llvm-capstone/clang/lib/CodeGen/ModuleBuilder.cpp
Alp Toker fb8d02b179 Implement -Wframe-larger-than backend diagnostic
Add driver and frontend support for the GCC -Wframe-larger-than=bytes warning.
This is the first GCC-compatible backend diagnostic built around LLVM's
reporting feature.

This commit adds infrastructure to perform reverse lookup from mangled names
emitted after LLVM IR generation. We use that to resolve precise locations and
originating AST functions, lambdas or block declarations to produce seamless
codegen-guided diagnostics.

An associated change, StringMap now maintains unique mangled name strings
instead of allocating copies. This is a net memory saving in C++ and a small
hit for C where we no longer reuse IdentifierInfo storage, pending further
optimisation.

llvm-svn: 210293
2014-06-05 22:10:59 +00:00

183 lines
5.8 KiB
C++

//===--- ModuleBuilder.cpp - Emit LLVM Code from ASTs ---------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This builds an AST and converts it to LLVM Code.
//
//===----------------------------------------------------------------------===//
#include "clang/CodeGen/ModuleBuilder.h"
#include "CGDebugInfo.h"
#include "CodeGenModule.h"
#include "clang/AST/ASTContext.h"
#include "clang/AST/DeclObjC.h"
#include "clang/AST/Expr.h"
#include "clang/Basic/Diagnostic.h"
#include "clang/Basic/TargetInfo.h"
#include "clang/Frontend/CodeGenOptions.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/Module.h"
#include <memory>
using namespace clang;
namespace {
class CodeGeneratorImpl : public CodeGenerator {
DiagnosticsEngine &Diags;
std::unique_ptr<const llvm::DataLayout> TD;
ASTContext *Ctx;
const CodeGenOptions CodeGenOpts; // Intentionally copied in.
protected:
std::unique_ptr<llvm::Module> M;
std::unique_ptr<CodeGen::CodeGenModule> Builder;
public:
CodeGeneratorImpl(DiagnosticsEngine &diags, const std::string& ModuleName,
const CodeGenOptions &CGO, llvm::LLVMContext& C)
: Diags(diags), CodeGenOpts(CGO),
M(new llvm::Module(ModuleName, C)) {}
virtual ~CodeGeneratorImpl() {}
llvm::Module* GetModule() override {
return M.get();
}
const Decl *GetDeclForMangledName(StringRef MangledName) override {
GlobalDecl Result;
if (!Builder->lookupRepresentativeDecl(MangledName, Result))
return nullptr;
const Decl *D = Result.getCanonicalDecl().getDecl();
if (auto FD = dyn_cast<FunctionDecl>(D)) {
if (FD->hasBody(FD))
return FD;
} else if (auto TD = dyn_cast<TagDecl>(D)) {
if (auto Def = TD->getDefinition())
return Def;
}
return D;
}
llvm::Module *ReleaseModule() override { return M.release(); }
void Initialize(ASTContext &Context) override {
Ctx = &Context;
M->setTargetTriple(Ctx->getTargetInfo().getTriple().getTriple());
M->setDataLayout(Ctx->getTargetInfo().getTargetDescription());
TD.reset(new llvm::DataLayout(Ctx->getTargetInfo().getTargetDescription()));
Builder.reset(new CodeGen::CodeGenModule(Context, CodeGenOpts, *M, *TD,
Diags));
for (size_t i = 0, e = CodeGenOpts.DependentLibraries.size(); i < e; ++i)
HandleDependentLibrary(CodeGenOpts.DependentLibraries[i]);
}
void HandleCXXStaticMemberVarInstantiation(VarDecl *VD) override {
if (Diags.hasErrorOccurred())
return;
Builder->HandleCXXStaticMemberVarInstantiation(VD);
}
bool HandleTopLevelDecl(DeclGroupRef DG) override {
if (Diags.hasErrorOccurred())
return true;
// Make sure to emit all elements of a Decl.
for (DeclGroupRef::iterator I = DG.begin(), E = DG.end(); I != E; ++I)
Builder->EmitTopLevelDecl(*I);
return true;
}
void HandleInlineMethodDefinition(CXXMethodDecl *D) override {
if (Diags.hasErrorOccurred())
return;
assert(D->doesThisDeclarationHaveABody());
// We may have member functions that need to be emitted at this point.
if (!D->isDependentContext() &&
(D->hasAttr<UsedAttr>() || D->hasAttr<ConstructorAttr>() ||
D->hasAttr<DLLExportAttr>())) {
Builder->EmitTopLevelDecl(D);
}
}
/// HandleTagDeclDefinition - This callback is invoked each time a TagDecl
/// to (e.g. struct, union, enum, class) is completed. This allows the
/// client hack on the type, which can occur at any point in the file
/// (because these can be defined in declspecs).
void HandleTagDeclDefinition(TagDecl *D) override {
if (Diags.hasErrorOccurred())
return;
Builder->UpdateCompletedType(D);
}
void HandleTagDeclRequiredDefinition(const TagDecl *D) override {
if (Diags.hasErrorOccurred())
return;
if (CodeGen::CGDebugInfo *DI = Builder->getModuleDebugInfo())
if (const RecordDecl *RD = dyn_cast<RecordDecl>(D))
DI->completeRequiredType(RD);
}
void HandleTranslationUnit(ASTContext &Ctx) override {
if (Diags.hasErrorOccurred()) {
if (Builder)
Builder->clear();
M.reset();
return;
}
if (Builder)
Builder->Release();
}
void CompleteTentativeDefinition(VarDecl *D) override {
if (Diags.hasErrorOccurred())
return;
Builder->EmitTentativeDefinition(D);
}
void HandleVTable(CXXRecordDecl *RD, bool DefinitionRequired) override {
if (Diags.hasErrorOccurred())
return;
Builder->EmitVTable(RD, DefinitionRequired);
}
void HandleLinkerOptionPragma(llvm::StringRef Opts) override {
Builder->AppendLinkerOptions(Opts);
}
void HandleDetectMismatch(llvm::StringRef Name,
llvm::StringRef Value) override {
Builder->AddDetectMismatch(Name, Value);
}
void HandleDependentLibrary(llvm::StringRef Lib) override {
Builder->AddDependentLib(Lib);
}
};
}
void CodeGenerator::anchor() { }
CodeGenerator *clang::CreateLLVMCodeGen(DiagnosticsEngine &Diags,
const std::string& ModuleName,
const CodeGenOptions &CGO,
const TargetOptions &/*TO*/,
llvm::LLVMContext& C) {
return new CodeGeneratorImpl(Diags, ModuleName, CGO, C);
}