On 9/13/26 1:57 PM, Dominic P wrote:
A - MIN (B, C) -> A + MAX (-B, -C)
A - MAX (B, C) -> A + MIN (-B, -C)
when B and C are negatable. TYPE_OVERFLOW_UNDEFINED is required as well:
for a wrapping type negate_expr_p accepts X - Y, which can be the type
minimum. This catches A - MIN (-x, 5), which min (-A, -B) -> -max (A, B)
does not.
Bootstrapped and regression tested on x86_64-pc-linux-gnu.
Assisted-by: Claude Opus 5 (Anthropic)
gcc/ChangeLog:
* match.pd (A - MIN (B, C), A - MAX (B, C)): New patterns.
gcc/testsuite/ChangeLog:
* gcc.dg/torture/minmax-negate-1.c: New test.
* gcc.dg/tree-ssa/minmax-negate-1.c: New test.
* gcc.dg/tree-ssa/minmax-negate-2.c: New test.
* gcc.dg/tree-ssa/minmax-negate-3.c: New test.
Signed-off-by: Dominic P <[email protected]>
THanks. I've pushed this to the trunk.
ISTM like you ought to go ahead and get commit privs since you're doing
great work and are clearly engaged on improving GCC.
https://gcc.gnu.org/gitwrite.html#authenticated
Should have a link to this form:
https://sourceware.org/cgi-bin/pdw/ps_form.cgi
Fill it out, you can list me as sponsoring your request.
Jeff
