Alternate patch eliminating MD_CALL_PROTOTYPES

[Zack Weinberg <zack at wolery dot cumb dot org>]

This is an alternate possibility for eliminating MD_CALL_PROTOTYPES,
suggested by rth: put wrapper macros around the problematic
generators.  Its advantage is that it requires no changes to
arch-specific code.  Its disadvantage is that it's a bit uglier.
I'm agnostic here; either approach works.

This has been tested on i386-linux, with prototype warnings enabled.

zw

	* Makefile.in (WARN_CFLAGS): Add -Wstrict-prototypes
	-Wmissing-prototypes.
	* gcc.texi: Remove explanation of MD_CALL_PROTOTYPES.

	* builtins.c, calls.c: Change all instances of gen_call_* or
	gen_sibcall_* to GEN_CALL_* and GEN_SIBCALL_*.
	* calls.c (struct_value_size_rtx): Separate definition from
	initialization to avoid unused variable warning.

	* genflags.c (gen_macro): New function.
	(gen_proto): Call it for gen_call_* and gen_sibcall_*.
	(gen_nonproto): Delete.
	(gen_insn): Put all insns on the same obstack.
	(main): Generate prototypes for everything unconditionally.

===================================================================
Index: Makefile.in
--- Makefile.in	2000/05/20 11:48:03	1.450
+++ Makefile.in	2000/05/20 19:49:36
@@ -76,7 +76,8 @@ XCFLAGS =
 TCFLAGS =
 CFLAGS = -g @stage1_warn_cflags@
 BOOT_CFLAGS = -O2 $(CFLAGS)
-WARN_CFLAGS = -W -Wall -Wtraditional -pedantic -Wno-long-long -Wwrite-strings
+WARN_CFLAGS = -W -Wall -Wtraditional -pedantic -Wno-long-long \
+	      -Wwrite-strings -Wstrict-prototypes -Wmissing-prototypes
 LOOSE_CFLAGS = `echo $(CFLAGS)|sed -e 's/-pedantic//g' -e 's/-Wtraditional//g'`
 # These exists to be overridden by the x-* and t-* files, respectively.
 X_CFLAGS =
===================================================================
Index: builtins.c
--- builtins.c	2000/04/20 10:54:51	1.48
+++ builtins.c	2000/05/20 19:49:37
@@ -981,7 +981,7 @@ expand_builtin_apply (function, argument
 	    valreg = gen_rtx_REG (mode, regno);
 	  }
 
-      emit_call_insn (gen_call_value (valreg,
+      emit_call_insn (GEN_CALL_VALUE (valreg,
 				      gen_rtx_MEM (FUNCTION_MODE, function),
 				      const0_rtx, NULL_RTX, const0_rtx));
 
===================================================================
Index: calls.c
--- calls.c	2000/05/15 19:12:54	1.135
+++ calls.c	2000/05/20 19:49:38
@@ -449,12 +449,13 @@ emit_call_1 (funexp, fndecl, funtype, st
      int ecf_flags;
 {
   rtx rounded_stack_size_rtx = GEN_INT (rounded_stack_size);
-#if defined (HAVE_call) && defined (HAVE_call_value)
-  rtx struct_value_size_rtx = GEN_INT (struct_value_size);
-#endif
   rtx call_insn;
   int already_popped = 0;
   HOST_WIDE_INT n_popped = RETURN_POPS_ARGS (fndecl, funtype, stack_size);
+#if defined (HAVE_call) && defined (HAVE_call_value)
+  rtx struct_value_size_rtx;
+  struct_value_size_rtx = GEN_INT (struct_value_size);
+#endif
 
   /* Ensure address is valid.  SYMBOL_REF is already valid, so no need,
      and we don't want to load it into a register as an optimization,
@@ -475,12 +476,12 @@ emit_call_1 (funexp, fndecl, funtype, st
 	 if possible, for the sake of frame pointer elimination.  */
 
       if (valreg)
-	pat = gen_sibcall_value_pop (valreg,
+	pat = GEN_SIBCALL_VALUE_POP (valreg,
 				     gen_rtx_MEM (FUNCTION_MODE, funexp),
 				     rounded_stack_size_rtx, next_arg_reg,
 				     n_pop);
       else
-	pat = gen_sibcall_pop (gen_rtx_MEM (FUNCTION_MODE, funexp),
+	pat = GEN_SIBCALL_POP (gen_rtx_MEM (FUNCTION_MODE, funexp),
 			       rounded_stack_size_rtx, next_arg_reg, n_pop);
 
       emit_call_insn (pat);
@@ -508,11 +509,11 @@ emit_call_1 (funexp, fndecl, funtype, st
 	 if possible, for the sake of frame pointer elimination.  */
 
       if (valreg)
-	pat = gen_call_value_pop (valreg,
+	pat = GEN_CALL_VALUE_POP (valreg,
 				  gen_rtx_MEM (FUNCTION_MODE, funexp),
 				  rounded_stack_size_rtx, next_arg_reg, n_pop);
       else
-	pat = gen_call_pop (gen_rtx_MEM (FUNCTION_MODE, funexp),
+	pat = GEN_CALL_POP (gen_rtx_MEM (FUNCTION_MODE, funexp),
 			    rounded_stack_size_rtx, next_arg_reg, n_pop);
 
       emit_call_insn (pat);
@@ -526,12 +527,12 @@ emit_call_1 (funexp, fndecl, funtype, st
       && HAVE_sibcall && HAVE_sibcall_value)
     {
       if (valreg)
-	emit_call_insn (gen_sibcall_value (valreg,
+	emit_call_insn (GEN_SIBCALL_VALUE (valreg,
 					   gen_rtx_MEM (FUNCTION_MODE, funexp),
 					   rounded_stack_size_rtx,
 					   next_arg_reg, NULL_RTX));
       else
-	emit_call_insn (gen_sibcall (gen_rtx_MEM (FUNCTION_MODE, funexp),
+	emit_call_insn (GEN_SIBCALL (gen_rtx_MEM (FUNCTION_MODE, funexp),
 				     rounded_stack_size_rtx, next_arg_reg,
 				     struct_value_size_rtx));
     }
@@ -542,12 +543,12 @@ emit_call_1 (funexp, fndecl, funtype, st
   if (HAVE_call && HAVE_call_value)
     {
       if (valreg)
-	emit_call_insn (gen_call_value (valreg,
+	emit_call_insn (GEN_CALL_VALUE (valreg,
 					gen_rtx_MEM (FUNCTION_MODE, funexp),
 					rounded_stack_size_rtx, next_arg_reg,
 					NULL_RTX));
       else
-	emit_call_insn (gen_call (gen_rtx_MEM (FUNCTION_MODE, funexp),
+	emit_call_insn (GEN_CALL (gen_rtx_MEM (FUNCTION_MODE, funexp),
 				  rounded_stack_size_rtx, next_arg_reg,
 				  struct_value_size_rtx));
     }
===================================================================
Index: gcc.texi
--- gcc.texi	2000/05/19 04:43:18	1.48
+++ gcc.texi	2000/05/20 19:49:40
@@ -3911,15 +3911,6 @@ GCC.  If @samp{USE_PROTOTYPES} is not de
 determined automatically whether your compiler supports
 prototypes by checking if @samp{__STDC__} is defined.
 
-@findex MD_CALL_PROTOTYPES
-@item MD_CALL_PROTOTYPES
-Define this if you wish to generate prototypes for the @code{gen_call}
-or @code{gen_call_value} functions generated from the machine
-description file.  If @samp{USE_PROTOTYPES} is defined to be 0, or the
-host compiler does not support prototypes, this macro has no effect.  As
-soon as all of the machine descriptions are modified to have the
-appropriate number of arguments, this macro will be removed.
-
 @findex PATH_SEPARATOR
 @item PATH_SEPARATOR
 Define this macro to be a C character constant representing the
===================================================================
Index: genflags.c
--- genflags.c	2000/05/18 22:05:14	1.34
+++ genflags.c	2000/05/20 19:49:40
@@ -33,8 +33,8 @@ Boston, MA 02111-1307, USA.  */
 #define obstack_chunk_alloc xmalloc
 #define obstack_chunk_free free
 
-/* Obstacks to remember normal, and call insns.  */
-static struct obstack call_obstack, normal_obstack;
+/* Obstack to remember insns with.  */
+static struct obstack obstack;
 
 /* Max size of names encountered.  */
 static int max_id_len;
@@ -45,7 +45,7 @@ static int max_opno;
 static void max_operand_1	PARAMS ((rtx));
 static int num_operands		PARAMS ((rtx));
 static void gen_proto		PARAMS ((rtx));
-static void gen_nonproto	PARAMS ((rtx));
+static void gen_macro		PARAMS ((const char *, int, int));
 static void gen_insn		PARAMS ((rtx));
 
 /* Count the number of match_operand's found.  */
@@ -98,6 +98,36 @@ num_operands (insn)
   return max_opno + 1;
 }
 
+/* Print out a wrapper macro for a function which corrects the number
+   of arguments it takes.  Any missing arguments are assumed to be at
+   the end.  */
+static void
+gen_macro (name, real, expect)
+     const char *name;
+     int real, expect;
+{
+  int i;
+
+  if (real > expect)
+    abort ();
+  if (real == 0)
+    abort ();
+
+  /* #define GEN_CALL(A, B, C, D) gen_call((A), (B)) */
+  fputs ("#define GEN_", stdout);
+  for (i = 0; name[i]; i++)
+    putchar (TOUPPER (name[i]));
+
+  putchar('(');
+  for (i = 0; i < expect - 1; i++)
+    printf ("%c, ", i + 'A');
+  printf ("%c) gen_%s (", i + 'A', name);
+
+  for (i = 0; i < real - 1; i++)
+    printf ("(%c), ", i + 'A');
+  printf ("(%c))\n", i + 'A');
+}
+
 /* Print out prototype information for a function.  */
 
 static void
@@ -105,7 +135,28 @@ gen_proto (insn)
      rtx insn;
 {
   int num = num_operands (insn);
-  printf ("extern rtx gen_%-*s PARAMS ((", max_id_len, XSTR (insn, 0));
+  const char *name = XSTR (insn, 0);
+
+  /* Many md files don't refer to the last two operands passed to the
+     call patterns.  This means their generator functions will be two
+     arguments too short.  Instead of changing every md file to touch
+     those operands, we wrap the prototypes in macros that take the
+     correct number of arguments.  */
+  if (name[0] == 'c' || name[0] == 's')
+    {
+      if (!strcmp (name, "call")
+	  || !strcmp (name, "call_pop")
+	  || !strcmp (name, "sibcall")
+	  || !strcmp (name, "sibcall_pop"))
+	gen_macro (name, num, 4);
+      else if (!strcmp (name, "call_value")
+	       || !strcmp (name, "call_value_pop")
+	       || !strcmp (name, "sibcall_value")
+	       || !strcmp (name, "sibcall_value_pop"))
+	gen_macro (name, num, 5);
+    }
+
+  printf ("extern rtx gen_%-*s PARAMS ((", max_id_len, name);
 
   if (num == 0)
     printf ("void");
@@ -118,15 +169,7 @@ gen_proto (insn)
     }
 
   printf ("));\n");
-}
-
-/* Print out a function declaration without a prototype.  */
 
-static void
-gen_nonproto (insn)
-     rtx insn;
-{
-  printf ("extern rtx gen_%s ();\n", XSTR (insn, 0));
 }
 
 static void
@@ -135,7 +178,6 @@ gen_insn (insn)
 {
   const char *name = XSTR (insn, 0);
   const char *p;
-  struct obstack *obstack_ptr;
   int len;
 
   /* Don't mention instructions whose names are the null string
@@ -167,24 +209,7 @@ gen_insn (insn)
       printf (")\n");
     }
 
-  /* Save the current insn, so that we can later put out appropriate
-     prototypes.  At present, most md files have the wrong number of
-     arguments for the call insns (call, call_value, call_pop,
-     call_value_pop) ignoring the extra arguments that are passed for
-     some machines, so by default, turn off the prototype.  */
-
-  obstack_ptr = ((name[0] == 'c' || name[0] == 's')
-		 && (!strcmp (name, "call")
-		     || !strcmp (name, "call_value")
-		     || !strcmp (name, "call_pop")
-		     || !strcmp (name, "call_value_pop")
-		     || !strcmp (name, "sibcall")
-		     || !strcmp (name, "sibcall_value")
-		     || !strcmp (name, "sibcall_pop")
-		     || !strcmp (name, "sibcall_value_pop")))
-    ? &call_obstack : &normal_obstack;
-
-  obstack_grow (obstack_ptr, &insn, sizeof (rtx));
+  obstack_grow (&obstack, &insn, sizeof (rtx));
 }
 
 extern int main PARAMS ((int, char **));
@@ -196,13 +221,11 @@ main (argc, argv)
 {
   rtx desc;
   rtx dummy;
-  rtx *call_insns;
-  rtx *normal_insns;
+  rtx *insns;
   rtx *insn_ptr;
 
   progname = "genflags";
-  obstack_init (&call_obstack);
-  obstack_init (&normal_obstack);
+  obstack_init (&obstack);
 
   if (argc <= 1)
     fatal ("No input file name.");
@@ -228,24 +251,11 @@ from the machine description file `md'. 
 
   /* Print out the prototypes now.  */
   dummy = (rtx) 0;
-  obstack_grow (&call_obstack, &dummy, sizeof (rtx));
-  call_insns = (rtx *) obstack_finish (&call_obstack);
-
-  obstack_grow (&normal_obstack, &dummy, sizeof (rtx));
-  normal_insns = (rtx *) obstack_finish (&normal_obstack);
+  obstack_grow (&obstack, &dummy, sizeof (rtx));
+  insns = (rtx *) obstack_finish (&obstack);
 
-  for (insn_ptr = normal_insns; *insn_ptr; insn_ptr++)
+  for (insn_ptr = insns; *insn_ptr; insn_ptr++)
     gen_proto (*insn_ptr);
-
-  printf ("\n#ifdef MD_CALL_PROTOTYPES\n");
-  for (insn_ptr = call_insns; *insn_ptr; insn_ptr++)
-    gen_proto (*insn_ptr);
-
-  printf ("\n#else /* !MD_CALL_PROTOTYPES */\n");
-  for (insn_ptr = call_insns; *insn_ptr; insn_ptr++)
-    gen_nonproto (*insn_ptr);
-
-  printf ("#endif /* !MD_CALL_PROTOTYPES */\n");
 
   fflush (stdout);
   return (ferror (stdout) != 0 ? FATAL_EXIT_CODE : SUCCESS_EXIT_CODE);