From e0bd6c9f0aa67d88bbb20019362a4572fc5fac3c Mon Sep 17 00:00:00 2001 From: Richard Sandiford Date: Tue, 12 Sep 2017 13:27:55 +0000 Subject: Turn SLOW_UNALIGNED_ACCESS into a target hook 2017-09-12 Richard Sandiford Alan Hayward David Sherwood 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 Co-Authored-By: David Sherwood From-SVN: r252009 --- gcc/doc/tm.texi | 23 +++++++++++------------ 1 file changed, 11 insertions(+), 12 deletions(-) (limited to 'gcc/doc/tm.texi') diff --git a/gcc/doc/tm.texi b/gcc/doc/tm.texi index c29d249..eb8a618 100644 --- a/gcc/doc/tm.texi +++ b/gcc/doc/tm.texi @@ -6386,23 +6386,22 @@ may eliminate subsequent memory access if subsequent accesses occur to other fields in the same word of the structure, but to different bytes. @end defmac -@defmac SLOW_UNALIGNED_ACCESS (@var{mode}, @var{alignment}) -Define this macro to be the value 1 if memory accesses described by the +@deftypefn {Target Hook} bool TARGET_SLOW_UNALIGNED_ACCESS (machine_mode @var{mode}, unsigned int @var{align}) +This hook returns true if memory accesses described by the @var{mode} and @var{alignment} parameters have a cost many times greater -than aligned accesses, for example if they are emulated in a trap -handler. This macro is invoked only for unaligned accesses, i.e. when +than aligned accesses, for example if they are emulated in a trap handler. +This hook is invoked only for unaligned accesses, i.e. when @code{@var{alignment} < GET_MODE_ALIGNMENT (@var{mode})}. -When this macro is nonzero, the compiler will act as if -@code{STRICT_ALIGNMENT} were nonzero when generating code for block +When this hook returns true, the compiler will act as if +@code{STRICT_ALIGNMENT} were true when generating code for block moves. This can cause significantly more instructions to be produced. -Therefore, do not set this macro nonzero if unaligned accesses only add a -cycle or two to the time for a memory access. +Therefore, do not make this hook return true if unaligned accesses only +add a cycle or two to the time for a memory access. -If the value of this macro is always zero, it need not be defined. If -this macro is defined, it should produce a nonzero value when -@code{STRICT_ALIGNMENT} is nonzero. -@end defmac +The hook must return true whenever @code{STRICT_ALIGNMENT} is true. +The default implementation returns @code{STRICT_ALIGNMENT}. +@end deftypefn @defmac MOVE_RATIO (@var{speed}) The threshold of number of scalar memory-to-memory move insns, @emph{below} -- cgit v1.1