Teach ValueTracking about x86 crc32 intrinsics.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@131861 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Analysis/ValueTracking.cpp b/lib/Analysis/ValueTracking.cpp
index 8f18dd278aa08d17979a148fa0cea94ada1b9b70..7b7e39f6c4100243ae2c21e3fa073bc2c1fa3a5e 100644 (file)
--- a/lib/Analysis/ValueTracking.cpp
+++ b/lib/Analysis/ValueTracking.cpp
@@ -670,6 +670,10 @@ void llvm::ComputeMaskedBits(Value *V, const APInt &Mask,
         KnownZero = APInt::getHighBitsSet(BitWidth, BitWidth - LowBits);
         break;
       }
+      case Intrinsic::x86_sse42_crc64_8:
+      case Intrinsic::x86_sse42_crc64_64:
+        KnownZero = APInt::getHighBitsSet(64, 32);
+        break;
       }
     }
     break;