X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FSupport%2FBlockFrequency.cpp;h=e7f3e1764c52d3a6131f022b081227b2f0887f06;hb=b6cb6238b9c5243ec813a860ae153adda1acddff;hp=e0430c199eb86e2b9fec33224d8a1521805598b3;hpb=d4c646110a2d04ce958d373da18507d39aa13564;p=oota-llvm.git

diff --git a/lib/Support/BlockFrequency.cpp b/lib/Support/BlockFrequency.cpp
index e0430c199eb..e7f3e1764c5 100644
--- a/lib/Support/BlockFrequency.cpp
+++ b/lib/Support/BlockFrequency.cpp
@@ -56,6 +56,21 @@ BlockFrequency BlockFrequency::operator+(BlockFrequency Freq) const {
   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);