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
diff --git a/clang/lib/Parse/ParseAST.cpp b/clang/lib/Parse/ParseAST.cpp
index 5ecfc7d..3efd893 100644
--- a/clang/lib/Parse/ParseAST.cpp
+++ b/clang/lib/Parse/ParseAST.cpp
@@ -22,6 +22,7 @@
#include "clang/Sema/SemaConsumer.h"
#include "clang/Sema/TemplateInstCallback.h"
#include "llvm/Support/CrashRecoveryContext.h"
+#include "llvm/Support/TimeProfiler.h"
#include <cstdio>
#include <memory>
@@ -150,6 +151,7 @@
bool HaveLexer = S.getPreprocessor().getCurrentLexer();
if (HaveLexer) {
+ llvm::TimeTraceScope TimeScope("Frontend", StringRef(""));
P.Initialize();
Parser::DeclGroupPtrTy ADecl;
for (bool AtEOF = P.ParseFirstTopLevelDecl(ADecl); !AtEOF;