@@ -5291,12 +5291,13 @@ are the first two operands, and both are
@code{mem:BLK}s with an
address in mode @code{Pmode}.
The number of bytes to move is the third operand, in mode @var{m}.
-Usually, you specify @code{word_mode} for @var{m}. However, if you can
+Usually, you specify @code{Pmode} for @var{m}. However, if you can
generate better code knowing the range of valid lengths is smaller than
-those representable in a full word, you should provide a pattern with a
+those representable in a full Pmode pointer, you should provide
+a pattern with a
mode corresponding to the range of values you can handle efficiently
(e.g., @code{QImode} for values in the range 0--127; note we avoid numbers
-that appear negative) and also a pattern with @code{word_mode}.
+that appear negative) and also a pattern with @code{Pmode}.
The fourth operand is the known shared alignment of the source and
destination, in the form of a @code{const_int} rtx. Thus, if the
@@ -1297,11 +1297,12 @@ emit_block_move_via_movmem (rtx x, rtx y, rtx
size, unsigned int align,
/* We don't need MODE to be narrower than BITS_PER_HOST_WIDE_INT
here because if SIZE is less than the mode mask, as it is
returned by the macro, it will definitely be less than the
- actual mode mask. */
+ actual mode mask. Since SIZE is within the Pmode address
+ space, we limit MODE to Pmode. */
&& ((CONST_INT_P (size)
&& ((unsigned HOST_WIDE_INT) INTVAL (size)
<= (GET_MODE_MASK (mode) >> 1)))
- || GET_MODE_BITSIZE (mode) >= BITS_PER_WORD))
+ || GET_MODE_BITSIZE (mode) >= GET_MODE_BITSIZE (Pmode)))
{
struct expand_operand ops[6];