x86: Transform to "pushq $-1; popq reg" for -Oz

x86: Transform to "pushq $-1; popq reg" for -Oz

commit 4c80062d7b8c272e2e193b8074a8440dbb4fe588
Author: H.J. Lu <hjl.tools@gmail.com>
Date:   Sun May 25 07:40:29 2025 +0800

    x86: Enable *mov<mode>_(and|or) only for -Oz

disabled transformation from "movq $-1,reg" to "pushq $-1; popq reg" for
-Oz.  But for legacy integer registers, the former is 4 bytes and the
latter is 3 bytes.  Enable such transformation for -Oz.

gcc/

	PR target/120427
	* config/i386/i386.md (peephole2): Transform "movq $-1,reg" to
	"pushq $-1; popq reg" for -Oz if reg is a legacy integer register.

gcc/testsuite/

	PR target/120427
	* gcc.target/i386/pr120427-5.c: New test.

Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
(cherry picked from commit 71dae74158d05b75e367629ce21da3f0a2945576)