[PATCH] D59001: X86TargetLowering::LowerSELECT(): don't promote CMOV's if the subtarget does't have them

[Roman Lebedev via Phabricator via llvm-commits]

lebedev.ri created this revision.
lebedev.ri added reviewers: RKSimon, craig.topper, spatel.
lebedev.ri added a project: LLVM.

I'm not actually sure this patch does the right thing, but then
i'm not sure i understand why we would want to do that promotion
if we don't have CMOV, and thus will expand it to a branch?
Shouldn't some later code be responsible for these decisions?

The real reason for this patch:
I've looked at extending CMOV promotion to support i8, (PR40965 <https://bugs.llvm.org/show_bug.cgi?id=40965>)
and if this check is not in place, `llvm/test/CodeGen/X86/pseudo_cmov_lower.ll` goes real bad.


Repository:
  rL LLVM

https://reviews.llvm.org/D59001

Files:
  lib/Target/X86/X86ISelLowering.cpp
  test/CodeGen/X86/fshl.ll
  test/CodeGen/X86/fshr.ll
  test/CodeGen/X86/midpoint-int.ll
  test/CodeGen/X86/select.ll

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