[GlobalISel] Add constant folding support for G_FMA/G_FMAD in the combiner. #65659
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arsenm
reviewed
Sep 7, 2023
| MatchInfo = ConstantFP::get(MI.getMF()->getFunction().getContext(), Op1F); | ||
| break; | ||
| case TargetOpcode::G_FMAD: { | ||
| APFloat Res = (Op1F * Op2F) + Op3F; |
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Should just fold the same as FMA, that's what the IR does for fmuladd. This is also making this host dependent on compiler choice to contract
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Isn't the whole point of having 2 different intrinsics that we have different behaviour?
Also, this isn't host dependent because this is still doing APFloat arithmetic through the operator overloads.
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It's a codegen selected behavior. You may get fma or muladd
arsenm
approved these changes
Sep 9, 2023
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