99 lines · cpp
1//===- BlockFrequencyInfoTest.cpp - BlockFrequencyInfo unit tests ---------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9#include "llvm/Analysis/BlockFrequencyInfo.h"10#include "llvm/Analysis/BlockFrequencyInfoImpl.h"11#include "llvm/Analysis/BranchProbabilityInfo.h"12#include "llvm/Analysis/LoopInfo.h"13#include "llvm/AsmParser/Parser.h"14#include "llvm/IR/BasicBlock.h"15#include "llvm/IR/Dominators.h"16#include "llvm/IR/Function.h"17#include "llvm/IR/LLVMContext.h"18#include "llvm/IR/Module.h"19#include "llvm/Support/DataTypes.h"20#include "llvm/Support/SourceMgr.h"21#include "llvm/Support/raw_ostream.h"22#include "gtest/gtest.h"23 24namespace llvm {25namespace {26 27class BlockFrequencyInfoTest : public testing::Test {28protected:29 std::unique_ptr<BranchProbabilityInfo> BPI;30 std::unique_ptr<DominatorTree> DT;31 std::unique_ptr<LoopInfo> LI;32 LLVMContext C;33 34 BlockFrequencyInfo buildBFI(Function &F) {35 DT.reset(new DominatorTree(F));36 LI.reset(new LoopInfo(*DT));37 BPI.reset(new BranchProbabilityInfo(F, *LI));38 return BlockFrequencyInfo(F, *BPI, *LI);39 }40 std::unique_ptr<Module> makeLLVMModule() {41 const char *ModuleStrig = "define i32 @f(i32 %x) {\n"42 "bb0:\n"43 " %y1 = icmp eq i32 %x, 0 \n"44 " br i1 %y1, label %bb1, label %bb2 \n"45 "bb1:\n"46 " br label %bb3\n"47 "bb2:\n"48 " br label %bb3\n"49 "bb3:\n"50 " %y2 = phi i32 [0, %bb1], [1, %bb2] \n"51 " ret i32 %y2\n"52 "}\n";53 SMDiagnostic Err;54 return parseAssemblyString(ModuleStrig, Err, C);55 }56};57 58TEST_F(BlockFrequencyInfoTest, Basic) {59 auto M = makeLLVMModule();60 Function *F = M->getFunction("f");61 F->setEntryCount(100);62 63 BlockFrequencyInfo BFI = buildBFI(*F);64 BasicBlock &BB0 = F->getEntryBlock();65 BasicBlock *BB1 = BB0.getTerminator()->getSuccessor(0);66 BasicBlock *BB2 = BB0.getTerminator()->getSuccessor(1);67 BasicBlock *BB3 = BB1->getSingleSuccessor();68 69 uint64_t BB0Freq = BFI.getBlockFreq(&BB0).getFrequency();70 uint64_t BB1Freq = BFI.getBlockFreq(BB1).getFrequency();71 uint64_t BB2Freq = BFI.getBlockFreq(BB2).getFrequency();72 uint64_t BB3Freq = BFI.getBlockFreq(BB3).getFrequency();73 74 EXPECT_EQ(BB0Freq, BB3Freq);75 EXPECT_EQ(BB0Freq, BB1Freq + BB2Freq);76 EXPECT_EQ(BB0Freq, BB3Freq);77 78 EXPECT_EQ(*BFI.getBlockProfileCount(&BB0), UINT64_C(100));79 EXPECT_EQ(*BFI.getBlockProfileCount(BB3), UINT64_C(100));80 EXPECT_EQ(*BFI.getBlockProfileCount(BB1),81 (100 * BB1Freq + BB0Freq / 2) / BB0Freq);82 EXPECT_EQ(*BFI.getBlockProfileCount(BB2),83 (100 * BB2Freq + BB0Freq / 2) / BB0Freq);84 85 // Scale the frequencies of BB0, BB1 and BB2 by a factor of two.86 SmallPtrSet<BasicBlock *, 4> BlocksToScale({BB1, BB2});87 BFI.setBlockFreqAndScale(&BB0, BlockFrequency(BB0Freq * 2), BlocksToScale);88 EXPECT_EQ(BFI.getBlockFreq(&BB0).getFrequency(), 2 * BB0Freq);89 EXPECT_EQ(BFI.getBlockFreq(BB1).getFrequency(), 2 * BB1Freq);90 EXPECT_EQ(BFI.getBlockFreq(BB2).getFrequency(), 2 * BB2Freq);91 EXPECT_EQ(BFI.getBlockFreq(BB3).getFrequency(), BB3Freq);92}93 94static_assert(std::is_trivially_copyable_v<bfi_detail::BlockMass>,95 "trivially copyable");96 97} // end anonymous namespace98} // end namespace llvm99