[PATCH] D55992: [ARM] Add missing patterns for DSP muls

[Eli Friedman via Phabricator via llvm-commits]

efriedma added inline comments.


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Comment at: lib/Target/ARM/ARMInstrThumb2.td:2754
+def : Thumb2DSPPat<(mul sext_16_node:$Rm, (sext_inreg rGPR:$Rn, i16)),
+                   (t2SMULBB rGPR:$Rm, rGPR:$Rn)>;
 def : Thumb2DSPPat<(mul sext_16_node:$Rn, (sra rGPR:$Rm, (i32 16))),
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Does ISel automatically match the commuted version?  (IIRC it does, but I haven't looked in a while.)

Could you use "PatFrags" to make a pattern that's either a sext_inreg or a sext_16_node, so you don't have to repeat these patterns?  I haven't actually tried something like that, but I think it's possible.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D55992/new/

https://reviews.llvm.org/D55992