[PATCH] D149383: [SelectionDAG][WIP] Add support for evaluating SetCC based on knownbits

[Simon Pilgrim via Phabricator via llvm-commits]

RKSimon requested changes to this revision.
RKSimon added a comment.
This revision now requires changes to proceed.

There's still a lot of tests in here that need adjusting so that they still test what we want them to test



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Comment at: llvm/test/CodeGen/X86/fold-rmw-ops.ll:1372
   store i64 %or, ptr @g64
   %cond = icmp eq i64 %or, 0
   br i1 %cond, label %a, label %b
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goldstein.w.n wrote:
> RKSimon wrote:
> > goldstein.w.n wrote:
> > > RKSimon wrote:
> > > > comparing against zero in all these or-with-imm tests just seems to be a copy+paste from the other logic ops in this file - maybe change it to something that isn't constant foldable (test for -ve?)
> > > re: 'test for -ve?' hmm?
> > > 
> > > But would generally prefer to add new tests than modify existing.
> > 'test for -ve' === 'test for negative'
> > 
> > Adding additional tests would be fine.
> As in add a new test file? This isn't a new file for the series, its just affected by the change.
I'd prefer that these tests were adjusted, the icmp_eq vs 0 was just a dumb copy + paste - but if you don't want to do that, duplicating these OR tests immediately below with a icmp_sgt 0 would be OK


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Comment at: llvm/test/CodeGen/X86/hoist-and-by-const-from-shl-in-eqcmp-zero.ll:801
+; X64-NEXT:    xorl %eax, %eax
 ; X64-NEXT:    retq
   %t0 = shl i8 128, %y
----------------
this needs adjusting


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Comment at: llvm/test/CodeGen/X86/or-with-overflow.ll:6
 ;
 ; PR48768 - 'or' clears the overflow flag, so we don't need a separate 'test'.
 ;
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All these tests need adjusting


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Comment at: llvm/test/CodeGen/X86/pr16031.ll:9
 ; CHECK-NEXT:    xorl %edx, %edx
 ; CHECK-NEXT:    retl
 entry:
----------------
not sure what to do with this test - either we try to fix it so it still matches what the original bug was about, or we delete it


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Comment at: llvm/test/CodeGen/X86/shrink-compare.ll:128
+; CHECK-NEXT:    movb $1, %al
+; CHECK-NEXT:    testb %al, %al
 ; CHECK-NEXT:    je bar # TAILCALL
----------------
This is no longer a shrink-compare test


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D149383/new/

https://reviews.llvm.org/D149383