Minor MIPS III/IV tune-up.

Configure

@@ -154,11 +154,11 @@ my %table=(
 # Only N32 and N64 ABIs are supported. If you need O32 ABI build, invoke
 # './Configure irix-[g]cc' manually.
 # -mips4 flag is added by ./config when appropriate.
-"irix-mips3-gcc","gcc:-mabi=n32 -mmips-as -O3 -DTERMIOS -DB_ENDIAN::(unknown)::MD2_CHAR RC4_INDEX RC4_CHAR DES_UNROLL DES_RISC2 DES_PTR BF_PTR SIXTY_FOUR_BIT:asm/mips3.o::",
-"irix-mips3-cc", "cc:-n32 -O2 -use_readonly_const -DTERMIOS -DB_ENDIAN::(unknown)::DES_PTR DES_RISC2 DES_UNROLL BF_PTR SIXTY_FOUR_BIT:asm/mips3.o::",
+"irix-mips3-gcc","gcc:-mabi=n32 -mmips-as -O3 -DTERMIOS -DB_ENDIAN -DBN_DIV3W::(unknown)::MD2_CHAR RC4_INDEX RC4_CHAR DES_UNROLL DES_RISC2 DES_PTR BF_PTR SIXTY_FOUR_BIT:asm/mips3.o::",
+"irix-mips3-cc", "cc:-n32 -O2 -use_readonly_const -DTERMIOS -DB_ENDIAN -DBN_DIV3W::(unknown)::DES_PTR DES_RISC2 DES_UNROLL BF_PTR SIXTY_FOUR_BIT:asm/mips3.o::",
 # N64 ABI builds.
-"irix64-mips4-gcc","gcc:-mabi=64 -mips4 -mmips-as -O3 -DTERMIOS -DB_ENDIAN::(unknown)::DES_RISC2 DES_UNROLL SIXTY_FOUR_BIT_LONG:asm/mips3.o::",
-"irix64-mips4-cc", "cc:-64 -mips4 -O2 -use_readonly_const -DTERMIOS -DB_ENDIAN::(unknown)::DES_RISC2 DES_UNROLL SIXTY_FOUR_BIT_LONG:asm/mips3.o::",
+"irix64-mips4-gcc","gcc:-mabi=64 -mips4 -mmips-as -O3 -DTERMIOS -DB_ENDIAN -DBN_DIV3W::(unknown)::DES_RISC2 DES_UNROLL SIXTY_FOUR_BIT_LONG:asm/mips3.o::",
+"irix64-mips4-cc", "cc:-64 -mips4 -O2 -use_readonly_const -DTERMIOS -DB_ENDIAN -DBN_DIV3W::(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/asm/mips3.s

@@ -395,32 +395,32 @@ LEAF(bn_add_words)
 
 .L_bn_add_words_loop:
 	ld	ta0,0(a2)
+	subu	a3,4
 	ld	t1,8(a1)
-	ld	ta1,8(a2)
+	and	AT,a3,MINUS4
 	ld	t2,16(a1)
-	ld	ta2,16(a2)
+	PTR_ADD	a2,32
 	ld	t3,24(a1)
-	ld	ta3,24(a2)
+	PTR_ADD	a0,32
+	ld	ta1,-24(a2)
+	PTR_ADD	a1,32
+	ld	ta2,-16(a2)
+	ld	ta3,-8(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
@@ -495,25 +495,26 @@ LEAF(bn_sub_words)
 
 .L_bn_sub_words_loop:
 	ld	ta0,0(a2)
+	subu	a3,4
 	ld	t1,8(a1)
-	ld	ta1,8(a2)
+	and	AT,a3,MINUS4
 	ld	t2,16(a1)
-	ld	ta2,16(a2)
+	PTR_ADD	a2,32
 	ld	t3,24(a1)
-	ld	ta3,24(a2)
+	PTR_ADD	a0,32
+	ld	ta1,-24(a2)
+	PTR_ADD	a1,32
+	ld	ta2,-16(a2)
+	ld	ta3,-8(a2)
 	sltu	t8,t0,ta0
 	dsubu	t0,ta0
-	subu	a3,4
 	dsubu	ta0,t0,v0
-	and	AT,a3,MINUS4
-	sd	ta0,0(a0)
+	sd	ta0,-32(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)
 
@@ -521,7 +522,6 @@ LEAF(bn_sub_words)
 	sltu	t8,t2,ta2
 	dsubu	t2,ta2
 	dsubu	ta2,t2,v0
-	PTR_ADD	a2,32
 	sd	ta2,-16(a0)
 	MOVNZ	(t2,v0,t8)
 
@@ -574,6 +574,51 @@ END(bn_sub_words)
 
 #undef	MINUS4
 
+.align 5
+LEAF(bn_div_3_words)
+	.set	reorder
+	move	a3,a0		/* we know that bn_div_words doesn't
+				 * touch a3, ta2, ta3 and preserves a2
+				 * so that we can save two arguments
+				 * and return address in registers
+				 * instead of stack:-)
+				 */
+	ld	a0,(a3)
+	move	ta2,a1
+	ld	a1,-8(a3)
+	move	ta3,ra
+	move	v1,zero
+	li	v0,-1
+	beq	a0,a2,.L_bn_div_3_words_skip_div
+	bal	bn_div_words
+	move	ra,ta3
+.L_bn_div_3_words_skip_div:
+	dmultu	ta2,v0
+	ld	t2,-16(a3)
+	move	ta0,zero
+	mfhi	t1
+	mflo	t0
+	sltu	t8,t1,v1
+.L_bn_div_3_words_inner_loop:
+	bnez	t8,.L_bn_div_3_words_inner_loop_done
+	sgeu	AT,t2,t0
+	seq	t9,t1,v1
+	and	AT,t9
+	sltu	t3,t0,ta2
+	daddu	v1,a2
+	dsubu	t1,t3
+	dsubu	t0,ta2
+	sltu	t8,t1,v1
+	sltu	ta0,v1,a2
+	or	t8,ta0
+	.set	noreorder
+	beqzl	AT,.L_bn_div_3_words_inner_loop
+	dsubu	v0,1
+	.set	reorder
+.L_bn_div_3_words_inner_loop_done:
+	jr	ra
+END(bn_div_3_words)
+
 .align	5
 LEAF(bn_div_words)
 	.set	noreorder
@@ -633,16 +678,16 @@ LEAF(bn_div_words)
 	seq	t8,HH,t1
 	sltu	AT,HH,t1
 	and	t2,t8
+	sltu	v0,t0,a2
 	or	AT,t2
 	.set	noreorder
 	beqz	AT,.L_bn_div_words_inner_loop1_done
-	sltu	t2,t0,a2
-	.set	reorder
-	dsubu	QT,1
+	dsubu	t1,v0
 	dsubu	t0,a2
-	dsubu	t1,t2
 	b	.L_bn_div_words_inner_loop1
-.L_bn_div_words_inner_loop1_done:	
+	dsubu	QT,1
+	.set	reorder
+.L_bn_div_words_inner_loop1_done:
 
 	dsll	a1,32
 	dsubu	a0,t3,t0
@@ -655,6 +700,7 @@ LEAF(bn_div_words)
 	ddivu	zero,a0,DH
 	mflo	QT
 .L_bn_div_words_skip_div2:
+#undef	DH
 	dmultu	a2,QT
 	dsll	t3,a0,32
 	dsrl	AT,a1,32
@@ -666,69 +712,26 @@ LEAF(bn_div_words)
 	seq	t8,HH,t1
 	sltu	AT,HH,t1
 	and	t2,t8
+	sltu	v1,t0,a2
 	or	AT,t2
 	.set	noreorder
 	beqz	AT,.L_bn_div_words_inner_loop2_done
-	sltu	t2,t0,a2
-	.set	reorder
-	dsubu	QT,1
+	dsubu	t1,v1
 	dsubu	t0,a2
-	dsubu	t1,t2
 	b	.L_bn_div_words_inner_loop2
+	dsubu	QT,1
+	.set	reorder
 .L_bn_div_words_inner_loop2_done:	
+#undef	HH
 
 	dsubu	a0,t3,t0
 	or	v0,QT
 	dsrl	v1,a0,t9	/* v1 contains remainder if anybody wants it */
 	dsrl	a2,t9		/* restore a2 */
 	jr	ra
-#undef	HH
-#undef	DH
 #undef	QT
 END(bn_div_words)
 
-.align 5
-LEAF(bn_div_3_words)
-	.set	reorder
-	move	a3,a0		/* we know that bn_div_words doesn't
-				 * touch a3, ta2, ta3 and preserves a2
-				 * so that we can save two arguments
-				 * and return address in registers
-				 * instead of stack:-)
-				 */
-	ld	a0,(a3)
-	move	ta2,a2
-	move	a2,a1
-	ld	a1,-8(a3)
-	move	ta3,ra
-	move	v1,zero
-	li	v0,-1
-	beq	a0,a2,.L_bn_div_3_words_skip_div
-	jal	bn_div_words
-	move	ra,ta3
-.L_bn_div_3_words_skip_div:
-	dmultu	ta2,v0
-	ld	t2,-16(a3)
-	mflo	t0
-	mfhi	t1
-.L_bn_div_3_words_inner_loop:
-	sgeu	AT,t2,t0
-	seq	t9,t1,v1
-	sltu	t8,t1,v1
-	and	AT,t9
-	or	AT,t8
-	bnez	AT,.L_bn_div_3_words_inner_loop_done
-	daddu	v1,a2
-	sltu	t3,t0,ta2
-	sltu	AT,v1,a2
-	dsubu	v0,1
-	dsubu	t0,ta2
-	dsubu	t1,t3
-	beqz	AT,.L_bn_div_3_words_inner_loop
-.L_bn_div_3_words_inner_loop_done:
-	jr	ra
-END(bn_div_3_words)
-
 #define	a_0	t0
 #define	a_1	t1
 #define	a_2	t2

crypto/bn/bn_div.c

@@ -202,7 +202,7 @@ int BN_div(BIGNUM *dv, BIGNUM *rm, const BIGNUM *num, const BIGNUM *divisor,
 		{
 		BN_ULONG q,l0;
 #ifdef BN_DIV3W
-		q=bn_div_3_words(wnump,d0,d1);
+		q=bn_div_3_words(wnump,d1,d0);
 #else
 
 #if !defined(NO_ASM) && !defined(PEDANTIC)
@@ -291,8 +291,8 @@ int BN_div(BIGNUM *dv, BIGNUM *rm, const BIGNUM *num, const BIGNUM *divisor,
 #endif
 		}
 #endif /* !BN_DIV3W */
-		wnum.d--; wnum.top++;
 		l0=bn_mul_words(tmp->d,sdiv->d,div_n,q);
+		wnum.d--; wnum.top++;
 		tmp->d[div_n]=l0;
 		for (j=div_n+1; j>0; j--)
 			if (tmp->d[j-1]) break;