Turn SLOW_UNALIGNED_ACCESS into a target hook

Turn SLOW_UNALIGNED_ACCESS into a target hook

2017-09-12  Richard Sandiford  <richard.sandiford@linaro.org>
	    Alan Hayward  <alan.hayward@arm.com>
	    David Sherwood <david.sherwood@arm.com>

gcc/
	* defaults.h (SLOW_UNALIGNED_ACCESS): Delete.
	* target.def (slow_unaligned_access): New hook.
	* targhooks.h (default_slow_unaligned_access): Declare.
	* targhooks.c (default_slow_unaligned_access): New function.
	* doc/tm.texi.in (SLOW_UNALIGNED_ACCESS): Replace with...
	(TARGET_SLOW_UNALIGNED_ACCESS): ...this.
	* doc/tm.texi: Regenerate.
	* config/alpha/alpha.h (SLOW_UNALIGNED_ACCESS): Delete.
	* config/arm/arm.h (SLOW_UNALIGNED_ACCESS): Delete.
	* config/i386/i386.h (SLOW_UNALIGNED_ACCESS): Delete commented-out
	definition.
	* config/powerpcspe/powerpcspe.h (SLOW_UNALIGNED_ACCESS): Delete.
	* config/powerpcspe/powerpcspe.c (TARGET_SLOW_UNALIGNED_ACCESS):
	Redefine.
	(rs6000_slow_unaligned_access): New function.
	(rs6000_emit_move): Use it instead of SLOW_UNALIGNED_ACCESS.
	(expand_block_compare): Likewise.
	(expand_strn_compare): Likewise.
	(rs6000_rtx_costs): Likewise.
	* config/riscv/riscv.h (SLOW_UNALIGNED_ACCESS): Delete.
	(riscv_slow_unaligned_access): Likewise.
	* config/riscv/riscv.c (riscv_slow_unaligned_access): Rename to...
	(riscv_slow_unaligned_access_p): ...this and make static.
	(riscv_option_override): Update accordingly.
	(riscv_slow_unaligned_access): New function.
	(TARGET_SLOW_UNALIGNED_ACCESS): Redefine.
	* config/rs6000/rs6000.h (SLOW_UNALIGNED_ACCESS): Delete.
	* config/rs6000/rs6000.c (TARGET_SLOW_UNALIGNED_ACCESS): Redefine.
	(rs6000_slow_unaligned_access): New function.
	(rs6000_emit_move): Use it instead of SLOW_UNALIGNED_ACCESS.
	(rs6000_rtx_costs): Likewise.
	* config/rs6000/rs6000-string.c (expand_block_compare)
	(expand_strn_compare): Use targetm.slow_unaligned_access instead
	of SLOW_UNALIGNED_ACCESS.
	* config/tilegx/tilegx.h (SLOW_UNALIGNED_ACCESS): Delete.
	* config/tilepro/tilepro.h (SLOW_UNALIGNED_ACCESS): Delete.
	* calls.c (expand_call): Use targetm.slow_unaligned_access instead
	of SLOW_UNALIGNED_ACCESS.
	* expmed.c (simple_mem_bitfield_p): Likewise.
	* expr.c (alignment_for_piecewise_move): Likewise.
	(emit_group_load_1): Likewise.
	(emit_group_store): Likewise.
	(copy_blkmode_from_reg): Likewise.
	(emit_push_insn): Likewise.
	(expand_assignment): Likewise.
	(store_field): Likewise.
	(expand_expr_real_1): Likewise.
	* gimple-fold.c (gimple_fold_builtin_memory_op): Likewise.
	* lra-constraints.c (simplify_operand_subreg): Likewise.
	* stor-layout.c (bit_field_mode_iterator::next_mode): Likewise.
	* gimple-ssa-store-merging.c: Likewise in block comment at start
	of file.
	* tree-ssa-strlen.c: Include target.h.
	(handle_builtin_memcmp): Use targetm.slow_unaligned_access instead
	of SLOW_UNALIGNED_ACCESS.
	* system.h (SLOW_UNALIGNED_ACCESS): Poison.

Co-Authored-By: Alan Hayward <alan.hayward@arm.com>
Co-Authored-By: David Sherwood <david.sherwood@arm.com>
From-SVN: r252009