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//===-- CodeGenFunction.h - Per-Function state for LLVM CodeGen -*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This is the internal per-function state used for llvm translation.
//
//===----------------------------------------------------------------------===//
#ifndef CLANG_CODEGEN_CODEGENFUNCTION_H
#define CLANG_CODEGEN_CODEGENFUNCTION_H
#include "clang/AST/Type.h"
#include "clang/AST/ExprCXX.h"
#include "clang/AST/ExprObjC.h"
#include "clang/Basic/TargetInfo.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/Support/ValueHandle.h"
#include <map>
#include "CodeGenModule.h"
#include "CGBlocks.h"
#include "CGBuilder.h"
#include "CGCall.h"
#include "CGCXX.h"
#include "CGValue.h"
namespace llvm {
class BasicBlock;
class LLVMContext;
class Module;
class SwitchInst;
class Twine;
class Value;
}
namespace clang {
class ASTContext;
class CXXDestructorDecl;
class CXXTryStmt;
class Decl;
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;
namespace CodeGen {
class CodeGenModule;
class CodeGenTypes;
class CGDebugInfo;
class CGFunctionInfo;
class CGRecordLayout;
/// CodeGenFunction - This class organizes the per-function state that is used
/// while generating LLVM code.
class CodeGenFunction : public BlockFunction {
CodeGenFunction(const CodeGenFunction&); // DO NOT IMPLEMENT
void operator=(const CodeGenFunction&); // DO NOT IMPLEMENT
public:
CodeGenModule &CGM; // Per-module state.
const TargetInfo &Target;
typedef std::pair<llvm::Value *, llvm::Value *> ComplexPairTy;
CGBuilderTy Builder;
/// CurFuncDecl - Holds the Decl for the current function or ObjC method.
/// This excludes BlockDecls.
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;
/// ReturnBlock - Unified return block.
llvm::BasicBlock *ReturnBlock;
/// ReturnValue - The temporary alloca to hold the return value. This is null
/// iff the function has no return value.
llvm::Instruction *ReturnValue;
/// AllocaInsertPoint - This is an instruction in the entry block before which
/// we prefer to insert allocas.
llvm::AssertingVH<llvm::Instruction> AllocaInsertPt;
const llvm::Type *LLVMIntTy;
uint32_t LLVMPointerWidth;
public:
/// ObjCEHValueStack - Stack of Objective-C exception values, used for
/// rethrows.
llvm::SmallVector<llvm::Value*, 8> ObjCEHValueStack;
/// PushCleanupBlock - Push a new cleanup entry on the stack and set the
/// passed in block as the cleanup block.
void PushCleanupBlock(llvm::BasicBlock *CleanupEntryBlock,
llvm::BasicBlock *CleanupExitBlock = 0,
bool EHOnly = false);
/// CleanupBlockInfo - A struct representing a popped cleanup block.
struct CleanupBlockInfo {
/// CleanupEntryBlock - the cleanup entry block
llvm::BasicBlock *CleanupBlock;
/// SwitchBlock - the block (if any) containing the switch instruction used
/// for jumping to the final destination.
llvm::BasicBlock *SwitchBlock;
/// EndBlock - the default destination for the switch instruction.
llvm::BasicBlock *EndBlock;
/// EHOnly - True iff this cleanup should only be performed on the
/// exceptional edge.
bool EHOnly;
CleanupBlockInfo(llvm::BasicBlock *cb, llvm::BasicBlock *sb,
llvm::BasicBlock *eb, bool ehonly = false)
: CleanupBlock(cb), SwitchBlock(sb), EndBlock(eb), EHOnly(ehonly) {}
};
/// PopCleanupBlock - Will pop the cleanup entry on the stack, process all
/// branch fixups and return a block info struct with the switch block and end
/// block.
CleanupBlockInfo PopCleanupBlock();
/// DelayedCleanupBlock - RAII object that will create a cleanup block and set
/// the insert point to that block. When destructed, it sets the insert point
/// to the previous block and pushes a new cleanup entry on the stack.
class DelayedCleanupBlock {
CodeGenFunction& CGF;
llvm::BasicBlock *CurBB;
llvm::BasicBlock *CleanupEntryBB;
llvm::BasicBlock *CleanupExitBB;
bool EHOnly;
public:
DelayedCleanupBlock(CodeGenFunction &cgf, bool ehonly = false)
: CGF(cgf), CurBB(CGF.Builder.GetInsertBlock()),
CleanupEntryBB(CGF.createBasicBlock("cleanup")), CleanupExitBB(0),
EHOnly(ehonly) {
CGF.Builder.SetInsertPoint(CleanupEntryBB);
}
llvm::BasicBlock *getCleanupExitBlock() {
if (!CleanupExitBB)
CleanupExitBB = CGF.createBasicBlock("cleanup.exit");
return CleanupExitBB;
}
~DelayedCleanupBlock() {
CGF.PushCleanupBlock(CleanupEntryBB, CleanupExitBB, EHOnly);
// FIXME: This is silly, move this into the builder.
if (CurBB)
CGF.Builder.SetInsertPoint(CurBB);
else
CGF.Builder.ClearInsertionPoint();
}
};
/// \brief Enters a new scope for capturing cleanups, all of which will be
/// executed once the scope is exited.
class CleanupScope {
CodeGenFunction& CGF;
size_t CleanupStackDepth;
bool OldDidCallStackSave;
bool PerformCleanup;
CleanupScope(const CleanupScope &); // DO NOT IMPLEMENT
CleanupScope &operator=(const CleanupScope &); // DO NOT IMPLEMENT
public:
/// \brief Enter a new cleanup scope.
explicit CleanupScope(CodeGenFunction &CGF)
: CGF(CGF), PerformCleanup(true)
{
CleanupStackDepth = CGF.CleanupEntries.size();
OldDidCallStackSave = CGF.DidCallStackSave;
}
/// \brief Exit this cleanup scope, emitting any accumulated
/// cleanups.
~CleanupScope() {
if (PerformCleanup) {
CGF.DidCallStackSave = OldDidCallStackSave;
CGF.EmitCleanupBlocks(CleanupStackDepth);
}
}
/// \brief Determine whether this scope requires any cleanups.
bool requiresCleanups() const {
return CGF.CleanupEntries.size() > CleanupStackDepth;
}
/// \brief Force the emission of cleanups now, instead of waiting
/// until this object is destroyed.
void ForceCleanup() {
assert(PerformCleanup && "Already forced cleanup");
CGF.DidCallStackSave = OldDidCallStackSave;
CGF.EmitCleanupBlocks(CleanupStackDepth);
PerformCleanup = false;
}
};
/// EmitCleanupBlocks - Takes the old cleanup stack size and emits the cleanup
/// blocks that have been added.
void EmitCleanupBlocks(size_t OldCleanupStackSize);
/// EmitBranchThroughCleanup - Emit a branch from the current insert block
/// through the cleanup handling code (if any) and then on to \arg Dest.
///
/// FIXME: Maybe this should really be in EmitBranch? Don't we always want
/// this behavior for branches?
void EmitBranchThroughCleanup(llvm::BasicBlock *Dest);
/// StartConditionalBranch - Should be called before a conditional part of an
/// expression is emitted. For example, before the RHS of the expression below
/// is emitted:
///
/// b && f(T());
///
/// This is used to make sure that any temporaries created in the conditional
/// branch are only destroyed if the branch is taken.
void StartConditionalBranch() {
++ConditionalBranchLevel;
}
/// FinishConditionalBranch - Should be called after a conditional part of an
/// expression has been emitted.
void FinishConditionalBranch() {
--ConditionalBranchLevel;
}
private:
CGDebugInfo *DebugInfo;
/// 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;
/// LocalDeclMap - This keeps track of the LLVM allocas or globals for local C
/// decls.
llvm::DenseMap<const Decl*, llvm::Value*> LocalDeclMap;
/// LabelMap - This keeps track of the LLVM basic block for each C label.
llvm::DenseMap<const LabelStmt*, llvm::BasicBlock*> LabelMap;
// BreakContinueStack - This keeps track of where break and continue
// statements should jump to.
struct BreakContinue {
BreakContinue(llvm::BasicBlock *bb, llvm::BasicBlock *cb)
: BreakBlock(bb), ContinueBlock(cb) {}
llvm::BasicBlock *BreakBlock;
llvm::BasicBlock *ContinueBlock;
};
llvm::SmallVector<BreakContinue, 8> BreakContinueStack;
/// SwitchInsn - This is nearest current switch instruction. It is null if if
/// current context is not in a switch.
llvm::SwitchInst *SwitchInsn;
/// CaseRangeBlock - This block holds if condition check for last case
/// statement range in current switch instruction.
llvm::BasicBlock *CaseRangeBlock;
/// InvokeDest - This is the nearest exception target for calls
/// which can unwind, when exceptions are being used.
llvm::BasicBlock *InvokeDest;
// 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;
/// DidCallStackSave - Whether llvm.stacksave has been called. Used to avoid
/// calling llvm.stacksave for multiple VLAs in the same scope.
bool DidCallStackSave;
struct CleanupEntry {
/// CleanupEntryBlock - The block of code that does the actual cleanup.
llvm::BasicBlock *CleanupEntryBlock;
/// CleanupExitBlock - The cleanup exit block.
llvm::BasicBlock *CleanupExitBlock;
/// Blocks - Basic blocks that were emitted in the current cleanup scope.
std::vector<llvm::BasicBlock *> Blocks;
/// BranchFixups - Branch instructions to basic blocks that haven't been
/// inserted into the current function yet.
std::vector<llvm::BranchInst *> BranchFixups;
/// EHOnly - Perform this only on the exceptional edge, not the main edge.
bool EHOnly;
explicit CleanupEntry(llvm::BasicBlock *CleanupEntryBlock,
llvm::BasicBlock *CleanupExitBlock, bool ehonly)
: CleanupEntryBlock(CleanupEntryBlock),
CleanupExitBlock(CleanupExitBlock),
EHOnly(ehonly) {}
};
/// CleanupEntries - Stack of cleanup entries.
llvm::SmallVector<CleanupEntry, 8> CleanupEntries;
typedef llvm::DenseMap<llvm::BasicBlock*, size_t> BlockScopeMap;
/// BlockScopes - Map of which "cleanup scope" scope basic blocks have.
BlockScopeMap BlockScopes;
/// CXXThisDecl - When generating code for a C++ member function,
/// this will hold the implicit 'this' declaration.
ImplicitParamDecl *CXXThisDecl;
/// CXXVTTDecl - When generating code for a base object constructor or
/// base object destructor with virtual bases, this will hold the implicit
/// VTT parameter.
ImplicitParamDecl *CXXVTTDecl;
/// CXXLiveTemporaryInfo - Holds information about a live C++ temporary.
struct CXXLiveTemporaryInfo {
/// Temporary - The live temporary.
const CXXTemporary *Temporary;
/// ThisPtr - The pointer to the temporary.
llvm::Value *ThisPtr;
/// DtorBlock - The destructor block.
llvm::BasicBlock *DtorBlock;
/// CondPtr - If this is a conditional temporary, this is the pointer to the
/// condition variable that states whether the destructor should be called
/// or not.
llvm::Value *CondPtr;
CXXLiveTemporaryInfo(const CXXTemporary *temporary,
llvm::Value *thisptr, llvm::BasicBlock *dtorblock,
llvm::Value *condptr)
: Temporary(temporary), ThisPtr(thisptr), DtorBlock(dtorblock),
CondPtr(condptr) { }
};
llvm::SmallVector<CXXLiveTemporaryInfo, 4> LiveTemporaries;
/// ConditionalBranchLevel - Contains the nesting level of the current
/// conditional branch. This is used so that we know if a temporary should be
/// destroyed conditionally.
unsigned ConditionalBranchLevel;
/// ByrefValueInfoMap - For each __block variable, contains a pair of the LLVM
/// type as well as the field number that contains the actual data.
llvm::DenseMap<const ValueDecl *, std::pair<const llvm::Type *,
unsigned> > ByRefValueInfo;
/// getByrefValueFieldNumber - Given a declaration, returns the LLVM field
/// number that holds the value.
unsigned getByRefValueLLVMField(const ValueDecl *VD) const;
public:
CodeGenFunction(CodeGenModule &cgm);
ASTContext &getContext() const;
CGDebugInfo *getDebugInfo() { return DebugInfo; }
llvm::BasicBlock *getInvokeDest() { return InvokeDest; }
void setInvokeDest(llvm::BasicBlock *B) { InvokeDest = B; }
llvm::LLVMContext &getLLVMContext() { return VMContext; }
//===--------------------------------------------------------------------===//
// 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);
/// GenerateObjCSetter - Synthesize an Objective-C property setter function
/// for the given property.
void GenerateObjCSetter(ObjCImplementationDecl *IMP,
const ObjCPropertyImplDecl *PID);
//===--------------------------------------------------------------------===//
// Block Bits
//===--------------------------------------------------------------------===//
llvm::Value *BuildBlockLiteralTmp(const BlockExpr *);
llvm::Constant *BuildDescriptorBlockDecl(bool BlockHasCopyDispose,
uint64_t Size,
const llvm::StructType *,
std::vector<HelperInfo> *);
llvm::Function *GenerateBlockFunction(const BlockExpr *BExpr,
const BlockInfo& Info,
const Decl *OuterFuncDecl,
llvm::DenseMap<const Decl*, llvm::Value*> ldm,
uint64_t &Size, uint64_t &Align,
llvm::SmallVector<const Expr *, 8> &subBlockDeclRefDecls,
bool &subBlockHasCopyDispose);
void BlockForwardSelf();
llvm::Value *LoadBlockStruct();
uint64_t AllocateBlockDecl(const BlockDeclRefExpr *E);
llvm::Value *GetAddrOfBlockDecl(const BlockDeclRefExpr *E);
const llvm::Type *BuildByRefType(const ValueDecl *D);
void GenerateCode(GlobalDecl GD, llvm::Function *Fn);
void StartFunction(GlobalDecl GD, QualType RetTy,
llvm::Function *Fn,
const FunctionArgList &Args,
SourceLocation StartLoc);
/// EmitReturnBlock - Emit the unified return block, trying to avoid its
/// emission when possible.
void 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());
/// DynamicTypeAdjust - Do the non-virtual and virtual adjustments on an
/// object pointer to alter the dynamic type of the pointer. Used by
/// GenerateCovariantThunk for building thunks.
llvm::Value *DynamicTypeAdjust(llvm::Value *V,
const ThunkAdjustment &Adjustment);
/// GenerateThunk - Generate a thunk for the given method
llvm::Constant *GenerateThunk(llvm::Function *Fn, const CXXMethodDecl *MD,
bool Extern,
const ThunkAdjustment &ThisAdjustment);
llvm::Constant *
GenerateCovariantThunk(llvm::Function *Fn, const CXXMethodDecl *MD,
bool Extern,
const CovariantThunkAdjustment &Adjustment);
void EmitCtorPrologue(const CXXConstructorDecl *CD, CXXCtorType Type);
void SynthesizeCXXCopyConstructor(const CXXConstructorDecl *Ctor,
CXXCtorType Type,
llvm::Function *Fn,
const FunctionArgList &Args);
void SynthesizeCXXCopyAssignment(const CXXMethodDecl *CD,
llvm::Function *Fn,
const FunctionArgList &Args);
void SynthesizeDefaultConstructor(const CXXConstructorDecl *Ctor,
CXXCtorType Type,
llvm::Function *Fn,
const FunctionArgList &Args);
void SynthesizeDefaultDestructor(const CXXDestructorDecl *Dtor,
CXXDtorType Type,
llvm::Function *Fn,
const FunctionArgList &Args);
/// EmitDtorEpilogue - Emit all code that comes at the end of class's
/// destructor. This is to call destructors on members and base classes in
/// reverse order of their construction.
void EmitDtorEpilogue(const CXXDestructorDecl *Dtor,
CXXDtorType Type);
/// 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, llvm::Value *ReturnValue);
const llvm::Type *ConvertTypeForMem(QualType T);
const llvm::Type *ConvertType(QualType 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();
/// hasAggregateLLVMType - Return true if the specified AST type will map into
/// an aggregate LLVM type or is void.
static bool hasAggregateLLVMType(QualType T);
/// createBasicBlock - Create an LLVM basic block.
llvm::BasicBlock *createBasicBlock(const char *Name="",
llvm::Function *Parent=0,
llvm::BasicBlock *InsertBefore=0) {
#ifdef NDEBUG
return llvm::BasicBlock::Create(VMContext, "", Parent, InsertBefore);
#else
return llvm::BasicBlock::Create(VMContext, Name, Parent, InsertBefore);
#endif
}
/// getBasicBlockForLabel - Return the LLVM basicblock that the specified
/// label maps to.
llvm::BasicBlock *getBasicBlockForLabel(const LabelStmt *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);
/// 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() != 0;
}
/// 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())
EmitBlock(createBasicBlock());
}
/// ErrorUnsupported - Print out an error that codegen doesn't support the
/// specified stmt yet.
void ErrorUnsupported(const Stmt *S, const char *Type,
bool OmitOnError=false);
//===--------------------------------------------------------------------===//
// Helpers
//===--------------------------------------------------------------------===//
Qualifiers MakeQualifiers(QualType T) {
Qualifiers Quals = getContext().getCanonicalType(T).getQualifiers();
Quals.setObjCGCAttr(getContext().getObjCGCAttrKind(T));
return Quals;
}
/// CreateTempAlloca - This creates a alloca and inserts it into the entry
/// block.
llvm::AllocaInst *CreateTempAlloca(const llvm::Type *Ty,
const llvm::Twine &Name = "tmp");
/// 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);
/// 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, llvm::Value *AggLoc = 0,
bool IsAggLocVolatile = false, bool IgnoreResult = false,
bool IsInitializer = 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.
llvm::Value *EmitVAListRef(const Expr *E);
/// EmitAnyExprToTemp - Similary to EmitAnyExpr(), however, the result will
/// always be accessible even if no aggregate location is provided.
RValue EmitAnyExprToTemp(const Expr *E, bool IsAggLocVolatile = false,
bool IsInitializer = false);
/// EmitAggregateCopy - Emit an aggrate copy.
///
/// \param isVolatile - True iff either the source or the destination is
/// volatile.
void EmitAggregateCopy(llvm::Value *DestPtr, llvm::Value *SrcPtr,
QualType EltTy, bool isVolatile=false);
void EmitAggregateClear(llvm::Value *DestPtr, QualType Ty);
/// StartBlock - Start new block named N. If insert block is a dummy block
/// then reuse it.
void StartBlock(const char *N);
/// GetAddrOfStaticLocalVar - Return the address of a static local variable.
llvm::Constant *GetAddrOfStaticLocalVar(const VarDecl *BVD);
/// GetAddrOfLocalVar - Return the address of a local variable.
llvm::Value *GetAddrOfLocalVar(const VarDecl *VD);
/// 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 LabelStmt *L);
llvm::BasicBlock *GetIndirectGotoBlock();
/// EmitMemSetToZero - Generate code to memset a value of the given type to 0.
void EmitMemSetToZero(llvm::Value *DestPtr, QualType Ty);
// EmitVAArg - Generate code to get an argument from the passed in pointer
// and update it accordingly. The return value is 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.
llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty);
/// EmitVLASize - Generate code for any VLA size expressions that might occur
/// in a variably modified type. If Ty is a VLA, will return the value that
/// corresponds to the size in bytes of the VLA type. Will return 0 otherwise.
///
/// This function can be called with a null (unreachable) insert point.
llvm::Value *EmitVLASize(QualType Ty);
// GetVLASize - Returns an LLVM value that corresponds to the size in bytes
// of a variable length array type.
llvm::Value *GetVLASize(const VariableArrayType *);
/// LoadCXXThis - Load the value of 'this'. This function is only valid while
/// generating code for an C++ member function.
llvm::Value *LoadCXXThis();
/// GetAddressOfBaseClass - This function will add the necessary delta to the
/// load of 'this' and returns address of the base class.
// FIXME. This currently only does a derived to non-virtual base conversion.
// Other kinds of conversions will come later.
llvm::Value *GetAddressOfBaseClass(llvm::Value *Value,
const CXXRecordDecl *ClassDecl,
const CXXRecordDecl *BaseClassDecl,
bool NullCheckValue);
llvm::Value *GetAddressOfDerivedClass(llvm::Value *Value,
const CXXRecordDecl *ClassDecl,
const CXXRecordDecl *DerivedClassDecl,
bool NullCheckValue);
llvm::Value *
GetVirtualCXXBaseClassOffset(llvm::Value *This,
const CXXRecordDecl *ClassDecl,
const CXXRecordDecl *BaseClassDecl);
void EmitClassAggrMemberwiseCopy(llvm::Value *DestValue,
llvm::Value *SrcValue,
const ArrayType *Array,
const CXXRecordDecl *BaseClassDecl,
QualType Ty);
void EmitClassAggrCopyAssignment(llvm::Value *DestValue,
llvm::Value *SrcValue,
const ArrayType *Array,
const CXXRecordDecl *BaseClassDecl,
QualType Ty);
void EmitClassMemberwiseCopy(llvm::Value *DestValue, llvm::Value *SrcValue,
const CXXRecordDecl *ClassDecl,
const CXXRecordDecl *BaseClassDecl,
QualType Ty);
void EmitClassCopyAssignment(llvm::Value *DestValue, llvm::Value *SrcValue,
const CXXRecordDecl *ClassDecl,
const CXXRecordDecl *BaseClassDecl,
QualType Ty);
void EmitCXXConstructorCall(const CXXConstructorDecl *D, CXXCtorType Type,
llvm::Value *This,
CallExpr::const_arg_iterator ArgBeg,
CallExpr::const_arg_iterator ArgEnd);
void EmitCXXAggrConstructorCall(const CXXConstructorDecl *D,
const ConstantArrayType *ArrayTy,
llvm::Value *ArrayPtr,
CallExpr::const_arg_iterator ArgBeg,
CallExpr::const_arg_iterator ArgEnd);
void EmitCXXAggrConstructorCall(const CXXConstructorDecl *D,
llvm::Value *NumElements,
llvm::Value *ArrayPtr,
CallExpr::const_arg_iterator ArgBeg,
CallExpr::const_arg_iterator ArgEnd);
void EmitCXXAggrDestructorCall(const CXXDestructorDecl *D,
const ArrayType *Array,
llvm::Value *This);
void EmitCXXAggrDestructorCall(const CXXDestructorDecl *D,
llvm::Value *NumElements,
llvm::Value *This);
llvm::Constant * GenerateCXXAggrDestructorHelper(const CXXDestructorDecl *D,
const ArrayType *Array,
llvm::Value *This);
void EmitCXXDestructorCall(const CXXDestructorDecl *D, CXXDtorType Type,
llvm::Value *This);
void PushCXXTemporary(const CXXTemporary *Temporary, llvm::Value *Ptr);
void PopCXXTemporary();
llvm::Value *EmitCXXNewExpr(const CXXNewExpr *E);
void EmitCXXDeleteExpr(const CXXDeleteExpr *E);
void EmitDeleteCall(const FunctionDecl *DeleteFD, llvm::Value *Ptr,
QualType DeleteTy);
llvm::Value* EmitCXXTypeidExpr(const CXXTypeidExpr *E);
llvm::Value *EmitDynamicCast(llvm::Value *V, const CXXDynamicCastExpr *DCE);
//===--------------------------------------------------------------------===//
// Declaration Emission
//===--------------------------------------------------------------------===//
/// EmitDecl - Emit a declaration.
///
/// This function can be called with a null (unreachable) insert point.
void EmitDecl(const Decl &D);
/// EmitBlockVarDecl - Emit a block variable declaration.
///
/// This function can be called with a null (unreachable) insert point.
void EmitBlockVarDecl(const VarDecl &D);
/// EmitLocalBlockVarDecl - Emit a local block variable declaration.
///
/// This function can be called with a null (unreachable) insert point.
void EmitLocalBlockVarDecl(const VarDecl &D);
void EmitStaticBlockVarDecl(const VarDecl &D);
/// EmitParmDecl - Emit a ParmVarDecl or an ImplicitParamDecl.
void EmitParmDecl(const VarDecl &D, llvm::Value *Arg);
//===--------------------------------------------------------------------===//
// 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);
/// 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);
RValue EmitCompoundStmt(const CompoundStmt &S, bool GetLast = false,
llvm::Value *AggLoc = 0, bool isAggVol = false);
/// EmitLabel - Emit the block for the given label. It is legal to call this
/// function even if there is no current insertion point.
void EmitLabel(const LabelStmt &S); // helper for EmitLabelStmt.
void EmitLabelStmt(const LabelStmt &S);
void EmitGotoStmt(const GotoStmt &S);
void EmitIndirectGotoStmt(const IndirectGotoStmt &S);
void EmitIfStmt(const IfStmt &S);
void EmitWhileStmt(const WhileStmt &S);
void EmitDoStmt(const DoStmt &S);
void EmitForStmt(const ForStmt &S);
void EmitReturnStmt(const ReturnStmt &S);
void EmitDeclStmt(const DeclStmt &S);
void EmitBreakStmt(const BreakStmt &S);
void EmitContinueStmt(const ContinueStmt &S);
void EmitSwitchStmt(const SwitchStmt &S);
void EmitDefaultStmt(const DefaultStmt &S);
void EmitCaseStmt(const CaseStmt &S);
void EmitCaseStmtRange(const CaseStmt &S);
void EmitAsmStmt(const AsmStmt &S);
void EmitObjCForCollectionStmt(const ObjCForCollectionStmt &S);
void EmitObjCAtTryStmt(const ObjCAtTryStmt &S);
void EmitObjCAtThrowStmt(const ObjCAtThrowStmt &S);
void EmitObjCAtSynchronizedStmt(const ObjCAtSynchronizedStmt &S);
void EmitCXXTryStmt(const CXXTryStmt &S);
//===--------------------------------------------------------------------===//
// LValue Expression Emission
//===--------------------------------------------------------------------===//
/// GetUndefRValue - Get an appropriate 'undef' rvalue for the given type.
RValue GetUndefRValue(QualType Ty);
/// EmitUnsupportedRValue - Emit a dummy r-value using the type of E
/// and issue an ErrorUnsupported style diagnostic (using the
/// provided Name).
RValue EmitUnsupportedRValue(const Expr *E,
const char *Name);
/// EmitUnsupportedLValue - Emit a dummy l-value using the type of E and issue
/// an ErrorUnsupported style diagnostic (using the provided Name).
LValue EmitUnsupportedLValue(const Expr *E,
const char *Name);
/// EmitLValue - Emit code to compute a designator that specifies the location
/// of the expression.
///
/// This can return one of two things: a simple address or a bitfield
/// reference. In either case, the LLVM Value* in the LValue structure is
/// guaranteed to be an LLVM pointer type.
///
/// If this returns a bitfield reference, nothing about the pointee type of
/// the LLVM value is known: For example, it may not be a pointer to an
/// integer.
///
/// If this returns a normal address, and if the lvalue's C type is fixed
/// size, this method guarantees that the returned pointer type will point to
/// an LLVM type of the same size of the lvalue's type. If the lvalue has a
/// variable length type, this is not possible.
///
LValue EmitLValue(const Expr *E);
/// EmitLoadOfScalar - Load a scalar value from an address, taking
/// care to appropriately convert from the memory representation to
/// the LLVM value representation.
llvm::Value *EmitLoadOfScalar(llvm::Value *Addr, bool Volatile,
QualType Ty);
/// EmitStoreOfScalar - Store a scalar value to an address, taking
/// care to appropriately convert from the memory representation to
/// the LLVM value representation.
void EmitStoreOfScalar(llvm::Value *Value, llvm::Value *Addr,
bool Volatile, QualType Ty);
/// EmitLoadOfLValue - Given an expression that represents a value lvalue,
/// this method emits the address of the lvalue, then loads the result as an
/// rvalue, returning the rvalue.
RValue EmitLoadOfLValue(LValue V, QualType LVType);
RValue EmitLoadOfExtVectorElementLValue(LValue V, QualType LVType);
RValue EmitLoadOfBitfieldLValue(LValue LV, QualType ExprType);
RValue EmitLoadOfPropertyRefLValue(LValue LV, QualType ExprType);
RValue EmitLoadOfKVCRefLValue(LValue LV, QualType ExprType);
/// EmitStoreThroughLValue - Store the specified rvalue into the specified
/// lvalue, where both are guaranteed to the have the same type, and that type
/// is 'Ty'.
void EmitStoreThroughLValue(RValue Src, LValue Dst, QualType Ty);
void EmitStoreThroughExtVectorComponentLValue(RValue Src, LValue Dst,
QualType Ty);
void EmitStoreThroughPropertyRefLValue(RValue Src, LValue Dst, QualType Ty);
void EmitStoreThroughKVCRefLValue(RValue Src, LValue Dst, QualType Ty);
/// EmitStoreThroughLValue - Store Src into Dst with same constraints as
/// EmitStoreThroughLValue.
///
/// \param Result [out] - If non-null, this will be set to a Value* for the
/// bit-field contents after the store, appropriate for use as the result of
/// an assignment to the bit-field.
void EmitStoreThroughBitfieldLValue(RValue Src, LValue Dst, QualType Ty,
llvm::Value **Result=0);
// Note: only availabe for agg return types
LValue EmitBinaryOperatorLValue(const BinaryOperator *E);
// Note: only available for agg return types
LValue EmitCallExprLValue(const CallExpr *E);
// Note: only available for agg return types
LValue EmitVAArgExprLValue(const VAArgExpr *E);
LValue EmitDeclRefLValue(const DeclRefExpr *E);
LValue EmitStringLiteralLValue(const StringLiteral *E);
LValue EmitObjCEncodeExprLValue(const ObjCEncodeExpr *E);
LValue EmitPredefinedFunctionName(unsigned Type);
LValue EmitPredefinedLValue(const PredefinedExpr *E);
LValue EmitUnaryOpLValue(const UnaryOperator *E);
LValue EmitArraySubscriptExpr(const ArraySubscriptExpr *E);
LValue EmitExtVectorElementExpr(const ExtVectorElementExpr *E);
LValue EmitMemberExpr(const MemberExpr *E);
LValue EmitCompoundLiteralLValue(const CompoundLiteralExpr *E);
LValue EmitConditionalOperatorLValue(const ConditionalOperator *E);
LValue EmitCastLValue(const CastExpr *E);
LValue EmitNullInitializationLValue(const CXXZeroInitValueExpr *E);
LValue EmitPointerToDataMemberLValue(const FieldDecl *Field);
llvm::Value *EmitIvarOffset(const ObjCInterfaceDecl *Interface,
const ObjCIvarDecl *Ivar);
LValue EmitLValueForField(llvm::Value* Base, const FieldDecl* Field,
bool isUnion, unsigned CVRQualifiers);
LValue EmitLValueForIvar(QualType ObjectTy,
llvm::Value* Base, const ObjCIvarDecl *Ivar,
unsigned CVRQualifiers);
LValue EmitLValueForBitfield(llvm::Value* Base, const FieldDecl* Field,
unsigned CVRQualifiers);
LValue EmitBlockDeclRefLValue(const BlockDeclRefExpr *E);
LValue EmitCXXConstructLValue(const CXXConstructExpr *E);
LValue EmitCXXBindTemporaryLValue(const CXXBindTemporaryExpr *E);
LValue EmitCXXExprWithTemporariesLValue(const CXXExprWithTemporaries *E);
LValue EmitCXXTypeidLValue(const CXXTypeidExpr *E);
LValue EmitObjCMessageExprLValue(const ObjCMessageExpr *E);
LValue EmitObjCIvarRefLValue(const ObjCIvarRefExpr *E);
LValue EmitObjCPropertyRefLValue(const ObjCPropertyRefExpr *E);
LValue EmitObjCKVCRefLValue(const ObjCImplicitSetterGetterRefExpr *E);
LValue EmitObjCSuperExprLValue(const ObjCSuperExpr *E);
LValue EmitStmtExprLValue(const StmtExpr *E);
LValue EmitPointerToDataMemberBinaryExpr(const BinaryOperator *E);
//===--------------------------------------------------------------------===//
// Scalar Expression Emission
//===--------------------------------------------------------------------===//
/// EmitCall - Generate a call of the given function, expecting the given
/// result type, and using the given argument list which specifies both the
/// LLVM arguments and the types they were derived from.
///
/// \param TargetDecl - If given, the decl of the function in a direct call;
/// used to set attributes on the call (noreturn, etc.).
RValue EmitCall(const CGFunctionInfo &FnInfo,
llvm::Value *Callee,
const CallArgList &Args,
const Decl *TargetDecl = 0);
RValue EmitCall(llvm::Value *Callee, QualType FnType,
CallExpr::const_arg_iterator ArgBeg,
CallExpr::const_arg_iterator ArgEnd,
const Decl *TargetDecl = 0);
RValue EmitCallExpr(const CallExpr *E);
llvm::Value *BuildVirtualCall(const CXXMethodDecl *MD, llvm::Value *This,
const llvm::Type *Ty);
llvm::Value *BuildVirtualCall(const CXXDestructorDecl *DD, CXXDtorType Type,
llvm::Value *&This, const llvm::Type *Ty);
RValue EmitCXXMemberCall(const CXXMethodDecl *MD,
llvm::Value *Callee,
llvm::Value *This,
CallExpr::const_arg_iterator ArgBeg,
CallExpr::const_arg_iterator ArgEnd);
RValue EmitCXXMemberCallExpr(const CXXMemberCallExpr *E);
RValue EmitCXXMemberPointerCallExpr(const CXXMemberCallExpr *E);
RValue EmitCXXOperatorMemberCallExpr(const CXXOperatorCallExpr *E,
const CXXMethodDecl *MD);
RValue EmitBuiltinExpr(const FunctionDecl *FD,
unsigned BuiltinID, const CallExpr *E);
RValue EmitBlockCallExpr(const CallExpr *E);
/// EmitTargetBuiltinExpr - Emit the given builtin call. Returns 0 if the call
/// is unhandled by the current target.
llvm::Value *EmitTargetBuiltinExpr(unsigned BuiltinID, const CallExpr *E);
llvm::Value *EmitX86BuiltinExpr(unsigned BuiltinID, const CallExpr *E);
llvm::Value *EmitPPCBuiltinExpr(unsigned BuiltinID, const CallExpr *E);
llvm::Value *EmitShuffleVector(llvm::Value* V1, llvm::Value *V2, ...);
llvm::Value *EmitVector(llvm::Value * const *Vals, unsigned NumVals,
bool isSplat = false);
llvm::Value *EmitObjCProtocolExpr(const ObjCProtocolExpr *E);
llvm::Value *EmitObjCStringLiteral(const ObjCStringLiteral *E);
llvm::Value *EmitObjCSelectorExpr(const ObjCSelectorExpr *E);
RValue EmitObjCMessageExpr(const ObjCMessageExpr *E);
RValue EmitObjCPropertyGet(const Expr *E);
RValue EmitObjCSuperPropertyGet(const Expr *Exp, const Selector &S);
void EmitObjCPropertySet(const Expr *E, RValue Src);
void EmitObjCSuperPropertySet(const Expr *E, const Selector &S, RValue Src);
/// EmitReferenceBindingToExpr - Emits a reference binding to the passed in
/// expression. Will emit a temporary variable if E is not an LValue.
RValue EmitReferenceBindingToExpr(const Expr* E, QualType DestType,
bool IsInitializer = false);
//===--------------------------------------------------------------------===//
// Expression Emission
//===--------------------------------------------------------------------===//
// Expressions are broken into three classes: scalar, complex, aggregate.
/// EmitScalarExpr - Emit the computation of the specified expression of LLVM
/// scalar type, returning the result.
llvm::Value *EmitScalarExpr(const Expr *E , bool IgnoreResultAssign = false);
/// EmitScalarConversion - Emit a conversion from the specified type to the
/// specified destination type, both of which are LLVM scalar types.
llvm::Value *EmitScalarConversion(llvm::Value *Src, QualType SrcTy,
QualType DstTy);
/// EmitComplexToScalarConversion - Emit a conversion from the specified
/// complex type to the specified destination type, where the destination type
/// is an LLVM scalar type.
llvm::Value *EmitComplexToScalarConversion(ComplexPairTy Src, QualType SrcTy,
QualType DstTy);
/// EmitAggExpr - Emit the computation of the specified expression of
/// aggregate type. The result is computed into DestPtr. Note that if
/// DestPtr is null, the value of the aggregate expression is not needed.
void EmitAggExpr(const Expr *E, llvm::Value *DestPtr, bool VolatileDest,
bool IgnoreResult = false, bool IsInitializer = false,
bool RequiresGCollection = false);
/// EmitGCMemmoveCollectable - Emit special API for structs with object
/// pointers.
void EmitGCMemmoveCollectable(llvm::Value *DestPtr, llvm::Value *SrcPtr,
QualType Ty);
/// EmitComplexExpr - Emit the computation of the specified expression of
/// complex type, returning the result.
ComplexPairTy EmitComplexExpr(const Expr *E, bool IgnoreReal = false,
bool IgnoreImag = false,
bool IgnoreRealAssign = false,
bool IgnoreImagAssign = false);
/// EmitComplexExprIntoAddr - Emit the computation of the specified expression
/// of complex type, storing into the specified Value*.
void EmitComplexExprIntoAddr(const Expr *E, llvm::Value *DestAddr,
bool DestIsVolatile);
/// StoreComplexToAddr - Store a complex number into the specified address.
void StoreComplexToAddr(ComplexPairTy V, llvm::Value *DestAddr,
bool DestIsVolatile);
/// LoadComplexFromAddr - Load a complex number from the specified address.
ComplexPairTy LoadComplexFromAddr(llvm::Value *SrcAddr, bool SrcIsVolatile);
/// CreateStaticBlockVarDecl - Create a zero-initialized LLVM global for a
/// static block var decl.
llvm::GlobalVariable * CreateStaticBlockVarDecl(const VarDecl &D,
const char *Separator,
llvm::GlobalValue::LinkageTypes Linkage);
/// EmitStaticCXXBlockVarDeclInit - Create the initializer for a C++ runtime
/// initialized static block var decl.
void EmitStaticCXXBlockVarDeclInit(const VarDecl &D,
llvm::GlobalVariable *GV);
/// EmitCXXGlobalVarDeclInit - Create the initializer for a C++
/// variable with global storage.
void EmitCXXGlobalVarDeclInit(const VarDecl &D, llvm::Constant *DeclPtr);
/// EmitCXXGlobalDtorRegistration - Emits a call to register the global ptr
/// with the C++ runtime so that its destructor will be called at exit.
void EmitCXXGlobalDtorRegistration(llvm::Constant *DtorFn,
llvm::Constant *DeclPtr);
/// GenerateCXXGlobalInitFunc - Generates code for initializing global
/// variables.
void GenerateCXXGlobalInitFunc(llvm::Function *Fn,
const VarDecl **Decls,
unsigned NumDecls);
void EmitCXXConstructExpr(llvm::Value *Dest, const CXXConstructExpr *E);
RValue EmitCXXExprWithTemporaries(const CXXExprWithTemporaries *E,
llvm::Value *AggLoc = 0,
bool IsAggLocVolatile = false,
bool IsInitializer = false);
void EmitCXXThrowExpr(const CXXThrowExpr *E);
//===--------------------------------------------------------------------===//
// Internal Helpers
//===--------------------------------------------------------------------===//
/// ContainsLabel - Return true if the statement contains a label in it. If
/// this statement is not executed normally, it not containing a label means
/// that we can just remove the code.
static bool ContainsLabel(const Stmt *S, bool IgnoreCaseStmts = false);
/// ConstantFoldsToSimpleInteger - If the specified expression does not fold
/// to a constant, or if it does but contains a label, return 0. If it
/// constant folds to 'true' and does not contain a label, return 1, if it
/// constant folds to 'false' and does not contain a label, return -1.
int ConstantFoldsToSimpleInteger(const Expr *Cond);
/// EmitBranchOnBoolExpr - Emit a branch on a boolean condition (e.g. for an
/// if statement) to the specified blocks. Based on the condition, this might
/// try to simplify the codegen of the conditional based on the branch.
void EmitBranchOnBoolExpr(const Expr *Cond, llvm::BasicBlock *TrueBlock,
llvm::BasicBlock *FalseBlock);
private:
void EmitReturnOfRValue(RValue RV, QualType Ty);
/// ExpandTypeFromArgs - Reconstruct a structure of type \arg Ty
/// from function arguments into \arg Dst. See ABIArgInfo::Expand.
///
/// \param AI - The first function argument of the expansion.
/// \return The argument following the last expanded function
/// argument.
llvm::Function::arg_iterator
ExpandTypeFromArgs(QualType Ty, LValue Dst,
llvm::Function::arg_iterator AI);
/// ExpandTypeToArgs - Expand an RValue \arg Src, with the LLVM type for \arg
/// Ty, into individual arguments on the provided vector \arg Args. See
/// ABIArgInfo::Expand.
void ExpandTypeToArgs(QualType Ty, RValue Src,
llvm::SmallVector<llvm::Value*, 16> &Args);
llvm::Value* EmitAsmInput(const AsmStmt &S,
const TargetInfo::ConstraintInfo &Info,
const Expr *InputExpr, std::string &ConstraintStr);
/// EmitCleanupBlock - emits a single cleanup block.
void EmitCleanupBlock();
/// AddBranchFixup - adds a branch instruction to the list of fixups for the
/// current cleanup scope.
void AddBranchFixup(llvm::BranchInst *BI);
/// EmitCallArg - Emit a single call argument.
RValue EmitCallArg(const Expr *E, QualType ArgType);
/// EmitCallArgs - Emit call arguments for a function.
/// The CallArgTypeInfo parameter is used for iterating over the known
/// argument types of the function being called.
template<typename T>
void EmitCallArgs(CallArgList& Args, const T* CallArgTypeInfo,
CallExpr::const_arg_iterator ArgBeg,
CallExpr::const_arg_iterator ArgEnd) {
CallExpr::const_arg_iterator Arg = ArgBeg;
// First, use the argument types that the type info knows about
if (CallArgTypeInfo) {
for (typename T::arg_type_iterator I = CallArgTypeInfo->arg_type_begin(),
E = CallArgTypeInfo->arg_type_end(); I != E; ++I, ++Arg) {
assert(Arg != ArgEnd && "Running over edge of argument list!");
QualType ArgType = *I;
assert(getContext().getCanonicalType(ArgType.getNonReferenceType()).
getTypePtr() ==
getContext().getCanonicalType(Arg->getType()).getTypePtr() &&
"type mismatch in call argument!");
Args.push_back(std::make_pair(EmitCallArg(*Arg, ArgType),
ArgType));
}
// Either we've emitted all the call args, or we have a call to a
// variadic function.
assert((Arg == ArgEnd || CallArgTypeInfo->isVariadic()) &&
"Extra arguments in non-variadic function!");
}
// If we still have any arguments, emit them using the type of the argument.
for (; Arg != ArgEnd; ++Arg) {
QualType ArgType = Arg->getType();
Args.push_back(std::make_pair(EmitCallArg(*Arg, ArgType),
ArgType));
}
}
};
} // end namespace CodeGen
} // end namespace clang
#endif