*** empty log message ***

From-SVN: r1162

diff --git a/gcc/cse.c b/gcc/cse.c
index c863d3c2f9fdcb7e4d1dc735a57e5fcae0949344..a54781e68e0f7882f410bcd353b7579cd8ac476c 100644 (file)
--- a/gcc/cse.c
+++ b/gcc/cse.c
@@ -4580,6 +4580,10 @@ fold_rtx (x, insn)
   switch (GET_RTX_CLASS (code))
     {
     case '1':
+      /* We can't simplify extension ops unless we know the original mode.  */
+      if ((code == ZERO_EXTEND || code == SIGN_EXTEND)
+         && mode_arg0 == VOIDmode)
+       break;
       new = simplify_unary_operation (code, mode,
                                      const_arg0 ? const_arg0 : folded_arg0,
                                      mode_arg0);
@@ -6630,6 +6634,17 @@ cse_process_notes (x, object)
        XEXP (x, 1) = cse_process_notes (XEXP (x, 1), 0);
       return x;
 
+    case SIGN_EXTEND:
+    case ZERO_EXTEND:
+      {
+       rtx new = cse_process_notes (XEXP (x, 0), object);
+       /* We don't substitute VOIDmode constants into these rtx,
+          since they would impede folding.  */
+       if (GET_MODE (new) != VOIDmode)
+         validate_change (object, &XEXP (x, 0), new, 0);
+       return x;
+      }
+
     case REG:
       i = reg_qty[REGNO (x)];
 
@@ -7599,6 +7614,7 @@ delete_dead_from_cse (insns, nreg)
   rtx insn;
   rtx tem;
   int i;
+  int in_libcall = 0;
 
   /* First count the number of times each register is used.  */
   bzero (counts, sizeof (int) * nreg);
@@ -7613,7 +7629,14 @@ delete_dead_from_cse (insns, nreg)
     {
       int live_insn = 0;
 
-      if (GET_CODE (PATTERN (insn)) == SET)
+      /* Don't delete any insns that are part of a libcall block.
+        Flow or loop might get confused if we did that.  */
+      if (find_reg_note (insn, REG_LIBCALL, 0))
+       in_libcall = 1;
+
+      if (in_libcall)
+       live_insn = 1;
+      else if (GET_CODE (PATTERN (insn)) == SET)
        {
          if (GET_CODE (SET_DEST (PATTERN (insn))) == REG
              && SET_DEST (PATTERN (insn)) == SET_SRC (PATTERN (insn)))
@@ -7665,16 +7688,17 @@ delete_dead_from_cse (insns, nreg)
        live_insn = 1;
 
       /* If this is a dead insn, delete it and show registers in it aren't
-        being used.  If this is the last insn of a libcall sequence, don't
-        delete it even if it is dead because we don't know how to do so
-        here.  */
+        being used.  */
 
-      if (! live_insn && ! find_reg_note (insn, REG_RETVAL, 0))
+      if (! live_insn)
        {
          count_reg_usage (insn, counts, -1);
          PUT_CODE (insn, NOTE);
          NOTE_SOURCE_FILE (insn) = 0;
          NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
        }
+
+      if (find_reg_note (insn, REG_RETVAL, 0))
+       in_libcall = 0;
     }
 }