[llvm] [LLVM][InstCombine] Enable constant folding for SVE asr,lsl and lsr intrinsics. (PR #137350)

[David Sherwood via llvm-commits]

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@@ -6,8 +6,7 @@ target triple = "aarch64-unknown-linux-gnu"
 define <vscale x 16 x i8> @constant_asr_i8_shift_by_0(<vscale x 16 x i1> %pg) #0 {
 ; CHECK-LABEL: define <vscale x 16 x i8> @constant_asr_i8_shift_by_0(
 ; CHECK-SAME: <vscale x 16 x i1> [[PG:%.*]]) #[[ATTR0:[0-9]+]] {
-; CHECK-NEXT:    [[R:%.*]] = call <vscale x 16 x i8> @llvm.aarch64.sve.asr.nxv16i8(<vscale x 16 x i1> [[PG]], <vscale x 16 x i8> splat (i8 7), <vscale x 16 x i8> zeroinitializer)
-; CHECK-NEXT:    ret <vscale x 16 x i8> [[R]]
+; CHECK-NEXT:    ret <vscale x 16 x i8> splat (i8 7)
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david-arm wrote:

I assume it folds to `splat (i8 7)` here because it's merging in `vscale x 16 x i8> splat (i8 7)` so the predicate is irrelevant?

https://github.com/llvm/llvm-project/pull/137350