From: Nadav Rotem <nrotem@apple.com>
Date: Sun, 11 Nov 2012 05:34:45 +0000 (+0000)
Subject: Use the isTruncFree and isZExtFree API to figure out of these operations are free... 
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=3b99dc62a75c88178ad2a96e96f3f1efb992e59f;p=platform%2Fupstream%2Fllvm.git

Use the isTruncFree and isZExtFree API to figure out of these operations are free. Thanks Andy!

llvm-svn: 167685
---

diff --git a/llvm/lib/Target/TargetTransformImpl.cpp b/llvm/lib/Target/TargetTransformImpl.cpp
index c07332d..b36e6f8 100644
--- a/llvm/lib/Target/TargetTransformImpl.cpp
+++ b/llvm/lib/Target/TargetTransformImpl.cpp
@@ -214,8 +214,16 @@ unsigned VectorTargetTransformImpl::getCastInstrCost(unsigned Opcode, Type *Dst,
   // Handle scalar conversions.
   if (!Src->isVectorTy() && !Dst->isVectorTy()) {
 
-    // Scalar bitcasts and truncs are usually free.
-    if (Opcode == Instruction::BitCast || Opcode == Instruction::Trunc)
+    // Scalar bitcasts are usually free.
+    if (Opcode == Instruction::BitCast)
+      return 0;
+
+    if (Opcode == Instruction::Trunc &&
+        TLI->isTruncateFree(SrcLT.second, DstLT.second))
+      return 0;
+
+    if (Opcode == Instruction::ZExt &&
+        TLI->isZExtFree(SrcLT.second, DstLT.second))
       return 0;
 
     // Just check the op cost. If the operation is legal then assume it costs 1.