[llvm] [RISCV] Fold vector shift of sext/zext to widening multiply (PR #121563)

[Piotr Fusik via llvm-commits]

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@@ -432,19 +432,35 @@ define <8 x i32> @vwsll_vx_i8_v8i32_zext(<8 x i16> %a, i8 %b) {
 }
 
 define <8 x i32> @vwsll_vi_v8i32(<8 x i16> %a) {
-; CHECK-LABEL: vwsll_vi_v8i32:
-; CHECK:       # %bb.0:
-; CHECK-NEXT:    vsetivli zero, 8, e32, m2, ta, ma
-; CHECK-NEXT:    vzext.vf2 v10, v8
-; CHECK-NEXT:    vsll.vi v8, v10, 2
-; CHECK-NEXT:    ret
+; RV32-LABEL: vwsll_vi_v8i32:
+; RV32:       # %bb.0:
+; RV32-NEXT:    vsetivli zero, 8, e32, m2, ta, ma
+; RV32-NEXT:    vzext.vf2 v10, v8
+; RV32-NEXT:    vsll.vi v8, v10, 2
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pfusik wrote:

Fixed by handling VSEXT_VL/VZEXT_VL.

https://github.com/llvm/llvm-project/pull/121563