[PATCH] D52416: Allow FP types for atomicrmw xchg

[Matt Arsenault via Phabricator via llvm-commits]

arsenm marked an inline comment as done.
arsenm added inline comments.


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Comment at: lib/CodeGen/SelectionDAG/LegalizeFloatTypes.cpp:2171
+  EVT VT = N->getValueType(0);
+  assert(VT == MVT::f16 && "unhandled case");
+
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jfb wrote:
> I don't get why only FP16 is accessible here.
We don't support any other cases where a narrower FP type is illegal, but a wider one is. That would require a generalized version of FP16_TO_FP/FP_TO_FP16. There aren't any in tree targets that support f64 but not f32 for example.

I've removed this assertion, so this will fail in GetPromotionOpcode for any other type like any other legalization would


https://reviews.llvm.org/D52416