[LTO] Fix error reporting from lto_module_create_in_local_context()

Function lto_module_create_in_local_context() would previously
rely on the default LLVMContext being created for it by
LTOModule::makeLTOModule(). This context exits the program on
error and is not arranged to update sLastStringError in
tools/lto/lto.cpp.

Function lto_module_create_in_local_context() now creates an
LLVMContext by itself, sets it up correctly to its needs and then
passes it to LTOModule::createInLocalContext() which takes
ownership of the context and keeps it present for the lifetime of
the returned LTOModule.

Function LTOModule::makeLTOModule() is modified to take a
reference to LLVMContext (instead of a pointer) and no longer
creates a default context when nullptr is passed to it. Method
LTOModule::createInContext() that takes a pointer to LLVMContext
is removed because it allows to pass a nullptr to it. Instead
LTOModule::createFromBuffer() (that takes a reference to
LLVMContext) should be used.

Differential Revision: http://reviews.llvm.org/D17715

llvm-svn: 262330

1 files changed, 19 insertions, 34 deletions

diff --git a/llvm/lib/LTO/LTOModule.cpp b/llvm/lib/LTO/LTOModule.cpp
index 987da3e3210..9e49f0dc007 100644
--- a/llvm/lib/LTO/LTOModule.cpp
+++ b/llvm/lib/LTO/LTOModule.cpp
@@ -54,11 +54,6 @@ LTOModule::LTOModule(std::unique_ptr<object::IRObjectFile> Obj,
                      llvm::TargetMachine *TM)
     : IRFile(std::move(Obj)), _target(TM) {}
 
-LTOModule::LTOModule(std::unique_ptr<object::IRObjectFile> Obj,
-                     llvm::TargetMachine *TM,
-                     std::unique_ptr<LLVMContext> Context)
-    : OwnedContext(std::move(Context)), IRFile(std::move(Obj)), _target(TM) {}
-
 LTOModule::~LTOModule() {}
 
 /// isBitcodeFile - Returns 'true' if the file (or memory contents) is LLVM
@@ -110,7 +105,8 @@ LTOModule::createFromFile(LLVMContext &Context, const char *path,
     return EC;
   }
   std::unique_ptr<MemoryBuffer> Buffer = std::move(BufferOrErr.get());
-  return makeLTOModule(Buffer->getMemBufferRef(), options, &Context);
+  return makeLTOModule(Buffer->getMemBufferRef(), options, Context,
+                       /* ShouldBeLazy*/ false);
 }
 
 ErrorOr<std::unique_ptr<LTOModule>>
@@ -130,29 +126,32 @@ LTOModule::createFromOpenFileSlice(LLVMContext &Context, int fd,
     return EC;
   }
   std::unique_ptr<MemoryBuffer> Buffer = std::move(BufferOrErr.get());
-  return makeLTOModule(Buffer->getMemBufferRef(), options, &Context);
+  return makeLTOModule(Buffer->getMemBufferRef(), options, Context,
+                       /* ShouldBeLazy */ false);
 }
 
 ErrorOr<std::unique_ptr<LTOModule>>
 LTOModule::createFromBuffer(LLVMContext &Context, const void *mem,
                             size_t length, TargetOptions options,
                             StringRef path) {
-  return createInContext(mem, length, options, path, &Context);
+  StringRef Data((const char *)mem, length);
+  MemoryBufferRef Buffer(Data, path);
+  return makeLTOModule(Buffer, options, Context, /* ShouldBeLazy */ false);
 }
 
 ErrorOr<std::unique_ptr<LTOModule>>
-LTOModule::createInLocalContext(const void *mem, size_t length,
+LTOModule::createInLocalContext(std::unique_ptr<LLVMContext> Context,
+                                const void *mem, size_t length,
                                 TargetOptions options, StringRef path) {
-  return createInContext(mem, length, options, path, nullptr);
-}
-
-ErrorOr<std::unique_ptr<LTOModule>>
-LTOModule::createInContext(const void *mem, size_t length,
-                           TargetOptions options, StringRef path,
-                           LLVMContext *Context) {
   StringRef Data((const char *)mem, length);
   MemoryBufferRef Buffer(Data, path);
-  return makeLTOModule(Buffer, options, Context);
+  // If we own a context, we know this is being used only for symbol extraction,
+  // not linking.  Be lazy in that case.
+  ErrorOr<std::unique_ptr<LTOModule>> Ret =
+      makeLTOModule(Buffer, options, *Context, /* ShouldBeLazy */ true);
+  if (Ret)
+    (*Ret)->OwnedContext = std::move(Context);
+  return std::move(Ret);
 }
 
 static ErrorOr<std::unique_ptr<Module>>
@@ -187,18 +186,9 @@ parseBitcodeFileImpl(MemoryBufferRef Buffer, LLVMContext &Context,
 
 ErrorOr<std::unique_ptr<LTOModule>>
 LTOModule::makeLTOModule(MemoryBufferRef Buffer, TargetOptions options,
-                         LLVMContext *Context) {
-  std::unique_ptr<LLVMContext> OwnedContext;
-  if (!Context) {
-    OwnedContext = llvm::make_unique<LLVMContext>();
-    Context = OwnedContext.get();
-  }
-
-  // If we own a context, we know this is being used only for symbol
-  // extraction, not linking.  Be lazy in that case.
+                         LLVMContext &Context, bool ShouldBeLazy) {
   ErrorOr<std::unique_ptr<Module>> MOrErr =
-      parseBitcodeFileImpl(Buffer, *Context,
-                           /* ShouldBeLazy */ static_cast<bool>(OwnedContext));
+      parseBitcodeFileImpl(Buffer, Context, ShouldBeLazy);
   if (std::error_code EC = MOrErr.getError())
     return EC;
   std::unique_ptr<Module> &M = *MOrErr;
@@ -236,12 +226,7 @@ LTOModule::makeLTOModule(MemoryBufferRef Buffer, TargetOptions options,
   std::unique_ptr<object::IRObjectFile> IRObj(
       new object::IRObjectFile(Buffer, std::move(M)));
 
-  std::unique_ptr<LTOModule> Ret;
-  if (OwnedContext)
-    Ret.reset(new LTOModule(std::move(IRObj), target, std::move(OwnedContext)));
-  else
-    Ret.reset(new LTOModule(std::move(IRObj), target));
-
+  std::unique_ptr<LTOModule> Ret(new LTOModule(std::move(IRObj), target));
   Ret->parseSymbols();
   Ret->parseMetadata();