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/expr.h | 21 ++++++++++++--------- 1 file changed, 12 insertions(+), 9 deletions(-) (limited to 'gcc/expr.h') diff --git a/gcc/expr.h b/gcc/expr.h index fea69a2..bd0da5e 100644 --- a/gcc/expr.h +++ b/gcc/expr.h @@ -103,12 +103,16 @@ enum block_op_methods BLOCK_OP_TAILCALL }; +typedef rtx (*by_pieces_constfn) (void *, HOST_WIDE_INT, machine_mode); + extern rtx emit_block_move (rtx, rtx, rtx, enum block_op_methods); extern rtx emit_block_move_hints (rtx, rtx, rtx, enum block_op_methods, unsigned int, HOST_WIDE_INT, unsigned HOST_WIDE_INT, unsigned HOST_WIDE_INT, unsigned HOST_WIDE_INT); +extern rtx emit_block_cmp_hints (rtx, rtx, rtx, tree, rtx, bool, + by_pieces_constfn, void *); extern bool emit_storent_insn (rtx to, rtx from); /* Copy all or part of a value X into registers starting at REGNO. @@ -173,6 +177,11 @@ extern void use_regs (rtx *, int, int); /* Mark a PARALLEL as holding a parameter for the next CALL_INSN. */ extern void use_group_regs (rtx *, rtx); +#ifdef GCC_INSN_CODES_H +extern rtx expand_cmpstrn_or_cmpmem (insn_code, rtx, rtx, rtx, tree, rtx, + HOST_WIDE_INT); +#endif + /* Write zeros through the storage of OBJECT. If OBJECT has BLKmode, SIZE is its length in bytes. */ extern rtx clear_storage (rtx, rtx, enum block_op_methods); @@ -191,10 +200,6 @@ extern bool set_storage_via_setmem (rtx, rtx, rtx, unsigned int, unsigned HOST_WIDE_INT, unsigned HOST_WIDE_INT); -extern unsigned HOST_WIDE_INT move_by_pieces_ninsns (unsigned HOST_WIDE_INT, - unsigned int, - unsigned int); - /* Return nonzero if it is desirable to store LEN bytes generated by CONSTFUN with several move instructions by store_by_pieces function. CONSTFUNDATA is a pointer which will be passed as argument @@ -203,8 +208,7 @@ extern unsigned HOST_WIDE_INT move_by_pieces_ninsns (unsigned HOST_WIDE_INT, MEMSETP is true if this is a real memset/bzero, not a copy of a const string. */ extern int can_store_by_pieces (unsigned HOST_WIDE_INT, - rtx (*) (void *, HOST_WIDE_INT, - machine_mode), + by_pieces_constfn, void *, unsigned int, bool); /* Generate several move instructions to store LEN bytes generated by @@ -213,8 +217,7 @@ extern int can_store_by_pieces (unsigned HOST_WIDE_INT, ALIGN is maximum alignment we can assume. MEMSETP is true if this is a real memset/bzero, not a copy. Returns TO + LEN. */ -extern rtx store_by_pieces (rtx, unsigned HOST_WIDE_INT, - rtx (*) (void *, HOST_WIDE_INT, machine_mode), +extern rtx store_by_pieces (rtx, unsigned HOST_WIDE_INT, by_pieces_constfn, void *, unsigned int, bool, int); /* Emit insns to set X from Y. */ @@ -295,7 +298,7 @@ rtx get_personality_function (tree); /* Determine whether the LEN bytes can be moved by using several move instructions. Return nonzero if a call to move_by_pieces should succeed. */ -extern int can_move_by_pieces (unsigned HOST_WIDE_INT, unsigned int); +extern bool can_move_by_pieces (unsigned HOST_WIDE_INT, unsigned int); extern unsigned HOST_WIDE_INT highest_pow2_factor (const_tree); -- cgit v1.1