R600: Remove unnecessary part of computeKnownBitsForTargetNode

Zero-width BFEs are combined away already, so there's no point in
handling them.

llvm-svn: 219868

diff --git a/llvm/lib/Target/R600/AMDGPUISelLowering.cpp b/llvm/lib/Target/R600/AMDGPUISelLowering.cpp
index b7df3d8..ab771f5 100644 (file)
--- a/llvm/lib/Target/R600/AMDGPUISelLowering.cpp
+++ b/llvm/lib/Target/R600/AMDGPUISelLowering.cpp
@@ -2388,11 +2388,6 @@ void AMDGPUTargetLowering::computeKnownBitsForTargetNode(
 
     unsigned BitWidth = 32;
     uint32_t Width = CWidth->getZExtValue() & 0x1f;
-    if (Width == 0) {
-      KnownZero = APInt::getAllOnesValue(BitWidth);
-      KnownOne = APInt::getNullValue(BitWidth);
-      return;
-    }
 
     // FIXME: This could do a lot more. If offset is 0, should be the same as
     // sign_extend_inreg implementation, but that involves duplicating it.