2005-06-09 Adrian Straetling <straetling@de.ibm.com>

	* target.h (insn_valid_within_doloop): Rename into
	"invalid_within_doloop".  Change return type to "const char *".
	Update Comment.
	* targhooks.h (default_insn_valid_within_doloop): Rename into
	"default_invalid_within_doloop".
	* targhooks.c (default_insn_valid_within_doloop): Likewise.
	Update Comment.
	* target-def.h (TARGET_INSN_VALID_WITHIN_DOLOOP): Rename target hook
	into "TARGET_INVALID_WITHIN_DOLOOP". Default it to
	"default_invalid_within_doloop".
	* hooks.c (hook_constcharptr_rtx_null): New function.
	(hook_bool_rtx_true): Remove.
	* hooks.h (hook_constcharptr_rtx_null): Declare.
	(hook_bool_rtx_true): Remove.
	* loop-doloop.c (doloop_valid_p): Temporarily store return value of
	"invalid_within_doloop" and print error message if non-null.
	Update Comment.
	* doc/tm.texi: Update documentation.
	* config/s390/s390.c: Adjust to new hook name and new default hook.
	* config/rs6000/rs6000.c: (rs6000_insn_valid_within_doloop): Rename
	into "rs6000_invalid_within_doloop".
	(rs6000_invalid_within_doloop): Change return type to "static const
	char *" and replace return values.  Update Comment.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@100797 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 10 insertions, 16 deletions

diff --git a/gcc/targhooks.c b/gcc/targhooks.c
index 42992b78c34..1de5809db13 100644
--- a/gcc/targhooks.c
+++ b/gcc/targhooks.c
@@ -262,34 +262,28 @@ default_scalar_mode_supported_p (enum machine_mode mode)
     }
 }
 
-/* TRUE if INSN insn is valid within a low-overhead loop.
+/* NULL if INSN insn is valid within a low-overhead loop, otherwise returns
+   an error message.
   
    This function checks whether a given INSN is valid within a low-overhead
-   loop.  A called function may clobber any special registers required for
-   low-overhead looping. Additionally, some targets (eg, PPC) use the count
+   loop.  If INSN is invalid it returns the reason for that, otherwise it
+   returns NULL. A called function may clobber any special registers required
+   for low-overhead looping. Additionally, some targets (eg, PPC) use the count
    register for branch on table instructions. We reject the doloop pattern in
    these cases.  */
 
-bool 
-default_insn_valid_within_doloop (rtx insn)
+const char *
+default_invalid_within_doloop (rtx insn)
 {
   if (CALL_P (insn))
-    {
-      if (dump_file)
-	fprintf (dump_file, "Doloop: Function call in loop.\n");
-	return false;
-    }
+    return "Function call in loop.";
   
   if (JUMP_P (insn)
       && (GET_CODE (PATTERN (insn)) == ADDR_DIFF_VEC
 	  || GET_CODE (PATTERN (insn)) == ADDR_VEC))
-    {
-      if (dump_file)
-	fprintf (dump_file, "Doloop: Computed branch in the loop.\n");
-      return false;
-    }
+    return "Computed branch in the loop.";
   
-  return true;
+  return NULL;
 }
 
 bool