(convert_move): Copy SUBREG to REG in one more case.

(do_jump*): Always do comparison in object's signedness now that
combine can remove extraneous sign extends.

From-SVN: r1858
This commit is contained in:
Richard Kenner 1992-08-15 06:36:00 -04:00
parent 2fc9c644a4
commit cd1b4b4474

View File

@ -589,6 +589,12 @@ convert_move (to, from, unsignedp)
if ((code = can_extend_p (to_mode, from_mode, unsignedp))
!= CODE_FOR_nothing)
{
/* If FROM is a SUBREG, put it into a register. Do this
so that we always generate the same set of insns for
better cse'ing; if an intermediate assignment occurred,
we won't be doing the operation directly on the SUBREG. */
if (optimize > 0 && GET_CODE (from) == SUBREG)
from = force_reg (from_mode, from);
emit_unop_insn (code, to, from, equiv_code);
return;
}
@ -6198,7 +6204,8 @@ do_jump (exp, if_false_label, if_true_label)
do_jump_by_parts_equality_rtx (temp, if_true_label, if_false_label);
else if (GET_MODE (temp) != VOIDmode)
comparison = compare_from_rtx (temp, CONST0_RTX (GET_MODE (temp)),
NE, 1, GET_MODE (temp), NULL_RTX, 0);
NE, TREE_UNSIGNED (TREE_TYPE (exp)),
GET_MODE (temp), NULL_RTX, 0);
else
abort ();
}
@ -6324,7 +6331,8 @@ do_jump_by_parts_equality (exp, if_false_label, if_true_label)
{
rtx comp = compare_from_rtx (operand_subword_force (op0, i, mode),
operand_subword_force (op1, i, mode),
EQ, 0, word_mode, NULL_RTX, 0);
EQ, TREE_UNSIGNED (TREE_TYPE (exp)),
word_mode, NULL_RTX, 0);
if (comp == const_true_rtx)
emit_jump (if_false_label);
else if (comp != const0_rtx)
@ -6357,7 +6365,7 @@ do_jump_by_parts_equality_rtx (op0, if_false_label, if_true_label)
{
rtx comp = compare_from_rtx (operand_subword_force (op0, i,
GET_MODE (op0)),
const0_rtx, EQ, 0, word_mode, NULL_RTX, 0);
const0_rtx, EQ, 1, word_mode, NULL_RTX, 0);
if (comp == const_true_rtx)
emit_jump (if_false_label);
else if (comp != const0_rtx)
@ -6502,6 +6510,11 @@ compare_from_rtx (op0, op1, code, unsignedp, mode, size, align)
if (GET_CODE (op0) == CONST_INT && GET_CODE (op1) == CONST_INT)
return simplify_relational_operation (code, mode, op0, op1);
#if 0
/* There's no need to do this now that combine.c can eliminate lots of
sign extensions. This can be less efficient in certain cases on other
machines.
/* If this is a signed equality comparison, we can do it as an
unsigned comparison since zero-extension is cheaper than sign
extension and comparisons with zero are done as unsigned. This is
@ -6517,6 +6530,7 @@ compare_from_rtx (op0, op1, code, unsignedp, mode, size, align)
op1 = GEN_INT (INTVAL (op1) & GET_MODE_MASK (GET_MODE (op0)));
unsignedp = 1;
}
#endif
emit_cmp_insn (op0, op1, code, size, mode, unsignedp, align);