X-Git-Url: http://git.sourceforge.jp/view?a=blobdiff_plain;f=gcc%2Ftree-ssa.c;h=f7306b1833dda5b7bc8f48b6c8fc0089c65a80f4;hb=9ec0fbe12f5d88044672d79ff164eff1d2ec3f94;hp=9346d6cf7065425debbaf304d132a92db5073dff;hpb=a9fc9109fc2ba4fea83e94f39914133e2c78ab83;p=pf3gnuchains%2Fgcc-fork.git diff --git a/gcc/tree-ssa.c b/gcc/tree-ssa.c index 9346d6cf706..f7306b1833d 100644 --- a/gcc/tree-ssa.c +++ b/gcc/tree-ssa.c @@ -1,11 +1,11 @@ /* Miscellaneous SSA utility functions. - Copyright (C) 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc. + Copyright (C) 2001, 2002, 2003, 2004, 2005, 2007 Free Software Foundation, Inc. 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, @@ -14,9 +14,8 @@ 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" @@ -31,7 +30,6 @@ Boston, MA 02111-1307, USA. */ #include "hard-reg-set.h" #include "basic-block.h" #include "output.h" -#include "errors.h" #include "expr.h" #include "function.h" #include "diagnostic.h" @@ -45,59 +43,177 @@ Boston, MA 02111-1307, USA. */ #include "hashtab.h" #include "tree-dump.h" #include "tree-pass.h" +#include "toplev.h" + +/* Pointer map of variable mappings, keyed by edge. */ +static struct pointer_map_t *edge_var_maps; + + +/* Add a mapping with PHI RESULT and PHI DEF associated with edge E. */ + +void +redirect_edge_var_map_add (edge e, tree result, tree def) +{ + void **slot; + edge_var_map_vector old_head, head; + edge_var_map new_node; + + if (edge_var_maps == NULL) + edge_var_maps = pointer_map_create (); + + slot = pointer_map_insert (edge_var_maps, e); + old_head = head = *slot; + if (!head) + { + head = VEC_alloc (edge_var_map, heap, 5); + *slot = head; + } + new_node.def = def; + new_node.result = result; + + VEC_safe_push (edge_var_map, heap, head, &new_node); + if (old_head != head) + { + /* The push did some reallocation. Update the pointer map. */ + *slot = head; + } +} + + +/* Clear the var mappings in edge E. */ + +void +redirect_edge_var_map_clear (edge e) +{ + void **slot; + edge_var_map_vector head; + + if (!edge_var_maps) + return; + + slot = pointer_map_contains (edge_var_maps, e); + + if (slot) + { + head = *slot; + VEC_free (edge_var_map, heap, head); + *slot = NULL; + } +} + + +/* Duplicate the redirected var mappings in OLDE in NEWE. + + Since we can't remove a mapping, let's just duplicate it. This assumes a + pointer_map can have multiple edges mapping to the same var_map (many to + one mapping), since we don't remove the previous mappings. */ + +void +redirect_edge_var_map_dup (edge newe, edge olde) +{ + void **new_slot, **old_slot; edge_var_map_vector head; + + if (!edge_var_maps) + return; + + new_slot = pointer_map_insert (edge_var_maps, newe); + old_slot = pointer_map_contains (edge_var_maps, olde); + if (!old_slot) + return; + head = *old_slot; + + if (head) + *new_slot = VEC_copy (edge_var_map, heap, head); + else + *new_slot = VEC_alloc (edge_var_map, heap, 5); +} + + +/* Return the varable mappings for a given edge. If there is none, return + NULL. */ + +edge_var_map_vector +redirect_edge_var_map_vector (edge e) +{ + void **slot; + + /* Hey, what kind of idiot would... you'd be surprised. */ + if (!edge_var_maps) + return NULL; + + slot = pointer_map_contains (edge_var_maps, e); + if (!slot) + return NULL; + + return (edge_var_map_vector) *slot; +} + + +/* Clear the edge variable mappings. */ + +void +redirect_edge_var_map_destroy (void) +{ + if (edge_var_maps) + { + pointer_map_destroy (edge_var_maps); + edge_var_maps = NULL; + } +} + /* Remove the corresponding arguments from the PHI nodes in E's destination block and redirect it to DEST. Return redirected edge. - The list of removed arguments is stored in PENDING_STMT (e). */ + The list of removed arguments is stored in a vector accessed + through edge_var_maps. */ edge ssa_redirect_edge (edge e, basic_block dest) { - tree phi, next; - tree list = NULL, *last = &list; - tree src, dst, node; + tree phi; + + redirect_edge_var_map_clear (e); /* Remove the appropriate PHI arguments in E's destination block. */ - for (phi = phi_nodes (e->dest); phi; phi = next) + for (phi = phi_nodes (e->dest); phi; phi = PHI_CHAIN (phi)) { - next = PHI_CHAIN (phi); + tree def = PHI_ARG_DEF (phi, e->dest_idx); - if (PHI_ARG_DEF (phi, e->dest_idx) == NULL_TREE) + if (def == NULL_TREE) continue; - src = PHI_ARG_DEF (phi, e->dest_idx); - dst = PHI_RESULT (phi); - node = build_tree_list (dst, src); - *last = node; - last = &TREE_CHAIN (node); + redirect_edge_var_map_add (e, PHI_RESULT (phi), def); } e = redirect_edge_succ_nodup (e, dest); - PENDING_STMT (e) = list; return e; } -/* Add PHI arguments queued in PENDINT_STMT list on edge E to edge +/* Add PHI arguments queued in PENDING_STMT list on edge E to edge E->dest. */ void flush_pending_stmts (edge e) { - tree phi, arg; + tree phi; + edge_var_map_vector v; + edge_var_map *vm; + int i; - if (!PENDING_STMT (e)) + v = redirect_edge_var_map_vector (e); + if (!v) return; - for (phi = phi_nodes (e->dest), arg = PENDING_STMT (e); - phi; - phi = PHI_CHAIN (phi), arg = TREE_CHAIN (arg)) + for (phi = phi_nodes (e->dest), i = 0; + phi && VEC_iterate (edge_var_map, v, i, vm); + phi = PHI_CHAIN (phi), i++) { - tree def = TREE_VALUE (arg); + tree def = redirect_edge_var_map_def (vm); add_phi_arg (phi, def, e); } - PENDING_STMT (e) = NULL; + redirect_edge_var_map_clear (e); } /* Return true if SSA_NAME is malformed and mark it visited. @@ -110,31 +226,45 @@ verify_ssa_name (tree ssa_name, bool is_virtual) { if (TREE_CODE (ssa_name) != SSA_NAME) { - error ("Expected an SSA_NAME object"); + error ("expected an SSA_NAME object"); return true; } if (TREE_TYPE (ssa_name) != TREE_TYPE (SSA_NAME_VAR (ssa_name))) { - error ("Type mismatch between an SSA_NAME and its symbol."); + error ("type mismatch between an SSA_NAME and its symbol"); return true; } if (SSA_NAME_IN_FREE_LIST (ssa_name)) { - error ("Found an SSA_NAME that had been released into the free pool"); + error ("found an SSA_NAME that had been released into the free pool"); return true; } if (is_virtual && is_gimple_reg (ssa_name)) { - error ("Found a virtual definition for a GIMPLE register"); + error ("found a virtual definition for a GIMPLE register"); return true; } if (!is_virtual && !is_gimple_reg (ssa_name)) { - error ("Found a real definition for a non-register"); + error ("found a real definition for a non-register"); + return true; + } + + if (is_virtual && var_ann (SSA_NAME_VAR (ssa_name)) + && get_subvars_for_var (SSA_NAME_VAR (ssa_name)) != NULL) + { + error ("found real variable when subvariables should have appeared"); + return true; + } + + if (SSA_NAME_IS_DEFAULT_DEF (ssa_name) + && !IS_EMPTY_STMT (SSA_NAME_DEF_STMT (ssa_name))) + { + error ("found a default name with a non-empty defining statement"); return true; } @@ -151,8 +281,7 @@ verify_ssa_name (tree ssa_name, bool is_virtual) it means that the block in that array slot contains the definition of SSA_NAME. - IS_VIRTUAL is true if SSA_NAME is created by a V_MAY_DEF or a - V_MUST_DEF. */ + IS_VIRTUAL is true if SSA_NAME is created by a VDEF. */ static bool verify_def (basic_block bb, basic_block *definition_block, tree ssa_name, @@ -203,34 +332,34 @@ err: is flowing through an abnormal edge (only used when checking PHI arguments). - IS_VIRTUAL is true if SSA_NAME is created by a V_MAY_DEF or a - V_MUST_DEF. - If NAMES_DEFINED_IN_BB is not NULL, it contains a bitmap of ssa names that are defined before STMT in basic block BB. */ static bool -verify_use (basic_block bb, basic_block def_bb, tree ssa_name, - tree stmt, bool check_abnormal, bool is_virtual, - bitmap names_defined_in_bb) +verify_use (basic_block bb, basic_block def_bb, use_operand_p use_p, + tree stmt, bool check_abnormal, bitmap names_defined_in_bb) { bool err = false; + tree ssa_name = USE_FROM_PTR (use_p); + + if (!TREE_VISITED (ssa_name)) + if (verify_imm_links (stderr, ssa_name)) + err = true; - err = verify_ssa_name (ssa_name, is_virtual); TREE_VISITED (ssa_name) = 1; if (IS_EMPTY_STMT (SSA_NAME_DEF_STMT (ssa_name)) - && var_ann (SSA_NAME_VAR (ssa_name))->default_def == ssa_name) + && SSA_NAME_IS_DEFAULT_DEF (ssa_name)) ; /* Default definitions have empty statements. Nothing to do. */ else if (!def_bb) { - error ("Missing definition"); + error ("missing definition"); err = true; } else if (bb != def_bb && !dominated_by_p (CDI_DOMINATORS, bb, def_bb)) { - error ("Definition in block %i does not dominate use in block %i", + error ("definition in block %i does not dominate use in block %i", def_bb->index, bb->index); err = true; } @@ -238,7 +367,7 @@ verify_use (basic_block bb, basic_block def_bb, tree ssa_name, && names_defined_in_bb != NULL && !bitmap_bit_p (names_defined_in_bb, SSA_NAME_VERSION (ssa_name))) { - error ("Definition in block %i follows the use", def_bb->index); + error ("definition in block %i follows the use", def_bb->index); err = true; } @@ -249,11 +378,32 @@ verify_use (basic_block bb, basic_block def_bb, tree ssa_name, err = true; } + /* Make sure the use is in an appropriate list by checking the previous + element to make sure it's the same. */ + if (use_p->prev == NULL) + { + error ("no immediate_use list"); + err = true; + } + else + { + tree listvar ; + if (use_p->prev->use == NULL) + listvar = use_p->prev->stmt; + else + listvar = USE_FROM_PTR (use_p->prev); + if (listvar != ssa_name) + { + error ("wrong immediate use list"); + err = true; + } + } + if (err) { fprintf (stderr, "for SSA_NAME: "); print_generic_expr (stderr, ssa_name, TDF_VOPS); - fprintf (stderr, "in statement:\n"); + fprintf (stderr, " in statement:\n"); print_generic_stmt (stderr, stmt, TDF_VOPS); } @@ -264,9 +414,10 @@ verify_use (basic_block bb, basic_block def_bb, tree ssa_name, /* Return true if any of the arguments for PHI node PHI at block BB is malformed. - DEFINITION_BLOCK is an array of basic blocks indexed by SSA_NAME version - numbers. If DEFINITION_BLOCK[SSA_NAME_VERSION] is set, it means that the - block in that array slot contains the definition of SSA_NAME. */ + DEFINITION_BLOCK is an array of basic blocks indexed by SSA_NAME + version numbers. If DEFINITION_BLOCK[SSA_NAME_VERSION] is set, + it means that the block in that array slot contains the + definition of SSA_NAME. */ static bool verify_phi_args (tree phi, basic_block bb, basic_block *definition_block) @@ -277,20 +428,21 @@ verify_phi_args (tree phi, basic_block bb, basic_block *definition_block) if (EDGE_COUNT (bb->preds) != phi_num_args) { - error ("Incoming edge count does not match number of PHI arguments\n"); + error ("incoming edge count does not match number of PHI arguments"); err = true; goto error; } for (i = 0; i < phi_num_args; i++) { - tree op = PHI_ARG_DEF (phi, i); + use_operand_p op_p = PHI_ARG_DEF_PTR (phi, i); + tree op = USE_FROM_PTR (op_p); e = EDGE_PRED (bb, i); if (op == NULL_TREE) { - error ("PHI argument is missing for edge %d->%d\n", + error ("PHI argument is missing for edge %d->%d", e->src->index, e->dest->index); err = true; @@ -304,15 +456,16 @@ verify_phi_args (tree phi, basic_block bb, basic_block *definition_block) } if (TREE_CODE (op) == SSA_NAME) - err = verify_use (e->src, definition_block[SSA_NAME_VERSION (op)], op, - phi, e->flags & EDGE_ABNORMAL, - !is_gimple_reg (PHI_RESULT (phi)), - NULL); + { + err = verify_ssa_name (op, !is_gimple_reg (PHI_RESULT (phi))); + err |= verify_use (e->src, definition_block[SSA_NAME_VERSION (op)], + op_p, phi, e->flags & EDGE_ABNORMAL, NULL); + } if (e->dest != bb) { - error ("Wrong edge %d->%d for PHI argument\n", - e->src->index, e->dest->index, bb->index); + error ("wrong edge %d->%d for PHI argument", + e->src->index, e->dest->index); err = true; } @@ -328,7 +481,7 @@ error: if (err) { fprintf (stderr, "for PHI node\n"); - print_generic_stmt (stderr, phi, TDF_VOPS); + print_generic_stmt (stderr, phi, TDF_VOPS|TDF_MEMSYMS); } @@ -339,57 +492,40 @@ error: static void verify_flow_insensitive_alias_info (void) { - size_t i; tree var; - bitmap visited = BITMAP_ALLOC (NULL); + referenced_var_iterator rvi; - for (i = 0; i < num_referenced_vars; i++) + FOR_EACH_REFERENCED_VAR (var, rvi) { - size_t j; - var_ann_t ann; - varray_type may_aliases; + unsigned int j; + bitmap aliases; + tree alias; + bitmap_iterator bi; - var = referenced_var (i); - ann = var_ann (var); - may_aliases = ann->may_aliases; + if (!MTAG_P (var) || !MTAG_ALIASES (var)) + continue; + + aliases = MTAG_ALIASES (var); - for (j = 0; may_aliases && j < VARRAY_ACTIVE_SIZE (may_aliases); j++) + EXECUTE_IF_SET_IN_BITMAP (aliases, 0, j, bi) { - tree alias = VARRAY_TREE (may_aliases, j); - - bitmap_set_bit (visited, var_ann (alias)->uid); + alias = referenced_var (j); - if (!may_be_aliased (alias)) + if (TREE_CODE (alias) != MEMORY_PARTITION_TAG + && !may_be_aliased (alias)) { - error ("Non-addressable variable inside an alias set."); + error ("non-addressable variable inside an alias set"); debug_variable (alias); goto err; } } } - for (i = 0; i < num_referenced_vars; i++) - { - var_ann_t ann; - - var = referenced_var (i); - ann = var_ann (var); - - if (ann->mem_tag_kind == NOT_A_TAG - && ann->is_alias_tag - && !bitmap_bit_p (visited, ann->uid)) - { - error ("Addressable variable that is an alias tag but is not in any alias set."); - goto err; - } - } - - BITMAP_FREE (visited); return; err: debug_variable (var); - internal_error ("verify_flow_insensitive_alias_info failed."); + internal_error ("verify_flow_insensitive_alias_info failed"); } @@ -429,26 +565,30 @@ verify_flow_sensitive_alias_info (void) continue; ann = var_ann (var); - if (pi->is_dereferenced && !pi->name_mem_tag && !ann->type_mem_tag) + if (pi->is_dereferenced && !pi->name_mem_tag && !ann->symbol_mem_tag) { - error ("Dereferenced pointers should have a name or a type tag"); + error ("dereferenced pointers should have a name or a symbol tag"); goto err; } if (pi->name_mem_tag - && !pi->pt_malloc && (pi->pt_vars == NULL || bitmap_empty_p (pi->pt_vars))) { - error ("Pointers with a memory tag, should have points-to sets or point to malloc"); + error ("pointers with a memory tag, should have points-to sets"); goto err; } - if (pi->value_escapes_p - && pi->name_mem_tag - && !is_call_clobbered (pi->name_mem_tag)) + if (pi->value_escapes_p && pi->name_mem_tag) { - error ("Pointer escapes but its name tag is not call-clobbered."); - goto err; + tree t = memory_partition (pi->name_mem_tag); + if (t == NULL_TREE) + t = pi->name_mem_tag; + + if (!is_call_clobbered (t)) + { + error ("pointer escapes but its name tag is not call-clobbered"); + goto err; + } } } @@ -456,128 +596,108 @@ verify_flow_sensitive_alias_info (void) err: debug_variable (ptr); - internal_error ("verify_flow_sensitive_alias_info failed."); + internal_error ("verify_flow_sensitive_alias_info failed"); } -DEF_VEC_MALLOC_P (bitmap); - -/* Verify that all name tags have different points to sets. - This algorithm takes advantage of the fact that every variable with the - same name tag must have the same points-to set. - So we check a single variable for each name tag, and verify that its - points-to set is different from every other points-to set for other name - tags. - Additionally, given a pointer P_i with name tag NMT and type tag - TMT, this function verified the alias set of TMT is a superset of - the alias set of NMT. */ +/* Verify the consistency of call clobbering information. */ static void -verify_name_tags (void) +verify_call_clobbering (void) { - size_t i; - size_t j; - bitmap first, second; - VEC (tree) *name_tag_reps = NULL; - VEC (bitmap) *pt_vars_for_reps = NULL; - bitmap type_aliases = BITMAP_ALLOC (NULL); - - /* First we compute the name tag representatives and their points-to sets. */ - for (i = 0; i < num_ssa_names; i++) + unsigned int i; + bitmap_iterator bi; + tree var; + referenced_var_iterator rvi; + + /* At all times, the result of the call_clobbered flag should + match the result of the call_clobbered_vars bitmap. Verify both + that everything in call_clobbered_vars is marked + call_clobbered, and that everything marked + call_clobbered is in call_clobbered_vars. */ + EXECUTE_IF_SET_IN_BITMAP (gimple_call_clobbered_vars (cfun), 0, i, bi) { - struct ptr_info_def *pi; - tree tmt, ptr = ssa_name (i); - - if (ptr == NULL_TREE) - continue; - - pi = SSA_NAME_PTR_INFO (ptr); + var = referenced_var (i); - if (!TREE_VISITED (ptr) - || !POINTER_TYPE_P (TREE_TYPE (ptr)) - || !pi - || !pi->name_mem_tag - || TREE_VISITED (pi->name_mem_tag)) - continue; + if (memory_partition (var)) + var = memory_partition (var); - TREE_VISITED (pi->name_mem_tag) = 1; + if (!MTAG_P (var) && !var_ann (var)->call_clobbered) + { + error ("variable in call_clobbered_vars but not marked " + "call_clobbered"); + debug_variable (var); + goto err; + } + } - if (pi->pt_vars == NULL) + FOR_EACH_REFERENCED_VAR (var, rvi) + { + if (is_gimple_reg (var)) continue; - VEC_safe_push (tree, name_tag_reps, ptr); - VEC_safe_push (bitmap, pt_vars_for_reps, pi->pt_vars); + if (memory_partition (var)) + var = memory_partition (var); - /* Verify that alias set of PTR's type tag is a superset of the - alias set of PTR's name tag. */ - tmt = var_ann (SSA_NAME_VAR (ptr))->type_mem_tag; - if (tmt) + if (!MTAG_P (var) + && var_ann (var)->call_clobbered + && !bitmap_bit_p (gimple_call_clobbered_vars (cfun), DECL_UID (var))) { - size_t i; - varray_type aliases = var_ann (tmt)->may_aliases; - bitmap_clear (type_aliases); - for (i = 0; aliases && i < VARRAY_ACTIVE_SIZE (aliases); i++) - { - tree alias = VARRAY_TREE (aliases, i); - bitmap_set_bit (type_aliases, var_ann (alias)->uid); - } + error ("variable marked call_clobbered but not in " + "call_clobbered_vars bitmap."); + debug_variable (var); + goto err; + } + } + + return; + + err: + internal_error ("verify_call_clobbering failed"); +} + + +/* Verify invariants in memory partitions. */ + +static void +verify_memory_partitions (void) +{ + unsigned i; + tree mpt; + VEC(tree,heap) *mpt_table = gimple_ssa_operands (cfun)->mpt_table; + struct pointer_set_t *partitioned_syms = pointer_set_create (); - /* When grouping, we may have added PTR's type tag into the - alias set of PTR's name tag. To prevent a false - positive, pretend that TMT is in its own alias set. */ - bitmap_set_bit (type_aliases, var_ann (tmt)->uid); + for (i = 0; VEC_iterate (tree, mpt_table, i, mpt); i++) + { + unsigned j; + bitmap_iterator bj; - if (bitmap_equal_p (type_aliases, pi->pt_vars)) - continue; + if (MPT_SYMBOLS (mpt) == NULL) + { + error ("Memory partitions should have at least one symbol"); + debug_variable (mpt); + goto err; + } - if (!bitmap_intersect_compl_p (type_aliases, pi->pt_vars)) + EXECUTE_IF_SET_IN_BITMAP (MPT_SYMBOLS (mpt), 0, j, bj) + { + tree var = referenced_var (j); + if (pointer_set_insert (partitioned_syms, var)) { - error ("Alias set of a pointer's type tag should be a superset of the corresponding name tag"); - debug_variable (tmt); - debug_variable (pi->name_mem_tag); + error ("Partitioned symbols should belong to exactly one " + "partition"); + debug_variable (var); goto err; } } } - - /* Now compare all the representative bitmaps with all other representative - bitmaps, to verify that they are all different. */ - for (i = 0; VEC_iterate (bitmap, pt_vars_for_reps, i, first); i++) - { - for (j = i + 1; VEC_iterate (bitmap, pt_vars_for_reps, j, second); j++) - { - if (bitmap_equal_p (first, second)) - { - error ("Two different pointers with identical points-to sets but different name tags"); - debug_variable (VEC_index (tree, name_tag_reps, j)); - goto err; - } - } - } - /* Lastly, clear out the visited flags. */ - for (i = 0; i < num_ssa_names; i++) - { - if (ssa_name (i)) - { - tree ptr = ssa_name (i); - struct ptr_info_def *pi = SSA_NAME_PTR_INFO (ptr); - if (!TREE_VISITED (ptr) - || !POINTER_TYPE_P (TREE_TYPE (ptr)) - || !pi - || !pi->name_mem_tag) - continue; - TREE_VISITED (pi->name_mem_tag) = 0; - } - } + pointer_set_destroy (partitioned_syms); - VEC_free (bitmap, pt_vars_for_reps); - BITMAP_FREE (type_aliases); return; - + err: - debug_variable (VEC_index (tree, name_tag_reps, i)); - internal_error ("verify_name_tags failed"); + internal_error ("verify_memory_partitions failed"); } @@ -587,8 +707,9 @@ static void verify_alias_info (void) { verify_flow_sensitive_alias_info (); - verify_name_tags (); + verify_call_clobbering (); verify_flow_insensitive_alias_info (); + verify_memory_partitions (); } @@ -596,16 +717,20 @@ verify_alias_info (void) TODO: verify the variable annotations. */ void -verify_ssa (void) +verify_ssa (bool check_modified_stmt) { size_t i; basic_block bb; - basic_block *definition_block = xcalloc (num_ssa_names, sizeof (basic_block)); + basic_block *definition_block = XCNEWVEC (basic_block, num_ssa_names); ssa_op_iter iter; tree op; - enum dom_state orig_dom_state = dom_computed[CDI_DOMINATORS]; + enum dom_state orig_dom_state = dom_info_state (CDI_DOMINATORS); bitmap names_defined_in_bb = BITMAP_ALLOC (NULL); + gcc_assert (!need_ssa_update_p ()); + + verify_stmts (); + timevar_push (TV_TREE_SSA_VERIFY); /* Keep track of SSA names present in the IL. */ @@ -644,7 +769,7 @@ verify_ssa (void) { if (e->aux) { - error ("AUX pointer initialized for edge %d->%d\n", e->src->index, + error ("AUX pointer initialized for edge %d->%d", e->src->index, e->dest->index); goto err; } @@ -655,6 +780,7 @@ verify_ssa (void) { if (verify_phi_args (phi, bb, definition_block)) goto err; + bitmap_set_bit (names_defined_in_bb, SSA_NAME_VERSION (PHI_RESULT (phi))); } @@ -663,51 +789,162 @@ verify_ssa (void) for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi)) { tree stmt = bsi_stmt (bsi); + use_operand_p use_p; - get_stmt_operands (stmt); + if (check_modified_stmt && stmt_modified_p (stmt)) + { + error ("stmt (%p) marked modified after optimization pass: ", + (void *)stmt); + print_generic_stmt (stderr, stmt, TDF_VOPS); + goto err; + } - if (stmt_ann (stmt)->makes_aliased_stores - && NUM_V_MAY_DEFS (STMT_V_MAY_DEF_OPS (stmt)) == 0) + if (TREE_CODE (stmt) == GIMPLE_MODIFY_STMT + && TREE_CODE (GIMPLE_STMT_OPERAND (stmt, 0)) != SSA_NAME) + { + tree lhs, base_address; + + lhs = GIMPLE_STMT_OPERAND (stmt, 0); + base_address = get_base_address (lhs); + + if (base_address + && gimple_aliases_computed_p (cfun) + && SSA_VAR_P (base_address) + && !stmt_ann (stmt)->has_volatile_ops + && ZERO_SSA_OPERANDS (stmt, SSA_OP_VDEF)) { - error ("Statement makes aliased stores, but has no V_MAY_DEFS"); + error ("statement makes a memory store, but has no VDEFS"); print_generic_stmt (stderr, stmt, TDF_VOPS); goto err; } + } + + FOR_EACH_SSA_TREE_OPERAND (op, stmt, iter, SSA_OP_ALL_VIRTUALS) + { + if (verify_ssa_name (op, true)) + { + error ("in statement"); + print_generic_stmt (stderr, stmt, TDF_VOPS|TDF_MEMSYMS); + goto err; + } + } + + FOR_EACH_SSA_TREE_OPERAND (op, stmt, iter, SSA_OP_USE|SSA_OP_DEF) + { + if (verify_ssa_name (op, false)) + { + error ("in statement"); + print_generic_stmt (stderr, stmt, TDF_VOPS|TDF_MEMSYMS); + goto err; + } + } - FOR_EACH_SSA_TREE_OPERAND (op, stmt, iter, SSA_OP_ALL_USES | SSA_OP_ALL_KILLS) + FOR_EACH_SSA_USE_OPERAND (use_p, stmt, iter, SSA_OP_USE|SSA_OP_VUSE) { + op = USE_FROM_PTR (use_p); if (verify_use (bb, definition_block[SSA_NAME_VERSION (op)], - op, stmt, false, !is_gimple_reg (op), - names_defined_in_bb)) + use_p, stmt, false, names_defined_in_bb)) goto err; } FOR_EACH_SSA_TREE_OPERAND (op, stmt, iter, SSA_OP_ALL_DEFS) - { - bitmap_set_bit (names_defined_in_bb, SSA_NAME_VERSION (op)); - } + bitmap_set_bit (names_defined_in_bb, SSA_NAME_VERSION (op)); } bitmap_clear (names_defined_in_bb); } /* Finally, verify alias information. */ - verify_alias_info (); + if (gimple_aliases_computed_p (cfun)) + verify_alias_info (); free (definition_block); + /* Restore the dominance information to its prior known state, so that we do not perturb the compiler's subsequent behavior. */ if (orig_dom_state == DOM_NONE) free_dominance_info (CDI_DOMINATORS); else - dom_computed[CDI_DOMINATORS] = orig_dom_state; + set_dom_info_availability (CDI_DOMINATORS, orig_dom_state); BITMAP_FREE (names_defined_in_bb); timevar_pop (TV_TREE_SSA_VERIFY); return; err: - internal_error ("verify_ssa failed."); + internal_error ("verify_ssa failed"); +} + +/* Return true if the uid in both int tree maps are equal. */ + +int +int_tree_map_eq (const void *va, const void *vb) +{ + const struct int_tree_map *a = (const struct int_tree_map *) va; + const struct int_tree_map *b = (const struct int_tree_map *) vb; + return (a->uid == b->uid); +} + +/* Hash a UID in a int_tree_map. */ + +unsigned int +int_tree_map_hash (const void *item) +{ + return ((const struct int_tree_map *)item)->uid; +} + +/* Return true if the DECL_UID in both trees are equal. */ + +int +uid_decl_map_eq (const void *va, const void *vb) +{ + const_tree a = (const_tree) va; + const_tree b = (const_tree) vb; + return (a->decl_minimal.uid == b->decl_minimal.uid); +} + +/* Hash a tree in a uid_decl_map. */ + +unsigned int +uid_decl_map_hash (const void *item) +{ + return ((const_tree)item)->decl_minimal.uid; +} + +/* Return true if the uid in both int tree maps are equal. */ + +static int +var_ann_eq (const void *va, const void *vb) +{ + const struct static_var_ann_d *a = (const struct static_var_ann_d *) va; + const_tree const b = (const_tree) vb; + return (a->uid == DECL_UID (b)); +} + +/* Hash a UID in a int_tree_map. */ + +static unsigned int +var_ann_hash (const void *item) +{ + return ((const struct static_var_ann_d *)item)->uid; +} + +/* Return true if the DECL_UID in both trees are equal. */ + +static int +uid_ssaname_map_eq (const void *va, const void *vb) +{ + const_tree a = (const_tree) va; + const_tree b = (const_tree) vb; + return (a->ssa_name.var->decl_minimal.uid == b->ssa_name.var->decl_minimal.uid); +} + +/* Hash a tree in a uid_decl_map. */ + +static unsigned int +uid_ssaname_map_hash (const void *item) +{ + return ((const_tree)item)->ssa_name.var->decl_minimal.uid; } @@ -716,14 +953,17 @@ err: void init_tree_ssa (void) { - VARRAY_TREE_INIT (referenced_vars, 20, "referenced_vars"); - call_clobbered_vars = BITMAP_ALLOC (NULL); - addressable_vars = BITMAP_ALLOC (NULL); - init_ssa_operands (); + cfun->gimple_df = GGC_CNEW (struct gimple_df); + cfun->gimple_df->referenced_vars = htab_create_ggc (20, uid_decl_map_hash, + uid_decl_map_eq, NULL); + cfun->gimple_df->default_defs = htab_create_ggc (20, uid_ssaname_map_hash, + uid_ssaname_map_eq, NULL); + cfun->gimple_df->var_anns = htab_create_ggc (20, var_ann_hash, + var_ann_eq, NULL); + cfun->gimple_df->call_clobbered_vars = BITMAP_GGC_ALLOC (); + cfun->gimple_df->addressable_vars = BITMAP_GGC_ALLOC (); init_ssanames (); init_phinodes (); - global_var = NULL_TREE; - aliases_computed_p = false; } @@ -735,113 +975,244 @@ delete_tree_ssa (void) size_t i; basic_block bb; block_stmt_iterator bsi; + referenced_var_iterator rvi; + tree var; + + /* Release any ssa_names still in use. */ + for (i = 0; i < num_ssa_names; i++) + { + tree var = ssa_name (i); + if (var && TREE_CODE (var) == SSA_NAME) + { + SSA_NAME_IMM_USE_NODE (var).prev = &(SSA_NAME_IMM_USE_NODE (var)); + SSA_NAME_IMM_USE_NODE (var).next = &(SSA_NAME_IMM_USE_NODE (var)); + } + release_ssa_name (var); + } /* Remove annotations from every tree in the function. */ FOR_EACH_BB (bb) - for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi)) - { - tree stmt = bsi_stmt (bsi); - release_defs (stmt); - ggc_free (stmt->common.ann); - stmt->common.ann = NULL; - } - - /* Remove annotations from every referenced variable. */ - if (referenced_vars) { - for (i = 0; i < num_referenced_vars; i++) + for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi)) { - tree var = referenced_var (i); - ggc_free (var->common.ann); - var->common.ann = NULL; + tree stmt = bsi_stmt (bsi); + stmt_ann_t ann = get_stmt_ann (stmt); + + free_ssa_operands (&ann->operands); + ann->addresses_taken = 0; + mark_stmt_modified (stmt); } - referenced_vars = NULL; + set_phi_nodes (bb, NULL); + } + + /* Remove annotations from every referenced variable. */ + FOR_EACH_REFERENCED_VAR (var, rvi) + { + if (var->base.ann) + ggc_free (var->base.ann); + var->base.ann = NULL; } + htab_delete (gimple_referenced_vars (cfun)); + cfun->gimple_df->referenced_vars = NULL; fini_ssanames (); fini_phinodes (); - fini_ssa_operands (); - - global_var = NULL_TREE; - BITMAP_FREE (call_clobbered_vars); - call_clobbered_vars = NULL; - BITMAP_FREE (addressable_vars); - addressable_vars = NULL; - modified_noreturn_calls = NULL; - aliases_computed_p = false; -} + /* we no longer maintain the SSA operand cache at this point. */ + if (ssa_operands_active ()) + fini_ssa_operands (); + cfun->gimple_df->global_var = NULL_TREE; + + htab_delete (cfun->gimple_df->default_defs); + cfun->gimple_df->default_defs = NULL; + htab_delete (cfun->gimple_df->var_anns); + cfun->gimple_df->var_anns = NULL; + cfun->gimple_df->call_clobbered_vars = NULL; + cfun->gimple_df->addressable_vars = NULL; + cfun->gimple_df->modified_noreturn_calls = NULL; + if (gimple_aliases_computed_p (cfun)) + { + delete_alias_heapvars (); + gcc_assert (!need_ssa_update_p ()); + } + cfun->gimple_df->aliases_computed_p = false; + delete_mem_ref_stats (cfun); -/* Return true if EXPR is a useless type conversion, otherwise return - false. */ + cfun->gimple_df = NULL; -bool -tree_ssa_useless_type_conversion_1 (tree outer_type, tree inner_type) + /* We no longer need the edge variable maps. */ + redirect_edge_var_map_destroy (); +} + +/* Helper function for useless_type_conversion_p. */ + +static bool +useless_type_conversion_p_1 (tree outer_type, tree inner_type) { + /* Qualifiers on value types do not matter. */ + inner_type = TYPE_MAIN_VARIANT (inner_type); + outer_type = TYPE_MAIN_VARIANT (outer_type); + if (inner_type == outer_type) return true; + /* If we know the canonical types, compare them. */ + if (TYPE_CANONICAL (inner_type) + && TYPE_CANONICAL (inner_type) == TYPE_CANONICAL (outer_type)) + return true; + /* Changes in machine mode are never useless conversions. */ if (TYPE_MODE (inner_type) != TYPE_MODE (outer_type)) return false; - /* If the inner and outer types are effectively the same, then - strip the type conversion and enter the equivalence into - the table. */ - if (lang_hooks.types_compatible_p (inner_type, outer_type)) - return true; + /* If both the inner and outer types are integral types, then the + conversion is not necessary if they have the same mode and + signedness and precision, and both or neither are boolean. */ + if (INTEGRAL_TYPE_P (inner_type) + && INTEGRAL_TYPE_P (outer_type)) + { + /* Preserve changes in signedness or precision. */ + if (TYPE_UNSIGNED (inner_type) != TYPE_UNSIGNED (outer_type) + || TYPE_PRECISION (inner_type) != TYPE_PRECISION (outer_type)) + return false; + + /* Conversions from a non-base to a base type are not useless. + This way we preserve the invariant to do arithmetic in + base types only. */ + if (TREE_TYPE (inner_type) + && TREE_TYPE (inner_type) != inner_type + && (TREE_TYPE (outer_type) == outer_type + || TREE_TYPE (outer_type) == NULL_TREE)) + return false; + + /* We don't need to preserve changes in the types minimum or + maximum value in general as these do not generate code + unless the types precisions are different. */ - /* If both types are pointers and the outer type is a (void *), then - the conversion is not necessary. The opposite is not true since - that conversion would result in a loss of information if the - equivalence was used. Consider an indirect function call where - we need to know the exact type of the function to correctly - implement the ABI. */ - else if (POINTER_TYPE_P (inner_type) - && POINTER_TYPE_P (outer_type) - && TYPE_REF_CAN_ALIAS_ALL (inner_type) - == TYPE_REF_CAN_ALIAS_ALL (outer_type) - && TREE_CODE (TREE_TYPE (outer_type)) == VOID_TYPE) - return true; + return true; + } - /* Pointers and references are equivalent once we get to GENERIC, - so strip conversions that just switch between them. */ - else if (POINTER_TYPE_P (inner_type) - && POINTER_TYPE_P (outer_type) - && TYPE_REF_CAN_ALIAS_ALL (inner_type) - == TYPE_REF_CAN_ALIAS_ALL (outer_type) - && lang_hooks.types_compatible_p (TREE_TYPE (inner_type), - TREE_TYPE (outer_type))) + /* Scalar floating point types with the same mode are compatible. */ + else if (SCALAR_FLOAT_TYPE_P (inner_type) + && SCALAR_FLOAT_TYPE_P (outer_type)) return true; - /* If both the inner and outer types are integral types, then the - conversion is not necessary if they have the same mode and - signedness and precision, and both or neither are boolean. Some - code assumes an invariant that boolean types stay boolean and do - not become 1-bit bit-field types. Note that types with precision - not using all bits of the mode (such as bit-field types in C) - mean that testing of precision is necessary. */ - else if (INTEGRAL_TYPE_P (inner_type) - && INTEGRAL_TYPE_P (outer_type) - && TYPE_UNSIGNED (inner_type) == TYPE_UNSIGNED (outer_type) - && TYPE_PRECISION (inner_type) == TYPE_PRECISION (outer_type)) + /* We need to take special care recursing to pointed-to types. */ + else if (POINTER_TYPE_P (inner_type) + && POINTER_TYPE_P (outer_type)) { - bool first_boolean = (TREE_CODE (inner_type) == BOOLEAN_TYPE); - bool second_boolean = (TREE_CODE (outer_type) == BOOLEAN_TYPE); - if (first_boolean == second_boolean) - return true; + /* Don't lose casts between pointers to volatile and non-volatile + qualified types. Doing so would result in changing the semantics + of later accesses. */ + if ((TYPE_VOLATILE (TREE_TYPE (outer_type)) + != TYPE_VOLATILE (TREE_TYPE (inner_type))) + && TYPE_VOLATILE (TREE_TYPE (outer_type))) + return false; + + /* Do not lose casts between pointers with different + TYPE_REF_CAN_ALIAS_ALL setting or alias sets. */ + if ((TYPE_REF_CAN_ALIAS_ALL (inner_type) + != TYPE_REF_CAN_ALIAS_ALL (outer_type)) + || (get_alias_set (TREE_TYPE (inner_type)) + != get_alias_set (TREE_TYPE (outer_type)))) + return false; + + /* We do not care for const qualification of the pointed-to types + as const qualification has no semantic value to the middle-end. */ + + /* Do not lose casts to restrict qualified pointers. */ + if ((TYPE_RESTRICT (outer_type) + != TYPE_RESTRICT (inner_type)) + && TYPE_RESTRICT (outer_type)) + return false; + + /* Otherwise pointers/references are equivalent if their pointed + to types are effectively the same. We can strip qualifiers + on pointed-to types for further comparison, which is done in + the callee. */ + return useless_type_conversion_p_1 (TREE_TYPE (outer_type), + TREE_TYPE (inner_type)); } /* Recurse for complex types. */ else if (TREE_CODE (inner_type) == COMPLEX_TYPE - && TREE_CODE (outer_type) == COMPLEX_TYPE - && tree_ssa_useless_type_conversion_1 (TREE_TYPE (outer_type), - TREE_TYPE (inner_type))) - return true; + && TREE_CODE (outer_type) == COMPLEX_TYPE) + return useless_type_conversion_p_1 (TREE_TYPE (outer_type), + TREE_TYPE (inner_type)); + + /* Recurse for vector types with the same number of subparts. */ + else if (TREE_CODE (inner_type) == VECTOR_TYPE + && TREE_CODE (outer_type) == VECTOR_TYPE + && TYPE_PRECISION (inner_type) == TYPE_PRECISION (outer_type)) + return useless_type_conversion_p_1 (TREE_TYPE (outer_type), + TREE_TYPE (inner_type)); + + /* For aggregates we may need to fall back to structural equality + checks. */ + else if (AGGREGATE_TYPE_P (inner_type) + && AGGREGATE_TYPE_P (outer_type)) + { + /* Different types of aggregates are incompatible. */ + if (TREE_CODE (inner_type) != TREE_CODE (outer_type)) + return false; + + /* ??? Add structural equivalence check. */ + + /* ??? This should eventually just return false. */ + return lang_hooks.types_compatible_p (inner_type, outer_type); + } return false; } +/* Return true if the conversion from INNER_TYPE to OUTER_TYPE is a + useless type conversion, otherwise return false. + + This function implicitly defines the middle-end type system. With + the notion of 'a < b' meaning that useless_type_conversion_p (a, b) + holds and 'a > b' meaning that useless_type_conversion_p (b, a) holds, + the following invariants shall be fulfilled: + + 1) useless_type_conversion_p is transitive. + If a < b and b < c then a < c. + + 2) useless_type_conversion_p is not symmetric. + From a < b does not follow a > b. + + 3) Types define the available set of operations applicable to values. + A type conversion is useless if the operations for the target type + is a subset of the operations for the source type. For example + casts to void* are useless, casts from void* are not (void* can't + be dereferenced or offsetted, but copied, hence its set of operations + is a strict subset of that of all other data pointer types). Casts + to const T* are useless (can't be written to), casts from const T* + to T* are not. */ + +bool +useless_type_conversion_p (tree outer_type, tree inner_type) +{ + /* If the outer type is (void *), then the conversion is not + necessary. We have to make sure to not apply this while + recursing though. */ + if (POINTER_TYPE_P (inner_type) + && POINTER_TYPE_P (outer_type) + && TREE_CODE (TREE_TYPE (outer_type)) == VOID_TYPE) + return true; + + return useless_type_conversion_p_1 (outer_type, inner_type); +} + +/* Return true if a conversion from either type of TYPE1 and TYPE2 + to the other is not required. Otherwise return false. */ + +bool +types_compatible_p (tree type1, tree type2) +{ + return (type1 == type2 + || (useless_type_conversion_p (type1, type2) + && useless_type_conversion_p (type2, type1))); +} + /* Return true if EXPR is a useless type conversion, otherwise return false. */ @@ -855,31 +1226,16 @@ tree_ssa_useless_type_conversion (tree expr) if (TREE_CODE (expr) == NOP_EXPR || TREE_CODE (expr) == CONVERT_EXPR || TREE_CODE (expr) == VIEW_CONVERT_EXPR || TREE_CODE (expr) == NON_LVALUE_EXPR) - return tree_ssa_useless_type_conversion_1 (TREE_TYPE (expr), - TREE_TYPE (TREE_OPERAND (expr, - 0))); - + /* FIXME: Use of GENERIC_TREE_TYPE here is a temporary measure to work + around known bugs with GIMPLE_MODIFY_STMTs appearing in places + they shouldn't. See PR 30391. */ + return useless_type_conversion_p + (TREE_TYPE (expr), + GENERIC_TREE_TYPE (TREE_OPERAND (expr, 0))); return false; } -/* Returns true if statement STMT may read memory. */ - -bool -stmt_references_memory_p (tree stmt) -{ - stmt_ann_t ann; - - get_stmt_operands (stmt); - ann = stmt_ann (stmt); - - if (ann->has_volatile_ops) - return true; - - return (NUM_VUSES (VUSE_OPS (ann)) > 0 - || NUM_V_MAY_DEFS (V_MAY_DEF_OPS (ann)) > 0 - || NUM_V_MUST_DEFS (V_MUST_DEF_OPS (ann)) > 0); -} /* Internal helper for walk_use_def_chains. VAR, FN and DATA are as described in walk_use_def_chains. @@ -926,7 +1282,10 @@ walk_use_def_chains_1 (tree var, walk_use_def_chains_fn fn, void *data, for (i = 0; i < PHI_NUM_ARGS (def_stmt); i++) { tree arg = PHI_ARG_DEF (def_stmt, i); - if (TREE_CODE (arg) == SSA_NAME + + /* ARG may be NULL for newly introduced PHI nodes. */ + if (arg + && TREE_CODE (arg) == SSA_NAME && walk_use_def_chains_1 (arg, fn, data, visited, is_dfs)) return true; } @@ -964,7 +1323,6 @@ walk_use_def_chains_1 (tree var, walk_use_def_chains_fn fn, void *data, If IS_DFS is false, the two steps above are done in reverse order (i.e., a breadth-first search). */ - void walk_use_def_chains (tree var, walk_use_def_chains_fn fn, void *data, bool is_dfs) @@ -987,338 +1345,29 @@ walk_use_def_chains (tree var, walk_use_def_chains_fn fn, void *data, } } + +/* Return true if T, an SSA_NAME, has an undefined value. */ -/* Replaces VAR with REPL in memory reference expression *X in - statement STMT. */ - -static void -propagate_into_addr (tree stmt, tree var, tree *x, tree repl) -{ - tree new_var, ass_stmt, addr_var; - basic_block bb; - block_stmt_iterator bsi; - - /* There is nothing special to handle in the other cases. */ - if (TREE_CODE (repl) != ADDR_EXPR) - return; - addr_var = TREE_OPERAND (repl, 0); - - while (handled_component_p (*x) - || TREE_CODE (*x) == REALPART_EXPR - || TREE_CODE (*x) == IMAGPART_EXPR) - x = &TREE_OPERAND (*x, 0); - - if (TREE_CODE (*x) != INDIRECT_REF - || TREE_OPERAND (*x, 0) != var) - return; - - if (TREE_TYPE (*x) == TREE_TYPE (addr_var)) - { - *x = addr_var; - mark_new_vars_to_rename (stmt, vars_to_rename); - return; - } - - - /* Frontends sometimes produce expressions like *&a instead of a[0]. - Create a temporary variable to handle this case. */ - ass_stmt = build2 (MODIFY_EXPR, void_type_node, NULL_TREE, repl); - new_var = duplicate_ssa_name (var, ass_stmt); - TREE_OPERAND (*x, 0) = new_var; - TREE_OPERAND (ass_stmt, 0) = new_var; - - bb = bb_for_stmt (stmt); - tree_block_label (bb); - bsi = bsi_after_labels (bb); - bsi_insert_after (&bsi, ass_stmt, BSI_NEW_STMT); - - mark_new_vars_to_rename (stmt, vars_to_rename); -} - -/* Replaces immediate uses of VAR by REPL. */ - -static void -replace_immediate_uses (tree var, tree repl) -{ - int i, j, n; - dataflow_t df; - tree stmt; - bool mark_new_vars; - ssa_op_iter iter; - use_operand_p use_p; - - df = get_immediate_uses (SSA_NAME_DEF_STMT (var)); - n = num_immediate_uses (df); - - for (i = 0; i < n; i++) - { - stmt = immediate_use (df, i); - - if (TREE_CODE (stmt) == PHI_NODE) - { - for (j = 0; j < PHI_NUM_ARGS (stmt); j++) - if (PHI_ARG_DEF (stmt, j) == var) - { - SET_PHI_ARG_DEF (stmt, j, repl); - if (TREE_CODE (repl) == SSA_NAME - && PHI_ARG_EDGE (stmt, j)->flags & EDGE_ABNORMAL) - SSA_NAME_OCCURS_IN_ABNORMAL_PHI (repl) = 1; - } - - continue; - } - - get_stmt_operands (stmt); - mark_new_vars = false; - if (is_gimple_reg (SSA_NAME_VAR (var))) - { - if (TREE_CODE (stmt) == MODIFY_EXPR) - { - propagate_into_addr (stmt, var, &TREE_OPERAND (stmt, 0), repl); - propagate_into_addr (stmt, var, &TREE_OPERAND (stmt, 1), repl); - } - - FOR_EACH_SSA_USE_OPERAND (use_p, stmt, iter, SSA_OP_USE) - if (USE_FROM_PTR (use_p) == var) - { - propagate_value (use_p, repl); - mark_new_vars = POINTER_TYPE_P (TREE_TYPE (repl)); - } - } - else - { - FOR_EACH_SSA_USE_OPERAND (use_p, stmt, iter, - SSA_OP_VIRTUAL_USES | SSA_OP_VIRTUAL_KILLS) - if (USE_FROM_PTR (use_p) == var) - propagate_value (use_p, repl); - } - - /* FIXME. If REPL is a constant, we need to fold STMT. - However, fold_stmt wants a pointer to the statement, because - it may happen that it needs to replace the whole statement - with a new expression. Since the current def-use machinery - does not return pointers to statements, we call fold_stmt - with the address of a local temporary, if that call changes - the temporary then we fallback on looking for a proper - pointer to STMT by scanning STMT's basic block. - - Note that all this will become unnecessary soon. This - pass is being replaced with a proper copy propagation pass - for 4.1 (dnovillo, 2004-09-17). */ - if (TREE_CODE (repl) != SSA_NAME) - { - tree tmp = stmt; - fold_stmt (&tmp); - mark_new_vars = true; - if (tmp != stmt) - { - block_stmt_iterator si = bsi_for_stmt (stmt); - mark_new_vars_to_rename (tmp, vars_to_rename); - redirect_immediate_uses (stmt, tmp); - bsi_replace (&si, tmp, true); - stmt = bsi_stmt (si); - } - } - - /* If REPL is a pointer, it may have different memory tags associated - with it. For instance, VAR may have had a name tag while REPL - only had a type tag. In these cases, the virtual operands (if - any) in the statement will refer to different symbols which need - to be renamed. */ - if (mark_new_vars) - mark_new_vars_to_rename (stmt, vars_to_rename); - else - modify_stmt (stmt); - } -} - -/* Gets the value VAR is equivalent to according to EQ_TO. */ - -static tree -get_eq_name (tree *eq_to, tree var) -{ - unsigned ver; - tree val = var; - - while (TREE_CODE (val) == SSA_NAME) - { - ver = SSA_NAME_VERSION (val); - if (!eq_to[ver]) - break; - - val = eq_to[ver]; - } - - while (TREE_CODE (var) == SSA_NAME) - { - ver = SSA_NAME_VERSION (var); - if (!eq_to[ver]) - break; - - var = eq_to[ver]; - eq_to[ver] = val; - } - - return val; -} - -/* Checks whether phi node PHI is redundant and if it is, records the ssa name - its result is redundant to to EQ_TO array. */ - -static void -check_phi_redundancy (tree phi, tree *eq_to) -{ - tree val = NULL_TREE, def, res = PHI_RESULT (phi), stmt; - unsigned i, ver = SSA_NAME_VERSION (res), n; - dataflow_t df; - - /* It is unlikely that such large phi node would be redundant. */ - if (PHI_NUM_ARGS (phi) > 16) - return; - - for (i = 0; i < (unsigned) PHI_NUM_ARGS (phi); i++) - { - def = PHI_ARG_DEF (phi, i); - - if (TREE_CODE (def) == SSA_NAME) - { - def = get_eq_name (eq_to, def); - if (def == res) - continue; - } - - if (val - && !operand_equal_for_phi_arg_p (val, def)) - return; - - val = def; - } - - /* At least one of the arguments should not be equal to the result, or - something strange is happening. */ - gcc_assert (val); - - if (get_eq_name (eq_to, res) == val) - return; - - if (!may_propagate_copy (res, val)) - return; - - eq_to[ver] = val; - - df = get_immediate_uses (SSA_NAME_DEF_STMT (res)); - n = num_immediate_uses (df); - - for (i = 0; i < n; i++) - { - stmt = immediate_use (df, i); - - if (TREE_CODE (stmt) == PHI_NODE) - check_phi_redundancy (stmt, eq_to); - } -} - -/* Removes redundant phi nodes. - - A redundant PHI node is a PHI node where all of its PHI arguments - are the same value, excluding any PHI arguments which are the same - as the PHI result. - - A redundant PHI node is effectively a copy, so we forward copy propagate - which removes all uses of the destination of the PHI node then - finally we delete the redundant PHI node. - - Note that if we can not copy propagate the PHI node, then the PHI - will not be removed. Thus we do not have to worry about dependencies - between PHIs and the problems serializing PHIs into copies creates. - - The most important effect of this pass is to remove degenerate PHI - nodes created by removing unreachable code. */ - -void -kill_redundant_phi_nodes (void) +bool +ssa_undefined_value_p (tree t) { - tree *eq_to; - unsigned i, old_num_ssa_names; - basic_block bb; - tree phi, var, repl, stmt; - - /* The EQ_TO[VER] holds the value by that the ssa name VER should be - replaced. If EQ_TO[VER] is ssa name and it is decided to replace it by - other value, it may be necessary to follow the chain till the final value. - We perform path shortening (replacing the entries of the EQ_TO array with - heads of these chains) whenever we access the field to prevent quadratic - complexity (probably would not occur in practice anyway, but let us play - it safe). */ - eq_to = xcalloc (num_ssa_names, sizeof (tree)); - - /* We have had cases where computing immediate uses takes a - significant amount of compile time. If we run into such - problems here, we may want to only compute immediate uses for - a subset of all the SSA_NAMEs instead of computing it for - all of the SSA_NAMEs. */ - compute_immediate_uses (TDFA_USE_OPS | TDFA_USE_VOPS, NULL); - old_num_ssa_names = num_ssa_names; - - FOR_EACH_BB (bb) - { - for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi)) - { - var = PHI_RESULT (phi); - check_phi_redundancy (phi, eq_to); - } - } - - /* Now propagate the values. */ - for (i = 0; i < old_num_ssa_names; i++) - { - if (!ssa_name (i)) - continue; - - repl = get_eq_name (eq_to, ssa_name (i)); - if (repl != ssa_name (i)) - replace_immediate_uses (ssa_name (i), repl); - } + tree var = SSA_NAME_VAR (t); - /* And remove the dead phis. */ - for (i = 0; i < old_num_ssa_names; i++) - { - if (!ssa_name (i)) - continue; + /* Parameters get their initial value from the function entry. */ + if (TREE_CODE (var) == PARM_DECL) + return false; - repl = get_eq_name (eq_to, ssa_name (i)); - if (repl != ssa_name (i)) - { - stmt = SSA_NAME_DEF_STMT (ssa_name (i)); - remove_phi_node (stmt, NULL_TREE, bb_for_stmt (stmt)); - } - } + /* Hard register variables get their initial value from the ether. */ + if (TREE_CODE (var) == VAR_DECL && DECL_HARD_REGISTER (var)) + return false; - free_df (); - free (eq_to); + /* The value is undefined iff its definition statement is empty. */ + return IS_EMPTY_STMT (SSA_NAME_DEF_STMT (t)); } -struct tree_opt_pass pass_redundant_phi = -{ - "redphi", /* name */ - NULL, /* gate */ - kill_redundant_phi_nodes, /* execute */ - NULL, /* sub */ - NULL, /* next */ - 0, /* static_pass_number */ - TV_TREE_REDPHI, /* tv_id */ - PROP_cfg | PROP_ssa | PROP_alias, /* properties_required */ - 0, /* properties_provided */ - 0, /* properties_destroyed */ - 0, /* todo_flags_start */ - TODO_dump_func | TODO_rename_vars - | TODO_ggc_collect | TODO_verify_ssa, /* todo_flags_finish */ - 0 /* letter */ -}; - /* Emit warnings for uninitialized variables. This is done in two passes. - The first pass notices real uses of SSA names with default definitions. + The first pass notices real uses of SSA names with undefined values. Such uses are unconditionally uninitialized, and we can be certain that such a use is a mistake. This pass is run before most optimizations, so that we catch as many as we can. @@ -1335,22 +1384,14 @@ struct tree_opt_pass pass_redundant_phi = warning text is in MSGID and LOCUS may contain a location or be null. */ static void -warn_uninit (tree t, const char *msgid, location_t *locus) +warn_uninit (tree t, const char *gmsgid, void *data) { tree var = SSA_NAME_VAR (t); - tree def = SSA_NAME_DEF_STMT (t); - - /* Default uses (indicated by an empty definition statement), - are uninitialized. */ - if (!IS_EMPTY_STMT (def)) - return; - - /* Except for PARMs of course, which are always initialized. */ - if (TREE_CODE (var) == PARM_DECL) - return; + tree context = (tree) data; + location_t *locus; + expanded_location xloc, floc; - /* Hard register variables get their initial value from the ether. */ - if (TREE_CODE (var) == VAR_DECL && DECL_HARD_REGISTER (var)) + if (!ssa_undefined_value_p (t)) return; /* TREE_NO_WARNING either means we already warned, or the front end @@ -1358,29 +1399,62 @@ warn_uninit (tree t, const char *msgid, location_t *locus) if (TREE_NO_WARNING (var)) return; - if (!locus) - locus = &DECL_SOURCE_LOCATION (var); - warning (msgid, locus, var); + locus = (context != NULL && EXPR_HAS_LOCATION (context) + ? EXPR_LOCUS (context) + : &DECL_SOURCE_LOCATION (var)); + warning (OPT_Wuninitialized, gmsgid, locus, var); + xloc = expand_location (*locus); + floc = expand_location (DECL_SOURCE_LOCATION (cfun->decl)); + if (xloc.file != floc.file + || xloc.line < floc.line + || xloc.line > LOCATION_LINE (cfun->function_end_locus)) + inform ("%J%qD was declared here", var, var); + TREE_NO_WARNING (var) = 1; } - + +struct walk_data { + tree stmt; + bool always_executed; +}; + /* Called via walk_tree, look for SSA_NAMEs that have empty definitions and warn about them. */ static tree -warn_uninitialized_var (tree *tp, int *walk_subtrees, void *data) +warn_uninitialized_var (tree *tp, int *walk_subtrees, void *data_) { - location_t *locus = data; + struct walk_data *data = (struct walk_data *)data_; tree t = *tp; - /* We only do data flow with SSA_NAMEs, so that's all we can warn about. */ - if (TREE_CODE (t) == SSA_NAME) + switch (TREE_CODE (t)) { - warn_uninit (t, "%H%qD is used uninitialized in this function", locus); + case SSA_NAME: + /* We only do data flow with SSA_NAMEs, so that's all we + can warn about. */ + if (data->always_executed) + warn_uninit (t, "%H%qD is used uninitialized in this function", + data->stmt); + else + warn_uninit (t, "%H%qD may be used uninitialized in this function", + data->stmt); *walk_subtrees = 0; + break; + + case REALPART_EXPR: + case IMAGPART_EXPR: + /* The total store transformation performed during gimplification + creates uninitialized variable uses. If all is well, these will + be optimized away, so don't warn now. */ + if (TREE_CODE (TREE_OPERAND (t, 0)) == SSA_NAME) + *walk_subtrees = 0; + break; + + default: + if (IS_TYPE_OR_DECL_P (t)) + *walk_subtrees = 0; + break; } - else if (IS_TYPE_OR_DECL_P (t)) - *walk_subtrees = 0; return NULL_TREE; } @@ -1406,19 +1480,30 @@ warn_uninitialized_phi (tree phi) } } -static void +static unsigned int execute_early_warn_uninitialized (void) { block_stmt_iterator bsi; basic_block bb; + struct walk_data data; + + calculate_dominance_info (CDI_POST_DOMINATORS); FOR_EACH_BB (bb) - for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi)) - walk_tree (bsi_stmt_ptr (bsi), warn_uninitialized_var, - EXPR_LOCUS (bsi_stmt (bsi)), NULL); + { + data.always_executed = dominated_by_p (CDI_POST_DOMINATORS, + single_succ (ENTRY_BLOCK_PTR), bb); + for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi)) + { + data.stmt = bsi_stmt (bsi); + walk_tree (bsi_stmt_ptr (bsi), warn_uninitialized_var, + &data, NULL); + } + } + return 0; } -static void +static unsigned int execute_late_warn_uninitialized (void) { basic_block bb; @@ -1432,6 +1517,7 @@ execute_late_warn_uninitialized (void) FOR_EACH_BB (bb) for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi)) warn_uninitialized_phi (phi); + return 0; } static bool @@ -1440,8 +1526,10 @@ gate_warn_uninitialized (void) return warn_uninitialized != 0; } -struct tree_opt_pass pass_early_warn_uninitialized = +struct gimple_opt_pass pass_early_warn_uninitialized = { + { + GIMPLE_PASS, NULL, /* name */ gate_warn_uninitialized, /* gate */ execute_early_warn_uninitialized, /* execute */ @@ -1453,12 +1541,14 @@ struct tree_opt_pass pass_early_warn_uninitialized = 0, /* properties_provided */ 0, /* properties_destroyed */ 0, /* todo_flags_start */ - 0, /* todo_flags_finish */ - 0 /* letter */ + 0 /* todo_flags_finish */ + } }; -struct tree_opt_pass pass_late_warn_uninitialized = +struct gimple_opt_pass pass_late_warn_uninitialized = { + { + GIMPLE_PASS, NULL, /* name */ gate_warn_uninitialized, /* gate */ execute_late_warn_uninitialized, /* execute */ @@ -1470,7 +1560,104 @@ struct tree_opt_pass pass_late_warn_uninitialized = 0, /* properties_provided */ 0, /* properties_destroyed */ 0, /* todo_flags_start */ - 0, /* todo_flags_finish */ - 0 /* letter */ + 0 /* todo_flags_finish */ + } +}; + +/* Compute TREE_ADDRESSABLE for local variables. */ + +static unsigned int +execute_update_addresses_taken (void) +{ + tree var; + referenced_var_iterator rvi; + block_stmt_iterator bsi; + basic_block bb; + bitmap addresses_taken = BITMAP_ALLOC (NULL); + bitmap vars_updated = BITMAP_ALLOC (NULL); + bool update_vops = false; + tree phi; + + /* Collect into ADDRESSES_TAKEN all variables whose address is taken within + the function body. */ + FOR_EACH_BB (bb) + { + for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi)) + { + stmt_ann_t s_ann = stmt_ann (bsi_stmt (bsi)); + + if (s_ann->addresses_taken) + bitmap_ior_into (addresses_taken, s_ann->addresses_taken); + } + for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi)) + { + unsigned i, phi_num_args = PHI_NUM_ARGS (phi); + for (i = 0; i < phi_num_args; i++) + { + tree op = PHI_ARG_DEF (phi, i), var; + if (TREE_CODE (op) == ADDR_EXPR + && (var = get_base_address (TREE_OPERAND (op, 0))) != NULL_TREE + && DECL_P (var)) + bitmap_set_bit (addresses_taken, DECL_UID (var)); + } + } + } + + /* When possible, clear ADDRESSABLE bit and mark variable for conversion into + SSA. */ + FOR_EACH_REFERENCED_VAR (var, rvi) + if (!is_global_var (var) + && TREE_CODE (var) != RESULT_DECL + && TREE_ADDRESSABLE (var) + && !bitmap_bit_p (addresses_taken, DECL_UID (var))) + { + TREE_ADDRESSABLE (var) = 0; + if (is_gimple_reg (var)) + mark_sym_for_renaming (var); + update_vops = true; + bitmap_set_bit (vars_updated, DECL_UID (var)); + if (dump_file) + { + fprintf (dump_file, "No longer having address taken "); + print_generic_expr (dump_file, var, 0); + fprintf (dump_file, "\n"); + } + } + + /* Operand caches needs to be recomputed for operands referencing the updated + variables. */ + if (update_vops) + FOR_EACH_BB (bb) + for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi)) + { + tree stmt = bsi_stmt (bsi); + + if ((LOADED_SYMS (stmt) + && bitmap_intersect_p (LOADED_SYMS (stmt), vars_updated)) + || (STORED_SYMS (stmt) + && bitmap_intersect_p (STORED_SYMS (stmt), vars_updated))) + update_stmt (stmt); + } + BITMAP_FREE (addresses_taken); + BITMAP_FREE (vars_updated); + return 0; +} + +struct gimple_opt_pass pass_update_address_taken = +{ + { + GIMPLE_PASS, + "addressables", /* name */ + NULL, /* gate */ + execute_update_addresses_taken, /* execute */ + NULL, /* sub */ + NULL, /* next */ + 0, /* static_pass_number */ + 0, /* tv_id */ + PROP_ssa, /* properties_required */ + 0, /* properties_provided */ + 0, /* properties_destroyed */ + 0, /* todo_flags_start */ + TODO_update_ssa /* todo_flags_finish */ + } }; -