On Fri, Feb 04, 2022 at 02:49:13PM +0100, Richard Biener wrote:
> Any comments? I have mixed feelings with proposing this for GCC 12
> but like to hear from others as well. I didn't try to evaluate
> the quality of stack slot sharing before/after this change besides
> fixing the testsuite fallout (we have a few testcases checking for
> specific instances).
I have mixed feelings too, it is quite risky, on the other side we have
those numerous otherwise unsolvable PRs.
I wonder if tree-ssa-live.cc (compute_live_vars_1) doesn't need similar
changes, after all, it is a variant of the cfgexpand algorithm.
And I'll certainly need to incrementally mark most if not all current
build_clobbers in omp-low.cc as EOLs and emit birth clobbers (stuff that is
added post gimplification, so too late for gimplification's added birth/eol
handling there and so it must be done manually).
Jakub
