2007-08-24 Sandra Loosemore <sandra@codesourcery.com>

            Nigel Stephens <nigel@mips.com>

	PR target/11787

	gcc/

	* doc/tm.texi (SET_RATIO, SET_BY_PIECES_P): Document new macros.
	(STORE_BY_PIECES_P): No longer applies to __builtin_memset.
	* expr.c (SET_BY_PIECES_P): Define.
	(can_store_by_pieces, store_by_pieces): Add MEMSETP argument; use
	it to decide whether to use SET_BY_PIECES_P or STORE_BY_PIECES_P.
	(store_expr):  Pass MEMSETP argument to can_store_by_pieces and
	store_by_pieces.
	* expr.h (SET_RATIO): Define.
	(can_store_by_pieces, store_by_pieces):	Update prototypes.
	* builtins.c (expand_builtin_memcpy): Pass MEMSETP argument to
	can_store_by_pieces/store_by_pieces.
	(expand_builtin_memcpy_args): Likewise.
	(expand_builtin_strncpy): Likewise.
	(expand_builtin_memset_args): Likewise.  Also remove special case
	for optimize_size so that can_store_by_pieces/SET_BY_PIECES_P can
	decide what to do instead.
	* value-prof.c (tree_stringops_transform): Pass MEMSETP argument
	to can_store_by_pieces.

	* config/sh/sh.h (SET_BY_PIECES_P): Clone from STORE_BY_PIECES_P.
	* config/s390/s390.h (SET_BY_PIECES_P): Likewise.

	* config/mips/mips.opt (mmemcpy): Change from Var to Mask.
	* config/mips/mips.c (override_options): Make -Os default to -mmemcpy.
	* config/mips/mips.h (MIPS_CALL_RATIO): Define.
	(MOVE_RATIO, CLEAR_RATIO, SET_RATIO): Define.
	(STORE_BY_PIECES_P): Define.


git-svn-id: https://gcc.gnu.org/svn/gcc/trunk@127790 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 25 insertions, 11 deletions

diff --git a/gcc/expr.c b/gcc/expr.c
index 97116b33daa..244604000a9 100644
--- a/gcc/expr.c
+++ b/gcc/expr.c
@@ -186,8 +186,15 @@ static bool float_extend_from_mem[NUM_MACHINE_MODES][NUM_MACHINE_MODES];
 #endif
 
 /* This macro is used to determine whether store_by_pieces should be
-   called to "memset" storage with byte values other than zero, or
-   to "memcpy" storage when the source is a constant string.  */
+   called to "memset" storage with byte values other than zero.  */
+#ifndef SET_BY_PIECES_P
+#define SET_BY_PIECES_P(SIZE, ALIGN) \
+  (move_by_pieces_ninsns (SIZE, ALIGN, STORE_MAX_PIECES + 1) \
+   < (unsigned int) SET_RATIO)
+#endif
+
+/* This macro is used to determine whether store_by_pieces should be
+   called to "memcpy" storage when the source is a constant string.  */
 #ifndef STORE_BY_PIECES_P
 #define STORE_BY_PIECES_P(SIZE, ALIGN) \
   (move_by_pieces_ninsns (SIZE, ALIGN, STORE_MAX_PIECES + 1) \
@@ -2191,13 +2198,14 @@ use_group_regs (rtx *call_fusage, rtx regs)
 /* Determine whether the LEN bytes generated by CONSTFUN can be
    stored to memory using several move instructions.  CONSTFUNDATA is
    a pointer which will be passed as argument in every CONSTFUN call.
-   ALIGN is maximum alignment we can assume.  Return nonzero if a
-   call to store_by_pieces should succeed.  */
+   ALIGN is maximum alignment we can assume.  MEMSETP is true if this is
+   a memset operation and false if it's a copy of a constant string.
+   Return nonzero if a call to store_by_pieces should succeed.  */
 
 int
 can_store_by_pieces (unsigned HOST_WIDE_INT len,
 		     rtx (*constfun) (void *, HOST_WIDE_INT, enum machine_mode),
-		     void *constfundata, unsigned int align)
+		     void *constfundata, unsigned int align, bool memsetp)
 {
   unsigned HOST_WIDE_INT l;
   unsigned int max_size;
@@ -2210,7 +2218,9 @@ can_store_by_pieces (unsigned HOST_WIDE_INT len,
   if (len == 0)
     return 1;
 
-  if (! STORE_BY_PIECES_P (len, align))
+  if (! (memsetp 
+	 ? SET_BY_PIECES_P (len, align)
+	 : STORE_BY_PIECES_P (len, align)))
     return 0;
 
   tmode = mode_for_size (STORE_MAX_PIECES * BITS_PER_UNIT, MODE_INT, 1);
@@ -2285,7 +2295,8 @@ can_store_by_pieces (unsigned HOST_WIDE_INT len,
 /* 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.  MEMSETP is true if this is
+   a memset operation and false if it's a copy of a constant string.
    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.  */
@@ -2293,7 +2304,7 @@ can_store_by_pieces (unsigned HOST_WIDE_INT len,
 rtx
 store_by_pieces (rtx to, unsigned HOST_WIDE_INT len,
 		 rtx (*constfun) (void *, HOST_WIDE_INT, enum machine_mode),
-		 void *constfundata, unsigned int align, int endp)
+		 void *constfundata, unsigned int align, bool memsetp, int endp)
 {
   struct store_by_pieces data;
 
@@ -2303,7 +2314,9 @@ store_by_pieces (rtx to, unsigned HOST_WIDE_INT len,
       return to;
     }
 
-  gcc_assert (STORE_BY_PIECES_P (len, align));
+  gcc_assert (memsetp
+	      ? SET_BY_PIECES_P (len, align)
+	      : STORE_BY_PIECES_P (len, align));
   data.constfun = constfun;
   data.constfundata = constfundata;
   data.len = len;
@@ -4498,7 +4511,7 @@ store_expr (tree exp, rtx target, int call_param_p, bool nontemporal)
       str_copy_len = MIN (str_copy_len, exp_len);
       if (!can_store_by_pieces (str_copy_len, builtin_strncpy_read_str,
 				(void *) TREE_STRING_POINTER (exp),
-				MEM_ALIGN (target)))
+				MEM_ALIGN (target), false))
 	goto normal_expr;
 
       dest_mem = target;
@@ -4507,7 +4520,8 @@ store_expr (tree exp, rtx target, int call_param_p, bool nontemporal)
 				  str_copy_len, builtin_strncpy_read_str,
 				  (void *) TREE_STRING_POINTER (exp),
 				  MEM_ALIGN (target),
-				  exp_len > str_copy_len ? 1 : 0);
+				  exp_len > str_copy_len ? 1 : 0,
+				  false);
       if (exp_len > str_copy_len)
 	clear_storage (dest_mem, GEN_INT (exp_len - str_copy_len),
 		       BLOCK_OP_NORMAL);