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/Frontend/CodeGenOptions.h"
17#include "clang/AST/ASTContext.h"
18#include "clang/AST/DeclObjC.h"
19#include "clang/AST/Expr.h"
20#include "clang/Basic/Diagnostic.h"
21#include "clang/Basic/TargetInfo.h"
22#include "llvm/LLVMContext.h"
23#include "llvm/Module.h"
24#include "llvm/Target/TargetData.h"
25#include "llvm/ADT/OwningPtr.h"
26using namespace clang;
27
28namespace {
29  class CodeGeneratorImpl : public CodeGenerator {
30    DiagnosticsEngine &Diags;
31    llvm::OwningPtr<const llvm::TargetData> TD;
32    ASTContext *Ctx;
33    const CodeGenOptions CodeGenOpts;  // Intentionally copied in.
34  protected:
35    llvm::OwningPtr<llvm::Module> M;
36    llvm::OwningPtr<CodeGen::CodeGenModule> Builder;
37  public:
38    CodeGeneratorImpl(DiagnosticsEngine &diags, const std::string& ModuleName,
39                      const CodeGenOptions &CGO, llvm::LLVMContext& C)
40      : Diags(diags), CodeGenOpts(CGO), M(new llvm::Module(ModuleName, C)) {}
41
42    virtual ~CodeGeneratorImpl() {}
43
44    virtual llvm::Module* GetModule() {
45      return M.get();
46    }
47
48    virtual llvm::Module* ReleaseModule() {
49      return M.take();
50    }
51
52    virtual void Initialize(ASTContext &Context) {
53      Ctx = &Context;
54
55      M->setTargetTriple(Ctx->getTargetInfo().getTriple().getTriple());
56      M->setDataLayout(Ctx->getTargetInfo().getTargetDescription());
57      TD.reset(new llvm::TargetData(Ctx->getTargetInfo().getTargetDescription()));
58      Builder.reset(new CodeGen::CodeGenModule(Context, CodeGenOpts,
59                                               *M, *TD, Diags));
60    }
61
62    virtual void HandleTopLevelDecl(DeclGroupRef DG) {
63      // Make sure to emit all elements of a Decl.
64      for (DeclGroupRef::iterator I = DG.begin(), E = DG.end(); I != E; ++I)
65        Builder->EmitTopLevelDecl(*I);
66    }
67
68    /// HandleTagDeclDefinition - This callback is invoked each time a TagDecl
69    /// to (e.g. struct, union, enum, class) is completed. This allows the
70    /// client hack on the type, which can occur at any point in the file
71    /// (because these can be defined in declspecs).
72    virtual void HandleTagDeclDefinition(TagDecl *D) {
73      Builder->UpdateCompletedType(D);
74
75      // In C++, we may have member functions that need to be emitted at this
76      // point.
77      if (Ctx->getLangOptions().CPlusPlus && !D->isDependentContext()) {
78        for (DeclContext::decl_iterator M = D->decls_begin(),
79                                     MEnd = D->decls_end();
80             M != MEnd; ++M)
81          if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(*M))
82            if (Method->doesThisDeclarationHaveABody() &&
83                (Method->hasAttr<UsedAttr>() ||
84                 Method->hasAttr<ConstructorAttr>()))
85              Builder->EmitTopLevelDecl(Method);
86      }
87    }
88
89    virtual void HandleTranslationUnit(ASTContext &Ctx) {
90      if (Diags.hasErrorOccurred()) {
91        M.reset();
92        return;
93      }
94
95      if (Builder)
96        Builder->Release();
97    }
98
99    virtual void CompleteTentativeDefinition(VarDecl *D) {
100      if (Diags.hasErrorOccurred())
101        return;
102
103      Builder->EmitTentativeDefinition(D);
104    }
105
106    virtual void HandleVTable(CXXRecordDecl *RD, bool DefinitionRequired) {
107      if (Diags.hasErrorOccurred())
108        return;
109
110      Builder->EmitVTable(RD, DefinitionRequired);
111    }
112  };
113}
114
115CodeGenerator *clang::CreateLLVMCodeGen(DiagnosticsEngine &Diags,
116                                        const std::string& ModuleName,
117                                        const CodeGenOptions &CGO,
118                                        llvm::LLVMContext& C) {
119  return new CodeGeneratorImpl(Diags, ModuleName, CGO, C);
120}
121