[PATCH] D81918: [PowerPC] Support lowering int-to-fp on ppc_fp128

[Qiu Chaofan via Phabricator via llvm-commits]

qiucf added inline comments.


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Comment at: llvm/lib/CodeGen/SelectionDAG/LegalizeFloatTypes.cpp:1685
   Lo = DAG.getSelectCC(dl, Src, DAG.getConstant(0, dl, SrcVT),
                        Lo, Hi, ISD::SETLT);
   GetPairElements(Lo, Lo, Hi);
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uweigand wrote:
> OK, well, even if we keep the existing algorithm with the FIXME, this still isn't correct as it loses the Chain after the FADD.   I think in the strict case we'll need to use a strict version of SelectCC (passing in the Chain from the FADD) and the use the resulting output Chain for the overall output (via ReplaceValueWith as above -- in fact, if we fall through down here, we actually should *not* do the ReplaceValueWith above, since that would be the wrong chain).
Seems we don't have strict `select_cc`. Here `Src` is integer type, not suitable for `fsetcc+select`?

And yes, I should replace original chain of N with newest chain, both here and inside `isSigned` if block.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D81918/new/

https://reviews.llvm.org/D81918