X-Git-Url: http://git.sourceforge.jp/view?p=pf3gnuchains%2Fgcc-fork.git;a=blobdiff_plain;f=gcc%2Ftree-ssa.c;h=7bd01f8d4dbac7f023d8ce50fedaacd6d56f4d0e;hp=13a79dcf39a35bd00fee45101784a50ed4235cf1;hb=b7de3a95380bc054e113944886dac56caa025972;hpb=a9538d681b63fb9ff2291c3fde1ddd1ab389576c diff --git a/gcc/tree-ssa.c b/gcc/tree-ssa.c index 13a79dcf39a..7bd01f8d4db 100644 --- a/gcc/tree-ssa.c +++ b/gcc/tree-ssa.c @@ -1,5 +1,5 @@ /* Miscellaneous SSA utility functions. - Copyright (C) 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009 + Copyright (C) 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009, 2010 Free Software Foundation, Inc. This file is part of GCC. @@ -24,27 +24,25 @@ along with GCC; see the file COPYING3. If not see #include "tm.h" #include "tree.h" #include "flags.h" -#include "rtl.h" #include "tm_p.h" +#include "target.h" #include "ggc.h" #include "langhooks.h" -#include "hard-reg-set.h" #include "basic-block.h" #include "output.h" -#include "expr.h" #include "function.h" -#include "diagnostic.h" +#include "tree-pretty-print.h" +#include "gimple-pretty-print.h" #include "bitmap.h" #include "pointer-set.h" #include "tree-flow.h" #include "gimple.h" #include "tree-inline.h" -#include "varray.h" #include "timevar.h" #include "hashtab.h" #include "tree-dump.h" #include "tree-pass.h" -#include "toplev.h" +#include "diagnostic-core.h" /* Pointer map of variable mappings, keyed by edge. */ static struct pointer_map_t *edge_var_maps; @@ -53,7 +51,7 @@ 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) +redirect_edge_var_map_add (edge e, tree result, tree def, source_location locus) { void **slot; edge_var_map_vector old_head, head; @@ -71,6 +69,7 @@ redirect_edge_var_map_add (edge e, tree result, tree def) } new_node.def = def; new_node.result = result; + new_node.locus = locus; VEC_safe_push (edge_var_map, heap, head, &new_node); if (old_head != head) @@ -193,14 +192,16 @@ ssa_redirect_edge (edge e, basic_block dest) for (gsi = gsi_start_phis (e->dest); !gsi_end_p (gsi); gsi_next (&gsi)) { tree def; + source_location locus ; phi = gsi_stmt (gsi); def = gimple_phi_arg_def (phi, e->dest_idx); + locus = gimple_phi_arg_location (phi, e->dest_idx); if (def == NULL_TREE) continue; - redirect_edge_var_map_add (e, gimple_phi_result (phi), def); + redirect_edge_var_map_add (e, gimple_phi_result (phi), def, locus); } e = redirect_edge_succ_nodup (e, dest); @@ -233,12 +234,337 @@ flush_pending_stmts (edge e) phi = gsi_stmt (gsi); def = redirect_edge_var_map_def (vm); - add_phi_arg (phi, def, e); + add_phi_arg (phi, def, e, redirect_edge_var_map_location (vm)); } redirect_edge_var_map_clear (e); } +/* Given a tree for an expression for which we might want to emit + locations or values in debug information (generally a variable, but + we might deal with other kinds of trees in the future), return the + tree that should be used as the variable of a DEBUG_BIND STMT or + VAR_LOCATION INSN or NOTE. Return NULL if VAR is not to be tracked. */ + +tree +target_for_debug_bind (tree var) +{ + if (!MAY_HAVE_DEBUG_STMTS) + return NULL_TREE; + + if (TREE_CODE (var) != VAR_DECL + && TREE_CODE (var) != PARM_DECL) + return NULL_TREE; + + if (DECL_HAS_VALUE_EXPR_P (var)) + return target_for_debug_bind (DECL_VALUE_EXPR (var)); + + if (DECL_IGNORED_P (var)) + return NULL_TREE; + + if (!is_gimple_reg (var)) + return NULL_TREE; + + return var; +} + +/* Called via walk_tree, look for SSA_NAMEs that have already been + released. */ + +static tree +find_released_ssa_name (tree *tp, int *walk_subtrees, void *data_) +{ + struct walk_stmt_info *wi = (struct walk_stmt_info *) data_; + + if (wi && wi->is_lhs) + return NULL_TREE; + + if (TREE_CODE (*tp) == SSA_NAME) + { + if (SSA_NAME_IN_FREE_LIST (*tp)) + return *tp; + + *walk_subtrees = 0; + } + else if (IS_TYPE_OR_DECL_P (*tp)) + *walk_subtrees = 0; + + return NULL_TREE; +} + +/* Insert a DEBUG BIND stmt before the DEF of VAR if VAR is referenced + by other DEBUG stmts, and replace uses of the DEF with the + newly-created debug temp. */ + +void +insert_debug_temp_for_var_def (gimple_stmt_iterator *gsi, tree var) +{ + imm_use_iterator imm_iter; + use_operand_p use_p; + gimple stmt; + gimple def_stmt = NULL; + int usecount = 0; + tree value = NULL; + + if (!MAY_HAVE_DEBUG_STMTS) + return; + + /* If this name has already been registered for replacement, do nothing + as anything that uses this name isn't in SSA form. */ + if (name_registered_for_update_p (var)) + return; + + /* Check whether there are debug stmts that reference this variable and, + if there are, decide whether we should use a debug temp. */ + FOR_EACH_IMM_USE_FAST (use_p, imm_iter, var) + { + stmt = USE_STMT (use_p); + + if (!gimple_debug_bind_p (stmt)) + continue; + + if (usecount++) + break; + + if (gimple_debug_bind_get_value (stmt) != var) + { + /* Count this as an additional use, so as to make sure we + use a temp unless VAR's definition has a SINGLE_RHS that + can be shared. */ + usecount++; + break; + } + } + + if (!usecount) + return; + + if (gsi) + def_stmt = gsi_stmt (*gsi); + else + def_stmt = SSA_NAME_DEF_STMT (var); + + /* If we didn't get an insertion point, and the stmt has already + been removed, we won't be able to insert the debug bind stmt, so + we'll have to drop debug information. */ + if (gimple_code (def_stmt) == GIMPLE_PHI) + { + value = degenerate_phi_result (def_stmt); + if (value && walk_tree (&value, find_released_ssa_name, NULL, NULL)) + value = NULL; + } + else if (is_gimple_assign (def_stmt)) + { + bool no_value = false; + + if (!dom_info_available_p (CDI_DOMINATORS)) + { + struct walk_stmt_info wi; + + memset (&wi, 0, sizeof (wi)); + + /* When removing blocks without following reverse dominance + order, we may sometimes encounter SSA_NAMEs that have + already been released, referenced in other SSA_DEFs that + we're about to release. Consider: + + : + v_1 = foo; + + : + w_2 = v_1 + bar; + # DEBUG w => w_2 + + If we deleted BB X first, propagating the value of w_2 + won't do us any good. It's too late to recover their + original definition of v_1: when it was deleted, it was + only referenced in other DEFs, it couldn't possibly know + it should have been retained, and propagating every + single DEF just in case it might have to be propagated + into a DEBUG STMT would probably be too wasteful. + + When dominator information is not readily available, we + check for and accept some loss of debug information. But + if it is available, there's no excuse for us to remove + blocks in the wrong order, so we don't even check for + dead SSA NAMEs. SSA verification shall catch any + errors. */ + if ((!gsi && !gimple_bb (def_stmt)) + || walk_gimple_op (def_stmt, find_released_ssa_name, &wi)) + no_value = true; + } + + if (!no_value) + value = gimple_assign_rhs_to_tree (def_stmt); + } + + if (value) + { + /* If there's a single use of VAR, and VAR is the entire debug + expression (usecount would have been incremented again + otherwise), and the definition involves only constants and + SSA names, then we can propagate VALUE into this single use, + avoiding the temp. + + We can also avoid using a temp if VALUE can be shared and + propagated into all uses, without generating expressions that + wouldn't be valid gimple RHSs. + + Other cases that would require unsharing or non-gimple RHSs + are deferred to a debug temp, although we could avoid temps + at the expense of duplication of expressions. */ + + if (CONSTANT_CLASS_P (value) + || gimple_code (def_stmt) == GIMPLE_PHI + || (usecount == 1 + && (!gimple_assign_single_p (def_stmt) + || is_gimple_min_invariant (value))) + || is_gimple_reg (value)) + value = unshare_expr (value); + else + { + gimple def_temp; + tree vexpr = make_node (DEBUG_EXPR_DECL); + + def_temp = gimple_build_debug_bind (vexpr, + unshare_expr (value), + def_stmt); + + DECL_ARTIFICIAL (vexpr) = 1; + TREE_TYPE (vexpr) = TREE_TYPE (value); + if (DECL_P (value)) + DECL_MODE (vexpr) = DECL_MODE (value); + else + DECL_MODE (vexpr) = TYPE_MODE (TREE_TYPE (value)); + + if (gsi) + gsi_insert_before (gsi, def_temp, GSI_SAME_STMT); + else + { + gimple_stmt_iterator ngsi = gsi_for_stmt (def_stmt); + gsi_insert_before (&ngsi, def_temp, GSI_SAME_STMT); + } + + value = vexpr; + } + } + + FOR_EACH_IMM_USE_STMT (stmt, imm_iter, var) + { + if (!gimple_debug_bind_p (stmt)) + continue; + + if (value) + FOR_EACH_IMM_USE_ON_STMT (use_p, imm_iter) + /* unshare_expr is not needed here. vexpr is either a + SINGLE_RHS, that can be safely shared, some other RHS + that was unshared when we found it had a single debug + use, or a DEBUG_EXPR_DECL, that can be safely + shared. */ + SET_USE (use_p, value); + else + gimple_debug_bind_reset_value (stmt); + + update_stmt (stmt); + } +} + + +/* Insert a DEBUG BIND stmt before STMT for each DEF referenced by + other DEBUG stmts, and replace uses of the DEF with the + newly-created debug temp. */ + +void +insert_debug_temps_for_defs (gimple_stmt_iterator *gsi) +{ + gimple stmt; + ssa_op_iter op_iter; + def_operand_p def_p; + + if (!MAY_HAVE_DEBUG_STMTS) + return; + + stmt = gsi_stmt (*gsi); + + FOR_EACH_PHI_OR_STMT_DEF (def_p, stmt, op_iter, SSA_OP_DEF) + { + tree var = DEF_FROM_PTR (def_p); + + if (TREE_CODE (var) != SSA_NAME) + continue; + + insert_debug_temp_for_var_def (gsi, var); + } +} + +/* Delete SSA DEFs for SSA versions in the TOREMOVE bitmap, removing + dominated stmts before their dominators, so that release_ssa_defs + stands a chance of propagating DEFs into debug bind stmts. */ + +void +release_defs_bitset (bitmap toremove) +{ + unsigned j; + bitmap_iterator bi; + + /* Performing a topological sort is probably overkill, this will + most likely run in slightly superlinear time, rather than the + pathological quadratic worst case. */ + while (!bitmap_empty_p (toremove)) + EXECUTE_IF_SET_IN_BITMAP (toremove, 0, j, bi) + { + bool remove_now = true; + tree var = ssa_name (j); + gimple stmt; + imm_use_iterator uit; + + FOR_EACH_IMM_USE_STMT (stmt, uit, var) + { + ssa_op_iter dit; + def_operand_p def_p; + + /* We can't propagate PHI nodes into debug stmts. */ + if (gimple_code (stmt) == GIMPLE_PHI + || is_gimple_debug (stmt)) + continue; + + /* If we find another definition to remove that uses + the one we're looking at, defer the removal of this + one, so that it can be propagated into debug stmts + after the other is. */ + FOR_EACH_SSA_DEF_OPERAND (def_p, stmt, dit, SSA_OP_DEF) + { + tree odef = DEF_FROM_PTR (def_p); + + if (bitmap_bit_p (toremove, SSA_NAME_VERSION (odef))) + { + remove_now = false; + break; + } + } + + if (!remove_now) + BREAK_FROM_IMM_USE_STMT (uit); + } + + if (remove_now) + { + gimple def = SSA_NAME_DEF_STMT (var); + gimple_stmt_iterator gsi = gsi_for_stmt (def); + + if (gimple_code (def) == GIMPLE_PHI) + remove_phi_node (&gsi, true); + else + { + gsi_remove (&gsi, true); + release_defs (def); + } + + bitmap_clear_bit (toremove, j); + } + } +} + /* Return true if SSA_NAME is malformed and mark it visited. IS_VIRTUAL is true if this SSA_NAME was found inside a virtual @@ -312,6 +638,13 @@ verify_def (basic_block bb, basic_block *definition_block, tree ssa_name, if (verify_ssa_name (ssa_name, is_virtual)) goto err; + if (TREE_CODE (SSA_NAME_VAR (ssa_name)) == RESULT_DECL + && DECL_BY_REFERENCE (SSA_NAME_VAR (ssa_name))) + { + error ("RESULT_DECL should be read only when DECL_BY_REFERENCE is set"); + goto err; + } + if (definition_block[SSA_NAME_VERSION (ssa_name)]) { error ("SSA_NAME created in two different blocks %i and %i", @@ -400,7 +733,7 @@ verify_use (basic_block bb, basic_block def_bb, use_operand_p use_p, err = true; } - /* Make sure the use is in an appropriate list by checking the previous + /* 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) { @@ -529,7 +862,7 @@ error: /* Verify common invariants in the SSA web. TODO: verify the variable annotations. */ -void +DEBUG_FUNCTION void verify_ssa (bool check_modified_stmt) { size_t i; @@ -605,6 +938,8 @@ verify_ssa (bool check_modified_stmt) gimple stmt = gsi_stmt (gsi); use_operand_p use_p; bool has_err; + int count; + unsigned i; if (check_modified_stmt && gimple_modified_p (stmt)) { @@ -632,6 +967,9 @@ verify_ssa (bool check_modified_stmt) goto err; } } + else if (gimple_debug_bind_p (stmt) + && !gimple_debug_bind_has_value_p (stmt)) + continue; /* Verify the single virtual operand and its constraints. */ has_err = false; @@ -671,6 +1009,7 @@ verify_ssa (bool check_modified_stmt) goto err; } + count = 0; FOR_EACH_SSA_TREE_OPERAND (op, stmt, iter, SSA_OP_USE|SSA_OP_DEF) { if (verify_ssa_name (op, false)) @@ -679,6 +1018,19 @@ verify_ssa (bool check_modified_stmt) print_gimple_stmt (stderr, stmt, 0, TDF_VOPS|TDF_MEMSYMS); goto err; } + count++; + } + + for (i = 0; i < gimple_num_ops (stmt); i++) + { + op = gimple_op (stmt, i); + if (op && TREE_CODE (op) == SSA_NAME && --count < 0) + { + error ("number of operands and imm-links don%'t agree" + " in statement"); + print_gimple_stmt (stderr, stmt, 0, TDF_VOPS|TDF_MEMSYMS); + goto err; + } } FOR_EACH_SSA_USE_OPERAND (use_p, stmt, iter, SSA_OP_USE|SSA_OP_VUSE) @@ -716,7 +1068,7 @@ verify_ssa (bool check_modified_stmt) free_dominance_info (CDI_DOMINATORS); else set_dom_info_availability (CDI_DOMINATORS, orig_dom_state); - + BITMAP_FREE (names_defined_in_bb); timevar_pop (TV_TREE_SSA_VERIFY); return; @@ -785,13 +1137,12 @@ uid_ssaname_map_hash (const void *item) void init_tree_ssa (struct function *fn) { - fn->gimple_df = GGC_CNEW (struct gimple_df); - fn->gimple_df->referenced_vars = htab_create_ggc (20, uid_decl_map_hash, + fn->gimple_df = ggc_alloc_cleared_gimple_df (); + fn->gimple_df->referenced_vars = htab_create_ggc (20, uid_decl_map_hash, uid_decl_map_eq, NULL); - fn->gimple_df->default_defs = htab_create_ggc (20, uid_ssaname_map_hash, + fn->gimple_df->default_defs = htab_create_ggc (20, uid_ssaname_map_hash, uid_ssaname_map_eq, NULL); pt_solution_reset (&fn->gimple_df->escaped); - pt_solution_reset (&fn->gimple_df->callused); init_ssanames (fn, 0); init_phinodes (); } @@ -802,60 +1153,19 @@ init_tree_ssa (struct function *fn) void delete_tree_ssa (void) { - size_t i; - basic_block bb; - gimple_stmt_iterator gsi; 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); - } - - /* FIXME. This may not be necessary. We will release all this - memory en masse in free_ssa_operands. This clearing used to be - necessary to avoid problems with the inliner, but it may not be - needed anymore. */ - FOR_EACH_BB (bb) - { - for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi)) - { - gimple stmt = gsi_stmt (gsi); - - if (gimple_has_ops (stmt)) - { - gimple_set_def_ops (stmt, NULL); - gimple_set_use_ops (stmt, NULL); - } - - if (gimple_has_mem_ops (stmt)) - { - gimple_set_vdef (stmt, NULL_TREE); - gimple_set_vuse (stmt, NULL_TREE); - } - - gimple_set_modified (stmt, true); - } - if (!(bb->flags & BB_RTL)) - set_phi_nodes (bb, NULL); - } - /* Remove annotations from every referenced local variable. */ FOR_EACH_REFERENCED_VAR (var, rvi) { if (is_global_var (var)) continue; - if (var->base.ann) - ggc_free (var->base.ann); - var->base.ann = NULL; + if (var_ann (var)) + { + ggc_free (var_ann (var)); + *DECL_VAR_ANN_PTR (var) = NULL; + } } htab_delete (gimple_referenced_vars (cfun)); cfun->gimple_df->referenced_vars = NULL; @@ -872,7 +1182,9 @@ delete_tree_ssa (void) htab_delete (cfun->gimple_df->default_defs); cfun->gimple_df->default_defs = NULL; pt_solution_reset (&cfun->gimple_df->escaped); - pt_solution_reset (&cfun->gimple_df->callused); + if (cfun->gimple_df->decls_to_pointers != NULL) + pointer_map_destroy (cfun->gimple_df->decls_to_pointers); + cfun->gimple_df->decls_to_pointers = NULL; cfun->gimple_df->modified_noreturn_calls = NULL; cfun->gimple_df = NULL; @@ -880,20 +1192,59 @@ delete_tree_ssa (void) redirect_edge_var_map_destroy (); } -/* Helper function for useless_type_conversion_p. */ +/* 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. -static bool -useless_type_conversion_p_1 (tree outer_type, tree inner_type) + 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) { /* Do the following before stripping toplevel qualifiers. */ if (POINTER_TYPE_P (inner_type) && POINTER_TYPE_P (outer_type)) { + /* Do not lose casts between pointers to different address spaces. */ + if (TYPE_ADDR_SPACE (TREE_TYPE (outer_type)) + != TYPE_ADDR_SPACE (TREE_TYPE (inner_type))) + return false; + /* Do not lose casts to restrict qualified pointers. */ if ((TYPE_RESTRICT (outer_type) != TYPE_RESTRICT (inner_type)) && TYPE_RESTRICT (outer_type)) return false; + + /* If the outer type is (void *) or a pointer to an incomplete + record type or a pointer to an unprototyped function, + then the conversion is not necessary. */ + if (VOID_TYPE_P (TREE_TYPE (outer_type)) + || ((TREE_CODE (TREE_TYPE (outer_type)) == FUNCTION_TYPE + || TREE_CODE (TREE_TYPE (outer_type)) == METHOD_TYPE) + && (TREE_CODE (TREE_TYPE (outer_type)) + == TREE_CODE (TREE_TYPE (inner_type))) + && !prototype_p (TREE_TYPE (outer_type)) + && useless_type_conversion_p (TREE_TYPE (TREE_TYPE (outer_type)), + TREE_TYPE (TREE_TYPE (inner_type))))) + return true; } /* From now on qualifiers on value types do not matter. */ @@ -908,8 +1259,10 @@ useless_type_conversion_p_1 (tree outer_type, tree 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)) + /* Changes in machine mode are never useless conversions unless we + deal with aggregate types in which case we defer to later checks. */ + if (TYPE_MODE (inner_type) != TYPE_MODE (outer_type) + && !AGGREGATE_TYPE_P (inner_type)) return false; /* If both the inner and outer types are integral types, then the @@ -934,37 +1287,27 @@ useless_type_conversion_p_1 (tree outer_type, tree inner_type) && SCALAR_FLOAT_TYPE_P (outer_type)) return true; + /* Fixed point types with the same mode are compatible. */ + else if (FIXED_POINT_TYPE_P (inner_type) + && FIXED_POINT_TYPE_P (outer_type)) + return true; + /* We need to take special care recursing to pointed-to types. */ else if (POINTER_TYPE_P (inner_type) && POINTER_TYPE_P (outer_type)) { - /* Don't lose casts between pointers to volatile and non-volatile - qualified types. Doing so would result in changing the semantics - of later accesses. For function types the volatile qualifier - is used to indicate noreturn functions. */ - if (TREE_CODE (TREE_TYPE (outer_type)) != FUNCTION_TYPE - && TREE_CODE (TREE_TYPE (outer_type)) != METHOD_TYPE - && TREE_CODE (TREE_TYPE (inner_type)) != FUNCTION_TYPE - && TREE_CODE (TREE_TYPE (inner_type)) != METHOD_TYPE - && (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 that when dereferenced access - memory with different alias sets. */ - if (get_deref_alias_set (inner_type) != get_deref_alias_set (outer_type)) + /* Do not lose casts to function pointer types. */ + if ((TREE_CODE (TREE_TYPE (outer_type)) == FUNCTION_TYPE + || TREE_CODE (TREE_TYPE (outer_type)) == METHOD_TYPE) + && !useless_type_conversion_p (TREE_TYPE (outer_type), + TREE_TYPE (inner_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. */ - /* 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)); + /* Otherwise pointers/references are equivalent. */ + return true; } /* Recurse for complex types. */ @@ -980,72 +1323,128 @@ useless_type_conversion_p_1 (tree outer_type, tree inner_type) return useless_type_conversion_p (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)) + else if (TREE_CODE (inner_type) == ARRAY_TYPE + && TREE_CODE (outer_type) == ARRAY_TYPE) { - /* Different types of aggregates are incompatible. */ - if (TREE_CODE (inner_type) != TREE_CODE (outer_type)) + /* Preserve string attributes. */ + if (TYPE_STRING_FLAG (inner_type) != TYPE_STRING_FLAG (outer_type)) return false; /* Conversions from array types with unknown extent to array types with known extent are not useless. */ - if (TREE_CODE (inner_type) == ARRAY_TYPE - && !TYPE_DOMAIN (inner_type) + if (!TYPE_DOMAIN (inner_type) && TYPE_DOMAIN (outer_type)) return false; - /* ??? This seems to be necessary even for aggregates that don't - have TYPE_STRUCTURAL_EQUALITY_P set. */ + /* Nor are conversions from array types with non-constant size to + array types with constant size or to different size. */ + if (TYPE_SIZE (outer_type) + && TREE_CODE (TYPE_SIZE (outer_type)) == INTEGER_CST + && (!TYPE_SIZE (inner_type) + || TREE_CODE (TYPE_SIZE (inner_type)) != INTEGER_CST + || !tree_int_cst_equal (TYPE_SIZE (outer_type), + TYPE_SIZE (inner_type)))) + return false; - /* ??? This should eventually just return false. */ - return lang_hooks.types_compatible_p (inner_type, outer_type); + /* Check conversions between arrays with partially known extents. + If the array min/max values are constant they have to match. + Otherwise allow conversions to unknown and variable extents. + In particular this declares conversions that may change the + mode to BLKmode as useless. */ + if (TYPE_DOMAIN (inner_type) + && TYPE_DOMAIN (outer_type) + && TYPE_DOMAIN (inner_type) != TYPE_DOMAIN (outer_type)) + { + tree inner_min = TYPE_MIN_VALUE (TYPE_DOMAIN (inner_type)); + tree outer_min = TYPE_MIN_VALUE (TYPE_DOMAIN (outer_type)); + tree inner_max = TYPE_MAX_VALUE (TYPE_DOMAIN (inner_type)); + tree outer_max = TYPE_MAX_VALUE (TYPE_DOMAIN (outer_type)); + + /* After gimplification a variable min/max value carries no + additional information compared to a NULL value. All that + matters has been lowered to be part of the IL. */ + if (inner_min && TREE_CODE (inner_min) != INTEGER_CST) + inner_min = NULL_TREE; + if (outer_min && TREE_CODE (outer_min) != INTEGER_CST) + outer_min = NULL_TREE; + if (inner_max && TREE_CODE (inner_max) != INTEGER_CST) + inner_max = NULL_TREE; + if (outer_max && TREE_CODE (outer_max) != INTEGER_CST) + outer_max = NULL_TREE; + + /* Conversions NULL / variable <- cst are useless, but not + the other way around. */ + if (outer_min + && (!inner_min + || !tree_int_cst_equal (inner_min, outer_min))) + return false; + if (outer_max + && (!inner_max + || !tree_int_cst_equal (inner_max, outer_max))) + return false; + } + + /* Recurse on the element check. */ + return useless_type_conversion_p (TREE_TYPE (outer_type), + TREE_TYPE (inner_type)); } - /* Also for functions and possibly other types with - TYPE_STRUCTURAL_EQUALITY_P set. */ - else if (TYPE_STRUCTURAL_EQUALITY_P (inner_type) - && TYPE_STRUCTURAL_EQUALITY_P (outer_type)) - 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. + else if ((TREE_CODE (inner_type) == FUNCTION_TYPE + || TREE_CODE (inner_type) == METHOD_TYPE) + && TREE_CODE (inner_type) == TREE_CODE (outer_type)) + { + tree outer_parm, inner_parm; - 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: + /* If the return types are not compatible bail out. */ + if (!useless_type_conversion_p (TREE_TYPE (outer_type), + TREE_TYPE (inner_type))) + return false; - 1) useless_type_conversion_p is transitive. - If a < b and b < c then a < c. + /* Method types should belong to a compatible base class. */ + if (TREE_CODE (inner_type) == METHOD_TYPE + && !useless_type_conversion_p (TYPE_METHOD_BASETYPE (outer_type), + TYPE_METHOD_BASETYPE (inner_type))) + return false; - 2) useless_type_conversion_p is not symmetric. - From a < b does not follow a > b. + /* A conversion to an unprototyped argument list is ok. */ + if (!prototype_p (outer_type)) + return true; + + /* If the unqualified argument types are compatible the conversion + is useless. */ + if (TYPE_ARG_TYPES (outer_type) == TYPE_ARG_TYPES (inner_type)) + return true; + + for (outer_parm = TYPE_ARG_TYPES (outer_type), + inner_parm = TYPE_ARG_TYPES (inner_type); + outer_parm && inner_parm; + outer_parm = TREE_CHAIN (outer_parm), + inner_parm = TREE_CHAIN (inner_parm)) + if (!useless_type_conversion_p + (TYPE_MAIN_VARIANT (TREE_VALUE (outer_parm)), + TYPE_MAIN_VARIANT (TREE_VALUE (inner_parm)))) + return false; + + /* If there is a mismatch in the number of arguments the functions + are not compatible. */ + if (outer_parm || inner_parm) + return false; - 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. */ + /* Defer to the target if necessary. */ + if (TYPE_ATTRIBUTES (inner_type) || TYPE_ATTRIBUTES (outer_type)) + return targetm.comp_type_attributes (outer_type, inner_type) != 0; -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 true; + } + + /* For aggregates we rely on TYPE_CANONICAL exclusively and require + explicit conversions for types involving to be structurally + compared types. */ + else if (AGGREGATE_TYPE_P (inner_type) + && TREE_CODE (inner_type) == TREE_CODE (outer_type)) + return false; - return useless_type_conversion_p_1 (outer_type, inner_type); + return false; } /* Return true if a conversion from either type of TYPE1 and TYPE2 @@ -1079,10 +1478,22 @@ tree_ssa_useless_type_conversion (tree expr) return false; } +/* Strip conversions from EXP according to + tree_ssa_useless_type_conversion and return the resulting + expression. */ + +tree +tree_ssa_strip_useless_type_conversions (tree exp) +{ + while (tree_ssa_useless_type_conversion (exp)) + exp = TREE_OPERAND (exp, 0); + return exp; +} + /* Internal helper for walk_use_def_chains. VAR, FN and DATA are as described in walk_use_def_chains. - + VISITED is a pointer set used to mark visited SSA_NAMEs to avoid infinite loops. We used to have a bitmap for this to just mark SSA versions we had visited. But non-sparse bitmaps are way too @@ -1140,10 +1551,10 @@ walk_use_def_chains_1 (tree var, walk_use_def_chains_fn fn, void *data, if (fn (gimple_phi_arg_def (def_stmt, i), def_stmt, data)) return true; } - + return false; } - + /* Walk use-def chains starting at the SSA variable VAR. Call @@ -1151,7 +1562,7 @@ walk_use_def_chains_1 (tree var, walk_use_def_chains_fn fn, void *data, arguments: VAR, its defining statement (DEF_STMT) and a generic pointer to whatever state information that FN may want to maintain (DATA). FN is able to stop the walk by returning true, otherwise - in order to continue the walk, FN should return false. + in order to continue the walk, FN should return false. Note, that if DEF_STMT is a PHI node, the semantics are slightly different. The first argument to FN is no longer the original @@ -1189,25 +1600,6 @@ 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. */ - -bool -ssa_undefined_value_p (tree t) -{ - tree var = SSA_NAME_VAR (t); - - /* Parameters get their initial value from the function entry. */ - if (TREE_CODE (var) == PARM_DECL) - return false; - - /* Hard register variables get their initial value from the ether. */ - if (TREE_CODE (var) == VAR_DECL && DECL_HARD_REGISTER (var)) - return false; - - /* The value is undefined iff its definition statement is empty. */ - return gimple_nop_p (SSA_NAME_DEF_STMT (t)); -} - /* Emit warnings for uninitialized variables. This is done in two passes. The first pass notices real uses of SSA names with undefined values. @@ -1226,7 +1618,7 @@ ssa_undefined_value_p (tree t) /* Emit a warning for T, an SSA_NAME, being uninitialized. The exact warning text is in MSGID and LOCUS may contain a location or be null. */ -static void +void warn_uninit (tree t, const char *gmsgid, void *data) { tree var = SSA_NAME_VAR (t); @@ -1245,7 +1637,7 @@ warn_uninit (tree t, const char *gmsgid, void *data) /* Do not warn if it can be initialized outside this module. */ if (is_global_var (var)) return; - + location = (context != NULL && gimple_has_location (context)) ? gimple_location (context) : DECL_SOURCE_LOCATION (var); @@ -1255,10 +1647,12 @@ warn_uninit (tree t, const char *gmsgid, void *data) { TREE_NO_WARNING (var) = 1; + if (location == DECL_SOURCE_LOCATION (var)) + return; if (xloc.file != floc.file || xloc.line < floc.line || xloc.line > LOCATION_LINE (cfun->function_end_locus)) - inform (input_location, "%J%qD was declared here", var, var); + inform (DECL_SOURCE_LOCATION (var), "%qD was declared here", var); } } @@ -1280,7 +1674,13 @@ warn_uninitialized_var (tree *tp, int *walk_subtrees, void *data_) /* We do not care about LHS. */ if (wi->is_lhs) - return NULL_TREE; + { + /* Except for operands of dereferences. */ + if (!INDIRECT_REF_P (t) + && TREE_CODE (t) != MEM_REF) + return NULL_TREE; + t = TREE_OPERAND (t, 0); + } switch (TREE_CODE (t)) { @@ -1297,7 +1697,7 @@ warn_uninitialized_var (tree *tp, int *walk_subtrees, void *data_) use_operand_p vuse; tree op; - /* If there is not gimple stmt, + /* If there is not gimple stmt, or alias information has not been computed, then we cannot check VUSE ops. */ if (data->stmt == NULL) @@ -1312,7 +1712,7 @@ warn_uninitialized_var (tree *tp, int *walk_subtrees, void *data_) return NULL_TREE; op = USE_FROM_PTR (vuse); - if (t != SSA_NAME_VAR (op) + if (t != SSA_NAME_VAR (op) || !SSA_NAME_IS_DEFAULT_DEF (op)) return NULL_TREE; /* If this is a VUSE of t and it is the default definition, @@ -1351,28 +1751,7 @@ warn_uninitialized_var (tree *tp, int *walk_subtrees, void *data_) return NULL_TREE; } -/* Look for inputs to PHI that are SSA_NAMEs that have empty definitions - and warn about them. */ - -static void -warn_uninitialized_phi (gimple phi) -{ - size_t i, n = gimple_phi_num_args (phi); - - /* Don't look at memory tags. */ - if (!is_gimple_reg (gimple_phi_result (phi))) - return; - - for (i = 0; i < n; ++i) - { - tree op = gimple_phi_arg_def (phi, i); - if (TREE_CODE (op) == SSA_NAME) - warn_uninit (op, "%qD may be used uninitialized in this function", - NULL); - } -} - -static unsigned int +unsigned int warn_uninitialized_vars (bool warn_possibly_uninitialized) { gimple_stmt_iterator gsi; @@ -1381,7 +1760,6 @@ warn_uninitialized_vars (bool warn_possibly_uninitialized) data.warn_possibly_uninitialized = warn_possibly_uninitialized; - calculate_dominance_info (CDI_POST_DOMINATORS); FOR_EACH_BB (bb) { @@ -1391,16 +1769,14 @@ warn_uninitialized_vars (bool warn_possibly_uninitialized) { struct walk_stmt_info wi; data.stmt = gsi_stmt (gsi); + if (is_gimple_debug (data.stmt)) + continue; memset (&wi, 0, sizeof (wi)); wi.info = &data; walk_gimple_op (gsi_stmt (gsi), warn_uninitialized_var, &wi); } } - /* Post-dominator information can not be reliably updated. Free it - after the use. */ - - free_dominance_info (CDI_POST_DOMINATORS); return 0; } @@ -1413,25 +1789,14 @@ execute_early_warn_uninitialized (void) as possible, thus don't do it here. However, without optimization we need to warn here about "may be uninitialized". */ - warn_uninitialized_vars (/*warn_possibly_uninitialized=*/!optimize); - return 0; -} - -static unsigned int -execute_late_warn_uninitialized (void) -{ - basic_block bb; - gimple_stmt_iterator gsi; + calculate_dominance_info (CDI_POST_DOMINATORS); - /* Re-do the plain uninitialized variable check, as optimization may have - straightened control flow. Do this first so that we don't accidentally - get a "may be" warning when we'd have seen an "is" warning later. */ - warn_uninitialized_vars (/*warn_possibly_uninitialized=*/1); + warn_uninitialized_vars (/*warn_possibly_uninitialized=*/!optimize); - FOR_EACH_BB (bb) - for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi)) - warn_uninitialized_phi (gsi_stmt (gsi)); + /* Post-dominator information can not be reliably updated. Free it + after the use. */ + free_dominance_info (CDI_POST_DOMINATORS); return 0; } @@ -1445,13 +1810,13 @@ struct gimple_opt_pass pass_early_warn_uninitialized = { { GIMPLE_PASS, - NULL, /* name */ + "*early_warn_uninitialized", /* name */ gate_warn_uninitialized, /* gate */ execute_early_warn_uninitialized, /* execute */ NULL, /* sub */ NULL, /* next */ 0, /* static_pass_number */ - TV_NONE, /* tv_id */ + TV_TREE_UNINIT, /* tv_id */ PROP_ssa, /* properties_required */ 0, /* properties_provided */ 0, /* properties_destroyed */ @@ -1460,37 +1825,140 @@ struct gimple_opt_pass pass_early_warn_uninitialized = } }; -struct gimple_opt_pass pass_late_warn_uninitialized = + +/* If necessary, rewrite the base of the reference tree *TP from + a MEM_REF to a plain or converted symbol. */ + +static void +maybe_rewrite_mem_ref_base (tree *tp) { - { - GIMPLE_PASS, - NULL, /* name */ - gate_warn_uninitialized, /* gate */ - execute_late_warn_uninitialized, /* execute */ - NULL, /* sub */ - NULL, /* next */ - 0, /* static_pass_number */ - TV_NONE, /* tv_id */ - PROP_ssa, /* properties_required */ - 0, /* properties_provided */ - 0, /* properties_destroyed */ - 0, /* todo_flags_start */ - 0 /* todo_flags_finish */ - } -}; + tree sym; + + while (handled_component_p (*tp)) + tp = &TREE_OPERAND (*tp, 0); + if (TREE_CODE (*tp) == MEM_REF + && TREE_CODE (TREE_OPERAND (*tp, 0)) == ADDR_EXPR + && integer_zerop (TREE_OPERAND (*tp, 1)) + && (sym = TREE_OPERAND (TREE_OPERAND (*tp, 0), 0)) + && DECL_P (sym) + && !TREE_ADDRESSABLE (sym) + && symbol_marked_for_renaming (sym)) + { + if (!useless_type_conversion_p (TREE_TYPE (*tp), + TREE_TYPE (sym))) + *tp = build1 (VIEW_CONVERT_EXPR, + TREE_TYPE (*tp), sym); + else + *tp = sym; + } +} + +/* For a tree REF return its base if it is the base of a MEM_REF + that cannot be rewritten into SSA form. Otherwise return NULL_TREE. */ + +static tree +non_rewritable_mem_ref_base (tree ref) +{ + tree base = ref; + + /* A plain decl does not need it set. */ + if (DECL_P (ref)) + return NULL_TREE; + + while (handled_component_p (base)) + base = TREE_OPERAND (base, 0); + + /* But watch out for MEM_REFs we cannot lower to a + VIEW_CONVERT_EXPR. */ + if (TREE_CODE (base) == MEM_REF + && TREE_CODE (TREE_OPERAND (base, 0)) == ADDR_EXPR) + { + tree decl = TREE_OPERAND (TREE_OPERAND (base, 0), 0); + if (DECL_P (decl) + && (!integer_zerop (TREE_OPERAND (base, 1)) + || (DECL_SIZE (decl) + != TYPE_SIZE (TREE_TYPE (base))) + || TREE_THIS_VOLATILE (decl) != TREE_THIS_VOLATILE (base))) + return decl; + } + + return NULL_TREE; +} + +/* When possible, clear TREE_ADDRESSABLE bit or set DECL_GIMPLE_REG_P bit and + mark the variable VAR for conversion into SSA. Return true when updating + stmts is required. */ + +static bool +maybe_optimize_var (tree var, bitmap addresses_taken, bitmap not_reg_needs) +{ + bool update_vops = false; + + /* Global Variables, result decls cannot be changed. */ + if (is_global_var (var) + || TREE_CODE (var) == RESULT_DECL + || bitmap_bit_p (addresses_taken, DECL_UID (var))) + return false; + + /* If the variable is not in the list of referenced vars then we + do not need to touch it nor can we rename it. */ + if (!referenced_var_lookup (DECL_UID (var))) + return false; + + if (TREE_ADDRESSABLE (var) + /* Do not change TREE_ADDRESSABLE if we need to preserve var as + a non-register. Otherwise we are confused and forget to + add virtual operands for it. */ + && (!is_gimple_reg_type (TREE_TYPE (var)) + || !bitmap_bit_p (not_reg_needs, DECL_UID (var)))) + { + TREE_ADDRESSABLE (var) = 0; + if (is_gimple_reg (var)) + mark_sym_for_renaming (var); + update_vops = true; + if (dump_file) + { + fprintf (dump_file, "No longer having address taken: "); + print_generic_expr (dump_file, var, 0); + fprintf (dump_file, "\n"); + } + } + + if (!DECL_GIMPLE_REG_P (var) + && !bitmap_bit_p (not_reg_needs, DECL_UID (var)) + && (TREE_CODE (TREE_TYPE (var)) == COMPLEX_TYPE + || TREE_CODE (TREE_TYPE (var)) == VECTOR_TYPE) + && !TREE_THIS_VOLATILE (var) + && (TREE_CODE (var) != VAR_DECL || !DECL_HARD_REGISTER (var))) + { + DECL_GIMPLE_REG_P (var) = 1; + mark_sym_for_renaming (var); + update_vops = true; + if (dump_file) + { + fprintf (dump_file, "Now a gimple register: "); + print_generic_expr (dump_file, var, 0); + fprintf (dump_file, "\n"); + } + } + + return update_vops; +} /* Compute TREE_ADDRESSABLE and DECL_GIMPLE_REG_P for local variables. */ void -execute_update_addresses_taken (bool do_optimize) +execute_update_addresses_taken (void) { - tree var; - referenced_var_iterator rvi; gimple_stmt_iterator gsi; basic_block bb; bitmap addresses_taken = BITMAP_ALLOC (NULL); bitmap not_reg_needs = BITMAP_ALLOC (NULL); bool update_vops = false; + tree var; + unsigned i; + + timevar_push (TV_ADDRESS_TAKEN); /* Collect into ADDRESSES_TAKEN all variables whose address is taken within the function body. */ @@ -1500,6 +1968,7 @@ execute_update_addresses_taken (bool do_optimize) { gimple stmt = gsi_stmt (gsi); enum gimple_code code = gimple_code (stmt); + tree decl; /* Note all addresses taken by the stmt. */ gimple_ior_addresses_taken (addresses_taken, stmt); @@ -1509,20 +1978,87 @@ execute_update_addresses_taken (bool do_optimize) if (code == GIMPLE_ASSIGN || code == GIMPLE_CALL) { tree lhs = gimple_get_lhs (stmt); - - /* We may not rewrite TMR_SYMBOL to SSA. */ - if (lhs && TREE_CODE (lhs) == TARGET_MEM_REF - && TMR_SYMBOL (lhs)) - bitmap_set_bit (not_reg_needs, DECL_UID (TMR_SYMBOL (lhs))); /* A plain decl does not need it set. */ - else if (lhs && handled_component_p (lhs)) - { - var = get_base_address (lhs); - if (DECL_P (var)) - bitmap_set_bit (not_reg_needs, DECL_UID (var)); + if (lhs && !DECL_P (lhs)) + { + tree orig_lhs = lhs; + + while (handled_component_p (lhs)) + lhs = TREE_OPERAND (lhs, 0); + + if (DECL_P (lhs)) + bitmap_set_bit (not_reg_needs, DECL_UID (lhs)); + else if (TREE_CODE (lhs) == MEM_REF + && TREE_CODE (TREE_OPERAND (lhs, 0)) == ADDR_EXPR) + { + decl = TREE_OPERAND (TREE_OPERAND (lhs, 0), 0); + if (DECL_P (decl) + && (!integer_zerop (TREE_OPERAND (lhs, 1)) + || (DECL_SIZE (decl) + != TYPE_SIZE (TREE_TYPE (orig_lhs))) + || (TREE_THIS_VOLATILE (lhs) + != TREE_THIS_VOLATILE (decl)))) + bitmap_set_bit (not_reg_needs, DECL_UID (decl)); + } } } + + if (gimple_assign_single_p (stmt)) + { + tree rhs = gimple_assign_rhs1 (stmt); + if ((decl = non_rewritable_mem_ref_base (rhs))) + bitmap_set_bit (not_reg_needs, DECL_UID (decl)); + } + + else if (code == GIMPLE_CALL) + { + for (i = 0; i < gimple_call_num_args (stmt); ++i) + { + tree arg = gimple_call_arg (stmt, i); + if ((decl = non_rewritable_mem_ref_base (arg))) + bitmap_set_bit (not_reg_needs, DECL_UID (decl)); + } + } + + else if (code == GIMPLE_ASM) + { + for (i = 0; i < gimple_asm_noutputs (stmt); ++i) + { + tree link = gimple_asm_output_op (stmt, i); + tree lhs = TREE_VALUE (link); + + /* A plain decl does not need it set. */ + if (!DECL_P (lhs)) + { + tree orig_lhs = lhs; + + while (handled_component_p (lhs)) + lhs = TREE_OPERAND (lhs, 0); + + if (DECL_P (lhs)) + bitmap_set_bit (not_reg_needs, DECL_UID (lhs)); + else if (TREE_CODE (lhs) == MEM_REF + && TREE_CODE (TREE_OPERAND (lhs, 0)) == ADDR_EXPR) + { + decl = TREE_OPERAND (TREE_OPERAND (lhs, 0), 0); + if (DECL_P (decl) + && (!integer_zerop (TREE_OPERAND (lhs, 1)) + || (TYPE_MAIN_VARIANT (TREE_TYPE (decl)) + != TYPE_MAIN_VARIANT (TREE_TYPE (orig_lhs))) + || (TREE_THIS_VOLATILE (lhs) + != TREE_THIS_VOLATILE (decl)))) + bitmap_set_bit (not_reg_needs, DECL_UID (decl)); + } + } + } + for (i = 0; i < gimple_asm_ninputs (stmt); ++i) + { + tree link = gimple_asm_input_op (stmt, i); + if ((decl = non_rewritable_mem_ref_base (TREE_VALUE (link)))) + bitmap_set_bit (not_reg_needs, DECL_UID (decl)); + } + } } for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi)) @@ -1541,66 +2077,97 @@ execute_update_addresses_taken (bool do_optimize) } } - /* When possible, clear ADDRESSABLE bit or set the REGISTER bit - and mark variable for conversion into SSA. */ - if (optimize && do_optimize) - FOR_EACH_REFERENCED_VAR (var, rvi) - { - /* Global Variables, result decls cannot be changed. */ - if (is_global_var (var) - || TREE_CODE (var) == RESULT_DECL - || bitmap_bit_p (addresses_taken, DECL_UID (var))) - continue; - - if (TREE_ADDRESSABLE (var) - /* Do not change TREE_ADDRESSABLE if we need to preserve var as - a non-register. Otherwise we are confused and forget to - add virtual operands for it. */ - && (!is_gimple_reg_type (TREE_TYPE (var)) - || !bitmap_bit_p (not_reg_needs, DECL_UID (var)))) + /* We cannot iterate over all referenced vars because that can contain + unused vars from BLOCK trees, which causes code generation differences + for -g vs. -g0. */ + for (var = DECL_ARGUMENTS (cfun->decl); var; var = DECL_CHAIN (var)) + update_vops |= maybe_optimize_var (var, addresses_taken, not_reg_needs); + + FOR_EACH_VEC_ELT (tree, cfun->local_decls, i, var) + update_vops |= maybe_optimize_var (var, addresses_taken, not_reg_needs); + + /* Operand caches need to be recomputed for operands referencing the updated + variables. */ + if (update_vops) + { + FOR_EACH_BB (bb) + for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi)) { - TREE_ADDRESSABLE (var) = 0; - if (is_gimple_reg (var)) - mark_sym_for_renaming (var); - update_vops = true; - if (dump_file) + gimple stmt = gsi_stmt (gsi); + + /* Re-write TARGET_MEM_REFs of symbols we want to + rewrite into SSA form. */ + if (gimple_assign_single_p (stmt)) { - fprintf (dump_file, "No longer having address taken "); - print_generic_expr (dump_file, var, 0); - fprintf (dump_file, "\n"); + tree lhs = gimple_assign_lhs (stmt); + tree rhs, *rhsp = gimple_assign_rhs1_ptr (stmt); + tree sym; + + /* We shouldn't have any fancy wrapping of + component-refs on the LHS, but look through + VIEW_CONVERT_EXPRs as that is easy. */ + while (TREE_CODE (lhs) == VIEW_CONVERT_EXPR) + lhs = TREE_OPERAND (lhs, 0); + if (TREE_CODE (lhs) == MEM_REF + && TREE_CODE (TREE_OPERAND (lhs, 0)) == ADDR_EXPR + && integer_zerop (TREE_OPERAND (lhs, 1)) + && (sym = TREE_OPERAND (TREE_OPERAND (lhs, 0), 0)) + && DECL_P (sym) + && !TREE_ADDRESSABLE (sym) + && symbol_marked_for_renaming (sym)) + lhs = sym; + else + lhs = gimple_assign_lhs (stmt); + + /* Rewrite the RHS and make sure the resulting assignment + is validly typed. */ + maybe_rewrite_mem_ref_base (rhsp); + rhs = gimple_assign_rhs1 (stmt); + if (gimple_assign_lhs (stmt) != lhs + && !useless_type_conversion_p (TREE_TYPE (lhs), + TREE_TYPE (rhs))) + rhs = fold_build1 (VIEW_CONVERT_EXPR, + TREE_TYPE (lhs), rhs); + + if (gimple_assign_lhs (stmt) != lhs) + gimple_assign_set_lhs (stmt, lhs); + + if (gimple_assign_rhs1 (stmt) != rhs) + { + gimple_stmt_iterator gsi = gsi_for_stmt (stmt); + gimple_assign_set_rhs_from_tree (&gsi, rhs); + } } - } - if (!DECL_GIMPLE_REG_P (var) - && !bitmap_bit_p (not_reg_needs, DECL_UID (var)) - && (TREE_CODE (TREE_TYPE (var)) == COMPLEX_TYPE - || TREE_CODE (TREE_TYPE (var)) == VECTOR_TYPE) - && !TREE_THIS_VOLATILE (var) - && (TREE_CODE (var) != VAR_DECL || !DECL_HARD_REGISTER (var))) - { - DECL_GIMPLE_REG_P (var) = 1; - mark_sym_for_renaming (var); - update_vops = true; - if (dump_file) + + else if (gimple_code (stmt) == GIMPLE_CALL) { - fprintf (dump_file, "Decl is now a gimple register "); - print_generic_expr (dump_file, var, 0); - fprintf (dump_file, "\n"); + unsigned i; + for (i = 0; i < gimple_call_num_args (stmt); ++i) + { + tree *argp = gimple_call_arg_ptr (stmt, i); + maybe_rewrite_mem_ref_base (argp); + } } - } - } - /* Operand caches needs to be recomputed for operands referencing the updated - variables. */ - if (update_vops) - { - FOR_EACH_BB (bb) - for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi)) - { - gimple stmt = gsi_stmt (gsi); + else if (gimple_code (stmt) == GIMPLE_ASM) + { + unsigned i; + for (i = 0; i < gimple_asm_noutputs (stmt); ++i) + { + tree link = gimple_asm_output_op (stmt, i); + maybe_rewrite_mem_ref_base (&TREE_VALUE (link)); + } + for (i = 0; i < gimple_asm_ninputs (stmt); ++i) + { + tree link = gimple_asm_input_op (stmt, i); + maybe_rewrite_mem_ref_base (&TREE_VALUE (link)); + } + } - if (gimple_references_memory_p (stmt)) - update_stmt (stmt); - } + if (gimple_references_memory_p (stmt) + || is_gimple_debug (stmt)) + update_stmt (stmt); + } /* Update SSA form here, we are called as non-pass as well. */ update_ssa (TODO_update_ssa); @@ -1608,6 +2175,7 @@ execute_update_addresses_taken (bool do_optimize) BITMAP_FREE (not_reg_needs); BITMAP_FREE (addresses_taken); + timevar_pop (TV_ADDRESS_TAKEN); } struct gimple_opt_pass pass_update_address_taken = @@ -1620,7 +2188,7 @@ struct gimple_opt_pass pass_update_address_taken = NULL, /* sub */ NULL, /* next */ 0, /* static_pass_number */ - TV_NONE, /* tv_id */ + TV_ADDRESS_TAKEN, /* tv_id */ PROP_ssa, /* properties_required */ 0, /* properties_provided */ 0, /* properties_destroyed */