| /* Function splitting pass |
| Copyright (C) 2010-2017 Free Software Foundation, Inc. |
| Contributed by Jan Hubicka <jh@suse.cz> |
| |
| 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 |
| <http://www.gnu.org/licenses/>. */ |
| |
| /* The purpose of this pass is to split function bodies to improve |
| inlining. I.e. for function of the form: |
| |
| func (...) |
| { |
| if (cheap_test) |
| something_small |
| else |
| something_big |
| } |
| |
| Produce: |
| |
| func.part (...) |
| { |
| something_big |
| } |
| |
| func (...) |
| { |
| if (cheap_test) |
| something_small |
| else |
| func.part (...); |
| } |
| |
| When func becomes inlinable and when cheap_test is often true, inlining func, |
| but not fund.part leads to performance improvement similar as inlining |
| original func while the code size growth is smaller. |
| |
| The pass is organized in three stages: |
| 1) Collect local info about basic block into BB_INFO structure and |
| compute function body estimated size and time. |
| 2) Via DFS walk find all possible basic blocks where we can split |
| and chose best one. |
| 3) If split point is found, split at the specified BB by creating a clone |
| and updating function to call it. |
| |
| The decisions what functions to split are in execute_split_functions |
| and consider_split. |
| |
| There are several possible future improvements for this pass including: |
| |
| 1) Splitting to break up large functions |
| 2) Splitting to reduce stack frame usage |
| 3) Allow split part of function to use values computed in the header part. |
| The values needs to be passed to split function, perhaps via same |
| interface as for nested functions or as argument. |
| 4) Support for simple rematerialization. I.e. when split part use |
| value computed in header from function parameter in very cheap way, we |
| can just recompute it. |
| 5) Support splitting of nested functions. |
| 6) Support non-SSA arguments. |
| 7) There is nothing preventing us from producing multiple parts of single function |
| when needed or splitting also the parts. */ |
| |
| #include "config.h" |
| #include "system.h" |
| #include "coretypes.h" |
| #include "backend.h" |
| #include "rtl.h" |
| #include "tree.h" |
| #include "gimple.h" |
| #include "cfghooks.h" |
| #include "alloc-pool.h" |
| #include "tree-pass.h" |
| #include "ssa.h" |
| #include "cgraph.h" |
| #include "diagnostic.h" |
| #include "fold-const.h" |
| #include "cfganal.h" |
| #include "calls.h" |
| #include "gimplify.h" |
| #include "gimple-iterator.h" |
| #include "gimplify-me.h" |
| #include "gimple-walk.h" |
| #include "symbol-summary.h" |
| #include "ipa-prop.h" |
| #include "tree-cfg.h" |
| #include "tree-into-ssa.h" |
| #include "tree-dfa.h" |
| #include "tree-inline.h" |
| #include "params.h" |
| #include "gimple-pretty-print.h" |
| #include "ipa-inline.h" |
| #include "cfgloop.h" |
| #include "tree-chkp.h" |
| |
| /* Per basic block info. */ |
| |
| struct split_bb_info |
| { |
| unsigned int size; |
| unsigned int time; |
| }; |
| |
| static vec<split_bb_info> bb_info_vec; |
| |
| /* Description of split point. */ |
| |
| struct split_point |
| { |
| /* Size of the partitions. */ |
| unsigned int header_time, header_size, split_time, split_size; |
| |
| /* SSA names that need to be passed into spit function. */ |
| bitmap ssa_names_to_pass; |
| |
| /* Basic block where we split (that will become entry point of new function. */ |
| basic_block entry_bb; |
| |
| /* Basic blocks we are splitting away. */ |
| bitmap split_bbs; |
| |
| /* True when return value is computed on split part and thus it needs |
| to be returned. */ |
| bool split_part_set_retval; |
| }; |
| |
| /* Best split point found. */ |
| |
| struct split_point best_split_point; |
| |
| /* Set of basic blocks that are not allowed to dominate a split point. */ |
| |
| static bitmap forbidden_dominators; |
| |
| static tree find_retval (basic_block return_bb); |
| static tree find_retbnd (basic_block return_bb); |
| |
| /* Callback for walk_stmt_load_store_addr_ops. If T is non-SSA automatic |
| variable, check it if it is present in bitmap passed via DATA. */ |
| |
| static bool |
| test_nonssa_use (gimple *, tree t, tree, void *data) |
| { |
| t = get_base_address (t); |
| |
| if (!t || is_gimple_reg (t)) |
| return false; |
| |
| if (TREE_CODE (t) == PARM_DECL |
| || (VAR_P (t) |
| && auto_var_in_fn_p (t, current_function_decl)) |
| || TREE_CODE (t) == RESULT_DECL |
| /* Normal labels are part of CFG and will be handled gratefuly. |
| Forced labels however can be used directly by statements and |
| need to stay in one partition along with their uses. */ |
| || (TREE_CODE (t) == LABEL_DECL |
| && FORCED_LABEL (t))) |
| return bitmap_bit_p ((bitmap)data, DECL_UID (t)); |
| |
| /* For DECL_BY_REFERENCE, the return value is actually a pointer. We want |
| to pretend that the value pointed to is actual result decl. */ |
| if ((TREE_CODE (t) == MEM_REF || INDIRECT_REF_P (t)) |
| && TREE_CODE (TREE_OPERAND (t, 0)) == SSA_NAME |
| && SSA_NAME_VAR (TREE_OPERAND (t, 0)) |
| && TREE_CODE (SSA_NAME_VAR (TREE_OPERAND (t, 0))) == RESULT_DECL |
| && DECL_BY_REFERENCE (DECL_RESULT (current_function_decl))) |
| return |
| bitmap_bit_p ((bitmap)data, |
| DECL_UID (DECL_RESULT (current_function_decl))); |
| |
| return false; |
| } |
| |
| /* Dump split point CURRENT. */ |
| |
| static void |
| dump_split_point (FILE * file, struct split_point *current) |
| { |
| fprintf (file, |
| "Split point at BB %i\n" |
| " header time: %i header size: %i\n" |
| " split time: %i split size: %i\n bbs: ", |
| current->entry_bb->index, current->header_time, |
| current->header_size, current->split_time, current->split_size); |
| dump_bitmap (file, current->split_bbs); |
| fprintf (file, " SSA names to pass: "); |
| dump_bitmap (file, current->ssa_names_to_pass); |
| } |
| |
| /* Look for all BBs in header that might lead to the split part and verify |
| that they are not defining any non-SSA var used by the split part. |
| Parameters are the same as for consider_split. */ |
| |
| static bool |
| verify_non_ssa_vars (struct split_point *current, bitmap non_ssa_vars, |
| basic_block return_bb) |
| { |
| bitmap seen = BITMAP_ALLOC (NULL); |
| vec<basic_block> worklist = vNULL; |
| edge e; |
| edge_iterator ei; |
| bool ok = true; |
| basic_block bb; |
| |
| FOR_EACH_EDGE (e, ei, current->entry_bb->preds) |
| if (e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun) |
| && !bitmap_bit_p (current->split_bbs, e->src->index)) |
| { |
| worklist.safe_push (e->src); |
| bitmap_set_bit (seen, e->src->index); |
| } |
| |
| while (!worklist.is_empty ()) |
| { |
| bb = worklist.pop (); |
| FOR_EACH_EDGE (e, ei, bb->preds) |
| if (e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun) |
| && bitmap_set_bit (seen, e->src->index)) |
| { |
| gcc_checking_assert (!bitmap_bit_p (current->split_bbs, |
| e->src->index)); |
| worklist.safe_push (e->src); |
| } |
| for (gimple_stmt_iterator bsi = gsi_start_bb (bb); !gsi_end_p (bsi); |
| gsi_next (&bsi)) |
| { |
| gimple *stmt = gsi_stmt (bsi); |
| if (is_gimple_debug (stmt)) |
| continue; |
| if (walk_stmt_load_store_addr_ops |
| (stmt, non_ssa_vars, test_nonssa_use, test_nonssa_use, |
| test_nonssa_use)) |
| { |
| ok = false; |
| goto done; |
| } |
| if (glabel *label_stmt = dyn_cast <glabel *> (stmt)) |
| if (test_nonssa_use (stmt, gimple_label_label (label_stmt), |
| NULL_TREE, non_ssa_vars)) |
| { |
| ok = false; |
| goto done; |
| } |
| } |
| for (gphi_iterator bsi = gsi_start_phis (bb); !gsi_end_p (bsi); |
| gsi_next (&bsi)) |
| { |
| if (walk_stmt_load_store_addr_ops |
| (gsi_stmt (bsi), non_ssa_vars, test_nonssa_use, test_nonssa_use, |
| test_nonssa_use)) |
| { |
| ok = false; |
| goto done; |
| } |
| } |
| FOR_EACH_EDGE (e, ei, bb->succs) |
| { |
| if (e->dest != return_bb) |
| continue; |
| for (gphi_iterator bsi = gsi_start_phis (return_bb); |
| !gsi_end_p (bsi); |
| gsi_next (&bsi)) |
| { |
| gphi *stmt = bsi.phi (); |
| tree op = gimple_phi_arg_def (stmt, e->dest_idx); |
| |
| if (virtual_operand_p (gimple_phi_result (stmt))) |
| continue; |
| if (TREE_CODE (op) != SSA_NAME |
| && test_nonssa_use (stmt, op, op, non_ssa_vars)) |
| { |
| ok = false; |
| goto done; |
| } |
| } |
| } |
| } |
| |
| /* Verify that the rest of function does not define any label |
| used by the split part. */ |
| FOR_EACH_BB_FN (bb, cfun) |
| if (!bitmap_bit_p (current->split_bbs, bb->index) |
| && !bitmap_bit_p (seen, bb->index)) |
| { |
| gimple_stmt_iterator bsi; |
| for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi); gsi_next (&bsi)) |
| if (glabel *label_stmt = dyn_cast <glabel *> (gsi_stmt (bsi))) |
| { |
| if (test_nonssa_use (label_stmt, |
| gimple_label_label (label_stmt), |
| NULL_TREE, non_ssa_vars)) |
| { |
| ok = false; |
| goto done; |
| } |
| } |
| else |
| break; |
| } |
| |
| done: |
| BITMAP_FREE (seen); |
| worklist.release (); |
| return ok; |
| } |
| |
| /* If STMT is a call, check the callee against a list of forbidden |
| predicate functions. If a match is found, look for uses of the |
| call result in condition statements that compare against zero. |
| For each such use, find the block targeted by the condition |
| statement for the nonzero result, and set the bit for this block |
| in the forbidden dominators bitmap. The purpose of this is to avoid |
| selecting a split point where we are likely to lose the chance |
| to optimize away an unused function call. */ |
| |
| static void |
| check_forbidden_calls (gimple *stmt) |
| { |
| imm_use_iterator use_iter; |
| use_operand_p use_p; |
| tree lhs; |
| |
| /* At the moment, __builtin_constant_p is the only forbidden |
| predicate function call (see PR49642). */ |
| if (!gimple_call_builtin_p (stmt, BUILT_IN_CONSTANT_P)) |
| return; |
| |
| lhs = gimple_call_lhs (stmt); |
| |
| if (!lhs || TREE_CODE (lhs) != SSA_NAME) |
| return; |
| |
| FOR_EACH_IMM_USE_FAST (use_p, use_iter, lhs) |
| { |
| tree op1; |
| basic_block use_bb, forbidden_bb; |
| enum tree_code code; |
| edge true_edge, false_edge; |
| gcond *use_stmt; |
| |
| use_stmt = dyn_cast <gcond *> (USE_STMT (use_p)); |
| if (!use_stmt) |
| continue; |
| |
| /* Assuming canonical form for GIMPLE_COND here, with constant |
| in second position. */ |
| op1 = gimple_cond_rhs (use_stmt); |
| code = gimple_cond_code (use_stmt); |
| use_bb = gimple_bb (use_stmt); |
| |
| extract_true_false_edges_from_block (use_bb, &true_edge, &false_edge); |
| |
| /* We're only interested in comparisons that distinguish |
| unambiguously from zero. */ |
| if (!integer_zerop (op1) || code == LE_EXPR || code == GE_EXPR) |
| continue; |
| |
| if (code == EQ_EXPR) |
| forbidden_bb = false_edge->dest; |
| else |
| forbidden_bb = true_edge->dest; |
| |
| bitmap_set_bit (forbidden_dominators, forbidden_bb->index); |
| } |
| } |
| |
| /* If BB is dominated by any block in the forbidden dominators set, |
| return TRUE; else FALSE. */ |
| |
| static bool |
| dominated_by_forbidden (basic_block bb) |
| { |
| unsigned dom_bb; |
| bitmap_iterator bi; |
| |
| EXECUTE_IF_SET_IN_BITMAP (forbidden_dominators, 1, dom_bb, bi) |
| { |
| if (dominated_by_p (CDI_DOMINATORS, bb, |
| BASIC_BLOCK_FOR_FN (cfun, dom_bb))) |
| return true; |
| } |
| |
| return false; |
| } |
| |
| /* For give split point CURRENT and return block RETURN_BB return 1 |
| if ssa name VAL is set by split part and 0 otherwise. */ |
| static bool |
| split_part_set_ssa_name_p (tree val, struct split_point *current, |
| basic_block return_bb) |
| { |
| if (TREE_CODE (val) != SSA_NAME) |
| return false; |
| |
| return (!SSA_NAME_IS_DEFAULT_DEF (val) |
| && (bitmap_bit_p (current->split_bbs, |
| gimple_bb (SSA_NAME_DEF_STMT (val))->index) |
| || gimple_bb (SSA_NAME_DEF_STMT (val)) == return_bb)); |
| } |
| |
| /* We found an split_point CURRENT. NON_SSA_VARS is bitmap of all non ssa |
| variables used and RETURN_BB is return basic block. |
| See if we can split function here. */ |
| |
| static void |
| consider_split (struct split_point *current, bitmap non_ssa_vars, |
| basic_block return_bb) |
| { |
| tree parm; |
| unsigned int num_args = 0; |
| unsigned int call_overhead; |
| edge e; |
| edge_iterator ei; |
| gphi_iterator bsi; |
| unsigned int i; |
| int incoming_freq = 0; |
| tree retval; |
| tree retbnd; |
| bool back_edge = false; |
| |
| if (dump_file && (dump_flags & TDF_DETAILS)) |
| dump_split_point (dump_file, current); |
| |
| FOR_EACH_EDGE (e, ei, current->entry_bb->preds) |
| { |
| if (e->flags & EDGE_DFS_BACK) |
| back_edge = true; |
| if (!bitmap_bit_p (current->split_bbs, e->src->index)) |
| incoming_freq += EDGE_FREQUENCY (e); |
| } |
| |
| /* Do not split when we would end up calling function anyway. */ |
| if (incoming_freq |
| >= (ENTRY_BLOCK_PTR_FOR_FN (cfun)->frequency |
| * PARAM_VALUE (PARAM_PARTIAL_INLINING_ENTRY_PROBABILITY) / 100)) |
| { |
| /* When profile is guessed, we can not expect it to give us |
| realistic estimate on likelyness of function taking the |
| complex path. As a special case, when tail of the function is |
| a loop, enable splitting since inlining code skipping the loop |
| is likely noticeable win. */ |
| if (back_edge |
| && profile_status_for_fn (cfun) != PROFILE_READ |
| && incoming_freq < ENTRY_BLOCK_PTR_FOR_FN (cfun)->frequency) |
| { |
| if (dump_file && (dump_flags & TDF_DETAILS)) |
| fprintf (dump_file, |
| " Split before loop, accepting despite low frequencies %i %i.\n", |
| incoming_freq, |
| ENTRY_BLOCK_PTR_FOR_FN (cfun)->frequency); |
| } |
| else |
| { |
| if (dump_file && (dump_flags & TDF_DETAILS)) |
| fprintf (dump_file, |
| " Refused: incoming frequency is too large.\n"); |
| return; |
| } |
| } |
| |
| if (!current->header_size) |
| { |
| if (dump_file && (dump_flags & TDF_DETAILS)) |
| fprintf (dump_file, " Refused: header empty\n"); |
| return; |
| } |
| |
| /* Verify that PHI args on entry are either virtual or all their operands |
| incoming from header are the same. */ |
| for (bsi = gsi_start_phis (current->entry_bb); !gsi_end_p (bsi); gsi_next (&bsi)) |
| { |
| gphi *stmt = bsi.phi (); |
| tree val = NULL; |
| |
| if (virtual_operand_p (gimple_phi_result (stmt))) |
| continue; |
| for (i = 0; i < gimple_phi_num_args (stmt); i++) |
| { |
| edge e = gimple_phi_arg_edge (stmt, i); |
| if (!bitmap_bit_p (current->split_bbs, e->src->index)) |
| { |
| tree edge_val = gimple_phi_arg_def (stmt, i); |
| if (val && edge_val != val) |
| { |
| if (dump_file && (dump_flags & TDF_DETAILS)) |
| fprintf (dump_file, |
| " Refused: entry BB has PHI with multiple variants\n"); |
| return; |
| } |
| val = edge_val; |
| } |
| } |
| } |
| |
| |
| /* See what argument we will pass to the split function and compute |
| call overhead. */ |
| call_overhead = eni_size_weights.call_cost; |
| for (parm = DECL_ARGUMENTS (current_function_decl); parm; |
| parm = DECL_CHAIN (parm)) |
| { |
| if (!is_gimple_reg (parm)) |
| { |
| if (bitmap_bit_p (non_ssa_vars, DECL_UID (parm))) |
| { |
| if (dump_file && (dump_flags & TDF_DETAILS)) |
| fprintf (dump_file, |
| " Refused: need to pass non-ssa param values\n"); |
| return; |
| } |
| } |
| else |
| { |
| tree ddef = ssa_default_def (cfun, parm); |
| if (ddef |
| && bitmap_bit_p (current->ssa_names_to_pass, |
| SSA_NAME_VERSION (ddef))) |
| { |
| if (!VOID_TYPE_P (TREE_TYPE (parm))) |
| call_overhead += estimate_move_cost (TREE_TYPE (parm), false); |
| num_args++; |
| } |
| } |
| } |
| if (!VOID_TYPE_P (TREE_TYPE (current_function_decl))) |
| call_overhead += estimate_move_cost (TREE_TYPE (current_function_decl), |
| false); |
| |
| if (current->split_size <= call_overhead) |
| { |
| if (dump_file && (dump_flags & TDF_DETAILS)) |
| fprintf (dump_file, |
| " Refused: split size is smaller than call overhead\n"); |
| return; |
| } |
| if (current->header_size + call_overhead |
| >= (unsigned int)(DECL_DECLARED_INLINE_P (current_function_decl) |
| ? MAX_INLINE_INSNS_SINGLE |
| : MAX_INLINE_INSNS_AUTO)) |
| { |
| if (dump_file && (dump_flags & TDF_DETAILS)) |
| fprintf (dump_file, |
| " Refused: header size is too large for inline candidate\n"); |
| return; |
| } |
| |
| /* Splitting functions brings the target out of comdat group; this will |
| lead to code duplication if the function is reused by other unit. |
| Limit this duplication. This is consistent with limit in tree-sra.c |
| FIXME: with LTO we ought to be able to do better! */ |
| if (DECL_ONE_ONLY (current_function_decl) |
| && current->split_size >= (unsigned int) MAX_INLINE_INSNS_AUTO) |
| { |
| if (dump_file && (dump_flags & TDF_DETAILS)) |
| fprintf (dump_file, |
| " Refused: function is COMDAT and tail is too large\n"); |
| return; |
| } |
| /* For comdat functions also reject very small tails; those will likely get |
| inlined back and we do not want to risk the duplication overhead. |
| FIXME: with LTO we ought to be able to do better! */ |
| if (DECL_ONE_ONLY (current_function_decl) |
| && current->split_size |
| <= (unsigned int) PARAM_VALUE (PARAM_EARLY_INLINING_INSNS) / 2) |
| { |
| if (dump_file && (dump_flags & TDF_DETAILS)) |
| fprintf (dump_file, |
| " Refused: function is COMDAT and tail is too small\n"); |
| return; |
| } |
| |
| /* FIXME: we currently can pass only SSA function parameters to the split |
| arguments. Once parm_adjustment infrastructure is supported by cloning, |
| we can pass more than that. */ |
| if (num_args != bitmap_count_bits (current->ssa_names_to_pass)) |
| { |
| |
| if (dump_file && (dump_flags & TDF_DETAILS)) |
| fprintf (dump_file, |
| " Refused: need to pass non-param values\n"); |
| return; |
| } |
| |
| /* When there are non-ssa vars used in the split region, see if they |
| are used in the header region. If so, reject the split. |
| FIXME: we can use nested function support to access both. */ |
| if (!bitmap_empty_p (non_ssa_vars) |
| && !verify_non_ssa_vars (current, non_ssa_vars, return_bb)) |
| { |
| if (dump_file && (dump_flags & TDF_DETAILS)) |
| fprintf (dump_file, |
| " Refused: split part has non-ssa uses\n"); |
| return; |
| } |
| |
| /* If the split point is dominated by a forbidden block, reject |
| the split. */ |
| if (!bitmap_empty_p (forbidden_dominators) |
| && dominated_by_forbidden (current->entry_bb)) |
| { |
| if (dump_file && (dump_flags & TDF_DETAILS)) |
| fprintf (dump_file, |
| " Refused: split point dominated by forbidden block\n"); |
| return; |
| } |
| |
| /* See if retval used by return bb is computed by header or split part. |
| When it is computed by split part, we need to produce return statement |
| in the split part and add code to header to pass it around. |
| |
| This is bit tricky to test: |
| 1) When there is no return_bb or no return value, we always pass |
| value around. |
| 2) Invariants are always computed by caller. |
| 3) For SSA we need to look if defining statement is in header or split part |
| 4) For non-SSA we need to look where the var is computed. */ |
| retval = find_retval (return_bb); |
| if (!retval) |
| { |
| /* If there is a return_bb with no return value in function returning |
| value by reference, also make the split part return void, otherwise |
| we expansion would try to create a non-POD temporary, which is |
| invalid. */ |
| if (return_bb != EXIT_BLOCK_PTR_FOR_FN (cfun) |
| && DECL_RESULT (current_function_decl) |
| && DECL_BY_REFERENCE (DECL_RESULT (current_function_decl))) |
| current->split_part_set_retval = false; |
| else |
| current->split_part_set_retval = true; |
| } |
| else if (is_gimple_min_invariant (retval)) |
| current->split_part_set_retval = false; |
| /* Special case is value returned by reference we record as if it was non-ssa |
| set to result_decl. */ |
| else if (TREE_CODE (retval) == SSA_NAME |
| && SSA_NAME_VAR (retval) |
| && TREE_CODE (SSA_NAME_VAR (retval)) == RESULT_DECL |
| && DECL_BY_REFERENCE (DECL_RESULT (current_function_decl))) |
| current->split_part_set_retval |
| = bitmap_bit_p (non_ssa_vars, DECL_UID (SSA_NAME_VAR (retval))); |
| else if (TREE_CODE (retval) == SSA_NAME) |
| current->split_part_set_retval |
| = split_part_set_ssa_name_p (retval, current, return_bb); |
| else if (TREE_CODE (retval) == PARM_DECL) |
| current->split_part_set_retval = false; |
| else if (VAR_P (retval) |
| || TREE_CODE (retval) == RESULT_DECL) |
| current->split_part_set_retval |
| = bitmap_bit_p (non_ssa_vars, DECL_UID (retval)); |
| else |
| current->split_part_set_retval = true; |
| |
| /* See if retbnd used by return bb is computed by header or split part. */ |
| retbnd = find_retbnd (return_bb); |
| if (retbnd) |
| { |
| bool split_part_set_retbnd |
| = split_part_set_ssa_name_p (retbnd, current, return_bb); |
| |
| /* If we have both return value and bounds then keep their definitions |
| in a single function. We use SSA names to link returned bounds and |
| value and therefore do not handle cases when result is passed by |
| reference (which should not be our case anyway since bounds are |
| returned for pointers only). */ |
| if ((DECL_BY_REFERENCE (DECL_RESULT (current_function_decl)) |
| && current->split_part_set_retval) |
| || split_part_set_retbnd != current->split_part_set_retval) |
| { |
| if (dump_file && (dump_flags & TDF_DETAILS)) |
| fprintf (dump_file, |
| " Refused: split point splits return value and bounds\n"); |
| return; |
| } |
| } |
| |
| /* split_function fixes up at most one PHI non-virtual PHI node in return_bb, |
| for the return value. If there are other PHIs, give up. */ |
| if (return_bb != EXIT_BLOCK_PTR_FOR_FN (cfun)) |
| { |
| gphi_iterator psi; |
| |
| for (psi = gsi_start_phis (return_bb); !gsi_end_p (psi); gsi_next (&psi)) |
| if (!virtual_operand_p (gimple_phi_result (psi.phi ())) |
| && !(retval |
| && current->split_part_set_retval |
| && TREE_CODE (retval) == SSA_NAME |
| && !DECL_BY_REFERENCE (DECL_RESULT (current_function_decl)) |
| && SSA_NAME_DEF_STMT (retval) == psi.phi ())) |
| { |
| if (dump_file && (dump_flags & TDF_DETAILS)) |
| fprintf (dump_file, |
| " Refused: return bb has extra PHIs\n"); |
| return; |
| } |
| } |
| |
| if (dump_file && (dump_flags & TDF_DETAILS)) |
| fprintf (dump_file, " Accepted!\n"); |
| |
| /* At the moment chose split point with lowest frequency and that leaves |
| out smallest size of header. |
| In future we might re-consider this heuristics. */ |
| if (!best_split_point.split_bbs |
| || best_split_point.entry_bb->frequency > current->entry_bb->frequency |
| || (best_split_point.entry_bb->frequency == current->entry_bb->frequency |
| && best_split_point.split_size < current->split_size)) |
| |
| { |
| if (dump_file && (dump_flags & TDF_DETAILS)) |
| fprintf (dump_file, " New best split point!\n"); |
| if (best_split_point.ssa_names_to_pass) |
| { |
| BITMAP_FREE (best_split_point.ssa_names_to_pass); |
| BITMAP_FREE (best_split_point.split_bbs); |
| } |
| best_split_point = *current; |
| best_split_point.ssa_names_to_pass = BITMAP_ALLOC (NULL); |
| bitmap_copy (best_split_point.ssa_names_to_pass, |
| current->ssa_names_to_pass); |
| best_split_point.split_bbs = BITMAP_ALLOC (NULL); |
| bitmap_copy (best_split_point.split_bbs, current->split_bbs); |
| } |
| } |
| |
| /* Return basic block containing RETURN statement. We allow basic blocks |
| of the form: |
| <retval> = tmp_var; |
| return <retval> |
| but return_bb can not be more complex than this (except for |
| -fsanitize=thread we allow TSAN_FUNC_EXIT () internal call in there). |
| If nothing is found, return the exit block. |
| |
| When there are multiple RETURN statement, chose one with return value, |
| since that one is more likely shared by multiple code paths. |
| |
| Return BB is special, because for function splitting it is the only |
| basic block that is duplicated in between header and split part of the |
| function. |
| |
| TODO: We might support multiple return blocks. */ |
| |
| static basic_block |
| find_return_bb (void) |
| { |
| edge e; |
| basic_block return_bb = EXIT_BLOCK_PTR_FOR_FN (cfun); |
| gimple_stmt_iterator bsi; |
| bool found_return = false; |
| tree retval = NULL_TREE; |
| |
| if (!single_pred_p (EXIT_BLOCK_PTR_FOR_FN (cfun))) |
| return return_bb; |
| |
| e = single_pred_edge (EXIT_BLOCK_PTR_FOR_FN (cfun)); |
| for (bsi = gsi_last_bb (e->src); !gsi_end_p (bsi); gsi_prev (&bsi)) |
| { |
| gimple *stmt = gsi_stmt (bsi); |
| if (gimple_code (stmt) == GIMPLE_LABEL |
| || is_gimple_debug (stmt) |
| || gimple_clobber_p (stmt)) |
| ; |
| else if (gimple_code (stmt) == GIMPLE_ASSIGN |
| && found_return |
| && gimple_assign_single_p (stmt) |
| && (auto_var_in_fn_p (gimple_assign_rhs1 (stmt), |
| current_function_decl) |
| || is_gimple_min_invariant (gimple_assign_rhs1 (stmt))) |
| && retval == gimple_assign_lhs (stmt)) |
| ; |
| else if (greturn *return_stmt = dyn_cast <greturn *> (stmt)) |
| { |
| found_return = true; |
| retval = gimple_return_retval (return_stmt); |
| } |
| /* For -fsanitize=thread, allow also TSAN_FUNC_EXIT () in the return |
| bb. */ |
| else if ((flag_sanitize & SANITIZE_THREAD) |
| && gimple_call_internal_p (stmt, IFN_TSAN_FUNC_EXIT)) |
| ; |
| else |
| break; |
| } |
| if (gsi_end_p (bsi) && found_return) |
| return_bb = e->src; |
| |
| return return_bb; |
| } |
| |
| /* Given return basic block RETURN_BB, see where return value is really |
| stored. */ |
| static tree |
| find_retval (basic_block return_bb) |
| { |
| gimple_stmt_iterator bsi; |
| for (bsi = gsi_start_bb (return_bb); !gsi_end_p (bsi); gsi_next (&bsi)) |
| if (greturn *return_stmt = dyn_cast <greturn *> (gsi_stmt (bsi))) |
| return gimple_return_retval (return_stmt); |
| else if (gimple_code (gsi_stmt (bsi)) == GIMPLE_ASSIGN |
| && !gimple_clobber_p (gsi_stmt (bsi))) |
| return gimple_assign_rhs1 (gsi_stmt (bsi)); |
| return NULL; |
| } |
| |
| /* Given return basic block RETURN_BB, see where return bounds are really |
| stored. */ |
| static tree |
| find_retbnd (basic_block return_bb) |
| { |
| gimple_stmt_iterator bsi; |
| for (bsi = gsi_last_bb (return_bb); !gsi_end_p (bsi); gsi_prev (&bsi)) |
| if (gimple_code (gsi_stmt (bsi)) == GIMPLE_RETURN) |
| return gimple_return_retbnd (gsi_stmt (bsi)); |
| return NULL; |
| } |
| |
| /* Callback for walk_stmt_load_store_addr_ops. If T is non-SSA automatic |
| variable, mark it as used in bitmap passed via DATA. |
| Return true when access to T prevents splitting the function. */ |
| |
| static bool |
| mark_nonssa_use (gimple *, tree t, tree, void *data) |
| { |
| t = get_base_address (t); |
| |
| if (!t || is_gimple_reg (t)) |
| return false; |
| |
| /* At present we can't pass non-SSA arguments to split function. |
| FIXME: this can be relaxed by passing references to arguments. */ |
| if (TREE_CODE (t) == PARM_DECL) |
| { |
| if (dump_file && (dump_flags & TDF_DETAILS)) |
| fprintf (dump_file, |
| "Cannot split: use of non-ssa function parameter.\n"); |
| return true; |
| } |
| |
| if ((VAR_P (t) && auto_var_in_fn_p (t, current_function_decl)) |
| || TREE_CODE (t) == RESULT_DECL |
| || (TREE_CODE (t) == LABEL_DECL && FORCED_LABEL (t))) |
| bitmap_set_bit ((bitmap)data, DECL_UID (t)); |
| |
| /* For DECL_BY_REFERENCE, the return value is actually a pointer. We want |
| to pretend that the value pointed to is actual result decl. */ |
| if ((TREE_CODE (t) == MEM_REF || INDIRECT_REF_P (t)) |
| && TREE_CODE (TREE_OPERAND (t, 0)) == SSA_NAME |
| && SSA_NAME_VAR (TREE_OPERAND (t, 0)) |
| && TREE_CODE (SSA_NAME_VAR (TREE_OPERAND (t, 0))) == RESULT_DECL |
| && DECL_BY_REFERENCE (DECL_RESULT (current_function_decl))) |
| return |
| bitmap_bit_p ((bitmap)data, |
| DECL_UID (DECL_RESULT (current_function_decl))); |
| |
| return false; |
| } |
| |
| /* Compute local properties of basic block BB we collect when looking for |
| split points. We look for ssa defs and store them in SET_SSA_NAMES, |
| for ssa uses and store them in USED_SSA_NAMES and for any non-SSA automatic |
| vars stored in NON_SSA_VARS. |
| |
| When BB has edge to RETURN_BB, collect uses in RETURN_BB too. |
| |
| Return false when BB contains something that prevents it from being put into |
| split function. */ |
| |
| static bool |
| visit_bb (basic_block bb, basic_block return_bb, |
| bitmap set_ssa_names, bitmap used_ssa_names, |
| bitmap non_ssa_vars) |
| { |
| edge e; |
| edge_iterator ei; |
| bool can_split = true; |
| |
| for (gimple_stmt_iterator bsi = gsi_start_bb (bb); !gsi_end_p (bsi); |
| gsi_next (&bsi)) |
| { |
| gimple *stmt = gsi_stmt (bsi); |
| tree op; |
| ssa_op_iter iter; |
| tree decl; |
| |
| if (is_gimple_debug (stmt)) |
| continue; |
| |
| if (gimple_clobber_p (stmt)) |
| continue; |
| |
| /* FIXME: We can split regions containing EH. We can not however |
| split RESX, EH_DISPATCH and EH_POINTER referring to same region |
| into different partitions. This would require tracking of |
| EH regions and checking in consider_split_point if they |
| are not used elsewhere. */ |
| if (gimple_code (stmt) == GIMPLE_RESX) |
| { |
| if (dump_file && (dump_flags & TDF_DETAILS)) |
| fprintf (dump_file, "Cannot split: resx.\n"); |
| can_split = false; |
| } |
| if (gimple_code (stmt) == GIMPLE_EH_DISPATCH) |
| { |
| if (dump_file && (dump_flags & TDF_DETAILS)) |
| fprintf (dump_file, "Cannot split: eh dispatch.\n"); |
| can_split = false; |
| } |
| |
| /* Check builtins that prevent splitting. */ |
| if (gimple_code (stmt) == GIMPLE_CALL |
| && (decl = gimple_call_fndecl (stmt)) != NULL_TREE |
| && DECL_BUILT_IN (decl) |
| && DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL) |
| switch (DECL_FUNCTION_CODE (decl)) |
| { |
| /* FIXME: once we will allow passing non-parm values to split part, |
| we need to be sure to handle correct builtin_stack_save and |
| builtin_stack_restore. At the moment we are safe; there is no |
| way to store builtin_stack_save result in non-SSA variable |
| since all calls to those are compiler generated. */ |
| case BUILT_IN_APPLY: |
| case BUILT_IN_APPLY_ARGS: |
| case BUILT_IN_VA_START: |
| if (dump_file && (dump_flags & TDF_DETAILS)) |
| fprintf (dump_file, |
| "Cannot split: builtin_apply and va_start.\n"); |
| can_split = false; |
| break; |
| case BUILT_IN_EH_POINTER: |
| if (dump_file && (dump_flags & TDF_DETAILS)) |
| fprintf (dump_file, "Cannot split: builtin_eh_pointer.\n"); |
| can_split = false; |
| break; |
| default: |
| break; |
| } |
| |
| FOR_EACH_SSA_TREE_OPERAND (op, stmt, iter, SSA_OP_DEF) |
| bitmap_set_bit (set_ssa_names, SSA_NAME_VERSION (op)); |
| FOR_EACH_SSA_TREE_OPERAND (op, stmt, iter, SSA_OP_USE) |
| bitmap_set_bit (used_ssa_names, SSA_NAME_VERSION (op)); |
| can_split &= !walk_stmt_load_store_addr_ops (stmt, non_ssa_vars, |
| mark_nonssa_use, |
| mark_nonssa_use, |
| mark_nonssa_use); |
| } |
| for (gphi_iterator bsi = gsi_start_phis (bb); !gsi_end_p (bsi); |
| gsi_next (&bsi)) |
| { |
| gphi *stmt = bsi.phi (); |
| unsigned int i; |
| |
| if (virtual_operand_p (gimple_phi_result (stmt))) |
| continue; |
| bitmap_set_bit (set_ssa_names, |
| SSA_NAME_VERSION (gimple_phi_result (stmt))); |
| for (i = 0; i < gimple_phi_num_args (stmt); i++) |
| { |
| tree op = gimple_phi_arg_def (stmt, i); |
| if (TREE_CODE (op) == SSA_NAME) |
| bitmap_set_bit (used_ssa_names, SSA_NAME_VERSION (op)); |
| } |
| can_split &= !walk_stmt_load_store_addr_ops (stmt, non_ssa_vars, |
| mark_nonssa_use, |
| mark_nonssa_use, |
| mark_nonssa_use); |
| } |
| /* Record also uses coming from PHI operand in return BB. */ |
| FOR_EACH_EDGE (e, ei, bb->succs) |
| if (e->dest == return_bb) |
| { |
| for (gphi_iterator bsi = gsi_start_phis (return_bb); |
| !gsi_end_p (bsi); |
| gsi_next (&bsi)) |
| { |
| gphi *stmt = bsi.phi (); |
| tree op = gimple_phi_arg_def (stmt, e->dest_idx); |
| |
| if (virtual_operand_p (gimple_phi_result (stmt))) |
| continue; |
| if (TREE_CODE (op) == SSA_NAME) |
| bitmap_set_bit (used_ssa_names, SSA_NAME_VERSION (op)); |
| else |
| can_split &= !mark_nonssa_use (stmt, op, op, non_ssa_vars); |
| } |
| } |
| return can_split; |
| } |
| |
| /* Stack entry for recursive DFS walk in find_split_point. */ |
| |
| struct stack_entry |
| { |
| /* Basic block we are examining. */ |
| basic_block bb; |
| |
| /* SSA names set and used by the BB and all BBs reachable |
| from it via DFS walk. */ |
| bitmap set_ssa_names, used_ssa_names; |
| bitmap non_ssa_vars; |
| |
| /* All BBS visited from this BB via DFS walk. */ |
| bitmap bbs_visited; |
| |
| /* Last examined edge in DFS walk. Since we walk unoriented graph, |
| the value is up to sum of incoming and outgoing edges of BB. */ |
| unsigned int edge_num; |
| |
| /* Stack entry index of earliest BB reachable from current BB |
| or any BB visited later in DFS walk. */ |
| int earliest; |
| |
| /* Overall time and size of all BBs reached from this BB in DFS walk. */ |
| int overall_time, overall_size; |
| |
| /* When false we can not split on this BB. */ |
| bool can_split; |
| }; |
| |
| |
| /* Find all articulations and call consider_split on them. |
| OVERALL_TIME and OVERALL_SIZE is time and size of the function. |
| |
| We perform basic algorithm for finding an articulation in a graph |
| created from CFG by considering it to be an unoriented graph. |
| |
| The articulation is discovered via DFS walk. We collect earliest |
| basic block on stack that is reachable via backward edge. Articulation |
| is any basic block such that there is no backward edge bypassing it. |
| To reduce stack usage we maintain heap allocated stack in STACK vector. |
| AUX pointer of BB is set to index it appears in the stack or -1 once |
| it is visited and popped off the stack. |
| |
| The algorithm finds articulation after visiting the whole component |
| reachable by it. This makes it convenient to collect information about |
| the component used by consider_split. */ |
| |
| static void |
| find_split_points (basic_block return_bb, int overall_time, int overall_size) |
| { |
| stack_entry first; |
| vec<stack_entry> stack = vNULL; |
| basic_block bb; |
| struct split_point current; |
| |
| current.header_time = overall_time; |
| current.header_size = overall_size; |
| current.split_time = 0; |
| current.split_size = 0; |
| current.ssa_names_to_pass = BITMAP_ALLOC (NULL); |
| |
| first.bb = ENTRY_BLOCK_PTR_FOR_FN (cfun); |
| first.edge_num = 0; |
| first.overall_time = 0; |
| first.overall_size = 0; |
| first.earliest = INT_MAX; |
| first.set_ssa_names = 0; |
| first.used_ssa_names = 0; |
| first.non_ssa_vars = 0; |
| first.bbs_visited = 0; |
| first.can_split = false; |
| stack.safe_push (first); |
| ENTRY_BLOCK_PTR_FOR_FN (cfun)->aux = (void *)(intptr_t)-1; |
| |
| while (!stack.is_empty ()) |
| { |
| stack_entry *entry = &stack.last (); |
| |
| /* We are walking an acyclic graph, so edge_num counts |
| succ and pred edges together. However when considering |
| articulation, we want to have processed everything reachable |
| from articulation but nothing that reaches into it. */ |
| if (entry->edge_num == EDGE_COUNT (entry->bb->succs) |
| && entry->bb != ENTRY_BLOCK_PTR_FOR_FN (cfun)) |
| { |
| int pos = stack.length (); |
| entry->can_split &= visit_bb (entry->bb, return_bb, |
| entry->set_ssa_names, |
| entry->used_ssa_names, |
| entry->non_ssa_vars); |
| if (pos <= entry->earliest && !entry->can_split |
| && dump_file && (dump_flags & TDF_DETAILS)) |
| fprintf (dump_file, |
| "found articulation at bb %i but can not split\n", |
| entry->bb->index); |
| if (pos <= entry->earliest && entry->can_split) |
| { |
| if (dump_file && (dump_flags & TDF_DETAILS)) |
| fprintf (dump_file, "found articulation at bb %i\n", |
| entry->bb->index); |
| current.entry_bb = entry->bb; |
| current.ssa_names_to_pass = BITMAP_ALLOC (NULL); |
| bitmap_and_compl (current.ssa_names_to_pass, |
| entry->used_ssa_names, entry->set_ssa_names); |
| current.header_time = overall_time - entry->overall_time; |
| current.header_size = overall_size - entry->overall_size; |
| current.split_time = entry->overall_time; |
| current.split_size = entry->overall_size; |
| current.split_bbs = entry->bbs_visited; |
| consider_split (¤t, entry->non_ssa_vars, return_bb); |
| BITMAP_FREE (current.ssa_names_to_pass); |
| } |
| } |
| /* Do actual DFS walk. */ |
| if (entry->edge_num |
| < (EDGE_COUNT (entry->bb->succs) |
| + EDGE_COUNT (entry->bb->preds))) |
| { |
| edge e; |
| basic_block dest; |
| if (entry->edge_num < EDGE_COUNT (entry->bb->succs)) |
| { |
| e = EDGE_SUCC (entry->bb, entry->edge_num); |
| dest = e->dest; |
| } |
| else |
| { |
| e = EDGE_PRED (entry->bb, entry->edge_num |
| - EDGE_COUNT (entry->bb->succs)); |
| dest = e->src; |
| } |
| |
| entry->edge_num++; |
| |
| /* New BB to visit, push it to the stack. */ |
| if (dest != return_bb && dest != EXIT_BLOCK_PTR_FOR_FN (cfun) |
| && !dest->aux) |
| { |
| stack_entry new_entry; |
| |
| new_entry.bb = dest; |
| new_entry.edge_num = 0; |
| new_entry.overall_time |
| = bb_info_vec[dest->index].time; |
| new_entry.overall_size |
| = bb_info_vec[dest->index].size; |
| new_entry.earliest = INT_MAX; |
| new_entry.set_ssa_names = BITMAP_ALLOC (NULL); |
| new_entry.used_ssa_names = BITMAP_ALLOC (NULL); |
| new_entry.bbs_visited = BITMAP_ALLOC (NULL); |
| new_entry.non_ssa_vars = BITMAP_ALLOC (NULL); |
| new_entry.can_split = true; |
| bitmap_set_bit (new_entry.bbs_visited, dest->index); |
| stack.safe_push (new_entry); |
| dest->aux = (void *)(intptr_t)stack.length (); |
| } |
| /* Back edge found, record the earliest point. */ |
| else if ((intptr_t)dest->aux > 0 |
| && (intptr_t)dest->aux < entry->earliest) |
| entry->earliest = (intptr_t)dest->aux; |
| } |
| /* We are done with examining the edges. Pop off the value from stack |
| and merge stuff we accumulate during the walk. */ |
| else if (entry->bb != ENTRY_BLOCK_PTR_FOR_FN (cfun)) |
| { |
| stack_entry *prev = &stack[stack.length () - 2]; |
| |
| entry->bb->aux = (void *)(intptr_t)-1; |
| prev->can_split &= entry->can_split; |
| if (prev->set_ssa_names) |
| { |
| bitmap_ior_into (prev->set_ssa_names, entry->set_ssa_names); |
| bitmap_ior_into (prev->used_ssa_names, entry->used_ssa_names); |
| bitmap_ior_into (prev->bbs_visited, entry->bbs_visited); |
| bitmap_ior_into (prev->non_ssa_vars, entry->non_ssa_vars); |
| } |
| if (prev->earliest > entry->earliest) |
| prev->earliest = entry->earliest; |
| prev->overall_time += entry->overall_time; |
| prev->overall_size += entry->overall_size; |
| BITMAP_FREE (entry->set_ssa_names); |
| BITMAP_FREE (entry->used_ssa_names); |
| BITMAP_FREE (entry->bbs_visited); |
| BITMAP_FREE (entry->non_ssa_vars); |
| stack.pop (); |
| } |
| else |
| stack.pop (); |
| } |
| ENTRY_BLOCK_PTR_FOR_FN (cfun)->aux = NULL; |
| FOR_EACH_BB_FN (bb, cfun) |
| bb->aux = NULL; |
| stack.release (); |
| BITMAP_FREE (current.ssa_names_to_pass); |
| } |
| |
| /* Split function at SPLIT_POINT. */ |
| |
| static void |
| split_function (basic_block return_bb, struct split_point *split_point, |
| bool add_tsan_func_exit) |
| { |
| vec<tree> args_to_pass = vNULL; |
| bitmap args_to_skip; |
| tree parm; |
| int num = 0; |
| cgraph_node *node, *cur_node = cgraph_node::get (current_function_decl); |
| basic_block call_bb; |
| gcall *call, *tsan_func_exit_call = NULL; |
| edge e; |
| edge_iterator ei; |
| tree retval = NULL, real_retval = NULL, retbnd = NULL; |
| bool with_bounds = chkp_function_instrumented_p (current_function_decl); |
| gimple *last_stmt = NULL; |
| unsigned int i; |
| tree arg, ddef; |
| |
| if (dump_file) |
| { |
| fprintf (dump_file, "\n\nSplitting function at:\n"); |
| dump_split_point (dump_file, split_point); |
| } |
| |
| if (cur_node->local.can_change_signature) |
| args_to_skip = BITMAP_ALLOC (NULL); |
| else |
| args_to_skip = NULL; |
| |
| /* Collect the parameters of new function and args_to_skip bitmap. */ |
| for (parm = DECL_ARGUMENTS (current_function_decl); |
| parm; parm = DECL_CHAIN (parm), num++) |
| if (args_to_skip |
| && (!is_gimple_reg (parm) |
| || (ddef = ssa_default_def (cfun, parm)) == NULL_TREE |
| || !bitmap_bit_p (split_point->ssa_names_to_pass, |
| SSA_NAME_VERSION (ddef)))) |
| bitmap_set_bit (args_to_skip, num); |
| else |
| { |
| /* This parm might not have been used up to now, but is going to be |
| used, hence register it. */ |
| if (is_gimple_reg (parm)) |
| arg = get_or_create_ssa_default_def (cfun, parm); |
| else |
| arg = parm; |
| |
| if (!useless_type_conversion_p (DECL_ARG_TYPE (parm), TREE_TYPE (arg))) |
| arg = fold_convert (DECL_ARG_TYPE (parm), arg); |
| args_to_pass.safe_push (arg); |
| } |
| |
| /* See if the split function will return. */ |
| bool split_part_return_p = false; |
| FOR_EACH_EDGE (e, ei, return_bb->preds) |
| { |
| if (bitmap_bit_p (split_point->split_bbs, e->src->index)) |
| split_part_return_p = true; |
| } |
| |
| /* Add return block to what will become the split function. |
| We do not return; no return block is needed. */ |
| if (!split_part_return_p) |
| ; |
| /* We have no return block, so nothing is needed. */ |
| else if (return_bb == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
| ; |
| /* When we do not want to return value, we need to construct |
| new return block with empty return statement. |
| FIXME: Once we are able to change return type, we should change function |
| to return void instead of just outputting function with undefined return |
| value. For structures this affects quality of codegen. */ |
| else if ((retval = find_retval (return_bb)) |
| && !split_point->split_part_set_retval) |
| { |
| bool redirected = true; |
| basic_block new_return_bb = create_basic_block (NULL, 0, return_bb); |
| gimple_stmt_iterator gsi = gsi_start_bb (new_return_bb); |
| gsi_insert_after (&gsi, gimple_build_return (NULL), GSI_NEW_STMT); |
| while (redirected) |
| { |
| redirected = false; |
| FOR_EACH_EDGE (e, ei, return_bb->preds) |
| if (bitmap_bit_p (split_point->split_bbs, e->src->index)) |
| { |
| new_return_bb->count += e->count; |
| new_return_bb->frequency += EDGE_FREQUENCY (e); |
| redirect_edge_and_branch (e, new_return_bb); |
| redirected = true; |
| break; |
| } |
| } |
| e = make_edge (new_return_bb, EXIT_BLOCK_PTR_FOR_FN (cfun), 0); |
| e->probability = REG_BR_PROB_BASE; |
| e->count = new_return_bb->count; |
| add_bb_to_loop (new_return_bb, current_loops->tree_root); |
| bitmap_set_bit (split_point->split_bbs, new_return_bb->index); |
| retbnd = find_retbnd (return_bb); |
| } |
| /* When we pass around the value, use existing return block. */ |
| else |
| { |
| bitmap_set_bit (split_point->split_bbs, return_bb->index); |
| retbnd = find_retbnd (return_bb); |
| } |
| |
| /* If RETURN_BB has virtual operand PHIs, they must be removed and the |
| virtual operand marked for renaming as we change the CFG in a way that |
| tree-inline is not able to compensate for. |
| |
| Note this can happen whether or not we have a return value. If we have |
| a return value, then RETURN_BB may have PHIs for real operands too. */ |
| if (return_bb != EXIT_BLOCK_PTR_FOR_FN (cfun)) |
| { |
| bool phi_p = false; |
| for (gphi_iterator gsi = gsi_start_phis (return_bb); |
| !gsi_end_p (gsi);) |
| { |
| gphi *stmt = gsi.phi (); |
| if (!virtual_operand_p (gimple_phi_result (stmt))) |
| { |
| gsi_next (&gsi); |
| continue; |
| } |
| mark_virtual_phi_result_for_renaming (stmt); |
| remove_phi_node (&gsi, true); |
| phi_p = true; |
| } |
| /* In reality we have to rename the reaching definition of the |
| virtual operand at return_bb as we will eventually release it |
| when we remove the code region we outlined. |
| So we have to rename all immediate virtual uses of that region |
| if we didn't see a PHI definition yet. */ |
| /* ??? In real reality we want to set the reaching vdef of the |
| entry of the SESE region as the vuse of the call and the reaching |
| vdef of the exit of the SESE region as the vdef of the call. */ |
| if (!phi_p) |
| for (gimple_stmt_iterator gsi = gsi_start_bb (return_bb); |
| !gsi_end_p (gsi); |
| gsi_next (&gsi)) |
| { |
| gimple *stmt = gsi_stmt (gsi); |
| if (gimple_vuse (stmt)) |
| { |
| gimple_set_vuse (stmt, NULL_TREE); |
| update_stmt (stmt); |
| } |
| if (gimple_vdef (stmt)) |
| break; |
| } |
| } |
| |
| /* Now create the actual clone. */ |
| cgraph_edge::rebuild_edges (); |
| node = cur_node->create_version_clone_with_body |
| (vNULL, NULL, args_to_skip, |
| !split_part_return_p || !split_point->split_part_set_retval, |
| split_point->split_bbs, split_point->entry_bb, "part"); |
| |
| node->split_part = true; |
| |
| if (cur_node->same_comdat_group) |
| { |
| /* TODO: call is versionable if we make sure that all |
| callers are inside of a comdat group. */ |
| cur_node->calls_comdat_local = 1; |
| node->add_to_same_comdat_group (cur_node); |
| } |
| |
| |
| /* Let's take a time profile for splitted function. */ |
| node->tp_first_run = cur_node->tp_first_run + 1; |
| |
| /* For usual cloning it is enough to clear builtin only when signature |
| changes. For partial inlining we however can not expect the part |
| of builtin implementation to have same semantic as the whole. */ |
| if (DECL_BUILT_IN (node->decl)) |
| { |
| DECL_BUILT_IN_CLASS (node->decl) = NOT_BUILT_IN; |
| DECL_FUNCTION_CODE (node->decl) = (enum built_in_function) 0; |
| } |
| |
| /* If return_bb contains any clobbers that refer to SSA_NAMEs |
| set in the split part, remove them. Also reset debug stmts that |
| refer to SSA_NAMEs set in the split part. */ |
| if (return_bb != EXIT_BLOCK_PTR_FOR_FN (cfun)) |
| { |
| gimple_stmt_iterator gsi = gsi_start_bb (return_bb); |
| while (!gsi_end_p (gsi)) |
| { |
| tree op; |
| ssa_op_iter iter; |
| gimple *stmt = gsi_stmt (gsi); |
| bool remove = false; |
| if (gimple_clobber_p (stmt) || is_gimple_debug (stmt)) |
| FOR_EACH_SSA_TREE_OPERAND (op, stmt, iter, SSA_OP_USE) |
| { |
| basic_block bb = gimple_bb (SSA_NAME_DEF_STMT (op)); |
| if (op != retval |
| && bb |
| && bb != return_bb |
| && bitmap_bit_p (split_point->split_bbs, bb->index)) |
| { |
| if (is_gimple_debug (stmt)) |
| { |
| gimple_debug_bind_reset_value (stmt); |
| update_stmt (stmt); |
| } |
| else |
| remove = true; |
| break; |
| } |
| } |
| if (remove) |
| gsi_remove (&gsi, true); |
| else |
| gsi_next (&gsi); |
| } |
| } |
| |
| /* If the original function is instrumented then it's |
| part is also instrumented. */ |
| if (with_bounds) |
| chkp_function_mark_instrumented (node->decl); |
| |
| /* If the original function is declared inline, there is no point in issuing |
| a warning for the non-inlinable part. */ |
| DECL_NO_INLINE_WARNING_P (node->decl) = 1; |
| cur_node->remove_callees (); |
| cur_node->remove_all_references (); |
| if (!split_part_return_p) |
| TREE_THIS_VOLATILE (node->decl) = 1; |
| if (dump_file) |
| dump_function_to_file (node->decl, dump_file, dump_flags); |
| |
| /* Create the basic block we place call into. It is the entry basic block |
| split after last label. */ |
| call_bb = split_point->entry_bb; |
| for (gimple_stmt_iterator gsi = gsi_start_bb (call_bb); !gsi_end_p (gsi);) |
| if (gimple_code (gsi_stmt (gsi)) == GIMPLE_LABEL) |
| { |
| last_stmt = gsi_stmt (gsi); |
| gsi_next (&gsi); |
| } |
| else |
| break; |
| e = split_block (split_point->entry_bb, last_stmt); |
| remove_edge (e); |
| |
| /* Produce the call statement. */ |
| gimple_stmt_iterator gsi = gsi_last_bb (call_bb); |
| FOR_EACH_VEC_ELT (args_to_pass, i, arg) |
| if (!is_gimple_val (arg)) |
| { |
| arg = force_gimple_operand_gsi (&gsi, arg, true, NULL_TREE, |
| false, GSI_CONTINUE_LINKING); |
| args_to_pass[i] = arg; |
| } |
| call = gimple_build_call_vec (node->decl, args_to_pass); |
| gimple_call_set_with_bounds (call, with_bounds); |
| gimple_set_block (call, DECL_INITIAL (current_function_decl)); |
| args_to_pass.release (); |
| |
| /* For optimized away parameters, add on the caller side |
| before the call |
| DEBUG D#X => parm_Y(D) |
| stmts and associate D#X with parm in decl_debug_args_lookup |
| vector to say for debug info that if parameter parm had been passed, |
| it would have value parm_Y(D). */ |
| if (args_to_skip) |
| { |
| vec<tree, va_gc> **debug_args = NULL; |
| unsigned i = 0, len = 0; |
| if (MAY_HAVE_DEBUG_STMTS) |
| { |
| debug_args = decl_debug_args_lookup (node->decl); |
| if (debug_args) |
| len = vec_safe_length (*debug_args); |
| } |
| for (parm = DECL_ARGUMENTS (current_function_decl), num = 0; |
| parm; parm = DECL_CHAIN (parm), num++) |
| if (bitmap_bit_p (args_to_skip, num) && is_gimple_reg (parm)) |
| { |
| tree ddecl; |
| gimple *def_temp; |
| |
| /* This needs to be done even without MAY_HAVE_DEBUG_STMTS, |
| otherwise if it didn't exist before, we'd end up with |
| different SSA_NAME_VERSIONs between -g and -g0. */ |
| arg = get_or_create_ssa_default_def (cfun, parm); |
| if (!MAY_HAVE_DEBUG_STMTS || debug_args == NULL) |
| continue; |
| |
| while (i < len && (**debug_args)[i] != DECL_ORIGIN (parm)) |
| i += 2; |
| if (i >= len) |
| continue; |
| ddecl = (**debug_args)[i + 1]; |
| def_temp |
| = gimple_build_debug_bind (ddecl, unshare_expr (arg), call); |
| gsi_insert_after (&gsi, def_temp, GSI_NEW_STMT); |
| } |
| } |
| |
| /* We avoid address being taken on any variable used by split part, |
| so return slot optimization is always possible. Moreover this is |
| required to make DECL_BY_REFERENCE work. */ |
| if (aggregate_value_p (DECL_RESULT (current_function_decl), |
| TREE_TYPE (current_function_decl)) |
| && (!is_gimple_reg_type (TREE_TYPE (DECL_RESULT (current_function_decl))) |
| || DECL_BY_REFERENCE (DECL_RESULT (current_function_decl)))) |
| gimple_call_set_return_slot_opt (call, true); |
| |
| if (add_tsan_func_exit) |
| tsan_func_exit_call = gimple_build_call_internal (IFN_TSAN_FUNC_EXIT, 0); |
| |
| /* Update return value. This is bit tricky. When we do not return, |
| do nothing. When we return we might need to update return_bb |
| or produce a new return statement. */ |
| if (!split_part_return_p) |
| { |
| gsi_insert_after (&gsi, call, GSI_NEW_STMT); |
| if (tsan_func_exit_call) |
| gsi_insert_after (&gsi, tsan_func_exit_call, GSI_NEW_STMT); |
| } |
| else |
| { |
| e = make_edge (call_bb, return_bb, |
| return_bb == EXIT_BLOCK_PTR_FOR_FN (cfun) |
| ? 0 : EDGE_FALLTHRU); |
| e->count = call_bb->count; |
| e->probability = REG_BR_PROB_BASE; |
| |
| /* If there is return basic block, see what value we need to store |
| return value into and put call just before it. */ |
| if (return_bb != EXIT_BLOCK_PTR_FOR_FN (cfun)) |
| { |
| real_retval = retval; |
| if (real_retval && split_point->split_part_set_retval) |
| { |
| gphi_iterator psi; |
| |
| /* See if we need new SSA_NAME for the result. |
| When DECL_BY_REFERENCE is true, retval is actually pointer to |
| return value and it is constant in whole function. */ |
| if (TREE_CODE (retval) == SSA_NAME |
| && !DECL_BY_REFERENCE (DECL_RESULT (current_function_decl))) |
| { |
| retval = copy_ssa_name (retval, call); |
| |
| /* See if there is PHI defining return value. */ |
| for (psi = gsi_start_phis (return_bb); |
| !gsi_end_p (psi); gsi_next (&psi)) |
| if (!virtual_operand_p (gimple_phi_result (psi.phi ()))) |
| break; |
| |
| /* When there is PHI, just update its value. */ |
| if (TREE_CODE (retval) == SSA_NAME |
| && !gsi_end_p (psi)) |
| add_phi_arg (psi.phi (), retval, e, UNKNOWN_LOCATION); |
| /* Otherwise update the return BB itself. |
| find_return_bb allows at most one assignment to return value, |
| so update first statement. */ |
| else |
| { |
| gimple_stmt_iterator bsi; |
| for (bsi = gsi_start_bb (return_bb); !gsi_end_p (bsi); |
| gsi_next (&bsi)) |
| if (greturn *return_stmt |
| = dyn_cast <greturn *> (gsi_stmt (bsi))) |
| { |
| gimple_return_set_retval (return_stmt, retval); |
| break; |
| } |
| else if (gimple_code (gsi_stmt (bsi)) == GIMPLE_ASSIGN |
| && !gimple_clobber_p (gsi_stmt (bsi))) |
| { |
| gimple_assign_set_rhs1 (gsi_stmt (bsi), retval); |
| break; |
| } |
| update_stmt (gsi_stmt (bsi)); |
| /* Also adjust clobbers and debug stmts in return_bb. */ |
| for (bsi = gsi_start_bb (return_bb); !gsi_end_p (bsi); |
| gsi_next (&bsi)) |
| { |
| gimple *stmt = gsi_stmt (bsi); |
| if (gimple_clobber_p (stmt) |
| || is_gimple_debug (stmt)) |
| { |
| ssa_op_iter iter; |
| use_operand_p use_p; |
| bool update = false; |
| FOR_EACH_SSA_USE_OPERAND (use_p, stmt, iter, |
| SSA_OP_USE) |
| if (USE_FROM_PTR (use_p) == real_retval) |
| { |
| SET_USE (use_p, retval); |
| update = true; |
| } |
| if (update) |
| update_stmt (stmt); |
| } |
| } |
| } |
| |
| /* Replace retbnd with new one. */ |
| if (retbnd) |
| { |
| gimple_stmt_iterator bsi; |
| for (bsi = gsi_last_bb (return_bb); !gsi_end_p (bsi); |
| gsi_prev (&bsi)) |
| if (gimple_code (gsi_stmt (bsi)) == GIMPLE_RETURN) |
| { |
| retbnd = copy_ssa_name (retbnd, call); |
| gimple_return_set_retbnd (gsi_stmt (bsi), retbnd); |
| update_stmt (gsi_stmt (bsi)); |
| break; |
| } |
| } |
| } |
| if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl))) |
| { |
| gimple_call_set_lhs (call, build_simple_mem_ref (retval)); |
| gsi_insert_after (&gsi, call, GSI_NEW_STMT); |
| } |
| else |
| { |
| tree restype; |
| restype = TREE_TYPE (DECL_RESULT (current_function_decl)); |
| gsi_insert_after (&gsi, call, GSI_NEW_STMT); |
| if (!useless_type_conversion_p (TREE_TYPE (retval), restype)) |
| { |
| gimple *cpy; |
| tree tem = create_tmp_reg (restype); |
| tem = make_ssa_name (tem, call); |
| cpy = gimple_build_assign (retval, NOP_EXPR, tem); |
| gsi_insert_after (&gsi, cpy, GSI_NEW_STMT); |
| retval = tem; |
| } |
| /* Build bndret call to obtain returned bounds. */ |
| if (retbnd) |
| chkp_insert_retbnd_call (retbnd, retval, &gsi); |
| gimple_call_set_lhs (call, retval); |
| update_stmt (call); |
| } |
| } |
| else |
| gsi_insert_after (&gsi, call, GSI_NEW_STMT); |
| if (tsan_func_exit_call) |
| gsi_insert_after (&gsi, tsan_func_exit_call, GSI_NEW_STMT); |
| } |
| /* We don't use return block (there is either no return in function or |
| multiple of them). So create new basic block with return statement. |
| */ |
| else |
| { |
| greturn *ret; |
| if (split_point->split_part_set_retval |
| && !VOID_TYPE_P (TREE_TYPE (TREE_TYPE (current_function_decl)))) |
| { |
| retval = DECL_RESULT (current_function_decl); |
| |
| if (chkp_function_instrumented_p (current_function_decl) |
| && BOUNDED_P (retval)) |
| retbnd = create_tmp_reg (pointer_bounds_type_node); |
| |
| /* We use temporary register to hold value when aggregate_value_p |
| is false. Similarly for DECL_BY_REFERENCE we must avoid extra |
| copy. */ |
| if (!aggregate_value_p (retval, TREE_TYPE (current_function_decl)) |
| && !DECL_BY_REFERENCE (retval)) |
| retval = create_tmp_reg (TREE_TYPE (retval)); |
| if (is_gimple_reg (retval)) |
| { |
| /* When returning by reference, there is only one SSA name |
| assigned to RESULT_DECL (that is pointer to return value). |
| Look it up or create new one if it is missing. */ |
| if (DECL_BY_REFERENCE (retval)) |
| retval = get_or_create_ssa_default_def (cfun, retval); |
| /* Otherwise produce new SSA name for return value. */ |
| else |
| retval = make_ssa_name (retval, call); |
| } |
| if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl))) |
| gimple_call_set_lhs (call, build_simple_mem_ref (retval)); |
| else |
| gimple_call_set_lhs (call, retval); |
| gsi_insert_after (&gsi, call, GSI_NEW_STMT); |
| } |
| else |
| { |
| gsi_insert_after (&gsi, call, GSI_NEW_STMT); |
| if (retval |
| && is_gimple_reg_type (TREE_TYPE (retval)) |
| && !is_gimple_val (retval)) |
| { |
| gassign *g |
| = gimple_build_assign (make_ssa_name (TREE_TYPE (retval)), |
| retval); |
| retval = gimple_assign_lhs (g); |
| gsi_insert_after (&gsi, g, GSI_NEW_STMT); |
| } |
| } |
| /* Build bndret call to obtain returned bounds. */ |
| if (retbnd) |
| chkp_insert_retbnd_call (retbnd, retval, &gsi); |
| if (tsan_func_exit_call) |
| gsi_insert_after (&gsi, tsan_func_exit_call, GSI_NEW_STMT); |
| ret = gimple_build_return (retval); |
| gsi_insert_after (&gsi, ret, GSI_NEW_STMT); |
| } |
| } |
| free_dominance_info (CDI_DOMINATORS); |
| free_dominance_info (CDI_POST_DOMINATORS); |
| compute_inline_parameters (node, true); |
| } |
| |
| /* Execute function splitting pass. */ |
| |
| static unsigned int |
| execute_split_functions (void) |
| { |
| gimple_stmt_iterator bsi; |
| basic_block bb; |
| int overall_time = 0, overall_size = 0; |
| int todo = 0; |
| struct cgraph_node *node = cgraph_node::get (current_function_decl); |
| |
| if (flags_from_decl_or_type (current_function_decl) |
| & (ECF_NORETURN|ECF_MALLOC)) |
| { |
| if (dump_file) |
| fprintf (dump_file, "Not splitting: noreturn/malloc function.\n"); |
| return 0; |
| } |
| if (MAIN_NAME_P (DECL_NAME (current_function_decl))) |
| { |
| if (dump_file) |
| fprintf (dump_file, "Not splitting: main function.\n"); |
| return 0; |
| } |
| /* This can be relaxed; function might become inlinable after splitting |
| away the uninlinable part. */ |
| if (inline_edge_summary_vec.exists () |
| && !inline_summaries->get (node)->inlinable) |
| { |
| if (dump_file) |
| fprintf (dump_file, "Not splitting: not inlinable.\n"); |
| return 0; |
| } |
| if (DECL_DISREGARD_INLINE_LIMITS (node->decl)) |
| { |
| if (dump_file) |
| fprintf (dump_file, "Not splitting: disregarding inline limits.\n"); |
| return 0; |
| } |
| /* This can be relaxed; most of versioning tests actually prevents |
| a duplication. */ |
| if (!tree_versionable_function_p (current_function_decl)) |
| { |
| if (dump_file) |
| fprintf (dump_file, "Not splitting: not versionable.\n"); |
| return 0; |
| } |
| /* FIXME: we could support this. */ |
| if (DECL_STRUCT_FUNCTION (current_function_decl)->static_chain_decl) |
| { |
| if (dump_file) |
| fprintf (dump_file, "Not splitting: nested function.\n"); |
| return 0; |
| } |
| |
| /* See if it makes sense to try to split. |
| It makes sense to split if we inline, that is if we have direct calls to |
| handle or direct calls are possibly going to appear as result of indirect |
| inlining or LTO. Also handle -fprofile-generate as LTO to allow non-LTO |
| training for LTO -fprofile-use build. |
| |
| Note that we are not completely conservative about disqualifying functions |
| called once. It is possible that the caller is called more then once and |
| then inlining would still benefit. */ |
| if ((!node->callers |
| /* Local functions called once will be completely inlined most of time. */ |
| || (!node->callers->next_caller && node->local.local)) |
| && !node->address_taken |
| && !node->has_aliases_p () |
| && (!flag_lto || !node->externally_visible)) |
| { |
| if (dump_file) |
| fprintf (dump_file, "Not splitting: not called directly " |
| "or called once.\n"); |
| return 0; |
| } |
| |
| /* FIXME: We can actually split if splitting reduces call overhead. */ |
| if (!flag_inline_small_functions |
| && !DECL_DECLARED_INLINE_P (current_function_decl)) |
| { |
| if (dump_file) |
| fprintf (dump_file, "Not splitting: not autoinlining and function" |
| " is not inline.\n"); |
| return 0; |
| } |
| |
| /* We enforce splitting after loop headers when profile info is not |
| available. */ |
| if (profile_status_for_fn (cfun) != PROFILE_READ) |
| mark_dfs_back_edges (); |
| |
| /* Initialize bitmap to track forbidden calls. */ |
| forbidden_dominators = BITMAP_ALLOC (NULL); |
| calculate_dominance_info (CDI_DOMINATORS); |
| |
| /* Compute local info about basic blocks and determine function size/time. */ |
| bb_info_vec.safe_grow_cleared (last_basic_block_for_fn (cfun) + 1); |
| memset (&best_split_point, 0, sizeof (best_split_point)); |
| basic_block return_bb = find_return_bb (); |
| int tsan_exit_found = -1; |
| FOR_EACH_BB_FN (bb, cfun) |
| { |
| int time = 0; |
| int size = 0; |
| int freq = compute_call_stmt_bb_frequency (current_function_decl, bb); |
| |
| if (dump_file && (dump_flags & TDF_DETAILS)) |
| fprintf (dump_file, "Basic block %i\n", bb->index); |
| |
| for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi); gsi_next (&bsi)) |
| { |
| int this_time, this_size; |
| gimple *stmt = gsi_stmt (bsi); |
| |
| this_size = estimate_num_insns (stmt, &eni_size_weights); |
| this_time = estimate_num_insns (stmt, &eni_time_weights) * freq; |
| size += this_size; |
| time += this_time; |
| check_forbidden_calls (stmt); |
| |
| if (dump_file && (dump_flags & TDF_DETAILS)) |
| { |
| fprintf (dump_file, " freq:%6i size:%3i time:%3i ", |
| freq, this_size, this_time); |
| print_gimple_stmt (dump_file, stmt, 0, 0); |
| } |
| |
| if ((flag_sanitize & SANITIZE_THREAD) |
| && gimple_call_internal_p (stmt, IFN_TSAN_FUNC_EXIT)) |
| { |
| /* We handle TSAN_FUNC_EXIT for splitting either in the |
| return_bb, or in its immediate predecessors. */ |
| if ((bb != return_bb && !find_edge (bb, return_bb)) |
| || (tsan_exit_found != -1 |
| && tsan_exit_found != (bb != return_bb))) |
| { |
| if (dump_file) |
| fprintf (dump_file, "Not splitting: TSAN_FUNC_EXIT" |
| " in unexpected basic block.\n"); |
| BITMAP_FREE (forbidden_dominators); |
| bb_info_vec.release (); |
| return 0; |
| } |
| tsan_exit_found = bb != return_bb; |
| } |
| } |
| overall_time += time; |
| overall_size += size; |
| bb_info_vec[bb->index].time = time; |
| bb_info_vec[bb->index].size = size; |
| } |
| find_split_points (return_bb, overall_time, overall_size); |
| if (best_split_point.split_bbs) |
| { |
| split_function (return_bb, &best_split_point, tsan_exit_found == 1); |
| BITMAP_FREE (best_split_point.ssa_names_to_pass); |
| BITMAP_FREE (best_split_point.split_bbs); |
| todo = TODO_update_ssa | TODO_cleanup_cfg; |
| } |
| BITMAP_FREE (forbidden_dominators); |
| bb_info_vec.release (); |
| return todo; |
| } |
| |
| namespace { |
| |
| const pass_data pass_data_split_functions = |
| { |
| GIMPLE_PASS, /* type */ |
| "fnsplit", /* name */ |
| OPTGROUP_NONE, /* optinfo_flags */ |
| TV_IPA_FNSPLIT, /* tv_id */ |
| PROP_cfg, /* properties_required */ |
| 0, /* properties_provided */ |
| 0, /* properties_destroyed */ |
| 0, /* todo_flags_start */ |
| 0, /* todo_flags_finish */ |
| }; |
| |
| class pass_split_functions : public gimple_opt_pass |
| { |
| public: |
| pass_split_functions (gcc::context *ctxt) |
| : gimple_opt_pass (pass_data_split_functions, ctxt) |
| {} |
| |
| /* opt_pass methods: */ |
| virtual bool gate (function *); |
| virtual unsigned int execute (function *) |
| { |
| return execute_split_functions (); |
| } |
| |
| }; // class pass_split_functions |
| |
| bool |
| pass_split_functions::gate (function *) |
| { |
| /* When doing profile feedback, we want to execute the pass after profiling |
| is read. So disable one in early optimization. */ |
| return (flag_partial_inlining |
| && !profile_arc_flag && !flag_branch_probabilities); |
| } |
| |
| } // anon namespace |
| |
| gimple_opt_pass * |
| make_pass_split_functions (gcc::context *ctxt) |
| { |
| return new pass_split_functions (ctxt); |
| } |
| |
| /* Execute function splitting pass. */ |
| |
| static unsigned int |
| execute_feedback_split_functions (void) |
| { |
| unsigned int retval = execute_split_functions (); |
| if (retval) |
| retval |= TODO_rebuild_cgraph_edges; |
| return retval; |
| } |
| |
| namespace { |
| |
| const pass_data pass_data_feedback_split_functions = |
| { |
| GIMPLE_PASS, /* type */ |
| "feedback_fnsplit", /* name */ |
| OPTGROUP_NONE, /* optinfo_flags */ |
| TV_IPA_FNSPLIT, /* tv_id */ |
| PROP_cfg, /* properties_required */ |
| 0, /* properties_provided */ |
| 0, /* properties_destroyed */ |
| 0, /* todo_flags_start */ |
| 0, /* todo_flags_finish */ |
| }; |
| |
| class pass_feedback_split_functions : public gimple_opt_pass |
| { |
| public: |
| pass_feedback_split_functions (gcc::context *ctxt) |
| : gimple_opt_pass (pass_data_feedback_split_functions, ctxt) |
| {} |
| |
| /* opt_pass methods: */ |
| virtual bool gate (function *); |
| virtual unsigned int execute (function *) |
| { |
| return execute_feedback_split_functions (); |
| } |
| |
| }; // class pass_feedback_split_functions |
| |
| bool |
| pass_feedback_split_functions::gate (function *) |
| { |
| /* We don't need to split when profiling at all, we are producing |
| lousy code anyway. */ |
| return (flag_partial_inlining |
| && flag_branch_probabilities); |
| } |
| |
| } // anon namespace |
| |
| gimple_opt_pass * |
| make_pass_feedback_split_functions (gcc::context *ctxt) |
| { |
| return new pass_feedback_split_functions (ctxt); |
| } |