X-Git-Url: http://git.sourceforge.jp/view?a=blobdiff_plain;f=gcc%2Fcfgbuild.c;h=d87d6d35de56b45a7007b3d562210a4596fdea4e;hb=79f86a88dadbf33f49759c47f5ddc1c2b709e03e;hp=7f3e72b9ff50486fe560ec4ef73f523fb70612f8;hpb=cd6dccd365b9354fc13cdb1604ff2a71e610072b;p=pf3gnuchains%2Fgcc-fork.git diff --git a/gcc/cfgbuild.c b/gcc/cfgbuild.c index 7f3e72b9ff5..d87d6d35de5 100644 --- a/gcc/cfgbuild.c +++ b/gcc/cfgbuild.c @@ -28,9 +28,7 @@ Software Foundation, 59 Temple Place - Suite 330, Boston, MA Available functionality: - CFG construction - find_basic_blocks - - Local CFG construction - find_sub_basic_blocks */ + find_basic_blocks */ #include "config.h" #include "system.h" @@ -51,7 +49,7 @@ Software Foundation, 59 Temple Place - Suite 330, Boston, MA 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 make_label_edge (sbitmap, basic_block, rtx, int); static void find_bb_boundaries (basic_block); static void compute_outgoing_frequencies (basic_block); @@ -181,7 +179,7 @@ count_basic_blocks (rtx f) /* Create an edge from a basic block to a label. */ static void -make_label_edge (sbitmap *edge_cache, basic_block src, rtx label, int flags) +make_label_edge (sbitmap edge_cache, basic_block src, rtx label, int flags) { gcc_assert (LABEL_P (label)); @@ -199,7 +197,7 @@ make_label_edge (sbitmap *edge_cache, basic_block src, rtx label, int flags) /* Create the edges generated by INSN in REGION. */ void -rtl_make_eh_edge (sbitmap *edge_cache, basic_block src, rtx insn) +rtl_make_eh_edge (sbitmap edge_cache, basic_block src, rtx insn) { int is_call = CALL_P (insn) ? EDGE_ABNORMAL_CALL : 0; rtx handlers, i; @@ -213,51 +211,76 @@ rtl_make_eh_edge (sbitmap *edge_cache, basic_block src, rtx insn) free_INSN_LIST_list (&handlers); } -/* Identify the edges between basic blocks MIN to MAX. +/* States of basic block as seen by find_many_sub_basic_blocks. */ +enum state { + /* Basic blocks created via split_block belong to this state. + make_edges will examine these basic blocks to see if we need to + create edges going out of them. */ + BLOCK_NEW = 0, - NONLOCAL_LABEL_LIST is a list of non-local labels in the function. Blocks - that are otherwise unreachable may be reachable with a non-local goto. + /* Basic blocks that do not need examining belong to this state. + These blocks will be left intact. In particular, make_edges will + not create edges going out of these basic blocks. */ + BLOCK_ORIGINAL, - BB_EH_END is an array indexed by basic block number in which we record - the list of exception regions active at the end of the basic block. */ + /* Basic blocks that may need splitting (due to a label appearing in + the middle, etc) belong to this state. After splitting them, + make_edges will create edges going out of them as needed. */ + BLOCK_TO_SPLIT +}; + +#define STATE(BB) (enum state) ((size_t) (BB)->aux) +#define SET_STATE(BB, STATE) ((BB)->aux = (void *) (size_t) (STATE)) + +/* Used internally by purge_dead_tablejump_edges, ORed into state. */ +#define BLOCK_USED_BY_TABLEJUMP 32 +#define FULL_STATE(BB) ((size_t) (BB)->aux) + +/* Identify the edges going out of basic blocks between MIN and MAX, + inclusive, that have their states set to BLOCK_NEW or + BLOCK_TO_SPLIT. + + UPDATE_P should be nonzero if we are updating CFG and zero if we + are building CFG from scratch. */ static void make_edges (basic_block min, basic_block max, int update_p) { basic_block bb; - sbitmap *edge_cache = NULL; + sbitmap edge_cache = NULL; /* 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 || cfun->max_jumptable_ents > 100) - { - edge_cache = sbitmap_vector_alloc (last_basic_block, last_basic_block); - sbitmap_vector_zero (edge_cache, last_basic_block); - - if (update_p) - FOR_BB_BETWEEN (bb, min, max->next_bb, next_bb) - { - edge e; - edge_iterator ei; - - FOR_EACH_EDGE (e, ei, bb->succs) - if (e->dest != EXIT_BLOCK_PTR) - SET_BIT (edge_cache[bb->index], e->dest->index); - } - } + edge_cache = sbitmap_alloc (last_basic_block); /* By nature of the way these get numbered, ENTRY_BLOCK_PTR->next_bb block is always the entry. */ if (min == ENTRY_BLOCK_PTR->next_bb) - cached_make_edge (edge_cache, ENTRY_BLOCK_PTR, min, - EDGE_FALLTHRU); + make_edge (ENTRY_BLOCK_PTR, min, EDGE_FALLTHRU); FOR_BB_BETWEEN (bb, min, max->next_bb, next_bb) { rtx insn, x; enum rtx_code code; edge e; + edge_iterator ei; + + if (STATE (bb) == BLOCK_ORIGINAL) + continue; + + /* If we have an edge cache, cache edges going out of BB. */ + if (edge_cache) + { + sbitmap_zero (edge_cache); + if (update_p) + { + FOR_EACH_EDGE (e, ei, bb->succs) + if (e->dest != EXIT_BLOCK_PTR) + SET_BIT (edge_cache, e->dest->index); + } + } if (LABEL_P (BB_HEAD (bb)) && LABEL_ALT_ENTRY_P (BB_HEAD (bb))) @@ -482,12 +505,10 @@ find_basic_blocks_1 (rtx f) /* Find basic blocks of the current function. - F is the first insn of the function and NREGS the number of register - numbers in use. */ + F is the first insn of the function. */ void -find_basic_blocks (rtx f, int nregs ATTRIBUTE_UNUSED, - FILE *file ATTRIBUTE_UNUSED) +find_basic_blocks (rtx f) { basic_block bb; @@ -526,6 +547,10 @@ find_basic_blocks (rtx f, int nregs ATTRIBUTE_UNUSED, profile_status = PROFILE_ABSENT; + /* Tell make_edges to examine every block for out-going edges. */ + FOR_EACH_BB (bb) + SET_STATE (bb, BLOCK_NEW); + /* Discover the edges of our cfg. */ make_edges (ENTRY_BLOCK_PTR->next_bb, EXIT_BLOCK_PTR->prev_bb, 0); @@ -539,16 +564,6 @@ find_basic_blocks (rtx f, int nregs ATTRIBUTE_UNUSED, timevar_pop (TV_CFG); } -/* State of basic block as seen by find_sub_basic_blocks. */ -enum state {BLOCK_NEW = 0, BLOCK_ORIGINAL, BLOCK_TO_SPLIT}; - -#define STATE(BB) (enum state) ((size_t) (BB)->aux) -#define SET_STATE(BB, STATE) ((BB)->aux = (void *) (size_t) (STATE)) - -/* Used internally by purge_dead_tablejump_edges, ORed into state. */ -#define BLOCK_USED_BY_TABLEJUMP 32 -#define FULL_STATE(BB) ((size_t) (BB)->aux) - static void mark_tablejump_edge (rtx label) { @@ -703,9 +718,9 @@ compute_outgoing_frequencies (basic_block b) } } - if (EDGE_COUNT (b->succs) == 1) + if (single_succ_p (b)) { - e = EDGE_SUCC (b, 0); + e = single_succ_edge (b); e->probability = REG_BR_PROB_BASE; e->count = b->count; return; @@ -717,8 +732,9 @@ compute_outgoing_frequencies (basic_block b) / REG_BR_PROB_BASE); } -/* Assume that someone emitted code with control flow instructions to the - basic block. Update the data structure. */ +/* Assume that some pass has inserted labels or control flow + instructions within a basic block. Split basic blocks as needed + and create edges. */ void find_many_sub_basic_blocks (sbitmap blocks) @@ -773,41 +789,3 @@ find_many_sub_basic_blocks (sbitmap blocks) FOR_EACH_BB (bb) SET_STATE (bb, 0); } - -/* Like above but for single basic block only. */ - -void -find_sub_basic_blocks (basic_block bb) -{ - basic_block min, max, b; - basic_block next = bb->next_bb; - - min = bb; - find_bb_boundaries (bb); - max = next->prev_bb; - - /* Now re-scan and wire in all edges. This expect simple (conditional) - jumps at the end of each new basic blocks. */ - make_edges (min, max, 1); - - /* Update branch probabilities. Expect only (un)conditional jumps - to be created with only the forward edges. */ - FOR_BB_BETWEEN (b, min, max->next_bb, next_bb) - { - edge e; - edge_iterator ei; - - if (b != min) - { - b->count = 0; - b->frequency = 0; - FOR_EACH_EDGE (e, ei, b->preds) - { - b->count += e->count; - b->frequency += EDGE_FREQUENCY (e); - } - } - - compute_outgoing_frequencies (b); - } -}