X-Git-Url: http://git.sourceforge.jp/view?a=blobdiff_plain;f=gcc%2Fcfgbuild.c;h=453e65cf49537e0ae162fe61ba3ee51fdcd815b8;hb=f468be34b43786a757a41e1df6166e3dc42f803d;hp=69fcc15294b57598243a0cb216856865f2ec6047;hpb=5e69cae432c7787c9fc61e8b4ac3a04ddbc2b9b9;p=pf3gnuchains%2Fgcc-fork.git diff --git a/gcc/cfgbuild.c b/gcc/cfgbuild.c index 69fcc15294b..453e65cf495 100644 --- a/gcc/cfgbuild.c +++ b/gcc/cfgbuild.c @@ -1,6 +1,6 @@ /* Control flow graph building code for GNU compiler. Copyright (C) 1987, 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998, - 1999, 2000, 2001, 2002, 2003 Free Software Foundation, Inc. + 1999, 2000, 2001, 2002, 2003, 2004 Free Software Foundation, Inc. This file is part of GCC. @@ -48,30 +48,25 @@ Software Foundation, 59 Temple Place - Suite 330, Boston, MA #include "toplev.h" #include "timevar.h" -static int count_basic_blocks PARAMS ((rtx)); -static void find_basic_blocks_1 PARAMS ((rtx)); -static rtx find_label_refs PARAMS ((rtx, rtx)); -static void make_edges PARAMS ((rtx, basic_block, - basic_block, int)); -static void make_label_edge PARAMS ((sbitmap *, basic_block, - rtx, int)); -static void make_eh_edge PARAMS ((sbitmap *, basic_block, rtx)); -static void find_bb_boundaries PARAMS ((basic_block)); -static void compute_outgoing_frequencies PARAMS ((basic_block)); +static int count_basic_blocks (rtx); +static void find_basic_blocks_1 (rtx); +static void make_edges (basic_block, basic_block, int); +static void make_label_edge (sbitmap *, basic_block, rtx, int); +static void find_bb_boundaries (basic_block); +static void compute_outgoing_frequencies (basic_block); /* Return true if insn is something that should be contained inside basic block. */ bool -inside_basic_block_p (insn) - rtx insn; +inside_basic_block_p (rtx insn) { switch (GET_CODE (insn)) { case CODE_LABEL: /* Avoid creating of basic block for jumptables. */ return (NEXT_INSN (insn) == 0 - || GET_CODE (NEXT_INSN (insn)) != JUMP_INSN + || !JUMP_P (NEXT_INSN (insn)) || (GET_CODE (PATTERN (NEXT_INSN (insn))) != ADDR_VEC && GET_CODE (PATTERN (NEXT_INSN (insn))) != ADDR_DIFF_VEC)); @@ -88,7 +83,7 @@ inside_basic_block_p (insn) return false; default: - abort (); + gcc_unreachable (); } } @@ -96,8 +91,7 @@ inside_basic_block_p (insn) the basic block. */ bool -control_flow_insn_p (insn) - rtx insn; +control_flow_insn_p (rtx insn) { rtx note; @@ -113,6 +107,12 @@ control_flow_insn_p (insn) && GET_CODE (PATTERN (insn)) != ADDR_DIFF_VEC); case CALL_INSN: + /* Noreturn and sibling call instructions terminate the basic blocks + (but only if they happen unconditionally). */ + if ((SIBLING_CALL_P (insn) + || find_reg_note (insn, REG_NORETURN, 0)) + && GET_CODE (PATTERN (insn)) != COND_EXEC) + return true; /* Call insn may return to the nonlocal goto handler. */ return ((nonlocal_goto_handler_labels && (0 == (note = find_reg_note (insn, REG_EH_REGION, @@ -125,21 +125,20 @@ control_flow_insn_p (insn) return (flag_non_call_exceptions && can_throw_internal (insn)); case BARRIER: - /* It is nonsence to reach barrier when looking for the + /* It is nonsense to reach barrier when looking for the end of basic block, but before dead code is eliminated this may happen. */ return false; default: - abort (); + gcc_unreachable (); } } /* Count the basic blocks of the function. */ static int -count_basic_blocks (f) - rtx f; +count_basic_blocks (rtx f) { int count = 0; bool saw_insn = false; @@ -149,7 +148,7 @@ count_basic_blocks (f) { /* Code labels and barriers causes current basic block to be terminated at previous real insn. */ - if ((GET_CODE (insn) == CODE_LABEL || GET_CODE (insn) == BARRIER) + if ((LABEL_P (insn) || BARRIER_P (insn)) && saw_insn) count++, saw_insn = false; @@ -175,53 +174,6 @@ count_basic_blocks (f) return count; } - -/* Scan a list of insns for labels referred to other than by jumps. - This is used to scan the alternatives of a call placeholder. */ - -static rtx -find_label_refs (f, lvl) - rtx f; - rtx lvl; -{ - rtx insn; - - for (insn = f; insn; insn = NEXT_INSN (insn)) - if (INSN_P (insn) && GET_CODE (insn) != JUMP_INSN) - { - rtx note; - - /* Make a list of all labels referred to other than by jumps - (which just don't have the REG_LABEL notes). - - Make a special exception for labels followed by an ADDR*VEC, - as this would be a part of the tablejump setup code. - - Make a special exception to registers loaded with label - values just before jump insns that use them. */ - - for (note = REG_NOTES (insn); note; note = XEXP (note, 1)) - if (REG_NOTE_KIND (note) == REG_LABEL) - { - rtx lab = XEXP (note, 0), next; - - if ((next = next_nonnote_insn (lab)) != NULL - && GET_CODE (next) == JUMP_INSN - && (GET_CODE (PATTERN (next)) == ADDR_VEC - || GET_CODE (PATTERN (next)) == ADDR_DIFF_VEC)) - ; - else if (GET_CODE (lab) == NOTE) - ; - else if (GET_CODE (NEXT_INSN (insn)) == JUMP_INSN - && find_reg_note (NEXT_INSN (insn), REG_LABEL, lab)) - ; - else - lvl = alloc_EXPR_LIST (0, XEXP (note, 0), lvl); - } - } - - return lvl; -} /* Create an edge between two basic blocks. FLAGS are auxiliary information about the edge that is accumulated between calls. */ @@ -229,14 +181,9 @@ find_label_refs (f, lvl) /* Create an edge from a basic block to a label. */ static void -make_label_edge (edge_cache, src, label, flags) - sbitmap *edge_cache; - basic_block src; - rtx label; - int flags; +make_label_edge (sbitmap *edge_cache, basic_block src, rtx label, int flags) { - if (GET_CODE (label) != CODE_LABEL) - abort (); + gcc_assert (LABEL_P (label)); /* If the label was never emitted, this insn is junk, but avoid a crash trying to refer to BLOCK_FOR_INSN (label). This can happen @@ -251,13 +198,10 @@ make_label_edge (edge_cache, src, label, flags) /* Create the edges generated by INSN in REGION. */ -static void -make_eh_edge (edge_cache, src, insn) - sbitmap *edge_cache; - basic_block src; - rtx insn; +void +rtl_make_eh_edge (sbitmap *edge_cache, basic_block src, rtx insn) { - int is_call = GET_CODE (insn) == CALL_INSN ? EDGE_ABNORMAL_CALL : 0; + int is_call = CALL_P (insn) ? EDGE_ABNORMAL_CALL : 0; rtx handlers, i; handlers = reachable_handlers (insn); @@ -278,10 +222,7 @@ make_eh_edge (edge_cache, src, insn) the list of exception regions active at the end of the basic block. */ static void -make_edges (label_value_list, min, max, update_p) - rtx label_value_list; - basic_block min, max; - int update_p; +make_edges (basic_block min, basic_block max, int update_p) { basic_block bb; sbitmap *edge_cache = NULL; @@ -289,10 +230,19 @@ make_edges (label_value_list, min, max, update_p) /* Assume no computed jump; revise as we create edges. */ current_function_has_computed_jump = 0; + /* If we are partitioning hot and cold basic blocks into separate + sections, we cannot assume there is no computed jump (partitioning + sometimes requires the use of indirect jumps; see comments about + partitioning at the top of bb-reorder.c:partition_hot_cold_basic_blocks + for complete details). */ + + if (flag_reorder_blocks_and_partition) + current_function_has_computed_jump = 1; + /* Heavy use of computed goto in machine-generated code can lead to nearly fully-connected CFGs. In that case we spend a significant amount of time searching the edge lists for duplicates. */ - if (forced_labels || label_value_list || cfun->max_jumptable_ents > 100) + if (forced_labels || cfun->max_jumptable_ents > 100) { edge_cache = sbitmap_vector_alloc (last_basic_block, last_basic_block); sbitmap_vector_zero (edge_cache, last_basic_block); @@ -319,14 +269,16 @@ make_edges (label_value_list, min, max, update_p) rtx insn, x; enum rtx_code code; int force_fallthru = 0; + edge e; - if (GET_CODE (bb->head) == CODE_LABEL && LABEL_ALT_ENTRY_P (bb->head)) + if (LABEL_P (BB_HEAD (bb)) + && LABEL_ALT_ENTRY_P (BB_HEAD (bb))) cached_make_edge (NULL, ENTRY_BLOCK_PTR, bb, 0); /* Examine the last instruction of the block, and discover the ways we can leave the block. */ - insn = bb->end; + insn = BB_END (bb); code = GET_CODE (insn); /* A branch. */ @@ -336,7 +288,7 @@ make_edges (label_value_list, min, max, update_p) /* Recognize exception handling placeholders. */ if (GET_CODE (PATTERN (insn)) == RESX) - make_eh_edge (edge_cache, bb, insn); + rtl_make_eh_edge (edge_cache, bb, insn); /* Recognize a non-local goto as a branch outside the current function. */ @@ -376,14 +328,11 @@ make_edges (label_value_list, min, max, update_p) } /* If this is a computed jump, then mark it as reaching - everything on the label_value_list and forced_labels list. */ + everything on the forced_labels list. */ else if (computed_jump_p (insn)) { current_function_has_computed_jump = 1; - for (x = label_value_list; x; x = XEXP (x, 1)) - make_label_edge (edge_cache, bb, XEXP (x, 0), EDGE_ABNORMAL); - for (x = forced_labels; x; x = XEXP (x, 1)) make_label_edge (edge_cache, bb, XEXP (x, 0), EDGE_ABNORMAL); } @@ -395,8 +344,7 @@ make_edges (label_value_list, min, max, update_p) /* Otherwise, we have a plain conditional or unconditional jump. */ else { - if (! JUMP_LABEL (insn)) - abort (); + gcc_assert (JUMP_LABEL (insn)); make_label_edge (edge_cache, bb, JUMP_LABEL (insn), 0); } } @@ -407,7 +355,7 @@ make_edges (label_value_list, min, max, update_p) in the first place. */ if (code == CALL_INSN && SIBLING_CALL_P (insn)) cached_make_edge (edge_cache, bb, EXIT_BLOCK_PTR, - EDGE_ABNORMAL | EDGE_ABNORMAL_CALL); + EDGE_SIBCALL | EDGE_ABNORMAL); /* If this is a CALL_INSN, then mark it as reaching the active EH handler for this CALL_INSN. If we're handling non-call @@ -416,7 +364,7 @@ make_edges (label_value_list, min, max, update_p) else if (code == CALL_INSN || flag_non_call_exceptions) { /* Add any appropriate EH edges. */ - make_eh_edge (edge_cache, bb, insn); + rtl_make_eh_edge (edge_cache, bb, insn); if (code == CALL_INSN && nonlocal_goto_handler_labels) { @@ -440,8 +388,14 @@ make_edges (label_value_list, min, max, update_p) /* Find out if we can drop through to the next block. */ insn = NEXT_INSN (insn); + for (e = bb->succ; e; e = e->succ_next) + if (e->dest == EXIT_BLOCK_PTR && e->flags & EDGE_FALLTHRU) + { + insn = 0; + break; + } while (insn - && GET_CODE (insn) == NOTE + && NOTE_P (insn) && NOTE_LINE_NUMBER (insn) != NOTE_INSN_BASIC_BLOCK) insn = NEXT_INSN (insn); @@ -449,7 +403,7 @@ make_edges (label_value_list, min, max, update_p) cached_make_edge (edge_cache, bb, EXIT_BLOCK_PTR, EDGE_FALLTHRU); else if (bb->next_bb != EXIT_BLOCK_PTR) { - if (force_fallthru || insn == bb->next_bb->head) + if (force_fallthru || insn == BB_HEAD (bb->next_bb)) cached_make_edge (edge_cache, bb, bb->next_bb, EDGE_FALLTHRU); } } @@ -464,13 +418,10 @@ make_edges (label_value_list, min, max, update_p) will be used in make_edges for use with computed gotos. */ static void -find_basic_blocks_1 (f) - rtx f; +find_basic_blocks_1 (rtx f) { rtx insn, next; rtx bb_note = NULL_RTX; - rtx lvl = NULL_RTX; - rtx trll = NULL_RTX; rtx head = NULL_RTX; rtx end = NULL_RTX; basic_block prev = ENTRY_BLOCK_PTR; @@ -487,7 +438,7 @@ find_basic_blocks_1 (f) next = NEXT_INSN (insn); - if ((GET_CODE (insn) == CODE_LABEL || GET_CODE (insn) == BARRIER) + if ((LABEL_P (insn) || BARRIER_P (insn)) && head) { prev = create_basic_block_structure (head, end, bb_note, prev); @@ -531,57 +482,13 @@ find_basic_blocks_1 (f) case CODE_LABEL: case JUMP_INSN: + case CALL_INSN: case INSN: case BARRIER: break; - case CALL_INSN: - if (GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER) - { - /* Scan each of the alternatives for label refs. */ - lvl = find_label_refs (XEXP (PATTERN (insn), 0), lvl); - lvl = find_label_refs (XEXP (PATTERN (insn), 1), lvl); - lvl = find_label_refs (XEXP (PATTERN (insn), 2), lvl); - /* Record its tail recursion label, if any. */ - if (XEXP (PATTERN (insn), 3) != NULL_RTX) - trll = alloc_EXPR_LIST (0, XEXP (PATTERN (insn), 3), trll); - } - break; - default: - abort (); - } - - if (GET_CODE (insn) == INSN || GET_CODE (insn) == CALL_INSN) - { - rtx note; - - /* Make a list of all labels referred to other than by jumps. - - Make a special exception for labels followed by an ADDR*VEC, - as this would be a part of the tablejump setup code. - - Make a special exception to registers loaded with label - values just before jump insns that use them. */ - - for (note = REG_NOTES (insn); note; note = XEXP (note, 1)) - if (REG_NOTE_KIND (note) == REG_LABEL) - { - rtx lab = XEXP (note, 0), next; - - if ((next = next_nonnote_insn (lab)) != NULL - && GET_CODE (next) == JUMP_INSN - && (GET_CODE (PATTERN (next)) == ADDR_VEC - || GET_CODE (PATTERN (next)) == ADDR_DIFF_VEC)) - ; - else if (GET_CODE (lab) == NOTE) - ; - else if (GET_CODE (NEXT_INSN (insn)) == JUMP_INSN - && find_reg_note (NEXT_INSN (insn), REG_LABEL, lab)) - ; - else - lvl = alloc_EXPR_LIST (0, XEXP (note, 0), lvl); - } + gcc_unreachable (); } } @@ -590,11 +497,8 @@ find_basic_blocks_1 (f) else if (bb_note) delete_insn (bb_note); - if (last_basic_block != n_basic_blocks) - abort (); + gcc_assert (last_basic_block == n_basic_blocks); - label_value_list = lvl; - tail_recursion_label_list = trll; clear_aux_for_blocks (); } @@ -604,10 +508,8 @@ find_basic_blocks_1 (f) numbers in use. */ void -find_basic_blocks (f, nregs, file) - rtx f; - int nregs ATTRIBUTE_UNUSED; - FILE *file ATTRIBUTE_UNUSED; +find_basic_blocks (rtx f, int nregs ATTRIBUTE_UNUSED, + FILE *file ATTRIBUTE_UNUSED) { basic_block bb; @@ -622,9 +524,9 @@ find_basic_blocks (f, nregs, file) tag for reuse during create_basic_block, just in case some pass copies around basic block notes improperly. */ FOR_EACH_BB (bb) - bb->aux = NULL; + bb->aux = NULL; - VARRAY_FREE (basic_block_info); + basic_block_info = NULL; } n_basic_blocks = count_basic_blocks (f); @@ -644,8 +546,10 @@ find_basic_blocks (f, nregs, file) find_basic_blocks_1 (f); + profile_status = PROFILE_ABSENT; + /* Discover the edges of our cfg. */ - make_edges (label_value_list, ENTRY_BLOCK_PTR->next_bb, EXIT_BLOCK_PTR->prev_bb, 0); + make_edges (ENTRY_BLOCK_PTR->next_bb, EXIT_BLOCK_PTR->prev_bb, 0); /* Do very simple cleanup now, for the benefit of code that runs between here and cleanup_cfg, e.g. thread_prologue_and_epilogue_insns. */ @@ -667,18 +571,17 @@ enum state {BLOCK_NEW = 0, BLOCK_ORIGINAL, BLOCK_TO_SPLIT}; and create new basic blocks in the progress. */ static void -find_bb_boundaries (bb) - basic_block bb; +find_bb_boundaries (basic_block bb) { - rtx insn = bb->head; - rtx end = bb->end; + rtx insn = BB_HEAD (bb); + rtx end = BB_END (bb); rtx flow_transfer_insn = NULL_RTX; edge fallthru = NULL; - if (insn == bb->end) + if (insn == BB_END (bb)) return; - if (GET_CODE (insn) == CODE_LABEL) + if (LABEL_P (insn)) insn = NEXT_INSN (insn); /* Scan insn chain and try to find new basic block boundaries. */ @@ -691,7 +594,7 @@ find_bb_boundaries (bb) { fallthru = split_block (bb, PREV_INSN (insn)); if (flow_transfer_insn) - bb->end = flow_transfer_insn; + BB_END (bb) = flow_transfer_insn; bb = fallthru->dest; remove_edge (fallthru); @@ -705,7 +608,7 @@ find_bb_boundaries (bb) if (flow_transfer_insn && inside_basic_block_p (insn)) { fallthru = split_block (bb, PREV_INSN (insn)); - bb->end = flow_transfer_insn; + BB_END (bb) = flow_transfer_insn; bb = fallthru->dest; remove_edge (fallthru); flow_transfer_insn = NULL_RTX; @@ -722,7 +625,7 @@ find_bb_boundaries (bb) return and barrier, or possibly other sequence not behaving like ordinary jump, we need to take care and move basic block boundary. */ if (flow_transfer_insn) - bb->end = flow_transfer_insn; + BB_END (bb) = flow_transfer_insn; /* We've possibly replaced the conditional jump by conditional jump followed by cleanup at fallthru edge, so the outgoing edges may @@ -734,29 +637,27 @@ find_bb_boundaries (bb) and probabilities of outgoing edges. */ static void -compute_outgoing_frequencies (b) - basic_block b; +compute_outgoing_frequencies (basic_block b) { edge e, f; if (b->succ && b->succ->succ_next && !b->succ->succ_next->succ_next) { - rtx note = find_reg_note (b->end, REG_BR_PROB, NULL); + rtx note = find_reg_note (BB_END (b), REG_BR_PROB, NULL); int probability; - if (!note) - return; - - probability = INTVAL (XEXP (find_reg_note (b->end, - REG_BR_PROB, NULL), - 0)); - e = BRANCH_EDGE (b); - e->probability = probability; - e->count = ((b->count * probability + REG_BR_PROB_BASE / 2) - / REG_BR_PROB_BASE); - f = FALLTHRU_EDGE (b); - f->probability = REG_BR_PROB_BASE - probability; - f->count = b->count - e->count; + if (note) + { + probability = INTVAL (XEXP (note, 0)); + e = BRANCH_EDGE (b); + e->probability = probability; + e->count = ((b->count * probability + REG_BR_PROB_BASE / 2) + / REG_BR_PROB_BASE); + f = FALLTHRU_EDGE (b); + f->probability = REG_BR_PROB_BASE - probability; + f->count = b->count - e->count; + return; + } } if (b->succ && !b->succ->succ_next) @@ -764,15 +665,20 @@ compute_outgoing_frequencies (b) e = b->succ; e->probability = REG_BR_PROB_BASE; e->count = b->count; + return; } + guess_outgoing_edge_probabilities (b); + if (b->count) + for (e = b->succ; e; e = e->succ_next) + e->count = ((b->count * e->probability + REG_BR_PROB_BASE / 2) + / REG_BR_PROB_BASE); } /* Assume that someone emitted code with control flow instructions to the basic block. Update the data structure. */ void -find_many_sub_basic_blocks (blocks) - sbitmap blocks; +find_many_sub_basic_blocks (sbitmap blocks) { basic_block bb, min, max; @@ -795,29 +701,30 @@ find_many_sub_basic_blocks (blocks) /* Now re-scan and wire in all edges. This expect simple (conditional) jumps at the end of each new basic blocks. */ - make_edges (NULL, min, max, 1); + make_edges (min, max, 1); /* Update branch probabilities. Expect only (un)conditional jumps to be created with only the forward edges. */ - FOR_BB_BETWEEN (bb, min, max->next_bb, next_bb) - { - edge e; + if (profile_status != PROFILE_ABSENT) + FOR_BB_BETWEEN (bb, min, max->next_bb, next_bb) + { + edge e; - if (STATE (bb) == BLOCK_ORIGINAL) - continue; - if (STATE (bb) == BLOCK_NEW) - { - bb->count = 0; - bb->frequency = 0; - for (e = bb->pred; e; e = e->pred_next) - { - bb->count += e->count; - bb->frequency += EDGE_FREQUENCY (e); - } - } + if (STATE (bb) == BLOCK_ORIGINAL) + continue; + if (STATE (bb) == BLOCK_NEW) + { + bb->count = 0; + bb->frequency = 0; + for (e = bb->pred; e; e = e->pred_next) + { + bb->count += e->count; + bb->frequency += EDGE_FREQUENCY (e); + } + } - compute_outgoing_frequencies (bb); - } + compute_outgoing_frequencies (bb); + } FOR_EACH_BB (bb) SET_STATE (bb, 0); @@ -826,8 +733,7 @@ find_many_sub_basic_blocks (blocks) /* Like above but for single basic block only. */ void -find_sub_basic_blocks (bb) - basic_block bb; +find_sub_basic_blocks (basic_block bb) { basic_block min, max, b; basic_block next = bb->next_bb; @@ -838,7 +744,7 @@ find_sub_basic_blocks (bb) /* Now re-scan and wire in all edges. This expect simple (conditional) jumps at the end of each new basic blocks. */ - make_edges (NULL, min, max, 1); + make_edges (min, max, 1); /* Update branch probabilities. Expect only (un)conditional jumps to be created with only the forward edges. */