[PATCH] D27990: [Thumb] Add support for tMUL in the compare instruction peephole optimizer

[Diana Picus via Phabricator via llvm-commits]

rovka added a comment.

Hi Sjoerd,

I'm not sure this is the best way to go, it looks a bit hacky. Why are we generating MOVS for those constants in the first place? It feels like MOV should do the job just as well, and wouldn't touch the flags.

Cheers,
Diana



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Comment at: test/CodeGen/ARM/mul-cmp-peephole.ll:1
+; RUN: llc < %s -mtriple=thumb-none-eabi | FileCheck %s
+
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I think this would work better as a .mir test (use -stop-before=peephole-opt).


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Comment at: test/CodeGen/ARM/mul-cmp-peephole.ll:28
+  %0 = load i32, i32* %a.addr, align 4
+  %1 = load i32, i32* %b.addr, align 4
+  %mul1 = mul nsw i32 %0, %1
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Is all this alloca clutter relevant to the test?


https://reviews.llvm.org/D27990