void
backprop::optimize_assign (gassign *assign, tree lhs, const usage_info *info)
{
switch (gimple_assign_rhs_code (assign))
{
case MULT_EXPR:
case RDIV_EXPR:
/* If the sign of the result doesn't matter, strip sign operations
from both inputs. */
if (info->flags.ignore_sign)
replace_assign_rhs (assign, lhs,
strip_sign_op (gimple_assign_rhs1 (assign)),
strip_sign_op (gimple_assign_rhs2 (assign)),
NULL_TREE);
break;
case COND_EXPR:
/* If the sign of A ? B : C doesn't matter, strip sign operations
from both B and C. */
if (info->flags.ignore_sign)
replace_assign_rhs (assign, lhs,
NULL_TREE,
strip_sign_op (gimple_assign_rhs2 (assign)),
strip_sign_op (gimple_assign_rhs3 (assign)));
break;
default:
break;
}
}
void
backprop::optimize_phi (gphi *phi, tree var, const usage_info *info)
{
/* If the sign of the result doesn't matter, try to strip sign operations
from arguments. */
if (info->flags.ignore_sign)
{
basic_block bb = gimple_bb (phi);
use_operand_p use;
ssa_op_iter oi;
bool replaced = false;
FOR_EACH_PHI_ARG (use, phi, oi, SSA_OP_USE)
{
/* Propagating along abnormal edges is delicate, punt for now. */
const int index = PHI_ARG_INDEX_FROM_USE (use);
if (EDGE_PRED (bb, index)->flags & EDGE_ABNORMAL)
continue;
tree new_arg = strip_sign_op (USE_FROM_PTR (use));
if (new_arg)
{
if (!replaced)
prepare_change (var);
if (dump_file && (dump_flags & TDF_DETAILS))
note_replacement (phi, USE_FROM_PTR (use), new_arg);
replace_exp (use, new_arg);
replaced = true;
}
}
}
void
backprop::optimize_builtin_call (gcall *call, tree lhs, const usage_info *info)
{
/* If we have an f such that -f(x) = f(-x), and if the sign of the result
doesn't matter, strip any sign operations from the input. */
if (info->flags.ignore_sign
&& negate_mathfn_p (gimple_call_combined_fn (call)))
{
tree new_arg = strip_sign_op (gimple_call_arg (call, 0));
if (new_arg)
{
prepare_change (lhs);
gimple_call_set_arg (call, 0, new_arg);
complete_change (call);
}
}
}
void
backprop::optimize_phi (gphi *phi, tree var, const usage_info *info)
{
/* If the sign of the result doesn't matter, strip sign operations
from all arguments. */
if (info->flags.ignore_sign)
{
use_operand_p use;
ssa_op_iter oi;
bool replaced = false;
FOR_EACH_PHI_ARG (use, phi, oi, SSA_OP_USE)
{
tree new_arg = strip_sign_op (USE_FROM_PTR (use));
if (new_arg)
{
if (!replaced)
prepare_change (var);
if (dump_file && (dump_flags & TDF_DETAILS))
note_replacement (phi, USE_FROM_PTR (use), new_arg);
replace_exp (use, new_arg);
replaced = true;
}
}