[PATCH] add udivhi3, umodhi3 functions to libgcc

[Paul Koning]

> On Oct 18, 2018, at 1:18 PM, Jeff Law <law@redhat.com> wrote:
> 
> On 10/17/18 5:48 PM, Paul Koning wrote:
>> This is a revision of a patch I proposed a while back, to add udivhi3 and umodhi3 functions to libgcc since some platforms (like pdp11) need it.  The code is adopted from that of udivsi3.
>> 
>> In earlier discussion it was pointed out that internal functions need to start with __.  The code I had copied does not do that, so I corrected mine and also changed the existing code to conform to the rules.
>> 
>> Ok for trunk?
>> 
>> 	paul
>> 
>> ChangeLog:
>> 
>> 2018-10-17  Paul Koning  <ni1d@arrl.net>
>> 
>> 	* udivmodsi4.c (__udivmodsi4): Rename to conform to coding
>> 	standard.
>> 	* udivmod.c: Update references to __udivmodsi4.
>> 	* udivhi3.c: New file.
>> 	* udivmodhi4.c: New file.
>> 	* config/pdp11/t-pdp11 (LIB2ADD): Add the new files.
> I think you need to fix divmod.c as well since it calls udivmodsi4.  OK
> with that fixed.
> 
> Jeff

Thanks.  Committed as shown below.

	paul

ChangeLog:

2018-10-18  Paul Koning  <ni1d@arrl.net>

	* udivmodsi4.c (__udivmodsi4): Rename to conform to coding
	standard.
	* divmod.c: Update references to __udivmodsi4.
	* udivmod.c: Ditto.
	* udivhi3.c: New file.
	* udivmodhi4.c: New file.
	* config/pdp11/t-pdp11 (LIB2ADD): Add the new files.

Index: config/pdp11/t-pdp11
===================================================================
--- config/pdp11/t-pdp11	(revision 265276)
+++ config/pdp11/t-pdp11	(working copy)
@@ -1,5 +1,7 @@
 LIB2ADD = $(srcdir)/udivmod.c \
 	  $(srcdir)/udivmodsi4.c \
+	  $(srcdir)/udivhi3.c \
+	  $(srcdir)/udivmodhi4.c \
 	  $(srcdir)/memcmp.c \
 	  $(srcdir)/memcpy.c \
 	  $(srcdir)/memmove.c \
Index: divmod.c
===================================================================
--- divmod.c	(revision 265276)
+++ divmod.c	(working copy)
@@ -21,7 +21,8 @@ a copy of the GCC Runtime Library Exception along
 see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
 <http://www.gnu.org/licenses/>.  */
 
-long udivmodsi4 ();
+extern unsigned long __udivmodsi4(unsigned long num, unsigned long den,
+								  int modwanted);
 
 long
 __divsi3 (long a, long b)
@@ -41,7 +42,7 @@ __divsi3 (long a, long b)
       neg = !neg;
     }
 
-  res = udivmodsi4 (a, b, 0);
+  res = __udivmodsi4 (a, b, 0);
 
   if (neg)
     res = -res;
@@ -64,7 +65,7 @@ __modsi3 (long a, long b)
   if (b < 0)
     b = -b;
 
-  res = udivmodsi4 (a, b, 1);
+  res = __udivmodsi4 (a, b, 1);
 
   if (neg)
     res = -res;
Index: udivhi3.c
===================================================================
--- udivhi3.c	(nonexistent)
+++ udivhi3.c	(working copy)
@@ -0,0 +1,38 @@
+/* Copyright (C) 2000-2018 Free Software Foundation, Inc.
+
+This file is part of GCC.
+
+GCC is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 3, or (at your option) any later
+version.
+
+GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+for more details.
+
+Under Section 7 of GPL version 3, you are granted additional
+permissions described in the GCC Runtime Library Exception, version
+3.1, as published by the Free Software Foundation.
+
+You should have received a copy of the GNU General Public License and
+a copy of the GCC Runtime Library Exception along with this program;
+see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
+<http://www.gnu.org/licenses/>.  */
+
+extern unsigned short __udivmodhi4(unsigned short num, unsigned short den,
+								   int modwanted);
+
+unsigned short
+__udivhi3 (unsigned short a, unsigned short b)
+{
+  return __udivmodhi4 (a, b, 0);
+}
+
+unsigned short
+__umodhi3 (unsigned short a, unsigned short b)
+{
+  return __udivmodhi4 (a, b, 1);
+}
+
Index: udivmod.c
===================================================================
--- udivmod.c	(revision 265276)
+++ udivmod.c	(working copy)
@@ -21,17 +21,18 @@ a copy of the GCC Runtime Library Exception along
 see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
 <http://www.gnu.org/licenses/>.  */
 
-long udivmodsi4 ();
+extern unsigned long __udivmodsi4(unsigned long num, unsigned long den,
+								  int modwanted);
 
 long
 __udivsi3 (long a, long b)
 {
-  return udivmodsi4 (a, b, 0);
+  return __udivmodsi4 (a, b, 0);
 }
 
 long
 __umodsi3 (long a, long b)
 {
-  return udivmodsi4 (a, b, 1);
+  return __udivmodsi4 (a, b, 1);
 }
 
Index: udivmodhi4.c
===================================================================
--- udivmodhi4.c	(nonexistent)
+++ udivmodhi4.c	(working copy)
@@ -0,0 +1,47 @@
+/* Copyright (C) 2000-2018 Free Software Foundation, Inc.
+
+This file is part of GCC.
+
+GCC is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 3, or (at your option) any later
+version.
+
+GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+for more details.
+
+Under Section 7 of GPL version 3, you are granted additional
+permissions described in the GCC Runtime Library Exception, version
+3.1, as published by the Free Software Foundation.
+
+You should have received a copy of the GNU General Public License and
+a copy of the GCC Runtime Library Exception along with this program;
+see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
+<http://www.gnu.org/licenses/>.  */
+
+unsigned short
+__udivmodhi4(unsigned short num, unsigned short den, int modwanted)
+{
+  unsigned short bit = 1;
+  unsigned short res = 0;
+
+  while (den < num && bit && !(den & (1L<<31)))
+    {
+      den <<=1;
+      bit <<=1;
+    }
+  while (bit)
+    {
+      if (num >= den)
+	{
+	  num -= den;
+	  res |= bit;
+	}
+      bit >>=1;
+      den >>=1;
+    }
+  if (modwanted) return num;
+  return res;
+}
Index: udivmodsi4.c
===================================================================
--- udivmodsi4.c	(revision 265276)
+++ udivmodsi4.c	(working copy)
@@ -22,7 +22,7 @@ see the files COPYING3 and COPYING.RUNTIME respect
 <http://www.gnu.org/licenses/>.  */
 
 unsigned long
-udivmodsi4(unsigned long num, unsigned long den, int modwanted)
+__udivmodsi4(unsigned long num, unsigned long den, int modwanted)
 {
   unsigned long bit = 1;
   unsigned long res = 0;