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//===----- CGCall.h - Encapsulate calling convention details ----*- C++ -*-===//
// The LLVM Compiler Infrastructure
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
// These classes wrap the information about a call or function
// definition used to handle ABI compliancy.
#include "CGValue.h"
#include "EHScopeStack.h"
#include "clang/AST/CanonicalType.h"
#include "clang/AST/Type.h"
#include "llvm/ADT/FoldingSet.h"
#include "llvm/IR/Value.h"
// FIXME: Restructure so we don't have to expose so much stuff.
#include "ABIInfo.h"
namespace llvm {
class AttributeSet;
class Function;
class Type;
class Value;
namespace clang {
class ASTContext;
class Decl;
class FunctionDecl;
class ObjCMethodDecl;
class VarDecl;
namespace CodeGen {
typedef SmallVector<llvm::AttributeSet, 8> AttributeListType;
struct CallArg {
RValue RV;
QualType Ty;
bool NeedsCopy;
CallArg(RValue rv, QualType ty, bool needscopy)
: RV(rv), Ty(ty), NeedsCopy(needscopy)
{ }
/// CallArgList - Type for representing both the value and type of
/// arguments in a call.
class CallArgList :
public SmallVector<CallArg, 16> {
CallArgList() : StackBase(0), StackBaseMem(0) {}
struct Writeback {
/// The original argument. Note that the argument l-value
/// is potentially null.
LValue Source;
/// The temporary alloca.
llvm::Value *Temporary;
/// A value to "use" after the writeback, or null.
llvm::Value *ToUse;
struct CallArgCleanup {
EHScopeStack::stable_iterator Cleanup;
/// The "is active" insertion point. This instruction is temporary and
/// will be removed after insertion.
llvm::Instruction *IsActiveIP;
void add(RValue rvalue, QualType type, bool needscopy = false) {
push_back(CallArg(rvalue, type, needscopy));
void addFrom(const CallArgList &other) {
insert(end(), other.begin(), other.end());
other.Writebacks.begin(), other.Writebacks.end());
void addWriteback(LValue srcLV, llvm::Value *temporary,
llvm::Value *toUse) {
Writeback writeback;
writeback.Source = srcLV;
writeback.Temporary = temporary;
writeback.ToUse = toUse;
bool hasWritebacks() const { return !Writebacks.empty(); }
typedef llvm::iterator_range<SmallVectorImpl<Writeback>::const_iterator>
writeback_const_range writebacks() const {
return writeback_const_range(Writebacks.begin(), Writebacks.end());
void addArgCleanupDeactivation(EHScopeStack::stable_iterator Cleanup,
llvm::Instruction *IsActiveIP) {
CallArgCleanup ArgCleanup;
ArgCleanup.Cleanup = Cleanup;
ArgCleanup.IsActiveIP = IsActiveIP;
ArrayRef<CallArgCleanup> getCleanupsToDeactivate() const {
return CleanupsToDeactivate;
void allocateArgumentMemory(CodeGenFunction &CGF);
llvm::Instruction *getStackBase() const { return StackBase; }
void freeArgumentMemory(CodeGenFunction &CGF) const;
/// \brief Returns if we're using an inalloca struct to pass arguments in
/// memory.
bool isUsingInAlloca() const { return StackBase; }
SmallVector<Writeback, 1> Writebacks;
/// Deactivate these cleanups immediately before making the call. This
/// is used to cleanup objects that are owned by the callee once the call
/// occurs.
SmallVector<CallArgCleanup, 1> CleanupsToDeactivate;
/// The stacksave call. It dominates all of the argument evaluation.
llvm::CallInst *StackBase;
/// The alloca holding the stackbase. We need it to maintain SSA form.
llvm::AllocaInst *StackBaseMem;
/// The iterator pointing to the stack restore cleanup. We manually run and
/// deactivate this cleanup after the call in the unexceptional case because
/// it doesn't run in the normal order.
EHScopeStack::stable_iterator StackCleanup;
/// FunctionArgList - Type for representing both the decl and type
/// of parameters to a function. The decl must be either a
/// ParmVarDecl or ImplicitParamDecl.
class FunctionArgList : public SmallVector<const VarDecl*, 16> {
/// ReturnValueSlot - Contains the address where the return value of a
/// function can be stored, and whether the address is volatile or not.
class ReturnValueSlot {
llvm::PointerIntPair<llvm::Value *, 1, bool> Value;
ReturnValueSlot() {}
ReturnValueSlot(llvm::Value *Value, bool IsVolatile)
: Value(Value, IsVolatile) {}
bool isNull() const { return !getValue(); }
bool isVolatile() const { return Value.getInt(); }
llvm::Value *getValue() const { return Value.getPointer(); }
} // end namespace CodeGen
} // end namespace clang