Fix for an optimization bug that shows up on xscale.

Problem report and patch from
    http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view&pr=8896

diff --git a/sources/gcc-3.2.1-arm-xscale.patch b/sources/gcc-3.2.1-arm-xscale.patch
new file mode 100644 (file)
index 0000000..0d5588e
--- /dev/null
+++ b/sources/gcc-3.2.1-arm-xscale.patch
@@ -0,0 +1,21 @@
+--- gcc-3.2.1/gcc/reload1.c.orig       2002-10-10 09:40:20.000000000 -0600
++++ gcc-3.2.1/gcc/reload1.c    2003-01-30 12:15:05.000000000 -0700
+@@ -8674,7 +8674,9 @@
+        ... (MEM (PLUS (REGZ) (REGY)))... .
+ 
+        First, check that we have (set (REGX) (PLUS (REGX) (REGY)))
+-       and that we know all uses of REGX before it dies.  */
++       and that we know all uses of REGX before it dies. 
++       Also, explicitly check that REGX != REGY; our life information
++       does not yet show whether REGY changes in this insn.  */
+       set = single_set (insn);
+       if (set != NULL_RTX
+         && GET_CODE (SET_DEST (set)) == REG
+@@ -8684,6 +8686,7 @@
+         && GET_CODE (SET_SRC (set)) == PLUS
+         && GET_CODE (XEXP (SET_SRC (set), 1)) == REG
+         && rtx_equal_p (XEXP (SET_SRC (set), 0), SET_DEST (set))
++        && !rtx_equal_p (XEXP (SET_SRC (set), 1), SET_DEST (set))
+         && last_label_ruid < reg_state[REGNO (SET_DEST (set))].use_ruid)
+       {
+         rtx reg = SET_DEST (set);