[llvm] [AArch64][GlobalISel] Add sign bits for G_VASHR (PR #210269)

[Matt Arsenault via llvm-commits]

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@@ -3099,6 +3100,13 @@ unsigned AArch64TargetLowering::computeNumSignBitsForTargetInstr(
     LLT VT = MRI.getType(R);
     return VT.getScalarSizeInBits();
   }
+  case AArch64::G_VASHR: {
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arsenm wrote:

This really ought to have a G_AARCH64_ prefix 

https://github.com/llvm/llvm-project/pull/210269