/* Interprocedural constant propagation
- Copyright (C) 2005, 2006, 2007, 2008 Free Software Foundation, Inc.
+ Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010
+ Free Software Foundation, Inc.
Contributed by Razya Ladelsky <RAZYA@il.ibm.com>
-
+
This file is part of GCC.
-
+
GCC is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 3, or (at your option) any later
version.
-
+
GCC is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.
-
+
You should have received a copy of the GNU General Public License
along with GCC; see the file COPYING3. If not see
<http://www.gnu.org/licenses/>. */
{
printf ("value is %d",y);
}
-
+
int f (int x)
{
g (x);
f (3);
h (3);
}
-
-
+
+
The IPCP algorithm will find that g's formal argument y is always called
with the value 3.
The algorithm used is based on "Interprocedural Constant Propagation", by
Challahan David, Keith D Cooper, Ken Kennedy, Linda Torczon, Comp86, pg
152-161
-
+
The optimization is divided into three stages:
First stage - intraprocedural analysis
=======================================
This phase computes jump_function and modification flags.
-
+
A jump function for a callsite represents the values passed as an actual
arguments of a given callsite. There are three types of values:
Pass through - the caller's formal parameter is passed as an actual argument.
Constant - a constant is passed as an actual argument.
Unknown - neither of the above.
-
+
The jump function info, ipa_jump_func, is stored in ipa_edge_args
structure (defined in ipa_prop.h and pointed to by cgraph_node->aux)
modified_flags are defined in ipa_node_params structure
(defined in ipa_prop.h and pointed to by cgraph_edge->aux).
-
- -ipcp_init_stage() is the first stage driver.
+
+ -ipcp_generate_summary() is the first stage driver.
Second stage - interprocedural analysis
========================================
TOP - unknown.
BOTTOM - non constant.
CONSTANT - constant value.
-
+
Lattice describing a formal parameter p will have a constant value if all
callsites invoking this function have the same constant value passed to p.
-
+
The lattices are stored in ipcp_lattice which is itself in ipa_node_params
structure (defined in ipa_prop.h and pointed to by cgraph_edge->aux).
2. For read-only parameters that do not live in memory, we replace all their
uses with the constant.
- We also need to modify some callsites to call the cloned functiosns instead
+ We also need to modify some callsites to call the cloned functions instead
of the original ones. For a callsite passing an argument found to be a
constant by IPCP, there are two different cases to handle:
1. A constant is passed as an argument. In this case the callsite in the
only the callsite in the cloned caller is redirected to call to the
cloned callee.
- This update is done in two steps: First all cloned functionss are created
+ This update is done in two steps: First all cloned functions are created
during a traversal of the call graph, during which all callsites are
redirected to call the cloned function. Then the callsites are traversed
and many calls redirected back to fit the description above.
-ipcp_insert_stage() is the third phase driver.
-
+
+
+ This pass also performs devirtualization - turns virtual calls into direct
+ ones if it can prove that all invocations of the function call the same
+ callee. This is achieved by building a list of all base types (actually,
+ their BINFOs) that individual parameters can have in an iterative matter
+ just like propagating scalar constants and then examining whether virtual
+ calls which take a parameter as their object fold to the same target for all
+ these types. If we cannot enumerate all types or there is a type which does
+ not have any BINFO associated with it, cannot_devirtualize of the associated
+ parameter descriptor is set which is an equivalent of BOTTOM lattice value
+ in standard IPA constant propagation.
*/
#include "config.h"
#include "coretypes.h"
#include "tree.h"
#include "target.h"
+#include "gimple.h"
#include "cgraph.h"
#include "ipa-prop.h"
#include "tree-flow.h"
#include "flags.h"
#include "timevar.h"
#include "diagnostic.h"
+#include "tree-pretty-print.h"
#include "tree-dump.h"
#include "tree-inline.h"
+#include "fibheap.h"
+#include "params.h"
+
+/* Number of functions identified as candidates for cloning. When not cloning
+ we can simplify iterate stage not forcing it to go through the decision
+ on what is profitable and what not. */
+static int n_cloning_candidates;
+
+/* Maximal count found in program. */
+static gcov_type max_count;
+
+/* Cgraph nodes that has been completely replaced by cloning during iterate
+ * stage and will be removed after ipcp is finished. */
+static bitmap dead_nodes;
+
+static void ipcp_print_profile_data (FILE *);
+static void ipcp_function_scale_print (FILE *);
/* Get the original node field of ipa_node_params associated with node NODE. */
static inline struct cgraph_node *
ipcp_init_cloned_node (struct cgraph_node *orig_node,
struct cgraph_node *new_node)
{
- ipa_create_node_params (new_node);
+ gcc_checking_assert (ipa_node_params_vector
+ && (VEC_length (ipa_node_params_t,
+ ipa_node_params_vector)
+ > (unsigned) cgraph_max_uid));
+ gcc_checking_assert (IPA_NODE_REF (new_node)->params);
IPA_NODE_REF (new_node)->ipcp_orig_node = orig_node;
- ipa_count_formal_params (new_node);
- ipa_create_param_decls_array (new_node);
}
/* Return scale for NODE. */
static inline bool
ipcp_lat_is_const (struct ipcp_lattice *lat)
{
- if (lat->type == IPA_CONST_VALUE || lat->type == IPA_CONST_VALUE_REF)
+ if (lat->type == IPA_CONST_VALUE)
return true;
else
return false;
}
+/* Return whether LAT is a constant lattice that ipa-cp can actually insert
+ into the code (i.e. constants excluding member pointers and pointers). */
+static inline bool
+ipcp_lat_is_insertable (struct ipcp_lattice *lat)
+{
+ return lat->type == IPA_CONST_VALUE;
+}
+
/* Return true if LAT1 and LAT2 are equal. */
static inline bool
ipcp_lats_are_equal (struct ipcp_lattice *lat1, struct ipcp_lattice *lat2)
if (lat1->type != lat2->type)
return false;
- if (operand_equal_p (lat1->constant, lat2->constant, 0))
- return true;
-
- return false;
+ if (TREE_CODE (lat1->constant) == ADDR_EXPR
+ && TREE_CODE (lat2->constant) == ADDR_EXPR
+ && TREE_CODE (TREE_OPERAND (lat1->constant, 0)) == CONST_DECL
+ && TREE_CODE (TREE_OPERAND (lat2->constant, 0)) == CONST_DECL)
+ return operand_equal_p (DECL_INITIAL (TREE_OPERAND (lat1->constant, 0)),
+ DECL_INITIAL (TREE_OPERAND (lat2->constant, 0)), 0);
+ else
+ return operand_equal_p (lat1->constant, lat2->constant, 0);
}
/* Compute Meet arithmetics:
/* Return the lattice corresponding to the Ith formal parameter of the function
described by INFO. */
static inline struct ipcp_lattice *
-ipcp_get_ith_lattice (struct ipa_node_params *info, int i)
+ipcp_get_lattice (struct ipa_node_params *info, int i)
{
- return &(info->ipcp_lattices[i]);
+ return &(info->params[i].ipcp_lattice);
}
/* Given the jump function JFUNC, compute the lattice LAT that describes the
ipcp_lattice_from_jfunc (struct ipa_node_params *info, struct ipcp_lattice *lat,
struct ipa_jump_func *jfunc)
{
- if (jfunc->type == IPA_UNKNOWN)
- lat->type = IPA_BOTTOM;
- else if (jfunc->type == IPA_CONST)
+ if (jfunc->type == IPA_JF_CONST)
{
lat->type = IPA_CONST_VALUE;
lat->constant = jfunc->value.constant;
}
- else if (jfunc->type == IPA_CONST_REF)
+ else if (jfunc->type == IPA_JF_PASS_THROUGH)
{
- lat->type = IPA_CONST_VALUE_REF;
- lat->constant = jfunc->value.constant;
+ struct ipcp_lattice *caller_lat;
+ tree cst;
+
+ caller_lat = ipcp_get_lattice (info, jfunc->value.pass_through.formal_id);
+ lat->type = caller_lat->type;
+ if (caller_lat->type != IPA_CONST_VALUE)
+ return;
+ cst = caller_lat->constant;
+
+ if (jfunc->value.pass_through.operation != NOP_EXPR)
+ {
+ tree restype;
+ if (TREE_CODE_CLASS (jfunc->value.pass_through.operation)
+ == tcc_comparison)
+ restype = boolean_type_node;
+ else
+ restype = TREE_TYPE (cst);
+ cst = fold_binary (jfunc->value.pass_through.operation,
+ restype, cst, jfunc->value.pass_through.operand);
+ }
+ if (!cst || !is_gimple_ip_invariant (cst))
+ lat->type = IPA_BOTTOM;
+ lat->constant = cst;
}
- else if (jfunc->type == IPA_PASS_THROUGH)
+ else if (jfunc->type == IPA_JF_ANCESTOR)
{
struct ipcp_lattice *caller_lat;
+ tree t;
+ bool ok;
- caller_lat = ipcp_get_ith_lattice (info, jfunc->value.formal_id);
+ caller_lat = ipcp_get_lattice (info, jfunc->value.ancestor.formal_id);
lat->type = caller_lat->type;
- lat->constant = caller_lat->constant;
+ if (caller_lat->type != IPA_CONST_VALUE)
+ return;
+ if (TREE_CODE (caller_lat->constant) != ADDR_EXPR)
+ {
+ /* This can happen when the constant is a NULL pointer. */
+ lat->type = IPA_BOTTOM;
+ return;
+ }
+ t = TREE_OPERAND (caller_lat->constant, 0);
+ ok = build_ref_for_offset (&t, TREE_TYPE (t),
+ jfunc->value.ancestor.offset,
+ jfunc->value.ancestor.type, false);
+ if (!ok)
+ {
+ lat->type = IPA_BOTTOM;
+ lat->constant = NULL_TREE;
+ }
+ else
+ lat->constant = build_fold_addr_expr (t);
}
+ else
+ lat->type = IPA_BOTTOM;
}
-/* True when OLD and NEW values are not the same. */
+/* True when OLD_LAT and NEW_LAT values are not the same. */
+
static bool
-ipcp_lattice_changed (struct ipcp_lattice *old, struct ipcp_lattice *new)
+ipcp_lattice_changed (struct ipcp_lattice *old_lat,
+ struct ipcp_lattice *new_lat)
{
- if (old->type == new->type)
+ if (old_lat->type == new_lat->type)
{
- if (!ipcp_lat_is_const (old))
+ if (!ipcp_lat_is_const (old_lat))
return false;
- if (ipcp_lats_are_equal (old, new))
+ if (ipcp_lats_are_equal (old_lat, new_lat))
return false;
}
return true;
struct cgraph_node *node;
int i, count;
- fprintf (f, "\nLATTICE PRINT\n");
+ fprintf (f, "\nLattice:\n");
for (node = cgraph_nodes; node; node = node->next)
{
- struct ipa_node_params *info = IPA_NODE_REF (node);
- fprintf (f, "Printing lattices %s:\n", cgraph_node_name (node));
+ struct ipa_node_params *info;
+
+ if (!node->analyzed)
+ continue;
+ info = IPA_NODE_REF (node);
+ fprintf (f, " Node: %s:\n", cgraph_node_name (node));
count = ipa_get_param_count (info);
for (i = 0; i < count; i++)
{
- struct ipcp_lattice *lat = ipcp_get_ith_lattice (info, i);
- if (lat->type == IPA_CONST_VALUE || lat->type == IPA_CONST_VALUE_REF)
+ struct ipcp_lattice *lat = ipcp_get_lattice (info, i);
+
+ fprintf (f, " param [%d]: ", i);
+ if (lat->type == IPA_CONST_VALUE)
{
- fprintf (f, " param [%d]: ", i);
+ tree cst = lat->constant;
fprintf (f, "type is CONST ");
- print_generic_expr (f, lat->constant, 0);
- fprintf (f, "\n");
+ print_generic_expr (f, cst, 0);
+ if (TREE_CODE (cst) == ADDR_EXPR
+ && TREE_CODE (TREE_OPERAND (cst, 0)) == CONST_DECL)
+ {
+ fprintf (f, " -> ");
+ print_generic_expr (f, DECL_INITIAL (TREE_OPERAND (cst, 0)),
+ 0);
+ }
}
else if (lat->type == IPA_TOP)
- fprintf (f, "param [%d]: type is TOP \n", i);
+ fprintf (f, "type is TOP");
+ else
+ fprintf (f, "type is BOTTOM");
+ if (ipa_param_cannot_devirtualize_p (info, i))
+ fprintf (f, " - cannot_devirtualize set\n");
+ else if (ipa_param_types_vec_empty (info, i))
+ fprintf (f, " - type list empty\n");
else
- fprintf (f, "param [%d]: type is BOTTOM \n", i);
+ fprintf (f, "\n");
}
}
}
-/* Initialize ipcp_lattices array. The lattices corresponding to supported
- types (integers, real types and Fortran constants defined as const_decls)
- are initialized to IPA_TOP, the rest of them to IPA_BOTTOM. */
-static void
-ipcp_initialize_node_lattices (struct cgraph_node *node)
+/* Return true if ipcp algorithms would allow cloning NODE. */
+
+static bool
+ipcp_versionable_function_p (struct cgraph_node *node)
{
- int i;
- struct ipa_node_params *info = IPA_NODE_REF (node);
+ struct cgraph_edge *edge;
- info->ipcp_lattices = XCNEWVEC (struct ipcp_lattice,
- ipa_get_param_count (info));
- for (i = 0; i < ipa_get_param_count (info) ; i++)
+ /* There are a number of generic reasons functions cannot be versioned. */
+ if (!node->local.versionable)
+ return false;
+
+ /* Removing arguments doesn't work if the function takes varargs
+ or use __builtin_apply_args. */
+ for (edge = node->callees; edge; edge = edge->next_callee)
{
- tree parm_tree = ipa_get_ith_param (info, i);
- struct ipcp_lattice *lat = ipcp_get_ith_lattice (info, i);
+ tree t = edge->callee->decl;
+ if (DECL_BUILT_IN_CLASS (t) == BUILT_IN_NORMAL
+ && (DECL_FUNCTION_CODE (t) == BUILT_IN_APPLY_ARGS
+ || DECL_FUNCTION_CODE (t) == BUILT_IN_VA_START))
+ return false;
+ }
- if (INTEGRAL_TYPE_P (TREE_TYPE (parm_tree))
- || SCALAR_FLOAT_TYPE_P (TREE_TYPE (parm_tree))
- || POINTER_TYPE_P (TREE_TYPE (parm_tree)))
- lat->type = IPA_TOP;
- else
- lat->type = IPA_BOTTOM;
+ return true;
+}
+
+/* Return true if this NODE is viable candidate for cloning. */
+static bool
+ipcp_cloning_candidate_p (struct cgraph_node *node)
+{
+ int n_calls = 0;
+ int n_hot_calls = 0;
+ gcov_type direct_call_sum = 0;
+ struct cgraph_edge *e;
+
+ /* We never clone functions that are not visible from outside.
+ FIXME: in future we should clone such functions when they are called with
+ different constants, but current ipcp implementation is not good on this.
+ */
+ if (cgraph_only_called_directly_p (node) || !node->analyzed)
+ return false;
+
+ if (cgraph_function_body_availability (node) <= AVAIL_OVERWRITABLE)
+ {
+ if (dump_file)
+ fprintf (dump_file, "Not considering %s for cloning; body is overwrittable.\n",
+ cgraph_node_name (node));
+ return false;
}
+ if (!ipcp_versionable_function_p (node))
+ {
+ if (dump_file)
+ fprintf (dump_file, "Not considering %s for cloning; body is not versionable.\n",
+ cgraph_node_name (node));
+ return false;
+ }
+ for (e = node->callers; e; e = e->next_caller)
+ {
+ direct_call_sum += e->count;
+ n_calls ++;
+ if (cgraph_maybe_hot_edge_p (e))
+ n_hot_calls ++;
+ }
+
+ if (!n_calls)
+ {
+ if (dump_file)
+ fprintf (dump_file, "Not considering %s for cloning; no direct calls.\n",
+ cgraph_node_name (node));
+ return false;
+ }
+ if (node->local.inline_summary.self_size < n_calls)
+ {
+ if (dump_file)
+ fprintf (dump_file, "Considering %s for cloning; code would shrink.\n",
+ cgraph_node_name (node));
+ return true;
+ }
+
+ if (!flag_ipa_cp_clone)
+ {
+ if (dump_file)
+ fprintf (dump_file, "Not considering %s for cloning; -fipa-cp-clone disabled.\n",
+ cgraph_node_name (node));
+ return false;
+ }
+
+ if (!optimize_function_for_speed_p (DECL_STRUCT_FUNCTION (node->decl)))
+ {
+ if (dump_file)
+ fprintf (dump_file, "Not considering %s for cloning; optimizing it for size.\n",
+ cgraph_node_name (node));
+ return false;
+ }
+
+ /* When profile is available and function is hot, propagate into it even if
+ calls seems cold; constant propagation can improve function's speed
+ significandly. */
+ if (max_count)
+ {
+ if (direct_call_sum > node->count * 90 / 100)
+ {
+ if (dump_file)
+ fprintf (dump_file, "Considering %s for cloning; usually called directly.\n",
+ cgraph_node_name (node));
+ return true;
+ }
+ }
+ if (!n_hot_calls)
+ {
+ if (dump_file)
+ fprintf (dump_file, "Not considering %s for cloning; no hot calls.\n",
+ cgraph_node_name (node));
+ return false;
+ }
+ if (dump_file)
+ fprintf (dump_file, "Considering %s for cloning.\n",
+ cgraph_node_name (node));
+ return true;
}
-/* Create a new assignment statement and make it the first statement in the
- function. PARM1 is the lhs of the assignment and VAL is the rhs. */
-static void
-constant_val_insert (tree parm1, tree val)
+/* Mark parameter with index I of function described by INFO as unsuitable for
+ devirtualization. Return true if it has already been marked so. */
+
+static bool
+ipa_set_param_cannot_devirtualize (struct ipa_node_params *info, int i)
{
- tree init_stmt = NULL;
- edge e_step;
+ bool ret = info->params[i].cannot_devirtualize;
+ info->params[i].cannot_devirtualize = true;
+ if (info->params[i].types)
+ VEC_free (tree, heap, info->params[i].types);
+ return ret;
+}
- init_stmt = build_gimple_modify_stmt (parm1, val);
+/* Initialize ipcp_lattices array. The lattices corresponding to supported
+ types (integers, real types and Fortran constants defined as const_decls)
+ are initialized to IPA_TOP, the rest of them to IPA_BOTTOM. */
+static void
+ipcp_initialize_node_lattices (struct cgraph_node *node)
+{
+ int i;
+ struct ipa_node_params *info = IPA_NODE_REF (node);
+ enum ipa_lattice_type type;
+
+ if (ipa_is_called_with_var_arguments (info))
+ type = IPA_BOTTOM;
+ else if (cgraph_only_called_directly_p (node))
+ type = IPA_TOP;
+ /* When cloning is allowed, we can assume that externally visible functions
+ are not called. We will compensate this by cloning later. */
+ else if (ipcp_cloning_candidate_p (node))
+ type = IPA_TOP, n_cloning_candidates ++;
+ else
+ type = IPA_BOTTOM;
- if (init_stmt)
+ for (i = 0; i < ipa_get_param_count (info) ; i++)
{
- e_step = single_succ_edge (ENTRY_BLOCK_PTR_FOR_FUNCTION (cfun));
- bsi_insert_on_edge_immediate (e_step, init_stmt);
+ ipcp_get_lattice (info, i)->type = type;
+ if (type == IPA_BOTTOM)
+ ipa_set_param_cannot_devirtualize (info, i);
}
}
static tree
build_const_val (struct ipcp_lattice *lat, tree tree_type)
{
- tree const_val = NULL;
+ tree val;
gcc_assert (ipcp_lat_is_const (lat));
- const_val = fold_convert (tree_type, lat->constant);
- return const_val;
-}
+ val = lat->constant;
-/* Build the tree representing the constant and call constant_val_insert(). */
-static void
-ipcp_propagate_one_const (struct cgraph_node *node, int param,
- struct ipcp_lattice *lat)
-{
- tree const_val;
- tree parm_tree;
-
- if (dump_file)
- fprintf (dump_file, "propagating const to %s\n", cgraph_node_name (node));
- parm_tree = ipa_get_ith_param (IPA_NODE_REF (node), param);
- const_val = build_const_val (lat, TREE_TYPE (parm_tree));
- constant_val_insert (parm_tree, const_val);
+ if (!useless_type_conversion_p (tree_type, TREE_TYPE (val)))
+ {
+ if (fold_convertible_p (tree_type, val))
+ return fold_build1 (NOP_EXPR, tree_type, val);
+ else
+ return fold_build1 (VIEW_CONVERT_EXPR, tree_type, val);
+ }
+ return val;
}
/* Compute the proper scale for NODE. It is the ratio between the number of
direct calls (represented on the incoming cgraph_edges) and sum of all
- invocations of NODE (represented as count in cgraph_node). */
+ invocations of NODE (represented as count in cgraph_node).
+
+ FIXME: This code is wrong. Since the callers can be also clones and
+ the clones are not scaled yet, the sums gets unrealistically high.
+ To properly compute the counts, we would need to do propagation across
+ callgraph (as external call to A might imply call to non-clonned B
+ if A's clone calls clonned B). */
static void
ipcp_compute_node_scale (struct cgraph_node *node)
{
/* Compute sum of all counts of callers. */
for (cs = node->callers; cs != NULL; cs = cs->next_caller)
sum += cs->count;
+ /* Work around the unrealistically high sum problem. We just don't want
+ the non-cloned body to have negative or very low frequency. Since
+ majority of execution time will be spent in clones anyway, this should
+ give good enough profile. */
+ if (sum > node->count * 9 / 10)
+ sum = node->count * 9 / 10;
if (node->count == 0)
ipcp_set_node_scale (node, 0);
else
ipcp_set_node_scale (node, sum * REG_BR_PROB_BASE / node->count);
}
-/* Initialization and computation of IPCP data structures. This is the initial
- intraprocedural analysis of functions, which gathers information to be
- propagated later on. */
-static void
-ipcp_init_stage (void)
-{
- struct cgraph_node *node;
- struct cgraph_edge *cs;
-
- for (node = cgraph_nodes; node; node = node->next)
- {
- ipa_count_formal_params (node);
- ipa_create_param_decls_array (node);
- ipcp_initialize_node_lattices (node);
- ipa_detect_param_modifications (node);
- ipcp_compute_node_scale (node);
- }
- for (node = cgraph_nodes; node; node = node->next)
- {
- /* building jump functions */
- for (cs = node->callees; cs; cs = cs->next_callee)
- {
- ipa_count_arguments (cs);
- if (ipa_get_cs_argument_count (IPA_EDGE_REF (cs))
- != ipa_get_param_count (IPA_NODE_REF (cs->callee)))
- {
- /* Handle cases of functions with
- a variable number of parameters. */
- ipa_set_called_with_variable_arg (IPA_NODE_REF (cs->callee));
- }
- else
- ipa_compute_jump_functions (cs);
- }
- }
-}
-
/* Return true if there are some formal parameters whose value is IPA_TOP (in
the whole compilation unit). Change their values to IPA_BOTTOM, since they
most probably get their values from outside of this compilation unit. */
count = ipa_get_param_count (info);
for (i = 0; i < count; i++)
{
- struct ipcp_lattice *lat = ipcp_get_ith_lattice (info, i);
+ struct ipcp_lattice *lat = ipcp_get_lattice (info, i);
if (lat->type == IPA_TOP)
{
prop_again = true;
+ if (dump_file)
+ {
+ fprintf (dump_file, "Forcing param ");
+ print_generic_expr (dump_file, ipa_get_param (info, i), 0);
+ fprintf (dump_file, " of node %s to bottom.\n",
+ cgraph_node_name (node));
+ }
lat->type = IPA_BOTTOM;
}
+ if (!ipa_param_cannot_devirtualize_p (info, i)
+ && ipa_param_types_vec_empty (info, i))
+ {
+ prop_again = true;
+ ipa_set_param_cannot_devirtualize (info, i);
+ if (dump_file)
+ {
+ fprintf (dump_file, "Marking param ");
+ print_generic_expr (dump_file, ipa_get_param (info, i), 0);
+ fprintf (dump_file, " of node %s as unusable for "
+ "devirtualization.\n",
+ cgraph_node_name (node));
+ }
+ }
}
}
return prop_again;
}
+/* Insert BINFO to the list of known types of parameter number I of the
+ function described by CALLEE_INFO. Return true iff the type information
+ associated with the callee parameter changed in any way. */
+
+static bool
+ipcp_add_param_type (struct ipa_node_params *callee_info, int i, tree binfo)
+{
+ int j, count;
+
+ if (ipa_param_cannot_devirtualize_p (callee_info, i))
+ return false;
+
+ if (callee_info->params[i].types)
+ {
+ count = VEC_length (tree, callee_info->params[i].types);
+ for (j = 0; j < count; j++)
+ if (VEC_index (tree, callee_info->params[i].types, j) == binfo)
+ return false;
+ }
+
+ if (VEC_length (tree, callee_info->params[i].types)
+ == (unsigned) PARAM_VALUE (PARAM_DEVIRT_TYPE_LIST_SIZE))
+ return !ipa_set_param_cannot_devirtualize (callee_info, i);
+
+ VEC_safe_push (tree, heap, callee_info->params[i].types, binfo);
+ return true;
+}
+
+/* Copy known types information for parameter number CALLEE_IDX of CALLEE_INFO
+ from a parameter of CALLER_INFO as described by JF. Return true iff the
+ type information changed in any way. JF must be a pass-through or an
+ ancestor jump function. */
+
+static bool
+ipcp_copy_types (struct ipa_node_params *caller_info,
+ struct ipa_node_params *callee_info,
+ int callee_idx, struct ipa_jump_func *jf)
+{
+ int caller_idx, j, count;
+ bool res;
+
+ if (ipa_param_cannot_devirtualize_p (callee_info, callee_idx))
+ return false;
+
+ if (jf->type == IPA_JF_PASS_THROUGH)
+ {
+ if (jf->value.pass_through.operation != NOP_EXPR)
+ {
+ ipa_set_param_cannot_devirtualize (callee_info, callee_idx);
+ return true;
+ }
+ caller_idx = jf->value.pass_through.formal_id;
+ }
+ else
+ caller_idx = jf->value.ancestor.formal_id;
+
+ if (ipa_param_cannot_devirtualize_p (caller_info, caller_idx))
+ {
+ ipa_set_param_cannot_devirtualize (callee_info, callee_idx);
+ return true;
+ }
+
+ if (!caller_info->params[caller_idx].types)
+ return false;
+
+ res = false;
+ count = VEC_length (tree, caller_info->params[caller_idx].types);
+ for (j = 0; j < count; j++)
+ {
+ tree binfo = VEC_index (tree, caller_info->params[caller_idx].types, j);
+ if (jf->type == IPA_JF_ANCESTOR)
+ {
+ binfo = get_binfo_at_offset (binfo, jf->value.ancestor.offset,
+ jf->value.ancestor.type);
+ if (!binfo)
+ {
+ ipa_set_param_cannot_devirtualize (callee_info, callee_idx);
+ return true;
+ }
+ }
+ res |= ipcp_add_param_type (callee_info, callee_idx, binfo);
+ }
+ return res;
+}
+
+/* Propagate type information for parameter of CALLEE_INFO number I as
+ described by JF. CALLER_INFO describes the caller. Return true iff the
+ type information changed in any way. */
+
+static bool
+ipcp_propagate_types (struct ipa_node_params *caller_info,
+ struct ipa_node_params *callee_info,
+ struct ipa_jump_func *jf, int i)
+{
+ tree cst, binfo;
+
+ switch (jf->type)
+ {
+ case IPA_JF_UNKNOWN:
+ case IPA_JF_CONST_MEMBER_PTR:
+ break;
+
+ case IPA_JF_KNOWN_TYPE:
+ return ipcp_add_param_type (callee_info, i, jf->value.base_binfo);
+
+ case IPA_JF_CONST:
+ cst = jf->value.constant;
+ if (TREE_CODE (cst) != ADDR_EXPR)
+ break;
+ binfo = gimple_get_relevant_ref_binfo (TREE_OPERAND (cst, 0), NULL_TREE);
+ if (!binfo)
+ break;
+ return ipcp_add_param_type (callee_info, i, binfo);
+
+ case IPA_JF_PASS_THROUGH:
+ case IPA_JF_ANCESTOR:
+ return ipcp_copy_types (caller_info, callee_info, i, jf);
+ }
+
+ /* If we reach this we cannot use this parameter for devirtualization. */
+ return !ipa_set_param_cannot_devirtualize (callee_info, i);
+}
+
/* Interprocedural analysis. The algorithm propagates constants from the
caller's parameters to the callee's arguments. */
static void
struct ipa_func_list *wl;
int count;
+ ipa_check_create_node_params ();
+ ipa_check_create_edge_args ();
+
/* Initialize worklist to contain all functions. */
wl = ipa_init_func_list ();
while (wl)
struct ipa_node_params *callee_info = IPA_NODE_REF (cs->callee);
struct ipa_edge_args *args = IPA_EDGE_REF (cs);
- if (ipa_is_called_with_var_arguments (callee_info))
+ if (ipa_is_called_with_var_arguments (callee_info)
+ || !cs->callee->analyzed
+ || ipa_is_called_with_var_arguments (callee_info))
continue;
count = ipa_get_cs_argument_count (args);
{
jump_func = ipa_get_ith_jump_func (args, i);
ipcp_lattice_from_jfunc (info, &inc_lat, jump_func);
- dest_lat = ipcp_get_ith_lattice (callee_info, i);
+ dest_lat = ipcp_get_lattice (callee_info, i);
ipa_lattice_meet (&new_lat, &inc_lat, dest_lat);
if (ipcp_lattice_changed (&new_lat, dest_lat))
{
dest_lat->constant = new_lat.constant;
ipa_push_func_to_list (&wl, cs->callee);
}
+
+ if (ipcp_propagate_types (info, callee_info, jump_func, i))
+ ipa_push_func_to_list (&wl, cs->callee);
}
}
}
static void
ipcp_iterate_stage (void)
{
+ struct cgraph_node *node;
+ n_cloning_candidates = 0;
+
+ if (dump_file)
+ fprintf (dump_file, "\nIPA iterate stage:\n\n");
+
+ if (in_lto_p)
+ ipa_update_after_lto_read ();
+
+ for (node = cgraph_nodes; node; node = node->next)
+ {
+ ipcp_initialize_node_lattices (node);
+ ipcp_compute_node_scale (node);
+ }
+ if (dump_file && (dump_flags & TDF_DETAILS))
+ {
+ ipcp_print_all_lattices (dump_file);
+ ipcp_function_scale_print (dump_file);
+ }
+
ipcp_propagate_stage ();
if (ipcp_change_tops_to_bottom ())
/* Some lattices have changed from IPA_TOP to IPA_BOTTOM.
This change should be propagated. */
- ipcp_propagate_stage ();
+ {
+ gcc_assert (n_cloning_candidates);
+ ipcp_propagate_stage ();
+ }
+ if (dump_file)
+ {
+ fprintf (dump_file, "\nIPA lattices after propagation:\n");
+ ipcp_print_all_lattices (dump_file);
+ if (dump_flags & TDF_DETAILS)
+ ipcp_print_profile_data (dump_file);
+ }
}
/* Check conditions to forbid constant insertion to function described by
NODE. */
static inline bool
-ipcp_node_not_modifiable_p (struct cgraph_node *node)
+ipcp_node_modifiable_p (struct cgraph_node *node)
{
- /* ??? Handle pending sizes case. */
- if (DECL_UNINLINABLE (node->decl))
- return true;
- return false;
-}
-
-/* Print ipa_jump_func data structures to F. */
-static void
-ipcp_print_all_jump_functions (FILE * f)
-{
- struct cgraph_node *node;
- int i, count;
- struct cgraph_edge *cs;
- struct ipa_jump_func *jump_func;
- enum jump_func_type type;
- tree info_type;
-
- fprintf (f, "\nCALLSITE PARAM PRINT\n");
- for (node = cgraph_nodes; node; node = node->next)
- {
- for (cs = node->callees; cs; cs = cs->next_callee)
- {
- fprintf (f, "callsite %s ", cgraph_node_name (node));
- fprintf (f, "-> %s :: \n", cgraph_node_name (cs->callee));
-
- if (ipa_is_called_with_var_arguments (IPA_NODE_REF (cs->callee)))
- continue;
-
- count = ipa_get_cs_argument_count (IPA_EDGE_REF (cs));
- for (i = 0; i < count; i++)
- {
- jump_func = ipa_get_ith_jump_func (IPA_EDGE_REF (cs), i);
- type = jump_func->type;
-
- fprintf (f, " param %d: ", i);
- if (type == IPA_UNKNOWN)
- fprintf (f, "UNKNOWN\n");
- else if (type == IPA_CONST || type == IPA_CONST_REF)
- {
- info_type = jump_func->value.constant;
- fprintf (f, "CONST : ");
- print_generic_expr (f, info_type, 0);
- fprintf (f, "\n");
- }
- else if (type == IPA_PASS_THROUGH)
- {
- fprintf (f, "PASS THROUGH : ");
- fprintf (f, "%d\n", jump_func->value.formal_id);
- }
- }
- }
- }
+ /* Once we will be able to do in-place replacement, we can be more
+ lax here. */
+ return ipcp_versionable_function_p (node);
}
/* Print count scale data structures. */
for (node = cgraph_nodes; node; node = node->next)
{
+ if (!node->analyzed)
+ continue;
fprintf (f, "printing scale for %s: ", cgraph_node_name (node));
fprintf (f, "value is " HOST_WIDE_INT_PRINT_DEC
" \n", (HOST_WIDE_INT) ipcp_get_node_scale (node));
}
}
-/* Print all counts and probabilities of cfg edges of all functions. */
-static void
-ipcp_print_edge_profiles (FILE * f)
-{
- struct cgraph_node *node;
- basic_block bb;
- edge_iterator ei;
- edge e;
-
- for (node = cgraph_nodes; node; node = node->next)
- {
- fprintf (f, "function %s: \n", cgraph_node_name (node));
- if (DECL_SAVED_TREE (node->decl))
- {
- bb =
- ENTRY_BLOCK_PTR_FOR_FUNCTION (DECL_STRUCT_FUNCTION (node->decl));
- fprintf (f, "ENTRY: ");
- fprintf (f, " " HOST_WIDE_INT_PRINT_DEC
- " %d\n", (HOST_WIDE_INT) bb->count, bb->frequency);
-
- if (bb->succs)
- FOR_EACH_EDGE (e, ei, bb->succs)
- {
- if (e->dest ==
- EXIT_BLOCK_PTR_FOR_FUNCTION (DECL_STRUCT_FUNCTION
- (node->decl)))
- fprintf (f, "edge ENTRY -> EXIT, Count");
- else
- fprintf (f, "edge ENTRY -> %d, Count", e->dest->index);
- fprintf (f, " " HOST_WIDE_INT_PRINT_DEC
- " Prob %d\n", (HOST_WIDE_INT) e->count,
- e->probability);
- }
- FOR_EACH_BB_FN (bb, DECL_STRUCT_FUNCTION (node->decl))
- {
- fprintf (f, "bb[%d]: ", bb->index);
- fprintf (f, " " HOST_WIDE_INT_PRINT_DEC
- " %d\n", (HOST_WIDE_INT) bb->count, bb->frequency);
- FOR_EACH_EDGE (e, ei, bb->succs)
- {
- if (e->dest ==
- EXIT_BLOCK_PTR_FOR_FUNCTION (DECL_STRUCT_FUNCTION
- (node->decl)))
- fprintf (f, "edge %d -> EXIT, Count", e->src->index);
- else
- fprintf (f, "edge %d -> %d, Count", e->src->index,
- e->dest->index);
- fprintf (f, " " HOST_WIDE_INT_PRINT_DEC " Prob %d\n",
- (HOST_WIDE_INT) e->count, e->probability);
- }
- }
- }
- }
-}
-
-/* Print counts and frequencies for all basic blocks of all functions. */
-static void
-ipcp_print_bb_profiles (FILE * f)
-{
- basic_block bb;
- struct cgraph_node *node;
-
- for (node = cgraph_nodes; node; node = node->next)
- {
- fprintf (f, "function %s: \n", cgraph_node_name (node));
- if (node->analyzed)
- {
- bb =
- ENTRY_BLOCK_PTR_FOR_FUNCTION (DECL_STRUCT_FUNCTION (node->decl));
- fprintf (f, "ENTRY: Count");
- fprintf (f, " " HOST_WIDE_INT_PRINT_DEC
- " Frequency %d\n", (HOST_WIDE_INT) bb->count,
- bb->frequency);
-
- FOR_EACH_BB_FN (bb, DECL_STRUCT_FUNCTION (node->decl))
- {
- fprintf (f, "bb[%d]: Count", bb->index);
- fprintf (f, " " HOST_WIDE_INT_PRINT_DEC
- " Frequency %d\n", (HOST_WIDE_INT) bb->count,
- bb->frequency);
- }
- bb =
- EXIT_BLOCK_PTR_FOR_FUNCTION (DECL_STRUCT_FUNCTION (node->decl));
- fprintf (f, "EXIT: Count");
- fprintf (f, " " HOST_WIDE_INT_PRINT_DEC
- " Frequency %d\n", (HOST_WIDE_INT) bb->count,
- bb->frequency);
-
- }
- }
-}
-
-/* Print all IPCP data structures to F. */
-static void
-ipcp_print_all_structures (FILE * f)
-{
- ipcp_print_all_lattices (f);
- ipcp_function_scale_print (f);
- ipa_print_all_tree_maps (f);
- ipa_print_all_params_modified (f);
- ipcp_print_all_jump_functions (f);
-}
-
/* Print profile info for all functions. */
static void
ipcp_print_profile_data (FILE * f)
ipcp_print_func_profile_counts (f);
fprintf (f, "\nCS COUNTS stage:\n");
ipcp_print_call_profile_counts (f);
- fprintf (f, "\nBB COUNTS and FREQUENCIES :\n");
- ipcp_print_bb_profiles (f);
- fprintf (f, "\nCFG EDGES COUNTS and PROBABILITIES :\n");
- ipcp_print_edge_profiles (f);
}
/* Build and initialize ipa_replace_map struct according to LAT. This struct is
PARM_TREE is the formal parameter found to be constant. LAT represents the
constant. */
static struct ipa_replace_map *
-ipcp_create_replace_map (struct function *func, tree parm_tree,
- struct ipcp_lattice *lat)
+ipcp_create_replace_map (tree parm_tree, struct ipcp_lattice *lat)
{
struct ipa_replace_map *replace_map;
tree const_val;
- replace_map = XCNEW (struct ipa_replace_map);
- gcc_assert (ipcp_lat_is_const (lat));
- if (lat->type != IPA_CONST_VALUE_REF
- && is_gimple_reg (parm_tree) && gimple_default_def (func, parm_tree)
- && !SSA_NAME_OCCURS_IN_ABNORMAL_PHI (gimple_default_def (func,
- parm_tree)))
- {
- if (dump_file)
- fprintf (dump_file, "replacing param with const\n");
- const_val = build_const_val (lat, TREE_TYPE (parm_tree));
- replace_map->old_tree =gimple_default_def (func, parm_tree);
- replace_map->new_tree = const_val;
- replace_map->replace_p = true;
- replace_map->ref_p = false;
- }
- else
+ replace_map = ggc_alloc_ipa_replace_map ();
+ const_val = build_const_val (lat, TREE_TYPE (parm_tree));
+ if (dump_file)
{
- replace_map->old_tree = NULL;
- replace_map->new_tree = NULL;
- replace_map->replace_p = false;
- replace_map->ref_p = false;
+ fprintf (dump_file, " replacing param ");
+ print_generic_expr (dump_file, parm_tree, 0);
+ fprintf (dump_file, " with const ");
+ print_generic_expr (dump_file, const_val, 0);
+ fprintf (dump_file, "\n");
}
+ replace_map->old_tree = parm_tree;
+ replace_map->new_tree = const_val;
+ replace_map->replace_p = true;
+ replace_map->ref_p = false;
return replace_map;
}
{
struct ipa_node_params *orig_callee_info;
int i, count;
- struct ipa_jump_func *jump_func;
+ struct cgraph_node *node = cs->callee, *orig;
+
+ if (!n_cloning_candidates)
+ return false;
+
+ if ((orig = ipcp_get_orig_node (node)) != NULL)
+ node = orig;
+ if (ipcp_get_orig_node (cs->caller))
+ return false;
- orig_callee_info = IPA_NODE_REF (ipcp_get_orig_node (cs->callee));
+ orig_callee_info = IPA_NODE_REF (node);
count = ipa_get_param_count (orig_callee_info);
for (i = 0; i < count; i++)
{
- struct ipcp_lattice *lat = ipcp_get_ith_lattice (orig_callee_info, i);
- if (ipcp_lat_is_const (lat))
- {
- jump_func = ipa_get_ith_jump_func (IPA_EDGE_REF (cs), i);
- if (!ipcp_lat_is_const (lat))
- return true;
- }
+ struct ipcp_lattice *lat = ipcp_get_lattice (orig_callee_info, i);
+ struct ipa_jump_func *jump_func;
+
+ jump_func = ipa_get_ith_jump_func (IPA_EDGE_REF (cs), i);
+ if ((ipcp_lat_is_const (lat)
+ && jump_func->type != IPA_JF_CONST)
+ || (!ipa_param_cannot_devirtualize_p (orig_callee_info, i)
+ && !ipa_param_types_vec_empty (orig_callee_info, i)
+ && jump_func->type != IPA_JF_CONST
+ && jump_func->type != IPA_JF_KNOWN_TYPE))
+ return true;
}
return false;
static void
ipcp_update_callgraph (void)
{
- struct cgraph_node *node, *orig_callee;
- struct cgraph_edge *cs;
+ struct cgraph_node *node;
for (node = cgraph_nodes; node; node = node->next)
- {
- /* want to fix only original nodes */
- if (ipcp_node_is_clone (node))
- continue;
- for (cs = node->callees; cs; cs = cs->next_callee)
- if (ipcp_node_is_clone (cs->callee))
+ if (node->analyzed && ipcp_node_is_clone (node))
+ {
+ bitmap args_to_skip = BITMAP_ALLOC (NULL);
+ struct cgraph_node *orig_node = ipcp_get_orig_node (node);
+ struct ipa_node_params *info = IPA_NODE_REF (orig_node);
+ int i, count = ipa_get_param_count (info);
+ struct cgraph_edge *cs, *next;
+
+ for (i = 0; i < count; i++)
{
- /* Callee is a cloned node */
- orig_callee = ipcp_get_orig_node (cs->callee);
- if (ipcp_need_redirect_p (cs))
+ struct ipcp_lattice *lat = ipcp_get_lattice (info, i);
+
+ /* We can proactively remove obviously unused arguments. */
+ if (!ipa_is_param_used (info, i))
{
- cgraph_redirect_edge_callee (cs, orig_callee);
- TREE_OPERAND (CALL_EXPR_FN (get_call_expr_in (cs->call_stmt)),
- 0) =
- orig_callee->decl;
+ bitmap_set_bit (args_to_skip, i);
+ continue;
}
- }
- }
-}
-/* Update all cfg basic blocks in NODE according to SCALE. */
-static void
-ipcp_update_bb_counts (struct cgraph_node *node, gcov_type scale)
-{
- basic_block bb;
-
- FOR_ALL_BB_FN (bb, DECL_STRUCT_FUNCTION (node->decl))
- bb->count = bb->count * scale / REG_BR_PROB_BASE;
-}
-
-/* Update all cfg edges in NODE according to SCALE. */
-static void
-ipcp_update_edges_counts (struct cgraph_node *node, gcov_type scale)
-{
- basic_block bb;
- edge_iterator ei;
- edge e;
-
- FOR_ALL_BB_FN (bb, DECL_STRUCT_FUNCTION (node->decl))
- FOR_EACH_EDGE (e, ei, bb->succs)
- e->count = e->count * scale / REG_BR_PROB_BASE;
+ if (lat->type == IPA_CONST_VALUE)
+ bitmap_set_bit (args_to_skip, i);
+ }
+ for (cs = node->callers; cs; cs = next)
+ {
+ next = cs->next_caller;
+ if (!ipcp_node_is_clone (cs->caller) && ipcp_need_redirect_p (cs))
+ {
+ if (dump_file)
+ fprintf (dump_file, "Redirecting edge %s/%i -> %s/%i "
+ "back to %s/%i.",
+ cgraph_node_name (cs->caller), cs->caller->uid,
+ cgraph_node_name (cs->callee), cs->callee->uid,
+ cgraph_node_name (orig_node), orig_node->uid);
+ cgraph_redirect_edge_callee (cs, orig_node);
+ }
+ }
+ }
}
/* Update profiling info for versioned functions and the functions they were
cs->count = cs->count * scale / REG_BR_PROB_BASE;
for (cs = orig_node->callees; cs; cs = cs->next_callee)
cs->count = cs->count * scale_complement / REG_BR_PROB_BASE;
- ipcp_update_bb_counts (node, scale);
- ipcp_update_bb_counts (orig_node, scale_complement);
- ipcp_update_edges_counts (node, scale);
- ipcp_update_edges_counts (orig_node, scale_complement);
}
}
}
+/* If NODE was cloned, how much would program grow? */
+static long
+ipcp_estimate_growth (struct cgraph_node *node)
+{
+ struct cgraph_edge *cs;
+ int redirectable_node_callers = 0;
+ int removable_args = 0;
+ bool need_original
+ = !cgraph_will_be_removed_from_program_if_no_direct_calls (node);
+ struct ipa_node_params *info;
+ int i, count;
+ int growth;
+
+ for (cs = node->callers; cs != NULL; cs = cs->next_caller)
+ if (cs->caller == node || !ipcp_need_redirect_p (cs))
+ redirectable_node_callers++;
+ else
+ need_original = true;
+
+ /* If we will be able to fully replace orignal node, we never increase
+ program size. */
+ if (!need_original)
+ return 0;
+
+ info = IPA_NODE_REF (node);
+ count = ipa_get_param_count (info);
+ for (i = 0; i < count; i++)
+ {
+ struct ipcp_lattice *lat = ipcp_get_lattice (info, i);
+
+ /* We can proactively remove obviously unused arguments. */
+ if (!ipa_is_param_used (info, i))
+ removable_args++;
+
+ if (lat->type == IPA_CONST_VALUE)
+ removable_args++;
+ }
+
+ /* We make just very simple estimate of savings for removal of operand from
+ call site. Precise cost is dificult to get, as our size metric counts
+ constants and moves as free. Generally we are looking for cases that
+ small function is called very many times. */
+ growth = node->local.inline_summary.self_size
+ - removable_args * redirectable_node_callers;
+ if (growth < 0)
+ return 0;
+ return growth;
+}
+
+
+/* Estimate cost of cloning NODE. */
+static long
+ipcp_estimate_cloning_cost (struct cgraph_node *node)
+{
+ int freq_sum = 1;
+ gcov_type count_sum = 1;
+ struct cgraph_edge *e;
+ int cost;
+
+ cost = ipcp_estimate_growth (node) * 1000;
+ if (!cost)
+ {
+ if (dump_file)
+ fprintf (dump_file, "Versioning of %s will save code size\n",
+ cgraph_node_name (node));
+ return 0;
+ }
+
+ for (e = node->callers; e; e = e->next_caller)
+ if (!bitmap_bit_p (dead_nodes, e->caller->uid)
+ && !ipcp_need_redirect_p (e))
+ {
+ count_sum += e->count;
+ freq_sum += e->frequency + 1;
+ }
+
+ if (max_count)
+ cost /= count_sum * 1000 / max_count + 1;
+ else
+ cost /= freq_sum * 1000 / REG_BR_PROB_BASE + 1;
+ if (dump_file)
+ fprintf (dump_file, "Cost of versioning %s is %i, (size: %i, freq: %i)\n",
+ cgraph_node_name (node), cost, node->local.inline_summary.self_size,
+ freq_sum);
+ return cost + 1;
+}
+
+/* Walk indirect calls of NODE and if any polymorphic can be turned into a
+ direct one now, do so. */
+
+static void
+ipcp_process_devirtualization_opportunities (struct cgraph_node *node)
+{
+ struct ipa_node_params *info = IPA_NODE_REF (node);
+ struct cgraph_edge *ie, *next_ie;
+
+ for (ie = node->indirect_calls; ie; ie = next_ie)
+ {
+ int param_index, types_count, j;
+ HOST_WIDE_INT token;
+ tree target;
+
+ next_ie = ie->next_callee;
+ if (!ie->indirect_info->polymorphic)
+ continue;
+ param_index = ie->indirect_info->param_index;
+ if (param_index == -1
+ || ipa_param_cannot_devirtualize_p (info, param_index)
+ || ipa_param_types_vec_empty (info, param_index))
+ continue;
+
+ token = ie->indirect_info->otr_token;
+ target = NULL_TREE;
+ types_count = VEC_length (tree, info->params[param_index].types);
+ for (j = 0; j < types_count; j++)
+ {
+ tree binfo = VEC_index (tree, info->params[param_index].types, j);
+ tree t = gimple_fold_obj_type_ref_known_binfo (token, binfo);
+
+ if (!t)
+ {
+ target = NULL_TREE;
+ break;
+ }
+ else if (!target)
+ target = t;
+ else if (target != t)
+ {
+ target = NULL_TREE;
+ break;
+ }
+ }
+
+ if (target)
+ ipa_make_edge_direct_to_target (ie, target);
+ }
+}
+
+/* Return number of live constant parameters. */
+static int
+ipcp_const_param_count (struct cgraph_node *node)
+{
+ int const_param = 0;
+ struct ipa_node_params *info = IPA_NODE_REF (node);
+ int count = ipa_get_param_count (info);
+ int i;
+
+ for (i = 0; i < count; i++)
+ {
+ struct ipcp_lattice *lat = ipcp_get_lattice (info, i);
+ if ((ipcp_lat_is_insertable (lat)
+ /* Do not count obviously unused arguments. */
+ && ipa_is_param_used (info, i))
+ || (!ipa_param_cannot_devirtualize_p (info, i)
+ && !ipa_param_types_vec_empty (info, i)))
+ const_param++;
+ }
+ return const_param;
+}
+
+/* Given that a formal parameter of NODE given by INDEX is known to be constant
+ CST, try to find any indirect edges that can be made direct and make them
+ so. Note that INDEX is the number the parameter at the time of analyzing
+ parameter uses and parameter removals should not be considered for it. (In
+ fact, the parameter itself has just been removed.) */
+
+static void
+ipcp_discover_new_direct_edges (struct cgraph_node *node, int index, tree cst)
+{
+ struct cgraph_edge *ie, *next_ie;
+
+ for (ie = node->indirect_calls; ie; ie = next_ie)
+ {
+ struct cgraph_indirect_call_info *ici = ie->indirect_info;
+
+ next_ie = ie->next_callee;
+ if (ici->param_index != index)
+ continue;
+
+ if (ici->polymorphic)
+ {
+ tree binfo;
+ HOST_WIDE_INT token;
+
+ if (TREE_CODE (cst) != ADDR_EXPR)
+ continue;
+
+ binfo = gimple_get_relevant_ref_binfo (TREE_OPERAND (cst, 0),
+ NULL_TREE);
+ if (!binfo)
+ continue;
+ gcc_assert (ie->indirect_info->anc_offset == 0);
+ token = ie->indirect_info->otr_token;
+ cst = gimple_fold_obj_type_ref_known_binfo (token, binfo);
+ if (!cst)
+ continue;
+ }
+
+ ipa_make_edge_direct_to_target (ie, cst);
+ }
+}
+
+
/* Propagate the constant parameters found by ipcp_iterate_stage()
to the function's code. */
static void
ipcp_insert_stage (void)
{
struct cgraph_node *node, *node1 = NULL;
- int i, const_param;
+ int i;
VEC (cgraph_edge_p, heap) * redirect_callers;
- varray_type replace_trees;
- struct cgraph_edge *cs;
+ VEC (ipa_replace_map_p,gc)* replace_trees;
int node_callers, count;
tree parm_tree;
struct ipa_replace_map *replace_param;
+ fibheap_t heap;
+ long overall_size = 0, new_size = 0;
+ long max_new_size;
+
+ ipa_check_create_node_params ();
+ ipa_check_create_edge_args ();
+ if (dump_file)
+ fprintf (dump_file, "\nIPA insert stage:\n\n");
+ dead_nodes = BITMAP_ALLOC (NULL);
+
+ for (node = cgraph_nodes; node; node = node->next)
+ if (node->analyzed)
+ {
+ if (node->count > max_count)
+ max_count = node->count;
+ overall_size += node->local.inline_summary.self_size;
+ }
+
+ max_new_size = overall_size;
+ if (max_new_size < PARAM_VALUE (PARAM_LARGE_UNIT_INSNS))
+ max_new_size = PARAM_VALUE (PARAM_LARGE_UNIT_INSNS);
+ max_new_size = max_new_size * PARAM_VALUE (PARAM_IPCP_UNIT_GROWTH) / 100 + 1;
+
+ /* First collect all functions we proved to have constant arguments to
+ heap. */
+ heap = fibheap_new ();
for (node = cgraph_nodes; node; node = node->next)
{
- struct ipa_node_params *info = IPA_NODE_REF (node);
- /* Propagation of the constant is forbidden in
- certain conditions. */
- if (!node->analyzed || ipcp_node_not_modifiable_p (node)
- || ipa_is_called_with_var_arguments (info))
+ struct ipa_node_params *info;
+ /* Propagation of the constant is forbidden in certain conditions. */
+ if (!node->analyzed || !ipcp_node_modifiable_p (node))
+ continue;
+ info = IPA_NODE_REF (node);
+ if (ipa_is_called_with_var_arguments (info))
continue;
- const_param = 0;
- count = ipa_get_param_count (info);
- for (i = 0; i < count; i++)
+ if (ipcp_const_param_count (node))
+ node->aux = fibheap_insert (heap, ipcp_estimate_cloning_cost (node),
+ node);
+ }
+
+ /* Now clone in priority order until code size growth limits are met or
+ heap is emptied. */
+ while (!fibheap_empty (heap))
+ {
+ struct ipa_node_params *info;
+ int growth = 0;
+ bitmap args_to_skip;
+ struct cgraph_edge *cs;
+
+ node = (struct cgraph_node *)fibheap_extract_min (heap);
+ node->aux = NULL;
+ if (dump_file)
+ fprintf (dump_file, "considering function %s\n",
+ cgraph_node_name (node));
+
+ growth = ipcp_estimate_growth (node);
+
+ if (new_size + growth > max_new_size)
+ break;
+ if (growth
+ && optimize_function_for_size_p (DECL_STRUCT_FUNCTION (node->decl)))
{
- struct ipcp_lattice *lat = ipcp_get_ith_lattice (info, i);
- if (ipcp_lat_is_const (lat))
- const_param++;
+ if (dump_file)
+ fprintf (dump_file, "Not versioning, cold code would grow");
+ continue;
}
- if (const_param == 0)
- continue;
- VARRAY_GENERIC_PTR_INIT (replace_trees, const_param, "replace_trees");
+
+ new_size += growth;
+
+ /* Look if original function becomes dead after clonning. */
+ for (cs = node->callers; cs != NULL; cs = cs->next_caller)
+ if (cs->caller == node || ipcp_need_redirect_p (cs))
+ break;
+ if (!cs && cgraph_will_be_removed_from_program_if_no_direct_calls (node))
+ bitmap_set_bit (dead_nodes, node->uid);
+
+ info = IPA_NODE_REF (node);
+ count = ipa_get_param_count (info);
+
+ replace_trees = VEC_alloc (ipa_replace_map_p, gc, 1);
+ args_to_skip = BITMAP_GGC_ALLOC ();
for (i = 0; i < count; i++)
{
- struct ipcp_lattice *lat = ipcp_get_ith_lattice (info, i);
- if (ipcp_lat_is_const (lat))
+ struct ipcp_lattice *lat = ipcp_get_lattice (info, i);
+ parm_tree = ipa_get_param (info, i);
+
+ /* We can proactively remove obviously unused arguments. */
+ if (!ipa_is_param_used (info, i))
+ {
+ bitmap_set_bit (args_to_skip, i);
+ continue;
+ }
+
+ if (lat->type == IPA_CONST_VALUE)
{
- parm_tree = ipa_get_ith_param (info, i);
replace_param =
- ipcp_create_replace_map (DECL_STRUCT_FUNCTION (node->decl),
- parm_tree, lat);
- VARRAY_PUSH_GENERIC_PTR (replace_trees, replace_param);
+ ipcp_create_replace_map (parm_tree, lat);
+ VEC_safe_push (ipa_replace_map_p, gc, replace_trees, replace_param);
+ bitmap_set_bit (args_to_skip, i);
}
}
+
/* Compute how many callers node has. */
node_callers = 0;
for (cs = node->callers; cs != NULL; cs = cs->next_caller)
node_callers++;
redirect_callers = VEC_alloc (cgraph_edge_p, heap, node_callers);
for (cs = node->callers; cs != NULL; cs = cs->next_caller)
- VEC_quick_push (cgraph_edge_p, redirect_callers, cs);
+ if (!cs->indirect_inlining_edge)
+ VEC_quick_push (cgraph_edge_p, redirect_callers, cs);
+
/* Redirecting all the callers of the node to the
new versioned node. */
node1 =
- cgraph_function_versioning (node, redirect_callers, replace_trees);
+ cgraph_create_virtual_clone (node, redirect_callers, replace_trees,
+ args_to_skip, "constprop");
+ args_to_skip = NULL;
VEC_free (cgraph_edge_p, heap, redirect_callers);
- VARRAY_CLEAR (replace_trees);
+ replace_trees = NULL;
+
if (node1 == NULL)
continue;
+ ipcp_process_devirtualization_opportunities (node1);
+
if (dump_file)
- fprintf (dump_file, "versioned function %s\n",
- cgraph_node_name (node));
+ fprintf (dump_file, "versioned function %s with growth %i, overall %i\n",
+ cgraph_node_name (node), (int)growth, (int)new_size);
ipcp_init_cloned_node (node, node1);
- if (const_param > 0)
+
+ info = IPA_NODE_REF (node);
+ for (i = 0; i < count; i++)
{
- push_cfun (DECL_STRUCT_FUNCTION (node1->decl));
- tree_register_cfg_hooks ();
- current_function_decl = node1->decl;
+ struct ipcp_lattice *lat = ipcp_get_lattice (info, i);
+ if (lat->type == IPA_CONST_VALUE)
+ ipcp_discover_new_direct_edges (node1, i, lat->constant);
+ }
- for (i = 0; i < count; i++)
- {
- struct ipcp_lattice *lat = ipcp_get_ith_lattice (info, i);
- if (ipcp_lat_is_const (lat))
- {
- parm_tree = ipa_get_ith_param (info, i);
- if (lat->type != IPA_CONST_VALUE_REF
- && !is_gimple_reg (parm_tree))
- ipcp_propagate_one_const (node1, i, lat);
- }
- }
- if (gimple_in_ssa_p (cfun))
- {
- update_ssa (TODO_update_ssa);
-#ifdef ENABLE_CHECKING
- verify_ssa (true);
-#endif
- }
- free_dominance_info (CDI_DOMINATORS);
- free_dominance_info (CDI_POST_DOMINATORS);
- pop_cfun ();
- current_function_decl = NULL;
- }
if (dump_file)
dump_function_to_file (node1->decl, dump_file, dump_flags);
+
+ for (cs = node->callees; cs; cs = cs->next_callee)
+ if (cs->callee->aux)
+ {
+ fibheap_delete_node (heap, (fibnode_t) cs->callee->aux);
+ cs->callee->aux = fibheap_insert (heap,
+ ipcp_estimate_cloning_cost (cs->callee),
+ cs->callee);
+ }
+ }
+
+ while (!fibheap_empty (heap))
+ {
+ if (dump_file)
+ fprintf (dump_file, "skipping function %s\n",
+ cgraph_node_name (node));
+ node = (struct cgraph_node *) fibheap_extract_min (heap);
+ node->aux = NULL;
}
+ fibheap_delete (heap);
+ BITMAP_FREE (dead_nodes);
ipcp_update_callgraph ();
ipcp_update_profiling ();
}
static unsigned int
ipcp_driver (void)
{
- if (dump_file)
- fprintf (dump_file, "\nIPA constant propagation start:\n");
- ipa_create_all_node_params ();
- ipa_create_all_edge_args ();
- /* 1. Call the init stage to initialize
- the ipa_node_params and ipa_edge_args structures. */
- ipcp_init_stage ();
+ cgraph_remove_unreachable_nodes (true,dump_file);
if (dump_file)
{
fprintf (dump_file, "\nIPA structures before propagation:\n");
- ipcp_print_all_structures (dump_file);
+ if (dump_flags & TDF_DETAILS)
+ ipa_print_all_params (dump_file);
+ ipa_print_all_jump_functions (dump_file);
}
/* 2. Do the interprocedural propagation. */
ipcp_iterate_stage ();
- if (dump_file)
- {
- fprintf (dump_file, "\nIPA structures after propagation:\n");
- ipcp_print_all_structures (dump_file);
- fprintf (dump_file, "\nProfiling info before insert stage:\n");
- ipcp_print_profile_data (dump_file);
- }
/* 3. Insert the constants found to the functions. */
ipcp_insert_stage ();
- if (dump_file)
+ if (dump_file && (dump_flags & TDF_DETAILS))
{
fprintf (dump_file, "\nProfiling info after insert stage:\n");
ipcp_print_profile_data (dump_file);
}
/* Free all IPCP structures. */
- ipa_free_all_node_params ();
- ipa_free_all_edge_args ();
+ ipa_free_all_structures_after_ipa_cp ();
if (dump_file)
fprintf (dump_file, "\nIPA constant propagation end\n");
- cgraph_remove_unreachable_nodes (true, NULL);
return 0;
}
+/* Initialization and computation of IPCP data structures. This is the initial
+ intraprocedural analysis of functions, which gathers information to be
+ propagated later on. */
+
+static void
+ipcp_generate_summary (void)
+{
+ struct cgraph_node *node;
+
+ if (dump_file)
+ fprintf (dump_file, "\nIPA constant propagation start:\n");
+ ipa_check_create_node_params ();
+ ipa_check_create_edge_args ();
+ ipa_register_cgraph_hooks ();
+
+ for (node = cgraph_nodes; node; node = node->next)
+ if (node->analyzed)
+ {
+ /* Unreachable nodes should have been eliminated before ipcp. */
+ gcc_assert (node->needed || node->reachable);
+
+ node->local.versionable = tree_versionable_function_p (node->decl);
+ ipa_analyze_node (node);
+ }
+}
+
+/* Write ipcp summary for nodes in SET. */
+static void
+ipcp_write_summary (cgraph_node_set set,
+ varpool_node_set vset ATTRIBUTE_UNUSED)
+{
+ ipa_prop_write_jump_functions (set);
+}
+
+/* Read ipcp summary. */
+static void
+ipcp_read_summary (void)
+{
+ ipa_prop_read_jump_functions ();
+}
+
/* Gate for IPCP optimization. */
static bool
cgraph_gate_cp (void)
{
- return flag_ipa_cp;
+ /* FIXME: We should remove the optimize check after we ensure we never run
+ IPA passes when not optimizng. */
+ return flag_ipa_cp && optimize;
}
-struct simple_ipa_opt_pass pass_ipa_cp =
+struct ipa_opt_pass_d pass_ipa_cp =
{
{
- SIMPLE_IPA_PASS,
+ IPA_PASS,
"cp", /* name */
cgraph_gate_cp, /* gate */
ipcp_driver, /* execute */
0, /* static_pass_number */
TV_IPA_CONSTANT_PROP, /* tv_id */
0, /* properties_required */
- PROP_trees, /* properties_provided */
+ 0, /* properties_provided */
0, /* properties_destroyed */
0, /* todo_flags_start */
- TODO_dump_cgraph | TODO_dump_func /* todo_flags_finish */
- }
+ TODO_dump_cgraph | TODO_dump_func |
+ TODO_remove_functions | TODO_ggc_collect /* todo_flags_finish */
+ },
+ ipcp_generate_summary, /* generate_summary */
+ ipcp_write_summary, /* write_summary */
+ ipcp_read_summary, /* read_summary */
+ NULL, /* write_optimization_summary */
+ NULL, /* read_optimization_summary */
+ NULL, /* stmt_fixup */
+ 0, /* TODOs */
+ NULL, /* function_transform */
+ NULL, /* variable_transform */
};
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