[PATCH] D73210: [OPT_DPG][LIVEDEBUGVALUES] Teach Live Debug Values About Meta Instructions

Wed Jan 22 11:37:39 PST 2020

vsk accepted this revision.
vsk added a comment.
This revision is now accepted and ready to land.

LGTM, but please wait for another +1.

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Comment at: llvm/test/DebugInfo/MIR/X86/entry-value-of-modified-param.mir:106
     DBG_VALUE $ebx, $noreg, !17, !DIExpression(), debug-location !20
-    renamable $edi = KILL $edi, implicit-def $rdi
+    $edi = MOV32ri 5, debug-location !22
     DBG_VALUE $edi, $noreg, !16, !DIExpression(), debug-location !20
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TWeaver wrote:
> djtodoro wrote:
> > What is the intention here?
> The KILL was being picked up as a def in the test and was causing a DBG_VALUE instruction to be created. This was tested for in the check list. Ignoring KILL instructions means that livedebugvalues wasn't creating the second entry DBG_VALUE for ARG_A anymore. 
> 
> In order to further preserve what I figured was intended behaviour in the test I changed it to a concrete register def.
> 
> The original entry value patch, SFAIK, had nothing to do with KILL/meta instructions. I figured the KILL instruction was there by coincidence rather than intention.
> 
> happy to reconsider this if that's not the case.
> 
> Cheers
> Tom W
This seems like a reasonable change, we just want a real def here. We could just remove the second CHECK for ARG_A, but that arguably drops code coverage.

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D73210/new/

https://reviews.llvm.org/D73210