MIPS III/IV assembler module is reimplemented.

CHANGES

@@ -4,6 +4,9 @@
 
  Changes between 0.9.3a and 0.9.4
 
+  *) MIPS III/IV assembler module is reimplemented.
+     [Andy Polyakov]
+
   *) More DES library cleanups: remove references to srand/rand and
      delete an unused file.
      [Ulf Möller]

Configure

@@ -134,10 +134,10 @@ my %table=(
 "irix-gcc","gcc:-O2 -DTERMIOS -DB_ENDIAN::(unknown)::BN_LLONG MD2_CHAR RC4_INDEX RC4_CHAR DES_UNROLL DES_RISC2 DES_PTR BF_PTR:::",
 "irix-cc", "cc:-O2 -use_readonly_const -DTERMIOS -DB_ENDIAN::(unknown)::BN_LLONG DES_PTR DES_RISC2 DES_UNROLL BF_PTR:::",
 "irix-mips3-gcc","gcc:-mips3 -O2 -DTERMIOS -DB_ENDIAN::(unknown)::MD2_CHAR RC4_INDEX RC4_CHAR DES_UNROLL DES_RISC2 DES_PTR BF_PTR SIXTY_FOUR_BIT:::",
-"irix-mips3-cc", "cc:-n32 -mips3 -O2 -use_readonly_const -DTERMIOS -DB_ENDIAN::(unknown)::DES_PTR DES_RISC2 DES_UNROLL BF_PTR SIXTY_FOUR_BIT:::",
+"irix-mips3-cc", "cc:-O2 -use_readonly_const -DTERMIOS -DB_ENDIAN::(unknown)::DES_PTR DES_RISC2 DES_UNROLL BF_PTR SIXTY_FOUR_BIT:asm/mips3.o::",
 "debug-irix-cc", "cc:-w2 -g -DCRYPTO_MDEBUG -DTERMIOS -DB_ENDIAN::(unknown):::::",
 # This is the n64 mode build.
-"irix64-mips4-cc", "cc:-64 -mips4 -O2 -use_readonly_const -DTERMIOS -DB_ENDIAN::(unknown)::DES_RISC2 DES_UNROLL SIXTY_FOUR_BIT_LONG:::",
+"irix64-mips4-cc", "cc:-64 -O2 -use_readonly_const -DTERMIOS -DB_ENDIAN::(unknown)::DES_RISC2 DES_UNROLL SIXTY_FOUR_BIT_LONG:asm/mips3.o::",
 
 # HPUX 9.X config.
 # Don't use the bundled cc.  It is broken.  Use HP ANSI C if possible, or

crypto/bn/Makefile.ssl

@@ -20,6 +20,7 @@ BN_ASM=		bn_asm.o
 #BN_ASM=	bn86-elf.o
 
 CFLAGS= $(INCLUDES) $(CFLAG)
+ASFLAGS=$(CFLAGS)
 
 GENERAL=Makefile
 TEST=bntest.c exptest.c
@@ -110,7 +111,6 @@ asm/sparcv8plus-gcc.o: asm/sparcv8plus.S
 
 # MIPS 64 bit assember 
 asm/mips3.o: asm/mips3.s
-	/usr/bin/as -mips3 -O2 -o asm/mips3.o asm/mips3.s            
 
 # MIPS 32 bit assember
 asm/mips1.o: asm/mips1.s

crypto/bn/asm/mips3.s

+.rdata
+.asciiz "mips3.s, Version 1.0 (prerelease)"
+.asciiz	"MIPS III/IV ISA artwork by Andy Polyakov <appro@fy.chalmers.se>"
+
+/*
+ * ====================================================================
+ * Written by Andy Polyakov <appro@fy.chalmers.se> for the OpenSSL
+ * project.
+ *
+ * Rights for redistribution and usage in source and binary forms are
+ * granted according to the OpenSSL license. Warranty of any kind is
+ * disclaimed.
+ * ====================================================================
+ */
+
+/*
+ * This is my modest contributon to the OpenSSL project (see
+ * http://www.openssl.org/ for more information about it) and is
+ * a drop-in MIPS III/IV ISA replacement for crypto/bn/bn_asm.c
+ * module. For updates see http://fy.chalmers.se/~appro/hpe/.
+ *
+ * The module is designed to work with "new" IRIX ABI(5), namely
+ * N32 and N64. But it was tested only with MIPSpro 7.2.x assembler,
+ * i.e. depends on preprocessor options set up by MIPSspro 7.2.x
+ * driver. Another neat gadget offered by MIPSpro 7.2.x assembler is
+ * an peep-hole(?) optimization pass. This gave me the opportunity
+ * to make the code looking more regular as all those architecture
+ * dependent(!) instruction rescheduling details were left to the
+ * assembler. Cool, huh? Do note that I have no idea if GNU assembler
+ * does anything similar nor how GNU C will do with this module.
+ * Feedback on the matter is therefore very much appreciated:-)
+ *
+ * Performance improvement is astonishing! 'apps/openssl speed rsa dsa'
+ * exhibits 3-3.5-3.7 times improvement!
+ *
+ *					<appro@fy.chalmers.se>
+ */
+#include <asm.h>
+#include <regdef.h>
+
+#if _MIPS_ISA>=4
+#define	MOVNZ(cond,dst,src)	\
+	movn	dst,src,cond
+#else
+#define	MOVNZ(cond,dst,src)	\
+	.set	noreorder;	\
+	bnezl	cond,.+8;	\
+	move	dst,src;	\
+	.set	reorder
+#endif
+
+.text
+
+.set	noat
+.set	reorder
+
+#define	MINUS4	v1
+
+LEAF(bn_mul_add_words)
+	.align	5
+	.set	noreorder
+	bgtzl	a2,.L_bn_mul_add_words_proceed
+	ld	t0,0(a1)
+	jr	ra
+	move	v0,zero
+	.set	reorder
+
+.L_bn_mul_add_words_proceed:
+	li	MINUS4,-4
+	and	ta0,a2,MINUS4
+	move	v0,zero
+	beqz	ta0,.L_bn_mul_add_words_tail
+
+.L_bn_mul_add_words_loop:
+	dmultu	t0,a3
+	ld	t1,0(a0)
+	ld	t2,8(a1)
+	ld	t3,8(a0)
+	ld	ta0,16(a1)
+	ld	ta1,16(a0)
+	daddu	t1,v0
+	sltu	v0,t1,v0	/* All manuals say it "compares 32-bit
+				 * values", but it seems to work fine
+				 * even on 64-bit registers. */
+	mflo	AT
+	mfhi	t0
+	daddu	t1,AT
+	daddu	v0,t0
+	sltu	AT,t1,AT
+	sd	t1,0(a0)
+	daddu	v0,AT
+
+	dmultu	t2,a3
+	ld	ta2,24(a1)
+	ld	ta3,24(a0)
+	daddu	t3,v0
+	sltu	v0,t3,v0
+	mflo	AT
+	mfhi	t2
+	daddu	t3,AT
+	daddu	v0,t2
+	sltu	AT,t3,AT
+	sd	t3,8(a0)
+	daddu	v0,AT
+
+	dmultu	ta0,a3
+	subu	a2,4
+	PTR_ADD	a0,32
+	PTR_ADD	a1,32
+	daddu	ta1,v0
+	sltu	v0,ta1,v0
+	mflo	AT
+	mfhi	ta0
+	daddu	ta1,AT
+	daddu	v0,ta0
+	sltu	AT,ta1,AT
+	sd	ta1,-16(a0)
+	daddu	v0,AT
+
+
+	dmultu	ta2,a3
+	and	ta0,a2,MINUS4
+	daddu	ta3,v0
+	sltu	v0,ta3,v0
+	mflo	AT
+	mfhi	ta2
+	daddu	ta3,AT
+	daddu	v0,ta2
+	sltu	AT,ta3,AT
+	sd	ta3,-8(a0)
+	daddu	v0,AT
+	.set	noreorder
+	bgtzl	ta0,.L_bn_mul_add_words_loop
+	ld	t0,0(a1)
+
+	bnezl	a2,.L_bn_mul_add_words_tail
+	ld	t0,0(a1)
+	.set	reorder
+
+.L_bn_mul_add_words_return:
+	jr	ra
+
+.L_bn_mul_add_words_tail:
+	dmultu	t0,a3
+	ld	t1,0(a0)
+	subu	a2,1
+	daddu	t1,v0
+	sltu	v0,t1,v0
+	mflo	AT
+	mfhi	t0
+	daddu	t1,AT
+	daddu	v0,t0
+	sltu	AT,t1,AT
+	sd	t1,0(a0)
+	daddu	v0,AT
+	beqz	a2,.L_bn_mul_add_words_return
+
+	ld	t0,8(a1)
+	dmultu	t0,a3
+	ld	t1,8(a0)
+	subu	a2,1
+	daddu	t1,v0
+	sltu	v0,t1,v0
+	mflo	AT
+	mfhi	t0
+	daddu	t1,AT
+	daddu	v0,t0
+	sltu	AT,t1,AT
+	sd	t1,8(a0)
+	daddu	v0,AT
+	beqz	a2,.L_bn_mul_add_words_return
+
+	ld	t0,16(a1)
+	dmultu	t0,a3
+	ld	t1,16(a0)
+	daddu	t1,v0
+	sltu	v0,t1,v0
+	mflo	AT
+	mfhi	t0
+	daddu	t1,AT
+	daddu	v0,t0
+	sltu	AT,t1,AT
+	sd	t1,16(a0)
+	daddu	v0,AT
+	jr	ra
+END(bn_mul_add_words)
+
+LEAF(bn_mul_words)
+	.align	5
+	.set	noreorder
+	bgtzl	a2,.L_bn_mul_words_proceed
+	ld	t0,0(a1)
+	jr	ra
+	move	v0,zero
+	.set	reorder
+
+.L_bn_mul_words_proceed:
+	li	MINUS4,-4
+	and	ta0,a2,MINUS4
+	move	v0,zero
+	beqz	ta0,.L_bn_mul_words_tail
+
+.L_bn_mul_words_loop:
+	dmultu	t0,a3
+	ld	t2,8(a1)
+	ld	ta0,16(a1)
+	ld	ta2,24(a1)
+	mflo	AT
+	mfhi	t0
+	daddu	v0,AT
+	sltu	t1,v0,AT
+	sd	v0,0(a0)
+	daddu	v0,t1,t0
+
+	dmultu	t2,a3
+	subu	a2,4
+	PTR_ADD	a0,32
+	PTR_ADD	a1,32
+	mflo	AT
+	mfhi	t2
+	daddu	v0,AT
+	sltu	t3,v0,AT
+	sd	v0,-24(a0)
+	daddu	v0,t3,t2
+
+	dmultu	ta0,a3
+	mflo	AT
+	mfhi	ta0
+	daddu	v0,AT
+	sltu	ta1,v0,AT
+	sd	v0,-16(a0)
+	daddu	v0,ta1,ta0
+
+
+	dmultu	ta2,a3
+	and	ta0,a2,MINUS4
+	mflo	AT
+	mfhi	ta2
+	daddu	v0,AT
+	sltu	ta3,v0,AT
+	sd	v0,-8(a0)
+	daddu	v0,ta3,ta2
+	.set	noreorder
+	bgtzl	ta0,.L_bn_mul_words_loop
+	ld	t0,0(a1)
+
+	bnezl	a2,.L_bn_mul_words_tail
+	ld	t0,0(a1)
+	.set	reorder
+
+.L_bn_mul_words_return:
+	jr	ra
+
+.L_bn_mul_words_tail:
+	dmultu	t0,a3
+	subu	a2,1
+	mflo	AT
+	mfhi	t0
+	daddu	v0,AT
+	sltu	t1,v0,AT
+	sd	v0,0(a0)
+	daddu	v0,t1,t0
+	beqz	a2,.L_bn_mul_words_return
+
+	ld	t0,8(a1)
+	dmultu	t0,a3
+	subu	a2,1
+	mflo	AT
+	mfhi	t0
+	daddu	v0,AT
+	sltu	t1,v0,AT
+	sd	v0,8(a0)
+	daddu	v0,t1,t0
+	beqz	a2,.L_bn_mul_words_return
+
+	ld	t0,16(a1)
+	dmultu	t0,a3
+	mflo	AT
+	mfhi	t0
+	daddu	v0,AT
+	sltu	t1,v0,AT
+	sd	v0,16(a0)
+	daddu	v0,t1,t0
+	jr	ra
+END(bn_mul_words)
+
+LEAF(bn_sqr_words)
+	.align	5
+	.set	noreorder
+	bgtzl	a2,.L_bn_sqr_words_proceed
+	ld	t0,0(a1)
+	jr	ra
+	move	v0,zero
+	.set	reorder
+
+.L_bn_sqr_words_proceed:
+	li	MINUS4,-4
+	and	ta0,a2,MINUS4
+	move	v0,zero
+	beqz	ta0,.L_bn_sqr_words_tail
+
+.L_bn_sqr_words_loop:
+	dmultu	t0,t0
+	ld	t2,8(a1)
+	ld	ta0,16(a1)
+	ld	ta2,24(a1)
+	mflo	t1
+	mfhi	t0
+	sd	t1,0(a0)
+	sd	t0,8(a0)
+
+	dmultu	t2,t2
+	subu	a2,4
+	PTR_ADD	a0,64
+	PTR_ADD	a1,32
+	mflo	t3
+	mfhi	t2
+	sd	t3,-48(a0)
+	sd	t2,-40(a0)
+
+	dmultu	ta0,ta0
+	mflo	ta1
+	mfhi	ta0
+	sd	ta1,-32(a0)
+	sd	ta0,-24(a0)
+
+
+	dmultu	ta2,ta2
+	and	ta0,a2,MINUS4
+	mflo	ta3
+	mfhi	ta2
+	sd	ta3,-16(a0)
+	sd	ta2,-8(a0)
+
+	.set	noreorder
+	bgtzl	ta0,.L_bn_sqr_words_loop
+	ld	t0,0(a1)
+
+	bnezl	a2,.L_bn_sqr_words_tail
+	ld	t0,0(a1)
+	.set	reorder
+
+.L_bn_sqr_words_return:
+	move	v0,zero
+	jr	ra
+
+.L_bn_sqr_words_tail:
+	dmultu	t0,t0
+	subu	a2,1
+	mflo	t1
+	mfhi	t0
+	sd	t1,0(a0)
+	sd	t0,8(a0)
+	beqz	a2,.L_bn_sqr_words_return
+
+	ld	t0,8(a1)
+	dmultu	t0,t0
+	subu	a2,1
+	mflo	t1
+	mfhi	t0
+	sd	t1,16(a0)
+	sd	t0,24(a0)
+	beqz	a2,.L_bn_sqr_words_return
+
+	ld	t0,16(a1)
+	dmultu	t0,t0
+	mflo	t1
+	mfhi	t0
+	sd	t1,32(a0)
+	sd	t0,40(a0)
+	jr	ra
+END(bn_sqr_words)
+
+LEAF(bn_add_words)
+	.align	5
+	.set	noreorder
+	bgtzl	a3,.L_bn_add_words_proceed
+	ld	t0,0(a1)
+	jr	ra
+	move	v0,zero
+	.set	reorder
+
+.L_bn_add_words_proceed:
+	li	MINUS4,-4
+	and	AT,a3,MINUS4
+	move	v0,zero
+	beqz	AT,.L_bn_add_words_tail
+
+.L_bn_add_words_loop:
+	ld	ta0,0(a2)
+	ld	t1,8(a1)
+	ld	ta1,8(a2)
+	ld	t2,16(a1)
+	ld	ta2,16(a2)
+	ld	t3,24(a1)
+	ld	ta3,24(a2)
+	daddu	ta0,t0
+	subu	a3,4
+	sltu	t8,ta0,t0
+	daddu	t0,ta0,v0
+	PTR_ADD	a0,32
+	sltu	v0,t0,ta0
+	sd	t0,-32(a0)
+	daddu	v0,t8
+
+	daddu	ta1,t1
+	PTR_ADD	a1,32
+	sltu	t9,ta1,t1
+	daddu	t1,ta1,v0
+	PTR_ADD	a2,32
+	sltu	v0,t1,ta1
+	sd	t1,-24(a0)
+	daddu	v0,t9
+
+	daddu	ta2,t2
+	and	AT,a3,MINUS4
+	sltu	t8,ta2,t2
+	daddu	t2,ta2,v0
+	sltu	v0,t2,ta2
+	sd	t2,-16(a0)
+	daddu	v0,t8
+	
+	daddu	ta3,t3
+	sltu	t9,ta3,t3
+	daddu	t3,ta3,v0
+	sltu	v0,t3,ta3
+	sd	t3,-8(a0)
+	daddu	v0,t9
+	
+	.set	noreorder
+	bgtzl	AT,.L_bn_add_words_loop
+	ld	t0,0(a1)
+
+	bnezl	a3,.L_bn_add_words_tail
+	ld	t0,0(a1)
+	.set	reorder
+
+.L_bn_add_words_return:
+	jr	ra
+
+.L_bn_add_words_tail:
+	ld	ta0,0(a2)
+	daddu	ta0,t0
+	subu	a3,1
+	sltu	t8,ta0,t0
+	daddu	t0,ta0,v0
+	sltu	v0,t0,ta0
+	sd	t0,0(a0)
+	daddu	v0,t8
+	beqz	a3,.L_bn_add_words_return
+
+	ld	t1,8(a1)
+	ld	ta1,8(a2)
+	daddu	ta1,t1
+	subu	a3,1
+	sltu	t9,ta1,t1
+	daddu	t1,ta1,v0
+	sltu	v0,t1,ta1
+	sd	t1,8(a0)
+	daddu	v0,t9
+	beqz	a3,.L_bn_add_words_return
+
+	ld	t2,16(a1)
+	ld	ta2,16(a2)
+	daddu	ta2,t2
+	sltu	t8,ta2,t2
+	daddu	t2,ta2,v0
+	sltu	v0,t2,ta2
+	sd	t2,16(a0)
+	daddu	v0,t8
+	jr	ra
+END(bn_add_words)
+
+LEAF(bn_sub_words)
+	.align	5
+	.set	noreorder
+	bgtzl	a3,.L_bn_sub_words_proceed
+	ld	t0,0(a1)
+	jr	ra
+	move	v0,zero
+	.set	reorder
+
+.L_bn_sub_words_proceed:
+	li	MINUS4,-4
+	and	AT,a3,MINUS4
+	move	v0,zero
+	beqz	AT,.L_bn_sub_words_tail
+
+.L_bn_sub_words_loop:
+	ld	ta0,0(a2)
+	ld	t1,8(a1)
+	ld	ta1,8(a2)
+	ld	t2,16(a1)
+	ld	ta2,16(a2)
+	ld	t3,24(a1)
+	ld	ta3,24(a2)
+	sltu	t8,t0,ta0
+	dsubu	t0,ta0
+	subu	a3,4
+	dsubu	ta0,t0,v0
+	and	AT,a3,MINUS4
+	sd	ta0,0(a0)
+	MOVNZ	(t0,v0,t8)
+
+	sltu	t9,t1,ta1
+	dsubu	t1,ta1
+	PTR_ADD	a0,32
+	dsubu	ta1,t1,v0
+	PTR_ADD	a1,32
+	sd	ta1,-24(a0)
+	MOVNZ	(t1,v0,t9)
+
+
+	sltu	t8,t2,ta2
+	dsubu	t2,ta2
+	dsubu	ta2,t2,v0
+	PTR_ADD	a2,32
+	sd	ta2,-16(a0)
+	MOVNZ	(t2,v0,t8)
+
+	sltu	t9,t3,ta3
+	dsubu	t3,ta3
+	dsubu	ta3,t3,v0
+	sd	ta3,-8(a0)
+	MOVNZ	(t3,v0,t9)
+
+	.set	noreorder
+	bgtzl	AT,.L_bn_sub_words_loop
+	ld	t0,0(a1)
+
+	bnezl	a3,.L_bn_sub_words_tail
+	ld	t0,0(a1)
+	.set	reorder
+
+.L_bn_sub_words_return:
+	jr	ra
+
+.L_bn_sub_words_tail:
+	ld	ta0,0(a2)
+	subu	a3,1
+	sltu	t8,t0,ta0
+	dsubu	t0,ta0
+	dsubu	ta0,t0,v0
+	MOVNZ	(t0,v0,t8)
+	sd	ta0,0(a0)
+	beqz	a3,.L_bn_sub_words_return
+
+	ld	t1,8(a1)
+	subu	a3,1
+	ld	ta1,8(a2)
+	sltu	t9,t1,ta1
+	dsubu	t1,ta1
+	dsubu	ta1,t1,v0
+	MOVNZ	(t1,v0,t9)
+	sd	ta1,8(a0)
+	beqz	a3,.L_bn_sub_words_return
+
+	ld	t2,16(a1)
+	ld	ta2,16(a2)
+	sltu	t8,t2,ta2
+	dsubu	t2,ta2
+	dsubu	ta2,t2,v0
+	MOVNZ	(t2,v0,t8)
+	sd	ta2,16(a0)
+	jr	ra
+END(bn_sub_words)
+
+#undef	MINUS4
+
+LEAF(bn_div_words)
+	.align	5
+	.set	noreorder
+	bnezl	a2,.L_bn_div_words_proceed
+	move	t0,zero
+	jr	ra
+	li	v0,-1		/* I'd rather signal div-by-zero
+				 * which can be done with 'break 7' */
+	.set	reorder
+
+.L_bn_div_words_proceed:
+	bltz	a2,.L_bn_div_words_body
+	.set	noreorder
+	dsll	a2,1
+	bgtz	a2,.-4
+	addu	t0,1
+	.set	reorder
+	negu	t1,t0
+	li	t2,-1
+	dsll	t2,t1
+	and	t2,a0
+	dsrl	AT,a1,t1
+	.set	noreorder
+	bnezl	t2,.+8
+	break	6		/* signal overflow */
+	.set	reorder
+	dsll	a0,t0
+	dsll	a1,t0
+	or	a0,AT
+
+#define	QT	ta0
+#define	DH	ta1
+#define	HH	ta2
+#define	MINUS1	ta3
+.L_bn_div_words_body:
+	dsrl	DH,a2,32
+	li	v1,2
+	sgeu	AT,a0,a2
+	li	MINUS1,-1
+	.set	noreorder
+	bnezl	AT,.+8
+	dsubu	a0,a2
+	.set	reorder
+
+.L_bn_div_words_outer_loop:
+	dsrl	HH,a0,32
+	subu	v1,1
+	dsrl	QT,MINUS1,32	/* q=0xffffffff */
+	beq	DH,HH,.L_bn_div_words_inner_loop
+	ddivu	zero,a0,DH
+	mflo	QT
+.L_bn_div_words_inner_loop:
+	dmultu	a2,QT
+	dsll	t3,a0,32
+	dsrl	AT,a1,32
+	or	t3,AT
+	mflo	t0
+	mfhi	t1
+	sltu	t2,t3,t0
+	seq	t8,HH,t1
+	sltu	AT,HH,t1
+	and	t2,t8
+	or	AT,t2
+	.set	noreorder
+	bnezl	AT,.L_bn_div_words_inner_loop
+	dsubu	QT,1
+	.set	reorder
+	
+	dsubu	a0,t3,t0
+	beqz	v1,.L_bn_div_words_outer_loop_done
+
+	dsll	a1,32
+	dsll	v0,QT,32
+	b	.L_bn_div_words_outer_loop
+
+.L_bn_div_words_outer_loop_done:
+	or	v0,QT
+	move	v1,a0	/* v1 contains remainder if one wants it */
+	jr	ra
+#undef	MINUS1
+#undef	HH
+#undef	DH
+#undef	QT
+END(bn_div_words)
+
+#define	a_0	t0
+#define	a_1	t1
+#define	a_2	t2
+#define	a_3	t3
+#define	b_0	ta0
+#define	b_1	ta1
+#define	b_2	ta2
+#define	b_3	ta3
+
+#define	a_4	s0
+#define	a_5	s2
+#define	a_6	s4
+#define	a_7	a1	/* once we load a[7] we don't need a anymore */
+#define	b_4	s1
+#define	b_5	s3
+#define	b_6	s5
+#define	b_7	a2	/* once we load b[7] we don't need b anymore */
+
+#define	t_1	t8
+#define	t_2	t9
+
+#define	c_1	v0
+#define	c_2	v1
+#define	c_3	a3
+
+#define	FRAME_SIZE	48
+
+LEAF(bn_mul_comba8)
+	.align	5
+	.set	noreorder
+	PTR_SUB	sp,FRAME_SIZE
+	.frame	sp,64,ra
+	.set	reorder
+	ld	a_0,0(a1)	/* If compiled with -mips3 options
+				 * assembler barks on this line with
+				 * "shouldn't have mult/div as last
+				 * instruction in bb (R10K bug)"
+				 * warning. If anybody out there has
+				 * a clue on what does "bb" mean and
+				 * how to circumvent this do send me
+				 * a note.
+				 *		<appro@fy.chalmers.se>
+				 */
+	ld	b_0,0(a2)
+	ld	a_1,8(a1)
+	ld	a_2,16(a1)
+	ld	a_3,24(a1)
+	ld	b_1,8(a2)
+	ld	b_2,16(a2)
+	ld	b_3,24(a2)
+	dmultu	a_0,b_0		/* mul_add_c(a[0],b[0],c1,c2,c3); */
+	sd	s0,0(sp)
+	sd	s1,8(sp)
+	sd	s2,16(sp)
+	sd	s3,24(sp)
+	sd	s4,32(sp)
+	sd	s5,40(sp)
+	mflo	c_1
+	mfhi	c_2
+
+	dmultu	a_0,b_1		/* mul_add_c(a[0],b[1],c2,c3,c1); */
+	ld	a_4,32(a1)
+	ld	a_5,40(a1)
+	ld	a_6,48(a1)
+	ld	a_7,56(a1)
+	ld	b_4,32(a2)
+	ld	b_5,40(a2)
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	c_3,t_2,AT
+	dmultu	a_1,b_0		/* mul_add_c(a[1],b[0],c2,c3,c1); */
+	ld	b_6,48(a2)
+	ld	b_7,56(a2)
+	sd	c_1,0(a0)	/* r[0]=c1; */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	t_2,AT
+	daddu	c_3,t_2
+	sltu	c_1,c_3,t_2
+	sd	c_2,8(a0)	/* r[1]=c2; */
+
+	dmultu	a_2,b_0		/* mul_add_c(a[2],b[0],c3,c1,c2); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	t_2,AT
+	daddu	c_1,t_2
+	dmultu	a_1,b_1		/* mul_add_c(a[1],b[1],c3,c1,c2); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	t_2,AT
+	daddu	c_1,t_2
+	sltu	c_2,c_1,t_2
+	dmultu	a_0,b_2		/* mul_add_c(a[0],b[2],c3,c1,c2); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	t_2,AT
+	daddu	c_1,t_2
+	sltu	AT,c_1,t_2
+	daddu	c_2,AT
+	sd	c_3,16(a0)	/* r[2]=c3; */
+
+	dmultu	a_0,b_3		/* mul_add_c(a[0],b[3],c1,c2,c3); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	t_2,AT
+	daddu	c_2,t_2
+	dmultu	a_1,b_2		/* mul_add_c(a[1],b[2],c1,c2,c3); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	t_2,AT
+	daddu	c_2,t_2
+	sltu	c_3,c_2,t_2
+	dmultu	a_2,b_1		/* mul_add_c(a[2],b[1],c1,c2,c3); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	t_2,AT
+	daddu	c_2,t_2
+	sltu	AT,c_2,t_2
+	daddu	c_3,AT
+	dmultu	a_3,b_0		/* mul_add_c(a[3],b[0],c1,c2,c3); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	t_2,AT
+	daddu	c_2,t_2
+	sltu	AT,c_2,t_2
+	daddu	c_3,AT
+	sd	c_1,24(a0)	/* r[3]=c1; */
+
+	dmultu	a_4,b_0		/* mul_add_c(a[4],b[0],c2,c3,c1); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	t_2,AT
+	daddu	c_3,t_2
+	dmultu	a_3,b_1		/* mul_add_c(a[3],b[1],c2,c3,c1); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	t_2,AT
+	daddu	c_3,t_2
+	sltu	c_1,c_3,t_2
+	dmultu	a_2,b_2		/* mul_add_c(a[2],b[2],c2,c3,c1); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	t_2,AT
+	daddu	c_3,t_2
+	sltu	AT,c_3,t_2
+	daddu	c_1,AT
+	dmultu	a_1,b_3		/* mul_add_c(a[1],b[3],c2,c3,c1); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	t_2,AT
+	daddu	c_3,t_2
+	sltu	AT,c_3,t_2
+	daddu	c_1,AT
+	dmultu	a_0,b_4		/* mul_add_c(a[0],b[4],c2,c3,c1); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	t_2,AT
+	daddu	c_3,t_2
+	sltu	AT,c_3,t_2
+	daddu	c_1,AT
+	sd	c_2,32(a0)	/* r[4]=c2; */
+
+	dmultu	a_0,b_5		/* mul_add_c(a[0],b[5],c3,c1,c2); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	t_2,AT
+	daddu	c_1,t_2
+	dmultu	a_1,b_4		/* mul_add_c(a[1],b[4],c3,c1,c2); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	t_2,AT
+	daddu	c_1,t_2
+	sltu	c_2,c_1,t_2
+	dmultu	a_2,b_3		/* mul_add_c(a[2],b[3],c3,c1,c2); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	t_2,AT
+	daddu	c_1,t_2
+	sltu	AT,c_1,t_2
+	daddu	c_2,AT
+	dmultu	a_3,b_2		/* mul_add_c(a[3],b[2],c3,c1,c2); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	t_2,AT
+	daddu	c_1,t_2
+	sltu	AT,c_1,t_2
+	daddu	c_2,AT
+	dmultu	a_4,b_1		/* mul_add_c(a[4],b[1],c3,c1,c2); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	t_2,AT
+	daddu	c_1,t_2
+	sltu	AT,c_1,t_2
+	daddu	c_2,AT
+	dmultu	a_5,b_0		/* mul_add_c(a[5],b[0],c3,c1,c2); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	t_2,AT
+	daddu	c_1,t_2
+	sltu	AT,c_1,t_2
+	daddu	c_2,AT
+	sd	c_3,40(a0)	/* r[5]=c3; */
+
+	dmultu	a_6,b_0		/* mul_add_c(a[6],b[0],c1,c2,c3); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	t_2,AT
+	daddu	c_2,t_2
+	dmultu	a_5,b_1		/* mul_add_c(a[5],b[1],c1,c2,c3); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	t_2,AT
+	daddu	c_2,t_2
+	sltu	c_3,c_2,t_2
+	dmultu	a_4,b_2		/* mul_add_c(a[4],b[2],c1,c2,c3); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	t_2,AT
+	daddu	c_2,t_2
+	sltu	AT,c_2,t_2
+	daddu	c_3,AT
+	dmultu	a_3,b_3		/* mul_add_c(a[3],b[3],c1,c2,c3); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	t_2,AT
+	daddu	c_2,t_2
+	sltu	AT,c_2,t_2
+	daddu	c_3,AT
+	dmultu	a_2,b_4		/* mul_add_c(a[2],b[4],c1,c2,c3); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	t_2,AT
+	daddu	c_2,t_2
+	sltu	AT,c_2,t_2
+	daddu	c_3,AT
+	dmultu	a_1,b_5		/* mul_add_c(a[1],b[5],c1,c2,c3); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	t_2,AT
+	daddu	c_2,t_2
+	sltu	AT,c_2,t_2
+	daddu	c_3,AT
+	dmultu	a_0,b_6		/* mul_add_c(a[0],b[6],c1,c2,c3); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	t_2,AT
+	daddu	c_2,t_2
+	sltu	AT,c_2,t_2
+	daddu	c_3,AT
+	sd	c_1,48(a0)	/* r[6]=c1; */
+
+	dmultu	a_0,b_7		/* mul_add_c(a[0],b[7],c2,c3,c1); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	t_2,AT
+	daddu	c_3,t_2
+	dmultu	a_1,b_6		/* mul_add_c(a[1],b[6],c2,c3,c1); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	t_2,AT
+	daddu	c_3,t_2
+	sltu	c_1,c_3,t_2
+	dmultu	a_2,b_5		/* mul_add_c(a[2],b[5],c2,c3,c1); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	t_2,AT
+	daddu	c_3,t_2
+	sltu	AT,c_3,t_2
+	daddu	c_1,AT
+	dmultu	a_3,b_4		/* mul_add_c(a[3],b[4],c2,c3,c1); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	t_2,AT
+	daddu	c_3,t_2
+	sltu	AT,c_3,t_2
+	daddu	c_1,AT
+	dmultu	a_4,b_3		/* mul_add_c(a[4],b[3],c2,c3,c1); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	t_2,AT
+	daddu	c_3,t_2
+	sltu	AT,c_3,t_2
+	daddu	c_1,AT
+	dmultu	a_5,b_2		/* mul_add_c(a[5],b[2],c2,c3,c1); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	t_2,AT
+	daddu	c_3,t_2
+	sltu	AT,c_3,t_2
+	daddu	c_1,AT
+	dmultu	a_6,b_1		/* mul_add_c(a[6],b[1],c2,c3,c1); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	t_2,AT
+	daddu	c_3,t_2
+	sltu	AT,c_3,t_2
+	daddu	c_1,AT
+	dmultu	a_7,b_0		/* mul_add_c(a[7],b[0],c2,c3,c1); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	t_2,AT
+	daddu	c_3,t_2
+	sltu	AT,c_3,t_2
+	daddu	c_1,AT
+	sd	c_2,56(a0)	/* r[7]=c2; */
+
+	dmultu	a_7,b_1		/* mul_add_c(a[7],b[1],c3,c1,c2); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	t_2,AT
+	daddu	c_1,t_2
+	dmultu	a_6,b_2		/* mul_add_c(a[6],b[2],c3,c1,c2); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	t_2,AT
+	daddu	c_1,t_2
+	sltu	c_2,c_1,t_2
+	dmultu	a_5,b_3		/* mul_add_c(a[5],b[3],c3,c1,c2); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	t_2,AT
+	daddu	c_1,t_2
+	sltu	AT,c_1,t_2
+	daddu	c_2,AT
+	dmultu	a_4,b_4		/* mul_add_c(a[4],b[4],c3,c1,c2); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	t_2,AT
+	daddu	c_1,t_2
+	sltu	AT,c_1,t_2
+	daddu	c_2,AT
+	dmultu	a_3,b_5		/* mul_add_c(a[3],b[5],c3,c1,c2); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	t_2,AT
+	daddu	c_1,t_2
+	sltu	AT,c_1,t_2
+	daddu	c_2,AT
+	dmultu	a_2,b_6		/* mul_add_c(a[2],b[6],c3,c1,c2); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	t_2,AT
+	daddu	c_1,t_2
+	sltu	AT,c_1,t_2
+	daddu	c_2,AT
+	dmultu	a_1,b_7		/* mul_add_c(a[1],b[7],c3,c1,c2); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	t_2,AT
+	daddu	c_1,t_2
+	sltu	AT,c_1,t_2
+	daddu	c_2,AT
+	sd	c_3,64(a0)	/* r[8]=c3; */
+
+	dmultu	a_2,b_7		/* mul_add_c(a[2],b[7],c1,c2,c3); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	t_2,AT
+	daddu	c_2,t_2
+	dmultu	a_3,b_6		/* mul_add_c(a[3],b[6],c1,c2,c3); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	t_2,AT
+	daddu	c_2,t_2
+	sltu	c_3,c_2,t_2
+	dmultu	a_4,b_5		/* mul_add_c(a[4],b[5],c1,c2,c3); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	t_2,AT
+	daddu	c_2,t_2
+	sltu	AT,c_2,t_2
+	daddu	c_3,AT
+	dmultu	a_5,b_4		/* mul_add_c(a[5],b[4],c1,c2,c3); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	t_2,AT
+	daddu	c_2,t_2
+	sltu	AT,c_2,t_2
+	daddu	c_3,AT
+	dmultu	a_6,b_3		/* mul_add_c(a[6],b[3],c1,c2,c3); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	t_2,AT
+	daddu	c_2,t_2
+	sltu	AT,c_2,t_2
+	daddu	c_3,AT
+	dmultu	a_7,b_2		/* mul_add_c(a[7],b[2],c1,c2,c3); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	t_2,AT
+	daddu	c_2,t_2
+	sltu	AT,c_2,t_2
+	daddu	c_3,AT
+	sd	c_1,72(a0)	/* r[9]=c1; */
+
+	dmultu	a_7,b_3		/* mul_add_c(a[7],b[3],c2,c3,c1); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	t_2,AT
+	daddu	c_3,t_2
+	dmultu	a_6,b_4		/* mul_add_c(a[6],b[4],c2,c3,c1); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	t_2,AT
+	daddu	c_3,t_2
+	sltu	c_1,c_3,t_2
+	dmultu	a_5,b_5		/* mul_add_c(a[5],b[5],c2,c3,c1); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	t_2,AT
+	daddu	c_3,t_2
+	sltu	AT,c_3,t_2
+	daddu	c_1,AT
+	dmultu	a_4,b_6		/* mul_add_c(a[4],b[6],c2,c3,c1); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	t_2,AT
+	daddu	c_3,t_2
+	sltu	AT,c_3,t_2
+	daddu	c_1,AT
+	dmultu	a_3,b_7		/* mul_add_c(a[3],b[7],c2,c3,c1); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	t_2,AT
+	daddu	c_3,t_2
+	sltu	AT,c_3,t_2
+	daddu	c_1,AT
+	sd	c_2,80(a0)	/* r[10]=c2; */
+
+	dmultu	a_4,b_7		/* mul_add_c(a[4],b[7],c3,c1,c2); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	t_2,AT
+	daddu	c_1,t_2
+	dmultu	a_5,b_6		/* mul_add_c(a[5],b[6],c3,c1,c2); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	t_2,AT
+	daddu	c_1,t_2
+	sltu	c_2,c_1,t_2
+	dmultu	a_6,b_5		/* mul_add_c(a[6],b[5],c3,c1,c2); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	t_2,AT
+	daddu	c_1,t_2
+	sltu	AT,c_1,t_2
+	daddu	c_2,AT
+	dmultu	a_7,b_4		/* mul_add_c(a[7],b[4],c3,c1,c2); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	t_2,AT
+	daddu	c_1,t_2
+	sltu	AT,c_1,t_2
+	daddu	c_2,AT
+	sd	c_3,88(a0)	/* r[11]=c3; */
+
+	dmultu	a_7,b_5		/* mul_add_c(a[7],b[5],c1,c2,c3); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	t_2,AT
+	daddu	c_2,t_2
+	dmultu	a_6,b_6		/* mul_add_c(a[6],b[6],c1,c2,c3); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	t_2,AT
+	daddu	c_2,t_2
+	sltu	c_3,c_2,t_2
+	dmultu	a_5,b_7		/* mul_add_c(a[5],b[7],c1,c2,c3); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	t_2,AT
+	daddu	c_2,t_2
+	sltu	AT,c_2,t_2
+	daddu	c_3,AT
+	sd	c_1,96(a0)	/* r[12]=c1; */
+
+	dmultu	a_6,b_7		/* mul_add_c(a[6],b[7],c2,c3,c1); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	t_2,AT
+	daddu	c_3,t_2
+	dmultu	a_7,b_6		/* mul_add_c(a[7],b[6],c2,c3,c1); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	t_2,AT
+	daddu	c_3,t_2
+	sltu	c_1,c_3,t_2
+	sd	c_2,104(a0)	/* r[13]=c2; */
+
+	dmultu	a_7,b_7		/* mul_add_c(a[7],b[7],c3,c1,c2); */
+	ld	s0,0(sp)
+	ld	s1,8(sp)
+	ld	s2,16(sp)
+	ld	s3,24(sp)
+	ld	s4,32(sp)
+	ld	s5,40(sp)
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	t_2,AT
+	daddu	c_1,t_2
+	sd	c_3,112(a0)	/* r[14]=c3; */
+	sd	c_1,120(a0)	/* r[15]=c1; */
+
+	PTR_ADD	sp,FRAME_SIZE
+
+	jr	ra
+END(bn_mul_comba8)
+
+LEAF(bn_mul_comba4)
+	.align	5
+	.set	reorder
+	ld	a_0,0(a1)
+	ld	b_0,0(a2)
+	ld	a_1,8(a1)
+	ld	a_2,16(a1)
+	dmultu	a_0,b_0		/* mul_add_c(a[0],b[0],c1,c2,c3); */
+	ld	a_3,24(a1)
+	ld	b_1,8(a2)
+	ld	b_2,16(a2)
+	ld	b_3,24(a2)
+	mflo	c_1
+	mfhi	c_2
+	sd	c_1,0(a0)
+
+	dmultu	a_0,b_1		/* mul_add_c(a[0],b[1],c2,c3,c1); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	c_3,t_2,AT
+	dmultu	a_1,b_0		/* mul_add_c(a[1],b[0],c2,c3,c1); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	t_2,AT
+	daddu	c_3,t_2
+	sltu	c_1,c_3,t_2
+	sd	c_2,8(a0)
+
+	dmultu	a_2,b_0		/* mul_add_c(a[2],b[0],c3,c1,c2); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	t_2,AT
+	daddu	c_1,t_2
+	dmultu	a_1,b_1		/* mul_add_c(a[1],b[1],c3,c1,c2); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	t_2,AT
+	daddu	c_1,t_2
+	sltu	c_2,c_1,t_2
+	dmultu	a_0,b_2		/* mul_add_c(a[0],b[2],c3,c1,c2); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	t_2,AT
+	daddu	c_1,t_2
+	sltu	AT,c_1,t_2
+	daddu	c_2,AT
+	sd	c_3,16(a0)
+
+	dmultu	a_0,b_3		/* mul_add_c(a[0],b[3],c1,c2,c3); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	t_2,AT
+	daddu	c_2,t_2
+	dmultu	a_1,b_2		/* mul_add_c(a[1],b[2],c1,c2,c3); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	t_2,AT
+	daddu	c_2,t_2
+	sltu	c_3,c_2,t_2
+	dmultu	a_2,b_1		/* mul_add_c(a[2],b[1],c1,c2,c3); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	t_2,AT
+	daddu	c_2,t_2
+	sltu	AT,c_2,t_2
+	daddu	c_3,AT
+	dmultu	a_3,b_0		/* mul_add_c(a[3],b[0],c1,c2,c3); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	t_2,AT
+	daddu	c_2,t_2
+	sltu	AT,c_2,t_2
+	daddu	c_3,AT
+	sd	c_1,24(a0)
+
+	dmultu	a_3,b_1		/* mul_add_c(a[3],b[1],c2,c3,c1); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	t_2,AT
+	daddu	c_3,t_2
+	dmultu	a_2,b_2		/* mul_add_c(a[2],b[2],c2,c3,c1); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	t_2,AT
+	daddu	c_3,t_2
+	sltu	c_1,c_3,t_2
+	dmultu	a_1,b_3		/* mul_add_c(a[1],b[3],c2,c3,c1); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	t_2,AT
+	daddu	c_3,t_2
+	sltu	AT,c_3,t_2
+	daddu	c_1,AT
+	sd	c_2,32(a0)
+
+	dmultu	a_2,b_3		/* mul_add_c(a[2],b[3],c3,c1,c2); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	t_2,AT
+	daddu	c_1,t_2
+	dmultu	a_3,b_2		/* mul_add_c(a[3],b[2],c3,c1,c2); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	t_2,AT
+	daddu	c_1,t_2
+	sltu	c_2,c_1,t_2
+	sd	c_3,40(a0)
+
+	dmultu	a_3,b_3		/* mul_add_c(a[3],b[3],c1,c2,c3); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	t_2,AT
+	daddu	c_2,t_2
+	sd	c_1,48(a0)
+	sd	c_2,56(a0)
+
+	jr	ra
+END(bn_mul_comba4)
+
+#undef	a_4
+#undef	a_5
+#undef	a_6
+#undef	a_7
+#define	a_4	b_0
+#define	a_5	b_1
+#define	a_6	b_2
+#define	a_7	b_3
+
+LEAF(bn_sqr_comba8)
+	.align	5
+	.set	reorder
+	ld	a_0,0(a1)
+	ld	a_1,8(a1)
+	ld	a_2,16(a1)
+	ld	a_3,24(a1)
+
+	dmultu	a_0,a_0		/* mul_add_c(a[0],b[0],c1,c2,c3); */
+	ld	a_4,32(a1)
+	ld	a_5,40(a1)
+	ld	a_6,48(a1)
+	ld	a_7,56(a1)
+	mflo	c_1
+	mfhi	c_2
+	sd	c_1,0(a0)
+
+	dmultu	a_0,a_1		/* mul_add_c2(a[0],b[1],c2,c3,c1); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	c_3,t_2,AT
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	t_2,AT
+	daddu	c_3,t_2
+	sltu	c_1,c_3,t_2
+	sd	c_2,8(a0)
+
+	dmultu	a_2,a_0		/* mul_add_c2(a[2],b[0],c3,c1,c2); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	a2,t_2,AT
+	daddu	c_1,a2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	t_2,AT
+	daddu	c_1,t_2
+	sltu	c_2,c_1,t_2
+	dmultu	a_1,a_1		/* mul_add_c(a[1],b[1],c3,c1,c2); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	t_2,AT
+	daddu	c_1,t_2
+	sltu	AT,c_1,t_2
+	daddu	c_2,AT
+	sd	c_3,16(a0)
+
+	dmultu	a_0,a_3		/* mul_add_c2(a[0],b[3],c1,c2,c3); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	a2,t_2,AT
+	daddu	c_2,a2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	t_2,AT
+	daddu	c_2,t_2
+	sltu	c_3,c_2,t_2
+	dmultu	a_1,a_2		/* mul_add_c2(a[1],b[2],c1,c2,c3); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	a2,t_2,AT
+	daddu	c_2,a2
+	sltu	AT,c_2,a2
+	daddu	c_3,AT
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	t_2,AT
+	daddu	c_2,t_2
+	sltu	AT,c_2,t_2
+	daddu	c_3,AT
+	sd	c_1,24(a0)
+
+	dmultu	a_4,a_0		/* mul_add_c2(a[4],b[0],c2,c3,c1); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	a2,t_2,AT
+	daddu	c_3,a2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	t_2,AT
+	daddu	c_3,t_2
+	sltu	c_1,c_3,t_2
+	dmultu	a_3,a_1		/* mul_add_c2(a[3],b[1],c2,c3,c1); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	a2,t_2,AT
+	daddu	c_3,a2
+	sltu	AT,c_3,a2
+	daddu	c_1,AT
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	t_2,AT
+	daddu	c_3,t_2
+	sltu	AT,c_3,t_2
+	daddu	c_1,AT
+	dmultu	a_2,a_2		/* mul_add_c(a[2],b[2],c2,c3,c1); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	t_2,AT
+	daddu	c_3,t_2
+	sltu	AT,c_3,t_2
+	daddu	c_1,AT
+	sd	c_2,32(a0)
+
+	dmultu	a_0,a_5		/* mul_add_c2(a[0],b[5],c3,c1,c2); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	a2,t_2,AT
+	daddu	c_1,a2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	t_2,AT
+	daddu	c_1,t_2
+	sltu	c_2,c_1,t_2
+	dmultu	a_1,a_4		/* mul_add_c2(a[1],b[4],c3,c1,c2); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	a2,t_2,AT
+	daddu	c_1,a2
+	sltu	AT,c_1,a2
+	daddu	c_2,AT
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	t_2,AT
+	daddu	c_1,t_2
+	sltu	AT,c_1,t_2
+	daddu	c_2,AT
+	dmultu	a_2,a_3		/* mul_add_c2(a[2],b[3],c3,c1,c2); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	a2,t_2,AT
+	daddu	c_1,a2
+	sltu	AT,c_1,a2
+	daddu	c_2,AT
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	t_2,AT
+	daddu	c_1,t_2
+	sltu	AT,c_1,t_2
+	daddu	c_2,AT
+	sd	c_3,40(a0)
+
+	dmultu	a_6,a_0		/* mul_add_c2(a[6],b[0],c1,c2,c3); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	a2,t_2,AT
+	daddu	c_2,a2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	t_2,AT
+	daddu	c_2,t_2
+	sltu	c_3,c_2,t_2
+	dmultu	a_5,a_1		/* mul_add_c2(a[5],b[1],c1,c2,c3); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	a2,t_2,AT
+	daddu	c_2,a2
+	sltu	AT,c_2,a2
+	daddu	c_3,AT
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	t_2,AT
+	daddu	c_2,t_2
+	sltu	AT,c_2,t_2
+	daddu	c_3,AT
+	dmultu	a_4,a_2		/* mul_add_c2(a[4],b[2],c1,c2,c3); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	a2,t_2,AT
+	daddu	c_2,a2
+	sltu	AT,c_2,a2
+	daddu	c_3,AT
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	t_2,AT
+	daddu	c_2,t_2
+	sltu	AT,c_2,t_2
+	daddu	c_3,AT
+	dmultu	a_3,a_3		/* mul_add_c(a[3],b[3],c1,c2,c3); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	t_2,AT
+	daddu	c_2,t_2
+	sltu	AT,c_2,t_2
+	daddu	c_3,AT
+	sd	c_1,48(a0)
+
+	dmultu	a_0,a_7		/* mul_add_c2(a[0],b[7],c2,c3,c1); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	a2,t_2,AT
+	daddu	c_3,a2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	t_2,AT
+	daddu	c_3,t_2
+	sltu	c_1,c_3,t_2
+	dmultu	a_1,a_6		/* mul_add_c2(a[1],b[6],c2,c3,c1); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	a2,t_2,AT
+	daddu	c_3,a2
+	sltu	AT,c_3,a2
+	daddu	c_1,AT
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	t_2,AT
+	daddu	c_3,t_2
+	sltu	AT,c_3,t_2
+	daddu	c_1,AT
+	dmultu	a_2,a_5		/* mul_add_c2(a[2],b[5],c2,c3,c1); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	a2,t_2,AT
+	daddu	c_3,a2
+	sltu	AT,c_3,a2
+	daddu	c_1,AT
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	t_2,AT
+	daddu	c_3,t_2
+	sltu	AT,c_3,t_2
+	daddu	c_1,AT
+	dmultu	a_3,a_4		/* mul_add_c2(a[3],b[4],c2,c3,c1); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	a2,t_2,AT
+	daddu	c_3,a2
+	sltu	AT,c_3,a2
+	daddu	c_1,AT
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	t_2,AT
+	daddu	c_3,t_2
+	sltu	AT,c_3,t_2
+	daddu	c_1,AT
+	sd	c_2,56(a0)
+
+	dmultu	a_7,a_1		/* mul_add_c2(a[7],b[1],c3,c1,c2); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	a2,t_2,AT
+	daddu	c_1,a2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	t_2,AT
+	daddu	c_1,t_2
+	sltu	c_2,c_1,t_2
+	dmultu	a_6,a_2		/* mul_add_c2(a[6],b[2],c3,c1,c2); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	a2,t_2,AT
+	daddu	c_1,a2
+	sltu	AT,c_1,a2
+	daddu	c_2,AT
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	t_2,AT
+	daddu	c_1,t_2
+	sltu	AT,c_1,t_2
+	daddu	c_2,AT
+	dmultu	a_5,a_3		/* mul_add_c2(a[5],b[3],c3,c1,c2); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	a2,t_2,AT
+	daddu	c_1,a2
+	sltu	AT,c_1,a2
+	daddu	c_2,AT
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	t_2,AT
+	daddu	c_1,t_2
+	sltu	AT,c_1,t_2
+	daddu	c_2,AT
+	dmultu	a_4,a_4		/* mul_add_c(a[4],b[4],c3,c1,c2); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	t_2,AT
+	daddu	c_1,t_2
+	sltu	AT,c_1,t_2
+	daddu	c_2,AT
+	sd	c_3,64(a0)
+
+	dmultu	a_2,a_7		/* mul_add_c2(a[2],b[7],c1,c2,c3); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	a2,t_2,AT
+	daddu	c_2,a2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	t_2,AT
+	daddu	c_2,t_2
+	sltu	c_3,c_2,t_2
+	dmultu	a_3,a_6		/* mul_add_c2(a[3],b[6],c1,c2,c3); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	a2,t_2,AT
+	daddu	c_2,a2
+	sltu	AT,c_2,a2
+	daddu	c_3,AT
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	t_2,AT
+	daddu	c_2,t_2
+	sltu	AT,c_2,t_2
+	daddu	c_3,AT
+	dmultu	a_4,a_5		/* mul_add_c2(a[4],b[5],c1,c2,c3); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	a2,t_2,AT
+	daddu	c_2,a2
+	sltu	AT,c_2,a2
+	daddu	c_3,AT
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	t_2,AT
+	daddu	c_2,t_2
+	sltu	AT,c_2,t_2
+	daddu	c_3,AT
+	sd	c_1,72(a0)
+
+	dmultu	a_7,a_3		/* mul_add_c2(a[7],b[3],c2,c3,c1); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	a2,t_2,AT
+	daddu	c_3,a2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	t_2,AT
+	daddu	c_3,t_2
+	sltu	c_1,c_3,t_2
+	dmultu	a_6,a_4		/* mul_add_c2(a[6],b[4],c2,c3,c1); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	a2,t_2,AT
+	daddu	c_3,a2
+	sltu	AT,c_3,a2
+	daddu	c_1,AT
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	t_2,AT
+	daddu	c_3,t_2
+	sltu	AT,c_3,t_2
+	daddu	c_1,AT
+	dmultu	a_5,a_5		/* mul_add_c(a[5],b[5],c2,c3,c1); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	t_2,AT
+	daddu	c_3,t_2
+	sltu	AT,c_3,t_2
+	daddu	c_1,AT
+	sd	c_2,80(a0)
+
+	dmultu	a_4,a_7		/* mul_add_c2(a[4],b[7],c3,c1,c2); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	a2,t_2,AT
+	daddu	c_1,a2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	t_2,AT
+	daddu	c_1,t_2
+	sltu	c_2,c_1,t_2
+	dmultu	a_5,a_6		/* mul_add_c2(a[5],b[6],c3,c1,c2); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	a2,t_2,AT
+	daddu	c_1,a2
+	sltu	AT,c_1,a2
+	daddu	c_2,AT
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	t_2,AT
+	daddu	c_1,t_2
+	sltu	AT,c_1,t_2
+	daddu	c_2,AT
+	sd	c_3,88(a0)
+
+	dmultu	a_7,a_5		/* mul_add_c2(a[7],b[5],c1,c2,c3); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	a2,t_2,AT
+	daddu	c_2,a2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	t_2,AT
+	daddu	c_2,t_2
+	sltu	c_3,c_2,t_2
+	dmultu	a_6,a_6		/* mul_add_c(a[6],b[6],c1,c2,c3); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	t_2,AT
+	daddu	c_2,t_2
+	sltu	AT,c_2,t_2
+	daddu	c_3,AT
+	sd	c_1,96(a0)
+
+	dmultu	a_6,a_7		/* mul_add_c2(a[6],b[7],c2,c3,c1); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	a2,t_2,AT
+	daddu	c_3,a2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	t_2,AT
+	daddu	c_3,t_2
+	sltu	c_1,c_3,t_2
+	sd	c_2,104(a0)
+
+	dmultu	a_7,a_7		/* mul_add_c(a[7],b[7],c3,c1,c2); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	t_2,AT
+	daddu	c_1,t_2
+	sd	c_3,112(a0)
+	sd	c_1,120(a0)
+
+	jr	ra
+END(bn_sqr_comba8)
+
+LEAF(bn_sqr_comba4)
+	.align	5
+	.set	reorder
+	ld	a_0,0(a1)
+	ld	a_1,8(a1)
+	ld	a_2,16(a1)
+	ld	a_3,24(a1)
+	dmultu	a_0,a_0		/* mul_add_c(a[0],b[0],c1,c2,c3); */
+	mflo	c_1
+	mfhi	c_2
+	sd	c_1,0(a0)
+
+	dmultu	a_0,a_1		/* mul_add_c2(a[0],b[1],c2,c3,c1); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	c_3,t_2,AT
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	t_2,AT
+	daddu	c_3,t_2
+	sltu	c_1,c_3,t_2
+	sd	c_2,8(a0)
+
+	dmultu	a_2,a_0		/* mul_add_c2(a[2],b[0],c3,c1,c2); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	a2,t_2,AT
+	daddu	c_1,a2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	t_2,AT
+	daddu	c_1,t_2
+	sltu	c_2,c_1,t_2
+	dmultu	a_1,a_1		/* mul_add_c(a[1],b[1],c3,c1,c2); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	t_2,AT
+	daddu	c_1,t_2
+	sltu	AT,c_1,t_2
+	daddu	c_2,AT
+	sd	c_3,16(a0)
+
+	dmultu	a_0,a_3		/* mul_add_c2(a[0],b[3],c1,c2,c3); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	a2,t_2,AT
+	daddu	c_2,a2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	t_2,AT
+	daddu	c_2,t_2
+	sltu	c_3,c_2,t_2
+	dmultu	a_1,a_2		/* mul_add_c(a2[1],b[2],c1,c2,c3); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	a2,t_2,AT
+	daddu	c_2,a2
+	sltu	AT,c_2,a2
+	daddu	c_3,AT
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	t_2,AT
+	daddu	c_2,t_2
+	sltu	AT,c_2,t_2
+	daddu	c_3,AT
+	sd	c_1,24(a0)
+
+	dmultu	a_3,a_1		/* mul_add_c2(a[3],b[1],c2,c3,c1); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	a2,t_2,AT
+	daddu	c_3,a2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	t_2,AT
+	daddu	c_3,t_2
+	sltu	c_1,c_3,t_2
+	dmultu	a_2,a_2		/* mul_add_c(a[2],b[2],c2,c3,c1); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_2,t_1
+	sltu	AT,c_2,t_1
+	daddu	t_2,AT
+	daddu	c_3,t_2
+	sltu	AT,c_3,t_2
+	daddu	c_1,AT
+	sd	c_2,32(a0)
+
+	dmultu	a_2,a_3		/* mul_add_c2(a[2],b[3],c3,c1,c2); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	a2,t_2,AT
+	daddu	c_1,a2
+	daddu	c_3,t_1
+	sltu	AT,c_3,t_1
+	daddu	t_2,AT
+	daddu	c_1,t_2
+	sltu	c_2,c_1,t_2
+	sd	c_3,40(a0)
+
+	dmultu	a_3,a_3		/* mul_add_c(a[3],b[3],c1,c2,c3); */
+	mflo	t_1
+	mfhi	t_2
+	daddu	c_1,t_1
+	sltu	AT,c_1,t_1
+	daddu	t_2,AT
+	daddu	c_2,t_2
+	sd	c_1,48(a0)
+	sd	c_2,56(a0)
+
+	jr	ra
+END(bn_sqr_comba4)