X-Git-Url: http://git.sourceforge.jp/view?p=pf3gnuchains%2Fgcc-fork.git;a=blobdiff_plain;f=gcc%2Ftree-ssa.c;h=f922e8254445db516f273e761c644713f1975b66;hp=aa6f5239eb9e607e6d70ccb3c7f70b3ed173a163;hb=b7d1b569577509f4a733da7949c899c936db453b;hpb=2b4876d244c2e5d707b79dc0e63dc930e4705079 diff --git a/gcc/tree-ssa.c b/gcc/tree-ssa.c index aa6f5239eb9..f922e825444 100644 --- a/gcc/tree-ssa.c +++ b/gcc/tree-ssa.c @@ -15,8 +15,8 @@ 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. */ +the Free Software Foundation, 51 Franklin Street, Fifth Floor, +Boston, MA 02110-1301, USA. */ #include "config.h" #include "system.h" @@ -31,7 +31,6 @@ 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" @@ -45,6 +44,7 @@ Boston, MA 02111-1307, USA. */ #include "hashtab.h" #include "tree-dump.h" #include "tree-pass.h" +#include "toplev.h" /* Remove the corresponding arguments from the PHI nodes in E's destination block and redirect it to DEST. Return redirected edge. @@ -53,21 +53,17 @@ Boston, MA 02111-1307, USA. */ edge ssa_redirect_edge (edge e, basic_block dest) { - tree phi, next; + tree phi; tree list = NULL, *last = &list; tree src, dst, node; - int i; /* 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); - - i = phi_arg_from_edge (phi, e); - if (PHI_ARG_DEF (phi, i) == NULL_TREE) + if (PHI_ARG_DEF (phi, e->dest_idx) == NULL_TREE) continue; - src = PHI_ARG_DEF (phi, i); + src = PHI_ARG_DEF (phi, e->dest_idx); dst = PHI_RESULT (phi); node = build_tree_list (dst, src); *last = node; @@ -110,35 +106,40 @@ flush_pending_stmts (edge e) static bool verify_ssa_name (tree ssa_name, bool is_virtual) { - TREE_VISITED (ssa_name) = 1; - 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; } @@ -214,26 +215,33 @@ err: that are defined before STMT in basic block BB. */ static bool -verify_use (basic_block bb, basic_block def_bb, tree ssa_name, +verify_use (basic_block bb, basic_block def_bb, use_operand_p use_p, tree stmt, bool check_abnormal, bool is_virtual, bitmap names_defined_in_bb) { bool err = false; + tree ssa_name = USE_FROM_PTR (use_p); err = verify_ssa_name (ssa_name, is_virtual); + if (!TREE_VISITED (ssa_name)) + if (verify_imm_links (stderr, ssa_name)) + err = true; + + 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) + && default_def (SSA_NAME_VAR (ssa_name)) == 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; } @@ -241,7 +249,7 @@ 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; } @@ -252,11 +260,32 @@ 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); } @@ -280,20 +309,22 @@ 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; @@ -307,15 +338,15 @@ 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, + err = verify_use (e->src, definition_block[SSA_NAME_VERSION (op)], op_p, phi, e->flags & EDGE_ABNORMAL, !is_gimple_reg (PHI_RESULT (phi)), 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; } @@ -342,57 +373,53 @@ error: static void verify_flow_insensitive_alias_info (void) { - size_t i; tree var; - bitmap visited = BITMAP_XMALLOC (); + 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; + VEC(tree,gc) *may_aliases; + tree alias; - var = referenced_var (i); ann = var_ann (var); may_aliases = ann->may_aliases; - for (j = 0; may_aliases && j < VARRAY_ACTIVE_SIZE (may_aliases); j++) + for (j = 0; VEC_iterate (tree, may_aliases, j, alias); j++) { - tree alias = VARRAY_TREE (may_aliases, j); - - bitmap_set_bit (visited, var_ann (alias)->uid); + bitmap_set_bit (visited, DECL_UID (alias)); if (!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++) + FOR_EACH_REFERENCED_VAR (var, rvi) { 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)) + if (!MTAG_P (var) + && ann->is_aliased + && !bitmap_bit_p (visited, DECL_UID (var))) { - error ("Addressable variable that is an alias tag but is not in any alias set."); + error ("addressable variable that is aliased but is not in any alias set"); goto err; } } - BITMAP_XFREE (visited); + BITMAP_FREE (visited); return; err: debug_variable (var); - internal_error ("verify_flow_insensitive_alias_info failed."); + internal_error ("verify_flow_insensitive_alias_info failed"); } @@ -432,17 +459,16 @@ 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; } @@ -450,7 +476,7 @@ verify_flow_sensitive_alias_info (void) && pi->name_mem_tag && !is_call_clobbered (pi->name_mem_tag)) { - error ("Pointer escapes but its name tag is not call-clobbered."); + error ("pointer escapes but its name tag is not call-clobbered"); goto err; } } @@ -459,10 +485,11 @@ 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); +DEF_VEC_P (bitmap); +DEF_VEC_ALLOC_P (bitmap,heap); /* Verify that all name tags have different points to sets. This algorithm takes advantage of the fact that every variable with the @@ -471,8 +498,8 @@ DEF_VEC_MALLOC_P (bitmap); 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 + Additionally, given a pointer P_i with name tag NMT and symbol tag + SMT, this function verified the alias set of SMT is a superset of the alias set of NMT. */ static void @@ -481,15 +508,15 @@ verify_name_tags (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_XMALLOC (); + VEC(tree,heap) *name_tag_reps = NULL; + VEC(bitmap,heap) *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++) { struct ptr_info_def *pi; - tree tmt, ptr = ssa_name (i); + tree smt, ptr = ssa_name (i); if (ptr == NULL_TREE) continue; @@ -508,35 +535,34 @@ verify_name_tags (void) if (pi->pt_vars == NULL) continue; - VEC_safe_push (tree, name_tag_reps, ptr); - VEC_safe_push (bitmap, pt_vars_for_reps, pi->pt_vars); + VEC_safe_push (tree, heap, name_tag_reps, ptr); + VEC_safe_push (bitmap, heap, pt_vars_for_reps, pi->pt_vars); - /* Verify that alias set of PTR's type tag is a superset of the + /* Verify that alias set of PTR's symbol 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) + smt = var_ann (SSA_NAME_VAR (ptr))->symbol_mem_tag; + if (smt) { size_t i; - varray_type aliases = var_ann (tmt)->may_aliases; + VEC(tree,gc) *aliases = var_ann (smt)->may_aliases; + tree alias; + 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); - } + for (i = 0; VEC_iterate (tree, aliases, i, alias); i++) + bitmap_set_bit (type_aliases, DECL_UID (alias)); - /* When grouping, we may have added PTR's type tag into the + /* When grouping, we may have added PTR's symbol 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); + positive, pretend that SMT is in its own alias set. */ + bitmap_set_bit (type_aliases, DECL_UID (smt)); if (bitmap_equal_p (type_aliases, pi->pt_vars)) continue; if (!bitmap_intersect_compl_p (type_aliases, pi->pt_vars)) { - error ("Alias set of a pointer's type tag should be a superset of the corresponding name tag"); - debug_variable (tmt); + error ("alias set of a pointer's symbol tag should be a superset of the corresponding name tag"); + debug_variable (smt); debug_variable (pi->name_mem_tag); goto err; } @@ -551,7 +577,7 @@ verify_name_tags (void) { if (bitmap_equal_p (first, second)) { - error ("Two different pointers with identical points-to sets but different name tags"); + error ("two different pointers with identical points-to sets but different name tags"); debug_variable (VEC_index (tree, name_tag_reps, j)); goto err; } @@ -574,7 +600,10 @@ verify_name_tags (void) } } - VEC_free (bitmap, pt_vars_for_reps); + /* We do not have to free the bitmaps or trees in the vectors, as + they are not owned by us. */ + VEC_free (bitmap, heap, pt_vars_for_reps); + VEC_free (tree, heap, name_tag_reps); BITMAP_FREE (type_aliases); return; @@ -584,6 +613,46 @@ err: } +/* Verify the consistency of call clobbering information. */ +static void +verify_call_clobbering (void) +{ + unsigned int i; + bitmap_iterator bi; + tree var; + referenced_var_iterator rvi; + + /* At all times, the result of the DECL_CALL_CLOBBERED flag should + match the result of the call_clobbered_vars bitmap. Verify both + that everything in call_clobbered_vars is marked + DECL_CALL_CLOBBERED, and that everything marked + DECL_CALL_CLOBBERED is in call_clobbered_vars. */ + EXECUTE_IF_SET_IN_BITMAP (call_clobbered_vars, 0, i, bi) + { + var = referenced_var (i); + if (!MTAG_P (var) && !DECL_CALL_CLOBBERED (var)) + { + error ("variable in call_clobbered_vars but not marked DECL_CALL_CLOBBERED"); + debug_variable (var); + goto err; + } + } + FOR_EACH_REFERENCED_VAR (var, rvi) + { + if (!MTAG_P (var) && DECL_CALL_CLOBBERED (var) + && !bitmap_bit_p (call_clobbered_vars, DECL_UID (var))) + { + error ("variable marked DECL_CALL_CLOBBERED but not in call_clobbered_vars bitmap."); + debug_variable (var); + goto err; + } + } + return; + + err: + internal_error ("verify_call_clobbering failed"); +} + /* Verify the consistency of aliasing information. */ static void @@ -591,6 +660,7 @@ verify_alias_info (void) { verify_flow_sensitive_alias_info (); verify_name_tags (); + verify_call_clobbering (); verify_flow_insensitive_alias_info (); } @@ -599,15 +669,19 @@ 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]; - bitmap names_defined_in_bb = BITMAP_XMALLOC (); + bitmap names_defined_in_bb = BITMAP_ALLOC (NULL); + + gcc_assert (!need_ssa_update_p ()); + + verify_stmts (); timevar_push (TV_TREE_SSA_VERIFY); @@ -647,7 +721,7 @@ 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; } @@ -666,29 +740,47 @@ 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) == MODIFY_EXPR + && TREE_CODE (TREE_OPERAND (stmt, 0)) != SSA_NAME) + { + tree lhs, base_address; + + lhs = TREE_OPERAND (stmt, 0); + base_address = get_base_address (lhs); + + if (base_address + && SSA_VAR_P (base_address) + && ZERO_SSA_OPERANDS (stmt, SSA_OP_VMAYDEF|SSA_OP_VMUSTDEF)) { - error ("Statement makes aliased stores, but has no V_MAY_DEFS"); + error ("statement makes a memory store, but has no " + "V_MAY_DEFS nor V_MUST_DEFS"); print_generic_stmt (stderr, stmt, TDF_VOPS); 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_ALL_USES | SSA_OP_ALL_KILLS) { + op = USE_FROM_PTR (use_p); if (verify_use (bb, definition_block[SSA_NAME_VERSION (op)], - op, stmt, false, !is_gimple_reg (op), + use_p, stmt, false, !is_gimple_reg (op), 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); @@ -698,6 +790,7 @@ verify_ssa (void) 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) @@ -705,12 +798,30 @@ verify_ssa (void) else dom_computed[CDI_DOMINATORS] = orig_dom_state; - BITMAP_XFREE (names_defined_in_bb); + 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; } @@ -719,13 +830,16 @@ err: void init_tree_ssa (void) { - VARRAY_TREE_INIT (referenced_vars, 20, "referenced_vars"); - call_clobbered_vars = BITMAP_XMALLOC (); - addressable_vars = BITMAP_XMALLOC (); - init_ssa_operands (); + referenced_vars = htab_create_ggc (20, int_tree_map_hash, + int_tree_map_eq, NULL); + default_defs = htab_create_ggc (20, int_tree_map_hash, int_tree_map_eq, NULL); + call_clobbered_vars = BITMAP_ALLOC (NULL); + addressable_vars = BITMAP_ALLOC (NULL); + init_alias_heapvars (); init_ssanames (); init_phinodes (); global_var = NULL_TREE; + aliases_computed_p = false; } @@ -737,52 +851,79 @@ 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) + { + ggc_free (var->common.ann); + var->common.ann = NULL; } + htab_delete (referenced_vars); + referenced_vars = NULL; fini_ssanames (); fini_phinodes (); - fini_ssa_operands (); global_var = NULL_TREE; - BITMAP_XFREE (call_clobbered_vars); + + htab_delete (default_defs); + BITMAP_FREE (call_clobbered_vars); call_clobbered_vars = NULL; - BITMAP_XFREE (addressable_vars); + BITMAP_FREE (addressable_vars); addressable_vars = NULL; + modified_noreturn_calls = NULL; + aliases_computed_p = false; + delete_alias_heapvars (); + gcc_assert (!need_ssa_update_p ()); } -/* Return true if EXPR is a useless type conversion, otherwise return - false. */ +/* Return true if the conversion from INNER_TYPE to OUTER_TYPE is a + useless type conversion, otherwise return false. */ bool tree_ssa_useless_type_conversion_1 (tree outer_type, tree inner_type) { + if (inner_type == 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 (inner_type == outer_type - || (lang_hooks.types_compatible_p (inner_type, outer_type))) + if (lang_hooks.types_compatible_p (inner_type, outer_type)) return true; /* If both types are pointers and the outer type is a (void *), then @@ -793,17 +934,25 @@ tree_ssa_useless_type_conversion_1 (tree outer_type, tree inner_type) implement the ABI. */ else if (POINTER_TYPE_P (inner_type) && POINTER_TYPE_P (outer_type) - && TYPE_MODE (inner_type) == TYPE_MODE (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; - /* Pointers and references are equivalent once we get to GENERIC, - so strip conversions that just switch between them. */ + /* Don't lose casts between pointers to volatile and non-volatile + qualified types. Doing so would result in changing the semantics + of later accesses. */ + else if (POINTER_TYPE_P (inner_type) + && POINTER_TYPE_P (outer_type) + && TYPE_VOLATILE (TREE_TYPE (outer_type)) + != TYPE_VOLATILE (TREE_TYPE (inner_type))) + return false; + + /* Pointers/references are equivalent if their pointed to types + are effectively the same. This allows to strip conversions between + pointer types with different type qualifiers. */ else if (POINTER_TYPE_P (inner_type) && POINTER_TYPE_P (outer_type) - && TYPE_MODE (inner_type) == TYPE_MODE (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), @@ -819,9 +968,10 @@ tree_ssa_useless_type_conversion_1 (tree outer_type, tree inner_type) mean that testing of precision is necessary. */ else if (INTEGRAL_TYPE_P (inner_type) && INTEGRAL_TYPE_P (outer_type) - && TYPE_MODE (inner_type) == TYPE_MODE (outer_type) && TYPE_UNSIGNED (inner_type) == TYPE_UNSIGNED (outer_type) - && TYPE_PRECISION (inner_type) == TYPE_PRECISION (outer_type)) + && TYPE_PRECISION (inner_type) == TYPE_PRECISION (outer_type) + && simple_cst_equal (TYPE_MAX_VALUE (inner_type), TYPE_MAX_VALUE (outer_type)) + && simple_cst_equal (TYPE_MIN_VALUE (inner_type), TYPE_MIN_VALUE (outer_type))) { bool first_boolean = (TREE_CODE (inner_type) == BOOLEAN_TYPE); bool second_boolean = (TREE_CODE (outer_type) == BOOLEAN_TYPE); @@ -865,17 +1015,12 @@ tree_ssa_useless_type_conversion (tree expr) bool stmt_references_memory_p (tree stmt) { - stmt_ann_t ann; - - get_stmt_operands (stmt); - ann = stmt_ann (stmt); + stmt_ann_t 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); + return (!ZERO_SSA_OPERANDS (stmt, SSA_OP_ALL_VIRTUALS)); } /* Internal helper for walk_use_def_chains. VAR, FN and DATA are as @@ -984,332 +1129,6 @@ walk_use_def_chains (tree var, walk_use_def_chains_fn fn, void *data, } } - -/* 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); - 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) -{ - 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); - } - - /* And remove the dead phis. */ - 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)) - { - stmt = SSA_NAME_DEF_STMT (ssa_name (i)); - remove_phi_node (stmt, NULL_TREE, bb_for_stmt (stmt)); - } - } - - free_df (); - free (eq_to); -} - -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. @@ -1330,10 +1149,12 @@ 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); + tree context = (tree) data; + location_t *locus, *fun_locus; /* Default uses (indicated by an empty definition statement), are uninitialized. */ @@ -1353,9 +1174,16 @@ 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 (0, gmsgid, locus, var); + fun_locus = &DECL_SOURCE_LOCATION (cfun->decl); + if (locus->file != fun_locus->file + || locus->line < fun_locus->line + || locus->line > cfun->function_end_locus.line) + inform ("%J%qD was declared here", var, var); + TREE_NO_WARNING (var) = 1; } @@ -1365,17 +1193,31 @@ warn_uninit (tree t, const char *msgid, location_t *locus) static tree warn_uninitialized_var (tree *tp, int *walk_subtrees, void *data) { - location_t *locus = 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. */ + warn_uninit (t, "%H%qD is used uninitialized in this function", data); *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; } @@ -1401,7 +1243,7 @@ warn_uninitialized_phi (tree phi) } } -static void +static unsigned int execute_early_warn_uninitialized (void) { block_stmt_iterator bsi; @@ -1409,11 +1251,15 @@ execute_early_warn_uninitialized (void) 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); + { + tree context = bsi_stmt (bsi); + walk_tree (bsi_stmt_ptr (bsi), warn_uninitialized_var, + context, NULL); + } + return 0; } -static void +static unsigned int execute_late_warn_uninitialized (void) { basic_block bb; @@ -1427,6 +1273,7 @@ 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