Simon Pilgrim ea4ee76d88 [DAG] computeKnownBits - add ISD::MULHS/MULHU/SMUL_LOHI/UMUL_LOHI handling ...

Reuse the existing KnownBits multiplication code to handle the 'extend + multiply + extract high bits' pattern for multiply-high ops.

Noticed while looking at the codegen for D88785 / D98587 - the patch helps division-by-constant expansion code in particular, which suggests that we might have some further KnownBits div/rem cases we could handle - but this was far easier to implement.

Differential Revision: https://reviews.llvm.org/D98857

2021-03-19 16:02:31 +00:00

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Alloc

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Arith

[DAG] computeKnownBits - add ISD::MULHS/MULHU/SMUL_LOHI/UMUL_LOHI handling

2021-03-19 16:02:31 +00:00

CConv

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CodeModel

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Control

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Encoding

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CollapseMOVEM.mir

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lit.local.cfg

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varargs.ll

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