[PATCH] D89956: [AArch64] Redundant masks in downcast long multiply

[Dave Green via Phabricator via llvm-commits]

dmgreen added a comment.

Looks nice to me. Is it worth adding mul (sext_inreg, sext i32) patterns too in case one operand is sext and the other is being masked? mul is commutative so I think it would only be two extra patterns, one for sext and one for zext.



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Comment at: llvm/lib/Target/AArch64/AArch64InstrInfo.td:1477
+def : Pat<(mul (sext_inreg GPR64:$Rn, i32), (sext_inreg GPR64:$Rm, i32)),
+         (SMADDLrrr (EXTRACT_SUBREG $Rn, sub_32), (EXTRACT_SUBREG $Rm, sub_32), XZR)>;
+def : Pat<(mul (and GPR64:$Rn, 0xFFFFFFFF), (and GPR64:$Rm, 0xFFFFFFFF)),
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Nit: Can you line up the ('s for the input and the output
The other patterns below have output type's too. It's probably worth adding those just for consistency.


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https://reviews.llvm.org/D89956