CGCall.cpp revision 46f45b9bec4a265ad8400a538e5ec3a5683617f1 
1//===----- CGCall.h - Encapsulate calling convention details ----*- C++ -*-===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// These classes wrap the information about a call or function
11// definition used to handle ABI compliancy.
12//
13//===----------------------------------------------------------------------===//
14
15#include "CGCall.h"
16#include "CodeGenFunction.h"
17#include "clang/AST/ASTContext.h"
18#include "clang/AST/Decl.h"
19#include "clang/AST/DeclObjC.h"
20#include "llvm/ParameterAttributes.h"
21using namespace clang;
22using namespace CodeGen;
23
24/***/
25
26static void
27constructParamAttrListInternal(const Decl *TargetDecl,
28                               const llvm::SmallVector<QualType, 16> &ArgTypes,
29                               ParamAttrListType &PAL) {
30  unsigned FuncAttrs = 0;
31
32  if (TargetDecl) {
33    if (TargetDecl->getAttr<NoThrowAttr>())
34      FuncAttrs |= llvm::ParamAttr::NoUnwind;
35    if (TargetDecl->getAttr<NoReturnAttr>())
36      FuncAttrs |= llvm::ParamAttr::NoReturn;
37  }
38
39  unsigned Index = 1;
40  if (CodeGenFunction::hasAggregateLLVMType(ArgTypes[0])) {
41    PAL.push_back(llvm::ParamAttrsWithIndex::get(Index,
42                                                 llvm::ParamAttr::StructRet));
43    ++Index;
44  } else if (ArgTypes[0]->isPromotableIntegerType()) {
45    if (ArgTypes[0]->isSignedIntegerType()) {
46      FuncAttrs |= llvm::ParamAttr::SExt;
47    } else if (ArgTypes[0]->isUnsignedIntegerType()) {
48      FuncAttrs |= llvm::ParamAttr::ZExt;
49    }
50  }
51  if (FuncAttrs)
52    PAL.push_back(llvm::ParamAttrsWithIndex::get(0, FuncAttrs));
53  for (llvm::SmallVector<QualType, 8>::const_iterator i = ArgTypes.begin() + 1,
54         e = ArgTypes.end(); i != e; ++i, ++Index) {
55    QualType ParamType = *i;
56    unsigned ParamAttrs = 0;
57    if (ParamType->isRecordType())
58      ParamAttrs |= llvm::ParamAttr::ByVal;
59    if (ParamType->isPromotableIntegerType()) {
60      if (ParamType->isSignedIntegerType()) {
61        ParamAttrs |= llvm::ParamAttr::SExt;
62      } else if (ParamType->isUnsignedIntegerType()) {
63        ParamAttrs |= llvm::ParamAttr::ZExt;
64      }
65    }
66    if (ParamAttrs)
67      PAL.push_back(llvm::ParamAttrsWithIndex::get(Index, ParamAttrs));
68  }
69}
70
71/***/
72
73// FIXME: Use iterator and sidestep silly type array creation.
74
75CGFunctionInfo::CGFunctionInfo(const FunctionDecl *FD)
76  : TheDecl(FD)
77{
78  const FunctionType *FTy = FD->getType()->getAsFunctionType();
79  const FunctionTypeProto *FTP = dyn_cast<FunctionTypeProto>(FTy);
80
81  ArgTypes.push_back(FTy->getResultType());
82  if (FTP)
83    for (unsigned i = 0, e = FTP->getNumArgs(); i != e; ++i)
84      ArgTypes.push_back(FTP->getArgType(i));
85}
86
87CGFunctionInfo::CGFunctionInfo(const ObjCMethodDecl *MD,
88                               const ASTContext &Context)
89  : TheDecl(MD)
90{
91  ArgTypes.push_back(MD->getResultType());
92  ArgTypes.push_back(MD->getSelfDecl()->getType());
93  ArgTypes.push_back(Context.getObjCSelType());
94  for (ObjCMethodDecl::param_const_iterator i = MD->param_begin(),
95         e = MD->param_end(); i != e; ++i)
96    ArgTypes.push_back((*i)->getType());
97}
98
99void CGFunctionInfo::constructParamAttrList(ParamAttrListType &PAL) const {
100  constructParamAttrListInternal(TheDecl, ArgTypes, PAL);
101}
102
103/***/
104
105CGCallInfo::CGCallInfo(QualType _ResultType, const CallArgList &_Args)
106  : ResultType(_ResultType),
107    Args(_Args) {
108  ArgTypes.push_back(ResultType);
109  for (CallArgList::const_iterator i = Args.begin(), e = Args.end(); i!=e; ++i)
110    ArgTypes.push_back(i->second);
111}
112
113void CGCallInfo::constructParamAttrList(ParamAttrListType &PAL) const {
114  // FIXME: Provide TargetDecl so nounwind, noreturn, etc, etc get set.
115  constructParamAttrListInternal(0, ArgTypes, PAL);
116}
117