CbC/CbC_gcc: gcc/ipa-type-escape.c comparison

comparison gcc/ipa-type-escape.c @ 55:77e2b8dfacca gcc-4.4.5

update it from 4.4.3 to 4.5.0

author	ryoma <e075725@ie.u-ryukyu.ac.jp>
date	Fri, 12 Feb 2010 23:39:51 +0900
parents	a06113de4d67
children	b7f97abdc517

comparison

equal deleted inserted replaced

-:c156f1bd5cd9
+:77e2b8dfacca
 #include "tree-flow.h"
 #include "tree-inline.h"
 #include "tree-pass.h"
 #include "langhooks.h"
 #include "pointer-set.h"
+#include "splay-tree.h"
 #include "ggc.h"
 #include "ipa-utils.h"
 #include "ipa-type-escape.h"
-#include "c-common.h"
 #include "gimple.h"
 #include "cgraph.h"
 #include "output.h"
 #include "flags.h"
 #include "timevar.h"
 /* The following two bit vectors global_types_* correspond to
 previous cases above.  During the analysis phase, a bit is set in
 one of these vectors if an operation of the offending class is
 discovered to happen on the associated type.  */
 static bitmap global_types_exposed_parameter;
 static bitmap global_types_full_escape;
 /* All of the types seen in this compilation unit. */
 static bitmap global_types_seen;
 recursively.  */
 static struct pointer_set_t *visited_stmts;
 static bitmap_obstack ipa_obstack;
 /* Static functions from this file that are used
 before being defined.  */
 static unsigned int look_for_casts (tree);
 static bool is_cast_from_non_pointer (tree, gimple, void *);
 /* Get the name of TYPE or return the string "<UNNAMED>".  */
 static const char*
 get_name_of_type (tree type)
 {
 tree name = TYPE_NAME (type);
 if (!name)
 /* Unnamed type, do what you like here.  */
 return "<UNNAMED>";
 /* It will be a TYPE_DECL in the case of a typedef, otherwise, an
 identifier_node */
 if (TREE_CODE (name) == TYPE_DECL)
 {
 /*  Each DECL has a DECL_NAME field which contains an
 	/* Unnamed type, do what you like here.  */
 	return "<UNNAMED>";
 }
 else if (TREE_CODE (name) == IDENTIFIER_NODE)
 return IDENTIFIER_POINTER (name);
 else
 return "<UNNAMED>";
 }
 struct type_brand_s
 {
 const char* name;
 int seq;
 };
 /* Splay tree comparison function on type_brand_s structures.  */
 static int
 compare_type_brand (splay_tree_key sk1, splay_tree_key sk2)
 {
 struct type_brand_s * k1 = (struct type_brand_s *) sk1;
 struct type_brand_s * k2 = (struct type_brand_s *) sk2;
 int value = strcmp(k1->name, k2->name);
 if (value == 0)
 return k2->seq - k1->seq;
 else
 return value;
 }
 /* All of the "unique_type" code is a hack to get around the sleazy
 implementation used to compile more than file.  Currently gcc does
 case RECORD_TYPE:
 case UNION_TYPE:
 case VECTOR_TYPE:
 case VOID_TYPE:
 return true;
 default:
 return false;
 }
 }
 /* Get the canon type of TYPE.  If SEE_THRU_PTRS is true, remove all
 the POINTER_TOs and if SEE_THRU_ARRAYS is true, remove all of the
 ARRAY_OFs and POINTER_TOs.  */
 static tree
 get_canon_type (tree type, bool see_thru_ptrs, bool see_thru_arrays)
 {
 splay_tree_node result;
 /* Strip the *'s off.  */
 if (!type || !type_to_consider (type))
 return NULL;
 type = TYPE_MAIN_VARIANT (type);
 if (see_thru_arrays)
 while (POINTER_TYPE_P (type) || TREE_CODE (type) == ARRAY_TYPE)
 type = TYPE_MAIN_VARIANT (TREE_TYPE (type));
 else if (see_thru_ptrs)
 while (POINTER_TYPE_P (type))
 	type = TYPE_MAIN_VARIANT (TREE_TYPE (type));
 result = splay_tree_lookup (type_to_canon_type, (splay_tree_key) type);
 if (result == NULL)
 return discover_unique_type (type);
 else return (tree) result->value;
 }
 /* Return 0 if TYPE is a record or union type.  Return a positive
 number if TYPE is a pointer to a record or union.  The number is
 the number of pointer types stripped to get to the record or union
 type.  Return -1 if TYPE is none of the above.  */
 int
 ipa_type_escape_star_count_of_interesting_type (tree type)
 {
 int count = 0;
 /* Strip the *'s off.  */
 if (!type)
 return -1;
 type = TYPE_MAIN_VARIANT (TREE_TYPE (type));
 count++;
 }
 /* We are interested in records, and unions only.  */
 if (TREE_CODE (type) == RECORD_TYPE
 || TREE_CODE (type) == QUAL_UNION_TYPE
 || TREE_CODE (type) == UNION_TYPE)
 return count;
 else
 return -1;
 }
 /* Return 0 if TYPE is a record or union type.  Return a positive
 number if TYPE is a pointer to a record or union.  The number is
 the number of pointer types stripped to get to the record or union
 type.  Return -1 if TYPE is none of the above.  */
 int
 ipa_type_escape_star_count_of_interesting_or_array_type (tree type)
 {
 int count = 0;
 /* Strip the *'s off.  */
 if (!type)
 return -1;
 type = TYPE_MAIN_VARIANT (TREE_TYPE (type));
 count++;
 }
 /* We are interested in records, and unions only.  */
 if (TREE_CODE (type) == RECORD_TYPE
 || TREE_CODE (type) == QUAL_UNION_TYPE
 || TREE_CODE (type) == UNION_TYPE)
 return count;
 else
 return -1;
 }
 /* Return true if the record, or union TYPE passed in escapes this
 compilation unit. Note that all of the pointer-to's are removed
 before testing since these may not be correct.  */
 bool
 ipa_type_escape_type_contained_p (tree type)
 {
 if (!initialized)
 return false;
 return !bitmap_bit_p (global_types_full_escape,
 			get_canon_type_uid (type, true, false));
 }
 /* Return true if a modification to a field of type FIELD_TYPE cannot
 clobber a record of RECORD_TYPE.  */
 bool
 ipa_type_escape_field_does_not_clobber_p (tree record_type, tree field_type)
 {
 splay_tree_node result;
 int uid;
 if (!initialized)
 return false;
 /* Strip off all of the pointer tos on the record type.  Strip the
 same number of pointer tos from the field type.  If the field
 record_type = TYPE_MAIN_VARIANT (record_type);
 field_type = TYPE_MAIN_VARIANT (field_type);
 while (POINTER_TYPE_P (record_type))
 {
 record_type = TYPE_MAIN_VARIANT (TREE_TYPE (record_type));
 if (POINTER_TYPE_P (field_type))
 	field_type = TYPE_MAIN_VARIANT (TREE_TYPE (field_type));
 else
 	/* However, if field_type is a union, this quick test is not
 	   correct since one of the variants of the union may be a
 	   pointer to type and we cannot see across that here.  So we
 	   just strip the remaining pointer tos off the record type
 	   and fall thru to the more precise code.  */
 	if (TREE_CODE (field_type) == QUAL_UNION_TYPE
 	    || TREE_CODE (field_type) == UNION_TYPE)
 	  {
 	    while (POINTER_TYPE_P (record_type))
 	      record_type = TYPE_MAIN_VARIANT (TREE_TYPE (record_type));
 	    break;
 	  }
 	else
 	  return true;
 }
 record_type = get_canon_type (record_type, true, true);
 /* The record type must be contained.  The field type may
 escape.  */
 if (!ipa_type_escape_type_contained_p (record_type))
 return false;
 uid = TYPE_UID (record_type);
 result = splay_tree_lookup (uid_to_addressof_down_map, (splay_tree_key) uid);
 if (result)
 {
 bitmap field_type_map = (bitmap) result->value;
 uid = get_canon_type_uid (field_type, true, true);
 /* If the bit is there, the address was taken. If not, it
 	 wasn't.  */
 {
 bitmap map = NULL;
 int uid;
 type = get_canon_type (type, true, true);
 if (!type)
 return NULL;
 switch (escape_status)
 {
 case EXPOSED_PARAMETER:
 map = global_types_exposed_parameter;
 break;
 case FULL_ESCAPE:
 if (escape_status == FULL_ESCAPE)
 	{
 	  /* Efficiency hack. When things are bad, do not mess around
 	     with this type anymore.  */
 	  bitmap_set_bit (global_types_exposed_parameter, uid);
 	}
 }
 return type;
 }
 /* Add interesting TYPE to the suspect type set. If the set is
 EXPOSED_PARAMETER and the TYPE is a pointer type, the set is
 changed to FULL_ESCAPE.  */
 static void
 mark_interesting_type (tree type, enum escape_t escape_status)
 {
 if (!type) return;
 if (ipa_type_escape_star_count_of_interesting_type (type) >= 0)
 {
 }
 }
 /* Return true if PARENT is supertype of CHILD.  Both types must be
 known to be structures or unions. */
 static bool
 parent_type_p (tree parent, tree child)
 {
 int i;
 tree binfo, base_binfo;
 if (TYPE_BINFO (parent))
 for (binfo = TYPE_BINFO (parent), i = 0;
 	 BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
 {
 	tree binfotype = BINFO_TYPE (base_binfo);
 	if (binfotype == child)
 	  return true;
 	else if (parent_type_p (binfotype, child))
 	  return true;
 }
 if (TREE_CODE (parent) == UNION_TYPE
 || TREE_CODE (parent) == QUAL_UNION_TYPE)
 {
 tree field;
 /* Search all of the variants in the union to see if one of them
 	 is the child.  */
 for (field = TYPE_FIELDS (parent);
 	   field = TREE_CHAIN (field))
 	{
 	  tree field_type;
 	  if (TREE_CODE (field) != FIELD_DECL)
 	    continue;
 	  field_type = TREE_TYPE (field);
 	  if (field_type == child)
 	    return true;
 	}
 /* If we did not find it, recursively ask the variants if one of
 	 their children is the child type.  */
 	   field = TREE_CHAIN (field))
 	{
 	  tree field_type;
 	  if (TREE_CODE (field) != FIELD_DECL)
 	    continue;
 	  field_type = TREE_TYPE (field);
 	  if (TREE_CODE (field_type) == RECORD_TYPE
 	      || TREE_CODE (field_type) == QUAL_UNION_TYPE
 	      || TREE_CODE (field_type) == UNION_TYPE)
 	    if (parent_type_p (field_type, child))
 	      return true;
 	}
 }
 if (TREE_CODE (parent) == RECORD_TYPE)
 {
 tree field;
 for (field = TYPE_FIELDS (parent);
 	   field;
 	   field = TREE_CHAIN (field))
 	{
 	  tree field_type;
 	  if (TREE_CODE (field) != FIELD_DECL)
 	    continue;
 	  field_type = TREE_TYPE (field);
 	  if (field_type == child)
 	    return true;
 	  /* You can only cast to the first field so if it does not
 	     match, quit.  */
 	  if (TREE_CODE (field_type) == RECORD_TYPE
 	      || TREE_CODE (field_type) == QUAL_UNION_TYPE
 	      || TREE_CODE (field_type) == UNION_TYPE)
 	    {
 	      if (parent_type_p (field_type, child))
 		return true;
 	      else
 		break;
 	    }
 	}
 }
 return false;
 }
 /* Return the number of pointer tos for TYPE and return TYPE with all
 of these stripped off.  */
 static int
 count_stars (tree* type_ptr)
 {
 tree type = *type_ptr;
 int i = 0;
 type = TYPE_MAIN_VARIANT (type);
 static enum cast_type
 check_cast_type (tree to_type, tree from_type)
 {
 int to_stars = count_stars (&to_type);
 int from_stars = count_stars (&from_type);
 if (to_stars != from_stars)
 return CT_SIDEWAYS;
 if (to_type == from_type)
 return CT_USELESS;
 if (parent_type_p (to_type, from_type)) return CT_UP;
 if (parent_type_p (from_type, to_type)) return CT_DOWN;
 return CT_SIDEWAYS;
 }
 /* This function returns nonzero if VAR is result of call
 to malloc function.  */
 static bool
 is_malloc_result (tree var)
 {
 gimple def_stmt;
 if (!var)
 return false;
 if (SSA_NAME_IS_DEFAULT_DEF (var))
 return false;
 def_stmt = SSA_NAME_DEF_STMT (var);
 if (!is_gimple_call (def_stmt))
 return false;
 if (var != gimple_call_lhs (def_stmt))
 return false;
 }
 /* Check a cast FROM this variable, TO_TYPE.  Mark the escaping types
 if appropriate. Returns cast_type as detected.  */
 static enum cast_type
 check_cast (tree to_type, tree from)
 {
 tree from_type = get_canon_type (TREE_TYPE (from), false, false);
 bool to_interesting_type, from_interesting_type;
 enum cast_type cast = CT_NO_CAST;
 to_type = get_canon_type (to_type, false, false);
 if (!from_type || !to_type || from_type == to_type)
 return cast;
 to_interesting_type =
 ipa_type_escape_star_count_of_interesting_type (to_type) >= 0;
 from_interesting_type =
 ipa_type_escape_star_count_of_interesting_type (from_type) >= 0;
 if (to_interesting_type)
 if (from_interesting_type)
 {
 	/* Both types are interesting. This can be one of four types
 	   of cast: useless, up, down, or sideways.  We do not care
 	   about up or useless.  Sideways casts are always bad and
 	   both sides get marked as escaping.  Downcasts are not
 	   interesting here because if type is marked as escaping, all
 	   of its subtypes escape.  */
 	cast = check_cast_type (to_type, from_type);
 	switch (cast)
 	  {
 	  case CT_UP:
 	  case CT_USELESS:
 	  case CT_DOWN:
 	    break;
 	  }
 }
 else
 {
 	/* This code excludes two cases from marking as escaped:
 	1. if this is a cast of index of array of structures/unions
 	that happens before accessing array element, we should not
 	mark it as escaped.
 	2. if this is a cast from the local that is a result from a
 	call to malloc, do not mark the cast as bad.
 	*/
 	if (POINTER_TYPE_P (to_type) && !POINTER_TYPE_P (from_type))
 	  cast = CT_FROM_NON_P;
 	else if (TREE_CODE (from) == SSA_NAME
 		 && is_malloc_result (from))
 	  cast = CT_FROM_MALLOC;
 	else
 	  {
 	    cast = CT_FROM_P_BAD;
 if (!cast)
 cast = CT_NO_CAST;
 return cast;
 }
 typedef struct cast
 {
 int type;
 gimple stmt;
 } cast_t;
 /* This function is a callback for walk_use_def_chains function called
 from is_array_access_through_pointer_and_index.  */
 static bool
 is_cast_from_non_pointer (tree var, gimple def_stmt, void *data)
 {
 if (!def_stmt || !var)
 return false;
 if (gimple_code (def_stmt) == GIMPLE_PHI)
 return false;
 if (SSA_NAME_IS_DEFAULT_DEF (var))
 return false;
 if (is_gimple_assign (def_stmt))
 {
 use_operand_p use_p;
 ssa_op_iter iter;
 unsigned int cast = look_for_casts_stmt (def_stmt);
 /* Check that only one cast happened, and it's of non-pointer
 	 type.  */
 if ((cast & CT_FROM_NON_P) == (CT_FROM_NON_P)
 	  && (cast & ~(CT_FROM_NON_P)) == 0)
 	{
 	  ((cast_t *)data)->stmt = def_stmt;
 	  ((cast_t *)data)->type++;
 	    {
 	      walk_use_def_chains (USE_FROM_PTR (use_p),
 				   is_cast_from_non_pointer, data, false);
 	      if (((cast_t*)data)->type == -1)
 		break;
 	    }
 	}
 	/* The cast is harmful.  */
 	else
 	  ((cast_t *)data)->type = -1;
 }
 if (((cast_t*)data)->type == -1)
 return true;
 return false;
 }
 /* When array element a_p[i] is accessed through the pointer a_p
 and index i, it's translated into the following sequence
 in gimple:
 i.1_5 = (unsigned int) i_1;
 D.1605_6 = i.1_5 * 16;
 D.1606_7 = (struct str_t *) D.1605_6;
 a_p.2_8 = a_p;
 D.1608_9 = D.1606_7 + a_p.2_8;
 OP0 and OP1 are of the same pointer types and stand for
 D.1606_7 and a_p.2_8 or vise versa.
 This function checks that:
 1. one of OP0 and OP1 (D.1606_7) has passed only one cast from
 non-pointer type (D.1606_7 = (struct str_t *) D.1605_6;).
 2. one of OP0 and OP1 which has passed the cast from
 non-pointer type (D.1606_7), is actually generated by multiplication of
 index by size of type to which both OP0 and OP1 point to
 (in this case D.1605_6 = i.1_5 * 16; ).
 3. an address of def of the var to which was made cast (D.1605_6)
 was not taken.(How can it happen?)
 The following items are checked implicitly by the end of algorithm:
 4. one of OP0 and OP1 (a_p.2_8) have never been cast
 (because if it was cast to pointer type, its type, that is also
 the type of OP0 and OP1, will be marked as escaped during
 analysis of casting stmt (when check_cast() is called
 from scan_for_refs for this stmt)).
 5. defs of OP0 and OP1 are not passed into externally visible function
 (because if they are passed then their type, that is also the type of OP0
 and OP1, will be marked and escaped during check_call function called from
 scan_for_refs with call stmt).
 In total, 1-5 guaranty that it's an access to array by pointer and index.
 */
 bool
 is_array_access_through_pointer_and_index (enum tree_code code, tree op0,
 					   tree op1, tree *base, tree *offset,
 					   gimple *offset_cast_stmt)
 {
 tree before_cast;
 gimple before_cast_def_stmt;
 visited_stmts = pointer_set_create ();
 walk_use_def_chains (op0, is_cast_from_non_pointer,(void *)(&op0_cast),
 			   false);
 pointer_set_destroy (visited_stmts);
 visited_stmts = pointer_set_create ();
 walk_use_def_chains (op1, is_cast_from_non_pointer,(void *)(&op1_cast),
 			   false);
 pointer_set_destroy (visited_stmts);
 if (op0_cast.type == 1 && op1_cast.type == 0)
 	  *offset_cast_stmt = op0_cast.stmt;
 	}
 else if (op0_cast.type == 0 && op1_cast.type == 1)
 	{
 	  *base = op0;
 	  *offset = op1;
 	  *offset_cast_stmt = op1_cast.stmt;
 	}
 else
 	return false;
 }
 /* Check 2.
 offset_cast_stmt is of the form:
 D.1606_7 = (struct str_t *) D.1605_6;  */
 if (*offset_cast_stmt)
 {
 before_cast = SINGLE_SSA_TREE_OPERAND (*offset_cast_stmt, SSA_OP_USE);
 if (!before_cast)
 	return false;
 if (SSA_NAME_IS_DEFAULT_DEF (before_cast))
 	return false;
 before_cast_def_stmt = SSA_NAME_DEF_STMT (before_cast);
 if (!before_cast_def_stmt)
 	return false;
 }
 else
 before_cast_def_stmt = SSA_NAME_DEF_STMT (*offset);
 /* before_cast_def_stmt should be of the form:
 D.1605_6 = i.1_5 * 16; */
 if (is_gimple_assign (before_cast_def_stmt))
 {
 /* We expect temporary here.  */
 if (!is_gimple_reg (gimple_assign_lhs (before_cast_def_stmt)))
 	return false;
 if (gimple_assign_rhs_code (before_cast_def_stmt) == MULT_EXPR)
 	{
 	  tree arg0 = gimple_assign_rhs1 (before_cast_def_stmt);
 	  tree arg1 = gimple_assign_rhs2 (before_cast_def_stmt);
 	  tree unit_size =
 	    TYPE_SIZE_UNIT (TREE_TYPE (TYPE_MAIN_VARIANT (TREE_TYPE (op0))));
 	  if (!(CONSTANT_CLASS_P (arg0)
 	      && simple_cst_equal (arg0, unit_size))
 	      && !(CONSTANT_CLASS_P (arg1)
 	      && simple_cst_equal (arg1, unit_size)))
 	    return false;
 	}
 else
 	return false;
 }
 else
 }
 /* Register the parameter and return types of function FN.  The type
 ESCAPES if the function is visible outside of the compilation
 unit.  */
 static void
 check_function_parameter_and_return_types (tree fn, bool escapes)
 {
 tree arg;
 if (TYPE_ARG_TYPES (TREE_TYPE (fn)))
 {
 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
 	   arg && TREE_VALUE (arg) != void_type_node;
 	   arg = TREE_CHAIN (arg))
 	}
 }
 if (escapes)
 {
 tree type = get_canon_type (TREE_TYPE (TREE_TYPE (fn)), false, false);
 mark_interesting_type (type, EXPOSED_PARAMETER);
 }
 }
 /* Return true if the variable T is the right kind of static variable to
 perform compilation unit scope escape analysis.  */
 return;
 }
 /* Do not want to do anything with volatile except mark any
 function that uses one to be not const or pure.  */
 if (TREE_THIS_VOLATILE (t))
 return;
 /* Do not care about a local automatic that is not static.  */
 if (!TREE_STATIC (t) && !DECL_EXTERNAL (t))
 return;
 {
 /* If the front end set the variable to be READONLY and
 	 constant, we can allow this variable in pure or const
 	 functions but the scope is too large for our analysis to set
 	 these bits ourselves.  */
 if (TREE_READONLY (t)
 	  && DECL_INITIAL (t)
 	  && is_gimple_min_invariant (DECL_INITIAL (t)))
 	; /* Read of a constant, do not change the function state.  */
 else
 	{
 	  /* The type escapes for all public and externs. */
 	  mark_interesting_type (type, FULL_ESCAPE);
 	}
 }
 escaping.  */
 if (TREE_CODE (t) == FUNCTION_DECL)
 check_function_parameter_and_return_types (t, true);
 else if (TREE_CODE (t) == VAR_DECL)
 has_proper_scope_for_analysis (t);
 }
 /* Examine tree T for references.   */
 static void
 check_tree (tree t)
 {
-if ((TREE_CODE (t) == EXC_PTR_EXPR) || (TREE_CODE (t) == FILTER_EXPR))
-return;
 /* We want to catch here also REALPART_EXPR and IMAGEPART_EXPR,
 but they already included in handled_component_p.  */
 while (handled_component_p (t))
 {
 if (TREE_CODE (t) == ARRAY_REF)
 mark_interesting_addressof (tree to_type, tree from_type)
 {
 int from_uid;
 int to_uid;
 bitmap type_map;
 splay_tree_node result;
 from_type = get_canon_type (from_type, false, false);
 to_type = get_canon_type (to_type, false, false);
 if (!from_type || !to_type)
 return;
 from_uid = TYPE_UID (from_type);
 to_uid = TYPE_UID (to_type);
 gcc_assert (ipa_type_escape_star_count_of_interesting_type (from_type) == 0);
 /* Process the Y into X map pointer.  */
 result = splay_tree_lookup (uid_to_addressof_down_map,
 			      (splay_tree_key) from_uid);
 if (result)
 type_map = (bitmap) result->value;
 else
 {
 type_map = BITMAP_ALLOC (&ipa_obstack);
 splay_tree_insert (uid_to_addressof_down_map,
 			 from_uid,
 			 (splay_tree_value)type_map);
 }
 bitmap_set_bit (type_map, TYPE_UID (to_type));
 /* Process the X into Y reverse map pointer.  */
 result =
 splay_tree_lookup (uid_to_addressof_up_map, (splay_tree_key) to_uid);
 if (result)
 type_map = (bitmap) result->value;
 else
 {
 type_map = BITMAP_ALLOC (&ipa_obstack);
 splay_tree_insert (uid_to_addressof_up_map,
 			 to_uid,
 			 (splay_tree_value)type_map);
 }
 bitmap_set_bit (type_map, TYPE_UID (from_type));
 }
 /* Scan tree T to see if there are any addresses taken in within T.  */
 static void
 look_for_address_of (tree t)
 {
 if (TREE_CODE (t) == ADDR_EXPR)
 {
 tree x = get_base_var (t);
 tree cref = TREE_OPERAND (t, 0);
 /* If we have an expression of the form "&a.b.c.d", mark a.b,
 	 b.c and c.d. as having its address taken.  */
 tree fielddecl = NULL_TREE;
 while (cref!= x)
 	{
 	  if (TREE_CODE (cref) == COMPONENT_REF)
 	    {
 	      fielddecl =  TREE_OPERAND (cref, 1);
 	      mark_interesting_addressof (TREE_TYPE (fielddecl),
 					  DECL_FIELD_CONTEXT (fielddecl));
 	    }
 	  else if (TREE_CODE (cref) == ARRAY_REF)
 	    get_canon_type (TREE_TYPE (cref), false, false);
 	  cref = TREE_OPERAND (cref, 0);
 	}
 if (TREE_CODE (x) == VAR_DECL)
 	has_proper_scope_for_analysis (x);
 }
 }
 /* Scan tree T to see if there are any casts within it.  */
 static unsigned int
 look_for_casts (tree t)
 {
 unsigned int cast = 0;
 if (is_gimple_cast (t) || TREE_CODE (t) == VIEW_CONVERT_EXPR)
 {
 tree castfromvar = TREE_OPERAND (t, 0);
 cast = cast | check_cast (TREE_TYPE (t), castfromvar);
 }
 else
 while (handled_component_p (t))
 {
 	t = TREE_OPERAND (t, 0);
 	if (TREE_CODE (t) == VIEW_CONVERT_EXPR)
 	  {
 }
 if (!cast)
 cast = CT_NO_CAST;
 return cast;
 }
 /* Check to see if T is a read or address of operation on a static var
 we are interested in analyzing.  */
 static void
 for (i = 0; i < gimple_asm_noutputs (stmt); i++)
 check_lhs_var (gimple_asm_output_op (stmt, i));
 for (i = 0; i < gimple_asm_ninputs (stmt); i++)
 check_rhs_var (gimple_asm_input_op (stmt, i));
 /* There is no code here to check for asm memory clobbers.  The
 casual maintainer might think that such code would be necessary,
 but that appears to be wrong.  In other parts of the compiler,
 the asm memory clobbers are assumed to only clobber variables
 that are addressable.  All types with addressable instances are
 enum availability avail = AVAIL_NOT_AVAILABLE;
 size_t i;
 for (i = 0; i < gimple_call_num_args (call); i++)
 check_rhs_var (gimple_call_arg (call, i));
 if (callee_t)
 {
 tree arg_type;
 tree last_arg_type = NULL;
 callee = cgraph_node(callee_t);
 avail = cgraph_function_body_availability (callee);
 /* Check that there are no implicit casts in the passing of
 	 parameters.  */
 if (TYPE_ARG_TYPES (TREE_TYPE (callee_t)))
 	{
 	  for (arg_type = TYPE_ARG_TYPES (TREE_TYPE (callee_t)), i = 0;
 	      if (operand)
 		{
 		  last_arg_type = TREE_VALUE(arg_type);
 		  check_cast (last_arg_type, operand);
 		}
 	      else
 		/* The code reaches here for some unfortunate
 		   builtin functions that do not have a list of
 		   argument types.  */
 		break;
 	    }
 	}
 else
 	{
 	  /* FIXME - According to Geoff Keating, we should never
 	     have to do this; the front ends should always process
 	     the arg list from the TYPE_ARG_LIST. */
 	  for (arg_type = DECL_ARGUMENTS (callee_t), i = 0;
 	       arg_type;
 	      tree operand = gimple_call_arg (call, i);
 	      if (operand)
 		{
 		  last_arg_type = TREE_TYPE (arg_type);
 		  check_cast (last_arg_type, operand);
 		}
 	      else
 		/* The code reaches here for some unfortunate
 		   builtin functions that do not have a list of
 		   argument types.  */
 		break;
 	    }
 	}
 /* In the case where we have a var_args function, we need to
 	 check the remaining parameters against the last argument.  */
 arg_type = last_arg_type;
 for ( ; i < gimple_call_num_args (call); i++)
 	{
 	  tree operand = gimple_call_arg (call, i);
 	  if (arg_type)
 	    check_cast (arg_type, operand);
 	  else
 	    {
 	      /* The code reaches here for some unfortunate
 		 builtin functions that do not have a list of
 		 argument types.  Most of these functions have
 		 been marked as having their parameters not
 	{
 	  tree operand = gimple_call_arg (call, i);
 	  tree type = get_canon_type (TREE_TYPE (operand), false, false);
 	  mark_interesting_type (type, EXPOSED_PARAMETER);
 	}
 if (callee_t)
 	{
 	  tree type =
 	    get_canon_type (TREE_TYPE (TREE_TYPE (callee_t)), false, false);
 	  mark_interesting_type (type, EXPOSED_PARAMETER);
 	}
 }
 }
 /* CODE is the operation on OP0 and OP1.  OP0 is the operand that we
 *know* is a pointer type.  OP1 may be a pointer type.  */
 static bool
 okay_pointer_operation (enum tree_code code, tree op0, tree op1)
 {
 tree op0type = TYPE_MAIN_VARIANT (TREE_TYPE (op0));
 switch (code)
 {
 	tree base, offset;
 	gimple offset_cast_stmt;
 	if (POINTER_TYPE_P (op0type)
 	    && TREE_CODE (op0) == SSA_NAME
 	    && TREE_CODE (op1) == SSA_NAME
 	    && is_array_access_through_pointer_and_index (code, op0, op1,
 							  &base,
 							  &offset,
 							  &offset_cast_stmt))
 	  return true;
 	else
 	  {
 	    tree size_of_op0_points_to = TYPE_SIZE_UNIT (TREE_TYPE (op0type));
 	    if (CONSTANT_CLASS_P (op1)
 		&& size_of_op0_points_to
 		&& multiple_of_p (TREE_TYPE (size_of_op0_points_to),
 				  op1, size_of_op0_points_to))
 	      return true;
 	    if (CONSTANT_CLASS_P (op0)
 		&& size_of_op0_points_to
 		&& multiple_of_p (TREE_TYPE (size_of_op0_points_to),
 				  op0, size_of_op0_points_to))
 	      return true;
 	  }
 }
 break;
 default:
 return false;
 /* For the purposes of figuring out what the cast affects */
 /* Next check the operands on the rhs to see if they are ok. */
 switch (TREE_CODE_CLASS (gimple_assign_rhs_code (t)))
 {
 case tcc_binary:
 {
 	tree op0 = gimple_assign_rhs1 (t);
 	tree type0 = get_canon_type (TREE_TYPE (op0), false, false);
 	tree op1 = gimple_assign_rhs2 (t);
 	tree type1 = get_canon_type (TREE_TYPE (op1), false, false);
 interesting.  */
 static void
 scan_for_refs (gimple t)
 {
 switch (gimple_code (t))
 {
 case GIMPLE_ASSIGN:
 check_assign (t);
 break;
 case GIMPLE_CALL:
 /* If this is a call to malloc, squirrel away the result so we
 	 do mark the resulting cast as being bad.  */
 check_call (t);
 break;
 case GIMPLE_ASM:
 check_asm (t);
 break;
 default:
 break;
 }
 return;
 }
 /* The init routine for analyzing global static variable usage.  See
 comments at top for description.  */
 static void
 ipa_init (void)
 {
 bitmap_obstack_initialize (&ipa_obstack);
 global_types_exposed_parameter = BITMAP_ALLOC (&ipa_obstack);
 global_types_full_escape = BITMAP_ALLOC (&ipa_obstack);
 global_types_seen = BITMAP_ALLOC (&ipa_obstack);
 if any of them contain addressof operations.  Note that some of
 these variables may not even be referenced in the code in this
 compilation unit but their right hand sides may contain references
 to variables defined within this unit.  */
 static void
 analyze_variable (struct varpool_node *vnode)
 {
 tree global = vnode->decl;
 tree type = get_canon_type (TREE_TYPE (global), false, false);
 static void
 analyze_function (struct cgraph_node *fn)
 {
 tree decl = fn->decl;
 check_function_parameter_and_return_types (decl,
 					     fn->local.externally_visible);
 if (dump_file)
 fprintf (dump_file, "\n local analysis of %s", cgraph_node_name (fn));
 {
 struct function *this_cfun = DECL_STRUCT_FUNCTION (decl);
 basic_block this_block;
 FOR_EACH_BB_FN (this_block, this_cfun)
 for (step = DECL_STRUCT_FUNCTION (decl)->local_decls;
 	   step;
 	   step = TREE_CHAIN (step))
 	{
 	  tree var = TREE_VALUE (step);
 	  if (TREE_CODE (var) == VAR_DECL
 	      && DECL_INITIAL (var)
 	      && !TREE_STATIC (var))
 	    check_tree (DECL_INITIAL (var));
 	  get_canon_type (TREE_TYPE (var), false, false);
 	}
 /* Convert a type_UID into a type.  */
 static tree
 type_for_uid (int uid)
 {
 splay_tree_node result =
 splay_tree_lookup (uid_to_canon_type, (splay_tree_key) uid);
 if (result)
 return (tree) result->value;
 else return NULL;
 }
 /* Return a bitmap with the subtypes of the type for UID.  If it
 does not exist, return either NULL or a new bitmap depending on the
 value of CREATE.  */
 static bitmap
 subtype_map_for_uid (int uid, bool create)
 {
 splay_tree_node result = splay_tree_lookup (uid_to_subtype_map,
 			      (splay_tree_key) uid);
 if (result)
 return (bitmap) result->value;
 else if (create)
 {
 bitmap subtype_map = BITMAP_ALLOC (&ipa_obstack);
 splay_tree_insert (uid_to_subtype_map,
 			 uid,
 			 (splay_tree_value)subtype_map);
 return subtype_map;
 }
 else return NULL;
 }
 return;
 bitmap_set_bit (been_there_done_that, uid);
 /* If we are doing a language with a type hierarchy, mark all of
 the superclasses.  */
 if (TYPE_BINFO (type))
 for (binfo = TYPE_BINFO (type), i = 0;
 	 BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
 {
 	tree binfo_type = BINFO_TYPE (base_binfo);
 	bitmap subtype_map = subtype_map_for_uid
 	  (TYPE_UID (TYPE_MAIN_VARIANT (binfo_type)), true);
 	bitmap_set_bit (subtype_map, uid);
 	close_type_seen (get_canon_type (binfo_type, true, true));
 }
 /* If the field is a struct or union type, mark all of the
 subfields.  */
 for (field = TYPE_FIELDS (type);
 field;
 field = TREE_CHAIN (field))
 }
 /* Take a TYPE that has been passed by value to an external function
 and mark all of the fields that have pointer types as escaping. For
 any of the non pointer types that are structures or unions,
 recurse.  TYPE is never a pointer type.  */
 static void
 close_type_exposed_parameter (tree type)
 {
 tree field;
 field_type = get_canon_type (TREE_TYPE (field), false, false);
 mark_interesting_type (field_type, EXPOSED_PARAMETER);
 /* Only recurse for non pointer types of structures and unions.  */
 if (ipa_type_escape_star_count_of_interesting_type (field_type) == 0)
 	close_type_exposed_parameter (field_type);
 }
 }
 /* The next function handles the case where a type fully escapes.
 This means that not only does the type itself escape,
 a) the type of every field recursively escapes
 b) the type of every subtype escapes as well as the super as well
 as all of the pointer to types for each field.
 Note that pointer to types are not marked as escaping.  If the
 pointed to type escapes, the pointer to type also escapes.
 Take a TYPE that has had the address taken for an instance of it
 and mark all of the types for its fields as having their addresses
 taken. */
 static void
 close_type_full_escape (tree type)
 {
 tree field;
 unsigned int i;
 int uid;
 tree binfo, base_binfo;
 bitmap_iterator bi;
 bitmap subtype_map;
 splay_tree_node address_result;
 /* Strip off any pointer or array types.  */
 type = get_canon_type (type, true, true);
 if (!type)
 return;
 subtype_map = subtype_map_for_uid (uid, false);
 /* If we are doing a language with a type hierarchy, mark all of
 the superclasses.  */
 if (TYPE_BINFO (type))
 for (binfo = TYPE_BINFO (type), i = 0;
 	 BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
 {
 	tree binfotype = BINFO_TYPE (base_binfo);
 	binfotype = mark_type (binfotype, FULL_ESCAPE);
 	close_type_full_escape (binfotype);
 }
 /* Mark as escaped any types that have been down casted to
 this type. */
 if (subtype_map)
 EXECUTE_IF_SET_IN_BITMAP (subtype_map, 0, i, bi)
 {
 	tree subtype = type_for_uid (i);
 	subtype = mark_type (subtype, FULL_ESCAPE);
 	close_type_full_escape (subtype);
 }
 /* If the field is a struct or union type, mark all of the
 	}
 }
 /* For all of the types A that contain this type B and were part of
 an expression like "&...A.B...", mark the A's as escaping.  */
 address_result = splay_tree_lookup (uid_to_addressof_up_map,
 				      (splay_tree_key) uid);
 if (address_result)
 {
 bitmap containing_classes = (bitmap) address_result->value;
 EXECUTE_IF_SET_IN_BITMAP (containing_classes, 0, i, bi)
 }
 }
 /* Transitively close the addressof bitmap for the type with UID.
 This means that if we had a.b and b.c, a would have both b and c in
 its maps.  */
 static bitmap
 close_addressof_down (int uid)
 {
 bitmap_iterator bi;
 splay_tree_node result =
 splay_tree_lookup (uid_to_addressof_down_map, (splay_tree_key) uid);
 bitmap map = NULL;
 bitmap new_map;
 unsigned int i;
 if (result)
 map = (bitmap) result->value;
 else
 return NULL;
 if (bitmap_bit_p (been_there_done_that, uid))
 return map;
 bitmap_set_bit (been_there_done_that, uid);
 EXECUTE_IF_SET_IN_BITMAP (map, 0, i, bi)
 {
 bitmap submap = close_addressof_down (i);
 bitmap_set_bit (new_map, i);
 if (submap)
 	bitmap_ior_into (new_map, submap);
 }
 result->value = (splay_tree_value) new_map;
 BITMAP_FREE (map);
 return new_map;
 }
 /* Process all of the functions next.
 We do not want to process any of the clones so we check that this
 is a master clone.  However, we do need to process any
 AVAIL_OVERWRITABLE functions (these are never clones) because
 they may cause a type variable to escape.
 */
 for (node = cgraph_nodes; node; node = node->next)
-if (node->analyzed
+if (node->analyzed)
-	&& (cgraph_is_master_clone (node)
-	    || (cgraph_function_body_availability (node) == AVAIL_OVERWRITABLE)))
 analyze_function (node);
 pointer_set_destroy (visited_nodes);
 visited_nodes = NULL;
 /* Before this pass, the uid_to_addressof_down_map for type X
 contained an entry for Y if there had been an operation of the
 form &X.Y.  This step adds all of the fields contained within Y
 (recursively) to X's map.  */
 result = splay_tree_min (uid_to_addressof_down_map);
 while (result)
 {
 int uid = result->key;
 /* Close the addressof map, i.e. copy all of the transitive
 result = splay_tree_min (all_canon_types);
 while (result)
 {
 tree type = (tree) result->value;
 tree key = (tree) result->key;
 if (POINTER_TYPE_P (type)
 	  || TREE_CODE (type) == ARRAY_TYPE)
 	{
 	  splay_tree_remove (all_canon_types, (splay_tree_key) result->key);
 	  splay_tree_remove (type_to_canon_type, (splay_tree_key) type);
 	  splay_tree_remove (uid_to_canon_type, (splay_tree_key) TYPE_UID (type));
 	}
 result = splay_tree_successor (all_canon_types, (splay_tree_key) key);
 }
 if (dump_file)
 {
 EXECUTE_IF_SET_IN_BITMAP (global_types_seen, 0, i, bi)
 	{
 	  /* The pointer types are in the global_types_full_escape
 	     bitmap but not in the backwards map.  They also contain
 	     no useful information since they are not marked.  */
 	  tree type = type_for_uid (i);
 	  fprintf(dump_file, "type %d ", i);
 	  print_generic_expr (dump_file, type, 0);
 	  if (bitmap_bit_p (global_types_full_escape, i))
 	    fprintf(dump_file, " escaped\n");
 	  else
 	    fprintf(dump_file, " contained\n");
 	}
 }
 /* Get rid of uid_to_addressof_up_map and its bitmaps.  */

Mercurial > hg > CbC > CbC_gcc

comparison gcc/ipa-type-escape.c @ 55:77e2b8dfacca gcc-4.4.5