/* Callgraph based analysis of static variables.
- Copyright (C) 2004, 2005, 2007 Free Software Foundation, Inc.
+ Copyright (C) 2004, 2005, 2007, 2008, 2009, 2010
+ Free Software Foundation, Inc.
Contributed by Kenneth Zadeck <zadeck@naturalbridge.com>
This file is part of GCC.
<http://www.gnu.org/licenses/>. */
/* This file gathers information about how variables whose scope is
- confined to the compilation unit are used.
+ confined to the compilation unit are used.
- There are two categories of information produced by this pass:
-
- 1) The addressable (TREE_ADDRESSABLE) bit and readonly
- (TREE_READONLY) bit associated with these variables is properly set
- based on scanning all of the code withing the compilation unit.
-
- 2) The transitive call site specific clobber effects are computed
+ The transitive call site specific clobber effects are computed
for the variables whose scope is contained within this compilation
unit.
side effects of each call. In later parts of the compiler, these
local and global sets are examined to make the call clobbering less
traumatic, promote some statics to registers, and improve aliasing
- information.
-
- Currently must be run after inlining decisions have been made since
- otherwise, the local sets will not contain information that is
- consistent with post inlined state. The global sets are not prone
- to this problem since they are by definition transitive.
-*/
+ information. */
#include "config.h"
#include "system.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-reference.h"
-#include "c-common.h"
-#include "tree-gimple.h"
+#include "gimple.h"
#include "cgraph.h"
#include "output.h"
#include "flags.h"
#include "timevar.h"
#include "diagnostic.h"
#include "langhooks.h"
+#include "data-streamer.h"
+#include "lto-streamer.h"
-/* This splay tree contains all of the static variables that are
- being considered by the compilation level alias analysis. For
- module_at_a_time compilation, this is the set of static but not
- public variables. Any variables that either have their address
- taken or participate in otherwise unsavory operations are deleted
- from this list. */
-static GTY((param1_is(int), param2_is(tree)))
- splay_tree reference_vars_to_consider;
-
-/* This bitmap is used to knock out the module static variables whose
- addresses have been taken and passed around. */
-static bitmap module_statics_escape;
-
-/* This bitmap is used to knock out the module static variables that
- are not readonly. */
-static bitmap module_statics_written;
+static void remove_node_data (struct cgraph_node *node,
+ void *data ATTRIBUTE_UNUSED);
+static void duplicate_node_data (struct cgraph_node *src,
+ struct cgraph_node *dst,
+ void *data ATTRIBUTE_UNUSED);
-/* A bit is set for every module static we are considering. This is
- ored into the local info when asm code is found that clobbers all
- memory. */
-static bitmap all_module_statics;
+/* The static variables defined within the compilation unit that are
+ loaded or stored directly by function that owns this structure. */
-static struct pointer_set_t *visited_nodes;
+struct ipa_reference_local_vars_info_d
+{
+ bitmap statics_read;
+ bitmap statics_written;
+};
-static bitmap_obstack ipa_obstack;
+/* Statics that are read and written by some set of functions. The
+ local ones are based on the loads and stores local to the function.
+ The global ones are based on the local info as well as the
+ transitive closure of the functions that are called. */
-enum initialization_status_t
+struct ipa_reference_global_vars_info_d
{
- UNINITIALIZED,
- RUNNING,
- FINISHED
+ bitmap statics_read;
+ bitmap statics_written;
};
-tree memory_identifier_string;
+/* Information we save about every function after ipa-reference is completed. */
-/* Return the ipa_reference_vars structure starting from the cgraph NODE. */
-static inline ipa_reference_vars_info_t
-get_reference_vars_info_from_cgraph (struct cgraph_node * node)
+struct ipa_reference_optimization_summary_d
{
- return get_function_ann (node->decl)->reference_vars_info;
-}
+ bitmap statics_not_read;
+ bitmap statics_not_written;
+};
-/* Get a bitmap that contains all of the locally referenced static
- variables for function FN. */
-static ipa_reference_local_vars_info_t
-get_local_reference_vars_info (tree fn)
+typedef struct ipa_reference_local_vars_info_d *ipa_reference_local_vars_info_t;
+typedef struct ipa_reference_global_vars_info_d *ipa_reference_global_vars_info_t;
+typedef struct ipa_reference_optimization_summary_d *ipa_reference_optimization_summary_t;
+
+struct ipa_reference_vars_info_d
{
- ipa_reference_vars_info_t info = get_function_ann (fn)->reference_vars_info;
+ struct ipa_reference_local_vars_info_d local;
+ struct ipa_reference_global_vars_info_d global;
+};
- if (info)
- return info->local;
- else
- /* This phase was not run. */
- return NULL;
-}
+typedef struct ipa_reference_vars_info_d *ipa_reference_vars_info_t;
-/* Get a bitmap that contains all of the globally referenced static
- variables for function FN. */
-
-static ipa_reference_global_vars_info_t
-get_global_reference_vars_info (tree fn)
-{
- ipa_reference_vars_info_t info = get_function_ann (fn)->reference_vars_info;
+/* This splay tree contains all of the static variables that are
+ being considered by the compilation level alias analysis. */
+static splay_tree reference_vars_to_consider;
- if (info)
- return info->global;
- else
- /* This phase was not run. */
- return NULL;
-}
+/* A bit is set for every module static we are considering. This is
+ ored into the local info when asm code is found that clobbers all
+ memory. */
+static bitmap all_module_statics;
-/* Return a bitmap indexed by VAR_DECL uid for the static variables
- that may be read locally by the execution of the function fn.
- Returns NULL if no data is available. */
+/* Obstack holding bitmaps of local analysis (live from analysis to
+ propagation) */
+static bitmap_obstack local_info_obstack;
+/* Obstack holding global analysis live forever. */
+static bitmap_obstack optimization_summary_obstack;
-bitmap
-ipa_reference_get_read_local (tree fn)
-{
- ipa_reference_local_vars_info_t l = get_local_reference_vars_info (fn);
- if (l)
- return l->statics_read;
- else
- return NULL;
-}
+/* Holders of ipa cgraph hooks: */
+static struct cgraph_2node_hook_list *node_duplication_hook_holder;
+static struct cgraph_node_hook_list *node_removal_hook_holder;
-/* Return a bitmap indexed by VAR_DECL uid for the static variables
- that may be written locally by the execution of the function fn.
- Returns NULL if no data is available. */
+/* Vector where the reference var infos are actually stored. */
+DEF_VEC_P (ipa_reference_vars_info_t);
+DEF_VEC_ALLOC_P (ipa_reference_vars_info_t, heap);
+static VEC (ipa_reference_vars_info_t, heap) *ipa_reference_vars_vector;
+DEF_VEC_P (ipa_reference_optimization_summary_t);
+DEF_VEC_ALLOC_P (ipa_reference_optimization_summary_t, heap);
+static VEC (ipa_reference_optimization_summary_t, heap) *ipa_reference_opt_sum_vector;
-bitmap
-ipa_reference_get_written_local (tree fn)
+/* Return the ipa_reference_vars structure starting from the cgraph NODE. */
+static inline ipa_reference_vars_info_t
+get_reference_vars_info (struct cgraph_node *node)
{
- ipa_reference_local_vars_info_t l = get_local_reference_vars_info (fn);
- if (l)
- return l->statics_written;
- else
+ if (!ipa_reference_vars_vector
+ || VEC_length (ipa_reference_vars_info_t,
+ ipa_reference_vars_vector) <= (unsigned int) node->uid)
return NULL;
+ return VEC_index (ipa_reference_vars_info_t, ipa_reference_vars_vector,
+ node->uid);
}
-/* Return a bitmap indexed by VAR_DECL uid for the static variables
- that are read during the execution of the function FN. Returns
- NULL if no data is available. */
-
-bitmap
-ipa_reference_get_read_global (tree fn)
+/* Return the ipa_reference_vars structure starting from the cgraph NODE. */
+static inline ipa_reference_optimization_summary_t
+get_reference_optimization_summary (struct cgraph_node *node)
{
- ipa_reference_global_vars_info_t g = get_global_reference_vars_info (fn);
- if (g)
- return g->statics_read;
- else
+ if (!ipa_reference_opt_sum_vector
+ || (VEC_length (ipa_reference_optimization_summary_t,
+ ipa_reference_opt_sum_vector)
+ <= (unsigned int) node->uid))
return NULL;
+ return VEC_index (ipa_reference_optimization_summary_t, ipa_reference_opt_sum_vector,
+ node->uid);
}
-/* Return a bitmap indexed by VAR_DECL uid for the static variables
- that are written during the execution of the function FN. Note
- that variables written may or may not be read during the function
- call. Returns NULL if no data is available. */
+/* Return the ipa_reference_vars structure starting from the cgraph NODE. */
+static inline void
+set_reference_vars_info (struct cgraph_node *node,
+ ipa_reference_vars_info_t info)
+{
+ if (!ipa_reference_vars_vector
+ || VEC_length (ipa_reference_vars_info_t,
+ ipa_reference_vars_vector) <= (unsigned int) node->uid)
+ VEC_safe_grow_cleared (ipa_reference_vars_info_t, heap,
+ ipa_reference_vars_vector, node->uid + 1);
+ VEC_replace (ipa_reference_vars_info_t, ipa_reference_vars_vector,
+ node->uid, info);
+}
-bitmap
-ipa_reference_get_written_global (tree fn)
+/* Return the ipa_reference_vars structure starting from the cgraph NODE. */
+static inline void
+set_reference_optimization_summary (struct cgraph_node *node,
+ ipa_reference_optimization_summary_t info)
{
- ipa_reference_global_vars_info_t g = get_global_reference_vars_info (fn);
- if (g)
- return g->statics_written;
- else
- return NULL;
+ if (!ipa_reference_opt_sum_vector
+ || (VEC_length (ipa_reference_optimization_summary_t,
+ ipa_reference_opt_sum_vector)
+ <= (unsigned int) node->uid))
+ VEC_safe_grow_cleared (ipa_reference_optimization_summary_t,
+ heap, ipa_reference_opt_sum_vector, node->uid + 1);
+ VEC_replace (ipa_reference_optimization_summary_t,
+ ipa_reference_opt_sum_vector, node->uid, info);
}
/* Return a bitmap indexed by_DECL_UID uid for the static variables
that are not read during the execution of the function FN. Returns
NULL if no data is available. */
-bitmap
-ipa_reference_get_not_read_global (tree fn)
+bitmap
+ipa_reference_get_not_read_global (struct cgraph_node *fn)
{
- ipa_reference_global_vars_info_t g = get_global_reference_vars_info (fn);
- if (g)
- return g->statics_not_read;
+ ipa_reference_optimization_summary_t info;
+
+ info = get_reference_optimization_summary (cgraph_function_node (fn, NULL));
+ if (info)
+ return info->statics_not_read;
+ else if (flags_from_decl_or_type (fn->decl) & ECF_LEAF)
+ return all_module_statics;
else
return NULL;
}
that variables written may or may not be read during the function
call. Returns NULL if no data is available. */
-bitmap
-ipa_reference_get_not_written_global (tree fn)
+bitmap
+ipa_reference_get_not_written_global (struct cgraph_node *fn)
{
- ipa_reference_global_vars_info_t g = get_global_reference_vars_info (fn);
- if (g)
- return g->statics_not_written;
+ ipa_reference_optimization_summary_t info;
+
+ info = get_reference_optimization_summary (fn);
+ if (info)
+ return info->statics_not_written;
+ else if (flags_from_decl_or_type (fn->decl) & ECF_LEAF)
+ return all_module_statics;
else
return NULL;
}
/* Add VAR to all_module_statics and the two
reference_vars_to_consider* sets. */
-static inline void
-add_static_var (tree var)
+static inline void
+add_static_var (tree var)
{
int uid = DECL_UID (var);
- if (!bitmap_bit_p (all_module_statics, uid))
- {
- splay_tree_insert (reference_vars_to_consider,
- uid, (splay_tree_value)var);
- bitmap_set_bit (all_module_statics, uid);
- }
+ gcc_assert (TREE_CODE (var) == VAR_DECL);
+ if (dump_file)
+ splay_tree_insert (reference_vars_to_consider,
+ uid, (splay_tree_value)var);
+ bitmap_set_bit (all_module_statics, uid);
}
/* Return true if the variable T is the right kind of static variable to
perform compilation unit scope escape analysis. */
-static inline bool
-has_proper_scope_for_analysis (tree t)
+static inline bool
+is_proper_for_analysis (tree t)
{
+ /* We handle only variables whose address is never taken. */
+ if (TREE_ADDRESSABLE (t))
+ return false;
+
/* If the variable has the "used" attribute, treat it as if it had a
been touched by the devil. */
- if (lookup_attribute ("used", DECL_ATTRIBUTES (t)))
+ if (DECL_PRESERVE_P (t))
return false;
/* 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 false;
-
- /* Do not care about a local automatic that is not static. */
- if (!TREE_STATIC (t) && !DECL_EXTERNAL (t))
+ if (TREE_THIS_VOLATILE (t))
return false;
- if (DECL_EXTERNAL (t) || TREE_PUBLIC (t))
+ /* We do not need to analyze readonly vars, we already know they do not
+ alias. */
+ if (TREE_READONLY (t))
return false;
/* We cannot touch decls where the type needs constructing. */
/* This is a variable we care about. Check if we have seen it
before, and if not add it the set of variables we care about. */
- if (!bitmap_bit_p (all_module_statics, DECL_UID (t)))
+ if (all_module_statics
+ && !bitmap_bit_p (all_module_statics, DECL_UID (t)))
add_static_var (t);
return true;
}
-/* If T is a VAR_DECL for a static that we are interested in, add the
- uid to the bitmap. */
-
-static void
-check_operand (ipa_reference_local_vars_info_t local,
- tree t, bool checking_write)
-{
- if (!t) return;
-
- if ((TREE_CODE (t) == VAR_DECL || TREE_CODE (t) == FUNCTION_DECL)
- && (has_proper_scope_for_analysis (t)))
- {
- if (checking_write)
- {
- if (local)
- bitmap_set_bit (local->statics_written, DECL_UID (t));
- /* Mark the write so we can tell which statics are
- readonly. */
- bitmap_set_bit (module_statics_written, DECL_UID (t));
- }
- else if (local)
- bitmap_set_bit (local->statics_read, DECL_UID (t));
- }
-}
-
-/* Examine tree T for references to static variables. All internal
- references like array references or indirect references are added
- to the READ_BM. Direct references are added to either READ_BM or
- WRITE_BM depending on the value of CHECKING_WRITE. */
-
-static void
-check_tree (ipa_reference_local_vars_info_t local, tree t, bool checking_write)
-{
- if ((TREE_CODE (t) == EXC_PTR_EXPR) || (TREE_CODE (t) == FILTER_EXPR))
- return;
-
- while (TREE_CODE (t) == REALPART_EXPR
- || TREE_CODE (t) == IMAGPART_EXPR
- || handled_component_p (t))
- {
- if (TREE_CODE (t) == ARRAY_REF)
- check_operand (local, TREE_OPERAND (t, 1), false);
- t = TREE_OPERAND (t, 0);
- }
-
- /* The bottom of an indirect reference can only be read, not
- written. So just recurse and whatever we find, check it against
- the read bitmaps. */
-
- /* if (INDIRECT_REF_P (t) || TREE_CODE (t) == MEM_REF) */
- /* FIXME when we have array_ref's of pointers. */
- if (INDIRECT_REF_P (t))
- check_tree (local, TREE_OPERAND (t, 0), false);
-
- if (SSA_VAR_P (t))
- check_operand (local, t, checking_write);
-}
-
-/* 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);
- if (TREE_CODE (x) == VAR_DECL || TREE_CODE (x) == FUNCTION_DECL)
- if (has_proper_scope_for_analysis (x))
- bitmap_set_bit (module_statics_escape, DECL_UID (x));
- }
-}
-
-/* Check to see if T is a read or address of operation on a static var
- we are interested in analyzing. LOCAL is passed in to get access
- to its bit vectors. Local is NULL if this is called from a static
- initializer. */
-
-static void
-check_rhs_var (ipa_reference_local_vars_info_t local, tree t)
-{
- look_for_address_of (t);
-
- if (local == NULL)
- return;
-
- check_tree(local, t, false);
-}
-
-/* Check to see if T is an assignment to a static var we are
- interested in analyzing. LOCAL is passed in to get access to its bit
- vectors. */
-
-static void
-check_lhs_var (ipa_reference_local_vars_info_t local, tree t)
-{
- if (local == NULL)
- return;
-
- check_tree(local, t, true);
-}
-
-/* This is a scaled down version of get_asm_expr_operands from
- tree_ssa_operands.c. The version there runs much later and assumes
- that aliasing information is already available. Here we are just
- trying to find if the set of inputs and outputs contain references
- or address of operations to local static variables. FN is the
- function being analyzed and STMT is the actual asm statement. */
-
-static void
-get_asm_expr_operands (ipa_reference_local_vars_info_t local, tree stmt)
-{
- int noutputs = list_length (ASM_OUTPUTS (stmt));
- const char **oconstraints
- = (const char **) alloca ((noutputs) * sizeof (const char *));
- int i;
- tree link;
- const char *constraint;
- bool allows_mem, allows_reg, is_inout;
-
- for (i=0, link = ASM_OUTPUTS (stmt); link; ++i, link = TREE_CHAIN (link))
- {
- oconstraints[i] = constraint
- = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link)));
- parse_output_constraint (&constraint, i, 0, 0,
- &allows_mem, &allows_reg, &is_inout);
-
- check_lhs_var (local, TREE_VALUE (link));
- }
-
- for (link = ASM_INPUTS (stmt); link; link = TREE_CHAIN (link))
- {
- constraint
- = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link)));
- parse_input_constraint (&constraint, 0, 0, noutputs, 0,
- oconstraints, &allows_mem, &allows_reg);
-
- check_rhs_var (local, TREE_VALUE (link));
- }
-
- for (link = ASM_CLOBBERS (stmt); link; link = TREE_CHAIN (link))
- if (simple_cst_equal(TREE_VALUE (link), memory_identifier_string) == 1)
- {
- /* Abandon all hope, ye who enter here. */
- local->calls_read_all = true;
- local->calls_write_all = true;
- }
-}
-
-/* Check the parameters of a function call from CALLER to CALL_EXPR to
- see if any of them are static vars. Also check to see if this is
- either an indirect call, a call outside the compilation unit, or
- has special attributes that effect the clobbers. The caller
- parameter is the tree node for the caller and the second operand is
- the tree node for the entire call expression. */
-
-static void
-check_call (ipa_reference_local_vars_info_t local, tree call_expr)
-{
- int flags = call_expr_flags (call_expr);
- tree operand;
- tree callee_t = get_callee_fndecl (call_expr);
- enum availability avail = AVAIL_NOT_AVAILABLE;
- call_expr_arg_iterator iter;
-
- FOR_EACH_CALL_EXPR_ARG (operand, iter, call_expr)
- check_rhs_var (local, operand);
-
- if (callee_t)
- {
- struct cgraph_node* callee = cgraph_node(callee_t);
- avail = cgraph_function_body_availability (callee);
- }
-
- if (avail == AVAIL_NOT_AVAILABLE || avail == AVAIL_OVERWRITABLE)
- if (local)
- {
- if (flags & ECF_PURE)
- local->calls_read_all = true;
- else
- {
- local->calls_read_all = true;
- local->calls_write_all = true;
- }
- }
-}
-
-/* TP is the part of the tree currently under the microscope.
- WALK_SUBTREES is part of the walk_tree api but is unused here.
- DATA is cgraph_node of the function being walked. */
-
-/* FIXME: When this is converted to run over SSA form, this code
- should be converted to use the operand scanner. */
-
-static tree
-scan_for_static_refs (tree *tp,
- int *walk_subtrees,
- void *data)
-{
- struct cgraph_node *fn = (struct cgraph_node *) data;
- tree t = *tp;
- ipa_reference_local_vars_info_t local = NULL;
- if (fn)
- local = get_reference_vars_info_from_cgraph (fn)->local;
-
- switch (TREE_CODE (t))
- {
- case VAR_DECL:
- if (DECL_INITIAL (t))
- walk_tree (&DECL_INITIAL (t), scan_for_static_refs, fn, visited_nodes);
- *walk_subtrees = 0;
- break;
-
- case GIMPLE_MODIFY_STMT:
- {
- /* First look on the lhs and see what variable is stored to */
- tree lhs = GIMPLE_STMT_OPERAND (t, 0);
- tree rhs = GIMPLE_STMT_OPERAND (t, 1);
- check_lhs_var (local, lhs);
-
- /* 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 (TREE_CODE (rhs)))
- {
- case tcc_binary:
- case tcc_comparison:
- {
- tree op0 = TREE_OPERAND (rhs, 0);
- tree op1 = TREE_OPERAND (rhs, 1);
- check_rhs_var (local, op0);
- check_rhs_var (local, op1);
- }
- break;
- case tcc_unary:
- {
- tree op0 = TREE_OPERAND (rhs, 0);
- check_rhs_var (local, op0);
- }
-
- break;
- case tcc_reference:
- check_rhs_var (local, rhs);
- break;
- case tcc_declaration:
- check_rhs_var (local, rhs);
- break;
- case tcc_expression:
- switch (TREE_CODE (rhs))
- {
- case ADDR_EXPR:
- check_rhs_var (local, rhs);
- break;
- default:
- break;
- }
- break;
- case tcc_vl_exp:
- switch (TREE_CODE (rhs))
- {
- case CALL_EXPR:
- check_call (local, rhs);
- break;
- default:
- break;
- }
- break;
- default:
- break;
- }
- *walk_subtrees = 0;
- }
- break;
-
- case ADDR_EXPR:
- /* This case is here to find addresses on rhs of constructors in
- decl_initial of static variables. */
- check_rhs_var (local, t);
- *walk_subtrees = 0;
- break;
-
- case LABEL_EXPR:
- if (DECL_NONLOCAL (TREE_OPERAND (t, 0)))
- {
- /* Target of long jump. */
- local->calls_read_all = true;
- local->calls_write_all = true;
- }
- break;
-
- case CALL_EXPR:
- check_call (local, t);
- *walk_subtrees = 0;
- break;
-
- case ASM_EXPR:
- get_asm_expr_operands (local, t);
- *walk_subtrees = 0;
- break;
-
- default:
- break;
- }
- return NULL;
-}
-
-
-/* Lookup the tree node for the static variable that has UID. */
-static tree
-get_static_decl (int index)
-{
- splay_tree_node stn =
- splay_tree_lookup (reference_vars_to_consider, index);
- if (stn)
- return (tree)stn->value;
- return NULL;
-}
-
/* Lookup the tree node for the static variable that has UID and
convert the name to a string for debugging. */
static const char *
get_static_name (int index)
{
- splay_tree_node stn =
+ splay_tree_node stn =
splay_tree_lookup (reference_vars_to_consider, index);
if (stn)
return lang_hooks.decl_printable_name ((tree)(stn->value), 2);
return NULL;
}
-/* Or in all of the bits from every callee into X, the caller's, bit
- vector. There are several cases to check to avoid the sparse
+/* Or in all of the bits from every callee of X into X_GLOBAL, the caller's cycle,
+ bit vector. There are several cases to check to avoid the sparse
bitmap oring. */
static void
-propagate_bits (struct cgraph_node *x)
+propagate_bits (ipa_reference_global_vars_info_t x_global, struct cgraph_node *x)
{
- ipa_reference_vars_info_t x_info = get_reference_vars_info_from_cgraph (x);
- ipa_reference_global_vars_info_t x_global = x_info->global;
-
struct cgraph_edge *e;
- for (e = x->callees; e; e = e->next_callee)
+ for (e = x->callees; e; e = e->next_callee)
{
- struct cgraph_node *y = e->callee;
-
- /* Only look at the master nodes and skip external nodes. */
- y = cgraph_master_clone (y);
- if (y)
+ enum availability avail;
+ struct cgraph_node *y = cgraph_function_node (e->callee, &avail);
+
+ if (!y)
+ continue;
+ /* Only look into nodes we can propagate something. */
+ if (avail > AVAIL_OVERWRITABLE
+ || (avail == AVAIL_OVERWRITABLE
+ && (flags_from_decl_or_type (y->decl) & ECF_LEAF)))
{
- if (get_reference_vars_info_from_cgraph (y))
+ int flags = flags_from_decl_or_type (y->decl);
+ if (get_reference_vars_info (y))
{
- ipa_reference_vars_info_t y_info = get_reference_vars_info_from_cgraph (y);
- ipa_reference_global_vars_info_t y_global = y_info->global;
-
+ ipa_reference_vars_info_t y_info
+ = get_reference_vars_info (y);
+ ipa_reference_global_vars_info_t y_global = &y_info->global;
+
+ /* Calls in current cycle do not have global computed yet. */
+ if (!y_global->statics_read)
+ continue;
+
+ /* If function is declared const, it reads no memory even if it
+ seems so to local analysis. */
+ if (flags & ECF_CONST)
+ continue;
+
if (x_global->statics_read
!= all_module_statics)
{
- if (y_global->statics_read
+ if (y_global->statics_read
== all_module_statics)
{
BITMAP_FREE (x_global->statics_read);
- x_global->statics_read
+ x_global->statics_read
= all_module_statics;
}
/* Skip bitmaps that are pointer equal to node's bitmap
(no reason to spin within the cycle). */
- else if (x_global->statics_read
+ else if (x_global->statics_read
!= y_global->statics_read)
bitmap_ior_into (x_global->statics_read,
y_global->statics_read);
}
-
- if (x_global->statics_written
+
+ /* If function is declared pure, it has no stores even if it
+ seems so to local analysis; If we can not return from here,
+ we can safely ignore the call. */
+ if ((flags & ECF_PURE)
+ || cgraph_edge_cannot_lead_to_return (e))
+ continue;
+
+ if (x_global->statics_written
!= all_module_statics)
{
- if (y_global->statics_written
+ if (y_global->statics_written
== all_module_statics)
{
BITMAP_FREE (x_global->statics_written);
- x_global->statics_written
+ x_global->statics_written
= all_module_statics;
}
/* Skip bitmaps that are pointer equal to node's bitmap
(no reason to spin within the cycle). */
- else if (x_global->statics_written
+ else if (x_global->statics_written
!= y_global->statics_written)
bitmap_ior_into (x_global->statics_written,
y_global->statics_written);
}
}
- else
- {
- gcc_unreachable ();
- }
+ else
+ gcc_unreachable ();
}
}
}
-/* Look at all of the callees of X to see which ones represent inlined
- calls. For each of these callees, merge their local info into
- TARGET and check their children recursively.
-
- This function goes away when Jan changes the inliner and IPA
- analysis so that this is not run between the time when inlining
- decisions are made and when the inlining actually occurs. */
-
-static void
-merge_callee_local_info (struct cgraph_node *target,
- struct cgraph_node *x)
+/* The init routine for analyzing global static variable usage. See
+ comments at top for description. */
+static void
+ipa_init (void)
{
- struct cgraph_edge *e;
- ipa_reference_local_vars_info_t x_l =
- get_reference_vars_info_from_cgraph (target)->local;
+ static bool init_p = false;
- /* Make the world safe for tail recursion. */
- struct ipa_dfs_info *node_info = (struct ipa_dfs_info *) x->aux;
-
- if (node_info->aux)
+ if (init_p)
return;
- node_info->aux = x;
+ init_p = true;
- for (e = x->callees; e; e = e->next_callee)
- {
- struct cgraph_node *y = e->callee;
- if (y->global.inlined_to)
- {
- ipa_reference_vars_info_t y_info;
- ipa_reference_local_vars_info_t y_l;
- struct cgraph_node* orig_y = y;
-
- y = cgraph_master_clone (y);
- if (y)
- {
- y_info = get_reference_vars_info_from_cgraph (y);
- y_l = y_info->local;
- if (x_l != y_l)
- {
- bitmap_ior_into (x_l->statics_read,
- y_l->statics_read);
- bitmap_ior_into (x_l->statics_written,
- y_l->statics_written);
- }
- x_l->calls_read_all |= y_l->calls_read_all;
- x_l->calls_write_all |= y_l->calls_write_all;
- merge_callee_local_info (target, y);
- }
- else
- {
- fprintf(stderr, "suspect inlining of ");
- dump_cgraph_node (stderr, orig_y);
- fprintf(stderr, "\ninto ");
- dump_cgraph_node (stderr, target);
- dump_cgraph (stderr);
- gcc_assert(false);
- }
- }
- }
+ if (dump_file)
+ reference_vars_to_consider = splay_tree_new (splay_tree_compare_ints, 0, 0);
- node_info->aux = NULL;
-}
+ bitmap_obstack_initialize (&local_info_obstack);
+ bitmap_obstack_initialize (&optimization_summary_obstack);
+ all_module_statics = BITMAP_ALLOC (&optimization_summary_obstack);
-/* The init routine for analyzing global static variable usage. See
- comments at top for description. */
-static void
-ipa_init (void)
-{
- struct cgraph_node *node;
- memory_identifier_string = build_string(7, "memory");
+ node_removal_hook_holder =
+ cgraph_add_node_removal_hook (&remove_node_data, NULL);
+ node_duplication_hook_holder =
+ cgraph_add_node_duplication_hook (&duplicate_node_data, NULL);
+}
- reference_vars_to_consider =
- splay_tree_new_ggc (splay_tree_compare_ints);
- bitmap_obstack_initialize (&ipa_obstack);
- module_statics_escape = BITMAP_ALLOC (&ipa_obstack);
- module_statics_written = BITMAP_ALLOC (&ipa_obstack);
- all_module_statics = BITMAP_ALLOC (&ipa_obstack);
+/* Set up the persistent info for FN. */
- /* This will add NODE->DECL to the splay trees. */
- for (node = cgraph_nodes; node; node = node->next)
- has_proper_scope_for_analysis (node->decl);
+static ipa_reference_local_vars_info_t
+init_function_info (struct cgraph_node *fn)
+{
+ ipa_reference_vars_info_t info
+ = XCNEW (struct ipa_reference_vars_info_d);
- /* There are some shared nodes, in particular the initializers on
- static declarations. We do not need to scan them more than once
- since all we would be interested in are the addressof
- operations. */
- visited_nodes = pointer_set_create ();
-}
+ /* Add the info to the tree's annotation. */
+ set_reference_vars_info (fn, info);
-/* Check out the rhs of a static or global initialization VNODE to see
- 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. */
+ info->local.statics_read = BITMAP_ALLOC (&local_info_obstack);
+ info->local.statics_written = BITMAP_ALLOC (&local_info_obstack);
-static void
-analyze_variable (struct varpool_node *vnode)
-{
- tree global = vnode->decl;
- walk_tree (&DECL_INITIAL (global), scan_for_static_refs,
- NULL, visited_nodes);
+ return &info->local;
}
+
/* This is the main routine for finding the reference patterns for
global variables within a function FN. */
static void
analyze_function (struct cgraph_node *fn)
{
- ipa_reference_vars_info_t info
- = XCNEW (struct ipa_reference_vars_info_d);
- ipa_reference_local_vars_info_t l
- = XCNEW (struct ipa_reference_local_vars_info_d);
- tree decl = fn->decl;
+ ipa_reference_local_vars_info_t local;
+ struct ipa_ref *ref;
+ int i;
+ tree var;
- /* Add the info to the tree's annotation. */
- get_function_ann (fn->decl)->reference_vars_info = info;
+ local = init_function_info (fn);
+ for (i = 0; ipa_ref_list_reference_iterate (&fn->ref_list, i, ref); i++)
+ {
+ if (ref->refered_type != IPA_REF_VARPOOL)
+ continue;
+ var = ipa_ref_varpool_node (ref)->decl;
+ if (ipa_ref_varpool_node (ref)->externally_visible
+ || !ipa_ref_varpool_node (ref)->analyzed
+ || !is_proper_for_analysis (var))
+ continue;
+ switch (ref->use)
+ {
+ case IPA_REF_LOAD:
+ bitmap_set_bit (local->statics_read, DECL_UID (var));
+ break;
+ case IPA_REF_STORE:
+ if (ipa_ref_cannot_lead_to_return (ref))
+ break;
+ bitmap_set_bit (local->statics_written, DECL_UID (var));
+ break;
+ case IPA_REF_ADDR:
+ gcc_unreachable ();
+ break;
+ }
+ }
- info->local = l;
- l->statics_read = BITMAP_ALLOC (&ipa_obstack);
- l->statics_written = BITMAP_ALLOC (&ipa_obstack);
+ if (cgraph_node_cannot_return (fn))
+ bitmap_clear (local->statics_written);
+}
- if (dump_file)
- fprintf (dump_file, "\n local analysis of %s\n", cgraph_node_name (fn));
-
- {
- struct function *this_cfun = DECL_STRUCT_FUNCTION (decl);
- basic_block this_block;
+static bitmap
+copy_global_bitmap (bitmap src)
+{
+ bitmap dst;
+ if (!src)
+ return NULL;
+ if (src == all_module_statics)
+ return all_module_statics;
+ dst = BITMAP_ALLOC (&optimization_summary_obstack);
+ bitmap_copy (dst, src);
+ return dst;
+}
- FOR_EACH_BB_FN (this_block, this_cfun)
- {
- block_stmt_iterator bsi;
- tree phi, op;
- use_operand_p use;
- ssa_op_iter iter;
- /* Find the addresses taken in phi node arguments. */
- for (phi = phi_nodes (this_block); phi; phi = PHI_CHAIN (phi))
- {
- FOR_EACH_PHI_ARG (use, phi, iter, SSA_OP_USE)
- {
- op = USE_FROM_PTR (use);
- if (TREE_CODE (op) == ADDR_EXPR)
- check_rhs_var (l, op);
- }
- }
+/* Called when new clone is inserted to callgraph late. */
- for (bsi = bsi_start (this_block); !bsi_end_p (bsi); bsi_next (&bsi))
- walk_tree (bsi_stmt_ptr (bsi), scan_for_static_refs,
- fn, visited_nodes);
- }
- }
+static void
+duplicate_node_data (struct cgraph_node *src, struct cgraph_node *dst,
+ void *data ATTRIBUTE_UNUSED)
+{
+ ipa_reference_optimization_summary_t ginfo;
+ ipa_reference_optimization_summary_t dst_ginfo;
- /* There may be const decls with interesting right hand sides. */
- if (DECL_STRUCT_FUNCTION (decl))
- {
- tree step;
- 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))
- walk_tree (&DECL_INITIAL (var), scan_for_static_refs,
- fn, visited_nodes);
- }
- }
+ ginfo = get_reference_optimization_summary (src);
+ if (!ginfo)
+ return;
+ dst_ginfo = XCNEW (struct ipa_reference_optimization_summary_d);
+ set_reference_optimization_summary (dst, dst_ginfo);
+ dst_ginfo->statics_not_read = copy_global_bitmap (ginfo->statics_not_read);
+ dst_ginfo->statics_not_written = copy_global_bitmap (ginfo->statics_not_written);
}
-/* If FN is avail == AVAIL_OVERWRITABLE, replace the effects bit
- vectors with worst case bit vectors. We had to analyze it above to
- find out if it took the address of any statics. However, now that
- we know that, we can get rid of all of the other side effects. */
+/* Called when node is removed. */
static void
-clean_function (struct cgraph_node *fn)
+remove_node_data (struct cgraph_node *node, void *data ATTRIBUTE_UNUSED)
{
- ipa_reference_vars_info_t info = get_reference_vars_info_from_cgraph (fn);
- ipa_reference_local_vars_info_t l = info->local;
- ipa_reference_global_vars_info_t g = info->global;
-
- if (l)
+ ipa_reference_optimization_summary_t ginfo;
+ ginfo = get_reference_optimization_summary (node);
+ if (ginfo)
{
- if (l->statics_read
- && l->statics_read != all_module_statics)
- BITMAP_FREE (l->statics_read);
- if (l->statics_written
- &&l->statics_written != all_module_statics)
- BITMAP_FREE (l->statics_written);
- free (l);
+ if (ginfo->statics_not_read
+ && ginfo->statics_not_read != all_module_statics)
+ BITMAP_FREE (ginfo->statics_not_read);
+
+ if (ginfo->statics_not_written
+ && ginfo->statics_not_written != all_module_statics)
+ BITMAP_FREE (ginfo->statics_not_written);
+ free (ginfo);
+ set_reference_optimization_summary (node, NULL);
}
-
- if (g)
- {
- if (g->statics_read
- && g->statics_read != all_module_statics)
- BITMAP_FREE (g->statics_read);
-
- if (g->statics_written
- && g->statics_written != all_module_statics)
- BITMAP_FREE (g->statics_written);
-
- if (g->statics_not_read
- && g->statics_not_read != all_module_statics)
- BITMAP_FREE (g->statics_not_read);
-
- if (g->statics_not_written
- && g->statics_not_written != all_module_statics)
- BITMAP_FREE (g->statics_not_written);
- free (g);
- }
-
-
- free (get_function_ann (fn->decl)->reference_vars_info);
- get_function_ann (fn->decl)->reference_vars_info = NULL;
}
-\f
-/* Produce the global information by preforming a transitive closure
- on the local information that was produced by ipa_analyze_function
- and ipa_analyze_variable. */
+/* Analyze each function in the cgraph to see which global or statics
+ are read or written. */
-static unsigned int
-static_execute (void)
+static void
+generate_summary (void)
{
struct cgraph_node *node;
- struct varpool_node *vnode;
- struct cgraph_node *w;
- struct cgraph_node **order =
- XCNEWVEC (struct cgraph_node *, cgraph_n_nodes);
- int order_pos = ipa_utils_reduced_inorder (order, false, true);
- int i;
+ unsigned int index;
+ bitmap_iterator bi;
+ bitmap bm_temp;
ipa_init ();
+ bm_temp = BITMAP_ALLOC (&local_info_obstack);
- /* Process all of the variables first. */
- FOR_EACH_STATIC_INITIALIZER (vnode)
- analyze_variable (vnode);
-
- /* 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 static variable to escape. The code that can
- overwrite such a function cannot access the statics because it
- would not be in the same compilation unit. When the analysis is
- finished, the computed information of these AVAIL_OVERWRITABLE is
- replaced with worst case info.
- */
+ /* Process all of the functions next. */
for (node = cgraph_nodes; node; node = node->next)
- if (node->analyzed
- && (cgraph_is_master_clone (node)
- || (cgraph_function_body_availability (node)
- == AVAIL_OVERWRITABLE)))
+ if (node->analyzed)
analyze_function (node);
- pointer_set_destroy (visited_nodes);
- visited_nodes = NULL;
- if (dump_file)
- dump_cgraph (dump_file);
-
- /* Prune out the variables that were found to behave badly
- (i.e. have their address taken). */
- {
- unsigned int index;
- bitmap_iterator bi;
- bitmap module_statics_readonly = BITMAP_ALLOC (&ipa_obstack);
- bitmap bm_temp = BITMAP_ALLOC (&ipa_obstack);
-
- EXECUTE_IF_SET_IN_BITMAP (module_statics_escape, 0, index, bi)
- {
- splay_tree_remove (reference_vars_to_consider, index);
- }
-
- bitmap_and_compl_into (all_module_statics,
- module_statics_escape);
-
- bitmap_and_compl (module_statics_readonly, all_module_statics,
- module_statics_written);
-
- /* If the address is not taken, we can unset the addressable bit
- on this variable. */
+ if (dump_file)
EXECUTE_IF_SET_IN_BITMAP (all_module_statics, 0, index, bi)
{
- tree var = get_static_decl (index);
- TREE_ADDRESSABLE (var) = 0;
- if (dump_file)
- fprintf (dump_file, "Not TREE_ADDRESSABLE var %s\n",
- get_static_name (index));
- }
-
- /* If the variable is never written, we can set the TREE_READONLY
- flag. Additionally if it has a DECL_INITIAL that is made up of
- constants we can treat the entire global as a constant. */
-
- bitmap_and_compl (module_statics_readonly, all_module_statics,
- module_statics_written);
- EXECUTE_IF_SET_IN_BITMAP (module_statics_readonly, 0, index, bi)
- {
- tree var = get_static_decl (index);
-
- /* Readonly on a function decl is very different from the
- variable. */
- if (TREE_CODE (var) == FUNCTION_DECL)
- continue;
-
- /* Ignore variables in named sections - changing TREE_READONLY
- changes the section flags, potentially causing conflicts with
- other variables in the same named section. */
- if (DECL_SECTION_NAME (var) == NULL_TREE)
- {
- TREE_READONLY (var) = 1;
- if (dump_file)
- fprintf (dump_file, "read-only var %s\n",
- get_static_name (index));
- }
- }
-
- BITMAP_FREE(module_statics_escape);
- BITMAP_FREE(module_statics_written);
-
- if (dump_file)
- EXECUTE_IF_SET_IN_BITMAP (all_module_statics, 0, index, bi)
- {
- fprintf (dump_file, "\nPromotable global:%s",
- get_static_name (index));
- }
-
- for (i = 0; i < order_pos; i++ )
- {
- ipa_reference_local_vars_info_t l;
- node = order[i];
- l = get_reference_vars_info_from_cgraph (node)->local;
-
- /* Any variables that are not in all_module_statics are
- removed from the local maps. This will include all of the
- variables that were found to escape in the function
- scanning. */
- bitmap_and_into (l->statics_read,
- all_module_statics);
- bitmap_and_into (l->statics_written,
- all_module_statics);
+ fprintf (dump_file, "\nPromotable global:%s",
+ get_static_name (index));
}
- BITMAP_FREE(module_statics_readonly);
- BITMAP_FREE(bm_temp);
- }
+ BITMAP_FREE(bm_temp);
if (dump_file)
- {
- for (i = 0; i < order_pos; i++ )
+ for (node = cgraph_nodes; node; node = node->next)
+ if (cgraph_function_body_availability (node) >= AVAIL_OVERWRITABLE)
{
- unsigned int index;
ipa_reference_local_vars_info_t l;
+ unsigned int index;
bitmap_iterator bi;
- node = order[i];
- l = get_reference_vars_info_from_cgraph (node)->local;
- fprintf (dump_file,
- "\nFunction name:%s/%i:",
+ l = &get_reference_vars_info (node)->local;
+ fprintf (dump_file,
+ "\nFunction name:%s/%i:",
cgraph_node_name (node), node->uid);
fprintf (dump_file, "\n locals read: ");
- EXECUTE_IF_SET_IN_BITMAP (l->statics_read,
- 0, index, bi)
- {
- fprintf (dump_file, "%s ",
- get_static_name (index));
- }
+ if (l->statics_read)
+ EXECUTE_IF_SET_IN_BITMAP (l->statics_read,
+ 0, index, bi)
+ {
+ fprintf (dump_file, "%s ",
+ get_static_name (index));
+ }
fprintf (dump_file, "\n locals written: ");
- EXECUTE_IF_SET_IN_BITMAP (l->statics_written,
- 0, index, bi)
- {
- fprintf(dump_file, "%s ",
- get_static_name (index));
- }
+ if (l->statics_written)
+ EXECUTE_IF_SET_IN_BITMAP (l->statics_written,
+ 0, index, bi)
+ {
+ fprintf(dump_file, "%s ",
+ get_static_name (index));
+ }
}
+}
+\f
+/* Set READ_ALL/WRITE_ALL based on decl flags of NODE. */
+
+static void
+read_write_all_from_decl (struct cgraph_node *node, bool * read_all,
+ bool * write_all)
+{
+ tree decl = node->decl;
+ int flags = flags_from_decl_or_type (decl);
+ if ((flags & ECF_LEAF)
+ && cgraph_function_body_availability (node) <= AVAIL_OVERWRITABLE)
+ ;
+ else if (flags & ECF_CONST)
+ ;
+ else if ((flags & ECF_PURE)
+ || cgraph_node_cannot_return (node))
+ {
+ *read_all = true;
+ if (dump_file && (dump_flags & TDF_DETAILS))
+ fprintf (dump_file, " %s/%i -> read all\n",
+ cgraph_node_name (node), node->uid);
}
+ else
+ {
+ /* TODO: To be able to produce sane results, we should also handle
+ common builtins, in particular throw. */
+ *read_all = true;
+ *write_all = true;
+ if (dump_file && (dump_flags & TDF_DETAILS))
+ fprintf (dump_file, " %s/%i -> read all, write all\n",
+ cgraph_node_name (node), node->uid);
+ }
+}
+
+/* Produce the global information by preforming a transitive closure
+ on the local information that was produced by ipa_analyze_function */
+
+static unsigned int
+propagate (void)
+{
+ struct cgraph_node *node;
+ struct cgraph_node *w;
+ struct cgraph_node **order =
+ XCNEWVEC (struct cgraph_node *, cgraph_n_nodes);
+ int order_pos;
+ int i;
+
+ if (dump_file)
+ dump_cgraph (dump_file);
+
+ ipa_discover_readonly_nonaddressable_vars ();
+ generate_summary ();
/* Propagate the local information thru the call graph to produce
the global information. All the nodes within a cycle will have
the same info so we collapse cycles first. Then we can do the
propagation in one pass from the leaves to the roots. */
- order_pos = ipa_utils_reduced_inorder (order, true, true);
+ order_pos = ipa_reduced_postorder (order, true, true, NULL);
if (dump_file)
- ipa_utils_print_order(dump_file, "reduced", order, order_pos);
+ ipa_print_order (dump_file, "reduced", order, order_pos);
for (i = 0; i < order_pos; i++ )
{
ipa_reference_vars_info_t node_info;
- ipa_reference_global_vars_info_t node_g =
- XCNEW (struct ipa_reference_global_vars_info_d);
+ ipa_reference_global_vars_info_t node_g;
ipa_reference_local_vars_info_t node_l;
-
+ struct cgraph_edge *e, *ie;
+
bool read_all;
bool write_all;
struct ipa_dfs_info * w_info;
node = order[i];
- node_info = get_reference_vars_info_from_cgraph (node);
- if (!node_info)
+ if (node->alias)
+ continue;
+ node_info = get_reference_vars_info (node);
+ gcc_assert (node_info);
+
+
+ if (dump_file && (dump_flags & TDF_DETAILS))
+ fprintf (dump_file, "Starting cycle with %s/%i\n",
+ cgraph_node_name (node), node->uid);
+
+ node_l = &node_info->local;
+ node_g = &node_info->global;
+
+ read_all = false;
+ write_all = false;
+
+ /* When function is overwritable, we can not assume anything. */
+ if (cgraph_function_body_availability (node) <= AVAIL_OVERWRITABLE)
+ read_write_all_from_decl (node, &read_all, &write_all);
+
+ for (e = node->callees; e; e = e->next_callee)
{
- dump_cgraph_node (stderr, node);
- dump_cgraph (stderr);
- gcc_unreachable ();
+ enum availability avail;
+ struct cgraph_node *callee = cgraph_function_node (e->callee, &avail);
+ if (!callee || avail <= AVAIL_OVERWRITABLE)
+ read_write_all_from_decl (callee, &read_all, &write_all);
}
- node_info->global = node_g;
- node_l = node_info->local;
+ for (ie = node->indirect_calls; ie; ie = ie->next_callee)
+ if (!(ie->indirect_info->ecf_flags & ECF_CONST))
+ {
+ read_all = true;
+ if (dump_file && (dump_flags & TDF_DETAILS))
+ fprintf (dump_file, " indirect call -> read all\n");
+ if (!cgraph_edge_cannot_lead_to_return (ie)
+ && !(ie->indirect_info->ecf_flags & ECF_PURE))
+ {
+ if (dump_file && (dump_flags & TDF_DETAILS))
+ fprintf (dump_file, " indirect call -> write all\n");
+ write_all = true;
+ }
+ }
- read_all = node_l->calls_read_all;
- write_all = node_l->calls_write_all;
- /* If any node in a cycle is calls_read_all or calls_write_all
+ /* If any node in a cycle is read_all or write_all
they all are. */
w_info = (struct ipa_dfs_info *) node->aux;
w = w_info->next_cycle;
- while (w)
+ while (w && (!read_all || !write_all))
{
- ipa_reference_local_vars_info_t w_l =
- get_reference_vars_info_from_cgraph (w)->local;
- read_all |= w_l->calls_read_all;
- write_all |= w_l->calls_write_all;
+ if (dump_file && (dump_flags & TDF_DETAILS))
+ fprintf (dump_file, " Visiting %s/%i\n",
+ cgraph_node_name (w), w->uid);
+ /* When function is overwritable, we can not assume anything. */
+ if (cgraph_function_body_availability (w) <= AVAIL_OVERWRITABLE)
+ read_write_all_from_decl (w, &read_all, &write_all);
+
+ for (e = w->callees; e; e = e->next_callee)
+ {
+ enum availability avail;
+ struct cgraph_node *callee = cgraph_function_node (e->callee, &avail);
+
+ if (avail <= AVAIL_OVERWRITABLE)
+ read_write_all_from_decl (callee, &read_all, &write_all);
+ }
+
+ for (ie = w->indirect_calls; ie; ie = ie->next_callee)
+ if (!(ie->indirect_info->ecf_flags & ECF_CONST))
+ {
+ read_all = true;
+ if (dump_file && (dump_flags & TDF_DETAILS))
+ fprintf (dump_file, " indirect call -> read all\n");
+ if (!cgraph_edge_cannot_lead_to_return (ie)
+ && !(ie->indirect_info->ecf_flags & ECF_PURE))
+ {
+ write_all = true;
+ if (dump_file && (dump_flags & TDF_DETAILS))
+ fprintf (dump_file, " indirect call -> write all\n");
+ }
+ }
w_info = (struct ipa_dfs_info *) w->aux;
w = w_info->next_cycle;
}
+
/* Initialized the bitmaps for the reduced nodes */
- if (read_all)
+ if (read_all)
node_g->statics_read = all_module_statics;
- else
+ else
{
- node_g->statics_read = BITMAP_ALLOC (&ipa_obstack);
- bitmap_copy (node_g->statics_read,
+ node_g->statics_read = BITMAP_ALLOC (&local_info_obstack);
+ bitmap_copy (node_g->statics_read,
node_l->statics_read);
}
-
- if (write_all)
+ if (write_all)
node_g->statics_written = all_module_statics;
else
{
- node_g->statics_written = BITMAP_ALLOC (&ipa_obstack);
- bitmap_copy (node_g->statics_written,
+ node_g->statics_written = BITMAP_ALLOC (&local_info_obstack);
+ bitmap_copy (node_g->statics_written,
node_l->statics_written);
}
+ propagate_bits (node_g, node);
w_info = (struct ipa_dfs_info *) node->aux;
w = w_info->next_cycle;
- while (w)
+ while (w && (!read_all || !write_all))
{
- ipa_reference_vars_info_t w_ri =
- get_reference_vars_info_from_cgraph (w);
- ipa_reference_local_vars_info_t w_l = w_ri->local;
+ ipa_reference_vars_info_t w_ri =
+ get_reference_vars_info (w);
+ ipa_reference_local_vars_info_t w_l = &w_ri->local;
+ int flags = flags_from_decl_or_type (w->decl);
- /* All nodes within a cycle share the same global info bitmaps. */
- w_ri->global = node_g;
-
/* These global bitmaps are initialized from the local info
of all of the nodes in the region. However there is no
need to do any work if the bitmaps were set to
all_module_statics. */
- if (!read_all)
+ if (!read_all && !(flags & ECF_CONST))
bitmap_ior_into (node_g->statics_read,
w_l->statics_read);
- if (!write_all)
+ if (!write_all
+ && !(flags & ECF_PURE)
+ && !cgraph_node_cannot_return (w))
bitmap_ior_into (node_g->statics_written,
w_l->statics_written);
+ propagate_bits (node_g, w);
w_info = (struct ipa_dfs_info *) w->aux;
w = w_info->next_cycle;
}
- w = node;
- while (w)
- {
- propagate_bits (w);
- w_info = (struct ipa_dfs_info *) w->aux;
- w = w_info->next_cycle;
- }
- }
-
- /* Need to fix up the local information sets. The information that
- has been gathered so far is preinlining. However, the
- compilation will progress post inlining so the local sets for the
- inlined calls need to be merged into the callers. Note that the
- local sets are not shared between all of the nodes in a cycle so
- those nodes in the cycle must be processed explicitly. */
- for (i = 0; i < order_pos; i++ )
- {
- struct ipa_dfs_info * w_info;
- node = order[i];
- merge_callee_local_info (node, node);
-
+ /* All nodes within a cycle have the same global info bitmaps. */
+ node_info->global = *node_g;
w_info = (struct ipa_dfs_info *) node->aux;
w = w_info->next_cycle;
while (w)
{
- merge_callee_local_info (w, w);
+ ipa_reference_vars_info_t w_ri =
+ get_reference_vars_info (w);
+
+ w_ri->global = *node_g;
+
w_info = (struct ipa_dfs_info *) w->aux;
w = w_info->next_cycle;
}
struct ipa_dfs_info * w_info;
node = order[i];
- node_info = get_reference_vars_info_from_cgraph (node);
- node_g = node_info->global;
- node_l = node_info->local;
- fprintf (dump_file,
- "\nFunction name:%s/%i:",
+ if (node->alias)
+ continue;
+ node_info = get_reference_vars_info (node);
+ node_g = &node_info->global;
+ node_l = &node_info->local;
+ fprintf (dump_file,
+ "\nFunction name:%s/%i:",
cgraph_node_name (node), node->uid);
fprintf (dump_file, "\n locals read: ");
- EXECUTE_IF_SET_IN_BITMAP (node_l->statics_read,
- 0, index, bi)
- {
- fprintf (dump_file, "%s ",
- get_static_name (index));
- }
+ if (node_l->statics_read)
+ EXECUTE_IF_SET_IN_BITMAP (node_l->statics_read,
+ 0, index, bi)
+ {
+ fprintf (dump_file, "%s ",
+ get_static_name (index));
+ }
fprintf (dump_file, "\n locals written: ");
- EXECUTE_IF_SET_IN_BITMAP (node_l->statics_written,
- 0, index, bi)
- {
- fprintf(dump_file, "%s ",
- get_static_name (index));
- }
+ if (node_l->statics_written)
+ EXECUTE_IF_SET_IN_BITMAP (node_l->statics_written,
+ 0, index, bi)
+ {
+ fprintf(dump_file, "%s ",
+ get_static_name (index));
+ }
w_info = (struct ipa_dfs_info *) node->aux;
w = w_info->next_cycle;
- while (w)
+ while (w)
{
- ipa_reference_vars_info_t w_ri =
- get_reference_vars_info_from_cgraph (w);
- ipa_reference_local_vars_info_t w_l = w_ri->local;
+ ipa_reference_vars_info_t w_ri =
+ get_reference_vars_info (w);
+ ipa_reference_local_vars_info_t w_l = &w_ri->local;
fprintf (dump_file, "\n next cycle: %s/%i ",
cgraph_node_name (w), w->uid);
- fprintf (dump_file, "\n locals read: ");
- EXECUTE_IF_SET_IN_BITMAP (w_l->statics_read,
- 0, index, bi)
- {
- fprintf (dump_file, "%s ",
- get_static_name (index));
- }
+ fprintf (dump_file, "\n locals read: ");
+ if (w_l->statics_read)
+ EXECUTE_IF_SET_IN_BITMAP (w_l->statics_read,
+ 0, index, bi)
+ {
+ fprintf (dump_file, "%s ",
+ get_static_name (index));
+ }
fprintf (dump_file, "\n locals written: ");
- EXECUTE_IF_SET_IN_BITMAP (w_l->statics_written,
- 0, index, bi)
- {
- fprintf(dump_file, "%s ",
- get_static_name (index));
- }
-
+ if (w_l->statics_written)
+ EXECUTE_IF_SET_IN_BITMAP (w_l->statics_written,
+ 0, index, bi)
+ {
+ fprintf (dump_file, "%s ",
+ get_static_name (index));
+ }
w_info = (struct ipa_dfs_info *) w->aux;
w = w_info->next_cycle;
}
fprintf (dump_file, "\n globals read: ");
- EXECUTE_IF_SET_IN_BITMAP (node_g->statics_read,
- 0, index, bi)
- {
- fprintf (dump_file, "%s ",
- get_static_name (index));
- }
+ if (node_g->statics_read == all_module_statics)
+ fprintf (dump_file, "ALL");
+ else
+ EXECUTE_IF_SET_IN_BITMAP (node_g->statics_read,
+ 0, index, bi)
+ {
+ fprintf (dump_file, "%s ",
+ get_static_name (index));
+ }
fprintf (dump_file, "\n globals written: ");
- EXECUTE_IF_SET_IN_BITMAP (node_g->statics_written,
- 0, index, bi)
- {
- fprintf (dump_file, "%s ",
- get_static_name (index));
- }
+ if (node_g->statics_written == all_module_statics)
+ fprintf (dump_file, "ALL");
+ else
+ EXECUTE_IF_SET_IN_BITMAP (node_g->statics_written,
+ 0, index, bi)
+ {
+ fprintf (dump_file, "%s ",
+ get_static_name (index));
+ }
}
}
/* Cleanup. */
- for (i = 0; i < order_pos; i++ )
+ for (node = cgraph_nodes; node; node = node->next)
{
ipa_reference_vars_info_t node_info;
ipa_reference_global_vars_info_t node_g;
- node = order[i];
- node_info = get_reference_vars_info_from_cgraph (node);
- node_g = node_info->global;
-
- /* Create the complimentary sets. These are more useful for
- certain apis. */
- node_g->statics_not_read = BITMAP_ALLOC (&ipa_obstack);
- node_g->statics_not_written = BITMAP_ALLOC (&ipa_obstack);
-
- if (node_g->statics_read != all_module_statics)
+ ipa_reference_optimization_summary_t opt;
+
+ if (!node->analyzed || node->alias)
+ continue;
+
+ node_info = get_reference_vars_info (node);
+ if (cgraph_function_body_availability (node) > AVAIL_OVERWRITABLE
+ || (flags_from_decl_or_type (node->decl) & ECF_LEAF))
{
- bitmap_and_compl (node_g->statics_not_read,
- all_module_statics,
- node_g->statics_read);
- }
+ node_g = &node_info->global;
+
+ opt = XCNEW (struct ipa_reference_optimization_summary_d);
+ set_reference_optimization_summary (node, opt);
- if (node_g->statics_written
- != all_module_statics)
- bitmap_and_compl (node_g->statics_not_written,
- all_module_statics,
- node_g->statics_written);
+ /* Create the complimentary sets. */
+
+ if (bitmap_empty_p (node_g->statics_read))
+ opt->statics_not_read = all_module_statics;
+ else
+ {
+ opt->statics_not_read
+ = BITMAP_ALLOC (&optimization_summary_obstack);
+ if (node_g->statics_read != all_module_statics)
+ bitmap_and_compl (opt->statics_not_read,
+ all_module_statics,
+ node_g->statics_read);
+ }
+
+ if (bitmap_empty_p (node_g->statics_written))
+ opt->statics_not_written = all_module_statics;
+ else
+ {
+ opt->statics_not_written
+ = BITMAP_ALLOC (&optimization_summary_obstack);
+ if (node_g->statics_written != all_module_statics)
+ bitmap_and_compl (opt->statics_not_written,
+ all_module_statics,
+ node_g->statics_written);
+ }
+ }
+ free (node_info);
}
+ ipa_free_postorder_info ();
free (order);
- for (node = cgraph_nodes; node; node = node->next)
+ bitmap_obstack_release (&local_info_obstack);
+ VEC_free (ipa_reference_vars_info_t, heap, ipa_reference_vars_vector);
+ ipa_reference_vars_vector = NULL;
+ if (dump_file)
+ splay_tree_delete (reference_vars_to_consider);
+ reference_vars_to_consider = NULL;
+ return 0;
+}
+
+/* Return true if we need to write summary of NODE. */
+
+static bool
+write_node_summary_p (struct cgraph_node *node,
+ cgraph_node_set set,
+ varpool_node_set vset,
+ bitmap ltrans_statics)
+{
+ ipa_reference_optimization_summary_t info;
+
+ /* See if we have (non-empty) info. */
+ if (!node->analyzed || node->global.inlined_to)
+ return false;
+ info = get_reference_optimization_summary (node);
+ if (!info || (bitmap_empty_p (info->statics_not_read)
+ && bitmap_empty_p (info->statics_not_written)))
+ return false;
+
+ /* See if we want to encode it.
+ Encode also referenced functions since constant folding might turn it into
+ a direct call.
+
+ In future we might also want to include summaries of functions references
+ by initializers of constant variables references in current unit. */
+ if (!reachable_from_this_partition_p (node, set)
+ && !referenced_from_this_partition_p (&node->ref_list, set, vset))
+ return false;
+
+ /* See if the info has non-empty intersections with vars we want to encode. */
+ if (!bitmap_intersect_p (info->statics_not_read, ltrans_statics)
+ && !bitmap_intersect_p (info->statics_not_written, ltrans_statics))
+ return false;
+ return true;
+}
+
+/* Stream out BITS<RANS_STATICS as list of decls to OB.
+ LTRANS_STATICS_BITCOUNT specify number of bits in LTRANS_STATICS
+ or -1. When it is positive, just output -1 when
+ BITS<RANS_STATICS == BITS<RANS_STATICS. */
+
+static void
+stream_out_bitmap (struct lto_simple_output_block *ob,
+ bitmap bits, bitmap ltrans_statics,
+ int ltrans_statics_bitcount)
+{
+ int count = 0;
+ unsigned int index;
+ bitmap_iterator bi;
+ if (bits == all_module_statics)
+ {
+ streamer_write_hwi_stream (ob->main_stream, -1);
+ return;
+ }
+ EXECUTE_IF_AND_IN_BITMAP (bits, ltrans_statics, 0, index, bi)
+ count ++;
+ if (count == ltrans_statics_bitcount)
+ {
+ streamer_write_hwi_stream (ob->main_stream, -1);
+ return;
+ }
+ streamer_write_hwi_stream (ob->main_stream, count);
+ if (!count)
+ return;
+ EXECUTE_IF_AND_IN_BITMAP (bits, ltrans_statics, 0, index, bi)
+ {
+ tree decl = (tree)splay_tree_lookup (reference_vars_to_consider, index)->value;
+ lto_output_var_decl_index(ob->decl_state, ob->main_stream, decl);
+ }
+}
+
+/* Serialize the ipa info for lto. */
+
+static void
+ipa_reference_write_optimization_summary (cgraph_node_set set,
+ varpool_node_set vset)
+{
+ struct cgraph_node *node;
+ struct lto_simple_output_block *ob
+ = lto_create_simple_output_block (LTO_section_ipa_reference);
+ unsigned int count = 0;
+ int ltrans_statics_bitcount = 0;
+ lto_cgraph_encoder_t encoder = ob->decl_state->cgraph_node_encoder;
+ lto_varpool_encoder_t varpool_encoder = ob->decl_state->varpool_node_encoder;
+ bitmap ltrans_statics = BITMAP_ALLOC (NULL);
+ int i;
+
+ reference_vars_to_consider = splay_tree_new (splay_tree_compare_ints, 0, 0);
+
+ /* See what variables we are interested in. */
+ for (i = 0; i < lto_varpool_encoder_size (varpool_encoder); i++)
{
- /* Get rid of the aux information. */
-
- if (node->aux)
+ struct varpool_node *vnode = lto_varpool_encoder_deref (varpool_encoder, i);
+ if (!vnode->externally_visible
+ && vnode->analyzed
+ && bitmap_bit_p (all_module_statics, DECL_UID (vnode->decl))
+ && referenced_from_this_partition_p (&vnode->ref_list, set, vset))
{
- free (node->aux);
- node->aux = NULL;
+ tree decl = vnode->decl;
+ bitmap_set_bit (ltrans_statics, DECL_UID (decl));
+ splay_tree_insert (reference_vars_to_consider,
+ DECL_UID (decl), (splay_tree_value)decl);
+ ltrans_statics_bitcount ++;
}
-
- if (node->analyzed
- && (cgraph_function_body_availability (node) == AVAIL_OVERWRITABLE))
- clean_function (node);
}
- return 0;
+
+
+ if (ltrans_statics_bitcount)
+ for (i = 0; i < lto_cgraph_encoder_size (encoder); i++)
+ if (write_node_summary_p (lto_cgraph_encoder_deref (encoder, i),
+ set, vset, ltrans_statics))
+ count++;
+
+ streamer_write_uhwi_stream (ob->main_stream, count);
+ if (count)
+ stream_out_bitmap (ob, ltrans_statics, ltrans_statics,
+ -1);
+
+ /* Process all of the functions. */
+ if (ltrans_statics_bitcount)
+ for (i = 0; i < lto_cgraph_encoder_size (encoder); i++)
+ {
+ node = lto_cgraph_encoder_deref (encoder, i);
+ if (write_node_summary_p (node, set, vset, ltrans_statics))
+ {
+ ipa_reference_optimization_summary_t info;
+ int node_ref;
+
+ info = get_reference_optimization_summary (node);
+ node_ref = lto_cgraph_encoder_encode (encoder, node);
+ streamer_write_uhwi_stream (ob->main_stream, node_ref);
+
+ stream_out_bitmap (ob, info->statics_not_read, ltrans_statics,
+ ltrans_statics_bitcount);
+ stream_out_bitmap (ob, info->statics_not_written, ltrans_statics,
+ ltrans_statics_bitcount);
+ }
+ }
+ BITMAP_FREE (ltrans_statics);
+ lto_destroy_simple_output_block (ob);
+ splay_tree_delete (reference_vars_to_consider);
}
+/* Deserialize the ipa info for lto. */
+
+static void
+ipa_reference_read_optimization_summary (void)
+{
+ struct lto_file_decl_data ** file_data_vec
+ = lto_get_file_decl_data ();
+ struct lto_file_decl_data * file_data;
+ unsigned int j = 0;
+ bitmap_obstack_initialize (&optimization_summary_obstack);
+
+ node_removal_hook_holder =
+ cgraph_add_node_removal_hook (&remove_node_data, NULL);
+ node_duplication_hook_holder =
+ cgraph_add_node_duplication_hook (&duplicate_node_data, NULL);
+ all_module_statics = BITMAP_ALLOC (&optimization_summary_obstack);
+
+ while ((file_data = file_data_vec[j++]))
+ {
+ const char *data;
+ size_t len;
+ struct lto_input_block *ib
+ = lto_create_simple_input_block (file_data,
+ LTO_section_ipa_reference,
+ &data, &len);
+ if (ib)
+ {
+ unsigned int i;
+ unsigned int f_count = streamer_read_uhwi (ib);
+ int b_count;
+ if (!f_count)
+ continue;
+ b_count = streamer_read_hwi (ib);
+ if (dump_file)
+ fprintf (dump_file, "all module statics:");
+ for (i = 0; i < (unsigned int)b_count; i++)
+ {
+ unsigned int var_index = streamer_read_uhwi (ib);
+ tree v_decl = lto_file_decl_data_get_var_decl (file_data,
+ var_index);
+ bitmap_set_bit (all_module_statics, DECL_UID (v_decl));
+ if (dump_file)
+ fprintf (dump_file, " %s",
+ lang_hooks.decl_printable_name (v_decl, 2));
+ }
+
+ for (i = 0; i < f_count; i++)
+ {
+ unsigned int j, index;
+ struct cgraph_node *node;
+ ipa_reference_optimization_summary_t info;
+ int v_count;
+ lto_cgraph_encoder_t encoder;
+
+ index = streamer_read_uhwi (ib);
+ encoder = file_data->cgraph_node_encoder;
+ node = lto_cgraph_encoder_deref (encoder, index);
+ info = XCNEW (struct ipa_reference_optimization_summary_d);
+ set_reference_optimization_summary (node, info);
+ info->statics_not_read = BITMAP_ALLOC (&optimization_summary_obstack);
+ info->statics_not_written = BITMAP_ALLOC (&optimization_summary_obstack);
+ if (dump_file)
+ fprintf (dump_file,
+ "\nFunction name:%s/%i:\n static not read:",
+ cgraph_node_name (node), node->uid);
+
+ /* Set the statics not read. */
+ v_count = streamer_read_hwi (ib);
+ if (v_count == -1)
+ {
+ info->statics_not_read = all_module_statics;
+ if (dump_file)
+ fprintf (dump_file, " all module statics");
+ }
+ else
+ for (j = 0; j < (unsigned int)v_count; j++)
+ {
+ unsigned int var_index = streamer_read_uhwi (ib);
+ tree v_decl = lto_file_decl_data_get_var_decl (file_data,
+ var_index);
+ bitmap_set_bit (info->statics_not_read, DECL_UID (v_decl));
+ if (dump_file)
+ fprintf (dump_file, " %s",
+ lang_hooks.decl_printable_name (v_decl, 2));
+ }
+
+ if (dump_file)
+ fprintf (dump_file,
+ "\n static not written:");
+ /* Set the statics not written. */
+ v_count = streamer_read_hwi (ib);
+ if (v_count == -1)
+ {
+ info->statics_not_written = all_module_statics;
+ if (dump_file)
+ fprintf (dump_file, " all module statics");
+ }
+ else
+ for (j = 0; j < (unsigned int)v_count; j++)
+ {
+ unsigned int var_index = streamer_read_uhwi (ib);
+ tree v_decl = lto_file_decl_data_get_var_decl (file_data,
+ var_index);
+ bitmap_set_bit (info->statics_not_written, DECL_UID (v_decl));
+ if (dump_file)
+ fprintf (dump_file, " %s",
+ lang_hooks.decl_printable_name (v_decl, 2));
+ }
+ if (dump_file)
+ fprintf (dump_file, "\n");
+ }
+
+ lto_destroy_simple_input_block (file_data,
+ LTO_section_ipa_reference,
+ ib, data, len);
+ }
+ else
+ /* Fatal error here. We do not want to support compiling ltrans units with
+ different version of compiler or different flags than the WPA unit, so
+ this should never happen. */
+ fatal_error ("ipa reference summary is missing in ltrans unit");
+ }
+}
static bool
gate_reference (void)
{
return (flag_ipa_reference
/* Don't bother doing anything if the program has errors. */
- && !(errorcount || sorrycount));
+ && !seen_error ());
}
-struct simple_ipa_opt_pass pass_ipa_reference =
+struct ipa_opt_pass_d pass_ipa_reference =
{
{
- SIMPLE_IPA_PASS,
+ IPA_PASS,
"static-var", /* name */
gate_reference, /* gate */
- static_execute, /* execute */
+ propagate, /* execute */
NULL, /* sub */
NULL, /* next */
0, /* static_pass_number */
0, /* properties_destroyed */
0, /* todo_flags_start */
0 /* todo_flags_finish */
- }
+ },
+ NULL, /* generate_summary */
+ NULL, /* write_summary */
+ NULL, /* read_summary */
+ ipa_reference_write_optimization_summary,/* write_optimization_summary */
+ ipa_reference_read_optimization_summary,/* read_optimization_summary */
+ NULL, /* stmt_fixup */
+ 0, /* TODOs */
+ NULL, /* function_transform */
+ NULL /* variable_transform */
};
-
-#include "gt-ipa-reference.h"
-
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