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//===--- Builtins.cpp - Builtin function implementation -------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements various things for builtin functions.
//
//===----------------------------------------------------------------------===//
#include "clang/AST/Builtins.h"
#include "clang/AST/ASTContext.h"
#include "clang/AST/Decl.h"
#include "clang/Basic/IdentifierTable.h"
#include "clang/Basic/TargetInfo.h"
using namespace clang;
static const Builtin::Info BuiltinInfo[] = {
{ "not a builtin function", 0, 0 },
#define BUILTIN(ID, TYPE, ATTRS) { #ID, TYPE, ATTRS },
#include "clang/AST/Builtins.def"
};
const Builtin::Info &Builtin::Context::GetRecord(unsigned ID) const {
if (ID < Builtin::FirstTSBuiltin)
return BuiltinInfo[ID];
assert(ID - Builtin::FirstTSBuiltin < NumTSRecords && "Invalid builtin ID!");
return TSRecords[ID - Builtin::FirstTSBuiltin];
}
/// InitializeBuiltins - Mark the identifiers for all the builtins with their
/// appropriate builtin ID # and mark any non-portable builtin identifiers as
/// such.
void Builtin::Context::InitializeBuiltins(IdentifierTable &Table,
const TargetInfo &Target) {
// Step #1: mark all target-independent builtins with their ID's.
for (unsigned i = Builtin::NotBuiltin+1; i != Builtin::FirstTSBuiltin; ++i)
Table.get(BuiltinInfo[i].Name).setBuiltinID(i);
// Step #2: Get target builtins.
Target.getTargetBuiltins(TSRecords, NumTSRecords);
// Step #3: Register target-specific builtins.
for (unsigned i = 0, e = NumTSRecords; i != e; ++i)
Table.get(TSRecords[i].Name).setBuiltinID(i+Builtin::FirstTSBuiltin);
}
/// DecodeTypeFromStr - This decodes one type descriptor from Str, advancing the
/// pointer over the consumed characters. This returns the resultant type.
static QualType DecodeTypeFromStr(const char *&Str, ASTContext &Context,
bool AllowTypeModifiers = true) {
// Modifiers.
bool Long = false, LongLong = false, Signed = false, Unsigned = false;
// Read the modifiers first.
bool Done = false;
while (!Done) {
switch (*Str++) {
default: Done = true; --Str; break;
case 'S':
assert(!Unsigned && "Can't use both 'S' and 'U' modifiers!");
assert(!Signed && "Can't use 'S' modifier multiple times!");
Signed = true;
break;
case 'U':
assert(!Signed && "Can't use both 'S' and 'U' modifiers!");
assert(!Unsigned && "Can't use 'S' modifier multiple times!");
Unsigned = true;
break;
case 'L':
assert(!LongLong && "Can't have LLL modifier");
if (Long)
LongLong = true;
else
Long = true;
break;
}
}
QualType Type;
// Read the base type.
switch (*Str++) {
default: assert(0 && "Unknown builtin type letter!");
case 'v':
assert(!Long && !Signed && !Unsigned && "Bad modifiers used with 'v'!");
Type = Context.VoidTy;
break;
case 'f':
assert(!Long && !Signed && !Unsigned && "Bad modifiers used with 'f'!");
Type = Context.FloatTy;
break;
case 'd':
assert(!LongLong && !Signed && !Unsigned && "Bad modifiers used with 'd'!");
if (Long)
Type = Context.LongDoubleTy;
else
Type = Context.DoubleTy;
break;
case 's':
assert(!LongLong && "Bad modifiers used with 's'!");
if (Unsigned)
Type = Context.UnsignedShortTy;
else
Type = Context.ShortTy;
break;
case 'i':
if (LongLong)
Type = Unsigned ? Context.UnsignedLongLongTy : Context.LongLongTy;
else if (Long)
Type = Unsigned ? Context.UnsignedLongTy : Context.LongTy;
else if (Unsigned)
Type = Context.UnsignedIntTy;
else
Type = Context.IntTy; // default is signed.
break;
case 'c':
assert(!Long && !LongLong && "Bad modifiers used with 'c'!");
if (Signed)
Type = Context.SignedCharTy;
else if (Unsigned)
Type = Context.UnsignedCharTy;
else
Type = Context.CharTy;
break;
case 'b': // boolean
assert(!Long && !Signed && !Unsigned && "Bad modifiers for 'b'!");
Type = Context.BoolTy;
break;
case 'z': // size_t.
assert(!Long && !Signed && !Unsigned && "Bad modifiers for 'z'!");
Type = Context.getSizeType();
break;
case 'F':
Type = Context.getCFConstantStringType();
break;
case 'a':
Type = Context.getBuiltinVaListType();
assert(!Type.isNull() && "builtin va list type not initialized!");
break;
case 'A':
// This is a "reference" to a va_list; however, what exactly
// this means depends on how va_list is defined. There are two
// different kinds of va_list: ones passed by value, and ones
// passed by reference. An example of a by-value va_list is
// x86, where va_list is a char*. An example of by-ref va_list
// is x86-64, where va_list is a __va_list_tag[1]. For x86,
// we want this argument to be a char*&; for x86-64, we want
// it to be a __va_list_tag*.
Type = Context.getBuiltinVaListType();
assert(!Type.isNull() && "builtin va list type not initialized!");
if (Type->isArrayType()) {
Type = Context.getArrayDecayedType(Type);
} else {
Type = Context.getReferenceType(Type);
}
break;
case 'V': {
char *End;
unsigned NumElements = strtoul(Str, &End, 10);
assert(End != Str && "Missing vector size");
Str = End;
QualType ElementType = DecodeTypeFromStr(Str, Context, false);
Type = Context.getVectorType(ElementType, NumElements);
break;
}
}
if (!AllowTypeModifiers)
return Type;
Done = false;
while (!Done) {
switch (*Str++) {
default: Done = true; --Str; break;
case '*':
Type = Context.getPointerType(Type);
break;
case '&':
Type = Context.getReferenceType(Type);
break;
case 'C':
Type = Type.getQualifiedType(QualType::Const);
break;
}
}
return Type;
}
/// GetBuiltinType - Return the type for the specified builtin.
QualType Builtin::Context::GetBuiltinType(unsigned id,
ASTContext &Context) const {
const char *TypeStr = GetRecord(id).Type;
llvm::SmallVector<QualType, 8> ArgTypes;
QualType ResType = DecodeTypeFromStr(TypeStr, Context);
while (TypeStr[0] && TypeStr[0] != '.') {
QualType Ty = DecodeTypeFromStr(TypeStr, Context);
// Do array -> pointer decay. The builtin should use the decayed type.
if (Ty->isArrayType())
Ty = Context.getArrayDecayedType(Ty);
ArgTypes.push_back(Ty);
}
assert((TypeStr[0] != '.' || TypeStr[1] == 0) &&
"'.' should only occur at end of builtin type list!");
// handle untyped/variadic arguments "T c99Style();" or "T cppStyle(...);".
if (ArgTypes.size() == 0 && TypeStr[0] == '.')
return Context.getFunctionTypeNoProto(ResType);
return Context.getFunctionType(ResType, &ArgTypes[0], ArgTypes.size(),
TypeStr[0] == '.', 0);
}