Remove global call sets: postreload-gcse.c

Remove global call sets: postreload-gcse.c

This is another case in which we should conservatively treat
partial kills as full kills.

2019-09-30  Richard Sandiford  <richard.sandiford@arm.com>

gcc/
	* postreload-gcse.c: Include regs.h and function-abi.h.
	(record_opr_changes): Use insn_callee_abi to get the ABI of the
	call insn target.  Conservatively assume that partially-clobbered
	registers are altered.

From-SVN: r276329