expr.c (expand_expr): Change ">" to ">=" making MOVE_RATIO use consistent.

        * expr.c (expand_expr): Change ">" to ">=" making MOVE_RATIO use
        consistent.
        * tm.texi (Costs): Say MOVE_RATIO is number of mem-mem move
        *sequences* *below* which scalar moves will be used.

From-SVN: r22107

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 159983f591fca991700e467ab4a1ead00ebd61fb..7af6216503aa1c51b315c8babeab034398b92291 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,10 @@
+Sun Aug 30 20:19:43 1998  Hans-Peter Nilsson  <hp@axis.se>
+
+       * expr.c (expand_expr): Change ">" to ">=" making MOVE_RATIO use
+       consistent.
+       * tm.texi (Costs): Say MOVE_RATIO is number of mem-mem move
+       *sequences* *below* which scalar moves will be used.
+
 Sun Aug 30 17:18:43 1998  Jeffrey A Law  (law@cygnus.com)
 
        * collect2.c (mktemp): Delete unused declaration.

diff --git a/gcc/expr.c b/gcc/expr.c
index 22fc5f73e79e89f409f6321729274946897af0d2..03901266ba05c77bbc924cedc14fe01643115273 100644 (file)
--- a/gcc/expr.c
+++ b/gcc/expr.c
@@ -5889,7 +5889,7 @@ expand_expr (exp, target, tmode, modifier)
                        && (move_by_pieces_ninsns
                            (TREE_INT_CST_LOW (TYPE_SIZE (type))/BITS_PER_UNIT,
                             TYPE_ALIGN (type) / BITS_PER_UNIT)
-                           > MOVE_RATIO)
+                           >= MOVE_RATIO)
                        && ! mostly_zeros_p (exp))))
               || (modifier == EXPAND_INITIALIZER && TREE_CONSTANT (exp)))
        {

diff --git a/gcc/tm.texi b/gcc/tm.texi
index bf9aa4a05cf98cc6a7028655748c56f95f55ead7..2f7217672643a986efe60ee401c2094b6b48435a 100644 (file)
--- a/gcc/tm.texi
+++ b/gcc/tm.texi
@@ -4727,10 +4727,14 @@ than good.)
 
 @findex MOVE_RATIO
 @item MOVE_RATIO
-The number of scalar move insns which should be generated instead of a
+The threshold of number of scalar memory-to-memory move insns, @emph{below}
+which a sequence of insns  should be generated instead of a
 string move insn or a library call.  Increasing the value will always
 make code faster, but eventually incurs high cost in increased code size.
 
+Note that on machines with no memory-to-memory move insns, this macro denotes
+the corresponding number of memory-to-memory @emph{sequences}.
+
 If you don't define this, a reasonable default is used.
 
 @findex NO_FUNCTION_CSE