This can happen when the target uses a restricted
/// address space for the stack but the source language requires
/// LangAS::Default to be a generic address space. The latter condition is
/// common for most programming languages; OpenCL is an exception in that
/// LangAS::Default is the private address space, which naturally maps
/// to the stack.
/// Because the address of a temporary is often exposed to the program in
/// various ways, this function will perform the cast. The original alloca
/// instruction is returned through \p Alloca if it is not nullptr.
/// The cast is not performaed in CreateTempAllocaWithoutCast. This is
/// more efficient if the caller knows that the address will not be exposed.
llvm::AllocaInst *CreateTempAlloca(llvm::Type *Ty, const Twine &Name = "tmp",
llvm::Value *ArraySize = nullptr);
Address CreateTempAlloca(llvm::Type *Ty, CharUnits align,
const Twine &Name = "tmp",
llvm::Value *ArraySize = nullptr,
Address *Alloca = nullptr);
Address CreateTempAllocaWithoutCast(llvm::Type *Ty, CharUnits align,
const Twine &Name = "tmp",
llvm::Value *ArraySize = nullptr);
/// CreateDefaultAlignedTempAlloca - This creates an alloca with the
/// default ABI alignment of the given LLVM type.
/// IMPORTANT NOTE: This is *not* generally the right alignment for
/// any given AST type that happens to have been lowered to the
/// given IR type. This should only ever be used for function-local,
/// IR-driven manipulations like saving and restoring a value. Do
/// not hand this address off to arbitrary IRGen routines, and especially
/// do not pass it as an argument to a function that might expect a
/// properly ABI-aligned value.
Address CreateDefaultAlignTempAlloca(llvm::Type *Ty,
const Twine &Name = "tmp");
/// InitTempAlloca - Provide an initial value for the given alloca which
/// will be observable at all locations in the function.
/// The address should be something that was returned from one of
/// the CreateTempAlloca or CreateMemTemp routines, and the
/// initializer must be valid in the entry block (i.e. it must
/// either be a constant or an argument value).
void InitTempAlloca(Address Alloca, llvm::Value *Value);
/// CreateIRTemp - Create a temporary IR object of the given type, with
/// appropriate alignment. This routine should only be used when an temporary
/// value needs to be stored into an alloca (for example, to avoid explicit
/// PHI construction), but the type is the IR type, not the type appropriate
/// for storing in memory.
/// That is, this is exactly equivalent to CreateMemTemp, but calling
/// ConvertType instead of ConvertTypeForMem.
Address CreateIRTemp(QualType T, const Twine &Name = "tmp");
/// CreateMemTemp - Create a temporary memory object of the given type, with
/// appropriate alignmen and cast it to the default address space. Returns
/// the original alloca instruction by \p Alloca if it is not nullptr.
Address CreateMemTemp(QualType T, const Twine &Name = "tmp",
Address *Alloca = nullptr);
Address CreateMemTemp(QualType T, CharUnits Align, const Twine &Name = "tmp",
Address *Alloca = nullptr);
/// CreateMemTemp - Create a temporary memory object of the given type, with
/// appropriate alignmen without casting it to the default address space.
Address CreateMemTempWithoutCast(QualType T, const Twine &Name = "tmp");
Address CreateMemTempWithoutCast(QualType T, CharUnits Align,
const Twine &Name = "tmp");
/// CreateAggTemp - Create a temporary memory object for the given
/// aggregate type.
AggValueSlot CreateAggTemp(QualType T, const Twine &Name = "tmp") {
return AggValueSlot::forAddr(CreateMemTemp(T, Name),
/// Emit a cast to void* in the appropriate address space.
llvm::Value *EmitCastToVoidPtr(llvm::Value *value);
/// EvaluateExprAsBool - Perform the usual unary conversions on the specified
/// expression and compare the result against zero, returning an Int1Ty value.
llvm::Value *EvaluateExprAsBool(const Expr *E);
/// EmitIgnoredExpr - Emit an expression in a context which ignores the result.
void EmitIgnoredExpr(const Expr *E);
/// EmitAnyExpr - Emit code to compute the specified expression which can have
/// any type. The result is returned as an RValue struct. If this is an
/// aggregate expression, the aggloc/agglocvolatile arguments indicate where
/// the result should be returned.
/// \param ignoreResult True if the resulting value isn't used.
RValue EmitAnyExpr(const Expr *E,
AggValueSlot aggSlot = AggValueSlot::ignored(),
bool ignoreResult = false);
// EmitVAListRef - Emit a "reference" to a va_list; this is either the address
// or the value of the expression, depending on how va_list is defined.
Address EmitVAListRef(const Expr *E);
/// Emit a "reference" to a __builtin_ms_va_list; this is
/// always the value of the expression, because a __builtin_ms_va_list is a
/// pointer to a char.
Address EmitMSVAListRef(const Expr *E);
/// EmitAnyExprToTemp - Similarly to EmitAnyExpr(), however, the result will
/// always be accessible even if no aggregate location is provided.
RValue EmitAnyExprToTemp(const Expr *E);
/// EmitAnyExprToMem - Emits the code necessary to evaluate an
/// arbitrary expression into the given memory location.
void EmitAnyExprToMem(const Expr *E, Address Location,
Qualifiers Quals, bool IsInitializer);
void EmitAnyExprToExn(const Expr *E, Address Addr);
/// EmitExprAsInit - Emits the code necessary to initialize a
/// location in memory with the given initializer.
void EmitExprAsInit(const Expr *init, const ValueDecl *D, LValue lvalue,
bool capturedByInit);
/// hasVolatileMember - returns true if aggregate type has a volatile
/// member.
bool hasVolatileMember(QualType T) {
if (const RecordType *RT = T->getAs<RecordType>()) {
const RecordDecl *RD = cast<RecordDecl>(RT->getDecl());
return RD->hasVolatileMember();
return false;
/// Determine whether a return value slot may overlap some other object.
AggValueSlot::Overlap_t getOverlapForReturnValue() {
// FIXME: Assuming no overlap here breaks guaranteed copy elision for base
// class subobjects. These cases may need to be revisited depending on the
// resolution of the relevant core issue.
return AggValueSlot::DoesNotOverlap;
/// Determine whether a field initialization may overlap some other object.
AggValueSlot::Overlap_t getOverlapForFieldInit(const FieldDecl *FD);
/// Determine whether a base class initialization may overlap some other
/// object.
AggValueSlot::Overlap_t getOverlapForBaseInit(const CXXRecordDecl *RD,
const CXXRecordDecl *BaseRD,
bool IsVirtual);
/// Emit an aggregate assignment.
void EmitAggregateAssign(LValue Dest, LValue Src, QualType EltTy) {
bool IsVolatile = hasVolatileMember(EltTy);
EmitAggregateCopy(Dest, Src, EltTy, AggValueSlot::MayOverlap, IsVolatile);
void EmitAggregateCopyCtor(LValue Dest, LValue Src,
AggValueSlot::Overlap_t MayOverlap) {
EmitAggregateCopy(Dest, Src, Src.getType(), MayOverlap);
/// EmitAggregateCopy - Emit an aggregate copy.
/// \param isVolatile \c true iff either the source or the destination is
/// volatile.
/// \param MayOverlap Whether the tail padding of the destination might be
/// occupied by some other object. More efficient code can often be
/// generated if not.
void EmitAggregateCopy(LValue Dest, LValue Src, QualType EltTy,
AggValueSlot::Overlap_t MayOverlap,
bool isVolatile = false);
/// GetAddrOfLocalVar - Return the address of a local variable.
Address GetAddrOfLocalVar(const VarDecl *VD) {
auto it = LocalDeclMap.find(VD);
assert(it != LocalDeclMap.end() &&
"Invalid argument to GetAddrOfLocalVar(), no decl!");
return it->second;
/// Given an opaque value expression, return its LValue mapping if it exists,
/// otherwise create one.
LValue getOrCreateOpaqueLValueMapping(const OpaqueValueExpr *e);
/// Given an opaque value expression, return its RValue mapping if it exists,
/// otherwise create one.
RValue getOrCreateOpaqueRValueMapping(const OpaqueValueExpr *e);
/// Get the index of the current ArrayInitLoopExpr, if any.
llvm::Value *getArrayInitIndex() { return ArrayInitIndex; }
/// getAccessedFieldNo - Given an encoded value and a result number, return
/// the input field number being accessed.
static unsigned getAccessedFieldNo(unsigned Idx, const llvm::Constant *Elts);
llvm::BlockAddress *GetAddrOfLabel(const LabelDecl *L);
llvm::BasicBlock *GetIndirectGotoBlock();
/// Check if \p E is a C++ "this" pointer wrapped in value-preserving casts.
static bool IsWrappedCXXThis(const Expr *E);
/// EmitNullInitialization - Generate code to set a value of the given type to
/// null, If the type contains data member pointers, they will be initialized
/// to -1 in accordance with the Itanium C++ ABI.
void EmitNullInitialization(Address DestPtr, QualType Ty);
/// Emits a call to an LLVM variable-argument intrinsic, either
/// \c llvm.va_start or \c llvm.va_end.
/// \param ArgValue A reference to the \c va_list as emitted by either
/// \c EmitVAListRef or \c EmitMSVAListRef.
/// \param IsStart If \c true, emits a call to \c llvm.va_start; otherwise,
/// calls \c llvm.va_end.
llvm::Value *EmitVAStartEnd(llvm::Value *ArgValue, bool IsStart);
/// Generate code to get an argument from the passed in pointer
/// and update it accordingly.
/// \param VE The \c VAArgExpr for which to generate code.
/// \param VAListAddr Receives a reference to the \c va_list as emitted by
/// either \c EmitVAListRef or \c EmitMSVAListRef.
/// \returns A pointer to the argument.
// FIXME: We should be able to get rid of this method and use the va_arg
// instruction in LLVM instead once it works well enough.
Address EmitVAArg(VAArgExpr *VE, Address &VAListAddr);
/// emitArrayLength - Compute the length of an array, even if it's a
/// VLA, and drill down to the base element type.
llvm::Value *emitArrayLength(const ArrayType *arrayType,
QualType &baseType,
Address &addr);
/// EmitVLASize - Capture all the sizes for the VLA expressions in
/// the given variably-modified type and store them in the VLASizeMap.
/// This function can be called with a null (unreachable) insert point.
void EmitVariablyModifiedType(QualType Ty);
struct VlaSizePair {
llvm::Value *NumElts;
QualType Type;
VlaSizePair(llvm::Value *NE, QualType T) : NumElts(NE), Type(T) {}
/// Return the number of elements for a single dimension
/// for the given array type.
VlaSizePair getVLAElements1D(const VariableArrayType *vla);
VlaSizePair getVLAElements1D(QualType vla);
/// Returns an LLVM value that corresponds to the size,
/// in non-variably-sized elements, of a variable length array type,
/// plus that largest non-variably-sized element type. Assumes that
/// the type has already been emitted with EmitVariablyModifiedType.
VlaSizePair getVLASize(const VariableArrayType *vla);
VlaSizePair getVLASize(QualType vla);
/// LoadCXXThis - Load the value of 'this'. This function is only valid while
/// generating code for an C++ member function.
llvm::Value *LoadCXXThis() {
assert(CXXThisValue && "no 'this' value for this function");
return CXXThisValue;
Address LoadCXXThisAddress();
/// LoadCXXVTT - Load the VTT parameter to base constructors/destructors have
/// virtual bases.
// FIXME: Every place that calls LoadCXXVTT is something
// that needs to be abstracted properly.
llvm::Value *LoadCXXVTT() {
assert(CXXStructorImplicitParamValue && "no VTT value for this function");
return CXXStructorImplicitParamValue;
/// GetAddressOfBaseOfCompleteClass - Convert the given pointer to a
/// complete class to the given direct base.
GetAddressOfDirectBaseInCompleteClass(Address Value,
const CXXRecordDecl *Derived,
const CXXRecordDecl *Base,
bool BaseIsVirtual);
static bool ShouldNullCheckClassCastValue(const CastExpr *Cast);
/// GetAddressOfBaseClass - This function will add the necessary delta to the
/// load of 'this' and returns address of the base class.
Address GetAddressOfBaseClass(Address Value,
const CXXRecordDecl *Derived,
CastExpr::path_const_iterator PathBegin,
CastExpr::path_const_iterator PathEnd,
bool NullCheckValue, SourceLocation Loc);
Address GetAddressOfDerivedClass(Address Value,
const CXXRecordDecl *Derived,
CastExpr::path_const_iterator PathBegin,
CastExpr::path_const_iterator PathEnd,
bool NullCheckValue);
/// GetVTTParameter - Return the VTT parameter that should be passed to a
/// base constructor/destructor with virtual bases.
/// FIXME: VTTs are Itanium ABI-specific, so the definition should move
/// to ItaniumCXXABI.cpp together with all the references to VTT.
llvm::Value *GetVTTParameter(GlobalDecl GD, bool ForVirtualBase,
bool Delegating);
void EmitDelegateCXXConstructorCall(const CXXConstructorDecl *Ctor,
CXXCtorType CtorType,
const FunctionArgList &Args,
SourceLocation Loc);
// It's important not to confuse this and the previous function. Delegating
// constructors are the C++0x feature. The constructor delegate optimization
// is used to reduce duplication in the base and complete consturctors where
// they are substantially the same.
void EmitDelegatingCXXConstructorCall(const CXXConstructorDecl *Ctor,
const FunctionArgList &Args);
/// Emit a call to an inheriting constructor (that is, one that invokes a
/// constructor inherited from a base class) by inlining its definition. This
/// is necessary if the ABI does not support forwarding the arguments to the
/// base class constructor (because they're variadic or similar).
void EmitInlinedInheritingCXXConstructorCall(const CXXConstructorDecl *Ctor,
CXXCtorType CtorType,
bool ForVirtualBase,
bool Delegating,
CallArgList &Args);
/// Emit a call to a constructor inherited from a base class, passing the
/// current constructor's arguments along unmodified (without even making
/// a copy).
void EmitInheritedCXXConstructorCall(const CXXConstructorDecl *D,
bool ForVirtualBase, Address This,
bool InheritedFromVBase,
const CXXInheritedCtorInitExpr *E);
void EmitCXXConstructorCall(const CXXConstructorDecl *D, CXXCtorType Type,
bool ForVirtualBase, bool Delegating,
AggValueSlot ThisAVS, const CXXConstructExpr *E);
void EmitCXXConstructorCall(const CXXConstructorDecl *D, CXXCtorType Type,
bool ForVirtualBase, bool Delegating,
Address This, CallArgList &Args,
AggValueSlot::Overlap_t Overlap,
SourceLocation Loc, bool NewPointerIsChecked);
/// Emit assumption load for all bases. Requires to be be called only on
/// most-derived class and not under construction of the object.
void EmitVTableAssumptionLoads(const CXXRecordDecl *ClassDecl, Address This);
/// Emit assumption that vptr load == global vtable.
void EmitVTableAssumptionLoad(const VPtr &vptr, Address This);
void EmitSynthesizedCXXCopyCtorCall(const CXXConstructorDecl *D,
Address This, Address Src,
const CXXConstructExpr *E);
void EmitCXXAggrConstructorCall(const CXXConstructorDecl *D,
const ArrayType *ArrayTy,
Address ArrayPtr,
const CXXConstructExpr *E,
bool NewPointerIsChecked,
bool ZeroInitialization = false);
void EmitCXXAggrConstructorCall(const CXXConstructorDecl *D,
llvm::Value *NumElements,
Address ArrayPtr,
const CXXConstructExpr *E,
bool NewPointerIsChecked,
bool ZeroInitialization = false);
static Destroyer destroyCXXObject;
void EmitCXXDestructorCall(const CXXDestructorDecl *D, CXXDtorType Type,
bool ForVirtualBase, bool Delegating, Address This,
QualType ThisTy);
void EmitNewArrayInitializer(const CXXNewExpr *E, QualType elementType,
llvm::Type *ElementTy, Address NewPtr,
llvm::Value *NumElements,
llvm::Value *AllocSizeWithoutCookie);
void EmitCXXTemporary(const CXXTemporary *Temporary, QualType TempType,
Address Ptr);
llvm::Value *EmitLifetimeStart(uint64_t Size, llvm::Value *Addr);
void EmitLifetimeEnd(llvm::Value *Size, llvm::Value *Addr);
llvm::Value *EmitCXXNewExpr(const CXXNewExpr *E);
void EmitCXXDeleteExpr(const CXXDeleteExpr *E);
void EmitDeleteCall(const FunctionDecl *DeleteFD, llvm::Value *Ptr,
QualType DeleteTy, llvm::Value *NumElements = nullptr,
CharUnits CookieSize = CharUnits());
RValue EmitBuiltinNewDeleteCall(const FunctionProtoType *Type,
const CallExpr *TheCallExpr, bool IsDelete);
llvm::Value *EmitCXXTypeidExpr(const CXXTypeidExpr *E);
llvm::Value *EmitDynamicCast(Address V, const CXXDynamicCastExpr *DCE);
Address EmitCXXUuidofExpr(const CXXUuidofExpr *E);
/// Situations in which we might emit a check for the suitability of a
/// pointer or glvalue.
enum TypeCheckKind {
/// Checking the operand of a load. Must be suitably sized and aligned.
/// Checking the destination of a store. Must be suitably sized and aligned.
/// Checking the bound value in a reference binding. Must be suitably sized
/// and aligned, but is not required to refer to an object (until the
/// reference is used), per core issue 453.
/// Checking the object expression in a non-static data member access. Must
/// be an object within its lifetime.
/// Checking the 'this' pointer for a call to a non-static member function.
/// Must be an object within its lifetime.
/// Checking the 'this' pointer for a constructor call.
/// Checking the operand of a static_cast to a derived pointer type. Must be
/// null or an object within its lifetime.
/// Checking the operand of a static_cast to a derived reference type. Must
/// be an object within its lifetime.
/// Checking the operand of a cast to a base object. Must be suitably sized
/// and aligned.
/// Checking the operand of a cast to a virtual base object. Must be an
/// object within its lifetime.
/// Checking the value assigned to a _Nonnull pointer. Must not be null.
/// Checking the operand of a dynamic_cast or a typeid expression. Must be
/// null or an object within its lifetime.
/// Determine whether the pointer type check \p TCK permits null pointers.
static bool isNullPointerAllowed(TypeCheckKind TCK);
/// Determine whether the pointer type check \p TCK requires a vptr check.
static bool isVptrCheckRequired(TypeCheckKind TCK, QualType Ty);
/// Whether any type-checking sanitizers are enabled. If \c false,
/// calls to EmitTypeCheck can be skipped.
bool sanitizePerformTypeCheck() const;
/// Emit a check that \p V is the address of storage of the
/// appropriate size and alignment for an object of type \p Type
/// (or if ArraySize is provided, for an array of that bound).
void EmitTypeCheck(TypeCheckKind TCK, SourceLocation Loc, llvm::Value *V,
QualType Type, CharUnits Alignment = CharUnits::Zero(),
SanitizerSet SkippedChecks = SanitizerSet(),
llvm::Value *ArraySize = nullptr);
/// Emit a check that \p Base points into an array object, which
/// we can access at index \p Index. \p Accessed should be \c false if we
/// this expression is used as an lvalue, for instance in "&Arr[Idx]".
void EmitBoundsCheck(const Expr *E, const Expr *Base, llvm::Value *Index,
QualType IndexType, bool Accessed);
llvm::Value *EmitScalarPrePostIncDec(const UnaryOperator *E, LValue LV,
bool isInc, bool isPre);
ComplexPairTy EmitComplexPrePostIncDec(const UnaryOperator *E, LValue LV,
bool isInc, bool isPre);
/// Converts Location to a DebugLoc, if debug information is enabled.
llvm::DebugLoc SourceLocToDebugLoc(SourceLocation Location);
/// Get the record field index as represented in debug info.
unsigned getDebugInfoFIndex(const RecordDecl *Rec, unsigned FieldIndex);
// Declaration Emission
/// EmitDecl - Emit a declaration.
/// This function can be called with a null (unreachable) insert point.
void EmitDecl(const Decl &D);
/// EmitVarDecl - Emit a local variable declaration.
/// This function can be called with a null (unreachable) insert point.
void EmitVarDecl(const VarDecl &D);
void EmitScalarInit(const Expr *init, const ValueDecl *D, LValue lvalue,
bool capturedByInit);
typedef void SpecialInitFn(CodeGenFunction &Init, const VarDecl &D,
llvm::Value *Address);
/// Determine whether the given initializer is trivial in the sense
/// that it requires no code to be generated.
bool isTrivialInitializer(const Expr *Init);
/// EmitAutoVarDecl - Emit an auto variable declaration.
/// This function can be called with a null (unreachable) insert point.
void EmitAutoVarDecl(const VarDecl &D);
class AutoVarEmission {
friend class CodeGenFunction;
const VarDecl *Variable;
/// The address of the alloca for languages with explicit address space
/// (e.g. OpenCL) or alloca casted to generic pointer for address space
/// agnostic languages (e.g. C++). Invalid if the variable was emitted
/// as a global constant.
Address Addr;
llvm::Value *NRVOFlag;
/// True if the variable is a __block variable that is captured by an
/// escaping block.
bool IsEscapingByRef;
/// True if the variable is of aggregate type and has a constant
/// initializer.
bool IsConstantAggregate;
/// Non-null if we should use lifetime annotations.
llvm::Value *SizeForLifetimeMarkers;
/// Address with original alloca instruction. Invalid if the variable was
/// emitted as a global constant.
Address AllocaAddr;
struct Invalid {};
: Variable(nullptr), Addr(Address::invalid()),
AllocaAddr(Address::invalid()) {}
AutoVarEmission(const VarDecl &variable)
: Variable(&variable), Addr(Address::invalid()), NRVOFlag(nullptr),
IsEscapingByRef(false), IsConstantAggregate(false),
SizeForLifetimeMarkers(nullptr), AllocaAddr(Address::invalid()) {}
bool wasEmittedAsGlobal() const { return !Addr.isValid(); }
static AutoVarEmission invalid() { return AutoVarEmission(Invalid()); }
bool useLifetimeMarkers() const {
return SizeForLifetimeMarkers != nullptr;
llvm::Value *getSizeForLifetimeMarkers() const {
return SizeForLifetimeMarkers;
/// Returns the raw, allocated address, which is not necessarily
/// the address of the object itself. It is casted to default
/// address space for address space agnostic languages.
Address getAllocatedAddress() const {
return Addr;
/// Returns the address for the original alloca instruction.
Address getOriginalAllocatedAddress() const { return AllocaAddr; }
/// Returns the address of the object within this declaration.
/// Note that this does not chase the forwarding pointer for
/// __block decls.
Address getObjectAddress(CodeGenFunction &CGF) const {
if (!IsEscapingByRef) return Addr;
return CGF.emitBlockByrefAddress(Addr, Variable, /*forward*/ false);
AutoVarEmission EmitAutoVarAlloca(const VarDecl &var);
void EmitAutoVarInit(const AutoVarEmission &emission);
void EmitAutoVarCleanups(const AutoVarEmission &emission);
void emitAutoVarTypeCleanup(const AutoVarEmission &emission,
QualType::DestructionKind dtorKind);
/// Emits the alloca and debug information for the size expressions for each
/// dimension of an array. It registers the association of its (1-dimensional)
/// QualTypes and size expression's debug node, so that CGDebugInfo can
/// reference this node when creating the DISubrange object to describe the
/// array types.
void EmitAndRegisterVariableArrayDimensions(CGDebugInfo *DI,
const VarDecl &D,
bool EmitDebugInfo);
void EmitStaticVarDecl(const VarDecl &D,
llvm::GlobalValue::LinkageTypes Linkage);
class ParamValue {
llvm::Value *Value;
unsigned Alignment;
ParamValue(llvm::Value *V, unsigned A) : Value(V), Alignment(A) {}
static ParamValue forDirect(llvm::Value *value) {
return ParamValue(value, 0);
static ParamValue forIndirect(Address addr) {
return ParamValue(addr.getPointer(), addr.getAlignment().getQuantity());
bool isIndirect() const { return Alignment != 0; }
llvm::Value *getAnyValue() const { return Value; }
llvm::Value *getDirectValue() const {
return Value;
Address getIndirectAddress() const {
return Address(Value, CharUnits::fromQuantity(Alignment));
/// EmitParmDecl - Emit a ParmVarDecl or an ImplicitParamDecl.
void EmitParmDecl(const VarDecl &D, ParamValue Arg, unsigned ArgNo);
/// protectFromPeepholes - Protect a value that we're intending to
/// store to the side, but which will probably be used later, from
/// aggressive peepholing optimizations that might delete it.
/// Pass the result to unprotectFromPeepholes to declare that
/// protection is no longer required.
/// There's no particular reason why this shouldn't apply to
/// l-values, it's just that no existing peepholes work on pointers.
PeepholeProtection protectFromPeepholes(RValue rvalue);
void unprotectFromPeepholes(PeepholeProtection protection);
void EmitAlignmentAssumptionCheck(llvm::Value *Ptr, QualType Ty,
SourceLocation Loc,
SourceLocation AssumptionLoc,
llvm::Value *Alignment,
llvm::Value *OffsetValue,
llvm::Value *TheCheck,
llvm::Instruction *Assumption);
void EmitAlignmentAssumption(llvm::Value *PtrValue, QualType Ty,
SourceLocation Loc, SourceLocation AssumptionLoc,
llvm::Value *Alignment,
llvm::Value *OffsetValue = nullptr);
void EmitAlignmentAssumption(llvm::Value *PtrValue, const Expr *E,
SourceLocation AssumptionLoc, llvm::Value *Alignment,
llvm::Value *OffsetValue = nullptr);
// Statement Emission
/// EmitStopPoint - Emit a debug stoppoint if we are emitting debug info.
void EmitStopPoint(const Stmt *S);
/// EmitStmt - Emit the code for the statement \arg S. It is legal to call
/// this function even if there is no current insertion point.
/// This function may clear the current insertion point; callers should use
/// EnsureInsertPoint if they wish to subsequently generate code without first
/// calling EmitBlock, EmitBranch, or EmitStmt.
void EmitStmt(const Stmt *S, ArrayRef<const Attr *> Attrs = None);
/// EmitSimpleStmt - Try to emit a "simple" statement which does not
/// necessarily require an insertion point or debug information; typically
/// because the statement amounts to a jump or a container of other
/// statements.
/// \return True if the statement was handled.
bool EmitSimpleStmt(const Stmt *S);
Address EmitCompoundStmt(const CompoundStmt &S, bool GetLast = false,
AggValueSlot AVS = AggValueSlot::ignored());
Address EmitCompoundStmtWithoutScope(const CompoundStmt &S,
bool GetLast = false,