[llvm] fold mov dec/inc to lea +- 1 (PR #185194)

[Simon Pilgrim via llvm-commits]

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@@ -0,0 +1,100 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 6
+; RUN: llc < %s -mtriple=x86_64-unknown-linux-gnu -mattr=+avx2 | FileCheck %s
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RKSimon wrote:

ensure you test -mattr=+slow-3ops-lea / -mattr=-slow-3ops-lea

https://github.com/llvm/llvm-project/pull/185194