blob: 63b9d6f881c84c572c8e0a868ec9ceeb657e4b80 [file] [log] [blame]
//===--- CGDecl.cpp - Emit LLVM Code for declarations ---------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by Chris Lattner and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This contains code to emit Decl nodes as LLVM code.
//
//===----------------------------------------------------------------------===//
#include "CodeGenFunction.h"
#include "clang/AST/AST.h"
#include "llvm/Type.h"
using namespace clang;
using namespace CodeGen;
void CodeGenFunction::EmitDecl(const Decl &D) {
switch (D.getKind()) {
default: assert(0 && "Unknown decl kind!");
case Decl::FileVariable:
assert(0 && "Should not see file-scope variables inside a function!");
case Decl::ParmVariable:
assert(0 && "Parmdecls should not be in declstmts!");
case Decl::Typedef: // typedef int X;
case Decl::Function: // void X();
case Decl::Struct: // struct X;
case Decl::Union: // union X;
case Decl::Class: // class X;
case Decl::Enum: // enum X;
// None of these decls require codegen support.
return;
case Decl::BlockVariable:
return EmitBlockVarDecl(cast<BlockVarDecl>(D));
case Decl::EnumConstant:
return EmitEnumConstantDecl(cast<EnumConstantDecl>(D));
}
}
void CodeGenFunction::EmitEnumConstantDecl(const EnumConstantDecl &D) {
assert(0 && "FIXME: Enum constant decls not implemented yet!");
}
/// EmitBlockVarDecl - This method handles emission of any variable declaration
/// inside a function, including static vars etc.
void CodeGenFunction::EmitBlockVarDecl(const BlockVarDecl &D) {
switch (D.getStorageClass()) {
case VarDecl::Static:
assert(0 && "FIXME: local static vars not implemented yet");
case VarDecl::Extern:
assert(0 && "FIXME: should call up to codegenmodule");
default:
assert((D.getStorageClass() == VarDecl::None ||
D.getStorageClass() == VarDecl::Auto ||
D.getStorageClass() == VarDecl::Register) &&
"Unknown storage class");
return EmitLocalBlockVarDecl(D);
}
}
/// EmitLocalBlockVarDecl - Emit code and set up an entry in LocalDeclMap for a
/// variable declaration with auto, register, or no storage class specifier.
/// These turn into simple stack objects.
void CodeGenFunction::EmitLocalBlockVarDecl(const BlockVarDecl &D) {
QualType Ty = D.getCanonicalType();
llvm::Value *DeclPtr;
if (Ty->isConstantSizeType(getContext())) {
// A normal fixed sized variable becomes an alloca in the entry block.
const llvm::Type *LTy = ConvertType(Ty);
// TODO: Alignment
DeclPtr = CreateTempAlloca(LTy, D.getName());
} else {
// TODO: Create a dynamic alloca.
assert(0 && "FIXME: Local VLAs not implemented yet");
}
llvm::Value *&DMEntry = LocalDeclMap[&D];
assert(DMEntry == 0 && "Decl already exists in localdeclmap!");
DMEntry = DeclPtr;
// If this local has an initializer, emit it now.
if (const Expr *Init = D.getInit())
EmitStoreThroughLValue(EmitExpr(Init), LValue::MakeAddr(DeclPtr), Ty);
}
/// Emit an alloca for the specified parameter and set up LocalDeclMap.
void CodeGenFunction::EmitParmDecl(const ParmVarDecl &D, llvm::Value *Arg) {
QualType Ty = D.getCanonicalType();
llvm::Value *DeclPtr;
if (!Ty->isConstantSizeType(getContext())) {
// Variable sized values always are passed by-reference.
DeclPtr = Arg;
} else {
// A fixed sized first class variable becomes an alloca in the entry block.
const llvm::Type *LTy = ConvertType(Ty);
if (LTy->isFirstClassType()) {
// TODO: Alignment
DeclPtr = new llvm::AllocaInst(LTy, 0, std::string(D.getName())+".addr",
AllocaInsertPt);
// Store the initial value into the alloca.
Builder.CreateStore(Arg, DeclPtr);
} else {
// Otherwise, if this is an aggregate, just use the input pointer.
DeclPtr = Arg;
}
Arg->setName(D.getName());
}
llvm::Value *&DMEntry = LocalDeclMap[&D];
assert(DMEntry == 0 && "Decl already exists in localdeclmap!");
DMEntry = DeclPtr;
}