[LRA]: Don't reuse chosen insn alternative with special memory constraint

[LRA]: Don't reuse chosen insn alternative with special memory constraint

To speed up GCC, LRA reuses chosen alternative from previous
constraint subpass.  A spilled pseudo is considered ok for any memory
constraint although stack slot assigned to the pseudo later might not
satisfy the chosen alternative constraint.  As we don't consider all insn
alternatives on the subsequent LRA sub-passes, it might result in LRA failure
to generate the correct insn.  This patch solves the problem.

gcc/ChangeLog:

	PR target/111225
	* lra-constraints.cc (goal_reuse_alt_p): New global flag.
	(process_alt_operands): Set up the flag.  Clear flag for chosen
	alternative with special memory constraints.
	(process_alt_operands): Set up used insn alternative depending on the flag.

gcc/testsuite/ChangeLog:

	PR target/111225
	* gcc.target/i386/pr111225.c: New test.