[AMDGPU] Remove add/sub combines corrupting carry bit #91
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Isel would apply optimizations in the form of uaddo_carry (add x, y), 0, cc => uaddo_carry x, y, cc. This preserves the correct addition result, but not correct cc bit. For large x and y it could set cc = 0 on the lhs and cc = 1 on the rhs
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@searlmc1 Have you seen this? |
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Isel would apply optimizations in the form of
uaddo_carry (add x, y), 0, cc => uaddo_carry x, y, cc. This preserves the correct addition result, but not correct cc bit. For large x and y it could set cc = 0 on the lhs and cc = 1 on the rhs