https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100694
Roger Sayle <roger at nextmovesoftware dot com> changed:
What |Removed |Added
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CC| |roger at nextmovesoftware dot
com
--- Comment #2 from Roger Sayle <roger at nextmovesoftware dot com> ---
On x86, I proposed tackling this type of poor code generation issue for TImode
operations by introducing a zero_extendditi2 pattern. Currently rs6000.md
(also)
doesn't provide a zero extension operation from DImode to TImode, so the
middle-end expands things using SUBREGs, which unfortunately interferes with
combine's ability to optimize things. Improving x86_64's TImode operations
is still a work in progress, but a patch for issues similar to rs6000.md's was
posted here: https://gcc.gnu.org/pipermail/gcc-patches/2022-June/596165.html
Perhaps similar zero_extend and *concat operations would help on powerpc*?
