do_jump always does any pending stack adjust except when it does not
actually perform a jump. An example where there is no jump
- is when EXP is `(foo (), 0)' and IF_FALSE_LABEL is null.
-
- This function is responsible for optimizing cases such as
- &&, || and comparison operators in EXP. */
+ is when EXP is `(foo (), 0)' and IF_FALSE_LABEL is null. */
void
do_jump (tree exp, rtx if_false_label, rtx if_true_label)
{
enum tree_code code = TREE_CODE (exp);
- /* Some cases need to create a label to jump to
- in order to properly fall through.
- These cases set DROP_THROUGH_LABEL nonzero. */
- rtx drop_through_label = 0;
rtx temp;
int i;
tree type;
enum machine_mode mode;
- emit_queue ();
-
switch (code)
{
case ERROR_MARK:
break;
#endif
- case UNSAVE_EXPR:
- do_jump (TREE_OPERAND (exp, 0), if_false_label, if_true_label);
- TREE_OPERAND (exp, 0)
- = lang_hooks.unsave_expr_now (TREE_OPERAND (exp, 0));
- break;
-
case NOP_EXPR:
if (TREE_CODE (TREE_OPERAND (exp, 0)) == COMPONENT_REF
|| TREE_CODE (TREE_OPERAND (exp, 0)) == BIT_FIELD_REF
do_jump (TREE_OPERAND (exp, 0), if_false_label, if_true_label);
break;
-#if 0
- /* This is never less insns than evaluating the PLUS_EXPR followed by
- a test and can be longer if the test is eliminated. */
- case PLUS_EXPR:
- /* Reduce to minus. */
- exp = build (MINUS_EXPR, TREE_TYPE (exp),
- TREE_OPERAND (exp, 0),
- fold (build1 (NEGATE_EXPR, TREE_TYPE (TREE_OPERAND (exp, 1)),
- TREE_OPERAND (exp, 1))));
- /* Process as MINUS. */
-#endif
-
case MINUS_EXPR:
/* Nonzero iff operands of minus differ. */
- do_compare_and_jump (build (NE_EXPR, TREE_TYPE (exp),
- TREE_OPERAND (exp, 0),
- TREE_OPERAND (exp, 1)),
+ do_compare_and_jump (build2 (NE_EXPR, TREE_TYPE (exp),
+ TREE_OPERAND (exp, 0),
+ TREE_OPERAND (exp, 1)),
NE, NE, if_false_label, if_true_label);
break;
&& prefer_and_bit_test (TYPE_MODE (argtype),
TREE_INT_CST_LOW (shift)))
{
- do_jump (build (BIT_AND_EXPR, argtype, arg,
- fold (build (LSHIFT_EXPR, argtype, one, shift))),
+ do_jump (build2 (BIT_AND_EXPR, argtype, arg,
+ fold (build2 (LSHIFT_EXPR, argtype,
+ one, shift))),
if_false_label, if_true_label);
break;
}
break;
case TRUTH_ANDIF_EXPR:
- if (if_false_label == 0)
- if_false_label = drop_through_label = gen_label_rtx ();
- do_jump (TREE_OPERAND (exp, 0), if_false_label, NULL_RTX);
- start_cleanup_deferral ();
- do_jump (TREE_OPERAND (exp, 1), if_false_label, if_true_label);
- end_cleanup_deferral ();
- break;
-
case TRUTH_ORIF_EXPR:
- if (if_true_label == 0)
- if_true_label = drop_through_label = gen_label_rtx ();
- do_jump (TREE_OPERAND (exp, 0), NULL_RTX, if_true_label);
- start_cleanup_deferral ();
- do_jump (TREE_OPERAND (exp, 1), if_false_label, if_true_label);
- end_cleanup_deferral ();
- break;
-
case COMPOUND_EXPR:
- push_temp_slots ();
- expand_expr (TREE_OPERAND (exp, 0), const0_rtx, VOIDmode, 0);
- preserve_temp_slots (NULL_RTX);
- free_temp_slots ();
- pop_temp_slots ();
- emit_queue ();
- do_pending_stack_adjust ();
- do_jump (TREE_OPERAND (exp, 1), if_false_label, if_true_label);
- break;
+ case COND_EXPR:
+ /* Lowered by gimplify.c. */
+ abort ();
case COMPONENT_REF:
case BIT_FIELD_REF:
goto normal;
}
- case COND_EXPR:
- /* Do (a ? 1 : 0) and (a ? 0 : 1) as special cases. */
- if (integer_onep (TREE_OPERAND (exp, 1))
- && integer_zerop (TREE_OPERAND (exp, 2)))
- do_jump (TREE_OPERAND (exp, 0), if_false_label, if_true_label);
-
- else if (integer_zerop (TREE_OPERAND (exp, 1))
- && integer_onep (TREE_OPERAND (exp, 2)))
- do_jump (TREE_OPERAND (exp, 0), if_true_label, if_false_label);
-
- else
- {
- rtx label1 = gen_label_rtx ();
- drop_through_label = gen_label_rtx ();
-
- do_jump (TREE_OPERAND (exp, 0), label1, NULL_RTX);
-
- start_cleanup_deferral ();
- /* Now the THEN-expression. */
- do_jump (TREE_OPERAND (exp, 1),
- if_false_label ? if_false_label : drop_through_label,
- if_true_label ? if_true_label : drop_through_label);
- /* In case the do_jump just above never jumps. */
- do_pending_stack_adjust ();
- emit_label (label1);
-
- /* Now the ELSE-expression. */
- do_jump (TREE_OPERAND (exp, 2),
- if_false_label ? if_false_label : drop_through_label,
- if_true_label ? if_true_label : drop_through_label);
- end_cleanup_deferral ();
- }
- break;
-
case EQ_EXPR:
{
tree inner_type = TREE_TYPE (TREE_OPERAND (exp, 0));
if (GET_MODE_CLASS (TYPE_MODE (inner_type)) == MODE_COMPLEX_FLOAT
|| GET_MODE_CLASS (TYPE_MODE (inner_type)) == MODE_COMPLEX_INT)
- {
- tree exp0 = save_expr (TREE_OPERAND (exp, 0));
- tree exp1 = save_expr (TREE_OPERAND (exp, 1));
- do_jump
- (fold
- (build (TRUTH_ANDIF_EXPR, TREE_TYPE (exp),
- fold (build (EQ_EXPR, TREE_TYPE (exp),
- fold (build1 (REALPART_EXPR,
- TREE_TYPE (inner_type),
- exp0)),
- fold (build1 (REALPART_EXPR,
- TREE_TYPE (inner_type),
- exp1)))),
- fold (build (EQ_EXPR, TREE_TYPE (exp),
- fold (build1 (IMAGPART_EXPR,
- TREE_TYPE (inner_type),
- exp0)),
- fold (build1 (IMAGPART_EXPR,
- TREE_TYPE (inner_type),
- exp1)))))),
- if_false_label, if_true_label);
- }
-
+ abort ();
else if (integer_zerop (TREE_OPERAND (exp, 1)))
do_jump (TREE_OPERAND (exp, 0), if_true_label, if_false_label);
-
else if (GET_MODE_CLASS (TYPE_MODE (inner_type)) == MODE_INT
&& !can_compare_p (EQ, TYPE_MODE (inner_type), ccp_jump))
do_jump_by_parts_equality (exp, if_false_label, if_true_label);
if (GET_MODE_CLASS (TYPE_MODE (inner_type)) == MODE_COMPLEX_FLOAT
|| GET_MODE_CLASS (TYPE_MODE (inner_type)) == MODE_COMPLEX_INT)
- {
- tree exp0 = save_expr (TREE_OPERAND (exp, 0));
- tree exp1 = save_expr (TREE_OPERAND (exp, 1));
- do_jump
- (fold
- (build (TRUTH_ORIF_EXPR, TREE_TYPE (exp),
- fold (build (NE_EXPR, TREE_TYPE (exp),
- fold (build1 (REALPART_EXPR,
- TREE_TYPE (inner_type),
- exp0)),
- fold (build1 (REALPART_EXPR,
- TREE_TYPE (inner_type),
- exp1)))),
- fold (build (NE_EXPR, TREE_TYPE (exp),
- fold (build1 (IMAGPART_EXPR,
- TREE_TYPE (inner_type),
- exp0)),
- fold (build1 (IMAGPART_EXPR,
- TREE_TYPE (inner_type),
- exp1)))))),
- if_false_label, if_true_label);
- }
-
+ abort ();
else if (integer_zerop (TREE_OPERAND (exp, 1)))
do_jump (TREE_OPERAND (exp, 0), if_false_label, if_true_label);
-
else if (GET_MODE_CLASS (TYPE_MODE (inner_type)) == MODE_INT
&& !can_compare_p (NE, TYPE_MODE (inner_type), ccp_jump))
do_jump_by_parts_equality (exp, if_true_label, if_false_label);
tree op0 = save_expr (TREE_OPERAND (exp, 0));
tree op1 = save_expr (TREE_OPERAND (exp, 1));
tree cmp0, cmp1;
+ rtx drop_through_label = 0;
/* If the target doesn't support combined unordered
compares, decompose into two comparisons. */
- cmp0 = fold (build (tcode1, TREE_TYPE (exp), op0, op1));
- cmp1 = fold (build (tcode2, TREE_TYPE (exp), op0, op1));
- exp = build (TRUTH_ORIF_EXPR, TREE_TYPE (exp), cmp0, cmp1);
- do_jump (exp, if_false_label, if_true_label);
+ if (if_true_label == 0)
+ drop_through_label = if_true_label = gen_label_rtx ();
+
+ cmp0 = fold (build2 (tcode1, TREE_TYPE (exp), op0, op1));
+ cmp1 = fold (build2 (tcode2, TREE_TYPE (exp), op0, op1));
+ do_jump (cmp0, 0, if_true_label);
+ do_jump (cmp1, if_false_label, if_true_label);
+
+ if (drop_through_label)
+ {
+ do_pending_stack_adjust ();
+ emit_label (drop_through_label);
+ }
}
}
break;
default:
normal:
temp = expand_expr (exp, NULL_RTX, VOIDmode, 0);
-#if 0
- /* This is not needed any more and causes poor code since it causes
- comparisons and tests from non-SI objects to have different code
- sequences. */
- /* Copy to register to avoid generating bad insns by cse
- from (set (mem ...) (arithop)) (set (cc0) (mem ...)). */
- if (!cse_not_expected && MEM_P (temp))
- temp = copy_to_reg (temp);
-#endif
do_pending_stack_adjust ();
- /* Do any postincrements in the expression that was tested. */
- emit_queue ();
if (GET_CODE (temp) == CONST_INT
|| (GET_CODE (temp) == CONST_DOUBLE && GET_MODE (temp) == VOIDmode)
else
abort ();
}
-
- if (drop_through_label)
- {
- /* If do_jump produces code that might be jumped around,
- do any stack adjusts from that code, before the place
- where control merges in. */
- do_pending_stack_adjust ();
- emit_label (drop_through_label);
- }
}
\f
/* Given a comparison expression EXP for values too wide to be compared
}
#endif
- /* Do any postincrements in the expression that was tested. */
- emit_queue ();
-
do_compare_rtx_and_jump (op0, op1, code, unsignedp, mode,
((mode == BLKmode)
? expr_size (TREE_OPERAND (exp, 0)) : NULL_RTX),
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