[llvm] Fold SVE mul and mul_u to neg during isel (PR #160828)

[Martin Wehking via llvm-commits]

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@@ -0,0 +1,148 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+; RUN: llc -mtriple=aarch64-linux-gnu -verify-machineinstrs -mattr=+sve < %s | FileCheck %s
+
+target triple = "aarch64-unknown-linux-gnu"
+
+; Muls with (-1) as operand should fold to neg.
+define <vscale x 16 x i8> @mul_neg_fold_i8(<vscale x 16 x i1> %pg, <vscale x 16 x i8> %a) {
+; CHECK-LABEL: mul_neg_fold_i8:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    neg z0.b, p0/m, z0.b
+; CHECK-NEXT:    ret
+  %1 = call <vscale x 16 x i8> @llvm.aarch64.sve.dup.x.nxv16i8(i8 -1)
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MartinWehking wrote:

I replaced all of them

https://github.com/llvm/llvm-project/pull/160828