X-Git-Url: http://git.sourceforge.jp/view?a=blobdiff_plain;f=gcc%2Fcfghooks.c;h=0897b0df5653f07a050ee7a3bc04585ec3174a9f;hb=3b175f7919cd708b4df2cac98d831d2bd8132e1f;hp=525289c04f8413ac6901de73280594735a57b1e0;hpb=4c9e08a4756e16ab5af175be78dcdc0b61b73eab;p=pf3gnuchains%2Fgcc-fork.git diff --git a/gcc/cfghooks.c b/gcc/cfghooks.c index 525289c04f8..0897b0df565 100644 --- a/gcc/cfghooks.c +++ b/gcc/cfghooks.c @@ -1,12 +1,13 @@ /* Hooks for cfg representation specific functions. - Copyright (C) 2003 Free Software Foundation, Inc. + Copyright (C) 2003, 2004, 2005, 2007, 2008 Free Software Foundation, + Inc. Contributed by Sebastian Pop 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 2, or (at your option) +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, @@ -15,9 +16,8 @@ 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 COPYING. If not, write to -the Free Software Foundation, 59 Temple Place - Suite 330, -Boston, MA 02111-1307, USA. */ +along with GCC; see the file COPYING3. If not see +. */ #include "config.h" #include "system.h" @@ -26,12 +26,13 @@ Boston, MA 02111-1307, USA. */ #include "tree.h" #include "rtl.h" #include "basic-block.h" - -extern struct cfg_hooks rtl_cfg_hooks; -extern struct cfg_hooks cfg_layout_rtl_cfg_hooks; +#include "tree-flow.h" +#include "timevar.h" +#include "toplev.h" +#include "cfgloop.h" /* A pointer to one of the hooks containers. */ -struct cfg_hooks *cfg_hooks; +static struct cfg_hooks *cfg_hooks; /* Initialization of functions specific to the rtl IR. */ void @@ -46,3 +47,1040 @@ cfg_layout_rtl_register_cfg_hooks (void) { cfg_hooks = &cfg_layout_rtl_cfg_hooks; } + +/* Initialization of functions specific to the tree IR. */ + +void +gimple_register_cfg_hooks (void) +{ + cfg_hooks = &gimple_cfg_hooks; +} + +struct cfg_hooks +get_cfg_hooks (void) +{ + return *cfg_hooks; +} + +void +set_cfg_hooks (struct cfg_hooks new_cfg_hooks) +{ + *cfg_hooks = new_cfg_hooks; +} + +/* Returns current ir type. */ + +enum ir_type +current_ir_type (void) +{ + if (cfg_hooks == &gimple_cfg_hooks) + return IR_GIMPLE; + else if (cfg_hooks == &rtl_cfg_hooks) + return IR_RTL_CFGRTL; + else if (cfg_hooks == &cfg_layout_rtl_cfg_hooks) + return IR_RTL_CFGLAYOUT; + else + gcc_unreachable (); +} + +/* Verify the CFG consistency. + + Currently it does following: checks edge and basic block list correctness + and calls into IL dependent checking then. */ + +void +verify_flow_info (void) +{ + size_t *edge_checksum; + int err = 0; + basic_block bb, last_bb_seen; + basic_block *last_visited; + + timevar_push (TV_CFG_VERIFY); + last_visited = XCNEWVEC (basic_block, last_basic_block); + edge_checksum = XCNEWVEC (size_t, last_basic_block); + + /* Check bb chain & numbers. */ + last_bb_seen = ENTRY_BLOCK_PTR; + FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR->next_bb, NULL, next_bb) + { + if (bb != EXIT_BLOCK_PTR + && bb != BASIC_BLOCK (bb->index)) + { + error ("bb %d on wrong place", bb->index); + err = 1; + } + + if (bb->prev_bb != last_bb_seen) + { + error ("prev_bb of %d should be %d, not %d", + bb->index, last_bb_seen->index, bb->prev_bb->index); + err = 1; + } + + last_bb_seen = bb; + } + + /* Now check the basic blocks (boundaries etc.) */ + FOR_EACH_BB_REVERSE (bb) + { + int n_fallthru = 0; + edge e; + edge_iterator ei; + + if (bb->loop_father != NULL && current_loops == NULL) + { + error ("verify_flow_info: Block %i has loop_father, but there are no loops", + bb->index); + err = 1; + } + if (bb->loop_father == NULL && current_loops != NULL) + { + error ("verify_flow_info: Block %i lacks loop_father", bb->index); + err = 1; + } + + if (bb->count < 0) + { + error ("verify_flow_info: Wrong count of block %i %i", + bb->index, (int)bb->count); + err = 1; + } + if (bb->frequency < 0) + { + error ("verify_flow_info: Wrong frequency of block %i %i", + bb->index, bb->frequency); + err = 1; + } + FOR_EACH_EDGE (e, ei, bb->succs) + { + if (last_visited [e->dest->index] == bb) + { + error ("verify_flow_info: Duplicate edge %i->%i", + e->src->index, e->dest->index); + err = 1; + } + if (e->probability < 0 || e->probability > REG_BR_PROB_BASE) + { + error ("verify_flow_info: Wrong probability of edge %i->%i %i", + e->src->index, e->dest->index, e->probability); + err = 1; + } + if (e->count < 0) + { + error ("verify_flow_info: Wrong count of edge %i->%i %i", + e->src->index, e->dest->index, (int)e->count); + err = 1; + } + + last_visited [e->dest->index] = bb; + + if (e->flags & EDGE_FALLTHRU) + n_fallthru++; + + if (e->src != bb) + { + error ("verify_flow_info: Basic block %d succ edge is corrupted", + bb->index); + fprintf (stderr, "Predecessor: "); + dump_edge_info (stderr, e, 0); + fprintf (stderr, "\nSuccessor: "); + dump_edge_info (stderr, e, 1); + fprintf (stderr, "\n"); + err = 1; + } + + edge_checksum[e->dest->index] += (size_t) e; + } + if (n_fallthru > 1) + { + error ("wrong amount of branch edges after unconditional jump %i", bb->index); + err = 1; + } + + FOR_EACH_EDGE (e, ei, bb->preds) + { + if (e->dest != bb) + { + error ("basic block %d pred edge is corrupted", bb->index); + fputs ("Predecessor: ", stderr); + dump_edge_info (stderr, e, 0); + fputs ("\nSuccessor: ", stderr); + dump_edge_info (stderr, e, 1); + fputc ('\n', stderr); + err = 1; + } + + if (ei.index != e->dest_idx) + { + error ("basic block %d pred edge is corrupted", bb->index); + error ("its dest_idx should be %d, not %d", + ei.index, e->dest_idx); + fputs ("Predecessor: ", stderr); + dump_edge_info (stderr, e, 0); + fputs ("\nSuccessor: ", stderr); + dump_edge_info (stderr, e, 1); + fputc ('\n', stderr); + err = 1; + } + + edge_checksum[e->dest->index] -= (size_t) e; + } + } + + /* Complete edge checksumming for ENTRY and EXIT. */ + { + edge e; + edge_iterator ei; + + FOR_EACH_EDGE (e, ei, ENTRY_BLOCK_PTR->succs) + edge_checksum[e->dest->index] += (size_t) e; + + FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds) + edge_checksum[e->dest->index] -= (size_t) e; + } + + FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR, NULL, next_bb) + if (edge_checksum[bb->index]) + { + error ("basic block %i edge lists are corrupted", bb->index); + err = 1; + } + + last_bb_seen = ENTRY_BLOCK_PTR; + + /* Clean up. */ + free (last_visited); + free (edge_checksum); + + if (cfg_hooks->verify_flow_info) + err |= cfg_hooks->verify_flow_info (); + if (err) + internal_error ("verify_flow_info failed"); + timevar_pop (TV_CFG_VERIFY); +} + +/* Print out one basic block. This function takes care of the purely + graph related information. The cfg hook for the active representation + should dump representation-specific information. */ + +void +dump_bb (basic_block bb, FILE *outf, int indent) +{ + edge e; + edge_iterator ei; + char *s_indent; + + s_indent = (char *) alloca ((size_t) indent + 1); + memset (s_indent, ' ', (size_t) indent); + s_indent[indent] = '\0'; + + fprintf (outf, ";;%s basic block %d, loop depth %d, count ", + s_indent, bb->index, bb->loop_depth); + fprintf (outf, HOST_WIDEST_INT_PRINT_DEC, (HOST_WIDEST_INT) bb->count); + putc ('\n', outf); + + fprintf (outf, ";;%s prev block ", s_indent); + if (bb->prev_bb) + fprintf (outf, "%d, ", bb->prev_bb->index); + else + fprintf (outf, "(nil), "); + fprintf (outf, "next block "); + if (bb->next_bb) + fprintf (outf, "%d", bb->next_bb->index); + else + fprintf (outf, "(nil)"); + putc ('\n', outf); + + fprintf (outf, ";;%s pred: ", s_indent); + FOR_EACH_EDGE (e, ei, bb->preds) + dump_edge_info (outf, e, 0); + putc ('\n', outf); + + fprintf (outf, ";;%s succ: ", s_indent); + FOR_EACH_EDGE (e, ei, bb->succs) + dump_edge_info (outf, e, 1); + putc ('\n', outf); + + if (cfg_hooks->dump_bb) + cfg_hooks->dump_bb (bb, outf, indent, 0); +} + +/* Redirect edge E to the given basic block DEST and update underlying program + representation. Returns edge representing redirected branch (that may not + be equivalent to E in the case of duplicate edges being removed) or NULL + if edge is not easily redirectable for whatever reason. */ + +edge +redirect_edge_and_branch (edge e, basic_block dest) +{ + edge ret; + + if (!cfg_hooks->redirect_edge_and_branch) + internal_error ("%s does not support redirect_edge_and_branch", + cfg_hooks->name); + + ret = cfg_hooks->redirect_edge_and_branch (e, dest); + + /* If RET != E, then either the redirection failed, or the edge E + was removed since RET already lead to the same destination. */ + if (current_loops != NULL && ret == e) + rescan_loop_exit (e, false, false); + + return ret; +} + +/* Returns true if it is possible to remove the edge E by redirecting it + to the destination of the other edge going from its source. */ + +bool +can_remove_branch_p (const_edge e) +{ + if (!cfg_hooks->can_remove_branch_p) + internal_error ("%s does not support can_remove_branch_p", + cfg_hooks->name); + + if (EDGE_COUNT (e->src->succs) != 2) + return false; + + return cfg_hooks->can_remove_branch_p (e); +} + +/* Removes E, by redirecting it to the destination of the other edge going + from its source. Can_remove_branch_p must be true for E, hence this + operation cannot fail. */ + +void +remove_branch (edge e) +{ + edge other; + basic_block src = e->src; + int irr; + + gcc_assert (EDGE_COUNT (e->src->succs) == 2); + + other = EDGE_SUCC (src, EDGE_SUCC (src, 0) == e); + irr = other->flags & EDGE_IRREDUCIBLE_LOOP; + + e = redirect_edge_and_branch (e, other->dest); + gcc_assert (e != NULL); + + e->flags &= ~EDGE_IRREDUCIBLE_LOOP; + e->flags |= irr; +} + +/* Removes edge E from cfg. Unlike remove_branch, it does not update IL. */ + +void +remove_edge (edge e) +{ + if (current_loops != NULL) + rescan_loop_exit (e, false, true); + + remove_edge_raw (e); +} + +/* Redirect the edge E to basic block DEST even if it requires creating + of a new basic block; then it returns the newly created basic block. + Aborts when redirection is impossible. */ + +basic_block +redirect_edge_and_branch_force (edge e, basic_block dest) +{ + basic_block ret, src = e->src; + struct loop *loop; + + if (!cfg_hooks->redirect_edge_and_branch_force) + internal_error ("%s does not support redirect_edge_and_branch_force", + cfg_hooks->name); + + if (current_loops != NULL) + rescan_loop_exit (e, false, true); + + ret = cfg_hooks->redirect_edge_and_branch_force (e, dest); + if (ret != NULL + && dom_info_available_p (CDI_DOMINATORS)) + set_immediate_dominator (CDI_DOMINATORS, ret, src); + + if (current_loops != NULL) + { + if (ret != NULL) + { + loop = find_common_loop (single_pred (ret)->loop_father, + single_succ (ret)->loop_father); + add_bb_to_loop (ret, loop); + } + else if (find_edge (src, dest) == e) + rescan_loop_exit (e, true, false); + } + + return ret; +} + +/* Splits basic block BB after the specified instruction I (but at least after + the labels). If I is NULL, splits just after labels. The newly created edge + is returned. The new basic block is created just after the old one. */ + +edge +split_block (basic_block bb, void *i) +{ + basic_block new_bb; + + if (!cfg_hooks->split_block) + internal_error ("%s does not support split_block", cfg_hooks->name); + + new_bb = cfg_hooks->split_block (bb, i); + if (!new_bb) + return NULL; + + new_bb->count = bb->count; + new_bb->frequency = bb->frequency; + new_bb->loop_depth = bb->loop_depth; + + if (dom_info_available_p (CDI_DOMINATORS)) + { + redirect_immediate_dominators (CDI_DOMINATORS, bb, new_bb); + set_immediate_dominator (CDI_DOMINATORS, new_bb, bb); + } + + if (current_loops != NULL) + { + add_bb_to_loop (new_bb, bb->loop_father); + if (bb->loop_father->latch == bb) + bb->loop_father->latch = new_bb; + } + + return make_single_succ_edge (bb, new_bb, EDGE_FALLTHRU); +} + +/* Splits block BB just after labels. The newly created edge is returned. */ + +edge +split_block_after_labels (basic_block bb) +{ + return split_block (bb, NULL); +} + +/* Moves block BB immediately after block AFTER. Returns false if the + movement was impossible. */ + +bool +move_block_after (basic_block bb, basic_block after) +{ + bool ret; + + if (!cfg_hooks->move_block_after) + internal_error ("%s does not support move_block_after", cfg_hooks->name); + + ret = cfg_hooks->move_block_after (bb, after); + + return ret; +} + +/* Deletes the basic block BB. */ + +void +delete_basic_block (basic_block bb) +{ + if (!cfg_hooks->delete_basic_block) + internal_error ("%s does not support delete_basic_block", cfg_hooks->name); + + cfg_hooks->delete_basic_block (bb); + + if (current_loops != NULL) + { + struct loop *loop = bb->loop_father; + + /* If we remove the header or the latch of a loop, mark the loop for + removal by setting its header and latch to NULL. */ + if (loop->latch == bb + || loop->header == bb) + { + loop->header = NULL; + loop->latch = NULL; + } + + remove_bb_from_loops (bb); + } + + /* Remove the edges into and out of this block. Note that there may + indeed be edges in, if we are removing an unreachable loop. */ + while (EDGE_COUNT (bb->preds) != 0) + remove_edge (EDGE_PRED (bb, 0)); + while (EDGE_COUNT (bb->succs) != 0) + remove_edge (EDGE_SUCC (bb, 0)); + + if (dom_info_available_p (CDI_DOMINATORS)) + delete_from_dominance_info (CDI_DOMINATORS, bb); + if (dom_info_available_p (CDI_POST_DOMINATORS)) + delete_from_dominance_info (CDI_POST_DOMINATORS, bb); + + /* Remove the basic block from the array. */ + expunge_block (bb); +} + +/* Splits edge E and returns the newly created basic block. */ + +basic_block +split_edge (edge e) +{ + basic_block ret; + gcov_type count = e->count; + int freq = EDGE_FREQUENCY (e); + edge f; + bool irr = (e->flags & EDGE_IRREDUCIBLE_LOOP) != 0; + struct loop *loop; + basic_block src = e->src, dest = e->dest; + + if (!cfg_hooks->split_edge) + internal_error ("%s does not support split_edge", cfg_hooks->name); + + if (current_loops != NULL) + rescan_loop_exit (e, false, true); + + ret = cfg_hooks->split_edge (e); + ret->count = count; + ret->frequency = freq; + single_succ_edge (ret)->probability = REG_BR_PROB_BASE; + single_succ_edge (ret)->count = count; + + if (irr) + { + ret->flags |= BB_IRREDUCIBLE_LOOP; + single_pred_edge (ret)->flags |= EDGE_IRREDUCIBLE_LOOP; + single_succ_edge (ret)->flags |= EDGE_IRREDUCIBLE_LOOP; + } + + if (dom_info_available_p (CDI_DOMINATORS)) + set_immediate_dominator (CDI_DOMINATORS, ret, single_pred (ret)); + + if (dom_info_state (CDI_DOMINATORS) >= DOM_NO_FAST_QUERY) + { + /* There are two cases: + + If the immediate dominator of e->dest is not e->src, it + remains unchanged. + + If immediate dominator of e->dest is e->src, it may become + ret, provided that all other predecessors of e->dest are + dominated by e->dest. */ + + if (get_immediate_dominator (CDI_DOMINATORS, single_succ (ret)) + == single_pred (ret)) + { + edge_iterator ei; + FOR_EACH_EDGE (f, ei, single_succ (ret)->preds) + { + if (f == single_succ_edge (ret)) + continue; + + if (!dominated_by_p (CDI_DOMINATORS, f->src, + single_succ (ret))) + break; + } + + if (!f) + set_immediate_dominator (CDI_DOMINATORS, single_succ (ret), ret); + } + } + + if (current_loops != NULL) + { + loop = find_common_loop (src->loop_father, dest->loop_father); + add_bb_to_loop (ret, loop); + + if (loop->latch == src) + loop->latch = ret; + } + + return ret; +} + +/* Creates a new basic block just after the basic block AFTER. + HEAD and END are the first and the last statement belonging + to the block. If both are NULL, an empty block is created. */ + +basic_block +create_basic_block (void *head, void *end, basic_block after) +{ + basic_block ret; + + if (!cfg_hooks->create_basic_block) + internal_error ("%s does not support create_basic_block", cfg_hooks->name); + + ret = cfg_hooks->create_basic_block (head, end, after); + + if (dom_info_available_p (CDI_DOMINATORS)) + add_to_dominance_info (CDI_DOMINATORS, ret); + if (dom_info_available_p (CDI_POST_DOMINATORS)) + add_to_dominance_info (CDI_POST_DOMINATORS, ret); + + return ret; +} + +/* Creates an empty basic block just after basic block AFTER. */ + +basic_block +create_empty_bb (basic_block after) +{ + return create_basic_block (NULL, NULL, after); +} + +/* Checks whether we may merge blocks BB1 and BB2. */ + +bool +can_merge_blocks_p (basic_block bb1, basic_block bb2) +{ + bool ret; + + if (!cfg_hooks->can_merge_blocks_p) + internal_error ("%s does not support can_merge_blocks_p", cfg_hooks->name); + + ret = cfg_hooks->can_merge_blocks_p (bb1, bb2); + + return ret; +} + +void +predict_edge (edge e, enum br_predictor predictor, int probability) +{ + if (!cfg_hooks->predict_edge) + internal_error ("%s does not support predict_edge", cfg_hooks->name); + + cfg_hooks->predict_edge (e, predictor, probability); +} + +bool +predicted_by_p (const_basic_block bb, enum br_predictor predictor) +{ + if (!cfg_hooks->predict_edge) + internal_error ("%s does not support predicted_by_p", cfg_hooks->name); + + return cfg_hooks->predicted_by_p (bb, predictor); +} + +/* Merges basic block B into basic block A. */ + +void +merge_blocks (basic_block a, basic_block b) +{ + edge e; + edge_iterator ei; + + if (!cfg_hooks->merge_blocks) + internal_error ("%s does not support merge_blocks", cfg_hooks->name); + + cfg_hooks->merge_blocks (a, b); + + if (current_loops != NULL) + remove_bb_from_loops (b); + + /* Normally there should only be one successor of A and that is B, but + partway though the merge of blocks for conditional_execution we'll + be merging a TEST block with THEN and ELSE successors. Free the + whole lot of them and hope the caller knows what they're doing. */ + + while (EDGE_COUNT (a->succs) != 0) + remove_edge (EDGE_SUCC (a, 0)); + + /* Adjust the edges out of B for the new owner. */ + FOR_EACH_EDGE (e, ei, b->succs) + { + e->src = a; + if (current_loops != NULL) + rescan_loop_exit (e, true, false); + } + a->succs = b->succs; + a->flags |= b->flags; + + /* B hasn't quite yet ceased to exist. Attempt to prevent mishap. */ + b->preds = b->succs = NULL; + + if (dom_info_available_p (CDI_DOMINATORS)) + redirect_immediate_dominators (CDI_DOMINATORS, b, a); + + if (dom_info_available_p (CDI_DOMINATORS)) + delete_from_dominance_info (CDI_DOMINATORS, b); + if (dom_info_available_p (CDI_POST_DOMINATORS)) + delete_from_dominance_info (CDI_POST_DOMINATORS, b); + + expunge_block (b); +} + +/* Split BB into entry part and the rest (the rest is the newly created block). + Redirect those edges for that REDIRECT_EDGE_P returns true to the entry + part. Returns the edge connecting the entry part to the rest. */ + +edge +make_forwarder_block (basic_block bb, bool (*redirect_edge_p) (edge), + void (*new_bb_cbk) (basic_block)) +{ + edge e, fallthru; + edge_iterator ei; + basic_block dummy, jump; + struct loop *loop, *ploop, *cloop; + + if (!cfg_hooks->make_forwarder_block) + internal_error ("%s does not support make_forwarder_block", + cfg_hooks->name); + + fallthru = split_block_after_labels (bb); + dummy = fallthru->src; + bb = fallthru->dest; + + /* Redirect back edges we want to keep. */ + for (ei = ei_start (dummy->preds); (e = ei_safe_edge (ei)); ) + { + basic_block e_src; + + if (redirect_edge_p (e)) + { + ei_next (&ei); + continue; + } + + dummy->frequency -= EDGE_FREQUENCY (e); + dummy->count -= e->count; + if (dummy->frequency < 0) + dummy->frequency = 0; + if (dummy->count < 0) + dummy->count = 0; + fallthru->count -= e->count; + if (fallthru->count < 0) + fallthru->count = 0; + + e_src = e->src; + jump = redirect_edge_and_branch_force (e, bb); + if (jump != NULL) + { + /* If we redirected the loop latch edge, the JUMP block now acts like + the new latch of the loop. */ + if (current_loops != NULL + && dummy->loop_father != NULL + && dummy->loop_father->header == dummy + && dummy->loop_father->latch == e_src) + dummy->loop_father->latch = jump; + + if (new_bb_cbk != NULL) + new_bb_cbk (jump); + } + } + + if (dom_info_available_p (CDI_DOMINATORS)) + { + VEC (basic_block, heap) *doms_to_fix = VEC_alloc (basic_block, heap, 2); + VEC_quick_push (basic_block, doms_to_fix, dummy); + VEC_quick_push (basic_block, doms_to_fix, bb); + iterate_fix_dominators (CDI_DOMINATORS, doms_to_fix, false); + VEC_free (basic_block, heap, doms_to_fix); + } + + if (current_loops != NULL) + { + /* If we do not split a loop header, then both blocks belong to the + same loop. In case we split loop header and do not redirect the + latch edge to DUMMY, then DUMMY belongs to the outer loop, and + BB becomes the new header. If latch is not recorded for the loop, + we leave this updating on the caller (this may only happen during + loop analysis). */ + loop = dummy->loop_father; + if (loop->header == dummy + && loop->latch != NULL + && find_edge (loop->latch, dummy) == NULL) + { + remove_bb_from_loops (dummy); + loop->header = bb; + + cloop = loop; + FOR_EACH_EDGE (e, ei, dummy->preds) + { + cloop = find_common_loop (cloop, e->src->loop_father); + } + add_bb_to_loop (dummy, cloop); + } + + /* In case we split loop latch, update it. */ + for (ploop = loop; ploop; ploop = loop_outer (ploop)) + if (ploop->latch == dummy) + ploop->latch = bb; + } + + cfg_hooks->make_forwarder_block (fallthru); + + return fallthru; +} + +void +tidy_fallthru_edge (edge e) +{ + if (cfg_hooks->tidy_fallthru_edge) + cfg_hooks->tidy_fallthru_edge (e); +} + +/* Fix up edges that now fall through, or rather should now fall through + but previously required a jump around now deleted blocks. Simplify + the search by only examining blocks numerically adjacent, since this + is how find_basic_blocks created them. */ + +void +tidy_fallthru_edges (void) +{ + basic_block b, c; + + if (!cfg_hooks->tidy_fallthru_edge) + return; + + if (ENTRY_BLOCK_PTR->next_bb == EXIT_BLOCK_PTR) + return; + + FOR_BB_BETWEEN (b, ENTRY_BLOCK_PTR->next_bb, EXIT_BLOCK_PTR->prev_bb, next_bb) + { + edge s; + + c = b->next_bb; + + /* We care about simple conditional or unconditional jumps with + a single successor. + + If we had a conditional branch to the next instruction when + find_basic_blocks was called, then there will only be one + out edge for the block which ended with the conditional + branch (since we do not create duplicate edges). + + Furthermore, the edge will be marked as a fallthru because we + merge the flags for the duplicate edges. So we do not want to + check that the edge is not a FALLTHRU edge. */ + + if (single_succ_p (b)) + { + s = single_succ_edge (b); + if (! (s->flags & EDGE_COMPLEX) + && s->dest == c + && !find_reg_note (BB_END (b), REG_CROSSING_JUMP, NULL_RTX)) + tidy_fallthru_edge (s); + } + } +} + +/* Returns true if we can duplicate basic block BB. */ + +bool +can_duplicate_block_p (const_basic_block bb) +{ + if (!cfg_hooks->can_duplicate_block_p) + internal_error ("%s does not support can_duplicate_block_p", + cfg_hooks->name); + + if (bb == EXIT_BLOCK_PTR || bb == ENTRY_BLOCK_PTR) + return false; + + return cfg_hooks->can_duplicate_block_p (bb); +} + +/* Duplicates basic block BB and redirects edge E to it. Returns the + new basic block. The new basic block is placed after the basic block + AFTER. */ + +basic_block +duplicate_block (basic_block bb, edge e, basic_block after) +{ + edge s, n; + basic_block new_bb; + gcov_type new_count = e ? e->count : 0; + edge_iterator ei; + + if (!cfg_hooks->duplicate_block) + internal_error ("%s does not support duplicate_block", + cfg_hooks->name); + + if (bb->count < new_count) + new_count = bb->count; + +#ifdef ENABLE_CHECKING + gcc_assert (can_duplicate_block_p (bb)); +#endif + + new_bb = cfg_hooks->duplicate_block (bb); + if (after) + move_block_after (new_bb, after); + + new_bb->loop_depth = bb->loop_depth; + new_bb->flags = bb->flags; + FOR_EACH_EDGE (s, ei, bb->succs) + { + /* Since we are creating edges from a new block to successors + of another block (which therefore are known to be disjoint), there + is no need to actually check for duplicated edges. */ + n = unchecked_make_edge (new_bb, s->dest, s->flags); + n->probability = s->probability; + if (e && bb->count) + { + /* Take care for overflows! */ + n->count = s->count * (new_count * 10000 / bb->count) / 10000; + s->count -= n->count; + } + else + n->count = s->count; + n->aux = s->aux; + } + + if (e) + { + new_bb->count = new_count; + bb->count -= new_count; + + new_bb->frequency = EDGE_FREQUENCY (e); + bb->frequency -= EDGE_FREQUENCY (e); + + redirect_edge_and_branch_force (e, new_bb); + + if (bb->count < 0) + bb->count = 0; + if (bb->frequency < 0) + bb->frequency = 0; + } + else + { + new_bb->count = bb->count; + new_bb->frequency = bb->frequency; + } + + set_bb_original (new_bb, bb); + set_bb_copy (bb, new_bb); + + /* Add the new block to the copy of the loop of BB, or directly to the loop + of BB if the loop is not being copied. */ + if (current_loops != NULL) + { + struct loop *cloop = bb->loop_father; + struct loop *copy = get_loop_copy (cloop); + add_bb_to_loop (new_bb, copy ? copy : cloop); + } + + return new_bb; +} + +/* Return 1 if BB ends with a call, possibly followed by some + instructions that must stay with the call, 0 otherwise. */ + +bool +block_ends_with_call_p (basic_block bb) +{ + if (!cfg_hooks->block_ends_with_call_p) + internal_error ("%s does not support block_ends_with_call_p", cfg_hooks->name); + + return (cfg_hooks->block_ends_with_call_p) (bb); +} + +/* Return 1 if BB ends with a conditional branch, 0 otherwise. */ + +bool +block_ends_with_condjump_p (const_basic_block bb) +{ + if (!cfg_hooks->block_ends_with_condjump_p) + internal_error ("%s does not support block_ends_with_condjump_p", + cfg_hooks->name); + + return (cfg_hooks->block_ends_with_condjump_p) (bb); +} + +/* Add fake edges to the function exit for any non constant and non noreturn + calls, volatile inline assembly in the bitmap of blocks specified by + BLOCKS or to the whole CFG if BLOCKS is zero. Return the number of blocks + that were split. + + The goal is to expose cases in which entering a basic block does not imply + that all subsequent instructions must be executed. */ + +int +flow_call_edges_add (sbitmap blocks) +{ + if (!cfg_hooks->flow_call_edges_add) + internal_error ("%s does not support flow_call_edges_add", + cfg_hooks->name); + + return (cfg_hooks->flow_call_edges_add) (blocks); +} + +/* This function is called immediately after edge E is added to the + edge vector E->dest->preds. */ + +void +execute_on_growing_pred (edge e) +{ + if (cfg_hooks->execute_on_growing_pred) + cfg_hooks->execute_on_growing_pred (e); +} + +/* This function is called immediately before edge E is removed from + the edge vector E->dest->preds. */ + +void +execute_on_shrinking_pred (edge e) +{ + if (cfg_hooks->execute_on_shrinking_pred) + cfg_hooks->execute_on_shrinking_pred (e); +} + +/* This is used inside loop versioning when we want to insert + stmts/insns on the edges, which have a different behavior + in tree's and in RTL, so we made a CFG hook. */ +void +lv_flush_pending_stmts (edge e) +{ + if (cfg_hooks->flush_pending_stmts) + cfg_hooks->flush_pending_stmts (e); +} + +/* Loop versioning uses the duplicate_loop_to_header_edge to create + a new version of the loop basic-blocks, the parameters here are + exactly the same as in duplicate_loop_to_header_edge or + tree_duplicate_loop_to_header_edge; while in tree-ssa there is + additional work to maintain ssa information that's why there is + a need to call the tree_duplicate_loop_to_header_edge rather + than duplicate_loop_to_header_edge when we are in tree mode. */ +bool +cfg_hook_duplicate_loop_to_header_edge (struct loop *loop, edge e, + unsigned int ndupl, + sbitmap wont_exit, edge orig, + VEC (edge, heap) **to_remove, + int flags) +{ + gcc_assert (cfg_hooks->cfg_hook_duplicate_loop_to_header_edge); + return cfg_hooks->cfg_hook_duplicate_loop_to_header_edge (loop, e, + ndupl, wont_exit, + orig, to_remove, + flags); +} + +/* Conditional jumps are represented differently in trees and RTL, + this hook takes a basic block that is known to have a cond jump + at its end and extracts the taken and not taken edges out of it + and store it in E1 and E2 respectively. */ +void +extract_cond_bb_edges (basic_block b, edge *e1, edge *e2) +{ + gcc_assert (cfg_hooks->extract_cond_bb_edges); + cfg_hooks->extract_cond_bb_edges (b, e1, e2); +} + +/* Responsible for updating the ssa info (PHI nodes) on the + new condition basic block that guards the versioned loop. */ +void +lv_adjust_loop_header_phi (basic_block first, basic_block second, + basic_block new_block, edge e) +{ + if (cfg_hooks->lv_adjust_loop_header_phi) + cfg_hooks->lv_adjust_loop_header_phi (first, second, new_block, e); +} + +/* Conditions in trees and RTL are different so we need + a different handling when we add the condition to the + versioning code. */ +void +lv_add_condition_to_bb (basic_block first, basic_block second, + basic_block new_block, void *cond) +{ + gcc_assert (cfg_hooks->lv_add_condition_to_bb); + cfg_hooks->lv_add_condition_to_bb (first, second, new_block, cond); +}