flow.c (invalidate_from_autoinc): New function.

        * flow.c (invalidate_from_autoinc): New function.
        (mark_set_1, mark_used_regs): Use it.

From-SVN: r24781

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index d32ef1b..6326ec0 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -30,6 +30,9 @@ Tue Jan 19 16:37:36 1999  Richard Henderson  <rth@cygnus.com>
 
 Tue Jan 19 15:00:10 1999  Jeffrey A Law  (law@cygnus.com)
 
+       * flow.c (invalidate_from_autoinc): New function.
+       (mark_set_1, mark_used_regs): Use it.
+
        * Makefile.in (protoize.o, unprotoize.o): Depend on Makefile.
 
 1999-01-19  Vladimir N. Makarov  <vmakarov@cygnus.com>

diff --git a/gcc/flow.c b/gcc/flow.c
index aa72c6a..cd5de38 100644 (file)
--- a/gcc/flow.c
+++ b/gcc/flow.c
@@ -295,6 +295,7 @@ static void count_reg_sets_1                PROTO ((rtx));
 static void count_reg_sets             PROTO ((rtx));
 static void count_reg_references       PROTO ((rtx));
 static void notice_stack_pointer_modification PROTO ((rtx, rtx));
+static void invalidate_mems_from_autoinc       PROTO ((rtx));
 \f
 /* Find basic blocks of the current function.
    F is the first insn of the function and NREGS the number of register numbers
@@ -2225,6 +2226,39 @@ regno_clobbered_at_setjmp (regno)
          && REGNO_REG_SET_P (regs_live_at_setjmp, regno));
 }
 \f
+/* INSN references memory, possibly using autoincrement addressing modes.
+   Find any entries on the mem_set_list that need to be invalidated due
+   to an address change.  */
+static void
+invalidate_mems_from_autoinc (insn)
+     rtx insn;
+{
+  rtx note = REG_NOTES (insn);
+  for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
+    {
+      if (REG_NOTE_KIND (note) == REG_INC)
+        {
+          rtx temp = mem_set_list;
+          rtx prev = NULL_RTX;
+
+          while (temp)
+           {
+             if (reg_overlap_mentioned_p (XEXP (note, 0), XEXP (temp, 0)))
+               {
+                 /* Splice temp out of list.  */
+                 if (prev)
+                   XEXP (prev, 1) = XEXP (temp, 1);
+                 else
+                   mem_set_list = XEXP (temp, 1);
+               }
+             else
+               prev = temp;
+              temp = XEXP (temp, 1);
+           }
+       }
+    }
+}
+
 /* Process the registers that are set within X.
    Their bits are set to 1 in the regset DEAD,
    because they are dead prior to this insn.
@@ -2327,7 +2361,13 @@ mark_set_1 (needed, dead, x, insn, significant)
          temp = XEXP (temp, 1);
        }
     }
-    
+
+  /* If the memory reference had embedded side effects (autoincrement
+     address modes.  Then we may need to kill some entries on the
+     memory set list.  */
+  if (insn && GET_CODE (reg) == MEM)
+    invalidate_mems_from_autoinc (insn);
+
   if (GET_CODE (reg) == MEM && ! side_effects_p (reg)
       /* There are no REG_INC notes for SP, so we can't assume we'll see 
         everything that invalidates it.  To be safe, don't eliminate any
@@ -2750,6 +2790,12 @@ mark_used_regs (needed, live, x, final, insn)
            }
        }
 
+      /* If the memory reference had embedded side effects (autoincrement
+        address modes.  Then we may need to kill some entries on the
+        memory set list.  */
+      if (insn)
+       invalidate_mems_from_autoinc (insn);
+
 #ifdef AUTO_INC_DEC
       if (final)
        find_auto_inc (needed, x, insn);