From 36b85e432865a312aa8edc8978e38266e8a0f14c Mon Sep 17 00:00:00 2001 From: Bernd Schmidt Date: Fri, 3 Jun 2016 14:20:53 +0000 Subject: re PR tree-optimization/52171 (memcmp/strcmp/strncmp can be optimized when the result is tested for [in]equality with 0) PR tree-optimization/52171 * builtins.c (expand_cmpstrn_or_cmpmem): Delete, moved elsewhere. (expand_builtin_memcmp): New arg RESULT_EQ. All callers changed. Look for constant strings. Move some code to emit_block_cmp_hints and use it. * builtins.def (BUILT_IN_MEMCMP_EQ): New. * defaults.h (COMPARE_MAX_PIECES): New macro. * expr.c (move_by_pieces_d, store_by_pieces_d): Remove old structs. (move_by_pieces_1, store_by_pieces_1, store_by_pieces_2): Remvoe. (clear_by_pieces_1): Don't declare. Move definition before use. (can_do_by_pieces): New static function. (can_move_by_pieces): Use it. Return bool. (by_pieces_ninsns): Renamed from move_by_pieces_ninsns. New arg OP. All callers changed. Handle COMPARE_BY_PIECES. (class pieces_addr); New. (pieces_addr::pieces_addr, pieces_addr::decide_autoinc, pieces_addr::adjust, pieces_addr::increment_address, pieces_addr::maybe_predec, pieces_addr::maybe_postinc): New member functions for it. (class op_by_pieces_d): New. (op_by_pieces_d::op_by_pieces_d, op_by_pieces_d::run): New member functions for it. (class move_by_pieces_d, class compare_by_pieces_d, class store_by_pieces_d): New subclasses of op_by_pieces_d. (move_by_pieces_d::prepare_mode, move_by_pieces_d::generate, move_by_pieces_d::finish_endp, store_by_pieces_d::prepare_mode, store_by_pieces_d::generate, store_by_pieces_d::finish_endp, compare_by_pieces_d::generate, compare_by_pieces_d::prepare_mode, compare_by_pieces_d::finish_mode): New member functions. (compare_by_pieces, emit_block_cmp_via_cmpmem): New static functions. (expand_cmpstrn_or_cmpmem): Moved here from builtins.c. (emit_block_cmp_hints): New function. (move_by_pieces, store_by_pieces, clear_by_pieces): Rewrite to just use the newly defined classes. * expr.h (by_pieces_constfn): New typedef. (can_store_by_pieces, store_by_pieces): Use it in arg declarations. (emit_block_cmp_hints, expand_cmpstrn_or_cmpmem): Declare. (move_by_pieces_ninsns): Don't declare. (can_move_by_pieces): Change return value to bool. * target.def (TARGET_USE_BY_PIECES_INFRASTRUCTURE_P): Update docs. (compare_by_pieces_branch_ratio): New hook. * target.h (enum by_pieces_operation): Add COMPARE_BY_PIECES. (by_pieces_ninsns): Declare. * targethooks.c (default_use_by_pieces_infrastructure_p): Handle COMPARE_BY_PIECES. (default_compare_by_pieces_branch_ratio): New function. * targhooks.h (default_compare_by_pieces_branch_ratio): Declare. * doc/tm.texi.in (STORE_MAX_PIECES, COMPARE_MAX_PIECES): Document. * doc/tm.texi: Regenerate. * tree-ssa-strlen.c: Include "builtins.h". (handle_builtin_memcmp): New static function. (strlen_optimize_stmt): Call it for BUILT_IN_MEMCMP. * tree.c (build_common_builtin_nodes): Create __builtin_memcmp_eq. testsuite/ PR tree-optimization/52171 * gcc.dg/pr52171.c: New test. * gcc.target/i386/pr52171.c: New test. From-SVN: r237069 --- gcc/target.h | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) (limited to 'gcc/target.h') diff --git a/gcc/target.h b/gcc/target.h index 43022bd92c3..f4fed68ba32 100644 --- a/gcc/target.h +++ b/gcc/target.h @@ -79,16 +79,23 @@ enum print_switch_type }; /* Types of memory operation understood by the "by_pieces" infrastructure. - Used by the TARGET_USE_BY_PIECES_INFRASTRUCTURE_P target hook. */ + Used by the TARGET_USE_BY_PIECES_INFRASTRUCTURE_P target hook and + internally by the functions in expr.c. */ enum by_pieces_operation { CLEAR_BY_PIECES, MOVE_BY_PIECES, SET_BY_PIECES, - STORE_BY_PIECES + STORE_BY_PIECES, + COMPARE_BY_PIECES }; +extern unsigned HOST_WIDE_INT by_pieces_ninsns (unsigned HOST_WIDE_INT, + unsigned int, + unsigned int, + by_pieces_operation); + typedef int (* print_switch_fn_type) (print_switch_type, const char *); /* An example implementation for ELF targets. Defined in varasm.c */ -- cgit v1.2.1