static void
tree_if_convert_cond_expr (struct loop *loop, tree stmt, tree cond,
block_stmt_iterator *bsi)
{
tree c, c2;
edge true_edge, false_edge;
gcc_assert (TREE_CODE (stmt) == COND_EXPR);
c = COND_EXPR_COND (stmt);
extract_true_false_edges_from_block (bb_for_stmt (stmt),
&true_edge, &false_edge);
/* Add new condition into destination's predicate list. */
/* If 'c' is true then TRUE_EDGE is taken. */
add_to_dst_predicate_list (loop, true_edge, cond,
unshare_expr (c), bsi);
/* If 'c' is false then FALSE_EDGE is taken. */
c2 = invert_truthvalue (unshare_expr (c));
add_to_dst_predicate_list (loop, false_edge, cond, c2, bsi);
/* Now this conditional statement is redundant. Remove it.
But, do not remove exit condition! Update exit condition
using new condition. */
if (!bb_with_exit_edge_p (loop, bb_for_stmt (stmt)))
{
bsi_remove (bsi, true);
cond = NULL_TREE;
}
return;
}
static basic_block
expand_gimple_cond_expr (basic_block bb, tree stmt)
{
basic_block new_bb, dest;
edge new_edge;
edge true_edge;
edge false_edge;
tree pred = COND_EXPR_COND (stmt);
tree then_exp = COND_EXPR_THEN (stmt);
tree else_exp = COND_EXPR_ELSE (stmt);
rtx last2, last;
last2 = last = get_last_insn ();
extract_true_false_edges_from_block (bb, &true_edge, &false_edge);
if (EXPR_LOCUS (stmt))
{
emit_line_note (*(EXPR_LOCUS (stmt)));
record_block_change (TREE_BLOCK (stmt));
}
/* These flags have no purpose in RTL land. */
true_edge->flags &= ~EDGE_TRUE_VALUE;
false_edge->flags &= ~EDGE_FALSE_VALUE;
/* We can either have a pure conditional jump with one fallthru edge or
two-way jump that needs to be decomposed into two basic blocks. */
if (TREE_CODE (then_exp) == GOTO_EXPR && IS_EMPTY_STMT (else_exp))
{
jumpif (pred, label_rtx (GOTO_DESTINATION (then_exp)));
add_reg_br_prob_note (dump_file, last, true_edge->probability);
maybe_dump_rtl_for_tree_stmt (stmt, last);
if (EXPR_LOCUS (then_exp))
emit_line_note (*(EXPR_LOCUS (then_exp)));
return NULL;
}
if (TREE_CODE (else_exp) == GOTO_EXPR && IS_EMPTY_STMT (then_exp))
{
jumpifnot (pred, label_rtx (GOTO_DESTINATION (else_exp)));
add_reg_br_prob_note (dump_file, last, false_edge->probability);
maybe_dump_rtl_for_tree_stmt (stmt, last);
if (EXPR_LOCUS (else_exp))
emit_line_note (*(EXPR_LOCUS (else_exp)));
return NULL;
}
gcc_assert (TREE_CODE (then_exp) == GOTO_EXPR
&& TREE_CODE (else_exp) == GOTO_EXPR);
jumpif (pred, label_rtx (GOTO_DESTINATION (then_exp)));
add_reg_br_prob_note (dump_file, last, true_edge->probability);
last = get_last_insn ();
expand_expr (else_exp, const0_rtx, VOIDmode, 0);
BB_END (bb) = last;
if (BARRIER_P (BB_END (bb)))
BB_END (bb) = PREV_INSN (BB_END (bb));
update_bb_for_insn (bb);
new_bb = create_basic_block (NEXT_INSN (last), get_last_insn (), bb);
dest = false_edge->dest;
redirect_edge_succ (false_edge, new_bb);
false_edge->flags |= EDGE_FALLTHRU;
new_bb->count = false_edge->count;
new_bb->frequency = EDGE_FREQUENCY (false_edge);
new_edge = make_edge (new_bb, dest, 0);
new_edge->probability = REG_BR_PROB_BASE;
new_edge->count = new_bb->count;
if (BARRIER_P (BB_END (new_bb)))
BB_END (new_bb) = PREV_INSN (BB_END (new_bb));
update_bb_for_insn (new_bb);
maybe_dump_rtl_for_tree_stmt (stmt, last2);
if (EXPR_LOCUS (else_exp))
emit_line_note (*(EXPR_LOCUS (else_exp)));
return new_bb;
}
static bool
abs_replacement (basic_block cond_bb, basic_block middle_bb,
edge e0 ATTRIBUTE_UNUSED, edge e1,
gimple phi, tree arg0, tree arg1)
{
tree result;
gimple new_stmt, cond;
gimple_stmt_iterator gsi;
edge true_edge, false_edge;
gimple assign;
edge e;
tree rhs, lhs;
bool negate;
enum tree_code cond_code;
/* If the type says honor signed zeros we cannot do this
optimization. */
if (HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg1))))
return false;
/* OTHER_BLOCK must have only one executable statement which must have the
form arg0 = -arg1 or arg1 = -arg0. */
assign = last_and_only_stmt (middle_bb);
/* If we did not find the proper negation assignment, then we can not
optimize. */
if (assign == NULL)
return false;
/* If we got here, then we have found the only executable statement
in OTHER_BLOCK. If it is anything other than arg = -arg1 or
arg1 = -arg0, then we can not optimize. */
if (gimple_code (assign) != GIMPLE_ASSIGN)
return false;
lhs = gimple_assign_lhs (assign);
if (gimple_assign_rhs_code (assign) != NEGATE_EXPR)
return false;
rhs = gimple_assign_rhs1 (assign);
/* The assignment has to be arg0 = -arg1 or arg1 = -arg0. */
if (!(lhs == arg0 && rhs == arg1)
&& !(lhs == arg1 && rhs == arg0))
return false;
cond = last_stmt (cond_bb);
result = PHI_RESULT (phi);
/* Only relationals comparing arg[01] against zero are interesting. */
cond_code = gimple_cond_code (cond);
if (cond_code != GT_EXPR && cond_code != GE_EXPR
&& cond_code != LT_EXPR && cond_code != LE_EXPR)
return false;
/* Make sure the conditional is arg[01] OP y. */
if (gimple_cond_lhs (cond) != rhs)
return false;
if (FLOAT_TYPE_P (TREE_TYPE (gimple_cond_rhs (cond)))
? real_zerop (gimple_cond_rhs (cond))
: integer_zerop (gimple_cond_rhs (cond)))
;
else
return false;
/* We need to know which is the true edge and which is the false
edge so that we know if have abs or negative abs. */
extract_true_false_edges_from_block (cond_bb, &true_edge, &false_edge);
/* For GT_EXPR/GE_EXPR, if the true edge goes to OTHER_BLOCK, then we
will need to negate the result. Similarly for LT_EXPR/LE_EXPR if
the false edge goes to OTHER_BLOCK. */
if (cond_code == GT_EXPR || cond_code == GE_EXPR)
e = true_edge;
else
e = false_edge;
if (e->dest == middle_bb)
negate = true;
else
negate = false;
result = duplicate_ssa_name (result, NULL);
if (negate)
{
tree tmp = create_tmp_var (TREE_TYPE (result), NULL);
add_referenced_var (tmp);
lhs = make_ssa_name (tmp, NULL);
}
else
lhs = result;
/* Build the modify expression with abs expression. */
new_stmt = gimple_build_assign_with_ops (ABS_EXPR, lhs, rhs, NULL);
gsi = gsi_last_bb (cond_bb);
gsi_insert_before (&gsi, new_stmt, GSI_NEW_STMT);
if (negate)
{
/* Get the right GSI. We want to insert after the recently
added ABS_EXPR statement (which we know is the first statement
in the block. */
new_stmt = gimple_build_assign_with_ops (NEGATE_EXPR, result, lhs, NULL);
gsi_insert_after (&gsi, new_stmt, GSI_NEW_STMT);
}
replace_phi_edge_with_variable (cond_bb, e1, phi, result);
/* Note that we optimized this PHI. */
return true;
}
static bool
minmax_replacement (basic_block cond_bb, basic_block middle_bb,
edge e0, edge e1, gimple phi,
tree arg0, tree arg1)
{
tree result, type;
gimple cond, new_stmt;
edge true_edge, false_edge;
enum tree_code cmp, minmax, ass_code;
tree smaller, larger, arg_true, arg_false;
gimple_stmt_iterator gsi, gsi_from;
type = TREE_TYPE (PHI_RESULT (phi));
/* The optimization may be unsafe due to NaNs. */
if (HONOR_NANS (TYPE_MODE (type)))
return false;
cond = last_stmt (cond_bb);
cmp = gimple_cond_code (cond);
result = PHI_RESULT (phi);
/* This transformation is only valid for order comparisons. Record which
operand is smaller/larger if the result of the comparison is true. */
if (cmp == LT_EXPR || cmp == LE_EXPR)
{
smaller = gimple_cond_lhs (cond);
larger = gimple_cond_rhs (cond);
}
else if (cmp == GT_EXPR || cmp == GE_EXPR)
{
smaller = gimple_cond_rhs (cond);
larger = gimple_cond_lhs (cond);
}
else
return false;
/* We need to know which is the true edge and which is the false
edge so that we know if have abs or negative abs. */
extract_true_false_edges_from_block (cond_bb, &true_edge, &false_edge);
/* Forward the edges over the middle basic block. */
if (true_edge->dest == middle_bb)
true_edge = EDGE_SUCC (true_edge->dest, 0);
if (false_edge->dest == middle_bb)
false_edge = EDGE_SUCC (false_edge->dest, 0);
if (true_edge == e0)
{
gcc_assert (false_edge == e1);
arg_true = arg0;
arg_false = arg1;
}
else
{
gcc_assert (false_edge == e0);
gcc_assert (true_edge == e1);
arg_true = arg1;
arg_false = arg0;
}
if (empty_block_p (middle_bb))
{
if (operand_equal_for_phi_arg_p (arg_true, smaller)
&& operand_equal_for_phi_arg_p (arg_false, larger))
{
/* Case
if (smaller < larger)
rslt = smaller;
else
rslt = larger; */
minmax = MIN_EXPR;
}
else if (operand_equal_for_phi_arg_p (arg_false, smaller)
&& operand_equal_for_phi_arg_p (arg_true, larger))
minmax = MAX_EXPR;
else
return false;
}
else
{
/* Recognize the following case, assuming d <= u:
if (a <= u)
b = MAX (a, d);
x = PHI <b, u>
This is equivalent to
b = MAX (a, d);
x = MIN (b, u); */
gimple assign = last_and_only_stmt (middle_bb);
tree lhs, op0, op1, bound;
if (!assign
|| gimple_code (assign) != GIMPLE_ASSIGN)
return false;
lhs = gimple_assign_lhs (assign);
ass_code = gimple_assign_rhs_code (assign);
if (ass_code != MAX_EXPR && ass_code != MIN_EXPR)
return false;
op0 = gimple_assign_rhs1 (assign);
op1 = gimple_assign_rhs2 (assign);
if (true_edge->src == middle_bb)
{
/* We got here if the condition is true, i.e., SMALLER < LARGER. */
if (!operand_equal_for_phi_arg_p (lhs, arg_true))
return false;
if (operand_equal_for_phi_arg_p (arg_false, larger))
{
/* Case
if (smaller < larger)
{
r' = MAX_EXPR (smaller, bound)
}
r = PHI <r', larger> --> to be turned to MIN_EXPR. */
if (ass_code != MAX_EXPR)
return false;
minmax = MIN_EXPR;
if (operand_equal_for_phi_arg_p (op0, smaller))
bound = op1;
else if (operand_equal_for_phi_arg_p (op1, smaller))
bound = op0;
else
return false;
/* We need BOUND <= LARGER. */
if (!integer_nonzerop (fold_build2 (LE_EXPR, boolean_type_node,
bound, larger)))
return false;
}
else if (operand_equal_for_phi_arg_p (arg_false, smaller))
{
/* Case
if (smaller < larger)
{
r' = MIN_EXPR (larger, bound)
}
r = PHI <r', smaller> --> to be turned to MAX_EXPR. */
if (ass_code != MIN_EXPR)
return false;
minmax = MAX_EXPR;
if (operand_equal_for_phi_arg_p (op0, larger))
bound = op1;
else if (operand_equal_for_phi_arg_p (op1, larger))
bound = op0;
else
return false;
/* We need BOUND >= SMALLER. */
if (!integer_nonzerop (fold_build2 (GE_EXPR, boolean_type_node,
bound, smaller)))
return false;
}
else
return false;
}
else
{
/* We got here if the condition is false, i.e., SMALLER > LARGER. */
if (!operand_equal_for_phi_arg_p (lhs, arg_false))
return false;
if (operand_equal_for_phi_arg_p (arg_true, larger))
{
/* Case
if (smaller > larger)
{
r' = MIN_EXPR (smaller, bound)
}
r = PHI <r', larger> --> to be turned to MAX_EXPR. */
if (ass_code != MIN_EXPR)
return false;
minmax = MAX_EXPR;
if (operand_equal_for_phi_arg_p (op0, smaller))
bound = op1;
else if (operand_equal_for_phi_arg_p (op1, smaller))
bound = op0;
else
return false;
/* We need BOUND >= LARGER. */
if (!integer_nonzerop (fold_build2 (GE_EXPR, boolean_type_node,
bound, larger)))
return false;
}
else if (operand_equal_for_phi_arg_p (arg_true, smaller))
{
/* Case
if (smaller > larger)
{
r' = MAX_EXPR (larger, bound)
}
r = PHI <r', smaller> --> to be turned to MIN_EXPR. */
if (ass_code != MAX_EXPR)
return false;
minmax = MIN_EXPR;
if (operand_equal_for_phi_arg_p (op0, larger))
bound = op1;
else if (operand_equal_for_phi_arg_p (op1, larger))
bound = op0;
else
return false;
/* We need BOUND <= SMALLER. */
if (!integer_nonzerop (fold_build2 (LE_EXPR, boolean_type_node,
bound, smaller)))
return false;
}
else
return false;
}
/* Move the statement from the middle block. */
gsi = gsi_last_bb (cond_bb);
gsi_from = gsi_last_bb (middle_bb);
gsi_move_before (&gsi_from, &gsi);
}
/* Emit the statement to compute min/max. */
result = duplicate_ssa_name (PHI_RESULT (phi), NULL);
new_stmt = gimple_build_assign_with_ops (minmax, result, arg0, arg1);
gsi = gsi_last_bb (cond_bb);
gsi_insert_before (&gsi, new_stmt, GSI_NEW_STMT);
replace_phi_edge_with_variable (cond_bb, e1, phi, result);
return true;
}
static bool
value_replacement (basic_block cond_bb, basic_block middle_bb,
edge e0, edge e1, gimple phi,
tree arg0, tree arg1)
{
gimple cond;
edge true_edge, false_edge;
enum tree_code code;
/* If the type says honor signed zeros we cannot do this
optimization. */
if (HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg1))))
return false;
if (!empty_block_p (middle_bb))
return false;
cond = last_stmt (cond_bb);
code = gimple_cond_code (cond);
/* This transformation is only valid for equality comparisons. */
if (code != NE_EXPR && code != EQ_EXPR)
return false;
/* We need to know which is the true edge and which is the false
edge so that we know if have abs or negative abs. */
extract_true_false_edges_from_block (cond_bb, &true_edge, &false_edge);
/* At this point we know we have a COND_EXPR with two successors.
One successor is BB, the other successor is an empty block which
falls through into BB.
The condition for the COND_EXPR is known to be NE_EXPR or EQ_EXPR.
There is a single PHI node at the join point (BB) with two arguments.
We now need to verify that the two arguments in the PHI node match
the two arguments to the equality comparison. */
if ((operand_equal_for_phi_arg_p (arg0, gimple_cond_lhs (cond))
&& operand_equal_for_phi_arg_p (arg1, gimple_cond_rhs (cond)))
|| (operand_equal_for_phi_arg_p (arg1, gimple_cond_lhs (cond))
&& operand_equal_for_phi_arg_p (arg0, gimple_cond_rhs (cond))))
{
edge e;
tree arg;
/* For NE_EXPR, we want to build an assignment result = arg where
arg is the PHI argument associated with the true edge. For
EQ_EXPR we want the PHI argument associated with the false edge. */
e = (code == NE_EXPR ? true_edge : false_edge);
/* Unfortunately, E may not reach BB (it may instead have gone to
OTHER_BLOCK). If that is the case, then we want the single outgoing
edge from OTHER_BLOCK which reaches BB and represents the desired
path from COND_BLOCK. */
if (e->dest == middle_bb)
e = single_succ_edge (e->dest);
/* Now we know the incoming edge to BB that has the argument for the
RHS of our new assignment statement. */
if (e0 == e)
arg = arg0;
else
arg = arg1;
replace_phi_edge_with_variable (cond_bb, e1, phi, arg);
/* Note that we optimized this PHI. */
return true;
}
return false;
}
static bool
conditional_replacement (basic_block cond_bb, basic_block middle_bb,
edge e0, edge e1, gimple phi,
tree arg0, tree arg1)
{
tree result;
gimple stmt, new_stmt;
tree cond;
gimple_stmt_iterator gsi;
edge true_edge, false_edge;
tree new_var, new_var2;
/* FIXME: Gimplification of complex type is too hard for now. */
if (TREE_CODE (TREE_TYPE (arg0)) == COMPLEX_TYPE
|| TREE_CODE (TREE_TYPE (arg1)) == COMPLEX_TYPE)
return false;
/* The PHI arguments have the constants 0 and 1, then convert
it to the conditional. */
if ((integer_zerop (arg0) && integer_onep (arg1))
|| (integer_zerop (arg1) && integer_onep (arg0)))
;
else
return false;
if (!empty_block_p (middle_bb))
return false;
/* At this point we know we have a GIMPLE_COND with two successors.
One successor is BB, the other successor is an empty block which
falls through into BB.
There is a single PHI node at the join point (BB) and its arguments
are constants (0, 1).
So, given the condition COND, and the two PHI arguments, we can
rewrite this PHI into non-branching code:
dest = (COND) or dest = COND'
We use the condition as-is if the argument associated with the
true edge has the value one or the argument associated with the
false edge as the value zero. Note that those conditions are not
the same since only one of the outgoing edges from the GIMPLE_COND
will directly reach BB and thus be associated with an argument. */
stmt = last_stmt (cond_bb);
result = PHI_RESULT (phi);
/* To handle special cases like floating point comparison, it is easier and
less error-prone to build a tree and gimplify it on the fly though it is
less efficient. */
cond = fold_build2 (gimple_cond_code (stmt), boolean_type_node,
gimple_cond_lhs (stmt), gimple_cond_rhs (stmt));
/* We need to know which is the true edge and which is the false
edge so that we know when to invert the condition below. */
extract_true_false_edges_from_block (cond_bb, &true_edge, &false_edge);
if ((e0 == true_edge && integer_zerop (arg0))
|| (e0 == false_edge && integer_onep (arg0))
|| (e1 == true_edge && integer_zerop (arg1))
|| (e1 == false_edge && integer_onep (arg1)))
cond = fold_build1 (TRUTH_NOT_EXPR, TREE_TYPE (cond), cond);
/* Insert our new statements at the end of conditional block before the
COND_STMT. */
gsi = gsi_for_stmt (stmt);
new_var = force_gimple_operand_gsi (&gsi, cond, true, NULL, true,
GSI_SAME_STMT);
if (!useless_type_conversion_p (TREE_TYPE (result), TREE_TYPE (new_var)))
{
new_var2 = create_tmp_var (TREE_TYPE (result), NULL);
add_referenced_var (new_var2);
new_stmt = gimple_build_assign_with_ops (CONVERT_EXPR, new_var2,
new_var, NULL);
new_var2 = make_ssa_name (new_var2, new_stmt);
gimple_assign_set_lhs (new_stmt, new_var2);
gsi_insert_before (&gsi, new_stmt, GSI_SAME_STMT);
new_var = new_var2;
}
replace_phi_edge_with_variable (cond_bb, e1, phi, new_var);
/* Note that we optimized this PHI. */
return true;
}