[TimeProfiler] Fix "OptModule" section and add new "Backend" sections

Remove unnecessary "OptModule" section. Add "PerFunctionPasses",
"PerModulePasses" and "CodeGenPasses" sections under "Backend" section.

llvm-svn: 373142

Author: anton-afanasyev

clang/lib/CodeGen/BackendUtil.cpp

@@ -895,6 +895,7 @@ void EmitAssemblyHelper::EmitAssembly(BackendAction Action,
 
   {
     PrettyStackTraceString CrashInfo("Per-function optimization");
+    llvm::TimeTraceScope TimeScope("PerFunctionPasses", StringRef(""));
 
     PerFunctionPasses.doInitialization();
     for (Function &F : *TheModule)
@@ -905,11 +906,13 @@ void EmitAssemblyHelper::EmitAssembly(BackendAction Action,
 
   {
     PrettyStackTraceString CrashInfo("Per-module optimization passes");
+    llvm::TimeTraceScope TimeScope("PerModulePasses", StringRef(""));
     PerModulePasses.run(*TheModule);
   }
 
   {
     PrettyStackTraceString CrashInfo("Code generation");
+    llvm::TimeTraceScope TimeScope("CodeGenPasses", StringRef(""));
     CodeGenPasses.run(*TheModule);
   }
 

llvm/lib/IR/LegacyPassManager.cpp

@@ -1680,7 +1680,6 @@ bool FPPassManager::runOnFunction(Function &F) {
 bool FPPassManager::runOnModule(Module &M) {
   bool Changed = false;
 
-  llvm::TimeTraceScope TimeScope("OptModule", M.getName());
   for (Function &F : M)
     Changed |= runOnFunction(F);