Revert "Add two time-trace scope variables."

This reverts commit 33b8586.

This causes a large compile-time regression (about 1% for unoptimized
builds).

Author: nikic

clang/docs/ReleaseNotes.rst

@@ -427,14 +427,6 @@ Improvements to Clang's diagnostics
   (or, more commonly, ``NULL`` when the platform defines it as ``__null``) to be more consistent
   with GCC.
 
-Improvements to Clang's time-trace
-----------------------------------
-- Two time-trace scope variables are added. A time trace scope variable of
-  ``ParseDeclarationOrFunctionDefinition`` with the function's source location
-  is added to record the time spent parsing the function's declaration or
-  definition. Another time trace scope variable of ``ParseFunctionDefinition``
-  is also added to record the name of the defined function.
-
 Bug Fixes in This Version
 -------------------------
 - Fixed an issue where a class template specialization whose declaration is

clang/lib/Parse/Parser.cpp

@@ -13,16 +13,15 @@
 #include "clang/Parse/Parser.h"
 #include "clang/AST/ASTConsumer.h"
 #include "clang/AST/ASTContext.h"
-#include "clang/AST/ASTLambda.h"
 #include "clang/AST/DeclTemplate.h"
+#include "clang/AST/ASTLambda.h"
 #include "clang/Basic/FileManager.h"
 #include "clang/Parse/ParseDiagnostic.h"
 #include "clang/Parse/RAIIObjectsForParser.h"
 #include "clang/Sema/DeclSpec.h"
 #include "clang/Sema/ParsedTemplate.h"
 #include "clang/Sema/Scope.h"
 #include "llvm/Support/Path.h"
-#include "llvm/Support/TimeProfiler.h"
 using namespace clang;
 
 
@@ -1230,13 +1229,6 @@ Parser::DeclGroupPtrTy Parser::ParseDeclOrFunctionDefInternal(
 Parser::DeclGroupPtrTy Parser::ParseDeclarationOrFunctionDefinition(
     ParsedAttributes &Attrs, ParsedAttributes &DeclSpecAttrs,
     ParsingDeclSpec *DS, AccessSpecifier AS) {
-  // Add an enclosing time trace scope for a bunch of small scopes with
-  // "EvaluateAsConstExpr".
-  llvm::TimeTraceScope TimeScope(
-      "ParseDeclarationOrFunctionDefinition",
-      Tok.getLocation().printToString(
-          Actions.getASTContext().getSourceManager()));
-
   if (DS) {
     return ParseDeclOrFunctionDefInternal(Attrs, DeclSpecAttrs, *DS, AS);
   } else {
@@ -1267,10 +1259,6 @@ Parser::DeclGroupPtrTy Parser::ParseDeclarationOrFunctionDefinition(
 Decl *Parser::ParseFunctionDefinition(ParsingDeclarator &D,
                                       const ParsedTemplateInfo &TemplateInfo,
                                       LateParsedAttrList *LateParsedAttrs) {
-  llvm::TimeTraceScope TimeScope(
-      "ParseFunctionDefinition",
-      Actions.GetNameForDeclarator(D).getName().getAsString());
-
   // Poison SEH identifiers so they are flagged as illegal in function bodies.
   PoisonSEHIdentifiersRAIIObject PoisonSEHIdentifiers(*this, true);
   const DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo();

clang/test/Driver/check-time-trace-ParseDeclarationOrFunctionDefinition.cpp

@@ -177,29 +177,22 @@ constexpr int slow_init_list[] = {1, 1, 2, 3, 5, 8, 13, 21}; // 25th line
   std::string TraceGraph = buildTraceGraph(Json);
   ASSERT_TRUE(TraceGraph == R"(
 Frontend
-| ParseDeclarationOrFunctionDefinition (test.cc:2:1)
-| ParseDeclarationOrFunctionDefinition (test.cc:6:1)
-| | ParseFunctionDefinition (slow_func)
-| | | EvaluateAsRValue (<test.cc:8:21>)
-| | | EvaluateForOverflow (<test.cc:8:21, col:25>)
-| | | EvaluateForOverflow (<test.cc:8:30, col:32>)
-| | | EvaluateAsRValue (<test.cc:9:14>)
-| | | EvaluateForOverflow (<test.cc:9:9, col:14>)
-| | | isPotentialConstantExpr (slow_namespace::slow_func)
-| | | EvaluateAsBooleanCondition (<test.cc:8:21, col:25>)
-| | | | EvaluateAsRValue (<test.cc:8:21, col:25>)
-| | | EvaluateAsBooleanCondition (<test.cc:8:21, col:25>)
-| | | | EvaluateAsRValue (<test.cc:8:21, col:25>)
-| ParseDeclarationOrFunctionDefinition (test.cc:16:1)
-| | ParseFunctionDefinition (slow_test)
-| | | EvaluateAsInitializer (slow_value)
-| | | EvaluateAsConstantExpr (<test.cc:17:33, col:59>)
-| | | EvaluateAsConstantExpr (<test.cc:18:11, col:37>)
-| ParseDeclarationOrFunctionDefinition (test.cc:22:1)
-| | EvaluateAsConstantExpr (<test.cc:23:31, col:57>)
-| | EvaluateAsRValue (<test.cc:22:14, line:23:58>)
-| ParseDeclarationOrFunctionDefinition (test.cc:25:1)
-| | EvaluateAsInitializer (slow_init_list)
+| EvaluateAsRValue (<test.cc:8:21>)
+| EvaluateForOverflow (<test.cc:8:21, col:25>)
+| EvaluateForOverflow (<test.cc:8:30, col:32>)
+| EvaluateAsRValue (<test.cc:9:14>)
+| EvaluateForOverflow (<test.cc:9:9, col:14>)
+| isPotentialConstantExpr (slow_namespace::slow_func)
+| EvaluateAsBooleanCondition (<test.cc:8:21, col:25>)
+| | EvaluateAsRValue (<test.cc:8:21, col:25>)
+| EvaluateAsBooleanCondition (<test.cc:8:21, col:25>)
+| | EvaluateAsRValue (<test.cc:8:21, col:25>)
+| EvaluateAsInitializer (slow_value)
+| EvaluateAsConstantExpr (<test.cc:17:33, col:59>)
+| EvaluateAsConstantExpr (<test.cc:18:11, col:37>)
+| EvaluateAsConstantExpr (<test.cc:23:31, col:57>)
+| EvaluateAsRValue (<test.cc:22:14, line:23:58>)
+| EvaluateAsInitializer (slow_init_list)
 | PerformPendingInstantiations
 )");
 
@@ -220,9 +213,8 @@ struct {
   std::string TraceGraph = buildTraceGraph(Json);
   ASSERT_TRUE(TraceGraph == R"(
 Frontend
-| ParseDeclarationOrFunctionDefinition (test.c:2:1)
-| | isIntegerConstantExpr (<test.c:3:18>)
-| | EvaluateKnownConstIntCheckOverflow (<test.c:3:18>)
+| isIntegerConstantExpr (<test.c:3:18>)
+| EvaluateKnownConstIntCheckOverflow (<test.c:3:18>)
 | PerformPendingInstantiations
 )");