/* Generic routines for manipulating SSA_NAME expressions
- Copyright (C) 2003, 2004, 2005, 2007, 2008, 2009
- Free Software Foundation, Inc.
+ Copyright (C) 2003-2016 Free Software Foundation, Inc.
This file is part of GCC.
#include "config.h"
#include "system.h"
#include "coretypes.h"
-#include "tm.h"
+#include "backend.h"
#include "tree.h"
-#include "ggc.h"
-#include "tree-flow.h"
+#include "gimple.h"
#include "tree-pass.h"
+#include "ssa.h"
+#include "gimple-iterator.h"
+#include "stor-layout.h"
+#include "tree-into-ssa.h"
+#include "tree-ssa.h"
/* Rewriting a function into SSA form can create a huge number of SSA_NAMEs,
many of which may be thrown away shortly after their creation if jumps
External code should also not assume the version number on nodes is
monotonically increasing. We reuse the version number when we
reuse an SSA_NAME expression. This helps keep arrays and bitmaps
- more compact.
+ more compact. */
- We could also use a zone allocator for these objects since they have
- a very well defined lifetime. If someone wants to experiment with that
- this is the place to try it. */
/* Version numbers with special meanings. We start allocating new version
numbers after the special ones. */
#define UNUSED_NAME_VERSION 0
-#ifdef GATHER_STATISTICS
unsigned int ssa_name_nodes_reused;
unsigned int ssa_name_nodes_created;
-#endif
+
+#define FREE_SSANAMES(fun) (fun)->gimple_df->free_ssanames
+#define FREE_SSANAMES_QUEUE(fun) (fun)->gimple_df->free_ssanames_queue
+
/* Initialize management of SSA_NAMEs to default SIZE. If SIZE is
zero use default. */
if (size < 50)
size = 50;
- SSANAMES (fn) = VEC_alloc (tree, gc, size);
+ vec_alloc (SSANAMES (fn), size);
/* Version 0 is special, so reserve the first slot in the table. Though
currently unused, we may use version 0 in alias analysis as part of
the heuristics used to group aliases when the alias sets are too
large.
- We use VEC_quick_push here because we know that SSA_NAMES has at
+ We use vec::quick_push here because we know that SSA_NAMES has at
least 50 elements reserved in it. */
- VEC_quick_push (tree, SSANAMES (fn), NULL_TREE);
+ SSANAMES (fn)->quick_push (NULL_TREE);
FREE_SSANAMES (fn) = NULL;
+ FREE_SSANAMES_QUEUE (fn) = NULL;
- SYMS_TO_RENAME (fn) = BITMAP_GGC_ALLOC ();
+ fn->gimple_df->ssa_renaming_needed = 0;
+ fn->gimple_df->rename_vops = 0;
}
/* Finalize management of SSA_NAMEs. */
void
-fini_ssanames (void)
+fini_ssanames (struct function *fn)
{
- VEC_free (tree, gc, SSANAMES (cfun));
- FREE_SSANAMES (cfun) = NULL;
+ vec_free (SSANAMES (fn));
+ vec_free (FREE_SSANAMES (fn));
+ vec_free (FREE_SSANAMES_QUEUE (fn));
}
/* Dump some simple statistics regarding the re-use of SSA_NAME nodes. */
-#ifdef GATHER_STATISTICS
void
ssanames_print_statistics (void)
{
fprintf (stderr, "SSA_NAME nodes allocated: %u\n", ssa_name_nodes_created);
fprintf (stderr, "SSA_NAME nodes reused: %u\n", ssa_name_nodes_reused);
}
-#endif
+
+/* Verify the state of the SSA_NAME lists.
+
+ There must be no duplicates on the free list.
+ Every name on the free list must be marked as on the free list.
+ Any name on the free list must not appear in the IL.
+ No names can be leaked. */
+
+DEBUG_FUNCTION void
+verify_ssaname_freelists (struct function *fun)
+{
+ if (!gimple_in_ssa_p (fun))
+ return;
+
+ bitmap names_in_il = BITMAP_ALLOC (NULL);
+
+ /* Walk the entire IL noting every SSA_NAME we see. */
+ basic_block bb;
+ FOR_EACH_BB_FN (bb, fun)
+ {
+ tree t;
+ /* First note the result and arguments of PHI nodes. */
+ for (gphi_iterator gsi = gsi_start_phis (bb);
+ !gsi_end_p (gsi);
+ gsi_next (&gsi))
+ {
+ gphi *phi = gsi.phi ();
+ t = gimple_phi_result (phi);
+ bitmap_set_bit (names_in_il, SSA_NAME_VERSION (t));
+
+ for (unsigned int i = 0; i < gimple_phi_num_args (phi); i++)
+ {
+ t = gimple_phi_arg_def (phi, i);
+ if (TREE_CODE (t) == SSA_NAME)
+ bitmap_set_bit (names_in_il, SSA_NAME_VERSION (t));
+ }
+ }
+
+ /* Then note the operands of each statement. */
+ for (gimple_stmt_iterator gsi = gsi_start_bb (bb);
+ !gsi_end_p (gsi);
+ gsi_next (&gsi))
+ {
+ ssa_op_iter iter;
+ gimple *stmt = gsi_stmt (gsi);
+ FOR_EACH_SSA_TREE_OPERAND (t, stmt, iter, SSA_OP_ALL_OPERANDS)
+ bitmap_set_bit (names_in_il, SSA_NAME_VERSION (t));
+ }
+ }
+
+ /* Now walk the free list noting what we find there and verifying
+ there are no duplicates. */
+ bitmap names_in_freelists = BITMAP_ALLOC (NULL);
+ if (FREE_SSANAMES (fun))
+ {
+ for (unsigned int i = 0; i < FREE_SSANAMES (fun)->length (); i++)
+ {
+ tree t = (*FREE_SSANAMES (fun))[i];
+
+ /* Verify that the name is marked as being in the free list. */
+ gcc_assert (SSA_NAME_IN_FREE_LIST (t));
+
+ /* Verify the name has not already appeared in the free list and
+ note it in the list of names found in the free list. */
+ gcc_assert (!bitmap_bit_p (names_in_freelists, SSA_NAME_VERSION (t)));
+ bitmap_set_bit (names_in_freelists, SSA_NAME_VERSION (t));
+ }
+ }
+
+ /* Similarly for the names in the pending free list. */
+ if (FREE_SSANAMES_QUEUE (fun))
+ {
+ for (unsigned int i = 0; i < FREE_SSANAMES_QUEUE (fun)->length (); i++)
+ {
+ tree t = (*FREE_SSANAMES_QUEUE (fun))[i];
+
+ /* Verify that the name is marked as being in the free list. */
+ gcc_assert (SSA_NAME_IN_FREE_LIST (t));
+
+ /* Verify the name has not already appeared in the free list and
+ note it in the list of names found in the free list. */
+ gcc_assert (!bitmap_bit_p (names_in_freelists, SSA_NAME_VERSION (t)));
+ bitmap_set_bit (names_in_freelists, SSA_NAME_VERSION (t));
+ }
+ }
+
+ /* If any name appears in both the IL and the freelists, then
+ something horrible has happened. */
+ bool intersect_p = bitmap_intersect_p (names_in_il, names_in_freelists);
+ gcc_assert (!intersect_p);
+
+ /* Names can be queued up for release if there is an ssa update
+ pending. Pretend we saw them in the IL. */
+ if (names_to_release)
+ bitmap_ior_into (names_in_il, names_to_release);
+
+ /* Function splitting can "lose" SSA_NAMEs in an effort to ensure that
+ debug/non-debug compilations have the same SSA_NAMEs. So for each
+ lost SSA_NAME, see if it's likely one from that wart. These will always
+ be marked as default definitions. So we loosely assume that anything
+ marked as a default definition isn't leaked by pretending they are
+ in the IL. */
+ for (unsigned int i = UNUSED_NAME_VERSION + 1; i < num_ssa_names; i++)
+ if (ssa_name (i) && SSA_NAME_IS_DEFAULT_DEF (ssa_name (i)))
+ bitmap_set_bit (names_in_il, i);
+
+ unsigned int i;
+ bitmap_iterator bi;
+ bitmap all_names = BITMAP_ALLOC (NULL);
+ bitmap_set_range (all_names, UNUSED_NAME_VERSION + 1, num_ssa_names - 1);
+ bitmap_ior_into (names_in_il, names_in_freelists);
+
+ /* Any name not mentioned in the IL and not in the feelists
+ has been leaked. */
+ EXECUTE_IF_AND_COMPL_IN_BITMAP(all_names, names_in_il,
+ UNUSED_NAME_VERSION + 1, i, bi)
+ gcc_assert (!ssa_name (i));
+
+ BITMAP_FREE (all_names);
+ BITMAP_FREE (names_in_freelists);
+ BITMAP_FREE (names_in_il);
+}
+
+/* Move all SSA_NAMEs from FREE_SSA_NAMES_QUEUE to FREE_SSA_NAMES.
+
+ We do not, but should have a mode to verify the state of the SSA_NAMEs
+ lists. In particular at this point every name must be in the IL,
+ on the free list or in the queue. Anything else is an error. */
+
+void
+flush_ssaname_freelist (void)
+{
+ vec_safe_splice (FREE_SSANAMES (cfun), FREE_SSANAMES_QUEUE (cfun));
+ vec_safe_truncate (FREE_SSANAMES_QUEUE (cfun), 0);
+}
/* Return an SSA_NAME node for variable VAR defined in statement STMT
in function FN. STMT may be an empty statement for artificial
used without a preceding definition). */
tree
-make_ssa_name_fn (struct function *fn, tree var, gimple stmt)
+make_ssa_name_fn (struct function *fn, tree var, gimple *stmt)
{
tree t;
use_operand_p imm;
- gcc_assert (DECL_P (var));
+ gcc_assert (TREE_CODE (var) == VAR_DECL
+ || TREE_CODE (var) == PARM_DECL
+ || TREE_CODE (var) == RESULT_DECL
+ || (TYPE_P (var) && is_gimple_reg_type (var)));
/* If our free list has an element, then use it. */
- if (FREE_SSANAMES (fn))
+ if (!vec_safe_is_empty (FREE_SSANAMES (fn)))
{
- t = FREE_SSANAMES (fn);
- FREE_SSANAMES (fn) = TREE_CHAIN (FREE_SSANAMES (fn));
-#ifdef GATHER_STATISTICS
+ t = FREE_SSANAMES (fn)->pop ();
ssa_name_nodes_reused++;
-#endif
/* The node was cleared out when we put it on the free list, so
there is no need to do so again here. */
- gcc_assert (ssa_name (SSA_NAME_VERSION (t)) == NULL);
- VEC_replace (tree, SSANAMES (fn), SSA_NAME_VERSION (t), t);
+ gcc_assert ((*SSANAMES (fn))[SSA_NAME_VERSION (t)] == NULL);
+ (*SSANAMES (fn))[SSA_NAME_VERSION (t)] = t;
}
else
{
t = make_node (SSA_NAME);
- SSA_NAME_VERSION (t) = VEC_length (tree, SSANAMES (fn));
- VEC_safe_push (tree, gc, SSANAMES (fn), t);
-#ifdef GATHER_STATISTICS
+ SSA_NAME_VERSION (t) = SSANAMES (fn)->length ();
+ vec_safe_push (SSANAMES (fn), t);
ssa_name_nodes_created++;
-#endif
}
- TREE_TYPE (t) = TREE_TYPE (var);
- SSA_NAME_VAR (t) = var;
+ if (TYPE_P (var))
+ {
+ TREE_TYPE (t) = var;
+ SET_SSA_NAME_VAR_OR_IDENTIFIER (t, NULL_TREE);
+ }
+ else
+ {
+ TREE_TYPE (t) = TREE_TYPE (var);
+ SET_SSA_NAME_VAR_OR_IDENTIFIER (t, var);
+ }
SSA_NAME_DEF_STMT (t) = stmt;
- SSA_NAME_PTR_INFO (t) = NULL;
+ if (POINTER_TYPE_P (TREE_TYPE (t)))
+ SSA_NAME_PTR_INFO (t) = NULL;
+ else
+ SSA_NAME_RANGE_INFO (t) = NULL;
+
SSA_NAME_IN_FREE_LIST (t) = 0;
SSA_NAME_IS_DEFAULT_DEF (t) = 0;
imm = &(SSA_NAME_IMM_USE_NODE (t));
return t;
}
+/* Store range information RANGE_TYPE, MIN, and MAX to tree ssa_name NAME. */
+
+void
+set_range_info (tree name, enum value_range_type range_type,
+ const wide_int_ref &min, const wide_int_ref &max)
+{
+ gcc_assert (!POINTER_TYPE_P (TREE_TYPE (name)));
+ gcc_assert (range_type == VR_RANGE || range_type == VR_ANTI_RANGE);
+ range_info_def *ri = SSA_NAME_RANGE_INFO (name);
+ unsigned int precision = TYPE_PRECISION (TREE_TYPE (name));
+
+ /* Allocate if not available. */
+ if (ri == NULL)
+ {
+ size_t size = (sizeof (range_info_def)
+ + trailing_wide_ints <3>::extra_size (precision));
+ ri = static_cast<range_info_def *> (ggc_internal_alloc (size));
+ ri->ints.set_precision (precision);
+ SSA_NAME_RANGE_INFO (name) = ri;
+ ri->set_nonzero_bits (wi::shwi (-1, precision));
+ }
+
+ /* Record the range type. */
+ if (SSA_NAME_RANGE_TYPE (name) != range_type)
+ SSA_NAME_ANTI_RANGE_P (name) = (range_type == VR_ANTI_RANGE);
+
+ /* Set the values. */
+ ri->set_min (min);
+ ri->set_max (max);
+
+ /* If it is a range, try to improve nonzero_bits from the min/max. */
+ if (range_type == VR_RANGE)
+ {
+ wide_int xorv = ri->get_min () ^ ri->get_max ();
+ if (xorv != 0)
+ xorv = wi::mask (precision - wi::clz (xorv), false, precision);
+ ri->set_nonzero_bits (ri->get_nonzero_bits () & (ri->get_min () | xorv));
+ }
+}
+
+
+/* Gets range information MIN, MAX and returns enum value_range_type
+ corresponding to tree ssa_name NAME. enum value_range_type returned
+ is used to determine if MIN and MAX are valid values. */
+
+enum value_range_type
+get_range_info (const_tree name, wide_int *min, wide_int *max)
+{
+ gcc_assert (!POINTER_TYPE_P (TREE_TYPE (name)));
+ gcc_assert (min && max);
+ range_info_def *ri = SSA_NAME_RANGE_INFO (name);
+
+ /* Return VR_VARYING for SSA_NAMEs with NULL RANGE_INFO or SSA_NAMEs
+ with integral types width > 2 * HOST_BITS_PER_WIDE_INT precision. */
+ if (!ri || (GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (name)))
+ > 2 * HOST_BITS_PER_WIDE_INT))
+ return VR_VARYING;
+
+ *min = ri->get_min ();
+ *max = ri->get_max ();
+ return SSA_NAME_RANGE_TYPE (name);
+}
+
+/* Change non-zero bits bitmask of NAME. */
+
+void
+set_nonzero_bits (tree name, const wide_int_ref &mask)
+{
+ gcc_assert (!POINTER_TYPE_P (TREE_TYPE (name)));
+ if (SSA_NAME_RANGE_INFO (name) == NULL)
+ set_range_info (name, VR_RANGE,
+ TYPE_MIN_VALUE (TREE_TYPE (name)),
+ TYPE_MAX_VALUE (TREE_TYPE (name)));
+ range_info_def *ri = SSA_NAME_RANGE_INFO (name);
+ ri->set_nonzero_bits (mask);
+}
+
+/* Return a widest_int with potentially non-zero bits in SSA_NAME
+ NAME, or -1 if unknown. */
+
+wide_int
+get_nonzero_bits (const_tree name)
+{
+ unsigned int precision = TYPE_PRECISION (TREE_TYPE (name));
+ if (POINTER_TYPE_P (TREE_TYPE (name)))
+ {
+ struct ptr_info_def *pi = SSA_NAME_PTR_INFO (name);
+ if (pi && pi->align)
+ return wi::shwi (-(HOST_WIDE_INT) pi->align
+ | (HOST_WIDE_INT) pi->misalign, precision);
+ return wi::shwi (-1, precision);
+ }
+
+ range_info_def *ri = SSA_NAME_RANGE_INFO (name);
+ if (!ri)
+ return wi::shwi (-1, precision);
+
+ return ri->get_nonzero_bits ();
+}
/* We no longer need the SSA_NAME expression VAR, release it so that
it may be reused.
other fields must be assumed clobbered. */
void
-release_ssa_name (tree var)
+release_ssa_name_fn (struct function *fn, tree var)
{
if (!var)
return;
if (MAY_HAVE_DEBUG_STMTS)
insert_debug_temp_for_var_def (NULL, var);
-#ifdef ENABLE_CHECKING
- verify_imm_links (stderr, var);
-#endif
+ if (flag_checking)
+ verify_imm_links (stderr, var);
while (imm->next != imm)
delink_imm_use (imm->next);
- VEC_replace (tree, SSANAMES (cfun),
- SSA_NAME_VERSION (var), NULL_TREE);
+ (*SSANAMES (fn))[SSA_NAME_VERSION (var)] = NULL_TREE;
memset (var, 0, tree_size (var));
imm->prev = imm;
/* Hopefully this can go away once we have the new incremental
SSA updating code installed. */
- SSA_NAME_VAR (var) = saved_ssa_name_var;
+ SET_SSA_NAME_VAR_OR_IDENTIFIER (var, saved_ssa_name_var);
/* Note this SSA_NAME is now in the first list. */
SSA_NAME_IN_FREE_LIST (var) = 1;
- /* And finally link it into the free list. */
- TREE_CHAIN (var) = FREE_SSANAMES (cfun);
- FREE_SSANAMES (cfun) = var;
+ /* And finally queue it so that it will be put on the free list. */
+ vec_safe_push (FREE_SSANAMES_QUEUE (fn), var);
+ }
+}
+
+/* If the alignment of the pointer described by PI is known, return true and
+ store the alignment and the deviation from it into *ALIGNP and *MISALIGNP
+ respectively. Otherwise return false. */
+
+bool
+get_ptr_info_alignment (struct ptr_info_def *pi, unsigned int *alignp,
+ unsigned int *misalignp)
+{
+ if (pi->align)
+ {
+ *alignp = pi->align;
+ *misalignp = pi->misalign;
+ return true;
+ }
+ else
+ return false;
+}
+
+/* State that the pointer described by PI has unknown alignment. */
+
+void
+mark_ptr_info_alignment_unknown (struct ptr_info_def *pi)
+{
+ pi->align = 0;
+ pi->misalign = 0;
+}
+
+/* Store the power-of-two byte alignment and the deviation from that
+ alignment of pointer described by PI to ALIOGN and MISALIGN
+ respectively. */
+
+void
+set_ptr_info_alignment (struct ptr_info_def *pi, unsigned int align,
+ unsigned int misalign)
+{
+ gcc_checking_assert (align != 0);
+ gcc_assert ((align & (align - 1)) == 0);
+ gcc_assert ((misalign & ~(align - 1)) == 0);
+
+ pi->align = align;
+ pi->misalign = misalign;
+}
+
+/* If pointer described by PI has known alignment, increase its known
+ misalignment by INCREMENT modulo its current alignment. */
+
+void
+adjust_ptr_info_misalignment (struct ptr_info_def *pi,
+ unsigned int increment)
+{
+ if (pi->align != 0)
+ {
+ pi->misalign += increment;
+ pi->misalign &= (pi->align - 1);
}
}
-/* Creates a duplicate of a ssa name NAME defined in statement STMT. */
+/* Return the alias information associated with pointer T. It creates a
+ new instance if none existed. */
+
+struct ptr_info_def *
+get_ptr_info (tree t)
+{
+ struct ptr_info_def *pi;
+
+ gcc_assert (POINTER_TYPE_P (TREE_TYPE (t)));
+
+ pi = SSA_NAME_PTR_INFO (t);
+ if (pi == NULL)
+ {
+ pi = ggc_cleared_alloc<ptr_info_def> ();
+ pt_solution_reset (&pi->pt);
+ mark_ptr_info_alignment_unknown (pi);
+ SSA_NAME_PTR_INFO (t) = pi;
+ }
+
+ return pi;
+}
+
+
+/* Creates a new SSA name using the template NAME tobe defined by
+ statement STMT in function FN. */
tree
-duplicate_ssa_name (tree name, gimple stmt)
+copy_ssa_name_fn (struct function *fn, tree name, gimple *stmt)
{
- tree new_name = make_ssa_name (SSA_NAME_VAR (name), stmt);
- struct ptr_info_def *old_ptr_info = SSA_NAME_PTR_INFO (name);
+ tree new_name;
- if (old_ptr_info)
- duplicate_ssa_name_ptr_info (new_name, old_ptr_info);
+ if (SSA_NAME_VAR (name))
+ new_name = make_ssa_name_fn (fn, SSA_NAME_VAR (name), stmt);
+ else
+ {
+ new_name = make_ssa_name_fn (fn, TREE_TYPE (name), stmt);
+ SET_SSA_NAME_VAR_OR_IDENTIFIER (new_name, SSA_NAME_IDENTIFIER (name));
+ }
return new_name;
}
if (!ptr_info)
return;
- new_ptr_info = GGC_NEW (struct ptr_info_def);
+ new_ptr_info = ggc_alloc<ptr_info_def> ();
*new_ptr_info = *ptr_info;
SSA_NAME_PTR_INFO (name) = new_ptr_info;
}
+/* Creates a duplicate of the range_info_def at RANGE_INFO of type
+ RANGE_TYPE for use by the SSA name NAME. */
+void
+duplicate_ssa_name_range_info (tree name, enum value_range_type range_type,
+ struct range_info_def *range_info)
+{
+ struct range_info_def *new_range_info;
+
+ gcc_assert (!POINTER_TYPE_P (TREE_TYPE (name)));
+ gcc_assert (!SSA_NAME_RANGE_INFO (name));
+
+ if (!range_info)
+ return;
+
+ unsigned int precision = TYPE_PRECISION (TREE_TYPE (name));
+ size_t size = (sizeof (range_info_def)
+ + trailing_wide_ints <3>::extra_size (precision));
+ new_range_info = static_cast<range_info_def *> (ggc_internal_alloc (size));
+ memcpy (new_range_info, range_info, size);
+
+ gcc_assert (range_type == VR_RANGE || range_type == VR_ANTI_RANGE);
+ SSA_NAME_ANTI_RANGE_P (name) = (range_type == VR_ANTI_RANGE);
+ SSA_NAME_RANGE_INFO (name) = new_range_info;
+}
+
+
+
+/* Creates a duplicate of a ssa name NAME tobe defined by statement STMT
+ in function FN. */
+
+tree
+duplicate_ssa_name_fn (struct function *fn, tree name, gimple *stmt)
+{
+ tree new_name = copy_ssa_name_fn (fn, name, stmt);
+ if (POINTER_TYPE_P (TREE_TYPE (name)))
+ {
+ struct ptr_info_def *old_ptr_info = SSA_NAME_PTR_INFO (name);
+
+ if (old_ptr_info)
+ duplicate_ssa_name_ptr_info (new_name, old_ptr_info);
+ }
+ else
+ {
+ struct range_info_def *old_range_info = SSA_NAME_RANGE_INFO (name);
+
+ if (old_range_info)
+ duplicate_ssa_name_range_info (new_name, SSA_NAME_RANGE_TYPE (name),
+ old_range_info);
+ }
+
+ return new_name;
+}
+
+
+/* Reset all flow sensitive data on NAME such as range-info, nonzero
+ bits and alignment. */
+
+void
+reset_flow_sensitive_info (tree name)
+{
+ if (POINTER_TYPE_P (TREE_TYPE (name)))
+ {
+ /* points-to info is not flow-sensitive. */
+ if (SSA_NAME_PTR_INFO (name))
+ mark_ptr_info_alignment_unknown (SSA_NAME_PTR_INFO (name));
+ }
+ else
+ SSA_NAME_RANGE_INFO (name) = NULL;
+}
+
+/* Clear all flow sensitive data from all statements and PHI definitions
+ in BB. */
+
+void
+reset_flow_sensitive_info_in_bb (basic_block bb)
+{
+ for (gimple_stmt_iterator gsi = gsi_start_bb (bb); !gsi_end_p (gsi);
+ gsi_next (&gsi))
+ {
+ gimple *stmt = gsi_stmt (gsi);
+ ssa_op_iter i;
+ tree op;
+ FOR_EACH_SSA_TREE_OPERAND (op, stmt, i, SSA_OP_DEF)
+ reset_flow_sensitive_info (op);
+ }
+
+ for (gphi_iterator gsi = gsi_start_phis (bb); !gsi_end_p (gsi);
+ gsi_next (&gsi))
+ {
+ tree phi_def = gimple_phi_result (gsi.phi ());
+ reset_flow_sensitive_info (phi_def);
+ }
+}
/* Release all the SSA_NAMEs created by STMT. */
void
-release_defs (gimple stmt)
+release_defs (gimple *stmt)
{
tree def;
ssa_op_iter iter;
void
replace_ssa_name_symbol (tree ssa_name, tree sym)
{
- SSA_NAME_VAR (ssa_name) = sym;
+ SET_SSA_NAME_VAR_OR_IDENTIFIER (ssa_name, sym);
TREE_TYPE (ssa_name) = TREE_TYPE (sym);
}
-/* Return SSA names that are unused to GGC memory. This is used to keep
- footprint of compiler during interprocedural optimization.
- As a side effect the SSA_NAME_VERSION number reuse is reduced
- so this function should not be used too often. */
-static unsigned int
-release_dead_ssa_names (void)
+/* Release the vector of free SSA_NAMEs and compact the the
+ vector of SSA_NAMEs that are live. */
+
+static void
+release_free_names_and_compact_live_names (function *fun)
{
- tree t, next;
- int n = 0;
- referenced_var_iterator rvi;
-
- /* Current defs point to various dead SSA names that in turn points to dead
- statements so bunch of dead memory is held from releasing. */
- FOR_EACH_REFERENCED_VAR (t, rvi)
- set_current_def (t, NULL);
+ unsigned i, j;
+ int n = vec_safe_length (FREE_SSANAMES (fun));
+
/* Now release the freelist. */
- for (t = FREE_SSANAMES (cfun); t; t = next)
+ vec_free (FREE_SSANAMES (fun));
+
+ /* And compact the SSA number space. We make sure to not change the
+ relative order of SSA versions. */
+ for (i = 1, j = 1; i < fun->gimple_df->ssa_names->length (); ++i)
{
- next = TREE_CHAIN (t);
- /* Dangling pointers might make GGC to still see dead SSA names, so it is
- important to unlink the list and avoid GGC from seeing all subsequent
- SSA names. In longer run we want to have all dangling pointers here
- removed (since they usually go through dead statements that consume
- considerable amounts of memory). */
- TREE_CHAIN (t) = NULL_TREE;
- n++;
+ tree name = ssa_name (i);
+ if (name)
+ {
+ if (i != j)
+ {
+ SSA_NAME_VERSION (name) = j;
+ (*fun->gimple_df->ssa_names)[j] = name;
+ }
+ j++;
+ }
}
- FREE_SSANAMES (cfun) = NULL;
-
- /* Cgraph edges has been invalidated and point to dead statement. We need to
- remove them now and will rebuild it before next IPA pass. */
- cgraph_node_remove_callees (cgraph_node (current_function_decl));
+ fun->gimple_df->ssa_names->truncate (j);
+ statistics_counter_event (fun, "SSA names released", n);
+ statistics_counter_event (fun, "SSA name holes removed", i - j);
if (dump_file)
- fprintf (dump_file, "Released %i names, %.2f%%\n", n, n * 100.0 / num_ssa_names);
- return 0;
+ fprintf (dump_file, "Released %i names, %.2f%%, removed %i holes\n",
+ n, n * 100.0 / num_ssa_names, i - j);
}
-struct gimple_opt_pass pass_release_ssa_names =
+/* Return SSA names that are unused to GGC memory and compact the SSA
+ version namespace. This is used to keep footprint of compiler during
+ interprocedural optimization. */
+
+namespace {
+
+const pass_data pass_data_release_ssa_names =
{
- {
- GIMPLE_PASS,
- "release_ssa", /* name */
- NULL, /* gate */
- release_dead_ssa_names, /* execute */
- NULL, /* sub */
- NULL, /* next */
- 0, /* static_pass_number */
- TV_NONE, /* tv_id */
- PROP_ssa, /* properties_required */
- 0, /* properties_provided */
- 0, /* properties_destroyed */
- 0, /* todo_flags_start */
- TODO_dump_func /* todo_flags_finish */
- }
+ GIMPLE_PASS, /* type */
+ "release_ssa", /* name */
+ OPTGROUP_NONE, /* optinfo_flags */
+ TV_TREE_SSA_OTHER, /* tv_id */
+ PROP_ssa, /* properties_required */
+ 0, /* properties_provided */
+ 0, /* properties_destroyed */
+ TODO_remove_unused_locals, /* todo_flags_start */
+ 0, /* todo_flags_finish */
};
+
+class pass_release_ssa_names : public gimple_opt_pass
+{
+public:
+ pass_release_ssa_names (gcc::context *ctxt)
+ : gimple_opt_pass (pass_data_release_ssa_names, ctxt)
+ {}
+
+ /* opt_pass methods: */
+ virtual unsigned int execute (function *);
+
+}; // class pass_release_ssa_names
+
+unsigned int
+pass_release_ssa_names::execute (function *fun)
+{
+ release_free_names_and_compact_live_names (fun);
+ return 0;
+}
+
+} // anon namespace
+
+gimple_opt_pass *
+make_pass_release_ssa_names (gcc::context *ctxt)
+{
+ return new pass_release_ssa_names (ctxt);
+}
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