[llvm] [NVPTX] Improve folding to mad with immediate 1 (PR #93628)

[Artem Belevich via llvm-commits]

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@@ -0,0 +1,101 @@
+; RUN: llc < %s -march=nvptx -mcpu=sm_20 -O1 | FileCheck %s
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Artem-B wrote:

Another test which could use autogenerated CHECK patterns.

https://github.com/llvm/llvm-project/pull/93628