re PR debug/36728 ([stack]: gdb doesn't work with stack alignment)
PR debug/36728
PR debug/55467
PR middle-end/55507
PR bootstrap/55511
* cselib.c (cselib_process_insn): If cselib_preserve_constants,
don't reset table and exit early on volatile insns and setjmp.
Reset table afterwards on setjmp.
* gcc.dg/guality/pr36728-1.c: Include "../nop.h", make sure the asm
are non-empty and add dependency between the first and second asm.
* gcc.dg/guality/pr36728-2.c: Likewise.
* gcc.dg/guality/pr36728-3.c: New test.
* gcc.dg/guality/pr36728-4.c: New test.
From-SVN: r193911