if (start < finish)
{
inner = GET_MODE (tmps[start]);
- bytepos = subreg_lowpart_offset (outer, inner);
+ bytepos = subreg_lowpart_offset (inner, outer);
if (INTVAL (XEXP (XVECEXP (src, 0, start), 1)) == bytepos)
{
temp = simplify_gen_subreg (outer, tmps[start],
- inner, bytepos);
+ inner, 0);
if (temp)
{
emit_move_insn (dst, temp);
&& start < finish - 1)
{
inner = GET_MODE (tmps[finish - 1]);
- bytepos = subreg_lowpart_offset (outer, inner);
+ bytepos = subreg_lowpart_offset (inner, outer);
if (INTVAL (XEXP (XVECEXP (src, 0, finish - 1), 1)) == bytepos)
{
temp = simplify_gen_subreg (outer, tmps[finish - 1],
- inner, bytepos);
+ inner, 0);
if (temp)
{
emit_move_insn (dst, temp);
return ret;
}
+/* Return true if word I of OP lies entirely in the
+ undefined bits of a paradoxical subreg. */
+
+static bool
+undefined_operand_subword_p (rtx op, int i)
+{
+ enum machine_mode innermode, innermostmode;
+ int offset;
+ if (GET_CODE (op) != SUBREG)
+ return false;
+ innermode = GET_MODE (op);
+ innermostmode = GET_MODE (SUBREG_REG (op));
+ offset = i * UNITS_PER_WORD + SUBREG_BYTE (op);
+ /* The SUBREG_BYTE represents offset, as if the value were stored in
+ memory, except for a paradoxical subreg where we define
+ SUBREG_BYTE to be 0; undo this exception as in
+ simplify_subreg. */
+ if (SUBREG_BYTE (op) == 0
+ && GET_MODE_SIZE (innermostmode) < GET_MODE_SIZE (innermode))
+ {
+ int difference = (GET_MODE_SIZE (innermostmode) - GET_MODE_SIZE (innermode));
+ if (WORDS_BIG_ENDIAN)
+ offset += (difference / UNITS_PER_WORD) * UNITS_PER_WORD;
+ if (BYTES_BIG_ENDIAN)
+ offset += difference % UNITS_PER_WORD;
+ }
+ if (offset >= GET_MODE_SIZE (innermostmode)
+ || offset <= -GET_MODE_SIZE (word_mode))
+ return true;
+ return false;
+}
+
/* A subroutine of emit_move_insn_1. Generate a move from Y into X.
MODE is any multi-word or full-word mode that lacks a move_insn
pattern. Note that you will get better code if you define such
i++)
{
rtx xpart = operand_subword (x, i, 1, mode);
- rtx ypart = operand_subword (y, i, 1, mode);
+ rtx ypart;
+
+ /* Do not generate code for a move if it would come entirely
+ from the undefined bits of a paradoxical subreg. */
+ if (undefined_operand_subword_p (y, i))
+ continue;
+
+ ypart = operand_subword (y, i, 1, mode);
/* If we can't get a part of Y, put Y into memory if it is a
constant. Otherwise, force it into a register. Then we must
}
else
continue;
-
+
+ /* For CSE's benefit, force the compressed constant pool entry
+ into a new pseudo. This constant may be used in different modes,
+ and if not, combine will put things back together for us. */
+ trunc_y = force_reg (srcmode, trunc_y);
emit_unop_insn (ic, x, trunc_y, UNKNOWN);
last_insn = get_last_insn ();
rtx result;
/* Don't crash if the lhs of the assignment was erroneous. */
-
if (TREE_CODE (to) == ERROR_MARK)
{
result = expand_normal (from);
return;
}
+ /* Optimize away no-op moves without side-effects. */
+ if (operand_equal_p (to, from, 0))
+ return;
+
/* Assignment of a structure component needs special treatment
if the structure component's rtx is not simply a MEM.
Assignment of an array element at a constant index, and assignment of
}
/* Inform later passes that the old value is dead. */
- if (!cleared && REG_P (target))
+ if (!cleared && !vector && REG_P (target))
emit_move_insn (target, CONST0_RTX (GET_MODE (target)));
/* Store each element of the constructor into the corresponding
return safe_from_p (x, exp, 0);
}
}
+ else if (TREE_CODE (exp) == CONSTRUCTOR)
+ {
+ constructor_elt *ce;
+ unsigned HOST_WIDE_INT idx;
+
+ for (idx = 0;
+ VEC_iterate (constructor_elt, CONSTRUCTOR_ELTS (exp), idx, ce);
+ idx++)
+ if ((ce->index != NULL_TREE && !safe_from_p (x, ce->index, 0))
+ || !safe_from_p (x, ce->value, 0))
+ return 0;
+ return 1;
+ }
else if (TREE_CODE (exp) == ERROR_MARK)
return 1; /* An already-visited SAVE_EXPR? */
else
return temp;
case VECTOR_CST:
- if (GET_MODE_CLASS (TYPE_MODE (TREE_TYPE (exp))) == MODE_VECTOR_INT
- || GET_MODE_CLASS (TYPE_MODE (TREE_TYPE (exp))) == MODE_VECTOR_FLOAT)
- return const_vector_from_tree (exp);
- else
- return expand_expr (build_constructor_from_list
- (TREE_TYPE (exp),
- TREE_VECTOR_CST_ELTS (exp)),
- ignore ? const0_rtx : target, tmode, modifier);
+ {
+ tree tmp = NULL_TREE;
+ if (GET_MODE_CLASS (mode) == MODE_VECTOR_INT
+ || GET_MODE_CLASS (mode) == MODE_VECTOR_FLOAT)
+ return const_vector_from_tree (exp);
+ if (GET_MODE_CLASS (mode) == MODE_INT)
+ {
+ tree type_for_mode = lang_hooks.types.type_for_mode (mode, 1);
+ if (type_for_mode)
+ tmp = fold_unary (VIEW_CONVERT_EXPR, type_for_mode, exp);
+ }
+ if (!tmp)
+ tmp = build_constructor_from_list (type,
+ TREE_VECTOR_CST_ELTS (exp));
+ return expand_expr (tmp, ignore ? const0_rtx : target,
+ tmode, modifier);
+ }
case CONST_DECL:
return expand_expr (DECL_INITIAL (exp), target, VOIDmode, modifier);
else if (!MEM_P (op0))
{
/* If the operand is not a MEM, force it into memory. Since we
- are going to be be changing the mode of the MEM, don't call
+ are going to be changing the mode of the MEM, don't call
force_const_mem for constants because we don't allow pool
constants to change mode. */
tree inner_type = TREE_TYPE (TREE_OPERAND (exp, 0));
OSDN Git Service
