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

[Paul Walker 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
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paulwalker-arm wrote:

You can drop `-mtriple=aarch64-linux-gnu` because the IR already contains the triple.

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