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Re: Canonicalization of compares performed as side-effect operations
On 14/08/2019 08:48, Eric Botcazou wrote:
[Sorry for the delay, I missed your question...]
Interesting. Does it work for the general case of a reverse subtract,
which I need to handle as wel?
Not clear, Visium only uses it for SNE and combined NEG/SNE.
I worked through the logic. I'm pretty sure it will work for any
unsigned or equality comparison and for any constant. The general
(cst uns/eq/op reg) == (~reg uns/eq/op ~cst)