/* 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).
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"
ipcp_init_cloned_node (struct cgraph_node *orig_node,
struct cgraph_node *new_node)
{
- ipa_check_create_node_params ();
- ipa_initialize_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;
}
-/* Perform intraprocedrual analysis needed for ipcp. */
-static void
-ipcp_analyze_node (struct cgraph_node *node)
-{
- /* Unreachable nodes should have been eliminated before ipcp. */
- gcc_assert (node->needed || node->reachable);
-
- ipa_initialize_node_params (node);
- ipa_detect_param_modifications (node);
-}
-
-/* Recompute all local information since node might've got new
- direct calls after cloning. */
-static void
-ipcp_update_cloned_node (struct cgraph_node *new_node)
-{
- /* We might've introduced new direct calls. */
- push_cfun (DECL_STRUCT_FUNCTION (new_node->decl));
- current_function_decl = new_node->decl;
- rebuild_cgraph_edges ();
-
- /* Indirect inlinng rely on fact that we've already analyzed
- the body.. */
- if (flag_indirect_inlining)
- {
- struct cgraph_edge *cs;
-
- ipcp_analyze_node (new_node);
-
- for (cs = new_node->callees; cs; cs = cs->next_callee)
- {
- ipa_count_arguments (cs);
- ipa_compute_jump_functions (cs);
- }
- }
- pop_cfun ();
- current_function_decl = NULL;
-}
-
/* Return scale for NODE. */
static inline gcov_type
ipcp_get_node_scale (struct cgraph_node *node)
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:
ipcp_lattice_from_jfunc (struct ipa_node_params *info, struct ipcp_lattice *lat,
struct ipa_jump_func *jfunc)
{
- 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_PASS_THROUGH)
+ else if (jfunc->type == IPA_JF_PASS_THROUGH)
{
struct ipcp_lattice *caller_lat;
+ tree cst;
- caller_lat = ipcp_get_lattice (info, jfunc->value.formal_id);
+ caller_lat = ipcp_get_lattice (info, jfunc->value.pass_through.formal_id);
lat->type = caller_lat->type;
- lat->constant = caller_lat->constant;
+ 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_JF_ANCESTOR)
+ {
+ struct ipcp_lattice *caller_lat;
+ tree t;
+
+ caller_lat = ipcp_get_lattice (info, jfunc->value.ancestor.formal_id);
+ lat->type = caller_lat->type;
+ 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);
+ t = build_ref_for_offset (EXPR_LOCATION (t), t,
+ jfunc->value.ancestor.offset,
+ jfunc->value.ancestor.type, NULL, false);
+ lat->constant = build_fold_addr_expr (t);
}
else
lat->type = IPA_BOTTOM;
fprintf (f, " param [%d]: ", i);
if (lat->type == IPA_CONST_VALUE)
{
+ 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, "type is TOP\n");
+ 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, "type is BOTTOM\n");
+ fprintf (f, "\n");
}
}
}
+/* Return true if ipcp algorithms would allow cloning NODE. */
+
+static bool
+ipcp_versionable_function_p (struct cgraph_node *node)
+{
+ struct cgraph_edge *edge;
+
+ /* There are a number of generic reasons functions cannot be versioned. We
+ also cannot remove parameters if there are type attributes such as fnspec
+ present. */
+ if (!node->local.versionable
+ || TYPE_ATTRIBUTES (TREE_TYPE (node->decl)))
+ 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 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;
+ }
+
+ return true;
+}
+
/* Return true if this NODE is viable candidate for cloning. */
static bool
ipcp_cloning_candidate_p (struct cgraph_node *node)
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 (!node->needed || !node->analyzed)
+ if (cgraph_only_called_directly_p (node) || !node->analyzed)
return false;
+ /* When function address is taken, we are pretty sure it will be called in hidden way. */
+ if (node->address_taken)
+ {
+ if (dump_file)
+ fprintf (dump_file, "Not considering %s for cloning; address is taken.\n",
+ cgraph_node_name (node));
+ return false;
+ }
+
if (cgraph_function_body_availability (node) <= AVAIL_OVERWRITABLE)
{
if (dump_file)
cgraph_node_name (node));
return false;
}
- if (!tree_versionable_function_p (node->decl))
+ if (!ipcp_versionable_function_p (node))
{
if (dump_file)
fprintf (dump_file, "Not considering %s for cloning; body is not versionable.\n",
if (cgraph_maybe_hot_edge_p (e))
n_hot_calls ++;
}
-
+
if (!n_calls)
{
if (dump_file)
cgraph_node_name (node));
return false;
}
- if (node->local.inline_summary.self_insns < n_calls)
+ 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; no hot calls.\n",
cgraph_node_name (node));
+ return false;
}
if (dump_file)
fprintf (dump_file, "Considering %s for cloning.\n",
return true;
}
+/* 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)
+{
+ 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;
+}
+
/* 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. */
if (ipa_is_called_with_var_arguments (info))
type = IPA_BOTTOM;
- else if (!node->needed)
+ else if (node->local.local)
type = IPA_TOP;
/* When cloning is allowed, we can assume that externally visible functions
are not called. We will compensate this by cloning later. */
type = IPA_BOTTOM;
for (i = 0; i < ipa_get_param_count (info) ; i++)
- ipcp_get_lattice (info, i)->type = type;
+ {
+ ipcp_get_lattice (info, i)->type = type;
+ if (type == IPA_BOTTOM)
+ ipa_set_param_cannot_devirtualize (info, i);
+ }
}
/* build INTEGER_CST tree with type TREE_TYPE and value according to LAT.
/* 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)
- if (node->analyzed)
- ipcp_analyze_node (node);
- for (node = cgraph_nodes; node; node = node->next)
- {
- if (!node->analyzed)
- continue;
- /* building jump functions */
- for (cs = node->callees; cs; cs = cs->next_callee)
- {
- if (!cs->callee->analyzed)
- continue;
- 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));
- if (flag_indirect_inlining)
- ipa_compute_jump_functions (cs);
- }
- 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. */
}
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_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);
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);
}
}
}
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);
{
/* Once we will be able to do in-place replacement, we can be more
lax here. */
- return tree_versionable_function_p (node->decl);
+ return ipcp_versionable_function_p (node);
}
/* Print count scale data structures. */
}
}
-/* 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 (node->analyzed)
- {
- 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 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
struct ipa_replace_map *replace_map;
tree const_val;
- replace_map = XCNEW (struct ipa_replace_map);
+ replace_map = ggc_alloc_ipa_replace_map ();
const_val = build_const_val (lat, TREE_TYPE (parm_tree));
if (dump_file)
{
{
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)
for (i = 0; i < count; i++)
{
struct ipcp_lattice *lat = ipcp_get_lattice (orig_callee_info, i);
- if (ipcp_lat_is_const (lat))
- {
- jump_func = ipa_get_ith_jump_func (IPA_EDGE_REF (cs), i);
- if (jump_func->type != IPA_CONST)
- return true;
- }
+ 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;
for (i = 0; i < count; i++)
{
struct ipcp_lattice *lat = ipcp_get_lattice (info, i);
- tree parm_tree = ipa_get_param (info, i);
/* We can proactively remove obviously unused arguments. */
- if (is_gimple_reg (parm_tree)
- && !gimple_default_def (DECL_STRUCT_FUNCTION (orig_node->decl),
- parm_tree))
+ if (!ipa_is_param_used (info, i))
{
bitmap_set_bit (args_to_skip, i);
continue;
for (cs = node->callers; cs; cs = next)
{
next = cs->next_caller;
- if (ipcp_node_is_clone (cs->caller) || !ipcp_need_redirect_p (cs))
- {
- gimple new_stmt;
- gimple_stmt_iterator gsi;
-
- current_function_decl = cs->caller->decl;
- push_cfun (DECL_STRUCT_FUNCTION (cs->caller->decl));
-
- new_stmt = gimple_copy_call_skip_args (cs->call_stmt,
- args_to_skip);
- gsi = gsi_for_stmt (cs->call_stmt);
- gsi_replace (&gsi, new_stmt, true);
- cgraph_set_call_stmt (cs, new_stmt);
- pop_cfun ();
- current_function_decl = NULL;
- }
- else
+ 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);
- gimple_call_set_fndecl (cs->call_stmt, orig_node->decl);
}
}
}
}
-/* 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;
-}
-
/* Update profiling info for versioned functions and the functions they were
versioned from. */
static void
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);
}
}
}
struct cgraph_edge *cs;
int redirectable_node_callers = 0;
int removable_args = 0;
- bool need_original = node->needed;
+ 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 (!ipcp_need_redirect_p (cs))
+ if (cs->caller == node || !ipcp_need_redirect_p (cs))
redirectable_node_callers++;
else
need_original = true;
for (i = 0; i < count; i++)
{
struct ipcp_lattice *lat = ipcp_get_lattice (info, i);
- tree parm_tree = ipa_get_param (info, i);
/* We can proactively remove obviously unused arguments. */
- if (is_gimple_reg (parm_tree)
- && !gimple_default_def (DECL_STRUCT_FUNCTION (node->decl),
- parm_tree))
+ if (!ipa_is_param_used (info, i))
removable_args++;
if (lat->type == IPA_CONST_VALUE)
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_insns
+ growth = node->local.inline_summary.self_size
- removable_args * redirectable_node_callers;
if (growth < 0)
return 0;
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_insns,
+ 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)
for (i = 0; i < count; i++)
{
struct ipcp_lattice *lat = ipcp_get_lattice (info, i);
- tree parm_tree = ipa_get_param (info, i);
- if (ipcp_lat_is_insertable (lat)
+ if ((ipcp_lat_is_insertable (lat)
/* Do not count obviously unused arguments. */
- && (!is_gimple_reg (parm_tree)
- || gimple_default_def (DECL_STRUCT_FUNCTION (node->decl),
- parm_tree)))
+ && 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
struct cgraph_node *node, *node1 = NULL;
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_insns = 0, new_insns = 0;
- long max_new_insns;
+ long overall_size = 0, new_size = 0;
+ long max_new_size;
ipa_check_create_node_params ();
ipa_check_create_edge_args ();
{
if (node->count > max_count)
max_count = node->count;
- overall_insns += node->local.inline_summary.self_insns;
+ overall_size += node->local.inline_summary.self_size;
}
- max_new_insns = overall_insns;
- if (max_new_insns < PARAM_VALUE (PARAM_LARGE_UNIT_INSNS))
- max_new_insns = PARAM_VALUE (PARAM_LARGE_UNIT_INSNS);
- max_new_insns = max_new_insns * PARAM_VALUE (PARAM_IPCP_UNIT_GROWTH) / 100 + 1;
+ 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. */
+ /* First collect all functions we proved to have constant arguments to
+ heap. */
heap = fibheap_new ();
for (node = cgraph_nodes; node; node = node->next)
{
if (ipa_is_called_with_var_arguments (info))
continue;
if (ipcp_const_param_count (node))
- node->aux = fibheap_insert (heap, ipcp_estimate_cloning_cost (node), 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
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;
growth = ipcp_estimate_growth (node);
- if (new_insns + growth > max_new_insns)
+ if (new_size + growth > max_new_size)
break;
if (growth
&& optimize_function_for_size_p (DECL_STRUCT_FUNCTION (node->decl)))
continue;
}
- new_insns += growth;
+ 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);
- VARRAY_GENERIC_PTR_INIT (replace_trees, ipcp_const_param_count (node),
- "replace_trees");
- args_to_skip = BITMAP_ALLOC (NULL);
+ 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_lattice (info, i);
parm_tree = ipa_get_param (info, i);
/* We can proactively remove obviously unused arguments. */
- if (is_gimple_reg (parm_tree)
- && !gimple_default_def (DECL_STRUCT_FUNCTION (node->decl),
- parm_tree))
+ if (!ipa_is_param_used (info, i))
{
bitmap_set_bit (args_to_skip, i);
continue;
{
replace_param =
ipcp_create_replace_map (parm_tree, lat);
- VARRAY_PUSH_GENERIC_PTR (replace_trees, replace_param);
+ VEC_safe_push (ipa_replace_map_p, gc, replace_trees, replace_param);
bitmap_set_bit (args_to_skip, i);
}
}
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,
- args_to_skip);
- BITMAP_FREE (args_to_skip);
+ 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 with growth %i, overall %i\n",
- cgraph_node_name (node), (int)growth, (int)new_insns);
+ cgraph_node_name (node), (int)growth, (int)new_size);
ipcp_init_cloned_node (node, node1);
- /* We've possibly introduced direct calls. */
- ipcp_update_cloned_node (node1);
+ info = IPA_NODE_REF (node);
+ for (i = 0; i < count; i++)
+ {
+ struct ipcp_lattice *lat = ipcp_get_lattice (info, i);
+ if (lat->type == IPA_CONST_VALUE)
+ ipcp_discover_new_direct_edges (node1, i, lat->constant);
+ }
if (dump_file)
dump_function_to_file (node1->decl, dump_file, dump_flags);
ipcp_print_profile_data (dump_file);
}
/* Free all IPCP structures. */
- free_all_ipa_structures_after_ipa_cp ();
+ ipa_free_all_structures_after_ipa_cp ();
if (dump_file)
fprintf (dump_file, "\nIPA constant propagation end\n");
return 0;
}
-/* Note function body size. */
+/* 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 ();
- /* 1. Call the init stage to initialize
- the ipa_node_params and ipa_edge_args structures. */
- ipcp_init_stage ();
+
+ 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 ipa_opt_pass pass_ipa_cp =
+struct ipa_opt_pass_d pass_ipa_cp =
{
{
IPA_PASS,
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_remove_functions /* todo_flags_finish */
+ TODO_remove_functions | TODO_ggc_collect /* todo_flags_finish */
},
ipcp_generate_summary, /* generate_summary */
- NULL, /* write_summary */
- NULL, /* read_summary */
- NULL, /* function_read_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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