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diff --git a/rts/gmp/mpn/m88k/mul_1.s b/rts/gmp/mpn/m88k/mul_1.s
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+; mc88100 __gmpn_mul_1 -- Multiply a limb vector with a single limb and
+; store the product in a second limb vector.
+
+; Copyright (C) 1992, 1994, 1995, 2000 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 Lesser General Public License as published by
+; the Free Software Foundation; either version 2.1 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 Lesser General Public
+; License for more details.
+
+; You should have received a copy of the GNU Lesser General Public License
+; along with the GNU MP Library; see the file COPYING.LIB.  If not, write to
+; the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+; MA 02111-1307, USA.
+
+
+; INPUT PARAMETERS
+; res_ptr	r2
+; s1_ptr	r3
+; size		r4
+; s2_limb	r5
+
+; Common overhead is about 11 cycles/invocation.
+
+; The speed for S2_LIMB >= 0x10000 is approximately 21 cycles/limb.  (The
+; pipeline stalls 2 cycles due to WB contention.)
+
+; The speed for S2_LIMB < 0x10000 is approximately 16 cycles/limb.  (The
+; pipeline stalls 2 cycles due to WB contention and 1 cycle due to latency.)
+
+; To enhance speed:
+; 1. Unroll main loop 4-8 times.
+; 2. Schedule code to avoid WB contention.  It might be tempting to move the
+;    ld instruction in the loops down to save 2 cycles (less WB contention),
+;    but that looses because the ultimate value will be read from outside
+;    the allocated space.  But if we handle the ultimate multiplication in
+;    the tail, we can do this.
+; 3. Make the multiplication with less instructions.  I think the code for
+;    (S2_LIMB >= 0x10000) is not minimal.
+; With these techniques the (S2_LIMB >= 0x10000) case would run in 17 or
+; less cycles/limb; the (S2_LIMB < 0x10000) case would run in 11
+; cycles/limb.  (Assuming infinite unrolling.)
+
+	text
+	align	 16
+	global	 ___gmpn_mul_1
+___gmpn_mul_1:
+
+	; Make S1_PTR and RES_PTR point at the end of their blocks
+	; and negate SIZE.
+	lda	 r3,r3[r4]
+	lda	 r6,r2[r4]	; RES_PTR in r6 since r2 is retval
+	subu	 r4,r0,r4
+
+	addu.co	 r2,r0,r0	; r2 = cy = 0
+	ld	 r9,r3[r4]
+	mask	 r7,r5,0xffff	; r7 = lo(S2_LIMB)
+	extu	 r8,r5,16	; r8 = hi(S2_LIMB)
+	bcnd.n	 eq0,r8,Lsmall	; jump if (hi(S2_LIMB) == 0)
+	 subu	 r6,r6,4
+
+; General code for any value of S2_LIMB.
+
+	; Make a stack frame and save r25 and r26
+	subu	 r31,r31,16
+	st.d	 r25,r31,8
+
+	; Enter the loop in the middle
+	br.n	L1
+	addu	 r4,r4,1
+
+Loop:	ld	 r9,r3[r4]
+	st	 r26,r6[r4]
+; bcnd	ne0,r0,0		; bubble
+	addu	 r4,r4,1
+L1:	mul	 r26,r9,r5	; low word of product	mul_1	WB ld
+	mask	 r12,r9,0xffff	; r12 = lo(s1_limb)	mask_1
+	mul	 r11,r12,r7	; r11 =  prod_0		mul_2	WB mask_1
+	mul	 r10,r12,r8	; r10 = prod_1a		mul_3
+	extu	 r13,r9,16	; r13 = hi(s1_limb)	extu_1	WB mul_1
+	mul	 r12,r13,r7	; r12 = prod_1b		mul_4	WB extu_1
+	mul	 r25,r13,r8	; r25  = prod_2		mul_5	WB mul_2
+	extu	 r11,r11,16	; r11 = hi(prod_0)	extu_2	WB mul_3
+	addu	 r10,r10,r11	;			addu_1	WB extu_2
+; bcnd	ne0,r0,0		; bubble			WB addu_1
+	addu.co	 r10,r10,r12	;				WB mul_4
+	mask.u	 r10,r10,0xffff	; move the 16 most significant bits...
+	addu.ci	 r10,r10,r0	; ...to the low half of the word...
+	rot	 r10,r10,16	; ...and put carry in pos 16.
+	addu.co	 r26,r26,r2	; add old carry limb
+	bcnd.n	 ne0,r4,Loop
+	 addu.ci r2,r25,r10	; compute new carry limb
+
+	st	 r26,r6[r4]
+	ld.d	 r25,r31,8
+	jmp.n	 r1
+	 addu	 r31,r31,16
+
+; Fast code for S2_LIMB < 0x10000
+Lsmall:
+	; Enter the loop in the middle
+	br.n	SL1
+	addu	 r4,r4,1
+
+SLoop:	ld	 r9,r3[r4]	;
+	st	 r8,r6[r4]	;
+	addu	 r4,r4,1	;
+SL1:	mul	 r8,r9,r5	; low word of product
+	mask	 r12,r9,0xffff	; r12 = lo(s1_limb)
+	extu	 r13,r9,16	; r13 = hi(s1_limb)
+	mul	 r11,r12,r7	; r11 =  prod_0
+	mul	 r12,r13,r7	; r12 = prod_1b
+	addu.cio r8,r8,r2	; add old carry limb
+	extu	 r10,r11,16	; r11 = hi(prod_0)
+	addu	 r10,r10,r12	;
+	bcnd.n	 ne0,r4,SLoop
+	extu	 r2,r10,16	; r2 = new carry limb
+
+	jmp.n	 r1
+	st	 r8,r6[r4]