1 files changed, 82 insertions, 0 deletions
diff --git a/llvm/lib/Support/BlockFrequency.cpp b/llvm/lib/Support/BlockFrequency.cpp
new file mode 100644
index 000000000000..2b63294f3789
--- /dev/null
+++ b/llvm/lib/Support/BlockFrequency.cpp
@@ -0,0 +1,82 @@
+//====--------------- lib/Support/BlockFrequency.cpp -----------*- C++ -*-====//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements Block Frequency class.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Support/BlockFrequency.h"
+#include <cassert>
+
+using namespace llvm;
+
+BlockFrequency &BlockFrequency::operator*=(BranchProbability Prob) {
+  Frequency = Prob.scale(Frequency);
+  return *this;
+}
+
+BlockFrequency BlockFrequency::operator*(BranchProbability Prob) const {
+  BlockFrequency Freq(Frequency);
+  Freq *= Prob;
+  return Freq;
+}
+
+BlockFrequency &BlockFrequency::operator/=(BranchProbability Prob) {
+  Frequency = Prob.scaleByInverse(Frequency);
+  return *this;
+}
+
+BlockFrequency BlockFrequency::operator/(BranchProbability Prob) const {
+  BlockFrequency Freq(Frequency);
+  Freq /= Prob;
+  return Freq;
+}
+
+BlockFrequency &BlockFrequency::operator+=(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;
+}
+
+BlockFrequency BlockFrequency::operator+(BlockFrequency Freq) const {
+  BlockFrequency NewFreq(Frequency);
+  NewFreq += Freq;
+  return NewFreq;
+}
+
+BlockFrequency &BlockFrequency::operator-=(BlockFrequency Freq) {
+  // If underflow, set frequency to 0.
+  if (Frequency <= Freq.Frequency)
+    Frequency = 0;
+  else
+    Frequency -= Freq.Frequency;
+  return *this;
+}
+
+BlockFrequency BlockFrequency::operator-(BlockFrequency Freq) const {
+  BlockFrequency NewFreq(Frequency);
+  NewFreq -= Freq;
+  return NewFreq;
+}
+
+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;
+}