Fix 43484, swap registers if one is R0 for multiword moves

From-SVN: r157709

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index e6d05fe1671fcb59622c835357109fde3e9e132d..d2872bc3e0dfff4701d26d0b3e86e9344cafc180 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2010-03-24  Michael Meissner  <meissner@linux.vnet.ibm.com>
+
+       PR target/43484
+       * config/rs6000/rs6000.c (rs6000_split_multireg_move): If r0 is
+       used in reg+reg addressing, swap registers.
+
 2010-03-24  Jakub Jelinek  <jakub@redhat.com>
 
        PR debug/43293

diff --git a/gcc/config/rs6000/rs6000.c b/gcc/config/rs6000/rs6000.c
index ab48e82d9fc7ab16246df71a18a503b751d29385..98b4d9425417192733d1cec4532d1b417bb51ee9 100644 (file)
--- a/gcc/config/rs6000/rs6000.c
+++ b/gcc/config/rs6000/rs6000.c
@@ -16832,6 +16832,16 @@ rs6000_split_multireg_move (rtx dst, rtx src)
                {
                  rtx basereg = XEXP (XEXP (dst, 0), 0);
                  rtx offsetreg = XEXP (XEXP (dst, 0), 1);
+                 gcc_assert (GET_CODE (XEXP (dst, 0)) == PLUS
+                             && REG_P (basereg)
+                             && REG_P (offsetreg)
+                             && REGNO (basereg) != REGNO (offsetreg));
+                 if (REGNO (basereg) == 0)
+                   {
+                     rtx tmp = offsetreg;
+                     offsetreg = basereg;
+                     basereg = tmp;
+                   }
                  emit_insn (gen_add3_insn (basereg, basereg, offsetreg));
                  restore_basereg = gen_sub3_insn (basereg, basereg, offsetreg);
                  dst = replace_equiv_address (dst, basereg);