AArch64: Fold shqri/testl/jcc into cmp/jcc #9660
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We often see patterns like this: shrqi 32, %v0, %v1 testl 0x80000000, %v1 jcc CC_E, ... but really this is the same as asking if %v0 is >= 0. Rewriting this in the form cmp 0, %v0 jcc CC_GE, ... saves two instructions, i.e. a lsr and a mov.
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We often see patterns like this:
shrqi 32, %v0, %v1
testl 0x80000000, %v1
jcc CC_E, ...
but really this is the same as asking if %v0 is >= 0. Rewriting this in the form
cmp 0, %v0
jcc CC_GE, ...
saves two instructions, i.e. a lsr and a mov.