From d7648ff20f8bbc8217a26576ca96addc55e003de Mon Sep 17 00:00:00 2001 From: Jakob Stoklund Olesen Date: Fri, 28 Jun 2013 18:23:42 +0000 Subject: Add a division operator to BlockFrequency. Allow a BlockFrequency to be divided by a non-zero BranchProbability with saturating arithmetic. This will be used to compute the frequency of a loop header given the probability of leaving the loop. Our long division algorithm already saturates on overflow, so that was a freebie. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@185184 91177308-0d34-0410-b5e6-96231b3b80d8 --- unittests/Support/BlockFrequencyTest.cpp | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) (limited to 'unittests') diff --git a/unittests/Support/BlockFrequencyTest.cpp b/unittests/Support/BlockFrequencyTest.cpp index ff66bc4e45..4bcddfebd9 100644 --- a/unittests/Support/BlockFrequencyTest.cpp +++ b/unittests/Support/BlockFrequencyTest.cpp @@ -52,6 +52,24 @@ TEST(BlockFrequencyTest, MaxToMax) { EXPECT_EQ(Freq.getFrequency(), UINT64_MAX); } +TEST(BlockFrequency, Divide) { + BlockFrequency Freq(0x3333333333333333ULL); + Freq /= BranchProbability(1, 2); + EXPECT_EQ(Freq.getFrequency(), 0x6666666666666666ULL); +} + +TEST(BlockFrequencyTest, Saturate) { + BlockFrequency Freq(0x3333333333333333ULL); + Freq /= BranchProbability(100, 300); + EXPECT_EQ(Freq.getFrequency(), 0x9999999999999999ULL); + Freq /= BranchProbability(1, 2); + EXPECT_EQ(Freq.getFrequency(), UINT64_MAX); + + Freq = 0x1000000000000000ULL; + Freq /= BranchProbability(10000, 160000); + EXPECT_EQ(Freq.getFrequency(), UINT64_MAX); +} + TEST(BlockFrequencyTest, ProbabilityCompare) { BranchProbability A(4, 5); BranchProbability B(4U << 29, 5U << 29); -- cgit v1.2.3