[PATCH] D91962: Add support for STRICT_FSETCC promotion

[Ulrich Weigand via Phabricator via llvm-commits]

uweigand requested changes to this revision.
uweigand added inline comments.
This revision now requires changes to proceed.


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Comment at: llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp:4617
+  case ISD::STRICT_FSETCC: {
     unsigned ExtOp = ISD::FP_EXTEND;
     if (NVT.isInteger()) {
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When expanding a strict FP operation, we need to take care to never emit any non-strict operation.  It looks like the patch as currently written might cause a "FP_EXTEND" to be emitted, which would violate that rule.

We need to emit a STRICT_FP_EXTEND instead (which needs to be properly chained just before the new STRICT_FSETCC node).   Then everything should be OK since the only case where STRICT_FP_EXTEND might raise an exception is if the input is a (signaling) NaN, in which case the original STRICT_FSETCC would also have raised an exception.



Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D91962/new/

https://reviews.llvm.org/D91962