2009-09-08 Alexandre Oliva <aoliva@redhat.com>
+ * tree-ssa-loop-ivopts.c (get_phi_with_result): Remove.
+ (remove_statement): Likewise.
+ (rewrite_use_nonlinear_expr): Adjust.
+ (remove_unused_ivs): Collect SSA NAMEs to remove and call...
+ * tree-ssa.c (release_defs_bitset): ... this. New.
+ * tree-flow.h (release_defs_bitset): Declare.
+
+2009-09-08 Alexandre Oliva <aoliva@redhat.com>
+
PR debug/41232
* tree-ssa-phiopt.c (minmax_replacement): Skip debug stmts
in the middle block.
extern void walk_use_def_chains (tree, walk_use_def_chains_fn, void *, bool);
void propagate_defs_into_debug_stmts (gimple, basic_block,
- const gimple_stmt_iterator *);
+ const gimple_stmt_iterator *);
void propagate_var_def_into_debug_stmts (tree, basic_block,
- const gimple_stmt_iterator *);
+ const gimple_stmt_iterator *);
+void release_defs_bitset (bitmap toremove);
/* In tree-into-ssa.c */
void update_ssa (unsigned);
}
}
-/* Returns the phi-node in BB with result RESULT. */
-
-static gimple
-get_phi_with_result (basic_block bb, tree result)
-{
- gimple_stmt_iterator i = gsi_start_phis (bb);
-
- for (; !gsi_end_p (i); gsi_next (&i))
- if (gimple_phi_result (gsi_stmt (i)) == result)
- return gsi_stmt (i);
-
- gcc_unreachable ();
- return NULL;
-}
-
-
-/* Removes statement STMT (real or a phi node). If INCLUDING_DEFINED_NAME
- is true, remove also the ssa name defined by the statement. */
-
-static void
-remove_statement (gimple stmt, bool including_defined_name)
-{
- if (gimple_code (stmt) == GIMPLE_PHI)
- {
- gimple bb_phi = get_phi_with_result (gimple_bb (stmt),
- gimple_phi_result (stmt));
- gimple_stmt_iterator bsi = gsi_for_stmt (bb_phi);
- remove_phi_node (&bsi, including_defined_name);
- }
- else
- {
- gimple_stmt_iterator bsi = gsi_for_stmt (stmt);
- gsi_remove (&bsi, true);
- release_defs (stmt);
- }
-}
/* Rewrites USE (definition of iv used in a nonlinear expression)
using candidate CAND. */
{
ass = gimple_build_assign (tgt, op);
gsi_insert_before (&bsi, ass, GSI_SAME_STMT);
- remove_statement (use->stmt, false);
+
+ bsi = gsi_for_stmt (use->stmt);
+ remove_phi_node (&bsi, false);
}
else
{
{
unsigned j;
bitmap_iterator bi;
+ bitmap toremove = BITMAP_ALLOC (NULL);
+ /* Figure out an order in which to release SSA DEFs so that we don't
+ release something that we'd have to propagate into a debug stmt
+ afterwards. */
EXECUTE_IF_SET_IN_BITMAP (data->relevant, 0, j, bi)
{
struct version_info *info;
&& !info->inv_id
&& !info->iv->have_use_for
&& !info->preserve_biv)
- {
- if (MAY_HAVE_DEBUG_STMTS)
- {
- gimple stmt;
- imm_use_iterator iter;
-
- FOR_EACH_IMM_USE_STMT (stmt, iter, info->iv->ssa_name)
- {
- if (!gimple_debug_bind_p (stmt))
- continue;
-
- /* ??? We can probably do better than this. */
- gimple_debug_bind_reset_value (stmt);
- update_stmt (stmt);
- }
- }
- remove_statement (SSA_NAME_DEF_STMT (info->iv->ssa_name), true);
- }
+ bitmap_set_bit (toremove, SSA_NAME_VERSION (info->iv->ssa_name));
}
+
+ release_defs_bitset (toremove);
+
+ BITMAP_FREE (toremove);
}
/* Frees data allocated by the optimization of a single loop. */
}
}
+/* Delete SSA DEFs for SSA versions in the TOREMOVE bitmap, removing
+ dominated stmts before their dominators, so that release_ssa_defs
+ stands a chance of propagating DEFs into debug bind stmts. */
+
+void
+release_defs_bitset (bitmap toremove)
+{
+ unsigned j;
+ bitmap_iterator bi;
+
+ /* Performing a topological sort is probably overkill, this will
+ most likely run in slightly superlinear time, rather than the
+ pathological quadratic worst case. */
+ while (!bitmap_empty_p (toremove))
+ EXECUTE_IF_SET_IN_BITMAP (toremove, 0, j, bi)
+ {
+ bool remove_now = true;
+ tree var = ssa_name (j);
+ gimple stmt;
+ imm_use_iterator uit;
+
+ FOR_EACH_IMM_USE_STMT (stmt, uit, var)
+ {
+ ssa_op_iter dit;
+ def_operand_p def_p;
+
+ /* We can't propagate PHI nodes into debug stmts. */
+ if (gimple_code (stmt) == GIMPLE_PHI
+ || is_gimple_debug (stmt))
+ continue;
+
+ /* If we find another definition to remove that uses
+ the one we're looking at, defer the removal of this
+ one, so that it can be propagated into debug stmts
+ after the other is. */
+ FOR_EACH_SSA_DEF_OPERAND (def_p, stmt, dit, SSA_OP_DEF)
+ {
+ tree odef = DEF_FROM_PTR (def_p);
+
+ if (bitmap_bit_p (toremove, SSA_NAME_VERSION (odef)))
+ {
+ remove_now = false;
+ break;
+ }
+ }
+
+ if (!remove_now)
+ BREAK_FROM_IMM_USE_STMT (uit);
+ }
+
+ if (remove_now)
+ {
+ gimple def = SSA_NAME_DEF_STMT (var);
+ gimple_stmt_iterator gsi = gsi_for_stmt (def);
+
+ if (gimple_code (def) == GIMPLE_PHI)
+ remove_phi_node (&gsi, true);
+ else
+ {
+ gsi_remove (&gsi, true);
+ release_defs (def);
+ }
+
+ bitmap_clear_bit (toremove, j);
+ }
+ }
+}
+
/* Return true if SSA_NAME is malformed and mark it visited.
IS_VIRTUAL is true if this SSA_NAME was found inside a virtual
OSDN Git Service
