diff options
Diffstat (limited to 'contrib/llvm/lib/Support/BlockFrequency.cpp')
-rw-r--r-- | contrib/llvm/lib/Support/BlockFrequency.cpp | 72 |
1 files changed, 72 insertions, 0 deletions
diff --git a/contrib/llvm/lib/Support/BlockFrequency.cpp b/contrib/llvm/lib/Support/BlockFrequency.cpp new file mode 100644 index 0000000..6f7e341 --- /dev/null +++ b/contrib/llvm/lib/Support/BlockFrequency.cpp @@ -0,0 +1,72 @@ +//====--------------- lib/Support/BlockFrequency.cpp -----------*- C++ -*-====// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This file implements Block Frequency class. +// +//===----------------------------------------------------------------------===// + +#include "llvm/Support/BranchProbability.h" +#include "llvm/Support/BlockFrequency.h" +#include "llvm/Support/raw_ostream.h" +#include <cassert> + +using namespace llvm; + +BlockFrequency &BlockFrequency::operator*=(const BranchProbability &Prob) { + Frequency = Prob.scale(Frequency); + return *this; +} + +const BlockFrequency +BlockFrequency::operator*(const BranchProbability &Prob) const { + BlockFrequency Freq(Frequency); + Freq *= Prob; + return Freq; +} + +BlockFrequency &BlockFrequency::operator/=(const BranchProbability &Prob) { + Frequency = Prob.scaleByInverse(Frequency); + return *this; +} + +BlockFrequency BlockFrequency::operator/(const BranchProbability &Prob) const { + BlockFrequency Freq(Frequency); + Freq /= Prob; + return Freq; +} + +BlockFrequency &BlockFrequency::operator+=(const BlockFrequency &Freq) { + uint64_t Before = Freq.Frequency; + Frequency += Freq.Frequency; + + // If overflow, set frequency to the maximum value. + if (Frequency < Before) + Frequency = UINT64_MAX; + + return *this; +} + +const BlockFrequency +BlockFrequency::operator+(const BlockFrequency &Prob) const { + BlockFrequency Freq(Frequency); + Freq += Prob; + return Freq; +} + +BlockFrequency &BlockFrequency::operator>>=(const unsigned count) { + // Frequency can never be 0 by design. + assert(Frequency != 0); + + // Shift right by count. + Frequency >>= count; + + // Saturate to 1 if we are 0. + Frequency |= Frequency == 0; + return *this; +} |