}
/* Split a post-reload TImode or TFmode reference into two DImode
- components. */
+ components. This is made extra difficult by the fact that we do
+ not get any scratch registers to work with, because reload cannot
+ be prevented from giving us a scratch that overlaps the register
+ pair involved. So instead, when addressing memory, we tweak the
+ pointer register up and back down with POST_INCs. Or up and not
+ back down when we can get away with it.
+
+ REVERSED is true when the loads must be done in reversed order
+ (high word first) for correctness. DEAD is true when the pointer
+ dies with the second insn we generate and therefore the second
+ address must not carry a postmodify.
+
+ May return an insn which is to be emitted after the moves. */
static rtx
-ia64_split_tmode (rtx out[2], rtx in, rtx scratch)
+ia64_split_tmode (rtx out[2], rtx in, bool reversed, bool dead)
{
+ rtx fixup = 0;
+
switch (GET_CODE (in))
{
case REG:
- out[0] = gen_rtx_REG (DImode, REGNO (in));
- out[1] = gen_rtx_REG (DImode, REGNO (in) + 1);
- return NULL_RTX;
-
- case MEM:
- {
- rtx base = XEXP (in, 0);
-
- switch (GET_CODE (base))
- {
- case REG:
- out[0] = adjust_address (in, DImode, 0);
- break;
- case POST_MODIFY:
- base = XEXP (base, 0);
- out[0] = adjust_address (in, DImode, 0);
- break;
-
- /* Since we're changing the mode, we need to change to POST_MODIFY
- as well to preserve the size of the increment. Either that or
- do the update in two steps, but we've already got this scratch
- register handy so let's use it. */
- case POST_INC:
- base = XEXP (base, 0);
- out[0]
- = change_address (in, DImode,
- gen_rtx_POST_MODIFY
- (Pmode, base, plus_constant (base, 16)));
- break;
- case POST_DEC:
- base = XEXP (base, 0);
- out[0]
- = change_address (in, DImode,
- gen_rtx_POST_MODIFY
- (Pmode, base, plus_constant (base, -16)));
- break;
- default:
- abort ();
- }
-
- if (scratch == NULL_RTX)
- abort ();
- out[1] = change_address (in, DImode, scratch);
- return gen_adddi3 (scratch, base, GEN_INT (8));
- }
+ out[reversed] = gen_rtx_REG (DImode, REGNO (in));
+ out[!reversed] = gen_rtx_REG (DImode, REGNO (in) + 1);
+ break;
case CONST_INT:
case CONST_DOUBLE:
+ /* Cannot occur reversed. */
+ if (reversed) abort ();
+
if (GET_MODE (in) != TFmode)
split_double (in, &out[0], &out[1]);
else
out[0] = GEN_INT (p[0]);
out[1] = GEN_INT (p[1]);
}
- return NULL_RTX;
+ break;
+
+ case MEM:
+ {
+ rtx base = XEXP (in, 0);
+ rtx offset;
+
+ switch (GET_CODE (base))
+ {
+ case REG:
+ if (!reversed)
+ {
+ out[0] = adjust_automodify_address
+ (in, DImode, gen_rtx_POST_INC (Pmode, base), 0);
+ out[1] = adjust_automodify_address
+ (in, DImode, dead ? 0 : gen_rtx_POST_DEC (Pmode, base), 8);
+ }
+ else
+ {
+ /* Reversal requires a pre-increment, which can only
+ be done as a separate insn. */
+ emit_insn (gen_adddi3 (base, base, GEN_INT (8)));
+ out[0] = adjust_automodify_address
+ (in, DImode, gen_rtx_POST_DEC (Pmode, base), 8);
+ out[1] = adjust_address (in, DImode, 0);
+ }
+ break;
+
+ case POST_INC:
+ if (reversed || dead) abort ();
+ /* Just do the increment in two steps. */
+ out[0] = adjust_automodify_address (in, DImode, 0, 0);
+ out[1] = adjust_automodify_address (in, DImode, 0, 8);
+ break;
+
+ case POST_DEC:
+ if (reversed || dead) abort ();
+ /* Add 8, subtract 24. */
+ base = XEXP (base, 0);
+ out[0] = adjust_automodify_address
+ (in, DImode, gen_rtx_POST_INC (Pmode, base), 0);
+ out[1] = adjust_automodify_address
+ (in, DImode,
+ gen_rtx_POST_MODIFY (Pmode, base, plus_constant (base, -24)),
+ 8);
+ break;
+
+ case POST_MODIFY:
+ if (reversed || dead) abort ();
+ /* Extract and adjust the modification. This case is
+ trickier than the others, because we might have an
+ index register, or we might have a combined offset that
+ doesn't fit a signed 9-bit displacement field. We can
+ assume the incoming expression is already legitimate. */
+ offset = XEXP (base, 1);
+ base = XEXP (base, 0);
+
+ out[0] = adjust_automodify_address
+ (in, DImode, gen_rtx_POST_INC (Pmode, base), 0);
+
+ if (GET_CODE (XEXP (offset, 1)) == REG)
+ {
+ /* Can't adjust the postmodify to match. Emit the
+ original, then a separate addition insn. */
+ out[1] = adjust_automodify_address (in, DImode, 0, 8);
+ fixup = gen_adddi3 (base, base, GEN_INT (-8));
+ }
+ else if (GET_CODE (XEXP (offset, 1)) != CONST_INT)
+ abort ();
+ else if (INTVAL (XEXP (offset, 1)) < -256 + 8)
+ {
+ /* Again the postmodify cannot be made to match, but
+ in this case it's more efficient to get rid of the
+ postmodify entirely and fix up with an add insn. */
+ out[1] = adjust_automodify_address (in, DImode, base, 8);
+ fixup = gen_adddi3 (base, base,
+ GEN_INT (INTVAL (XEXP (offset, 1)) - 8));
+ }
+ else
+ {
+ /* Combined offset still fits in the displacement field.
+ (We cannot overflow it at the high end.) */
+ out[1] = adjust_automodify_address
+ (in, DImode,
+ gen_rtx_POST_MODIFY (Pmode, base,
+ gen_rtx_PLUS (Pmode, base,
+ GEN_INT (INTVAL (XEXP (offset, 1)) - 8))),
+ 8);
+ }
+ break;
+
+ default:
+ abort ();
+ }
+ break;
+ }
default:
abort ();
}
+
+ return fixup;
}
/* Split a TImode or TFmode move instruction after reload.
void
ia64_split_tmode_move (rtx operands[])
{
- rtx adj1, adj2, in[2], out[2], insn;
- int first;
-
- adj1 = ia64_split_tmode (in, operands[1], operands[2]);
- adj2 = ia64_split_tmode (out, operands[0], operands[2]);
-
- first = 0;
- if (reg_overlap_mentioned_p (out[0], in[1]))
- {
- if (reg_overlap_mentioned_p (out[1], in[0]))
- abort ();
- first = 1;
- }
-
- if (adj1 && adj2)
- abort ();
- if (adj1)
- emit_insn (adj1);
- if (adj2)
- emit_insn (adj2);
- insn = emit_insn (gen_rtx_SET (VOIDmode, out[first], in[first]));
- if (GET_CODE (out[first]) == MEM
- && GET_CODE (XEXP (out[first], 0)) == POST_MODIFY)
- REG_NOTES (insn) = gen_rtx_EXPR_LIST (REG_INC,
- XEXP (XEXP (out[first], 0), 0),
- REG_NOTES (insn));
- insn = emit_insn (gen_rtx_SET (VOIDmode, out[!first], in[!first]));
- if (GET_CODE (out[!first]) == MEM
- && GET_CODE (XEXP (out[!first], 0)) == POST_MODIFY)
- REG_NOTES (insn) = gen_rtx_EXPR_LIST (REG_INC,
- XEXP (XEXP (out[!first], 0), 0),
- REG_NOTES (insn));
-
+ rtx in[2], out[2], insn;
+ rtx fixup[2];
+ bool dead = false;
+ bool reversed = false;
+
+ /* It is possible for reload to decide to overwrite a pointer with
+ the value it points to. In that case we have to do the loads in
+ the appropriate order so that the pointer is not destroyed too
+ early. Also we must not generate a postmodify for that second
+ load, or rws_access_regno will abort. */
+ if (GET_CODE (operands[1]) == MEM
+ && reg_overlap_mentioned_p (operands[0], operands[1]))
+ {
+ rtx base = XEXP (operands[1], 0);
+ while (GET_CODE (base) != REG)
+ base = XEXP (base, 0);
+
+ if (REGNO (base) == REGNO (operands[0]))
+ reversed = true;
+ dead = true;
+ }
+ /* Another reason to do the moves in reversed order is if the first
+ element of the target register pair is also the second element of
+ the source register pair. */
+ if (GET_CODE (operands[0]) == REG && GET_CODE (operands[1]) == REG
+ && REGNO (operands[0]) == REGNO (operands[1]) + 1)
+ reversed = true;
+
+ fixup[0] = ia64_split_tmode (in, operands[1], reversed, dead);
+ fixup[1] = ia64_split_tmode (out, operands[0], reversed, dead);
+
+#define MAYBE_ADD_REG_INC_NOTE(INSN, EXP) \
+ if (GET_CODE (EXP) == MEM \
+ && (GET_CODE (XEXP (EXP, 0)) == POST_MODIFY \
+ || GET_CODE (XEXP (EXP, 0)) == POST_INC \
+ || GET_CODE (XEXP (EXP, 0)) == POST_DEC)) \
+ REG_NOTES (INSN) = gen_rtx_EXPR_LIST (REG_INC, \
+ XEXP (XEXP (EXP, 0), 0), \
+ REG_NOTES (INSN))
+
+ insn = emit_insn (gen_rtx_SET (VOIDmode, out[0], in[0]));
+ MAYBE_ADD_REG_INC_NOTE (insn, in[0]);
+ MAYBE_ADD_REG_INC_NOTE (insn, out[0]);
+
+ insn = emit_insn (gen_rtx_SET (VOIDmode, out[1], in[1]));
+ MAYBE_ADD_REG_INC_NOTE (insn, in[1]);
+ MAYBE_ADD_REG_INC_NOTE (insn, out[1]);
+
+ if (fixup[0])
+ emit_insn (fixup[0]);
+ if (fixup[1])
+ emit_insn (fixup[1]);
+
+#undef MAYBE_ADD_REG_INC_NOTE
}
/* ??? Fixing GR->FR XFmode moves during reload is hard. You need to go
return GR_REGS;
break;
- case GR_REGS:
- /* Since we have no offsettable memory addresses, we need a temporary
- to hold the address of the second word. */
- if (mode == TImode || mode == TFmode)
- return GR_REGS;
- break;
-
default:
break;
}
[(set_attr "itanium_class" "ialu")])
;; With no offsettable memory references, we've got to have a scratch
-;; around to play with the second word.
+;; around to play with the second word. However, in order to avoid a
+;; reload nightmare we lie, claim we don't need one, and fix it up
+;; in ia64_split_tmode_move.
(define_expand "movti"
- [(parallel [(set (match_operand:TI 0 "general_operand" "")
- (match_operand:TI 1 "general_operand" ""))
- (clobber (match_scratch:DI 2 ""))])]
+ [(set (match_operand:TI 0 "general_operand" "")
+ (match_operand:TI 1 "general_operand" ""))]
""
{
rtx op1 = ia64_expand_move (operands[0], operands[1]);
(define_insn_and_split "*movti_internal"
[(set (match_operand:TI 0 "nonimmediate_operand" "=r,r,m")
- (match_operand:TI 1 "general_operand" "ri,m,r"))
- (clobber (match_scratch:DI 2 "=X,&r,&r"))]
+ (match_operand:TI 1 "general_operand" "ri,m,r"))]
"ia64_move_ok (operands[0], operands[1])"
"#"
"reload_completed"
[(set_attr "itanium_class" "unknown")
(set_attr "predicable" "no")])
-(define_expand "reload_inti"
- [(parallel [(set (match_operand:TI 0 "register_operand" "=r")
- (match_operand:TI 1 "memory_operand" "m"))
- (clobber (match_operand:DI 2 "register_operand" "=&r"))])]
- ""
- "")
-
-(define_expand "reload_outti"
- [(parallel [(set (match_operand:TI 0 "memory_operand" "=m")
- (match_operand:TI 1 "register_operand" "r"))
- (clobber (match_operand:DI 2 "register_operand" "=&r"))])]
- ""
- "")
-
;; Floating Point Moves
;;
;; Note - Patterns for SF mode moves are compulsory, but
[(set_attr "itanium_class" "fmisc,fld,stf")])
;; Better code generation via insns that deal with TFmode register pairs
-;; directly.
-;; With no offsettable memory references, we've got to have a scratch
-;; around to play with the second word.
+;; directly. Same concerns apply as for TImode.
(define_expand "movtf"
- [(parallel [(set (match_operand:TF 0 "general_operand" "")
- (match_operand:TF 1 "general_operand" ""))
- (clobber (match_scratch:DI 2 ""))])]
+ [(set (match_operand:TF 0 "general_operand" "")
+ (match_operand:TF 1 "general_operand" ""))]
""
{
rtx op1 = ia64_expand_move (operands[0], operands[1]);
(define_insn_and_split "*movtf_internal"
[(set (match_operand:TF 0 "nonimmediate_operand" "=r,r,m")
- (match_operand:TF 1 "general_operand" "ri,m,r"))
- (clobber (match_scratch:DI 2 "=X,&r,&r"))]
+ (match_operand:TF 1 "general_operand" "ri,m,r"))]
"ia64_move_ok (operands[0], operands[1])"
"#"
"reload_completed"
[(set_attr "itanium_class" "unknown")
(set_attr "predicable" "no")])
-(define_expand "reload_intf"
- [(parallel [(set (match_operand:TF 0 "register_operand" "=r")
- (match_operand:TF 1 "memory_operand" "m"))
- (clobber (match_operand:DI 2 "register_operand" "=&r"))])]
- ""
- "")
-
-(define_expand "reload_outtf"
- [(parallel [(set (match_operand:TF 0 "memory_operand" "=m")
- (match_operand:TF 1 "register_operand" "r"))
- (clobber (match_operand:DI 2 "register_operand" "=&r"))])]
- ""
- "")
\f
;; ::::::::::::::::::::
;; ::
git://gcc.gnu.org / gcc.git / commitdiff