[llvm] [LLVM][CodeGen][SVE] Add isel for zext(setcc(x,0,ne)) -> umin(x,1). (PR #209452)

[Paul Walker via llvm-commits]

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@@ -89,6 +89,46 @@ define <vscale x 2 x i64> @icmp_cnot_nxv2i64(<vscale x 2 x i64> %a) {
   ret <vscale x 2 x i64> %zext
 }
 
+define <vscale x 16 x i8> @icmp_clamp_i1_nxv16i8(<vscale x 16 x i8> %a) {
+; CHECK-LABEL: icmp_clamp_i1_nxv16i8:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    umin z0.b, z0.b, #1
+; CHECK-NEXT:    ret
+  %mask = icmp ne <vscale x 16 x i8> %a, zeroinitializer
+  %zext = zext <vscale x 16 x i1> %mask to <vscale x 16 x i8>
+  ret <vscale x 16 x i8> %zext
+}
+
+define <vscale x 8 x i16> @icmp_clamp_i1_nxv8i16(<vscale x 8 x i16> %a) {
+; CHECK-LABEL: icmp_clamp_i1_nxv8i16:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    umin z0.h, z0.h, #1
+; CHECK-NEXT:    ret
+  %mask = icmp ne <vscale x 8 x i16> %a, zeroinitializer
+  %zext = zext <vscale x 8 x i1> %mask to <vscale x 8 x i16>
+  ret <vscale x 8 x i16> %zext
+}
+
+define <vscale x 4 x i32> @icmp_clamp_i1_nxv4i32(<vscale x 4 x i32> %a) {
+; CHECK-LABEL: icmp_clamp_i1_nxv4i32:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    umin z0.s, z0.s, #1
+; CHECK-NEXT:    ret
+  %mask = icmp ne <vscale x 4 x i32> %a, zeroinitializer
+  %zext = zext <vscale x 4 x i1> %mask to <vscale x 4 x i32>
+  ret <vscale x 4 x i32> %zext
+}
+
+define <vscale x 2 x i64> @icmp_clamp_i1_nxv2i64(<vscale x 2 x i64> %a) {
+; CHECK-LABEL: icmp_clamp_i1_nxv2i64:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    umin z0.d, z0.d, #1
+; CHECK-NEXT:    ret
+  %mask = icmp ne <vscale x 2 x i64> %a, zeroinitializer
+  %zext = zext <vscale x 2 x i1> %mask to <vscale x 2 x i64>
+  ret <vscale x 2 x i64> %zext
+}
+
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paulwalker-arm wrote:

I don't think so because for regular commutative operations we can/should assume constants will be canonicalised to the RHS.

https://github.com/llvm/llvm-project/pull/209452