From 3a6fcd9a38b60c88d1ded2ae778c9e973b9561f3 Mon Sep 17 00:00:00 2001 From: Serge Pavlov Date: Sun, 6 Dec 2015 14:32:39 +0000 Subject: [PATCH] [PGO] Instrument only base constructors and destructors. Constructors and destructors may be represented by several functions in IR. Only base structors correspond to source code, others are small pieces of code and eventually call the base variant. In this case instrumentation of non-base structors has little sense, this fix remove it. Now profile data of a declaration corresponds to exactly one function in IR, it agrees with the current logic of the profile data loading. This change fixes PR24996. Differential Revision: http://reviews.llvm.org/D15158 git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@254876 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/CodeGen/CGBlocks.cpp | 2 +- lib/CodeGen/CGObjC.cpp | 2 +- lib/CodeGen/CGStmt.cpp | 2 +- lib/CodeGen/CGStmtOpenMP.cpp | 2 +- lib/CodeGen/CodeGenFunction.cpp | 3 +- lib/CodeGen/CodeGenPGO.cpp | 27 +++++++--------- lib/CodeGen/CodeGenPGO.h | 4 +-- test/Profile/cxx-structors.cpp | 32 +++++++++++++++++++ test/Profile/cxx-virtual-destructor-calls.cpp | 27 ++++++++++------ 9 files changed, 67 insertions(+), 34 deletions(-) create mode 100644 test/Profile/cxx-structors.cpp diff --git a/lib/CodeGen/CGBlocks.cpp b/lib/CodeGen/CGBlocks.cpp index 87165fe13a..ba2941e9df 100644 --- a/lib/CodeGen/CGBlocks.cpp +++ b/lib/CodeGen/CGBlocks.cpp @@ -1241,7 +1241,7 @@ CodeGenFunction::GenerateBlockFunction(GlobalDecl GD, if (IsLambdaConversionToBlock) EmitLambdaBlockInvokeBody(); else { - PGO.assignRegionCounters(blockDecl, fn); + PGO.assignRegionCounters(GlobalDecl(blockDecl), fn); incrementProfileCounter(blockDecl->getBody()); EmitStmt(blockDecl->getBody()); } diff --git a/lib/CodeGen/CGObjC.cpp b/lib/CodeGen/CGObjC.cpp index 6865f974fc..2d5991b71f 100644 --- a/lib/CodeGen/CGObjC.cpp +++ b/lib/CodeGen/CGObjC.cpp @@ -557,7 +557,7 @@ static llvm::Value *emitARCRetainLoadOfScalar(CodeGenFunction &CGF, /// its pointer, name, and types registered in the class struture. void CodeGenFunction::GenerateObjCMethod(const ObjCMethodDecl *OMD) { StartObjCMethod(OMD, OMD->getClassInterface()); - PGO.assignRegionCounters(OMD, CurFn); + PGO.assignRegionCounters(GlobalDecl(OMD), CurFn); assert(isa(OMD->getBody())); incrementProfileCounter(OMD->getBody()); EmitCompoundStmtWithoutScope(*cast(OMD->getBody())); diff --git a/lib/CodeGen/CGStmt.cpp b/lib/CodeGen/CGStmt.cpp index 5ebcdf654a..1cbdeffd7c 100644 --- a/lib/CodeGen/CGStmt.cpp +++ b/lib/CodeGen/CGStmt.cpp @@ -2170,7 +2170,7 @@ CodeGenFunction::GenerateCapturedStmtFunction(const CapturedStmt &S) { CXXThisValue = EmitLoadOfLValue(ThisLValue, Loc).getScalarVal(); } - PGO.assignRegionCounters(CD, F); + PGO.assignRegionCounters(GlobalDecl(CD), F); CapturedStmtInfo->EmitBody(*this, CD->getBody()); FinishFunction(CD->getBodyRBrace()); diff --git a/lib/CodeGen/CGStmtOpenMP.cpp b/lib/CodeGen/CGStmtOpenMP.cpp index a6099cabb5..d86cdc7110 100644 --- a/lib/CodeGen/CGStmtOpenMP.cpp +++ b/lib/CodeGen/CGStmtOpenMP.cpp @@ -185,7 +185,7 @@ CodeGenFunction::GenerateOpenMPCapturedStmtFunction(const CapturedStmt &S) { ++Cnt, ++I; } - PGO.assignRegionCounters(CD, F); + PGO.assignRegionCounters(GlobalDecl(CD), F); CapturedStmtInfo->EmitBody(*this, CD->getBody()); FinishFunction(CD->getBodyRBrace()); diff --git a/lib/CodeGen/CodeGenFunction.cpp b/lib/CodeGen/CodeGenFunction.cpp index 31a93e001f..048a04328f 100644 --- a/lib/CodeGen/CodeGenFunction.cpp +++ b/lib/CodeGen/CodeGenFunction.cpp @@ -957,8 +957,7 @@ void CodeGenFunction::GenerateCode(GlobalDecl GD, llvm::Function *Fn, StartFunction(GD, ResTy, Fn, FnInfo, Args, Loc, BodyRange.getBegin()); // Generate the body of the function. - PGO.checkGlobalDecl(GD); - PGO.assignRegionCounters(GD.getDecl(), CurFn); + PGO.assignRegionCounters(GD, CurFn); if (isa(FD)) EmitDestructorBody(Args); else if (isa(FD)) diff --git a/lib/CodeGen/CodeGenPGO.cpp b/lib/CodeGen/CodeGenPGO.cpp index 403380efcb..38774332f3 100644 --- a/lib/CodeGen/CodeGenPGO.cpp +++ b/lib/CodeGen/CodeGenPGO.cpp @@ -605,27 +605,24 @@ uint64_t PGOHash::finalize() { return endian::read(Result); } -void CodeGenPGO::checkGlobalDecl(GlobalDecl GD) { - // Make sure we only emit coverage mapping for one constructor/destructor. - // Clang emits several functions for the constructor and the destructor of - // a class. Every function is instrumented, but we only want to provide - // coverage for one of them. Because of that we only emit the coverage mapping - // for the base constructor/destructor. - if ((isa(GD.getDecl()) && - GD.getCtorType() != Ctor_Base) || - (isa(GD.getDecl()) && - GD.getDtorType() != Dtor_Base)) { - SkipCoverageMapping = true; - } -} - -void CodeGenPGO::assignRegionCounters(const Decl *D, llvm::Function *Fn) { +void CodeGenPGO::assignRegionCounters(GlobalDecl GD, llvm::Function *Fn) { + const Decl *D = GD.getDecl(); bool InstrumentRegions = CGM.getCodeGenOpts().ProfileInstrGenerate; llvm::IndexedInstrProfReader *PGOReader = CGM.getPGOReader(); if (!InstrumentRegions && !PGOReader) return; if (D->isImplicit()) return; + // Constructors and destructors may be represented by several functions in IR. + // If so, instrument only base variant, others are implemented by delegation + // to the base one, it would be counted twice otherwise. + if (CGM.getTarget().getCXXABI().hasConstructorVariants() && + ((isa(GD.getDecl()) && + GD.getCtorType() != Ctor_Base) || + (isa(GD.getDecl()) && + GD.getDtorType() != Dtor_Base))) { + return; + } CGM.ClearUnusedCoverageMapping(D); setFuncName(Fn); diff --git a/lib/CodeGen/CodeGenPGO.h b/lib/CodeGen/CodeGenPGO.h index 350cdcce3e..6bf29ecaa7 100644 --- a/lib/CodeGen/CodeGenPGO.h +++ b/lib/CodeGen/CodeGenPGO.h @@ -78,13 +78,11 @@ public: setCurrentRegionCount(*Count); } - /// Check if we need to emit coverage mapping for a given declaration - void checkGlobalDecl(GlobalDecl GD); /// Assign counters to regions and configure them for PGO of a given /// function. Does nothing if instrumentation is not enabled and either /// generates global variables or associates PGO data with each of the /// counters depending on whether we are generating or using instrumentation. - void assignRegionCounters(const Decl *D, llvm::Function *Fn); + void assignRegionCounters(GlobalDecl GD, llvm::Function *Fn); /// Emit a coverage mapping range with a counter zero /// for an unused declaration. void emitEmptyCounterMapping(const Decl *D, StringRef FuncName, diff --git a/test/Profile/cxx-structors.cpp b/test/Profile/cxx-structors.cpp new file mode 100644 index 0000000000..24c595b863 --- /dev/null +++ b/test/Profile/cxx-structors.cpp @@ -0,0 +1,32 @@ +// Tests for instrumentation of C++ constructors and destructors. +// +// RUN: %clang_cc1 -triple x86_64-apple-macosx10.11.0 -x c++ %s -o - -emit-llvm -fprofile-instr-generate | FileCheck %s + +struct Foo { + Foo() {} + Foo(int) {} + ~Foo() {} +}; + +struct Bar : public Foo { + Bar() {} + Bar(int x) : Foo(x) {} + ~Bar(); +}; + +Foo foo; +Foo foo2(1); +Bar bar; + +// Profile data for complete constructors and destructors must absent. + +// CHECK-NOT: @__llvm_profile_name__ZN3FooC1Ev +// CHECK-NOT: @__llvm_profile_name__ZN3FooC1Ei +// CHECK-NOT: @__llvm_profile_name__ZN3FooD1Ev +// CHECK-NOT: @__llvm_profile_name__ZN3BarC1Ev +// CHECK-NOT: @__llvm_profile_name__ZN3BarD1Ev +// CHECK-NOT: @__llvm_profile_counters__ZN3FooD1Ev +// CHECK-NOT: @__llvm_profile_data__ZN3FooD1Ev + +int main() { +} diff --git a/test/Profile/cxx-virtual-destructor-calls.cpp b/test/Profile/cxx-virtual-destructor-calls.cpp index 35975c2853..d117c21143 100644 --- a/test/Profile/cxx-virtual-destructor-calls.cpp +++ b/test/Profile/cxx-virtual-destructor-calls.cpp @@ -13,18 +13,25 @@ struct B : A { virtual ~B(); }; -// Complete dtor -// CHECK: @__llvm_profile_name__ZN1BD1Ev = private constant [9 x i8] c"_ZN1BD1Ev" +// Base dtor +// CHECK: @__llvm_profile_name__ZN1BD2Ev = private constant [9 x i8] c"_ZN1BD2Ev" -// Deleting dtor -// CHECK: @__llvm_profile_name__ZN1BD0Ev = private constant [9 x i8] c"_ZN1BD0Ev" +// Complete dtor must not be instrumented +// CHECK-NOT: @__llvm_profile_name__ZN1BD1Ev = private constant [9 x i8] c"_ZN1BD1Ev" -// Complete dtor counters and profile data -// CHECK: @__llvm_profile_counters__ZN1BD1Ev = private global [1 x i64] zeroinitializer -// CHECK: @__llvm_profile_data__ZN1BD1Ev = +// Deleting dtor must not be instrumented +// CHECK-NOT: @__llvm_profile_name__ZN1BD0Ev = private constant [9 x i8] c"_ZN1BD0Ev" -// Deleting dtor counters and profile data -// CHECK: @__llvm_profile_counters__ZN1BD0Ev = private global [1 x i64] zeroinitializer -// CHECK: @__llvm_profile_data__ZN1BD0Ev = +// Base dtor counters and profile data +// CHECK: @__llvm_profile_counters__ZN1BD2Ev = private global [1 x i64] zeroinitializer +// CHECK: @__llvm_profile_data__ZN1BD2Ev = + +// Complete dtor counters and profile data must absent +// CHECK-NOT: @__llvm_profile_counters__ZN1BD1Ev = private global [1 x i64] zeroinitializer +// CHECK-NOT: @__llvm_profile_data__ZN1BD1Ev = + +// Deleting dtor counters and profile data must absent +// CHECK-NOT: @__llvm_profile_counters__ZN1BD0Ev = private global [1 x i64] zeroinitializer +// CHECK-NOT: @__llvm_profile_data__ZN1BD0Ev = B::~B() { } -- 2.40.0