+2003-10-06 Eric Botcazou <ebotcazou@libertysurf.fr>
+
+ PR optimization/11637
+ * combine.c (adjust_for_new_dest): New function to adjust the
+ notes and LOG_LINKS when the dest of an insn has changed.
+ (try_combine): Use it when deleting the first insn of a two-insn
+ parallel or splitting a two-load parallel.
+
2003-10-06 Richard Sandiford <rsandifo@redhat.com>
* config/mips/mips.c (mips_classify_constant): Only allow UNSPECs
* config/mn10300/mn10300.md: Likewise.
* config/sh/sh.h: Likewise.
->>>>>>> 2.1294
2003-10-05 Richard Henderson <rth@redhat.com>
* tree-inline.c (remap_type): New.
return 0;
}
+/* Adjust INSN after we made a change to its destination.
+
+ Changing the destination can invalidate notes that say something about
+ the results of the insn and a LOG_LINK pointing to the insn. */
+
+static void
+adjust_for_new_dest (rtx insn)
+{
+ rtx *loc;
+
+ /* For notes, be conservative and simply remove them. */
+ loc = ®_NOTES (insn);
+ while (*loc)
+ {
+ enum reg_note kind = REG_NOTE_KIND (*loc);
+ if (kind == REG_EQUAL || kind == REG_EQUIV)
+ *loc = XEXP (*loc, 1);
+ else
+ loc = &XEXP (*loc, 1);
+ }
+
+ /* The new insn will have a destination that was previously the destination
+ of an insn just above it. Call distribute_links to make a LOG_LINK from
+ the next use of that destination. */
+ distribute_links (gen_rtx_INSN_LIST (VOIDmode, insn, NULL_RTX));
+}
+
/* Try to combine the insns I1 and I2 into I3.
Here I1 and I2 appear earlier than I3.
I1 can be zero; then we combine just I2 into I3.
{
newpat = XVECEXP (newpat, 0, 1);
insn_code_number = recog_for_combine (&newpat, i3, &new_i3_notes);
+
+ if (insn_code_number >= 0)
+ {
+ /* If we will be able to accept this, we have made a change to the
+ destination of I3. This requires us to do a few adjustments. */
+ PATTERN (i3) = newpat;
+ adjust_for_new_dest (i3);
+ }
}
/* If we were combining three insns and the result is a simple SET
rtx link;
/* If we will be able to accept this, we have made a change to the
- destination of I3. This can invalidate a LOG_LINKS pointing
- to I3. No other part of combine.c makes such a transformation.
-
- The new I3 will have a destination that was previously the
- destination of I1 or I2 and which was used in i2 or I3. Call
- distribute_links to make a LOG_LINK from the next use of
- that destination. */
-
+ destination of I3. This requires us to do a few adjustments. */
PATTERN (i3) = newpat;
- distribute_links (gen_rtx_INSN_LIST (VOIDmode, i3, NULL_RTX));
+ adjust_for_new_dest (i3);
/* I3 now uses what used to be its destination and which is
now I2's destination. That means we need a LOG_LINK from
}
\f
/* Similarly to above, distribute the LOG_LINKS that used to be present on
- I3, I2, and I1 to new locations. This is also called in one case to
- add a link pointing at I3 when I3's destination is changed. */
+ I3, I2, and I1 to new locations. This is also called to add a link
+ pointing at I3 when I3's destination is changed. */
static void
distribute_links (rtx links)