1 //====--------------- lib/Support/BlockFrequency.cpp -----------*- C++ -*-====//
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-exception
7 //===----------------------------------------------------------------------===//
9 // This file implements Block Frequency class.
11 //===----------------------------------------------------------------------===//
13 #include "llvm/Support/BlockFrequency.h"
18 BlockFrequency &BlockFrequency::operator*=(BranchProbability Prob) {
19 Frequency = Prob.scale(Frequency);
23 BlockFrequency BlockFrequency::operator*(BranchProbability Prob) const {
24 BlockFrequency Freq(Frequency);
29 BlockFrequency &BlockFrequency::operator/=(BranchProbability Prob) {
30 Frequency = Prob.scaleByInverse(Frequency);
34 BlockFrequency BlockFrequency::operator/(BranchProbability Prob) const {
35 BlockFrequency Freq(Frequency);
40 BlockFrequency &BlockFrequency::operator+=(BlockFrequency Freq) {
41 uint64_t Before = Freq.Frequency;
42 Frequency += Freq.Frequency;
44 // If overflow, set frequency to the maximum value.
45 if (Frequency < Before)
46 Frequency = UINT64_MAX;
51 BlockFrequency BlockFrequency::operator+(BlockFrequency Freq) const {
52 BlockFrequency NewFreq(Frequency);
57 BlockFrequency &BlockFrequency::operator-=(BlockFrequency Freq) {
58 // If underflow, set frequency to 0.
59 if (Frequency <= Freq.Frequency)
62 Frequency -= Freq.Frequency;
66 BlockFrequency BlockFrequency::operator-(BlockFrequency Freq) const {
67 BlockFrequency NewFreq(Frequency);
72 BlockFrequency &BlockFrequency::operator>>=(const unsigned count) {
73 // Frequency can never be 0 by design.
74 assert(Frequency != 0);
76 // Shift right by count.
79 // Saturate to 1 if we are 0.
80 Frequency |= Frequency == 0;