#include "ggc.h"
#include "basic-block.h"
#include "output.h"
+#include "tm_p.h"
static bool prefer_and_bit_test (enum machine_mode, int);
static void do_jump_by_parts_greater (tree, tree, int, rtx, rtx, int);
static bool
prefer_and_bit_test (enum machine_mode mode, int bitnum)
{
+ bool speed_p;
+
if (and_test == 0)
{
/* Set up rtxes for the two variations. Use NULL as a placeholder
mode);
XEXP (XEXP (shift_test, 0), 1) = GEN_INT (bitnum);
- return (rtx_cost (and_test, IF_THEN_ELSE, optimize_insn_for_speed_p ())
- <= rtx_cost (shift_test, IF_THEN_ELSE, optimize_insn_for_speed_p ()));
+ speed_p = optimize_insn_for_speed_p ();
+ return (rtx_cost (and_test, IF_THEN_ELSE, 0, speed_p)
+ <= rtx_cost (shift_test, IF_THEN_ELSE, 0, speed_p));
}
/* Subroutine of do_jump, dealing with exploded comparisons of the type
{
int nwords = (GET_MODE_SIZE (mode) / UNITS_PER_WORD);
rtx drop_through_label = 0;
+ bool drop_through_if_true = false, drop_through_if_false = false;
+ enum rtx_code code = GT;
int i;
if (! if_true_label || ! if_false_label)
drop_through_label = gen_label_rtx ();
if (! if_true_label)
- if_true_label = drop_through_label;
+ {
+ if_true_label = drop_through_label;
+ drop_through_if_true = true;
+ }
if (! if_false_label)
- if_false_label = drop_through_label;
+ {
+ if_false_label = drop_through_label;
+ drop_through_if_false = true;
+ }
+
+ /* Deal with the special case 0 > x: only one comparison is necessary and
+ we reverse it to avoid jumping to the drop-through label. */
+ if (op0 == const0_rtx && drop_through_if_true && !drop_through_if_false)
+ {
+ code = LE;
+ if_true_label = if_false_label;
+ if_false_label = drop_through_label;
+ drop_through_if_true = false;
+ drop_through_if_false = true;
+ }
/* Compare a word at a time, high order first. */
for (i = 0; i < nwords; i++)
}
/* All but high-order word must be compared as unsigned. */
- do_compare_rtx_and_jump (op0_word, op1_word, GT,
- (unsignedp || i > 0), word_mode, NULL_RTX,
- NULL_RTX, if_true_label, prob);
+ do_compare_rtx_and_jump (op0_word, op1_word, code, (unsignedp || i > 0),
+ word_mode, NULL_RTX, NULL_RTX, if_true_label,
+ prob);
+
+ /* Emit only one comparison for 0. Do not emit the last cond jump. */
+ if (op0 == const0_rtx || i == nwords - 1)
+ break;
/* Consider lower words only if these are equal. */
do_compare_rtx_and_jump (op0_word, op1_word, NE, unsignedp, word_mode,
- NULL_RTX, NULL_RTX, if_false_label,
- inv (prob));
+ NULL_RTX, NULL_RTX, if_false_label, inv (prob));
}
- if (if_false_label)
+ if (!drop_through_if_false)
emit_jump (if_false_label);
if (drop_through_label)
emit_label (drop_through_label);
}
else
{
- if (GET_MODE_CLASS (mode) == MODE_FLOAT
+ if (SCALAR_FLOAT_MODE_P (mode)
&& ! can_compare_p (code, mode, ccp_jump)
&& can_compare_p (swap_condition (code), mode, ccp_jump))
{
op1 = tmp;
}
- else if (GET_MODE_CLASS (mode) == MODE_FLOAT
+ else if (SCALAR_FLOAT_MODE_P (mode)
&& ! can_compare_p (code, mode, ccp_jump)
/* Never split ORDERED and UNORDERED. These must be implemented. */