* stdlib/Makefile (mpn-stuff): New target.

	(copy-mpn): Use it.

	* Code copied from GMP updated to 1.937 version.
	* stdlib/strtod.c (HAVE_ALLOCA): Define this for gmp headers.

4 files changed, 535 insertions, 27 deletions

diff --git a/sysdeps/m88k/m88110/add_n.S b/sysdeps/m88k/m88110/add_n.S
new file mode 100644
index 0000000..ab20630
--- /dev/null
+++ b/sysdeps/m88k/m88110/add_n.S
@@ -0,0 +1,199 @@
+; mc88110 __mpn_add_n -- Add two limb vectors of the same length > 0 and store
+; sum in a third limb vector.
+
+; Copyright (C) 1995, 1996 Free Software Foundation, Inc.
+
+; This file is part of the GNU MP Library.
+
+; The GNU MP Library is free software; you can redistribute it and/or modify
+; it under the terms of the GNU Library General Public License as published by
+; the Free Software Foundation; either version 2 of the License, or (at your
+; option) any later version.
+
+; The GNU MP Library 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 Library General Public
+; License for more details.
+
+; You should have received a copy of the GNU Library General Public License
+; along with the GNU MP Library; see the file COPYING.LIB.  If not, write to
+; the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+
+; INPUT PARAMETERS
+#define res_ptr	r2
+#define s1_ptr	r3
+#define s2_ptr	r4
+#define size	r5
+
+#include "sysdep.h"
+
+	text
+	align	16
+	global	C_SYMBOL_NAME(__mpn_add_n)
+C_SYMBOL_NAME(__mpn_add_n):
+	addu.co	 r0,r0,r0		; clear cy flag
+	xor	 r12,s2_ptr,res_ptr
+	bb1	 2,r12,L1
+; **  V1a  **
+L0:	bb0	 2,res_ptr,L_v1		; branch if res_ptr is aligned?
+/* Add least significant limb separately to align res_ptr and s2_ptr */
+	ld	 r10,s1_ptr,0
+	addu	 s1_ptr,s1_ptr,4
+	ld	 r8,s2_ptr,0
+	addu	 s2_ptr,s2_ptr,4
+	subu	 size,size,1
+	addu.co	 r6,r10,r8
+	st	 r6,res_ptr,0
+	addu	 res_ptr,res_ptr,4
+L_v1:	cmp	 r12,size,2
+	bb1	 lt,r12,Lend2
+
+	ld	 r10,s1_ptr,0
+	ld	 r12,s1_ptr,4
+	ld.d	 r8,s2_ptr,0
+	subu	 size,size,10
+	bcnd	 lt0,size,Lfin1
+/* Add blocks of 8 limbs until less than 8 limbs remain */
+	align	 8
+Loop1:	subu	 size,size,8
+	addu.cio r6,r10,r8
+	ld	 r10,s1_ptr,8
+	addu.cio r7,r12,r9
+	ld	 r12,s1_ptr,12
+	ld.d	 r8,s2_ptr,8
+	st.d	 r6,res_ptr,0
+	addu.cio r6,r10,r8
+	ld	 r10,s1_ptr,16
+	addu.cio r7,r12,r9
+	ld	 r12,s1_ptr,20
+	ld.d	 r8,s2_ptr,16
+	st.d	 r6,res_ptr,8
+	addu.cio r6,r10,r8
+	ld	 r10,s1_ptr,24
+	addu.cio r7,r12,r9
+	ld	 r12,s1_ptr,28
+	ld.d	 r8,s2_ptr,24
+	st.d	 r6,res_ptr,16
+	addu.cio r6,r10,r8
+	ld	 r10,s1_ptr,32
+	addu.cio r7,r12,r9
+	ld	 r12,s1_ptr,36
+	addu	 s1_ptr,s1_ptr,32
+	ld.d	 r8,s2_ptr,32
+	addu	 s2_ptr,s2_ptr,32
+	st.d	 r6,res_ptr,24
+	addu	 res_ptr,res_ptr,32
+	bcnd	 ge0,size,Loop1
+
+Lfin1:	addu	 size,size,8-2
+	bcnd	 lt0,size,Lend1
+/* Add blocks of 2 limbs until less than 2 limbs remain */
+Loope1:	addu.cio r6,r10,r8
+	ld	 r10,s1_ptr,8
+	addu.cio r7,r12,r9
+	ld	 r12,s1_ptr,12
+	ld.d	 r8,s2_ptr,8
+	st.d	 r6,res_ptr,0
+	subu	 size,size,2
+	addu	 s1_ptr,s1_ptr,8
+	addu	 s2_ptr,s2_ptr,8
+	addu	 res_ptr,res_ptr,8
+	bcnd	 ge0,size,Loope1
+Lend1:	addu.cio r6,r10,r8
+	addu.cio r7,r12,r9
+	st.d	 r6,res_ptr,0
+
+	bb0	 0,size,Lret1
+/* Add last limb */
+	ld	 r10,s1_ptr,8
+	ld	 r8,s2_ptr,8
+	addu.cio r6,r10,r8
+	st	 r6,res_ptr,8
+
+Lret1:	jmp.n	 r1
+	addu.ci	 r2,r0,r0		; return carry-out from most sign. limb
+
+L1:	xor	 r12,s1_ptr,res_ptr
+	bb1	 2,r12,L2
+; **  V1b  **
+	or	 r12,r0,s2_ptr
+	or	 s2_ptr,r0,s1_ptr
+	or	 s1_ptr,r0,r12
+	br	 L0
+
+; **  V2  **
+/* If we come here, the alignment of s1_ptr and res_ptr as well as the
+   alignment of s2_ptr and res_ptr differ.  Since there are only two ways
+   things can be aligned (that we care about) we now know that the alignment
+   of s1_ptr and s2_ptr are the same.  */
+
+L2:	cmp	 r12,size,1
+	bb1	 eq,r12,Ljone
+	bb0	 2,s1_ptr,L_v2		; branch if s1_ptr is aligned
+/* Add least significant limb separately to align res_ptr and s2_ptr */
+	ld	 r10,s1_ptr,0
+	addu	 s1_ptr,s1_ptr,4
+	ld	 r8,s2_ptr,0
+	addu	 s2_ptr,s2_ptr,4
+	subu	 size,size,1
+	addu.co	 r6,r10,r8
+	st	 r6,res_ptr,0
+	addu	 res_ptr,res_ptr,4
+
+L_v2:	subu	 size,size,8
+	bcnd	 lt0,size,Lfin2
+/* Add blocks of 8 limbs until less than 8 limbs remain */
+	align	 8
+Loop2:	subu	 size,size,8
+	ld.d	 r8,s1_ptr,0
+	ld.d	 r6,s2_ptr,0
+	addu.cio r8,r8,r6
+	st	 r8,res_ptr,0
+	addu.cio r9,r9,r7
+	st	 r9,res_ptr,4
+	ld.d	 r8,s1_ptr,8
+	ld.d	 r6,s2_ptr,8
+	addu.cio r8,r8,r6
+	st	 r8,res_ptr,8
+	addu.cio r9,r9,r7
+	st	 r9,res_ptr,12
+	ld.d	 r8,s1_ptr,16
+	ld.d	 r6,s2_ptr,16
+	addu.cio r8,r8,r6
+	st	 r8,res_ptr,16
+	addu.cio r9,r9,r7
+	st	 r9,res_ptr,20
+	ld.d	 r8,s1_ptr,24
+	ld.d	 r6,s2_ptr,24
+	addu.cio r8,r8,r6
+	st	 r8,res_ptr,24
+	addu.cio r9,r9,r7
+	st	 r9,res_ptr,28
+	addu	 s1_ptr,s1_ptr,32
+	addu	 s2_ptr,s2_ptr,32
+	addu	 res_ptr,res_ptr,32
+	bcnd	 ge0,size,Loop2
+
+Lfin2:	addu	 size,size,8-2
+	bcnd	 lt0,size,Lend2
+Loope2:	ld.d	 r8,s1_ptr,0
+	ld.d	 r6,s2_ptr,0
+	addu.cio r8,r8,r6
+	st	 r8,res_ptr,0
+	addu.cio r9,r9,r7
+	st	 r9,res_ptr,4
+	subu	 size,size,2
+	addu	 s1_ptr,s1_ptr,8
+	addu	 s2_ptr,s2_ptr,8
+	addu	 res_ptr,res_ptr,8
+	bcnd	 ge0,size,Loope2
+Lend2:	bb0	 0,size,Lret2
+/* Add last limb */
+Ljone:	ld	 r10,s1_ptr,0
+	ld	 r8,s2_ptr,0
+	addu.cio r6,r10,r8
+	st	 r6,res_ptr,0
+
+Lret2:	jmp.n	 r1
+	addu.ci	 r2,r0,r0		; return carry-out from most sign. limb
diff --git a/sysdeps/m88k/m88110/addmul_1.s b/sysdeps/m88k/m88110/addmul_1.s
new file mode 100644
index 0000000..1a4dfa1
--- /dev/null
+++ b/sysdeps/m88k/m88110/addmul_1.s
@@ -0,0 +1,60 @@
+; mc88110 __mpn_addmul_1 -- Multiply a limb vector with a single limb and
+; store the product in a second limb vector.
+
+; Copyright (C) 1996 Free Software Foundation, Inc.
+
+; This file is part of the GNU MP Library.
+
+; The GNU MP Library is free software; you can redistribute it and/or modify
+; it under the terms of the GNU Library General Public License as published by
+; the Free Software Foundation; either version 2 of the License, or (at your
+; option) any later version.
+
+; The GNU MP Library 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 Library General Public
+; License for more details.
+
+; You should have received a copy of the GNU Library General Public License
+; along with the GNU MP Library; see the file COPYING.LIB.  If not, write to
+; the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+
+; INPUT PARAMETERS
+; res_ptr	r2
+; s1_ptr	r3
+; size		r4
+; s2_limb	r5
+
+	text
+	align	16
+	global	___mpn_addmul_1
+___mpn_addmul_1:
+	lda	 r3,r3[r4]
+	lda	 r8,r2[r4]		; RES_PTR in r8 since r2 is retval
+	subu	 r4,r0,r4
+	addu.co	 r2,r0,r0		; r2 = cy = 0
+
+	ld	 r6,r3[r4]
+	addu	 r4,r4,1
+	subu	 r8,r8,4
+	bcnd.n	 eq0,r4,Lend
+	 mulu.d	 r10,r6,r5
+
+Loop:	ld	 r7,r8[r4]
+	ld	 r6,r3[r4]
+	addu.cio r9,r11,r2
+	addu.ci	 r2,r10,r0
+	addu.co	 r9,r9,r7
+	st	 r9,r8[r4]
+	addu	 r4,r4,1
+	mulu.d	 r10,r6,r5
+	bcnd	 ne0,r4,Loop
+
+Lend:	ld	 r7,r8,0
+	addu.cio r9,r11,r2
+	addu.ci	 r2,r10,r0
+	addu.co	 r9,r9,r7
+	st	 r9,r8,0
+	jmp.n	 r1
+	 addu.ci r2,r2,r0
diff --git a/sysdeps/m88k/m88110/mul_1.s b/sysdeps/m88k/m88110/mul_1.s
index 08c3ca0..b1352ce 100644
--- a/sysdeps/m88k/m88110/mul_1.s
+++ b/sysdeps/m88k/m88110/mul_1.s
@@ -1,7 +1,7 @@
 ; mc88110 __mpn_mul_1 -- Multiply a limb vector with a single limb and
 ; store the product in a second limb vector.
 
-; Copyright (C) 1992, 1994 Free Software Foundation, Inc.
+; Copyright (C) 1992, 1994, 1995 Free Software Foundation, Inc.
 
 ; This file is part of the GNU MP Library.
 
@@ -56,29 +56,3 @@ Lend:	addu.cio r9,r11,r2
 	st	 r9,r8,4
 	jmp.n	 r1
 	 addu.ci r2,r10,r0
-
-; This is the Right Way to do this on '110.  4 cycles / 64-bit limb.
-;	ld.d	r10,
-;	mulu.d
-;	addu.cio
-;	addu.cio
-;	st.d
-;	mulu.d	,r11,r5
-;	ld.d	r12,
-;	mulu.d	,r10,r5
-;	addu.cio
-;	addu.cio
-;	st.d
-;	mulu.d
-;	ld.d	r10,
-;	mulu.d
-;	addu.cio
-;	addu.cio
-;	st.d
-;	mulu.d
-;	ld.d	r10,
-;	mulu.d
-;	addu.cio
-;	addu.cio
-;	st.d
-;	mulu.d
diff --git a/sysdeps/m88k/m88110/sub_n.S b/sysdeps/m88k/m88110/sub_n.S
new file mode 100644
index 0000000..74ee0ae
--- /dev/null
+++ b/sysdeps/m88k/m88110/sub_n.S
@@ -0,0 +1,275 @@
+; mc88110 __mpn_sub_n -- Subtract two limb vectors of the same length > 0 and
+; store difference in a third limb vector.
+
+; Copyright (C) 1995, 1996 Free Software Foundation, Inc.
+
+; This file is part of the GNU MP Library.
+
+; The GNU MP Library is free software; you can redistribute it and/or modify
+; it under the terms of the GNU Library General Public License as published by
+; the Free Software Foundation; either version 2 of the License, or (at your
+; option) any later version.
+
+; The GNU MP Library 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 Library General Public
+; License for more details.
+
+; You should have received a copy of the GNU Library General Public License
+; along with the GNU MP Library; see the file COPYING.LIB.  If not, write to
+; the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+
+; INPUT PARAMETERS
+#define res_ptr	r2
+#define s1_ptr	r3
+#define s2_ptr	r4
+#define size	r5
+
+#include "sysdep.h"
+
+	text
+	align	16
+	global	C_SYMBOL_NAME(__mpn_sub_n)
+C_SYMBOL_NAME(__mpn_sub_n):
+	subu.co	 r0,r0,r0		; set cy flag
+	xor	 r12,s2_ptr,res_ptr
+	bb1	 2,r12,L1
+; **  V1a  **
+L0:	bb0	 2,res_ptr,L_v1		; branch if res_ptr is aligned
+/* Add least significant limb separately to align res_ptr and s2_ptr */
+	ld	 r10,s1_ptr,0
+	addu	 s1_ptr,s1_ptr,4
+	ld	 r8,s2_ptr,0
+	addu	 s2_ptr,s2_ptr,4
+	subu	 size,size,1
+	subu.co	 r6,r10,r8
+	st	 r6,res_ptr,0
+	addu	 res_ptr,res_ptr,4
+L_v1:	cmp	 r12,size,2
+	bb1	 lt,r12,Lend2
+
+	ld	 r10,s1_ptr,0
+	ld	 r12,s1_ptr,4
+	ld.d	 r8,s2_ptr,0
+	subu	 size,size,10
+	bcnd	 lt0,size,Lfin1
+/* Add blocks of 8 limbs until less than 8 limbs remain */
+	align	 8
+Loop1:	subu	 size,size,8
+	subu.cio r6,r10,r8
+	ld	 r10,s1_ptr,8
+	subu.cio r7,r12,r9
+	ld	 r12,s1_ptr,12
+	ld.d	 r8,s2_ptr,8
+	st.d	 r6,res_ptr,0
+	subu.cio r6,r10,r8
+	ld	 r10,s1_ptr,16
+	subu.cio r7,r12,r9
+	ld	 r12,s1_ptr,20
+	ld.d	 r8,s2_ptr,16
+	st.d	 r6,res_ptr,8
+	subu.cio r6,r10,r8
+	ld	 r10,s1_ptr,24
+	subu.cio r7,r12,r9
+	ld	 r12,s1_ptr,28
+	ld.d	 r8,s2_ptr,24
+	st.d	 r6,res_ptr,16
+	subu.cio r6,r10,r8
+	ld	 r10,s1_ptr,32
+	subu.cio r7,r12,r9
+	ld	 r12,s1_ptr,36
+	addu	 s1_ptr,s1_ptr,32
+	ld.d	 r8,s2_ptr,32
+	addu	 s2_ptr,s2_ptr,32
+	st.d	 r6,res_ptr,24
+	addu	 res_ptr,res_ptr,32
+	bcnd	 ge0,size,Loop1
+
+Lfin1:	addu	 size,size,8-2
+	bcnd	 lt0,size,Lend1
+/* Add blocks of 2 limbs until less than 2 limbs remain */
+Loope1:	subu.cio r6,r10,r8
+	ld	 r10,s1_ptr,8
+	subu.cio r7,r12,r9
+	ld	 r12,s1_ptr,12
+	ld.d	 r8,s2_ptr,8
+	st.d	 r6,res_ptr,0
+	subu	 size,size,2
+	addu	 s1_ptr,s1_ptr,8
+	addu	 s2_ptr,s2_ptr,8
+	addu	 res_ptr,res_ptr,8
+	bcnd	 ge0,size,Loope1
+Lend1:	subu.cio r6,r10,r8
+	subu.cio r7,r12,r9
+	st.d	 r6,res_ptr,0
+
+	bb0	 0,size,Lret1
+/* Add last limb */
+	ld	 r10,s1_ptr,8
+	ld	 r8,s2_ptr,8
+	subu.cio r6,r10,r8
+	st	 r6,res_ptr,8
+
+Lret1:	addu.ci r2,r0,r0		; return carry-out from most sign. limb
+	jmp.n	 r1
+	 xor	r2,r2,1
+
+L1:	xor	 r12,s1_ptr,res_ptr
+	bb1	 2,r12,L2
+; **  V1b  **
+	bb0	 2,res_ptr,L_v1b	; branch if res_ptr is aligned
+/* Add least significant limb separately to align res_ptr and s1_ptr */
+	ld	 r10,s2_ptr,0
+	addu	 s2_ptr,s2_ptr,4
+	ld	 r8,s1_ptr,0
+	addu	 s1_ptr,s1_ptr,4
+	subu	 size,size,1
+	subu.co	 r6,r8,r10
+	st	 r6,res_ptr,0
+	addu	 res_ptr,res_ptr,4
+L_v1b:	cmp	 r12,size,2
+	bb1	 lt,r12,Lend2
+
+	ld	 r10,s2_ptr,0
+	ld	 r12,s2_ptr,4
+	ld.d	 r8,s1_ptr,0
+	subu	 size,size,10
+	bcnd	 lt0,size,Lfin1b
+/* Add blocks of 8 limbs until less than 8 limbs remain */
+	align	 8
+Loop1b:	subu	 size,size,8
+	subu.cio r6,r8,r10
+	ld	 r10,s2_ptr,8
+	subu.cio r7,r9,r12
+	ld	 r12,s2_ptr,12
+	ld.d	 r8,s1_ptr,8
+	st.d	 r6,res_ptr,0
+	subu.cio r6,r8,r10
+	ld	 r10,s2_ptr,16
+	subu.cio r7,r9,r12
+	ld	 r12,s2_ptr,20
+	ld.d	 r8,s1_ptr,16
+	st.d	 r6,res_ptr,8
+	subu.cio r6,r8,r10
+	ld	 r10,s2_ptr,24
+	subu.cio r7,r9,r12
+	ld	 r12,s2_ptr,28
+	ld.d	 r8,s1_ptr,24
+	st.d	 r6,res_ptr,16
+	subu.cio r6,r8,r10
+	ld	 r10,s2_ptr,32
+	subu.cio r7,r9,r12
+	ld	 r12,s2_ptr,36
+	addu	 s2_ptr,s2_ptr,32
+	ld.d	 r8,s1_ptr,32
+	addu	 s1_ptr,s1_ptr,32
+	st.d	 r6,res_ptr,24
+	addu	 res_ptr,res_ptr,32
+	bcnd	 ge0,size,Loop1b
+
+Lfin1b:	addu	 size,size,8-2
+	bcnd	 lt0,size,Lend1b
+/* Add blocks of 2 limbs until less than 2 limbs remain */
+Loope1b:subu.cio r6,r8,r10
+	ld	 r10,s2_ptr,8
+	subu.cio r7,r9,r12
+	ld	 r12,s2_ptr,12
+	ld.d	 r8,s1_ptr,8
+	st.d	 r6,res_ptr,0
+	subu	 size,size,2
+	addu	 s1_ptr,s1_ptr,8
+	addu	 s2_ptr,s2_ptr,8
+	addu	 res_ptr,res_ptr,8
+	bcnd	 ge0,size,Loope1b
+Lend1b:	subu.cio r6,r8,r10
+	subu.cio r7,r9,r12
+	st.d	 r6,res_ptr,0
+
+	bb0	 0,size,Lret1b
+/* Add last limb */
+	ld	 r10,s2_ptr,8
+	ld	 r8,s1_ptr,8
+	subu.cio r6,r8,r10
+	st	 r6,res_ptr,8
+
+Lret1b:	addu.ci r2,r0,r0		; return carry-out from most sign. limb
+	jmp.n	 r1
+	 xor	r2,r2,1
+
+; **  V2  **
+/* If we come here, the alignment of s1_ptr and res_ptr as well as the
+   alignment of s2_ptr and res_ptr differ.  Since there are only two ways
+   things can be aligned (that we care about) we now know that the alignment
+   of s1_ptr and s2_ptr are the same.  */
+
+L2:	cmp	 r12,size,1
+	bb1	 eq,r12,Ljone
+	bb0	 2,s1_ptr,L_v2		; branch if s1_ptr is aligned
+/* Add least significant limb separately to align res_ptr and s2_ptr */
+	ld	 r10,s1_ptr,0
+	addu	 s1_ptr,s1_ptr,4
+	ld	 r8,s2_ptr,0
+	addu	 s2_ptr,s2_ptr,4
+	subu	 size,size,1
+	subu.co	 r6,r10,r8
+	st	 r6,res_ptr,0
+	addu	 res_ptr,res_ptr,4
+
+L_v2:	subu	 size,size,8
+	bcnd	 lt0,size,Lfin2
+/* Add blocks of 8 limbs until less than 8 limbs remain */
+	align	 8
+Loop2:	subu	 size,size,8
+	ld.d	 r8,s1_ptr,0
+	ld.d	 r6,s2_ptr,0
+	subu.cio r8,r8,r6
+	st	 r8,res_ptr,0
+	subu.cio r9,r9,r7
+	st	 r9,res_ptr,4
+	ld.d	 r8,s1_ptr,8
+	ld.d	 r6,s2_ptr,8
+	subu.cio r8,r8,r6
+	st	 r8,res_ptr,8
+	subu.cio r9,r9,r7
+	st	 r9,res_ptr,12
+	ld.d	 r8,s1_ptr,16
+	ld.d	 r6,s2_ptr,16
+	subu.cio r8,r8,r6
+	st	 r8,res_ptr,16
+	subu.cio r9,r9,r7
+	st	 r9,res_ptr,20
+	ld.d	 r8,s1_ptr,24
+	ld.d	 r6,s2_ptr,24
+	subu.cio r8,r8,r6
+	st	 r8,res_ptr,24
+	subu.cio r9,r9,r7
+	st	 r9,res_ptr,28
+	addu	 s1_ptr,s1_ptr,32
+	addu	 s2_ptr,s2_ptr,32
+	addu	 res_ptr,res_ptr,32
+	bcnd	 ge0,size,Loop2
+
+Lfin2:	addu	 size,size,8-2
+	bcnd	 lt0,size,Lend2
+Loope2:	ld.d	 r8,s1_ptr,0
+	ld.d	 r6,s2_ptr,0
+	subu.cio r8,r8,r6
+	st	 r8,res_ptr,0
+	subu.cio r9,r9,r7
+	st	 r9,res_ptr,4
+	subu	 size,size,2
+	addu	 s1_ptr,s1_ptr,8
+	addu	 s2_ptr,s2_ptr,8
+	addu	 res_ptr,res_ptr,8
+	bcnd	 ge0,size,Loope2
+Lend2:	bb0	 0,size,Lret2
+/* Add last limb */
+Ljone:	ld	 r10,s1_ptr,0
+	ld	 r8,s2_ptr,0
+	subu.cio r6,r10,r8
+	st	 r6,res_ptr,0
+
+Lret2:	addu.ci r2,r0,r0		; return carry-out from most sign. limb
+	jmp.n	 r1
+	 xor	r2,r2,1