combine.c (distribute_notes): Place REG_LABEL also where REG_EQUAL indicates.

        * combine.c (distribute_notes): Place REG_LABEL also where
        REG_EQUAL indicates.

From-SVN: r25984

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 839469c9d04feed0f2d82bc26964b0eff924bd95..bd7977526b9102b81afb2458df592dd31c906e00 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+Thu Mar 25 16:53:53 1999  Richard Henderson  <rth@cygnus.com>
+
+       * combine.c (distribute_notes): Place REG_LABEL also where
+       REG_EQUAL indicates.
+
 Thu Mar 25 12:46:37 1999  Jim Wilson  <wilson@cygnus.com>
 
        * a29k/a29k.h (TARGET_SWITCHES): Add doc strings.

diff --git a/gcc/combine.c b/gcc/combine.c
index e0a162ac2b7283138a07ee47994f320a7832ecda..0b64a86a548cea520f790ed0b947e1beb20399c2 100644 (file)
--- a/gcc/combine.c
+++ b/gcc/combine.c
@@ -11508,7 +11508,6 @@ distribute_notes (notes, from_insn, i3, i2, elim_i2, elim_i1)
 
        case REG_INC:
        case REG_NO_CONFLICT:
-       case REG_LABEL:
          /* These notes say something about how a register is used.  They must
             be present on any use of the register in I2 or I3.  */
          if (reg_mentioned_p (XEXP (note, 0), PATTERN (i3)))
@@ -11523,6 +11522,30 @@ distribute_notes (notes, from_insn, i3, i2, elim_i2, elim_i1)
            }
          break;
 
+       case REG_LABEL:
+         /* This can show up in several ways -- either directly in the
+            pattern, or hidden off in the constant pool with (or without?)
+            a REG_EQUAL note.  */
+         /* ??? Ignore the without-reg_equal-note problem for now.  */
+         if (reg_mentioned_p (XEXP (note, 0), PATTERN (i3))
+             || ((tem = find_reg_note (i3, REG_EQUAL, NULL_RTX))
+                 && GET_CODE (XEXP (tem, 0)) == LABEL_REF
+                 && XEXP (XEXP (tem, 0), 0) == XEXP (note, 0)))
+           place = i3;
+
+         if (i2
+             && (reg_mentioned_p (XEXP (note, 0), PATTERN (i2))
+                 || ((tem = find_reg_note (i2, REG_EQUAL, NULL_RTX))
+                     && GET_CODE (XEXP (tem, 0)) == LABEL_REF
+                     && XEXP (XEXP (tem, 0), 0) == XEXP (note, 0))))
+           {
+             if (place)
+               place2 = i2;
+             else
+               place = i2;
+           }
+         break;
+
        case REG_WAS_0:
          /* It is too much trouble to try to see if this note is still
             correct in all situations.  It is better to simply delete it.  */