[LTO] Introduce an Output class to wrap the output stream creation (NFC)

Summary:
While NFC for now, this will allow more flexibility on the client side
to hold state necessary to back up the stream.
Also when adding caching, this class will grow in complexity.

Note I blindly modified the gold-plugin as I can't compile it.

Reviewers: tejohnson

Subscribers: mehdi_amini, llvm-commits

Differential Revision: https://reviews.llvm.org/D23542

llvm-svn: 278907

1 files changed, 11 insertions, 9 deletions

diff --git a/llvm/lib/LTO/LTOBackend.cpp b/llvm/lib/LTO/LTOBackend.cpp
index 8844199e7fc..e80aa7b349a 100644
--- a/llvm/lib/LTO/LTOBackend.cpp
+++ b/llvm/lib/LTO/LTOBackend.cpp
@@ -19,6 +19,7 @@
 #include "llvm/Analysis/TargetTransformInfo.h"
 #include "llvm/Bitcode/ReaderWriter.h"
 #include "llvm/IR/LegacyPassManager.h"
+#include "llvm/LTO/LTO.h"
 #include "llvm/MC/SubtargetFeature.h"
 #include "llvm/Support/Error.h"
 #include "llvm/Support/FileSystem.h"
@@ -144,12 +145,13 @@ bool opt(Config &C, TargetMachine *TM, unsigned Task, Module &M,
   return true;
 }
 
-void codegen(Config &C, TargetMachine *TM, AddStreamFn AddStream, unsigned Task,
+void codegen(Config &C, TargetMachine *TM, AddOutputFn AddOutput, unsigned Task,
              Module &M) {
   if (C.PreCodeGenModuleHook && !C.PreCodeGenModuleHook(Task, M))
     return;
 
-  std::unique_ptr<raw_pwrite_stream> OS = AddStream(Task);
+  auto Output = AddOutput(Task);
+  std::unique_ptr<raw_pwrite_stream> OS = Output->getStream();
   legacy::PassManager CodeGenPasses;
   if (TM->addPassesToEmitFile(CodeGenPasses, *OS,
                               TargetMachine::CGFT_ObjectFile))
@@ -157,7 +159,7 @@ void codegen(Config &C, TargetMachine *TM, AddStreamFn AddStream, unsigned Task,
   CodeGenPasses.run(M);
 }
 
-void splitCodeGen(Config &C, TargetMachine *TM, AddStreamFn AddStream,
+void splitCodeGen(Config &C, TargetMachine *TM, AddOutputFn AddOutput,
                   unsigned ParallelCodeGenParallelismLevel,
                   std::unique_ptr<Module> M) {
   ThreadPool CodegenThreadPool(ParallelCodeGenParallelismLevel);
@@ -190,7 +192,7 @@ void splitCodeGen(Config &C, TargetMachine *TM, AddStreamFn AddStream,
 
               std::unique_ptr<TargetMachine> TM =
                   createTargetMachine(C, MPartInCtx->getTargetTriple(), T);
-              codegen(C, TM.get(), AddStream, ThreadId, *MPartInCtx);
+              codegen(C, TM.get(), AddOutput, ThreadId, *MPartInCtx);
             },
             // Pass BC using std::move to ensure that it get moved rather than
             // copied into the thread's context.
@@ -214,7 +216,7 @@ Expected<const Target *> initAndLookupTarget(Config &C, Module &M) {
 
 }
 
-Error lto::backend(Config &C, AddStreamFn AddStream,
+Error lto::backend(Config &C, AddOutputFn AddOutput,
                    unsigned ParallelCodeGenParallelismLevel,
                    std::unique_ptr<Module> M) {
   Expected<const Target *> TOrErr = initAndLookupTarget(C, *M);
@@ -228,14 +230,14 @@ Error lto::backend(Config &C, AddStreamFn AddStream,
     return Error();
 
   if (ParallelCodeGenParallelismLevel == 1)
-    codegen(C, TM.get(), AddStream, 0, *M);
+    codegen(C, TM.get(), AddOutput, 0, *M);
   else
-    splitCodeGen(C, TM.get(), AddStream, ParallelCodeGenParallelismLevel,
+    splitCodeGen(C, TM.get(), AddOutput, ParallelCodeGenParallelismLevel,
                  std::move(M));
   return Error();
 }
 
-Error lto::thinBackend(Config &Conf, unsigned Task, AddStreamFn AddStream,
+Error lto::thinBackend(Config &Conf, unsigned Task, AddOutputFn AddOutput,
                        Module &Mod, ModuleSummaryIndex &CombinedIndex,
                        const FunctionImporter::ImportMapTy &ImportList,
                        const GVSummaryMapTy &DefinedGlobals,
@@ -281,6 +283,6 @@ Error lto::thinBackend(Config &Conf, unsigned Task, AddStreamFn AddStream,
   if (!opt(Conf, TM.get(), Task, Mod, /*IsThinLto=*/true))
     return Error();
 
-  codegen(Conf, TM.get(), AddStream, Task, Mod);
+  codegen(Conf, TM.get(), AddOutput, Task, Mod);
   return Error();
 }