Add support for lazily linking bitcode files (using a new
-mlink-bitcode-file flag), and more generally llvm::Modules, before
running optimisations.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@143314 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CodeGenAction.cpp b/lib/CodeGen/CodeGenAction.cpp
index 11d6075..db2bab9 100644
--- a/lib/CodeGen/CodeGenAction.cpp
+++ b/lib/CodeGen/CodeGenAction.cpp
@@ -8,6 +8,7 @@
//===----------------------------------------------------------------------===//
#include "clang/CodeGen/CodeGenAction.h"
+#include "clang/Basic/FileManager.h"
#include "clang/Basic/SourceManager.h"
#include "clang/Basic/TargetInfo.h"
#include "clang/AST/ASTConsumer.h"
@@ -18,9 +19,11 @@
#include "clang/Frontend/CompilerInstance.h"
#include "clang/Frontend/FrontendDiagnostic.h"
#include "llvm/LLVMContext.h"
+#include "llvm/Linker.h"
#include "llvm/Module.h"
#include "llvm/Pass.h"
#include "llvm/ADT/OwningPtr.h"
+#include "llvm/Bitcode/ReaderWriter.h"
#include "llvm/Support/IRReader.h"
#include "llvm/Support/MemoryBuffer.h"
#include "llvm/Support/SourceMgr.h"
@@ -42,7 +45,7 @@
llvm::OwningPtr<CodeGenerator> Gen;
- llvm::OwningPtr<llvm::Module> TheModule;
+ llvm::OwningPtr<llvm::Module> TheModule, LinkModule;
public:
BackendConsumer(BackendAction action, DiagnosticsEngine &_Diags,
@@ -50,7 +53,9 @@
const TargetOptions &targetopts,
const LangOptions &langopts,
bool TimePasses,
- const std::string &infile, raw_ostream *OS,
+ const std::string &infile,
+ llvm::Module *LinkModule,
+ raw_ostream *OS,
LLVMContext &C) :
Diags(_Diags),
Action(action),
@@ -59,11 +64,13 @@
LangOpts(langopts),
AsmOutStream(OS),
LLVMIRGeneration("LLVM IR Generation Time"),
- Gen(CreateLLVMCodeGen(Diags, infile, compopts, C)) {
+ Gen(CreateLLVMCodeGen(Diags, infile, compopts, C)),
+ LinkModule(LinkModule) {
llvm::TimePassesIsEnabled = TimePasses;
}
llvm::Module *takeModule() { return TheModule.take(); }
+ llvm::Module *takeLinkModule() { return LinkModule.take(); }
virtual void Initialize(ASTContext &Ctx) {
Context = &Ctx;
@@ -122,6 +129,17 @@
assert(TheModule.get() == M &&
"Unexpected module change during IR generation");
+ // Link LinkModule into this module if present, preserving its validity.
+ if (LinkModule) {
+ std::string ErrorMsg;
+ if (Linker::LinkModules(M, LinkModule.get(), Linker::PreserveSource,
+ &ErrorMsg)) {
+ Diags.Report(diag::err_fe_cannot_link_module)
+ << LinkModule->getModuleIdentifier() << ErrorMsg;
+ return;
+ }
+ }
+
// Install an inline asm handler so that diagnostics get printed through
// our diagnostics hooks.
LLVMContext &Ctx = TheModule->getContext();
@@ -238,7 +256,8 @@
//
CodeGenAction::CodeGenAction(unsigned _Act, LLVMContext *_VMContext)
- : Act(_Act), VMContext(_VMContext ? _VMContext : new LLVMContext),
+ : Act(_Act), LinkModule(0),
+ VMContext(_VMContext ? _VMContext : new LLVMContext),
OwnsVMContext(!_VMContext) {}
CodeGenAction::~CodeGenAction() {
@@ -254,6 +273,10 @@
if (!getCompilerInstance().hasASTConsumer())
return;
+ // If we were given a link module, release consumer's ownership of it.
+ if (LinkModule)
+ BEConsumer->takeLinkModule();
+
// Steal the module from the consumer.
TheModule.reset(BEConsumer->takeModule());
}
@@ -294,12 +317,36 @@
if (BA != Backend_EmitNothing && !OS)
return 0;
+ llvm::Module *LinkModuleToUse = LinkModule;
+
+ // If we were not given a link module, and the user requested that one be
+ // loaded from bitcode, do so now.
+ const std::string &LinkBCFile = CI.getCodeGenOpts().LinkBitcodeFile;
+ if (!LinkModuleToUse && !LinkBCFile.empty()) {
+ std::string ErrorStr;
+
+ llvm::MemoryBuffer *BCBuf =
+ CI.getFileManager().getBufferForFile(LinkBCFile, &ErrorStr);
+ if (!BCBuf) {
+ CI.getDiagnostics().Report(diag::err_cannot_open_file)
+ << LinkBCFile << ErrorStr;
+ return 0;
+ }
+
+ LinkModuleToUse = getLazyBitcodeModule(BCBuf, *VMContext, &ErrorStr);
+ if (!LinkModuleToUse) {
+ CI.getDiagnostics().Report(diag::err_cannot_open_file)
+ << LinkBCFile << ErrorStr;
+ return 0;
+ }
+ }
+
BEConsumer =
new BackendConsumer(BA, CI.getDiagnostics(),
CI.getCodeGenOpts(), CI.getTargetOpts(),
CI.getLangOpts(),
- CI.getFrontendOpts().ShowTimers, InFile, OS.take(),
- *VMContext);
+ CI.getFrontendOpts().ShowTimers, InFile,
+ LinkModuleToUse, OS.take(), *VMContext);
return BEConsumer;
}