Made the logical shift / artihmetic shift not rely on signs of intigers #749
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Currently,
ashr&lshrshare the same implementation, and the shift type is guessed based on the sign of the type.This is incorrect W.R.T.
cg_ssasemantics(type don't have signs, operations do), and has caused silent miscompilations in the past(cg_ssarequested a logcal shift, butcg_gccinserted an arithmetic one). This bug was pretty rare, but was still a miscompilation.This PR fixes that bug, by introducing a new parameter(
ShiftKind) togcc_shr(renamed fromgcc_lshr). This allows both shift kinds to still share an implementation, while being very explicit about the requested shift.