Phi nodes always use an even number of operands, so don't ever allocate

an odd number.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@129270 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/VMCore/Instructions.cpp b/lib/VMCore/Instructions.cpp
index 33dfcc032af1ac83d5838e7f4d73e6c2dea4ee89..61da9b6b8e0c2b9f6d2698ae1f1f73deaeb7b4e7 100644 (file)
--- a/lib/VMCore/Instructions.cpp
+++ b/lib/VMCore/Instructions.cpp
@@ -137,7 +137,8 @@ Value *PHINode::removeIncomingValue(unsigned Idx, bool DeletePHIIfEmpty) {
 ///
 void PHINode::growOperands() {
   unsigned e = getNumOperands();
-  unsigned NumOps = e*3/2;
+  // Multiply by 1.5 and round down so the result is still even.
+  unsigned NumOps = e + e / 4 * 2;
   if (NumOps < 4) NumOps = 4;      // 4 op PHI nodes are VERY common.
 
   ReservedSpace = NumOps;