[clang] [llvm] [SPIRV] add pre legalization instruction combine (PR #122839)

[Vyacheslav Levytskyy via llvm-commits]

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@@ -0,0 +1,140 @@
+; RUN: llc -mtriple=spirv-unknown-unknown -debug-pass=Structure < %s -o /dev/null 2>&1 | \
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VyacheslavLevytskyy wrote:

Just as a thought aloud, I wonder how stable this list can be at this stage of SPIR-V Backend development? I guess this test case may be subjected to more frequent changes than others.
Also I think we'd anyway need to fix -O0 or -Osomething here.

https://github.com/llvm/llvm-project/pull/122839