#include "system.h"
#include "coretypes.h"
#include "tm.h"
-#include "hash-set.h"
-#include "machmode.h"
-#include "vec.h"
-#include "double-int.h"
-#include "input.h"
#include "alias.h"
#include "symtab.h"
-#include "wide-int.h"
-#include "inchash.h"
-#include "real.h"
#include "tree.h"
#include "fold-const.h"
#include "stor-layout.h"
#include "tm_p.h"
#include "predict.h"
#include "hard-reg-set.h"
-#include "input.h"
#include "function.h"
#include "dominance.h"
#include "cfg.h"
#include "basic-block.h"
#include "gimple-pretty-print.h"
-#include "hash-table.h"
#include "tree-ssa-alias.h"
#include "internal-fn.h"
#include "gimple-fold.h"
#include "tree-eh.h"
#include "gimple-expr.h"
-#include "is-a.h"
#include "gimple.h"
#include "gimplify.h"
#include "gimple-iterator.h"
static void canonicalize_value (ccp_prop_value_t *);
static bool ccp_fold_stmt (gimple_stmt_iterator *);
+static void ccp_lattice_meet (ccp_prop_value_t *, ccp_prop_value_t *);
/* Dump constant propagation value VAL to file OUTF prefixed by PREFIX. */
value is different from VAR's previous value. */
static bool
-set_lattice_value (tree var, ccp_prop_value_t new_val)
+set_lattice_value (tree var, ccp_prop_value_t *new_val)
{
/* We can deal with old UNINITIALIZED values just fine here. */
ccp_prop_value_t *old_val = &const_val[SSA_NAME_VERSION (var)];
- canonicalize_value (&new_val);
+ canonicalize_value (new_val);
/* We have to be careful to not go up the bitwise lattice
- represented by the mask.
- ??? This doesn't seem to be the best place to enforce this. */
- if (new_val.lattice_val == CONSTANT
+ represented by the mask. Instead of dropping to VARYING
+ use the meet operator to retain a conservative value.
+ Missed optimizations like PR65851 makes this necessary.
+ It also ensures we converge to a stable lattice solution. */
+ if (new_val->lattice_val == CONSTANT
&& old_val->lattice_val == CONSTANT
- && TREE_CODE (new_val.value) == INTEGER_CST
- && TREE_CODE (old_val->value) == INTEGER_CST)
- {
- widest_int diff = (wi::to_widest (new_val.value)
- ^ wi::to_widest (old_val->value));
- new_val.mask = new_val.mask | old_val->mask | diff;
- }
+ && TREE_CODE (new_val->value) != SSA_NAME)
+ ccp_lattice_meet (new_val, old_val);
- gcc_checking_assert (valid_lattice_transition (*old_val, new_val));
+ gcc_checking_assert (valid_lattice_transition (*old_val, *new_val));
/* If *OLD_VAL and NEW_VAL are the same, return false to inform the
caller that this was a non-transition. */
- if (old_val->lattice_val != new_val.lattice_val
- || (new_val.lattice_val == CONSTANT
- && (TREE_CODE (new_val.value) != TREE_CODE (old_val->value)
- || simple_cst_equal (new_val.value, old_val->value) != 1
- || (TREE_CODE (new_val.value) == INTEGER_CST
- && new_val.mask != old_val->mask))))
+ if (old_val->lattice_val != new_val->lattice_val
+ || (new_val->lattice_val == CONSTANT
+ && (TREE_CODE (new_val->value) != TREE_CODE (old_val->value)
+ || (TREE_CODE (new_val->value) == INTEGER_CST
+ && (new_val->mask != old_val->mask
+ || (wi::bit_and_not (wi::to_widest (old_val->value),
+ new_val->mask)
+ != wi::bit_and_not (wi::to_widest (new_val->value),
+ new_val->mask))))
+ || (TREE_CODE (new_val->value) != INTEGER_CST
+ && !operand_equal_p (new_val->value, old_val->value, 0)))))
{
/* ??? We would like to delay creation of INTEGER_CSTs from
partially constants here. */
if (dump_file && (dump_flags & TDF_DETAILS))
{
- dump_lattice_value (dump_file, "Lattice value changed to ", new_val);
+ dump_lattice_value (dump_file, "Lattice value changed to ", *new_val);
fprintf (dump_file, ". Adding SSA edges to worklist.\n");
}
- *old_val = new_val;
+ *old_val = *new_val;
- gcc_assert (new_val.lattice_val != UNINITIALIZED);
+ gcc_assert (new_val->lattice_val != UNINITIALIZED);
return true;
}
&& val.lattice_val == CONSTANT
&& TREE_CODE (val.value) == ADDR_EXPR)
val = get_value_from_alignment (val.value);
+ /* Fall back to a copy value. */
+ if (!for_bits_p
+ && val.lattice_val == VARYING
+ && !SSA_NAME_OCCURS_IN_ABNORMAL_PHI (expr))
+ {
+ val.lattice_val = CONSTANT;
+ val.value = expr;
+ val.mask = -1;
+ }
}
else if (is_gimple_min_invariant (expr)
&& (!for_bits_p || TREE_CODE (expr) != ADDR_EXPR))
*/
static void
-ccp_lattice_meet (basic_block where,
- ccp_prop_value_t *val1, ccp_prop_value_t *val2)
+ccp_lattice_meet (ccp_prop_value_t *val1, ccp_prop_value_t *val2)
{
if (val1->lattice_val == UNDEFINED
/* For UNDEFINED M SSA we can't always SSA because its definition
}
else if (val1->lattice_val == CONSTANT
&& val2->lattice_val == CONSTANT
- && simple_cst_equal (val1->value, val2->value) == 1)
+ && operand_equal_p (val1->value, val2->value, 0))
{
/* Ci M Cj = Ci if (i == j)
Ci M Cj = VARYING if (i != j)
*val1 = get_value_for_expr (val1->value, true);
if (TREE_CODE (val2->value) == ADDR_EXPR)
tem = get_value_for_expr (val2->value, true);
- ccp_lattice_meet (where, val1, &tem);
+ ccp_lattice_meet (val1, &tem);
}
else
{
ccp_visit_phi_node (gphi *phi)
{
unsigned i;
- ccp_prop_value_t *old_val, new_val;
+ ccp_prop_value_t new_val;
if (dump_file && (dump_flags & TDF_DETAILS))
{
print_gimple_stmt (dump_file, phi, 0, dump_flags);
}
- old_val = get_value (gimple_phi_result (phi));
- switch (old_val->lattice_val)
- {
- case VARYING:
- return SSA_PROP_VARYING;
-
- case CONSTANT:
- new_val = *old_val;
- break;
-
- case UNDEFINED:
- new_val.lattice_val = UNDEFINED;
- new_val.value = NULL_TREE;
- break;
-
- default:
- gcc_unreachable ();
- }
+ new_val.lattice_val = UNDEFINED;
+ new_val.value = NULL_TREE;
+ new_val.mask = 0;
+ bool first = true;
for (i = 0; i < gimple_phi_num_args (phi); i++)
{
/* Compute the meet operator over all the PHI arguments flowing
tree arg = gimple_phi_arg (phi, i)->def;
ccp_prop_value_t arg_val = get_value_for_expr (arg, false);
- ccp_lattice_meet (gimple_bb (phi), &new_val, &arg_val);
+ if (first)
+ {
+ new_val = arg_val;
+ first = false;
+ }
+ else
+ ccp_lattice_meet (&new_val, &arg_val);
if (dump_file && (dump_flags & TDF_DETAILS))
{
}
/* Make the transition to the new value. */
- if (set_lattice_value (gimple_phi_result (phi), new_val))
+ if (set_lattice_value (gimple_phi_result (phi), &new_val))
{
if (new_val.lattice_val == VARYING)
return SSA_PROP_VARYING;
{
fold_defer_overflow_warnings ();
simplified = ccp_fold (stmt);
+ if (simplified && TREE_CODE (simplified) == SSA_NAME)
+ {
+ val = *get_value (simplified);
+ if (val.lattice_val != VARYING)
+ {
+ fold_undefer_overflow_warnings (true, stmt, 0);
+ return val;
+ }
+ }
is_constant = simplified && is_gimple_min_invariant (simplified);
fold_undefer_overflow_warnings (is_constant, stmt, 0);
if (is_constant)
val.lattice_val = CONSTANT;
val.value = simplified;
val.mask = 0;
+ return val;
}
}
/* If the statement is likely to have a VARYING result, then do not
return val;
}
-typedef hash_table<pointer_hash<gimple_statement_base> > gimple_htab;
+typedef hash_table<nofree_ptr_hash<gimple_statement_base> > gimple_htab;
/* Given a BUILT_IN_STACK_SAVE value SAVED_VAL, insert a clobber of VAR before
each matching BUILT_IN_STACK_RESTORE. Mark visited phis in VISITED. */
/* If STMT is an assignment to an SSA_NAME, we only have one
value to set. */
- if (set_lattice_value (lhs, val))
+ if (set_lattice_value (lhs, &val))
{
*output_p = lhs;
if (val.lattice_val == VARYING)
SSA_NAMEs represent unknown modifications to their outputs.
Mark them VARYING. */
FOR_EACH_SSA_TREE_OPERAND (def, stmt, iter, SSA_OP_ALL_DEFS)
- {
- ccp_prop_value_t v = { VARYING, NULL_TREE, -1 };
- set_lattice_value (def, v);
- }
+ set_value_varying (def);
return SSA_PROP_VARYING;
}