ModuleBuilder.cpp revision 20ff3108fcd2c3bd734dc79efc22ebaa090abd41 
1//===--- ModuleBuilder.cpp - Emit LLVM Code from ASTs ---------------------===//
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// This builds an AST and converts it to LLVM Code.
11//
12//===----------------------------------------------------------------------===//
13
14#include "clang/CodeGen/ModuleBuilder.h"
15#include "CodeGenModule.h"
16#include "clang/AST/ASTConsumer.h"
17#include "clang/AST/ASTContext.h"
18#include "clang/AST/Decl.h"
19using namespace clang;
20
21//===----------------------------------------------------------------------===//
22// LLVM Emitter
23
24#include "clang/Basic/Diagnostic.h"
25#include "clang/Basic/TargetInfo.h"
26#include "clang/CodeGen/ModuleBuilder.h"
27#include "llvm/Module.h"
28#include "llvm/Target/TargetData.h"
29#include "llvm/Target/TargetMachine.h"
30
31namespace {
32  class CodeGenerator : public ASTConsumer {
33    Diagnostic &Diags;
34    const llvm::TargetData *TD;
35    ASTContext *Ctx;
36    const LangOptions &Features;
37    bool GenerateDebugInfo;
38  protected:
39    llvm::Module *&M;
40    CodeGen::CodeGenModule *Builder;
41  public:
42    CodeGenerator(Diagnostic &diags, const LangOptions &LO,
43                  llvm::Module *&DestModule, bool DebugInfoFlag)
44    : Diags(diags), Features(LO), GenerateDebugInfo(DebugInfoFlag),
45    M(DestModule) {}
46
47    ~CodeGenerator() {
48      delete Builder;
49      delete TD;
50    }
51
52    virtual void Initialize(ASTContext &Context) {
53      Ctx = &Context;
54
55      M->setTargetTriple(Ctx->Target.getTargetTriple());
56      M->setDataLayout(Ctx->Target.getTargetDescription());
57      TD = new llvm::TargetData(Ctx->Target.getTargetDescription());
58      Builder = new CodeGen::CodeGenModule(Context, Features, *M, *TD, Diags,
59                                           GenerateDebugInfo);
60    }
61
62    virtual void HandleTopLevelDecl(Decl *D) {
63      // If an error occurred, stop code generation, but continue parsing and
64      // semantic analysis (to ensure all warnings and errors are emitted).
65      if (Diags.hasErrorOccurred())
66        return;
67
68      if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
69        Builder->EmitFunction(FD);
70      } else if (isa<ObjCClassDecl>(D)){
71        //Forward declaration.  Only used for type checking.
72      } else if (ObjCProtocolDecl *PD = dyn_cast<ObjCProtocolDecl>(D)){
73        // Generate Protocol object.
74        Builder->EmitObjCProtocolImplementation(PD);
75      } else if (isa<ObjCCategoryDecl>(D)){
76        //Only used for typechecking.
77      } else if (ObjCCategoryImplDecl *OCD = dyn_cast<ObjCCategoryImplDecl>(D)){
78        // Generate methods, attach to category structure
79        Builder->EmitObjCCategoryImpl(OCD);
80      } else if (ObjCImplementationDecl * OID =
81          dyn_cast<ObjCImplementationDecl>(D)){
82        // Generate methods, attach to class structure
83        Builder->EmitObjCClassImplementation(OID);
84      } else if (isa<ObjCInterfaceDecl>(D)){
85        // Ignore - generated when the implementation decl is CodeGen'd
86      } else if (ObjCMethodDecl *OMD = dyn_cast<ObjCMethodDecl>(D)){
87        Builder->EmitObjCMethod(OMD);
88      } else if (VarDecl *VD = dyn_cast<VarDecl>(D)) {
89        if (VD->isFileVarDecl())
90          Builder->EmitGlobalVarDeclarator(VD);
91      } else if (isa<ObjCClassDecl>(D) || isa<ObjCCategoryDecl>(D)) {
92        // Forward declaration.  Only used for type checking.
93      } else if (ObjCMethodDecl *OMD = dyn_cast<ObjCMethodDecl>(D)){
94        Builder->EmitObjCMethod(OMD);
95      } else if (LinkageSpecDecl *LSD = dyn_cast<LinkageSpecDecl>(D)) {
96        if (LSD->getLanguage() == LinkageSpecDecl::lang_cxx)
97          Builder->WarnUnsupported(LSD, "linkage spec");
98        // FIXME: implement C++ linkage, C linkage works mostly by C
99        // language reuse already.
100      } else if (FileScopeAsmDecl *AD = dyn_cast<FileScopeAsmDecl>(D)) {
101        std::string AsmString(AD->getAsmString()->getStrData(),
102                              AD->getAsmString()->getByteLength());
103
104        const std::string &S = Builder->getModule().getModuleInlineAsm();
105        if (S.empty())
106          Builder->getModule().setModuleInlineAsm(AsmString);
107        else
108          Builder->getModule().setModuleInlineAsm(S + '\n' + AsmString);
109      } else {
110        assert(isa<TypeDecl>(D) && "Unknown top level decl");
111        // TODO: handle debug info?
112      }
113    }
114
115    /// HandleTagDeclDefinition - This callback is invoked each time a TagDecl
116    /// (e.g. struct, union, enum, class) is completed.  This allows the client to
117    /// hack on the type, which can occur at any point in the file (because these
118    /// can be defined in declspecs).
119    virtual void HandleTagDeclDefinition(TagDecl *D) {
120      Builder->UpdateCompletedType(D);
121    }
122
123  };
124}
125
126ASTConsumer *clang::CreateLLVMCodeGen(Diagnostic &Diags,
127                                      const LangOptions &Features,
128                                      llvm::Module *&DestModule,
129                                      bool GenerateDebugInfo) {
130  return new CodeGenerator(Diags, Features, DestModule, GenerateDebugInfo);
131}
132
133