gh-126612: Reserve an extra word on the stack as scratch space for uops #126613
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UOPs may want to pass values on the stack for consumption by subsequent uops. This works if the generic opcode has a positive stack effect, but may not be possible otherwise. As a simple solution, always reserve space for one extra word on the stack.
mpage
requested review from
ericsnowcurrently,
markshannon and
iritkatriel
as code owners
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uops may want to pass values on the stack for consumption by subsequent uops. This works if the generic opcode has a stack effect greater than the number of values being passed, but may not be possible otherwise.
As a simple compromise, reserve space for one extra word on the stack, ensuring it's always safe to pass a single value.