builtins.c (expand_builtin_memcpy): Remove endp argument and endp != 0 handling.

	* builtins.c (expand_builtin_memcpy): Remove endp argument and endp
	!= 0 handling.  Pass 0 to store_by_pieces.
	(expand_builtin_mempcpy): Add endp argument.  Don't call
	expand_builtin_memcpy, call store_by_pieces resp. move_by_pieces
	directly.  If ignoring result, only do expand_call.
	(expand_builtin_stpcpy): Likewise.  Call expand_builtin_mempcpy
	otherwise.
	(expand_builtin_strncpy, expand_builtin_memset): Adjust
	store_by_pices callers.
	(expand_builtin): Adjust expand_builtin_memcpy and
	expand_builtin_mempcpy callers.
	* expr.c (can_move_by_pieces): New function.
	(move_by_pieces): Add endp argument, return to resp. memory at end
	or one byte earlier depending on endp.
	(store_by_pieces): Likewise.
	(emit_block_move): Adjust call to move_by_pieces.
	(emit_push_insn): Adjust move_by_pieces caller.
	* expr.h (can_move_by_pieces): New prototype.
	(store_by_pieces): Adjust prototypes.
	* rtl.h (move_by_pieces): Adjust prototype.
	* config/mips/mips.c (expand_block_move): Adjust move_by_pieces
	caller.

	* gcc.c-torture/execute/builtins/string-4.c (main_test): Remove
	mempcpy test with post-increments.
	* gcc.c-torture/execute/string-opt-3.c: New test.
	* gcc.dg/string-opt-1.c: New test.

From-SVN: r67358

1 files changed, 89 insertions, 9 deletions

diff --git a/gcc/expr.c b/gcc/expr.c
index e3872e8e269..f340335515b 100644
--- a/gcc/expr.c
+++ b/gcc/expr.c
@@ -1456,6 +1456,18 @@ convert_modes (mode, oldmode, x, unsignedp)
 
 #define STORE_MAX_PIECES  MIN (MOVE_MAX_PIECES, 2 * sizeof (HOST_WIDE_INT))
 
+/* Determine whether the LEN bytes can be moved by using several move
+   instructions.  Return nonzero if a call to move_by_pieces should
+   succeed.  */
+
+int
+can_move_by_pieces (len, align)
+     unsigned HOST_WIDE_INT len;
+     unsigned int align;
+{
+  return MOVE_BY_PIECES_P (len, align);
+}
+
 /* Generate several move instructions to copy LEN bytes from block FROM to
    block TO.  (These are MEM rtx's with BLKmode).  The caller must pass FROM
    and TO through protect_from_queue before calling.
@@ -1463,13 +1475,18 @@ convert_modes (mode, oldmode, x, unsignedp)
    If PUSH_ROUNDING is defined and TO is NULL, emit_single_push_insn is
    used to push FROM to the stack.
 
-   ALIGN is maximum stack alignment we can assume.  */
+   ALIGN is maximum stack alignment we can assume.
 
-void
-move_by_pieces (to, from, len, align)
+   If ENDP is 0 return to, if ENDP is 1 return memory at the end ala
+   mempcpy, and if ENDP is 2 return memory the end minus one byte ala
+   stpcpy.  */
+
+rtx
+move_by_pieces (to, from, len, align, endp)
      rtx to, from;
      unsigned HOST_WIDE_INT len;
      unsigned int align;
+     int endp;
 {
   struct move_by_pieces data;
   rtx to_addr, from_addr = XEXP (from, 0);
@@ -1583,6 +1600,36 @@ move_by_pieces (to, from, len, align)
   /* The code above should have handled everything.  */
   if (data.len > 0)
     abort ();
+
+  if (endp)
+    {
+      rtx to1;
+
+      if (data.reverse)
+	abort ();
+      if (data.autinc_to)
+	{
+	  if (endp == 2)
+	    {
+	      if (HAVE_POST_INCREMENT && data.explicit_inc_to > 0)
+		emit_insn (gen_add2_insn (data.to_addr, constm1_rtx));
+	      else
+		data.to_addr = copy_addr_to_reg (plus_constant (data.to_addr,
+								-1));
+	    }
+	  to1 = adjust_automodify_address (data.to, QImode, data.to_addr,
+					   data.offset);
+	}
+      else
+	{
+	  if (endp == 2)
+	    --data.offset;
+	  to1 = adjust_address (data.to, QImode, data.offset);
+	}
+      return to1;
+    }
+  else
+    return data.to;
 }
 
 /* Return number of insns required to move L bytes by pieces.
@@ -1760,7 +1807,7 @@ emit_block_move (x, y, size, method)
     }
 
   if (GET_CODE (size) == CONST_INT && MOVE_BY_PIECES_P (INTVAL (size), align))
-    move_by_pieces (x, y, INTVAL (size), align);
+    move_by_pieces (x, y, INTVAL (size), align, 0);
   else if (emit_block_move_via_movstr (x, y, size, align))
     ;
   else if (may_use_call)
@@ -2014,7 +2061,7 @@ init_block_move_fn (asmspec)
 {
   if (!block_move_fn)
     {
-      tree fn, args;
+      tree args, fn;
 
       if (TARGET_MEM_FUNCTIONS)
 	{
@@ -2738,15 +2785,19 @@ can_store_by_pieces (len, constfun, constfundata, align)
 /* Generate several move instructions to store LEN bytes generated by
    CONSTFUN to block TO.  (A MEM rtx with BLKmode).  CONSTFUNDATA is a
    pointer which will be passed as argument in every CONSTFUN call.
-   ALIGN is maximum alignment we can assume.  */
+   ALIGN is maximum alignment we can assume.
+   If ENDP is 0 return to, if ENDP is 1 return memory at the end ala
+   mempcpy, and if ENDP is 2 return memory the end minus one byte ala
+   stpcpy.  */
 
-void
-store_by_pieces (to, len, constfun, constfundata, align)
+rtx
+store_by_pieces (to, len, constfun, constfundata, align, endp)
      rtx to;
      unsigned HOST_WIDE_INT len;
      rtx (*constfun) PARAMS ((PTR, HOST_WIDE_INT, enum machine_mode));
      PTR constfundata;
      unsigned int align;
+     int endp;
 {
   struct store_by_pieces data;
 
@@ -2758,6 +2809,35 @@ store_by_pieces (to, len, constfun, constfundata, align)
   data.len = len;
   data.to = to;
   store_by_pieces_1 (&data, align);
+  if (endp)
+    {
+      rtx to1;
+
+      if (data.reverse)
+	abort ();
+      if (data.autinc_to)
+	{
+	  if (endp == 2)
+	    {
+	      if (HAVE_POST_INCREMENT && data.explicit_inc_to > 0)
+		emit_insn (gen_add2_insn (data.to_addr, constm1_rtx));
+	      else
+		data.to_addr = copy_addr_to_reg (plus_constant (data.to_addr,
+								-1));
+	    }
+	  to1 = adjust_automodify_address (data.to, QImode, data.to_addr,
+					   data.offset);
+	}
+      else
+	{
+	  if (endp == 2)
+	    --data.offset;
+	  to1 = adjust_address (data.to, QImode, data.offset);
+	}
+      return to1;
+    }
+  else
+    return data.to;
 }
 
 /* Generate several move instructions to clear LEN bytes of block TO.  (A MEM
@@ -3872,7 +3952,7 @@ emit_push_insn (x, mode, type, size, align, partial, reg, extra,
 	      && where_pad != none && where_pad != stack_direction)
 	    anti_adjust_stack (GEN_INT (extra));
 
-	  move_by_pieces (NULL, xinner, INTVAL (size) - used, align);
+	  move_by_pieces (NULL, xinner, INTVAL (size) - used, align, 0);
 	}
       else
 #endif /* PUSH_ROUNDING  */