1 //===- BlockFrequencyInfoTest.cpp - BlockFrequencyInfo unit tests ---------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 #include "llvm/Analysis/BlockFrequencyInfo.h"
11 #include "llvm/Analysis/BlockFrequencyInfoImpl.h"
12 #include "llvm/Analysis/BranchProbabilityInfo.h"
13 #include "llvm/Analysis/LoopInfo.h"
14 #include "llvm/AsmParser/Parser.h"
15 #include "llvm/IR/BasicBlock.h"
16 #include "llvm/IR/Dominators.h"
17 #include "llvm/IR/Function.h"
18 #include "llvm/IR/LLVMContext.h"
19 #include "llvm/IR/Module.h"
20 #include "llvm/Support/DataTypes.h"
21 #include "llvm/Support/SourceMgr.h"
22 #include "llvm/Support/raw_ostream.h"
23 #include "gtest/gtest.h"
28 class BlockFrequencyInfoTest : public testing::Test {
30 std::unique_ptr<BranchProbabilityInfo> BPI;
31 std::unique_ptr<DominatorTree> DT;
32 std::unique_ptr<LoopInfo> LI;
35 BlockFrequencyInfo buildBFI(Function &F) {
36 DT.reset(new DominatorTree(F));
37 LI.reset(new LoopInfo(*DT));
38 BPI.reset(new BranchProbabilityInfo(F, *LI));
39 return BlockFrequencyInfo(F, *BPI, *LI);
41 std::unique_ptr<Module> makeLLVMModule() {
42 const char *ModuleStrig = "define i32 @f(i32 %x) {\n"
44 " %y1 = icmp eq i32 %x, 0 \n"
45 " br i1 %y1, label %bb1, label %bb2 \n"
51 " %y2 = phi i32 [0, %bb1], [1, %bb2] \n"
55 return parseAssemblyString(ModuleStrig, Err, C);
59 TEST_F(BlockFrequencyInfoTest, Basic) {
60 auto M = makeLLVMModule();
61 Function *F = M->getFunction("f");
62 F->setEntryCount(100);
64 BlockFrequencyInfo BFI = buildBFI(*F);
65 BasicBlock &BB0 = F->getEntryBlock();
66 BasicBlock *BB1 = BB0.getTerminator()->getSuccessor(0);
67 BasicBlock *BB2 = BB0.getTerminator()->getSuccessor(1);
68 BasicBlock *BB3 = BB1->getSingleSuccessor();
70 uint64_t BB0Freq = BFI.getBlockFreq(&BB0).getFrequency();
71 uint64_t BB1Freq = BFI.getBlockFreq(BB1).getFrequency();
72 uint64_t BB2Freq = BFI.getBlockFreq(BB2).getFrequency();
73 uint64_t BB3Freq = BFI.getBlockFreq(BB3).getFrequency();
75 EXPECT_EQ(BB0Freq, BB3Freq);
76 EXPECT_EQ(BB0Freq, BB1Freq + BB2Freq);
77 EXPECT_EQ(BB0Freq, BB3Freq);
79 EXPECT_EQ(BFI.getBlockProfileCount(&BB0).getValue(), UINT64_C(100));
80 EXPECT_EQ(BFI.getBlockProfileCount(BB3).getValue(), UINT64_C(100));
81 EXPECT_EQ(BFI.getBlockProfileCount(BB1).getValue(), 100 * BB1Freq / BB0Freq);
82 EXPECT_EQ(BFI.getBlockProfileCount(BB2).getValue(), 100 * BB2Freq / BB0Freq);
84 // Scale the frequencies of BB0, BB1 and BB2 by a factor of two.
85 SmallPtrSet<BasicBlock *, 4> BlocksToScale({BB1, BB2});
86 BFI.setBlockFreqAndScale(&BB0, BB0Freq * 2, BlocksToScale);
87 EXPECT_EQ(BFI.getBlockFreq(&BB0).getFrequency(), 2 * BB0Freq);
88 EXPECT_EQ(BFI.getBlockFreq(BB1).getFrequency(), 2 * BB1Freq);
89 EXPECT_EQ(BFI.getBlockFreq(BB2).getFrequency(), 2 * BB2Freq);
90 EXPECT_EQ(BFI.getBlockFreq(BB3).getFrequency(), BB3Freq);
93 } // end anonymous namespace
94 } // end namespace llvm