[PATCH] D51542: [X86] Remove wrong ReadAdvance from multiclass sse_fp_unop_s

[Simon Pilgrim via Phabricator via llvm-commits]

RKSimon added a comment.

There seems to be 2 things here - (1) ReadAfterLd is being used incorrectly to try to make a dependency on the dst reg and (2) we have no mechanism to handle partial dependencies like for the scalar sse instructions.

AFAICT this patch fixes the (1) issue but (2) isn't handled at all by the scheduler models yet.



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Comment at: lib/Target/X86/X86InstrSSE.td:2725
                 !strconcat(OpcodeStr, "\t{$src2, $dst|$dst, $src2}"), []>,
                 Sched<[sched.Folded, ReadAfterLd]>;
   }
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Intrinsic version needs updating as well? Although AFAICT this can't be tested within llvm-mca....


https://reviews.llvm.org/D51542