llvm-for-llvmta/unittests/Analysis/ProfileSummaryInfoTest.cpp

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2022-04-25 10:02:23 +02:00
//===- ProfileSummaryInfoTest.cpp - ProfileSummaryInfo unit tests ---------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include "llvm/Analysis/ProfileSummaryInfo.h"
#include "llvm/Analysis/BlockFrequencyInfo.h"
#include "llvm/Analysis/BranchProbabilityInfo.h"
#include "llvm/Analysis/LoopInfo.h"
#include "llvm/AsmParser/Parser.h"
#include "llvm/IR/BasicBlock.h"
#include "llvm/IR/Dominators.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/MDBuilder.h"
#include "llvm/IR/Module.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/DataTypes.h"
#include "llvm/Support/FormatVariadic.h"
#include "llvm/Support/SourceMgr.h"
#include "llvm/Support/raw_ostream.h"
#include "gtest/gtest.h"
extern llvm::cl::opt<bool> ScalePartialSampleProfileWorkingSetSize;
namespace llvm {
namespace {
class ProfileSummaryInfoTest : public testing::Test {
protected:
LLVMContext C;
std::unique_ptr<BranchProbabilityInfo> BPI;
std::unique_ptr<DominatorTree> DT;
std::unique_ptr<LoopInfo> LI;
ProfileSummaryInfo buildPSI(Module *M) {
return ProfileSummaryInfo(*M);
}
BlockFrequencyInfo buildBFI(Function &F) {
DT.reset(new DominatorTree(F));
LI.reset(new LoopInfo(*DT));
BPI.reset(new BranchProbabilityInfo(F, *LI));
return BlockFrequencyInfo(F, *BPI, *LI);
}
std::unique_ptr<Module> makeLLVMModule(const char *ProfKind = nullptr,
uint64_t NumCounts = 3,
uint64_t IsPartialProfile = 0,
double PartialProfileRatio = 0.0,
uint64_t HotNumCounts = 3,
uint64_t ColdNumCounts = 10) {
const char *ModuleString =
"define i32 @g(i32 %x) !prof !21 {{\n"
" ret i32 0\n"
"}\n"
"define i32 @h(i32 %x) !prof !22 {{\n"
" ret i32 0\n"
"}\n"
"define i32 @f(i32 %x) !prof !20 {{\n"
"bb0:\n"
" %y1 = icmp eq i32 %x, 0 \n"
" br i1 %y1, label %bb1, label %bb2, !prof !23 \n"
"bb1:\n"
" %z1 = call i32 @g(i32 %x)\n"
" br label %bb3\n"
"bb2:\n"
" %z2 = call i32 @h(i32 %x)\n"
" br label %bb3\n"
"bb3:\n"
" %y2 = phi i32 [0, %bb1], [1, %bb2] \n"
" ret i32 %y2\n"
"}\n"
"define i32 @l(i32 %x) {{\n"
"bb0:\n"
" %y1 = icmp eq i32 %x, 0 \n"
" br i1 %y1, label %bb1, label %bb2, !prof !23 \n"
"bb1:\n"
" %z1 = call i32 @g(i32 %x)\n"
" br label %bb3\n"
"bb2:\n"
" %z2 = call i32 @h(i32 %x)\n"
" br label %bb3\n"
"bb3:\n"
" %y2 = phi i32 [0, %bb1], [1, %bb2] \n"
" ret i32 %y2\n"
"}\n"
"!20 = !{{!\"function_entry_count\", i64 400}\n"
"!21 = !{{!\"function_entry_count\", i64 1}\n"
"!22 = !{{!\"function_entry_count\", i64 100}\n"
"!23 = !{{!\"branch_weights\", i32 64, i32 4}\n"
"{0}";
const char *SummaryString =
"!llvm.module.flags = !{{!1}\n"
"!1 = !{{i32 1, !\"ProfileSummary\", !2}\n"
"!2 = !{{!3, !4, !5, !6, !7, !8, !9, !10, !11, !12}\n"
"!3 = !{{!\"ProfileFormat\", !\"{0}\"}\n"
"!4 = !{{!\"TotalCount\", i64 10000}\n"
"!5 = !{{!\"MaxCount\", i64 10}\n"
"!6 = !{{!\"MaxInternalCount\", i64 1}\n"
"!7 = !{{!\"MaxFunctionCount\", i64 1000}\n"
"!8 = !{{!\"NumCounts\", i64 {1}}\n"
"!9 = !{{!\"NumFunctions\", i64 3}\n"
"!10 = !{{!\"IsPartialProfile\", i64 {2}}\n"
"!11 = !{{!\"PartialProfileRatio\", double {3}}\n"
"!12 = !{{!\"DetailedSummary\", !13}\n"
"!13 = !{{!14, !15, !16}\n"
"!14 = !{{i32 10000, i64 1000, i32 1}\n"
"!15 = !{{i32 990000, i64 300, i32 {4}}\n"
"!16 = !{{i32 999999, i64 5, i32 {5}}\n";
SMDiagnostic Err;
if (ProfKind) {
auto Summary =
formatv(SummaryString, ProfKind, NumCounts, IsPartialProfile,
PartialProfileRatio, HotNumCounts, ColdNumCounts)
.str();
return parseAssemblyString(formatv(ModuleString, Summary).str(), Err, C);
} else
return parseAssemblyString(formatv(ModuleString, "").str(), Err, C);
}
};
TEST_F(ProfileSummaryInfoTest, TestNoProfile) {
auto M = makeLLVMModule(/*ProfKind=*/nullptr);
Function *F = M->getFunction("f");
ProfileSummaryInfo PSI = buildPSI(M.get());
EXPECT_FALSE(PSI.hasProfileSummary());
EXPECT_FALSE(PSI.hasSampleProfile());
EXPECT_FALSE(PSI.hasInstrumentationProfile());
// In the absence of profiles, is{Hot|Cold}X methods should always return
// false.
EXPECT_FALSE(PSI.isHotCount(1000));
EXPECT_FALSE(PSI.isHotCount(0));
EXPECT_FALSE(PSI.isColdCount(1000));
EXPECT_FALSE(PSI.isColdCount(0));
EXPECT_FALSE(PSI.isFunctionEntryHot(F));
EXPECT_FALSE(PSI.isFunctionEntryCold(F));
BasicBlock &BB0 = F->getEntryBlock();
BasicBlock *BB1 = BB0.getTerminator()->getSuccessor(0);
BlockFrequencyInfo BFI = buildBFI(*F);
EXPECT_FALSE(PSI.isHotBlock(&BB0, &BFI));
EXPECT_FALSE(PSI.isColdBlock(&BB0, &BFI));
CallBase &CS1 = cast<CallBase>(*BB1->getFirstNonPHI());
EXPECT_FALSE(PSI.isHotCallSite(CS1, &BFI));
EXPECT_FALSE(PSI.isColdCallSite(CS1, &BFI));
}
TEST_F(ProfileSummaryInfoTest, TestCommon) {
auto M = makeLLVMModule("InstrProf");
Function *F = M->getFunction("f");
Function *G = M->getFunction("g");
Function *H = M->getFunction("h");
ProfileSummaryInfo PSI = buildPSI(M.get());
EXPECT_TRUE(PSI.hasProfileSummary());
EXPECT_TRUE(PSI.isHotCount(400));
EXPECT_TRUE(PSI.isColdCount(2));
EXPECT_FALSE(PSI.isColdCount(100));
EXPECT_FALSE(PSI.isHotCount(100));
EXPECT_TRUE(PSI.isHotCountNthPercentile(990000, 400));
EXPECT_FALSE(PSI.isHotCountNthPercentile(990000, 100));
EXPECT_FALSE(PSI.isHotCountNthPercentile(990000, 2));
EXPECT_FALSE(PSI.isColdCountNthPercentile(990000, 400));
EXPECT_TRUE(PSI.isColdCountNthPercentile(990000, 100));
EXPECT_TRUE(PSI.isColdCountNthPercentile(990000, 2));
EXPECT_TRUE(PSI.isHotCountNthPercentile(999999, 400));
EXPECT_TRUE(PSI.isHotCountNthPercentile(999999, 100));
EXPECT_FALSE(PSI.isHotCountNthPercentile(999999, 2));
EXPECT_FALSE(PSI.isColdCountNthPercentile(999999, 400));
EXPECT_FALSE(PSI.isColdCountNthPercentile(999999, 100));
EXPECT_TRUE(PSI.isColdCountNthPercentile(999999, 2));
EXPECT_FALSE(PSI.isHotCountNthPercentile(10000, 400));
EXPECT_FALSE(PSI.isHotCountNthPercentile(10000, 100));
EXPECT_FALSE(PSI.isHotCountNthPercentile(10000, 2));
EXPECT_TRUE(PSI.isColdCountNthPercentile(10000, 400));
EXPECT_TRUE(PSI.isColdCountNthPercentile(10000, 100));
EXPECT_TRUE(PSI.isColdCountNthPercentile(10000, 2));
EXPECT_TRUE(PSI.isFunctionEntryHot(F));
EXPECT_FALSE(PSI.isFunctionEntryHot(G));
EXPECT_FALSE(PSI.isFunctionEntryHot(H));
}
TEST_F(ProfileSummaryInfoTest, InstrProf) {
auto M = makeLLVMModule("InstrProf");
Function *F = M->getFunction("f");
ProfileSummaryInfo PSI = buildPSI(M.get());
EXPECT_TRUE(PSI.hasProfileSummary());
EXPECT_TRUE(PSI.hasInstrumentationProfile());
BasicBlock &BB0 = F->getEntryBlock();
BasicBlock *BB1 = BB0.getTerminator()->getSuccessor(0);
BasicBlock *BB2 = BB0.getTerminator()->getSuccessor(1);
BasicBlock *BB3 = BB1->getSingleSuccessor();
BlockFrequencyInfo BFI = buildBFI(*F);
EXPECT_TRUE(PSI.isHotBlock(&BB0, &BFI));
EXPECT_TRUE(PSI.isHotBlock(BB1, &BFI));
EXPECT_FALSE(PSI.isHotBlock(BB2, &BFI));
EXPECT_TRUE(PSI.isHotBlock(BB3, &BFI));
EXPECT_TRUE(PSI.isHotBlockNthPercentile(990000, &BB0, &BFI));
EXPECT_TRUE(PSI.isHotBlockNthPercentile(990000, BB1, &BFI));
EXPECT_FALSE(PSI.isHotBlockNthPercentile(990000, BB2, &BFI));
EXPECT_TRUE(PSI.isHotBlockNthPercentile(990000, BB3, &BFI));
EXPECT_FALSE(PSI.isColdBlockNthPercentile(990000, &BB0, &BFI));
EXPECT_FALSE(PSI.isColdBlockNthPercentile(990000, BB1, &BFI));
EXPECT_TRUE(PSI.isColdBlockNthPercentile(990000, BB2, &BFI));
EXPECT_FALSE(PSI.isColdBlockNthPercentile(990000, BB3, &BFI));
EXPECT_TRUE(PSI.isHotBlockNthPercentile(999900, &BB0, &BFI));
EXPECT_TRUE(PSI.isHotBlockNthPercentile(999900, BB1, &BFI));
EXPECT_TRUE(PSI.isHotBlockNthPercentile(999900, BB2, &BFI));
EXPECT_TRUE(PSI.isHotBlockNthPercentile(999900, BB3, &BFI));
EXPECT_FALSE(PSI.isColdBlockNthPercentile(999900, &BB0, &BFI));
EXPECT_FALSE(PSI.isColdBlockNthPercentile(999900, BB1, &BFI));
EXPECT_FALSE(PSI.isColdBlockNthPercentile(999900, BB2, &BFI));
EXPECT_FALSE(PSI.isColdBlockNthPercentile(999900, BB3, &BFI));
EXPECT_FALSE(PSI.isHotBlockNthPercentile(10000, &BB0, &BFI));
EXPECT_FALSE(PSI.isHotBlockNthPercentile(10000, BB1, &BFI));
EXPECT_FALSE(PSI.isHotBlockNthPercentile(10000, BB2, &BFI));
EXPECT_FALSE(PSI.isHotBlockNthPercentile(10000, BB3, &BFI));
EXPECT_TRUE(PSI.isColdBlockNthPercentile(10000, &BB0, &BFI));
EXPECT_TRUE(PSI.isColdBlockNthPercentile(10000, BB1, &BFI));
EXPECT_TRUE(PSI.isColdBlockNthPercentile(10000, BB2, &BFI));
EXPECT_TRUE(PSI.isColdBlockNthPercentile(10000, BB3, &BFI));
CallBase &CS1 = cast<CallBase>(*BB1->getFirstNonPHI());
auto *CI2 = BB2->getFirstNonPHI();
CallBase &CS2 = cast<CallBase>(*CI2);
EXPECT_TRUE(PSI.isHotCallSite(CS1, &BFI));
EXPECT_FALSE(PSI.isHotCallSite(CS2, &BFI));
// Test that adding an MD_prof metadata with a hot count on CS2 does not
// change its hotness as it has no effect in instrumented profiling.
MDBuilder MDB(M->getContext());
CI2->setMetadata(llvm::LLVMContext::MD_prof, MDB.createBranchWeights({400}));
EXPECT_FALSE(PSI.isHotCallSite(CS2, &BFI));
EXPECT_TRUE(PSI.isFunctionHotInCallGraphNthPercentile(990000, F, BFI));
EXPECT_FALSE(PSI.isFunctionColdInCallGraphNthPercentile(990000, F, BFI));
EXPECT_FALSE(PSI.isFunctionHotInCallGraphNthPercentile(10000, F, BFI));
EXPECT_TRUE(PSI.isFunctionColdInCallGraphNthPercentile(10000, F, BFI));
}
TEST_F(ProfileSummaryInfoTest, InstrProfNoFuncEntryCount) {
auto M = makeLLVMModule("InstrProf");
Function *F = M->getFunction("l");
ProfileSummaryInfo PSI = buildPSI(M.get());
EXPECT_TRUE(PSI.hasProfileSummary());
EXPECT_TRUE(PSI.hasInstrumentationProfile());
BasicBlock &BB0 = F->getEntryBlock();
BasicBlock *BB1 = BB0.getTerminator()->getSuccessor(0);
BasicBlock *BB2 = BB0.getTerminator()->getSuccessor(1);
BasicBlock *BB3 = BB1->getSingleSuccessor();
BlockFrequencyInfo BFI = buildBFI(*F);
// Without the entry count, all should return false.
EXPECT_FALSE(PSI.isHotBlockNthPercentile(990000, &BB0, &BFI));
EXPECT_FALSE(PSI.isHotBlockNthPercentile(990000, BB1, &BFI));
EXPECT_FALSE(PSI.isHotBlockNthPercentile(990000, BB2, &BFI));
EXPECT_FALSE(PSI.isHotBlockNthPercentile(990000, BB3, &BFI));
EXPECT_FALSE(PSI.isColdBlockNthPercentile(990000, &BB0, &BFI));
EXPECT_FALSE(PSI.isColdBlockNthPercentile(990000, BB1, &BFI));
EXPECT_FALSE(PSI.isColdBlockNthPercentile(990000, BB2, &BFI));
EXPECT_FALSE(PSI.isColdBlockNthPercentile(990000, BB3, &BFI));
EXPECT_FALSE(PSI.isFunctionHotInCallGraphNthPercentile(990000, F, BFI));
EXPECT_FALSE(PSI.isFunctionColdInCallGraphNthPercentile(990000, F, BFI));
}
TEST_F(ProfileSummaryInfoTest, SampleProf) {
auto M = makeLLVMModule("SampleProfile");
Function *F = M->getFunction("f");
ProfileSummaryInfo PSI = buildPSI(M.get());
EXPECT_TRUE(PSI.hasProfileSummary());
EXPECT_TRUE(PSI.hasSampleProfile());
EXPECT_FALSE(PSI.hasPartialSampleProfile());
BasicBlock &BB0 = F->getEntryBlock();
BasicBlock *BB1 = BB0.getTerminator()->getSuccessor(0);
BasicBlock *BB2 = BB0.getTerminator()->getSuccessor(1);
BasicBlock *BB3 = BB1->getSingleSuccessor();
BlockFrequencyInfo BFI = buildBFI(*F);
EXPECT_TRUE(PSI.isHotBlock(&BB0, &BFI));
EXPECT_TRUE(PSI.isHotBlock(BB1, &BFI));
EXPECT_FALSE(PSI.isHotBlock(BB2, &BFI));
EXPECT_TRUE(PSI.isHotBlock(BB3, &BFI));
EXPECT_TRUE(PSI.isHotBlockNthPercentile(990000, &BB0, &BFI));
EXPECT_TRUE(PSI.isHotBlockNthPercentile(990000, BB1, &BFI));
EXPECT_FALSE(PSI.isHotBlockNthPercentile(990000, BB2, &BFI));
EXPECT_TRUE(PSI.isHotBlockNthPercentile(990000, BB3, &BFI));
EXPECT_FALSE(PSI.isColdBlockNthPercentile(990000, &BB0, &BFI));
EXPECT_FALSE(PSI.isColdBlockNthPercentile(990000, BB1, &BFI));
EXPECT_TRUE(PSI.isColdBlockNthPercentile(990000, BB2, &BFI));
EXPECT_FALSE(PSI.isColdBlockNthPercentile(990000, BB3, &BFI));
EXPECT_TRUE(PSI.isHotBlockNthPercentile(999900, &BB0, &BFI));
EXPECT_TRUE(PSI.isHotBlockNthPercentile(999900, BB1, &BFI));
EXPECT_TRUE(PSI.isHotBlockNthPercentile(999900, BB2, &BFI));
EXPECT_TRUE(PSI.isHotBlockNthPercentile(999900, BB3, &BFI));
EXPECT_FALSE(PSI.isColdBlockNthPercentile(999900, &BB0, &BFI));
EXPECT_FALSE(PSI.isColdBlockNthPercentile(999900, BB1, &BFI));
EXPECT_FALSE(PSI.isColdBlockNthPercentile(999900, BB2, &BFI));
EXPECT_FALSE(PSI.isColdBlockNthPercentile(999900, BB3, &BFI));
EXPECT_FALSE(PSI.isHotBlockNthPercentile(10000, &BB0, &BFI));
EXPECT_FALSE(PSI.isHotBlockNthPercentile(10000, BB1, &BFI));
EXPECT_FALSE(PSI.isHotBlockNthPercentile(10000, BB2, &BFI));
EXPECT_FALSE(PSI.isHotBlockNthPercentile(10000, BB3, &BFI));
EXPECT_TRUE(PSI.isColdBlockNthPercentile(10000, &BB0, &BFI));
EXPECT_TRUE(PSI.isColdBlockNthPercentile(10000, BB1, &BFI));
EXPECT_TRUE(PSI.isColdBlockNthPercentile(10000, BB2, &BFI));
EXPECT_TRUE(PSI.isColdBlockNthPercentile(10000, BB3, &BFI));
CallBase &CS1 = cast<CallBase>(*BB1->getFirstNonPHI());
auto *CI2 = BB2->getFirstNonPHI();
// Manually attach branch weights metadata to the call instruction.
SmallVector<uint32_t, 1> Weights;
Weights.push_back(1000);
MDBuilder MDB(M->getContext());
CI2->setMetadata(LLVMContext::MD_prof, MDB.createBranchWeights(Weights));
CallBase &CS2 = cast<CallBase>(*CI2);
EXPECT_FALSE(PSI.isHotCallSite(CS1, &BFI));
EXPECT_TRUE(PSI.isHotCallSite(CS2, &BFI));
// Test that CS2 is considered hot when it gets an MD_prof metadata with
// weights that exceed the hot count threshold.
CI2->setMetadata(llvm::LLVMContext::MD_prof, MDB.createBranchWeights({400}));
EXPECT_TRUE(PSI.isHotCallSite(CS2, &BFI));
EXPECT_TRUE(PSI.isFunctionHotInCallGraphNthPercentile(990000, F, BFI));
EXPECT_FALSE(PSI.isFunctionColdInCallGraphNthPercentile(990000, F, BFI));
EXPECT_FALSE(PSI.isFunctionHotInCallGraphNthPercentile(10000, F, BFI));
EXPECT_TRUE(PSI.isFunctionColdInCallGraphNthPercentile(10000, F, BFI));
}
TEST_F(ProfileSummaryInfoTest, SampleProfNoFuncEntryCount) {
auto M = makeLLVMModule("SampleProfile");
Function *F = M->getFunction("l");
ProfileSummaryInfo PSI = buildPSI(M.get());
EXPECT_TRUE(PSI.hasProfileSummary());
EXPECT_TRUE(PSI.hasSampleProfile());
BasicBlock &BB0 = F->getEntryBlock();
BasicBlock *BB1 = BB0.getTerminator()->getSuccessor(0);
BasicBlock *BB2 = BB0.getTerminator()->getSuccessor(1);
BasicBlock *BB3 = BB1->getSingleSuccessor();
BlockFrequencyInfo BFI = buildBFI(*F);
// Without the entry count, all should return false.
EXPECT_FALSE(PSI.isHotBlockNthPercentile(990000, &BB0, &BFI));
EXPECT_FALSE(PSI.isHotBlockNthPercentile(990000, BB1, &BFI));
EXPECT_FALSE(PSI.isHotBlockNthPercentile(990000, BB2, &BFI));
EXPECT_FALSE(PSI.isHotBlockNthPercentile(990000, BB3, &BFI));
EXPECT_FALSE(PSI.isColdBlockNthPercentile(990000, &BB0, &BFI));
EXPECT_FALSE(PSI.isColdBlockNthPercentile(990000, BB1, &BFI));
EXPECT_FALSE(PSI.isColdBlockNthPercentile(990000, BB2, &BFI));
EXPECT_FALSE(PSI.isColdBlockNthPercentile(990000, BB3, &BFI));
EXPECT_FALSE(PSI.isFunctionHotInCallGraphNthPercentile(990000, F, BFI));
EXPECT_FALSE(PSI.isFunctionColdInCallGraphNthPercentile(990000, F, BFI));
}
TEST_F(ProfileSummaryInfoTest, PartialSampleProfWorkingSetSize) {
ScalePartialSampleProfileWorkingSetSize.setValue(true);
// With PartialProfileRatio unset (zero.)
auto M1 = makeLLVMModule("SampleProfile", /*NumCounts*/ 3,
/*IsPartialProfile*/ 1,
/*PartialProfileRatio*/ 0.0,
/*HotNumCounts*/ 3, /*ColdNumCounts*/ 10);
ProfileSummaryInfo PSI1 = buildPSI(M1.get());
EXPECT_TRUE(PSI1.hasProfileSummary());
EXPECT_TRUE(PSI1.hasSampleProfile());
EXPECT_TRUE(PSI1.hasPartialSampleProfile());
EXPECT_FALSE(PSI1.hasHugeWorkingSetSize());
EXPECT_FALSE(PSI1.hasLargeWorkingSetSize());
// With PartialProfileRatio set (non-zero) and a small working set size.
auto M2 = makeLLVMModule("SampleProfile", /*NumCounts*/ 27493235,
/*IsPartialProfile*/ 1,
/*PartialProfileRatio*/ 0.00000012,
/*HotNumCounts*/ 3102082,
/*ColdNumCounts*/ 18306149);
ProfileSummaryInfo PSI2 = buildPSI(M2.get());
EXPECT_TRUE(PSI2.hasProfileSummary());
EXPECT_TRUE(PSI2.hasSampleProfile());
EXPECT_TRUE(PSI2.hasPartialSampleProfile());
EXPECT_FALSE(PSI2.hasHugeWorkingSetSize());
EXPECT_FALSE(PSI2.hasLargeWorkingSetSize());
// With PartialProfileRatio is set (non-zero) and a large working set size.
auto M3 = makeLLVMModule("SampleProfile", /*NumCounts*/ 27493235,
/*IsPartialProfile*/ 1,
/*PartialProfileRatio*/ 0.9,
/*HotNumCounts*/ 3102082,
/*ColdNumCounts*/ 18306149);
ProfileSummaryInfo PSI3 = buildPSI(M3.get());
EXPECT_TRUE(PSI3.hasProfileSummary());
EXPECT_TRUE(PSI3.hasSampleProfile());
EXPECT_TRUE(PSI3.hasPartialSampleProfile());
EXPECT_TRUE(PSI3.hasHugeWorkingSetSize());
EXPECT_TRUE(PSI3.hasLargeWorkingSetSize());
}
} // end anonymous namespace
} // end namespace llvm