| /* Iterator routines for GIMPLE statements. |
| Copyright (C) 2007-2019 Free Software Foundation, Inc. |
| Contributed by Aldy Hernandez <aldy@quesejoda.com> |
| |
| 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/>. */ |
| |
| #include "config.h" |
| #include "system.h" |
| #include "coretypes.h" |
| #include "backend.h" |
| #include "tree.h" |
| #include "gimple.h" |
| #include "cfghooks.h" |
| #include "ssa.h" |
| #include "cgraph.h" |
| #include "tree-eh.h" |
| #include "gimple-iterator.h" |
| #include "tree-cfg.h" |
| #include "tree-ssa.h" |
| #include "value-prof.h" |
| |
| |
| /* Mark the statement STMT as modified, and update it. */ |
| |
| static inline void |
| update_modified_stmt (gimple *stmt) |
| { |
| if (!ssa_operands_active (cfun)) |
| return; |
| update_stmt_if_modified (stmt); |
| } |
| |
| |
| /* Mark the statements in SEQ as modified, and update them. */ |
| |
| void |
| update_modified_stmts (gimple_seq seq) |
| { |
| gimple_stmt_iterator gsi; |
| |
| if (!ssa_operands_active (cfun)) |
| return; |
| for (gsi = gsi_start (seq); !gsi_end_p (gsi); gsi_next (&gsi)) |
| update_stmt_if_modified (gsi_stmt (gsi)); |
| } |
| |
| |
| /* Set BB to be the basic block for all the statements in the list |
| starting at FIRST and LAST. */ |
| |
| static void |
| update_bb_for_stmts (gimple_seq_node first, gimple_seq_node last, |
| basic_block bb) |
| { |
| gimple_seq_node n; |
| |
| for (n = first; n; n = n->next) |
| { |
| gimple_set_bb (n, bb); |
| if (n == last) |
| break; |
| } |
| } |
| |
| /* Set the frequencies for the cgraph_edges for each of the calls |
| starting at FIRST for their new position within BB. */ |
| |
| static void |
| update_call_edge_frequencies (gimple_seq_node first, basic_block bb) |
| { |
| struct cgraph_node *cfun_node = NULL; |
| gimple_seq_node n; |
| |
| for (n = first; n ; n = n->next) |
| if (is_gimple_call (n)) |
| { |
| struct cgraph_edge *e; |
| |
| /* These function calls are expensive enough that we want |
| to avoid calling them if we never see any calls. */ |
| if (cfun_node == NULL) |
| cfun_node = cgraph_node::get (current_function_decl); |
| |
| e = cfun_node->get_edge (n); |
| if (e != NULL) |
| e->count = bb->count; |
| } |
| } |
| |
| /* Insert the sequence delimited by nodes FIRST and LAST before |
| iterator I. M specifies how to update iterator I after insertion |
| (see enum gsi_iterator_update). |
| |
| This routine assumes that there is a forward and backward path |
| between FIRST and LAST (i.e., they are linked in a doubly-linked |
| list). Additionally, if FIRST == LAST, this routine will properly |
| insert a single node. */ |
| |
| static void |
| gsi_insert_seq_nodes_before (gimple_stmt_iterator *i, |
| gimple_seq_node first, |
| gimple_seq_node last, |
| enum gsi_iterator_update mode) |
| { |
| basic_block bb; |
| gimple_seq_node cur = i->ptr; |
| |
| gcc_assert (!cur || cur->prev); |
| |
| if ((bb = gsi_bb (*i)) != NULL) |
| update_bb_for_stmts (first, last, bb); |
| |
| /* Link SEQ before CUR in the sequence. */ |
| if (cur) |
| { |
| first->prev = cur->prev; |
| if (first->prev->next) |
| first->prev->next = first; |
| else |
| gimple_seq_set_first (i->seq, first); |
| last->next = cur; |
| cur->prev = last; |
| } |
| else |
| { |
| gimple_seq_node itlast = gimple_seq_last (*i->seq); |
| |
| /* If CUR is NULL, we link at the end of the sequence (this case happens |
| when gsi_after_labels is called for a basic block that contains only |
| labels, so it returns an iterator after the end of the block, and |
| we need to insert before it; it might be cleaner to add a flag to the |
| iterator saying whether we are at the start or end of the list). */ |
| last->next = NULL; |
| if (itlast) |
| { |
| first->prev = itlast; |
| itlast->next = first; |
| } |
| else |
| gimple_seq_set_first (i->seq, first); |
| gimple_seq_set_last (i->seq, last); |
| } |
| |
| /* Update the iterator, if requested. */ |
| switch (mode) |
| { |
| case GSI_NEW_STMT: |
| case GSI_CONTINUE_LINKING: |
| i->ptr = first; |
| break; |
| case GSI_SAME_STMT: |
| break; |
| default: |
| gcc_unreachable (); |
| } |
| } |
| |
| |
| /* Inserts the sequence of statements SEQ before the statement pointed |
| by iterator I. MODE indicates what to do with the iterator after |
| insertion (see enum gsi_iterator_update). |
| |
| This function does not scan for new operands. It is provided for |
| the use of the gimplifier, which manipulates statements for which |
| def/use information has not yet been constructed. Most callers |
| should use gsi_insert_seq_before. */ |
| |
| void |
| gsi_insert_seq_before_without_update (gimple_stmt_iterator *i, gimple_seq seq, |
| enum gsi_iterator_update mode) |
| { |
| gimple_seq_node first, last; |
| |
| if (seq == NULL) |
| return; |
| |
| /* Don't allow inserting a sequence into itself. */ |
| gcc_assert (seq != *i->seq); |
| |
| first = gimple_seq_first (seq); |
| last = gimple_seq_last (seq); |
| |
| /* Empty sequences need no work. */ |
| if (!first || !last) |
| { |
| gcc_assert (first == last); |
| return; |
| } |
| |
| gsi_insert_seq_nodes_before (i, first, last, mode); |
| } |
| |
| |
| /* Inserts the sequence of statements SEQ before the statement pointed |
| by iterator I. MODE indicates what to do with the iterator after |
| insertion (see enum gsi_iterator_update). Scan the statements in SEQ |
| for new operands. */ |
| |
| void |
| gsi_insert_seq_before (gimple_stmt_iterator *i, gimple_seq seq, |
| enum gsi_iterator_update mode) |
| { |
| update_modified_stmts (seq); |
| gsi_insert_seq_before_without_update (i, seq, mode); |
| } |
| |
| |
| /* Insert the sequence delimited by nodes FIRST and LAST after |
| iterator I. M specifies how to update iterator I after insertion |
| (see enum gsi_iterator_update). |
| |
| This routine assumes that there is a forward and backward path |
| between FIRST and LAST (i.e., they are linked in a doubly-linked |
| list). Additionally, if FIRST == LAST, this routine will properly |
| insert a single node. */ |
| |
| static void |
| gsi_insert_seq_nodes_after (gimple_stmt_iterator *i, |
| gimple_seq_node first, |
| gimple_seq_node last, |
| enum gsi_iterator_update m) |
| { |
| basic_block bb; |
| gimple_seq_node cur = i->ptr; |
| |
| gcc_assert (!cur || cur->prev); |
| |
| /* If the iterator is inside a basic block, we need to update the |
| basic block information for all the nodes between FIRST and LAST. */ |
| if ((bb = gsi_bb (*i)) != NULL) |
| update_bb_for_stmts (first, last, bb); |
| |
| /* Link SEQ after CUR. */ |
| if (cur) |
| { |
| last->next = cur->next; |
| if (last->next) |
| { |
| last->next->prev = last; |
| } |
| else |
| gimple_seq_set_last (i->seq, last); |
| first->prev = cur; |
| cur->next = first; |
| } |
| else |
| { |
| gcc_assert (!gimple_seq_last (*i->seq)); |
| last->next = NULL; |
| gimple_seq_set_first (i->seq, first); |
| gimple_seq_set_last (i->seq, last); |
| } |
| |
| /* Update the iterator, if requested. */ |
| switch (m) |
| { |
| case GSI_NEW_STMT: |
| i->ptr = first; |
| break; |
| case GSI_CONTINUE_LINKING: |
| i->ptr = last; |
| break; |
| case GSI_SAME_STMT: |
| gcc_assert (cur); |
| break; |
| default: |
| gcc_unreachable (); |
| } |
| } |
| |
| |
| /* Links sequence SEQ after the statement pointed-to by iterator I. |
| MODE is as in gsi_insert_after. |
| |
| This function does not scan for new operands. It is provided for |
| the use of the gimplifier, which manipulates statements for which |
| def/use information has not yet been constructed. Most callers |
| should use gsi_insert_seq_after. */ |
| |
| void |
| gsi_insert_seq_after_without_update (gimple_stmt_iterator *i, gimple_seq seq, |
| enum gsi_iterator_update mode) |
| { |
| gimple_seq_node first, last; |
| |
| if (seq == NULL) |
| return; |
| |
| /* Don't allow inserting a sequence into itself. */ |
| gcc_assert (seq != *i->seq); |
| |
| first = gimple_seq_first (seq); |
| last = gimple_seq_last (seq); |
| |
| /* Empty sequences need no work. */ |
| if (!first || !last) |
| { |
| gcc_assert (first == last); |
| return; |
| } |
| |
| gsi_insert_seq_nodes_after (i, first, last, mode); |
| } |
| |
| |
| /* Links sequence SEQ after the statement pointed-to by iterator I. |
| MODE is as in gsi_insert_after. Scan the statements in SEQ |
| for new operands. */ |
| |
| void |
| gsi_insert_seq_after (gimple_stmt_iterator *i, gimple_seq seq, |
| enum gsi_iterator_update mode) |
| { |
| update_modified_stmts (seq); |
| gsi_insert_seq_after_without_update (i, seq, mode); |
| } |
| |
| |
| /* Move all statements in the sequence after I to a new sequence. |
| Return this new sequence. */ |
| |
| gimple_seq |
| gsi_split_seq_after (gimple_stmt_iterator i) |
| { |
| gimple_seq_node cur, next; |
| gimple_seq *pold_seq, new_seq; |
| |
| cur = i.ptr; |
| |
| /* How can we possibly split after the end, or before the beginning? */ |
| gcc_assert (cur && cur->next); |
| next = cur->next; |
| |
| pold_seq = i.seq; |
| |
| gimple_seq_set_first (&new_seq, next); |
| gimple_seq_set_last (&new_seq, gimple_seq_last (*pold_seq)); |
| gimple_seq_set_last (pold_seq, cur); |
| cur->next = NULL; |
| |
| return new_seq; |
| } |
| |
| |
| /* Set the statement to which GSI points to STMT. This only updates |
| the iterator and the gimple sequence, it doesn't do the bookkeeping |
| of gsi_replace. */ |
| |
| void |
| gsi_set_stmt (gimple_stmt_iterator *gsi, gimple *stmt) |
| { |
| gimple *orig_stmt = gsi_stmt (*gsi); |
| gimple *prev, *next; |
| |
| stmt->next = next = orig_stmt->next; |
| stmt->prev = prev = orig_stmt->prev; |
| /* Note how we don't clear next/prev of orig_stmt. This is so that |
| copies of *GSI our callers might still hold (to orig_stmt) |
| can be advanced as if they too were replaced. */ |
| if (prev->next) |
| prev->next = stmt; |
| else |
| gimple_seq_set_first (gsi->seq, stmt); |
| if (next) |
| next->prev = stmt; |
| else |
| gimple_seq_set_last (gsi->seq, stmt); |
| |
| gsi->ptr = stmt; |
| } |
| |
| |
| /* Move all statements in the sequence before I to a new sequence. |
| Return this new sequence. I is set to the head of the new list. */ |
| |
| void |
| gsi_split_seq_before (gimple_stmt_iterator *i, gimple_seq *pnew_seq) |
| { |
| gimple_seq_node cur, prev; |
| gimple_seq old_seq; |
| |
| cur = i->ptr; |
| |
| /* How can we possibly split after the end? */ |
| gcc_assert (cur); |
| prev = cur->prev; |
| |
| old_seq = *i->seq; |
| if (!prev->next) |
| *i->seq = NULL; |
| i->seq = pnew_seq; |
| |
| /* Set the limits on NEW_SEQ. */ |
| gimple_seq_set_first (pnew_seq, cur); |
| gimple_seq_set_last (pnew_seq, gimple_seq_last (old_seq)); |
| |
| /* Cut OLD_SEQ before I. */ |
| gimple_seq_set_last (&old_seq, prev); |
| if (prev->next) |
| prev->next = NULL; |
| } |
| |
| |
| /* Replace the statement pointed-to by GSI to STMT. If UPDATE_EH_INFO |
| is true, the exception handling information of the original |
| statement is moved to the new statement. Assignments must only be |
| replaced with assignments to the same LHS. Returns whether EH edge |
| cleanup is required. */ |
| |
| bool |
| gsi_replace (gimple_stmt_iterator *gsi, gimple *stmt, bool update_eh_info) |
| { |
| gimple *orig_stmt = gsi_stmt (*gsi); |
| bool require_eh_edge_purge = false; |
| |
| if (stmt == orig_stmt) |
| return false; |
| |
| gcc_assert (!gimple_has_lhs (orig_stmt) || !gimple_has_lhs (stmt) |
| || gimple_get_lhs (orig_stmt) == gimple_get_lhs (stmt)); |
| |
| gimple_set_location (stmt, gimple_location (orig_stmt)); |
| gimple_set_bb (stmt, gsi_bb (*gsi)); |
| |
| /* Preserve EH region information from the original statement, if |
| requested by the caller. */ |
| if (update_eh_info) |
| require_eh_edge_purge = maybe_clean_or_replace_eh_stmt (orig_stmt, stmt); |
| |
| gimple_duplicate_stmt_histograms (cfun, stmt, cfun, orig_stmt); |
| |
| /* Free all the data flow information for ORIG_STMT. */ |
| gimple_set_bb (orig_stmt, NULL); |
| gimple_remove_stmt_histograms (cfun, orig_stmt); |
| delink_stmt_imm_use (orig_stmt); |
| |
| gsi_set_stmt (gsi, stmt); |
| gimple_set_modified (stmt, true); |
| update_modified_stmt (stmt); |
| return require_eh_edge_purge; |
| } |
| |
| |
| /* Replace the statement pointed-to by GSI with the sequence SEQ. |
| If UPDATE_EH_INFO is true, the exception handling information of |
| the original statement is moved to the last statement of the new |
| sequence. If the old statement is an assignment, then so must |
| be the last statement of the new sequence, and they must have the |
| same LHS. */ |
| |
| void |
| gsi_replace_with_seq (gimple_stmt_iterator *gsi, gimple_seq seq, |
| bool update_eh_info) |
| { |
| gimple_stmt_iterator seqi; |
| gimple *last; |
| if (gimple_seq_empty_p (seq)) |
| { |
| gsi_remove (gsi, true); |
| return; |
| } |
| seqi = gsi_last (seq); |
| last = gsi_stmt (seqi); |
| gsi_remove (&seqi, false); |
| gsi_insert_seq_before (gsi, seq, GSI_SAME_STMT); |
| gsi_replace (gsi, last, update_eh_info); |
| } |
| |
| |
| /* Insert statement STMT before the statement pointed-to by iterator I. |
| M specifies how to update iterator I after insertion (see enum |
| gsi_iterator_update). |
| |
| This function does not scan for new operands. It is provided for |
| the use of the gimplifier, which manipulates statements for which |
| def/use information has not yet been constructed. Most callers |
| should use gsi_insert_before. */ |
| |
| void |
| gsi_insert_before_without_update (gimple_stmt_iterator *i, gimple *stmt, |
| enum gsi_iterator_update m) |
| { |
| gsi_insert_seq_nodes_before (i, stmt, stmt, m); |
| } |
| |
| /* Insert statement STMT before the statement pointed-to by iterator I. |
| Update STMT's basic block and scan it for new operands. M |
| specifies how to update iterator I after insertion (see enum |
| gsi_iterator_update). */ |
| |
| void |
| gsi_insert_before (gimple_stmt_iterator *i, gimple *stmt, |
| enum gsi_iterator_update m) |
| { |
| update_modified_stmt (stmt); |
| gsi_insert_before_without_update (i, stmt, m); |
| } |
| |
| |
| /* Insert statement STMT after the statement pointed-to by iterator I. |
| M specifies how to update iterator I after insertion (see enum |
| gsi_iterator_update). |
| |
| This function does not scan for new operands. It is provided for |
| the use of the gimplifier, which manipulates statements for which |
| def/use information has not yet been constructed. Most callers |
| should use gsi_insert_after. */ |
| |
| void |
| gsi_insert_after_without_update (gimple_stmt_iterator *i, gimple *stmt, |
| enum gsi_iterator_update m) |
| { |
| gsi_insert_seq_nodes_after (i, stmt, stmt, m); |
| } |
| |
| |
| /* Insert statement STMT after the statement pointed-to by iterator I. |
| Update STMT's basic block and scan it for new operands. M |
| specifies how to update iterator I after insertion (see enum |
| gsi_iterator_update). */ |
| |
| void |
| gsi_insert_after (gimple_stmt_iterator *i, gimple *stmt, |
| enum gsi_iterator_update m) |
| { |
| update_modified_stmt (stmt); |
| gsi_insert_after_without_update (i, stmt, m); |
| } |
| |
| |
| /* Remove the current stmt from the sequence. The iterator is updated |
| to point to the next statement. |
| |
| REMOVE_PERMANENTLY is true when the statement is going to be removed |
| from the IL and not reinserted elsewhere. In that case we remove the |
| statement pointed to by iterator I from the EH tables, and free its |
| operand caches. Otherwise we do not modify this information. Returns |
| true whether EH edge cleanup is required. */ |
| |
| bool |
| gsi_remove (gimple_stmt_iterator *i, bool remove_permanently) |
| { |
| gimple_seq_node cur, next, prev; |
| gimple *stmt = gsi_stmt (*i); |
| bool require_eh_edge_purge = false; |
| |
| if (gimple_code (stmt) != GIMPLE_PHI) |
| insert_debug_temps_for_defs (i); |
| |
| /* Free all the data flow information for STMT. */ |
| gimple_set_bb (stmt, NULL); |
| delink_stmt_imm_use (stmt); |
| gimple_set_modified (stmt, true); |
| |
| if (remove_permanently) |
| { |
| if (gimple_debug_nonbind_marker_p (stmt)) |
| /* We don't need this to be exact, but try to keep it at least |
| close. */ |
| cfun->debug_marker_count--; |
| require_eh_edge_purge = remove_stmt_from_eh_lp (stmt); |
| gimple_remove_stmt_histograms (cfun, stmt); |
| } |
| |
| /* Update the iterator and re-wire the links in I->SEQ. */ |
| cur = i->ptr; |
| next = cur->next; |
| prev = cur->prev; |
| /* See gsi_set_stmt for why we don't reset prev/next of STMT. */ |
| |
| if (next) |
| /* Cur is not last. */ |
| next->prev = prev; |
| else if (prev->next) |
| /* Cur is last but not first. */ |
| gimple_seq_set_last (i->seq, prev); |
| |
| if (prev->next) |
| /* Cur is not first. */ |
| prev->next = next; |
| else |
| /* Cur is first. */ |
| *i->seq = next; |
| |
| i->ptr = next; |
| |
| return require_eh_edge_purge; |
| } |
| |
| |
| /* Finds iterator for STMT. */ |
| |
| gimple_stmt_iterator |
| gsi_for_stmt (gimple *stmt) |
| { |
| gimple_stmt_iterator i; |
| basic_block bb = gimple_bb (stmt); |
| |
| if (gimple_code (stmt) == GIMPLE_PHI) |
| i = gsi_start_phis (bb); |
| else |
| i = gsi_start_bb (bb); |
| |
| i.ptr = stmt; |
| return i; |
| } |
| |
| /* Get an iterator for STMT, which is known to belong to SEQ. This is |
| equivalent to starting at the beginning of SEQ and searching forward |
| until STMT is found. */ |
| |
| gimple_stmt_iterator |
| gsi_for_stmt (gimple *stmt, gimple_seq *seq) |
| { |
| gimple_stmt_iterator i = gsi_start_1 (seq); |
| i.ptr = stmt; |
| return i; |
| } |
| |
| /* Finds iterator for PHI. */ |
| |
| gphi_iterator |
| gsi_for_phi (gphi *phi) |
| { |
| gphi_iterator i; |
| basic_block bb = gimple_bb (phi); |
| |
| i = gsi_start_phis (bb); |
| i.ptr = phi; |
| |
| return i; |
| } |
| |
| /* Move the statement at FROM so it comes right after the statement at TO. */ |
| |
| void |
| gsi_move_after (gimple_stmt_iterator *from, gimple_stmt_iterator *to) |
| { |
| gimple *stmt = gsi_stmt (*from); |
| gsi_remove (from, false); |
| |
| /* We must have GSI_NEW_STMT here, as gsi_move_after is sometimes used to |
| move statements to an empty block. */ |
| gsi_insert_after (to, stmt, GSI_NEW_STMT); |
| } |
| |
| |
| /* Move the statement at FROM so it comes right before the statement |
| at TO. */ |
| |
| void |
| gsi_move_before (gimple_stmt_iterator *from, gimple_stmt_iterator *to) |
| { |
| gimple *stmt = gsi_stmt (*from); |
| gsi_remove (from, false); |
| |
| /* For consistency with gsi_move_after, it might be better to have |
| GSI_NEW_STMT here; however, that breaks several places that expect |
| that TO does not change. */ |
| gsi_insert_before (to, stmt, GSI_SAME_STMT); |
| } |
| |
| |
| /* Move the statement at FROM to the end of basic block BB. */ |
| |
| void |
| gsi_move_to_bb_end (gimple_stmt_iterator *from, basic_block bb) |
| { |
| gimple_stmt_iterator last = gsi_last_bb (bb); |
| gcc_checking_assert (gsi_bb (last) == bb); |
| |
| /* Have to check gsi_end_p because it could be an empty block. */ |
| if (!gsi_end_p (last) && is_ctrl_stmt (gsi_stmt (last))) |
| gsi_move_before (from, &last); |
| else |
| gsi_move_after (from, &last); |
| } |
| |
| |
| /* Add STMT to the pending list of edge E. No actual insertion is |
| made until a call to gsi_commit_edge_inserts () is made. */ |
| |
| void |
| gsi_insert_on_edge (edge e, gimple *stmt) |
| { |
| gimple_seq_add_stmt (&PENDING_STMT (e), stmt); |
| } |
| |
| /* Add the sequence of statements SEQ to the pending list of edge E. |
| No actual insertion is made until a call to gsi_commit_edge_inserts |
| is made. */ |
| |
| void |
| gsi_insert_seq_on_edge (edge e, gimple_seq seq) |
| { |
| gimple_seq_add_seq (&PENDING_STMT (e), seq); |
| } |
| |
| /* Return a new iterator pointing to the first statement in sequence of |
| statements on edge E. Such statements need to be subsequently moved into a |
| basic block by calling gsi_commit_edge_inserts. */ |
| |
| gimple_stmt_iterator |
| gsi_start_edge (edge e) |
| { |
| return gsi_start (PENDING_STMT (e)); |
| } |
| |
| /* Insert the statement pointed-to by GSI into edge E. Every attempt |
| is made to place the statement in an existing basic block, but |
| sometimes that isn't possible. When it isn't possible, the edge is |
| split and the statement is added to the new block. |
| |
| In all cases, the returned *GSI points to the correct location. The |
| return value is true if insertion should be done after the location, |
| or false if it should be done before the location. If a new basic block |
| has to be created, it is stored in *NEW_BB. */ |
| |
| static bool |
| gimple_find_edge_insert_loc (edge e, gimple_stmt_iterator *gsi, |
| basic_block *new_bb) |
| { |
| basic_block dest, src; |
| gimple *tmp; |
| |
| dest = e->dest; |
| |
| /* If the destination has one predecessor which has no PHI nodes, |
| insert there. Except for the exit block. |
| |
| The requirement for no PHI nodes could be relaxed. Basically we |
| would have to examine the PHIs to prove that none of them used |
| the value set by the statement we want to insert on E. That |
| hardly seems worth the effort. */ |
| restart: |
| if (single_pred_p (dest) |
| && gimple_seq_empty_p (phi_nodes (dest)) |
| && dest != EXIT_BLOCK_PTR_FOR_FN (cfun)) |
| { |
| *gsi = gsi_start_bb (dest); |
| if (gsi_end_p (*gsi)) |
| return true; |
| |
| /* Make sure we insert after any leading labels. */ |
| tmp = gsi_stmt (*gsi); |
| while (gimple_code (tmp) == GIMPLE_LABEL) |
| { |
| gsi_next (gsi); |
| if (gsi_end_p (*gsi)) |
| break; |
| tmp = gsi_stmt (*gsi); |
| } |
| |
| if (gsi_end_p (*gsi)) |
| { |
| *gsi = gsi_last_bb (dest); |
| return true; |
| } |
| else |
| return false; |
| } |
| |
| /* If the source has one successor, the edge is not abnormal and |
| the last statement does not end a basic block, insert there. |
| Except for the entry block. */ |
| src = e->src; |
| if ((e->flags & EDGE_ABNORMAL) == 0 |
| && (single_succ_p (src) |
| /* Do not count a fake edge as successor as added to infinite |
| loops by connect_infinite_loops_to_exit. */ |
| || (EDGE_COUNT (src->succs) == 2 |
| && (EDGE_SUCC (src, 0)->flags & EDGE_FAKE |
| || EDGE_SUCC (src, 1)->flags & EDGE_FAKE))) |
| && src != ENTRY_BLOCK_PTR_FOR_FN (cfun)) |
| { |
| *gsi = gsi_last_bb (src); |
| if (gsi_end_p (*gsi)) |
| return true; |
| |
| tmp = gsi_stmt (*gsi); |
| if (is_gimple_debug (tmp)) |
| { |
| gimple_stmt_iterator si = *gsi; |
| gsi_prev_nondebug (&si); |
| if (!gsi_end_p (si)) |
| tmp = gsi_stmt (si); |
| /* If we don't have a BB-ending nondebug stmt, we want to |
| insert after the trailing debug stmts. Otherwise, we may |
| insert before the BB-ending nondebug stmt, or split the |
| edge. */ |
| if (!stmt_ends_bb_p (tmp)) |
| return true; |
| *gsi = si; |
| } |
| else if (!stmt_ends_bb_p (tmp)) |
| return true; |
| |
| switch (gimple_code (tmp)) |
| { |
| case GIMPLE_RETURN: |
| case GIMPLE_RESX: |
| return false; |
| default: |
| break; |
| } |
| } |
| |
| /* Otherwise, create a new basic block, and split this edge. */ |
| dest = split_edge (e); |
| if (new_bb) |
| *new_bb = dest; |
| e = single_pred_edge (dest); |
| goto restart; |
| } |
| |
| |
| /* Similar to gsi_insert_on_edge+gsi_commit_edge_inserts. If a new |
| block has to be created, it is returned. */ |
| |
| basic_block |
| gsi_insert_on_edge_immediate (edge e, gimple *stmt) |
| { |
| gimple_stmt_iterator gsi; |
| basic_block new_bb = NULL; |
| bool ins_after; |
| |
| gcc_assert (!PENDING_STMT (e)); |
| |
| ins_after = gimple_find_edge_insert_loc (e, &gsi, &new_bb); |
| |
| update_call_edge_frequencies (stmt, gsi.bb); |
| |
| if (ins_after) |
| gsi_insert_after (&gsi, stmt, GSI_NEW_STMT); |
| else |
| gsi_insert_before (&gsi, stmt, GSI_NEW_STMT); |
| |
| return new_bb; |
| } |
| |
| /* Insert STMTS on edge E. If a new block has to be created, it |
| is returned. */ |
| |
| basic_block |
| gsi_insert_seq_on_edge_immediate (edge e, gimple_seq stmts) |
| { |
| gimple_stmt_iterator gsi; |
| basic_block new_bb = NULL; |
| bool ins_after; |
| |
| gcc_assert (!PENDING_STMT (e)); |
| |
| ins_after = gimple_find_edge_insert_loc (e, &gsi, &new_bb); |
| update_call_edge_frequencies (gimple_seq_first (stmts), gsi.bb); |
| |
| if (ins_after) |
| gsi_insert_seq_after (&gsi, stmts, GSI_NEW_STMT); |
| else |
| gsi_insert_seq_before (&gsi, stmts, GSI_NEW_STMT); |
| |
| return new_bb; |
| } |
| |
| /* This routine will commit all pending edge insertions, creating any new |
| basic blocks which are necessary. */ |
| |
| void |
| gsi_commit_edge_inserts (void) |
| { |
| basic_block bb; |
| edge e; |
| edge_iterator ei; |
| |
| gsi_commit_one_edge_insert (single_succ_edge (ENTRY_BLOCK_PTR_FOR_FN (cfun)), |
| NULL); |
| |
| FOR_EACH_BB_FN (bb, cfun) |
| FOR_EACH_EDGE (e, ei, bb->succs) |
| gsi_commit_one_edge_insert (e, NULL); |
| } |
| |
| |
| /* Commit insertions pending at edge E. If a new block is created, set NEW_BB |
| to this block, otherwise set it to NULL. */ |
| |
| void |
| gsi_commit_one_edge_insert (edge e, basic_block *new_bb) |
| { |
| if (new_bb) |
| *new_bb = NULL; |
| |
| if (PENDING_STMT (e)) |
| { |
| gimple_stmt_iterator gsi; |
| gimple_seq seq = PENDING_STMT (e); |
| bool ins_after; |
| |
| PENDING_STMT (e) = NULL; |
| |
| ins_after = gimple_find_edge_insert_loc (e, &gsi, new_bb); |
| update_call_edge_frequencies (gimple_seq_first (seq), gsi.bb); |
| |
| if (ins_after) |
| gsi_insert_seq_after (&gsi, seq, GSI_NEW_STMT); |
| else |
| gsi_insert_seq_before (&gsi, seq, GSI_NEW_STMT); |
| } |
| } |
| |
| /* Returns iterator at the start of the list of phi nodes of BB. */ |
| |
| gphi_iterator |
| gsi_start_phis (basic_block bb) |
| { |
| gimple_seq *pseq = phi_nodes_ptr (bb); |
| |
| /* Adapted from gsi_start_1. */ |
| gphi_iterator i; |
| |
| i.ptr = gimple_seq_first (*pseq); |
| i.seq = pseq; |
| i.bb = i.ptr ? gimple_bb (i.ptr) : NULL; |
| |
| return i; |
| } |