Adds `-ftime-trace` option to clang that produces Chrome `chrome://tracing` compatible JSON profiling output dumps.

This change adds hierarchical "time trace" profiling blocks that can be visualized in Chrome, in a "flame chart" style. Each profiling block can have a "detail" string that for example indicates the file being processed, template name being instantiated, function being optimized etc.

This is taken from GitHub PR: https://github.com/aras-p/llvm-project-20170507/pull/2

Patch by Aras Pranckevičius.

Differential Revision: https://reviews.llvm.org/D58675

llvm-svn: 357340

1 files changed, 4 insertions, 0 deletions

diff --git a/clang/lib/Frontend/CompilerInstance.cpp b/clang/lib/Frontend/CompilerInstance.cpp
index 559bdb3..c5afe2a 100644
--- a/clang/lib/Frontend/CompilerInstance.cpp
+++ b/clang/lib/Frontend/CompilerInstance.cpp
@@ -46,6 +46,7 @@
 #include "llvm/Support/Path.h"
 #include "llvm/Support/Program.h"
 #include "llvm/Support/Signals.h"
+#include "llvm/Support/TimeProfiler.h"
 #include "llvm/Support/Timer.h"
 #include "llvm/Support/raw_ostream.h"
 #include <sys/stat.h>
@@ -1025,6 +1026,8 @@ compileModuleImpl(CompilerInstance &ImportingInstance, SourceLocation ImportLoc,
                       [](CompilerInstance &) {},
                   llvm::function_ref<void(CompilerInstance &)> PostBuildStep =
                       [](CompilerInstance &) {}) {
+  llvm::TimeTraceScope TimeScope("Module Compile", ModuleName);
+
   // Construct a compiler invocation for creating this module.
   auto Invocation =
       std::make_shared<CompilerInvocation>(ImportingInstance.getInvocation());
@@ -1701,6 +1704,7 @@ CompilerInstance::loadModule(SourceLocation ImportLoc,
       Timer.init("loading." + ModuleFileName, "Loading " + ModuleFileName,
                  *FrontendTimerGroup);
     llvm::TimeRegion TimeLoading(FrontendTimerGroup ? &Timer : nullptr);
+    llvm::TimeTraceScope TimeScope("Module Load", ModuleName);
 
     // Try to load the module file. If we are not trying to load from the
     // module cache, we don't know how to rebuild modules.