From: Kyrylo Tkachov Date: Tue, 30 Jun 2026 12:04:02 +0000 (+0200) Subject: Remove the path-splitting pass and deprecate -fsplit-paths [PR120892] X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=5c23bb074af23f00dd3fe1745b9dd99245fa4bba;p=thirdparty%2Fgcc.git Remove the path-splitting pass and deprecate -fsplit-paths [PR120892] pass_split_paths duplicates the join block of an IF-THEN-ELSE that feeds a loop latch, splitting the two paths to the backedge. It runs only at -O3. In practice it interacts badly with later optimizations: it duplicates the loop body before loads have been commoned and before if-conversion runs, so it can block both loop unrolling (PR120892) and if-conversion of the duplicated diamond, while its own heuristic already declines about half of all candidate blocks, most often to avoid spoiling if-conversion. Remove the pass and deprecate the -fsplit-paths option. The option is kept accepted for backward compatibility via the Ignore flag and now does nothing, matching how other optimization options have been retired (for example -ftree-lrs). param_max_jump_thread_duplication_stmts is retained as it is shared with the jump-threading passes. Statistics from the pass on SPEC CPU 2026 (intrate + fprate, counted from the split-paths dump): candidates splits declined to protect if-conversion -O3 122894 62050 60844 37166 -O3 -flto=auto 52423 21257 31166 21822 The pass splits about half of the blocks it considers and declines the rest, most often to avoid spoiling if-conversion. The duplication grows .text by 0.32% at -O3 and 0.24% at -O3 -flto=auto. Andrea and Jeff indicated in PR120892 that removing -fsplit-paths may be the way to go there. -fsplit-paths also complicates the control-flow and defeats the load-commoning necessary to get good if-conversion of the hot loop from Snappy from https://gcc.gnu.org/bugzilla/show_bug.cgi?id=125557#c13 . Bootstrapped and tested on aarch64-none-linux-gnu and x86_64-linux. gcc/ChangeLog: PR tree-optimization/120892 * gimple-ssa-split-paths.cc: Remove. * passes.def (pass_split_paths): Remove. * tree-pass.h (make_pass_split_paths): Remove. * Makefile.in (OBJS): Remove gimple-ssa-split-paths.o. * timevar.def (TV_SPLIT_PATHS): Remove. * opts.cc (default_options_table): Remove the OPT_LEVELS_3_PLUS entry for OPT_fsplit_paths. * common.opt (fsplit-paths): Make it a deprecated no-op using Ignore. * doc/invoke.texi (-fsplit-paths): Document as deprecated and remove it from the option summary and the -O3 list. gcc/testsuite/ChangeLog: PR tree-optimization/120892 * gcc.dg/tree-ssa/split-path-1.c: Move to... * gcc.c-torture/execute/split-path-1.c: ...here. Adjust to a plain compile and run test without the split-paths dump scan. * gcc.dg/tree-ssa/split-path-2.c: Move to... * gcc.c-torture/compile/split-path-2.c: ...here. Adjust to a compile-only test without the split-paths dump scan. * gcc.dg/tree-ssa/split-path-3.c: Move to... * gcc.c-torture/compile/split-path-3.c: ...here. Likewise. * gcc.dg/tree-ssa/split-path-4.c: Move to... * gcc.c-torture/compile/split-path-4.c: ...here. Likewise. * gcc.dg/tree-ssa/split-path-5.c: Move to... * gcc.c-torture/compile/split-path-5.c: ...here. Likewise. * gcc.dg/tree-ssa/split-path-6.c: Move to... * gcc.c-torture/compile/split-path-6.c: ...here. Likewise. * gcc.dg/tree-ssa/split-path-7.c: Move to... * gcc.c-torture/compile/split-path-7.c: ...here. Likewise. * gcc.dg/tree-ssa/split-path-8.c: Move to... * gcc.c-torture/compile/split-path-8.c: ...here. Likewise. * gcc.dg/tree-ssa/split-path-9.c: Move to... * gcc.c-torture/compile/split-path-9.c: ...here. Likewise. * gcc.dg/tree-ssa/split-path-10.c: Move to... * gcc.c-torture/compile/split-path-10.c: ...here. Likewise. * gcc.dg/tree-ssa/split-path-11.c: Move to... * gcc.c-torture/compile/split-path-11.c: ...here. Likewise. * gcc.dg/tree-ssa/split-path-12.c: Move to... * gcc.c-torture/compile/split-path-12.c: ...here. Likewise. * gcc.dg/tree-ssa/split-path-13.c: Move to... * gcc.c-torture/compile/split-path-13.c: ...here. Likewise. * gcc.dg/tree-ssa/pr69270.c: Move to... * gcc.c-torture/compile/pr69270.c: ...here. Likewise. * g++.dg/tree-ssa/pr88797.C: Move to... * g++.dg/torture/pr88797.C: ...here. Adjust to a compile-only test. * gcc.target/i386/pr106450.c: Remove -fsplit-paths from dg-options. Signed-off-by: Kyrylo Tkachov --- diff --git a/gcc/Makefile.in b/gcc/Makefile.in index 536e2faaaf88..06e711094efd 100644 --- a/gcc/Makefile.in +++ b/gcc/Makefile.in @@ -1542,7 +1542,6 @@ OBJS = \ gimple-ssa-isolate-paths.o \ gimple-ssa-nonnull-compare.o \ gimple-ssa-sccopy.o \ - gimple-ssa-split-paths.o \ gimple-ssa-store-merging.o \ gimple-ssa-strength-reduction.o \ gimple-ssa-sprintf.o \ diff --git a/gcc/common.opt b/gcc/common.opt index 218dddf5dfe9..0055578ccf60 100644 --- a/gcc/common.opt +++ b/gcc/common.opt @@ -3388,8 +3388,8 @@ Common Var(flag_tree_vrp) Init(0) Optimization Perform Value Range Propagation on trees. fsplit-paths -Common Var(flag_split_paths) Init(0) Optimization -Split paths leading to loop backedges. +Common Ignore +Does nothing. Preserved for backward compatibility. funconstrained-commons Common Var(flag_unconstrained_commons) Optimization diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi index 208625cafc55..455ea08d7c73 100644 --- a/gcc/doc/invoke.texi +++ b/gcc/doc/invoke.texi @@ -676,7 +676,7 @@ Objective-C and Objective-C++ Dialects}. -fsemantic-interposition -fshrink-wrap -fshrink-wrap-separate -fsignaling-nans -fsingle-precision-constant -fsplit-ivs-in-unroller -fsplit-loops --fspeculatively-call-stored-functions -fsplit-paths +-fspeculatively-call-stored-functions -fsplit-wide-types -fsplit-wide-types-early -fssa-backprop -fssa-phiopt -fstdarg-opt -fstore-merging -fstrict-aliasing -fipa-strict-aliasing -fthread-jumps -ftracer -ftree-bit-ccp @@ -13626,7 +13626,6 @@ by @option{-O2} and also turns on the following optimization flags: -fpeel-loops -fpredictive-commoning -fsplit-loops --fsplit-paths -ftree-loop-distribution -ftree-partial-pre -funswitch-loops @@ -15469,9 +15468,8 @@ enabled. @opindex fsplit-paths @opindex fno-split-paths @item -fsplit-paths -Split paths leading to loop backedges. This can improve dead code -elimination and common subexpression elimination. This is enabled by -default at @option{-O3} and above. +This option is deprecated and does nothing. It is accepted only for +backward compatibility. @opindex fsplit-ivs-in-unroller @opindex fno-split-ivs-in-unroller diff --git a/gcc/gimple-ssa-split-paths.cc b/gcc/gimple-ssa-split-paths.cc deleted file mode 100644 index 171a581e8f8c..000000000000 --- a/gcc/gimple-ssa-split-paths.cc +++ /dev/null @@ -1,545 +0,0 @@ -/* Support routines for Splitting Paths to loop backedges - Copyright (C) 2015-2026 Free Software Foundation, Inc. - Contributed by Ajit Kumar Agarwal . - - This file is part of GCC. - - GCC is free software; you can redistribute it and/or modify - it under the terms of the GNU General Public License as published by - the Free Software Foundation; either version 3, or (at your option) - any later version. - -GCC is distributed in the hope that it will be useful, -but WITHOUT ANY WARRANTY; without even the implied warranty of -MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the -GNU General Public License for more details. - -You should have received a copy of the GNU General Public License -along with GCC; see the file COPYING3. If not see -. */ - -#include "config.h" -#include "system.h" -#include "coretypes.h" -#include "backend.h" -#include "tree.h" -#include "gimple.h" -#include "tree-pass.h" -#include "tree-cfg.h" -#include "cfganal.h" -#include "cfgloop.h" -#include "gimple-iterator.h" -#include "tracer.h" -#include "predict.h" -#include "gimple-ssa.h" -#include "tree-phinodes.h" -#include "ssa-iterators.h" -#include "fold-const.h" -#include "cfghooks.h" - -/* Given LATCH, the latch block in a loop, see if the shape of the - path reaching LATCH is suitable for being split by duplication. - If so, return the block that will be duplicated into its predecessor - paths. Else return NULL. */ - -static basic_block -find_block_to_duplicate_for_splitting_paths (basic_block latch) -{ - /* We should have simple latches at this point. So the latch should - have a single successor. This implies the predecessor of the latch - likely has the loop exit. And it's that predecessor we're most - interested in. To keep things simple, we're going to require that - the latch have a single predecessor too. */ - if (single_succ_p (latch) && single_pred_p (latch)) - { - basic_block bb = get_immediate_dominator (CDI_DOMINATORS, latch); - gcc_assert (single_pred_edge (latch)->src == bb); - - /* If BB has been marked as not to be duplicated, then honor that - request. */ - if (ignore_bb_p (bb)) - return NULL; - - gimple *last = gsi_stmt (gsi_last_nondebug_bb (bb)); - /* The immediate dominator of the latch must end in a conditional. */ - if (!last || gimple_code (last) != GIMPLE_COND) - return NULL; - - /* We're hoping that BB is a join point for an IF-THEN-ELSE diamond - region. Verify that it is. - - First, verify that BB has two predecessors (each arm of the - IF-THEN-ELSE) and two successors (the latch and exit) and that - all edges are normal. */ - if (EDGE_COUNT (bb->preds) == 2 - && !(EDGE_PRED (bb, 0)->flags & EDGE_COMPLEX) - && !(EDGE_PRED (bb, 1)->flags & EDGE_COMPLEX) - && EDGE_COUNT (bb->succs) == 2 - && !(EDGE_SUCC (bb, 0)->flags & EDGE_COMPLEX) - && !(EDGE_SUCC (bb, 1)->flags & EDGE_COMPLEX)) - { - /* Now verify that BB's immediate dominator ends in a - conditional as well. */ - basic_block bb_idom = get_immediate_dominator (CDI_DOMINATORS, bb); - gimple *last = gsi_stmt (gsi_last_nondebug_bb (bb_idom)); - if (!last || gimple_code (last) != GIMPLE_COND) - return NULL; - - /* And that BB's immediate dominator's successors are the - predecessors of BB or BB itself. */ - if (!(EDGE_PRED (bb, 0)->src == bb_idom - || find_edge (bb_idom, EDGE_PRED (bb, 0)->src)) - || !(EDGE_PRED (bb, 1)->src == bb_idom - || find_edge (bb_idom, EDGE_PRED (bb, 1)->src))) - return NULL; - - /* And that the predecessors of BB each have a single successor - or are BB's immediate domiator itself. */ - if (!(EDGE_PRED (bb, 0)->src == bb_idom - || single_succ_p (EDGE_PRED (bb, 0)->src)) - || !(EDGE_PRED (bb, 1)->src == bb_idom - || single_succ_p (EDGE_PRED (bb, 1)->src))) - return NULL; - - /* So at this point we have a simple diamond for an IF-THEN-ELSE - construct starting at BB_IDOM, with a join point at BB. BB - pass control outside the loop or to the loop latch. - - We're going to want to create two duplicates of BB, one for - each successor of BB_IDOM. */ - return bb; - } - } - return NULL; -} - -/* Return the number of non-debug statements in a block. */ -static unsigned int -count_stmts_in_block (basic_block bb) -{ - gimple_stmt_iterator gsi; - unsigned int num_stmts = 0; - - for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi)) - { - gimple *stmt = gsi_stmt (gsi); - if (!is_gimple_debug (stmt)) - num_stmts++; - } - return num_stmts; -} - -/* Return TRUE if CODE represents a tree code that is not likely to - be easily if-convertible because it likely expands into multiple - insns, FALSE otherwise. */ -static bool -poor_ifcvt_candidate_code (enum tree_code code) -{ - return (code == MIN_EXPR - || code == MAX_EXPR - || code == ABS_EXPR - || code == COND_EXPR); -} - -/* Return TRUE if PRED of BB is an poor ifcvt candidate. */ -static bool -poor_ifcvt_pred (basic_block pred, basic_block bb) -{ - /* If the edge count of the pred is not 1, then - this is the predecessor from the if rather - than middle one. */ - if (EDGE_COUNT (pred->succs) != 1) - return false; - - /* Empty middle bb are never a poor ifcvt candidate. */ - if (empty_block_p (pred)) - return false; - /* If BB's predecessors are single statement blocks where - the output of that statement feed the same PHI in BB, - it an ifcvt candidate. */ - gimple *stmt = last_and_only_stmt (pred); - if (!stmt || gimple_code (stmt) != GIMPLE_ASSIGN) - return true; - - /* If the statement could trap, then this is a poor ifcvt candidate. */ - if (gimple_could_trap_p (stmt)) - return true; - - tree_code code = gimple_assign_rhs_code (stmt); - if (poor_ifcvt_candidate_code (code)) - return true; - tree lhs = gimple_assign_lhs (stmt); - gimple_stmt_iterator gsi; - for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi)) - { - gimple *phi = gsi_stmt (gsi); - if (gimple_phi_arg_def (phi, 0) == lhs - || gimple_phi_arg_def (phi, 1) == lhs) - return false; - } - return true; -} - -/* Return TRUE if BB is a reasonable block to duplicate by examining - its size, false otherwise. BB will always be a loop latch block. - - Things to consider: - - We do not want to spoil if-conversion if at all possible. - - Most of the benefit seems to be from eliminating the unconditional - jump rather than CSE/DCE opportunities. So favor duplicating - small latches. A latch with just a conditional branch is ideal. - - CSE/DCE opportunities crop up when statements from the predecessors - feed statements in the latch and allow statements in the latch to - simplify. */ - -static bool -is_feasible_trace (basic_block bb) -{ - basic_block pred1 = EDGE_PRED (bb, 0)->src; - basic_block pred2 = EDGE_PRED (bb, 1)->src; - int num_stmts_in_join = count_stmts_in_block (bb); - int num_stmts_in_pred1 - = EDGE_COUNT (pred1->succs) == 1 ? count_stmts_in_block (pred1) : 0; - int num_stmts_in_pred2 - = EDGE_COUNT (pred2->succs) == 1 ? count_stmts_in_block (pred2) : 0; - - /* Upper Hard limit on the number statements to copy. */ - if (num_stmts_in_join - >= param_max_jump_thread_duplication_stmts) - { - if (dump_file && (dump_flags & TDF_DETAILS)) - fprintf (dump_file, - "Duplicating block %d would duplicate " - "too many statements: %d >= %d\n", - bb->index, num_stmts_in_join, - param_max_jump_thread_duplication_stmts); - return false; - } - - /* This is meant to catch cases that are likely opportunities for - if-conversion. */ - if (num_stmts_in_pred1 <= 1 && num_stmts_in_pred2 <= 1) - { - int num_phis = 0; - /* The max number of PHIs that should be considered for an ifcvt - candidate. */ - const int max_num_phis = 3; - for (gphi_iterator si = gsi_start_phis (bb); ! gsi_end_p (si); - gsi_next (&si)) - { - num_phis++; - if (num_phis > max_num_phis) - break; - } - if (num_phis <= max_num_phis - && !poor_ifcvt_pred (pred1, bb) - && !poor_ifcvt_pred (pred2, bb)) - { - if (dump_file && (dump_flags & TDF_DETAILS)) - fprintf (dump_file, - "Block %d appears to be a join point for " - "if-convertible bbs.\n", - bb->index); - return false; - } - } - - /* If the joiner has no PHIs with useful uses there is zero chance - of CSE/DCE/jump-threading possibilities exposed by duplicating it. */ - bool found_useful_phi = false; - for (gphi_iterator si = gsi_start_phis (bb); ! gsi_end_p (si); - gsi_next (&si)) - { - gphi *phi = si.phi (); - use_operand_p use_p; - imm_use_iterator iter; - FOR_EACH_IMM_USE_FAST (use_p, iter, gimple_phi_result (phi)) - { - gimple *stmt = USE_STMT (use_p); - if (is_gimple_debug (stmt)) - continue; - /* If there's a use in the joiner this might be a CSE/DCE - opportunity, but not if the use is in a conditional - which makes this a likely if-conversion candidate. */ - if (gimple_bb (stmt) == bb - && (!is_gimple_assign (stmt) - || (TREE_CODE_CLASS (gimple_assign_rhs_code (stmt)) - != tcc_comparison))) - { - found_useful_phi = true; - break; - } - /* If the use is on a loop header PHI and on one path the - value is unchanged this might expose a jump threading - opportunity. */ - if (gimple_code (stmt) == GIMPLE_PHI - && gimple_bb (stmt) == bb->loop_father->header - /* But for memory the PHI alone isn't good enough. */ - && ! virtual_operand_p (gimple_phi_result (stmt))) - { - bool found_unchanged_path = false; - for (unsigned i = 0; i < gimple_phi_num_args (phi); ++i) - if (gimple_phi_arg_def (phi, i) == gimple_phi_result (stmt)) - { - found_unchanged_path = true; - break; - } - /* If we found an unchanged path this can only be a threading - opportunity if we have uses of the loop header PHI result - in a stmt dominating the merge block. Otherwise the - splitting may prevent if-conversion. */ - if (found_unchanged_path) - { - use_operand_p use2_p; - imm_use_iterator iter2; - FOR_EACH_IMM_USE_FAST (use2_p, iter2, gimple_phi_result (stmt)) - { - gimple *use_stmt = USE_STMT (use2_p); - if (is_gimple_debug (use_stmt)) - continue; - basic_block use_bb = gimple_bb (use_stmt); - if (use_bb != bb - && dominated_by_p (CDI_DOMINATORS, bb, use_bb)) - { - if (gcond *cond = dyn_cast (use_stmt)) - if (gimple_cond_code (cond) == EQ_EXPR - || gimple_cond_code (cond) == NE_EXPR) - found_useful_phi = true; - break; - } - } - } - if (found_useful_phi) - break; - } - } - if (found_useful_phi) - break; - } - /* There is one exception namely a controlling condition we can propagate - an equivalence from to the joiner. */ - bool found_cprop_opportunity = false; - basic_block dom = get_immediate_dominator (CDI_DOMINATORS, bb); - gcond *cond = as_a (*gsi_last_bb (dom)); - if (gimple_cond_code (cond) == EQ_EXPR - || gimple_cond_code (cond) == NE_EXPR) - for (unsigned i = 0; i < 2; ++i) - { - tree op = gimple_op (cond, i); - if (TREE_CODE (op) == SSA_NAME) - { - use_operand_p use_p; - imm_use_iterator iter; - FOR_EACH_IMM_USE_FAST (use_p, iter, op) - { - if (is_gimple_debug (USE_STMT (use_p))) - continue; - if (gimple_bb (USE_STMT (use_p)) == bb) - { - found_cprop_opportunity = true; - break; - } - } - } - if (found_cprop_opportunity) - break; - } - - if (! found_useful_phi && ! found_cprop_opportunity) - { - if (dump_file && (dump_flags & TDF_DETAILS)) - fprintf (dump_file, - "Block %d is a join that does not expose CSE/DCE/jump-thread " - "opportunities when duplicated.\n", - bb->index); - return false; - } - - /* We may want something here which looks at dataflow and tries - to guess if duplication of BB is likely to result in simplification - of instructions in BB in either the original or the duplicate. */ - return true; -} - -/* If the immediate dominator of the latch of the loop is - block with conditional branch, then the loop latch is - duplicated to its predecessors path preserving the SSA - semantics. - - CFG before transformation. - - 2 - | - | - +---->3 - | / \ - | / \ - | 4 5 - | \ / - | \ / - | 6 - | / \ - | / \ - | 8 7 - | | | - ---+ E - - - - Block 8 is the latch. We're going to make copies of block 6 (9 & 10) - and wire things up so they look like this: - - 2 - | - | - +---->3 - | / \ - | / \ - | 4 5 - | | | - | | | - | 9 10 - | |\ /| - | | \ / | - | | 7 | - | | | | - | | E | - | | | - | \ / - | \ / - +-----8 - - - Blocks 9 and 10 will get merged into blocks 4 & 5 respectively which - enables CSE, DCE and other optimizations to occur on a larger block - of code. */ - -static bool -split_paths () -{ - bool changed = false; - - loop_optimizer_init (LOOPS_NORMAL | LOOPS_HAVE_RECORDED_EXITS); - initialize_original_copy_tables (); - calculate_dominance_info (CDI_DOMINATORS); - - for (auto loop : loops_list (cfun, LI_FROM_INNERMOST)) - { - /* Only split paths if we are optimizing this loop for speed. */ - if (!optimize_loop_for_speed_p (loop)) - continue; - - /* See if there is a block that we can duplicate to split the - path to the loop latch. */ - basic_block bb - = find_block_to_duplicate_for_splitting_paths (loop->latch); - - /* BB is the merge point for an IF-THEN-ELSE we want to transform. - - Essentially we want to create a duplicate of bb and redirect the - first predecessor of BB to the duplicate (leaving the second - predecessor as is. This will split the path leading to the latch - re-using BB to avoid useless copying. */ - if (bb && is_feasible_trace (bb)) - { - if (dump_file && (dump_flags & TDF_DETAILS)) - fprintf (dump_file, - "Duplicating join block %d into predecessor paths\n", - bb->index); - basic_block pred0 = EDGE_PRED (bb, 0)->src; - if (EDGE_COUNT (pred0->succs) != 1) - pred0 = EDGE_PRED (bb, 1)->src; - transform_duplicate (pred0, bb); - changed = true; - - /* If BB has an outgoing edge marked as IRREDUCIBLE, then - duplicating BB may result in an irreducible region turning - into a natural loop. - - Long term we might want to hook this into the block - duplication code, but as we've seen with similar changes - for edge removal, that can be somewhat risky. */ - if (EDGE_SUCC (bb, 0)->flags & EDGE_IRREDUCIBLE_LOOP - || EDGE_SUCC (bb, 1)->flags & EDGE_IRREDUCIBLE_LOOP) - { - if (dump_file && (dump_flags & TDF_DETAILS)) - fprintf (dump_file, - "Join block %d has EDGE_IRREDUCIBLE_LOOP set. " - "Scheduling loop fixups.\n", - bb->index); - loops_state_set (LOOPS_NEED_FIXUP); - } - } - } - - loop_optimizer_finalize (); - free_original_copy_tables (); - return changed; -} - -/* Main entry point for splitting paths. Returns TODO_cleanup_cfg if any - paths where split, otherwise return zero. */ - -static unsigned int -execute_split_paths () -{ - /* If we don't have at least 2 real blocks and backedges in the - CFG, then there's no point in trying to perform path splitting. */ - if (n_basic_blocks_for_fn (cfun) <= NUM_FIXED_BLOCKS + 1 - || !mark_dfs_back_edges ()) - return 0; - - bool changed = split_paths(); - if (changed) - free_dominance_info (CDI_DOMINATORS); - - return changed ? TODO_cleanup_cfg : 0; -} - -static bool -gate_split_paths () -{ - return flag_split_paths; -} - -namespace { - -const pass_data pass_data_split_paths = -{ - GIMPLE_PASS, /* type */ - "split-paths", /* name */ - OPTGROUP_NONE, /* optinfo_flags */ - TV_SPLIT_PATHS, /* tv_id */ - PROP_ssa, /* properties_required */ - 0, /* properties_provided */ - 0, /* properties_destroyed */ - 0, /* todo_flags_start */ - TODO_update_ssa, /* todo_flags_finish */ -}; - -class pass_split_paths : public gimple_opt_pass -{ - public: - pass_split_paths (gcc::context *ctxt) - : gimple_opt_pass (pass_data_split_paths, ctxt) - {} - /* opt_pass methods: */ - opt_pass * clone () final override { return new pass_split_paths (m_ctxt); } - bool gate (function *) final override { return gate_split_paths (); } - unsigned int execute (function *) final override - { - return execute_split_paths (); - } - -}; // class pass_split_paths - -} // anon namespace - -gimple_opt_pass * -make_pass_split_paths (gcc::context *ctxt) -{ - return new pass_split_paths (ctxt); -} diff --git a/gcc/opts.cc b/gcc/opts.cc index 342517528e8e..5522f41f9069 100644 --- a/gcc/opts.cc +++ b/gcc/opts.cc @@ -707,7 +707,6 @@ static const struct default_options default_options_table[] = { OPT_LEVELS_3_PLUS, OPT_fpeel_loops, NULL, 1 }, { OPT_LEVELS_3_PLUS, OPT_fpredictive_commoning, NULL, 1 }, { OPT_LEVELS_3_PLUS, OPT_fsplit_loops, NULL, 1 }, - { OPT_LEVELS_3_PLUS, OPT_fsplit_paths, NULL, 1 }, { OPT_LEVELS_3_PLUS, OPT_ftree_loop_distribution, NULL, 1 }, { OPT_LEVELS_3_PLUS, OPT_ftree_partial_pre, NULL, 1 }, { OPT_LEVELS_3_PLUS, OPT_funswitch_loops, NULL, 1 }, diff --git a/gcc/passes.def b/gcc/passes.def index 1fc867fae517..9095c134f49d 100644 --- a/gcc/passes.def +++ b/gcc/passes.def @@ -351,7 +351,6 @@ along with GCC; see the file COPYING3. If not see NEXT_PASS (pass_cse_reciprocals); NEXT_PASS (pass_reassoc, false /* early_p */); NEXT_PASS (pass_strength_reduction); - NEXT_PASS (pass_split_paths); NEXT_PASS (pass_tracer); NEXT_PASS (pass_fre, false /* may_iterate */); /* After late FRE we rewrite no longer addressed locals into SSA diff --git a/gcc/testsuite/g++.dg/torture/pr88797.C b/gcc/testsuite/g++.dg/torture/pr88797.C new file mode 100644 index 000000000000..3dd00fcb7a94 --- /dev/null +++ b/gcc/testsuite/g++.dg/torture/pr88797.C @@ -0,0 +1,13 @@ +/* { dg-do compile } */ + + +void use(unsigned); +bool f(unsigned x, unsigned y) { + return x < 1111 + (y <= 2222); +} +void test_f(unsigned x, unsigned y) { + for (unsigned i = 0; i < 3333; ++i) + use(f(x++, y++)); +} + + diff --git a/gcc/testsuite/g++.dg/tree-ssa/pr88797.C b/gcc/testsuite/g++.dg/tree-ssa/pr88797.C deleted file mode 100644 index 541ae8e71e13..000000000000 --- a/gcc/testsuite/g++.dg/tree-ssa/pr88797.C +++ /dev/null @@ -1,16 +0,0 @@ -/* { dg-do compile } */ -/* { dg-options "-O3 -fdump-tree-split-paths-details" } */ - - -void use(unsigned); -bool f(unsigned x, unsigned y) { - return x < 1111 + (y <= 2222); -} -void test_f(unsigned x, unsigned y) { - for (unsigned i = 0; i < 3333; ++i) - use(f(x++, y++)); -} - -/* { dg-final { scan-tree-dump-not "Duplicating join block" "split-paths" } } */ -/* { dg-final { scan-tree-dump-times "appears to be a join point for if-convertible bbs." 1 "split-paths" } } */ - diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr69270.c b/gcc/testsuite/gcc.c-torture/compile/pr69270.c similarity index 57% rename from gcc/testsuite/gcc.dg/tree-ssa/pr69270.c rename to gcc/testsuite/gcc.c-torture/compile/pr69270.c index b08ec9d6ddb4..daed456ec607 100644 --- a/gcc/testsuite/gcc.dg/tree-ssa/pr69270.c +++ b/gcc/testsuite/gcc.c-torture/compile/pr69270.c @@ -1,17 +1,10 @@ -/* { dg-do compile } */ -/* { dg-options "-O2 -fsplit-paths -fdump-tree-dom3-details" } */ /* There should be two references to bufferstep that turn into constants. */ -/* { dg-final { scan-tree-dump-times "Replaced .bufferstep_\[0-9\]+. with constant .0." 1 "dom3"} } */ -/* { dg-final { scan-tree-dump-times "Replaced .bufferstep_\[0-9\]+. with constant .1." 1 "dom3"} } */ /* And some assignments ought to fold down to constants. */ -/* { dg-final { scan-tree-dump-times "Folded to: (?:bufferstep)?_\[0-9\]+ = 1;" 1 "dom3"} } */ -/* { dg-final { scan-tree-dump-times "Folded to: (?:bufferstep)?_\[0-9\]+ = 0;" 1 "dom3"} } */ /* The XOR operations should have been optimized to constants. */ -/* { dg-final { scan-tree-dump-not "bit_xor" "dom3"} } */ extern int *stepsizeTable; diff --git a/gcc/testsuite/gcc.dg/tree-ssa/split-path-10.c b/gcc/testsuite/gcc.c-torture/compile/split-path-10.c similarity index 81% rename from gcc/testsuite/gcc.dg/tree-ssa/split-path-10.c rename to gcc/testsuite/gcc.c-torture/compile/split-path-10.c index ed2087954883..336b11893b6b 100644 --- a/gcc/testsuite/gcc.dg/tree-ssa/split-path-10.c +++ b/gcc/testsuite/gcc.c-torture/compile/split-path-10.c @@ -1,6 +1,4 @@ /* PR tree-optimization/79389 */ -/* { dg-do compile } */ -/* { dg-options "-O3 -fdump-tree-split-paths-details" } */ typedef struct { @@ -46,4 +44,3 @@ double MonteCarlo_integrate(int Num_samples) return ((double) under_curve / Num_samples) * 4.0; } -/* { dg-final { scan-tree-dump-times "Duplicating join block" 0 "split-paths" } } */ diff --git a/gcc/testsuite/gcc.dg/tree-ssa/split-path-11.c b/gcc/testsuite/gcc.c-torture/compile/split-path-11.c similarity index 55% rename from gcc/testsuite/gcc.dg/tree-ssa/split-path-11.c rename to gcc/testsuite/gcc.c-torture/compile/split-path-11.c index fa33367feaa7..44b8b0594817 100644 --- a/gcc/testsuite/gcc.dg/tree-ssa/split-path-11.c +++ b/gcc/testsuite/gcc.c-torture/compile/split-path-11.c @@ -1,5 +1,3 @@ -/* { dg-do compile } */ -/* { dg-options "-O2 -fno-tree-vectorize -fsplit-paths -fdump-tree-split-paths-details -w" } */ void foo(unsigned long long *M) { @@ -11,4 +9,3 @@ void foo(unsigned long long *M) } } -/* { dg-final { scan-tree-dump-times "join point for if-convertible" 1 "split-paths" } } */ diff --git a/gcc/testsuite/gcc.dg/tree-ssa/split-path-12.c b/gcc/testsuite/gcc.c-torture/compile/split-path-12.c similarity index 70% rename from gcc/testsuite/gcc.dg/tree-ssa/split-path-12.c rename to gcc/testsuite/gcc.c-torture/compile/split-path-12.c index da00f795ef02..dc9da4e90ef4 100644 --- a/gcc/testsuite/gcc.dg/tree-ssa/split-path-12.c +++ b/gcc/testsuite/gcc.c-torture/compile/split-path-12.c @@ -1,5 +1,3 @@ -/* { dg-do compile } */ -/* { dg-options "-O2 -fsplit-paths -fdump-tree-split-paths-details " } */ double foo(double *d1, double *d2, double *d3, int num, double *ip) @@ -18,4 +16,3 @@ foo(double *d1, double *d2, double *d3, int num, double *ip) /* Split-paths shouldn't do anything here, if there's a diamond it would be if-convertible. */ -/* { dg-final { scan-tree-dump-not "Duplicating join block" "split-paths" } } */ diff --git a/gcc/testsuite/gcc.dg/tree-ssa/split-path-13.c b/gcc/testsuite/gcc.c-torture/compile/split-path-13.c similarity index 62% rename from gcc/testsuite/gcc.dg/tree-ssa/split-path-13.c rename to gcc/testsuite/gcc.c-torture/compile/split-path-13.c index d24e23bc59d6..554ae4d8f398 100644 --- a/gcc/testsuite/gcc.dg/tree-ssa/split-path-13.c +++ b/gcc/testsuite/gcc.c-torture/compile/split-path-13.c @@ -1,5 +1,3 @@ -/* { dg-do compile } */ -/* { dg-options "-O2 -fsplit-paths -fdump-tree-split-paths-details " } */ /* PR tree-optimization/112402 */ /* This is similar to split-path-2.c but instead of the add being inside both sides, we have a constant. */ @@ -22,5 +20,4 @@ foo(signed char *p, int n) return s; } -/* { dg-final { scan-tree-dump "appears to be a join point for if-convertible" "split-paths" } } */ diff --git a/gcc/testsuite/gcc.c-torture/compile/split-path-2.c b/gcc/testsuite/gcc.c-torture/compile/split-path-2.c new file mode 100644 index 000000000000..9418c9488d4c --- /dev/null +++ b/gcc/testsuite/gcc.c-torture/compile/split-path-2.c @@ -0,0 +1,18 @@ + +int +foo(signed char *p, int n) +{ + int s = 0; + int i; + + for (i = 0; i < n; i++) { + if (p[i] >= 0) + s++; + else + s--; + } + + return s; +} + + diff --git a/gcc/testsuite/gcc.dg/tree-ssa/split-path-3.c b/gcc/testsuite/gcc.c-torture/compile/split-path-3.c similarity index 93% rename from gcc/testsuite/gcc.dg/tree-ssa/split-path-3.c rename to gcc/testsuite/gcc.c-torture/compile/split-path-3.c index f6a29f628a23..9ea9fb2fed13 100644 --- a/gcc/testsuite/gcc.dg/tree-ssa/split-path-3.c +++ b/gcc/testsuite/gcc.c-torture/compile/split-path-3.c @@ -1,5 +1,3 @@ -/* { dg-do compile } */ -/* { dg-options "-O2 -fsplit-paths -fdump-tree-split-paths-details -w" } */ typedef struct bitmap_head_def *bitmap; extern void vec_assert_fail (const char *, const char *, const char *file_, @@ -94,4 +92,3 @@ compute_idf (bitmap_head * dfs) (VEC_int_heap_free (&work_stack)); } -/* { dg-final { scan-tree-dump-not "Duplicating join block" "split-paths" } } */ diff --git a/gcc/testsuite/gcc.dg/tree-ssa/split-path-4.c b/gcc/testsuite/gcc.c-torture/compile/split-path-4.c similarity index 62% rename from gcc/testsuite/gcc.dg/tree-ssa/split-path-4.c rename to gcc/testsuite/gcc.c-torture/compile/split-path-4.c index cbee6fce4b74..6705f9e84261 100644 --- a/gcc/testsuite/gcc.dg/tree-ssa/split-path-4.c +++ b/gcc/testsuite/gcc.c-torture/compile/split-path-4.c @@ -1,5 +1,3 @@ -/* { dg-do compile } */ -/* { dg-options "-O2 -fsplit-paths -fdump-tree-split-paths-details -w -fdisable-tree-thread1 -fdisable-tree-thread2" } */ /* Note: Threader causes the infinite loop in val & 1 sooner. */ @@ -25,5 +23,4 @@ powi_cost (long n) } } -/* { dg-final { scan-tree-dump-times "Duplicating join block" 1 "split-paths" } } */ diff --git a/gcc/testsuite/gcc.dg/tree-ssa/split-path-5.c b/gcc/testsuite/gcc.c-torture/compile/split-path-5.c similarity index 84% rename from gcc/testsuite/gcc.dg/tree-ssa/split-path-5.c rename to gcc/testsuite/gcc.c-torture/compile/split-path-5.c index 2f5e7edcfa89..aff1f0381955 100644 --- a/gcc/testsuite/gcc.dg/tree-ssa/split-path-5.c +++ b/gcc/testsuite/gcc.c-torture/compile/split-path-5.c @@ -1,5 +1,3 @@ -/* { dg-do compile } */ -/* { dg-options "-O2 -fsplit-paths -fdump-tree-split-paths-details -w" } */ const extern signed char *__ctype_ptr__; typedef unsigned char uchar; @@ -41,4 +39,3 @@ bmhi_init (const signed char *pattern) } } -/* { dg-final { scan-tree-dump-times "join point for if-convertible" 1 "split-paths" } } */ diff --git a/gcc/testsuite/gcc.dg/tree-ssa/split-path-6.c b/gcc/testsuite/gcc.c-torture/compile/split-path-6.c similarity index 82% rename from gcc/testsuite/gcc.dg/tree-ssa/split-path-6.c rename to gcc/testsuite/gcc.c-torture/compile/split-path-6.c index e2b0a9571f0d..9c32c813b607 100644 --- a/gcc/testsuite/gcc.dg/tree-ssa/split-path-6.c +++ b/gcc/testsuite/gcc.c-torture/compile/split-path-6.c @@ -1,5 +1,3 @@ -/* { dg-do compile } */ -/* { dg-options "-O2 -fsplit-paths -fno-tree-cselim -fno-ssa-phiopt -fdump-tree-split-paths-details -fno-finite-loops -fno-tree-dominator-opts -fno-tree-vrp -w" } */ struct __sFILE { @@ -75,4 +73,3 @@ lookharder (char *string) } } -/* { dg-final { scan-tree-dump-times "Duplicating join block" 2 "split-paths" } } */ diff --git a/gcc/testsuite/gcc.dg/tree-ssa/split-path-7.c b/gcc/testsuite/gcc.c-torture/compile/split-path-7.c similarity index 87% rename from gcc/testsuite/gcc.dg/tree-ssa/split-path-7.c rename to gcc/testsuite/gcc.c-torture/compile/split-path-7.c index 35634ab3bd86..33d04b4ff7d1 100644 --- a/gcc/testsuite/gcc.dg/tree-ssa/split-path-7.c +++ b/gcc/testsuite/gcc.c-torture/compile/split-path-7.c @@ -1,5 +1,3 @@ -/* { dg-do compile } */ -/* { dg-options "-O2 -fsplit-paths -fno-tree-cselim -fno-ssa-phiopt -fno-tree-sink -fdump-tree-split-paths-details -w" } */ struct _reent @@ -91,4 +89,3 @@ linit () } } } -/* { dg-final { scan-tree-dump-times "Duplicating join block" 0 "split-paths" } } */ diff --git a/gcc/testsuite/gcc.c-torture/compile/split-path-8.c b/gcc/testsuite/gcc.c-torture/compile/split-path-8.c new file mode 100644 index 000000000000..cccbf0ca0a3b --- /dev/null +++ b/gcc/testsuite/gcc.c-torture/compile/split-path-8.c @@ -0,0 +1,11 @@ +/* PR77283 */ + +void +foo (double *x, double *a, double *b, long n, double limit) +{ + long i; + for (i=0; i < n; i++) + if (a[i] < limit) + x[i] = b[i]; +} + diff --git a/gcc/testsuite/gcc.c-torture/compile/split-path-9.c b/gcc/testsuite/gcc.c-torture/compile/split-path-9.c new file mode 100644 index 000000000000..4eacad2978a3 --- /dev/null +++ b/gcc/testsuite/gcc.c-torture/compile/split-path-9.c @@ -0,0 +1,14 @@ +/* PR77366 */ + +void +foo(unsigned int size, unsigned int *state) +{ + unsigned int i; + + for(i = 0; i < size; i++) + { + if(state[i] & 1) + state[i] ^= 1; + } +} + diff --git a/gcc/testsuite/gcc.dg/tree-ssa/split-path-1.c b/gcc/testsuite/gcc.c-torture/execute/split-path-1.c similarity index 83% rename from gcc/testsuite/gcc.dg/tree-ssa/split-path-1.c rename to gcc/testsuite/gcc.c-torture/execute/split-path-1.c index b670dee8d102..e0ca386b4eab 100644 --- a/gcc/testsuite/gcc.dg/tree-ssa/split-path-1.c +++ b/gcc/testsuite/gcc.c-torture/execute/split-path-1.c @@ -1,6 +1,4 @@ -/* { dg-do run } */ /* Note both PHI-OPT and the loop if conversion pass converts the inner if to be branchless using min/max. */ -/* { dg-options "-O2 -fsplit-paths -fdump-tree-split-paths-details --param max-jump-thread-duplication-stmts=20 -fno-ssa-phiopt -fno-tree-loop-if-convert" } */ #include #include @@ -67,4 +65,3 @@ main() return 0; } -/* { dg-final { scan-tree-dump "Duplicating join block" "split-paths" } } */ diff --git a/gcc/testsuite/gcc.dg/tree-ssa/split-path-2.c b/gcc/testsuite/gcc.dg/tree-ssa/split-path-2.c deleted file mode 100644 index 61697a35e560..000000000000 --- a/gcc/testsuite/gcc.dg/tree-ssa/split-path-2.c +++ /dev/null @@ -1,21 +0,0 @@ -/* { dg-do compile } */ -/* { dg-options "-O2 -fsplit-paths -fdump-tree-split-paths-details " } */ - -int -foo(signed char *p, int n) -{ - int s = 0; - int i; - - for (i = 0; i < n; i++) { - if (p[i] >= 0) - s++; - else - s--; - } - - return s; -} - -/* { dg-final { scan-tree-dump "appears to be a join point for if-convertible" "split-paths" } } */ - diff --git a/gcc/testsuite/gcc.dg/tree-ssa/split-path-8.c b/gcc/testsuite/gcc.dg/tree-ssa/split-path-8.c deleted file mode 100644 index fb54f5dc512e..000000000000 --- a/gcc/testsuite/gcc.dg/tree-ssa/split-path-8.c +++ /dev/null @@ -1,14 +0,0 @@ -/* PR77283 */ -/* { dg-do compile } */ -/* { dg-options "-O3 -fdump-tree-split-paths-details" } */ - -void -foo (double *x, double *a, double *b, long n, double limit) -{ - long i; - for (i=0; i < n; i++) - if (a[i] < limit) - x[i] = b[i]; -} - -/* { dg-final { scan-tree-dump-times "Duplicating join block" 0 "split-paths" } } */ diff --git a/gcc/testsuite/gcc.dg/tree-ssa/split-path-9.c b/gcc/testsuite/gcc.dg/tree-ssa/split-path-9.c deleted file mode 100644 index 8be0cd01201f..000000000000 --- a/gcc/testsuite/gcc.dg/tree-ssa/split-path-9.c +++ /dev/null @@ -1,17 +0,0 @@ -/* PR77366 */ -/* { dg-do compile } */ -/* { dg-options "-O3 -fdump-tree-split-paths-details" } */ - -void -foo(unsigned int size, unsigned int *state) -{ - unsigned int i; - - for(i = 0; i < size; i++) - { - if(state[i] & 1) - state[i] ^= 1; - } -} - -/* { dg-final { scan-tree-dump-times "Duplicating join block" 0 "split-paths" } } */ diff --git a/gcc/testsuite/gcc.target/i386/pr106450.c b/gcc/testsuite/gcc.target/i386/pr106450.c index d16231f6abd1..009e3eb8c743 100644 --- a/gcc/testsuite/gcc.target/i386/pr106450.c +++ b/gcc/testsuite/gcc.target/i386/pr106450.c @@ -1,5 +1,5 @@ /* { dg-do compile { target int128 } } */ -/* { dg-options "-O2 -fsplit-paths" } */ +/* { dg-options "-O2" } */ __int128 n; diff --git a/gcc/timevar.def b/gcc/timevar.def index 588d987ec356..c70209976096 100644 --- a/gcc/timevar.def +++ b/gcc/timevar.def @@ -287,7 +287,6 @@ DEFTIMEVAR (TV_GCSE_AFTER_RELOAD , "load CSE after reload") DEFTIMEVAR (TV_REE , "ree") DEFTIMEVAR (TV_THREAD_PROLOGUE_AND_EPILOGUE, "thread pro- & epilogue") DEFTIMEVAR (TV_IFCVT2 , "if-conversion 2") -DEFTIMEVAR (TV_SPLIT_PATHS , "split paths") DEFTIMEVAR (TV_COMBINE_STACK_ADJUST , "combine stack adjustments") DEFTIMEVAR (TV_PEEPHOLE2 , "peephole 2") DEFTIMEVAR (TV_RENAME_REGISTERS , "rename registers") diff --git a/gcc/tree-pass.h b/gcc/tree-pass.h index b3c97658a8fe..a3b35e009e08 100644 --- a/gcc/tree-pass.h +++ b/gcc/tree-pass.h @@ -404,7 +404,6 @@ extern gimple_opt_pass *make_pass_ch (gcc::context *ctxt); extern gimple_opt_pass *make_pass_ch_vect (gcc::context *ctxt); extern gimple_opt_pass *make_pass_sccopy (gcc::context *ctxt); extern gimple_opt_pass *make_pass_ccp (gcc::context *ctxt); -extern gimple_opt_pass *make_pass_split_paths (gcc::context *ctxt); extern gimple_opt_pass *make_pass_build_ssa (gcc::context *ctxt); extern gimple_opt_pass *make_pass_build_alias (gcc::context *ctxt); extern gimple_opt_pass *make_pass_build_ealias (gcc::context *ctxt);