Allow expand_block_move() to fail and have the MI code generate the memcpy

call, rather than doing it ourselves.

gnu/gcc/gcc/config/m88k/m88k-protos.h

@@ -24,7 +24,7 @@ Boston, MA 02110-1301, USA.  */
 #ifdef RTX_CODE
 extern void m88k_emit_bcnd (enum rtx_code, rtx);
 extern void m88k_emit_trailing_label (rtx);
-extern void expand_block_move (rtx *);
+extern int expand_block_move (rtx *);
 extern void print_operand (FILE *, rtx, int);
 extern void print_operand_address (FILE *, rtx);
 extern const char *output_load_const_int (enum machine_mode, rtx *);

gnu/gcc/gcc/config/m88k/m88k.c

@@ -689,14 +689,15 @@ static const enum machine_mode mode_from_align[] =
 
 static void block_move_sequence (rtx, rtx, int, int);
 
-/* Emit code to perform a block move.  Choose the best method.
+/* Emit code to perform a block move, and return 1 if successful.
+   Return 0 if we should let the compiler generate a call to memcpy().
 
    OPERANDS[0] is the destination.
    OPERANDS[1] is the source.
    OPERANDS[2] is the size.
    OPERANDS[3] is the alignment safe to use.  */
 
-void
+int
 expand_block_move (rtx *operands)
 {
   rtx dest, src;
@@ -704,8 +705,11 @@ expand_block_move (rtx *operands)
   int constp = CONST_INT_P (operands[2]);
   int bytes = constp ? INTVAL (operands[2]) : 0;
 
-  if (constp && bytes <= 0)
-    return;
+  if (!constp)
+    return 0;
+
+  if (bytes <= 0)
+    return 1; /* nothing to do.  */
 
   /* Determine machine mode to do move with.  */
   if (align > 4 && !TARGET_88110)
@@ -716,19 +720,11 @@ expand_block_move (rtx *operands)
   dest = operands[0];
   src = operands[1];
 
-  if (constp && bytes <= (optimize_size ? 3 : 6) * align)
-    {
-      block_move_sequence (dest, src, bytes, align);
-      return;
-    }
+  if (bytes > (optimize_size ? 3 : 6) * align)
+    return 0;
 
-  emit_library_call (gen_rtx_SYMBOL_REF (Pmode, "memcpy"), 0,
-		     VOIDmode, 3,
-		     dest, Pmode,
-		     src, Pmode,
-		     convert_to_mode (TYPE_MODE (sizetype), operands[2],
-				      TYPE_UNSIGNED (sizetype)),
-		     TYPE_MODE (sizetype));
+  block_move_sequence (dest, src, bytes, align);
+  return 1;
 }
 
 /* Emit code to perform a block move with an offset sequence of ld/st
@@ -741,13 +737,13 @@ block_move_sequence (rtx dest_mem, rtx src_mem, int size, int align)
   rtx temp[2];
   enum machine_mode mode[2];
   int amount[2];
-  int active[2];
+  bool active[2];
   int phase = 0;
   int next;
   int offset_ld = 0;
   int offset_st = 0;
 
-  active[0] = active[1] = FALSE;
+  active[0] = active[1] = false;
 
   /* Establish parameters for the first load and for the second load if
      it is known to be the same mode as the first.  */
@@ -763,7 +759,7 @@ block_move_sequence (rtx dest_mem, rtx src_mem, int size, int align)
   do
     {
       next = phase;
-      phase = !phase;
+      phase ^= 1;
 
       if (size > 0)
 	{
@@ -2021,7 +2017,7 @@ m88k_emit_bcnd (enum rtx_code op, rtx label)
       value = INTVAL (constant);
 
       /* Perform an arithmetic computation to make the compared-to value
-	 zero, but avoid loosing if the bcnd is later changed into sxx.  */
+	 zero, but avoid losing if the bcnd is later changed into sxx.  */
       if (SMALL_INTVAL (value))
 	emit_jump_insn (gen_bxx (m88k_emit_test (op, VOIDmode), label));
       else

gnu/gcc/gcc/config/m88k/m88k.md

@@ -466,9 +466,8 @@
 ;; Improve logical operations on compare words
 ;;
 ;; We define all logical operations on CCmode values to preserve the pairwise
-;; relationship of the compare bits.  This allows a future branch prediction
+;; relationship of the compare bits.  This allows the future branch prediction
 ;; pass the degree of freedom needed to change and/bb0-le into or/bb1-gt.
-;; THIS IS CURRENTLY FALSE! 
 ;;
 ;; Opportunities arise when conditional expressions using && and || are made
 ;; unconditional.  When these are used to branch, the sequence is
@@ -2123,16 +2122,18 @@
 
 ;; String/block move insn.  See m88k.c for details.
 
-(define_expand "movstrsi"
-  [(parallel [(set (mem:BLK (match_operand:BLK 0 "" ""))
-		   (mem:BLK (match_operand:BLK 1 "" "")))
+(define_expand "movmemsi"
+  [(parallel [(set (match_operand:BLK 0 "memory_operand" "")
+		   (match_operand:BLK 1 "memory_operand" ""))
 	      (use (match_operand:SI 2 "arith32_operand" ""))
 	      (use (match_operand:SI 3 "immediate_operand" ""))])]
   ""
   "
 {
-  expand_block_move (operands);
-  DONE;
+  if (expand_block_move (operands))
+    DONE;
+  else
+    FAIL;
 }")
 
 ;;- zero extension instructions
@@ -3756,13 +3757,15 @@
    (clobber (reg:SI 1))]
   ""
 {
+  /* This is safe as this insn is of type "weird" and thus not considered
+     to have a delay slot of its own.  */
   if (flag_delayed_branch)
     return "bsr.n %0e\;lda %#r1,%#r1[%1]";
-  m88k_case_index = REGNO (operands[1]);
+  m88k_case_index = REGNO (operands[1]); /* for ASM_OUTPUT_CASE_END */
   return "bsr %0e";
 }
   [(set_attr "type" "weird")
-   (set_attr "length" "12")]) ; Including the "jmp r1".
+   (set_attr "length" "12")]) ; includes ASM_OUTPUT_CASE_END output
 
 ;;- jump to subroutine
 (define_expand "call"