From 6e0f4042c91114ad60cc67bc378004d606629e53 Mon Sep 17 00:00:00 2001
From: Nick Downing <nick@ndcode.org>
Date: Tue, 25 Jun 2019 20:34:18 +1000
Subject: [PATCH] Add division test, fix multiply bug, still a bug on hi bit
 set unsigned divisor

---
 .gitignore |   1 -
 Makefile   |   5 +-
 mul.c      |  46 ++++---
 mul2.c     |  30 -----
 sm3.asm    | 357 ++++++++++++++++++++++++++++++++++++++++++++++++++---
 5 files changed, 370 insertions(+), 69 deletions(-)
 delete mode 100644 mul2.c

diff --git a/.gitignore b/.gitignore
index 5ac53fc..84f7b90 100644
--- a/.gitignore
+++ b/.gitignore
@@ -9,4 +9,3 @@
 cordic
 div
 mul
-mul2
diff --git a/Makefile b/Makefile
index f7856c1..0abb477 100644
--- a/Makefile
+++ b/Makefile
@@ -1,4 +1,4 @@
-all: div mul mul2 cordic
+all: div mul cordic
 
 div: div.c
 	gcc -o $@ $^
@@ -6,8 +6,5 @@ div: div.c
 mul: mul.c
 	gcc -o $@ $^
 
-mul2: mul2.c
-	gcc -o $@ $^
-
 cordic: cordic.c
 	gcc -o $@ $^
diff --git a/mul.c b/mul.c
index c77001b..a141a3b 100644
--- a/mul.c
+++ b/mul.c
@@ -1,30 +1,36 @@
 #include <stdio.h>
 
 int main(void) {
-  printf("%08x\n", 0x1234 * 0x56);
-  printf("%08x\n", 0x6543 * 0x21);
-  printf("%08x\n", 0xb975 * 0x31);
-  printf("%08x\n", 0xdb97 * 0x531);
+  printf("%08x\n", 0x00001234 * 0x00000056);
+  printf("%08x\n", 0x00006543 * 0x00000021);
+  printf("%08x\n", 0x0000b975 * 0x00000031);
+  printf("%08x\n", 0x0000db97 * 0x00000531);
 
-  printf("%08x\n", 0x1234 * 0x56);
-  printf("%08x\n", 0x6543 * 0x21);
-  printf("%08x\n", (int)0xffffb975 * 0x31);
-  printf("%08x\n", (int)0xffffdb97 * 0x531);
+  printf("%08x\n", 0x00001234 * 0x00000056);
+  printf("%08x\n", 0x00006543 * 0x00000021);
+  printf("%08x\n", (int)0xffffb975 * 0x00000031);
+  printf("%08x\n", (int)0xffffdb97 * 0x00000531);
 
-  printf("%08x\n", -0x1234 * 0x56);
-  printf("%08x\n", -0x6543 * 0x21);
-  printf("%08x\n", -(int)0xffffb975 * 0x31);
-  printf("%08x\n", -(int)0xffffdb97 * 0x531);
+  printf("%08x\n", -0x00001234 * 0x00000056);
+  printf("%08x\n", -0x00006543 * 0x00000021);
+  printf("%08x\n", -(int)0xffffb975 * 0x00000031);
+  printf("%08x\n", -(int)0xffffdb97 * 0x00000531);
 
-  printf("%08x\n", 0x1234 * -0x56);
-  printf("%08x\n", 0x6543 * -0x21);
-  printf("%08x\n", (int)0xffffb975 * -0x31);
-  printf("%08x\n", (int)0xffffdb97 * -0x531);
+  printf("%08x\n", 0x00001234 * -0x00000056);
+  printf("%08x\n", 0x00006543 * -0x00000021);
+  printf("%08x\n", (int)0xffffb975 * -0x00000031);
+  printf("%08x\n", (int)0xffffdb97 * -0x00000531);
 
-  printf("%08x\n", -0x1234 * -0x56);
-  printf("%08x\n", -0x6543 * -0x21);
-  printf("%08x\n", -(int)0xffffb975 * -0x31);
-  printf("%08x\n", -(int)0xffffdb97 * -0x531);
+  printf("%08x\n", -0x00001234 * -0x00000056);
+  printf("%08x\n", -0x00006543 * -0x00000021);
+  printf("%08x\n", -(int)0xffffb975 * -0x00000031);
+  printf("%08x\n", -(int)0xffffdb97 * -0x00000531);
+
+  printf("%016lx\n", 0x000000001357db97L * 0x00000000fdb97531L);
+  printf("%016lx\n", 0x000000001357db97L * 0xfffffffffdb97531L);
+  printf("%016lx\n", ~0x000000001357db97L * 0xfffffffffdb97531L);
+  printf("%016lx\n", 0x000000001357db97L * ~0xfffffffffdb97531L);
+  printf("%016lx\n", ~0x000000001357db97L * ~0xfffffffffdb97531L);
 
   return 0;
 }
diff --git a/mul2.c b/mul2.c
deleted file mode 100644
index ca9f5ad..0000000
--- a/mul2.c
+++ /dev/null
@@ -1,30 +0,0 @@
-#include <stdio.h>
-
-int main(void) {
-  printf("%08x\n", (unsigned short)0x1234 * (unsigned short)0x56);
-  printf("%08x\n", (unsigned short)0x6543 * (unsigned short)0x21);
-  printf("%08x\n", (unsigned short)0xb975 * (unsigned short)0x31);
-  printf("%08x\n", (unsigned short)0xdb97 * (unsigned short)0x531);
-
-  printf("%08x\n", (unsigned short)0x1234 * (unsigned short)0x56);
-  printf("%08x\n", (unsigned short)0x6543 * (unsigned short)0x21);
-  printf("%08x\n", (unsigned short)(int)0xffffb975 * (unsigned short)0x31);
-  printf("%08x\n", (unsigned short)(int)0xffffdb97 * (unsigned short)0x531);
-
-  printf("%08x\n", (unsigned short)-0x1234 * (unsigned short)0x56);
-  printf("%08x\n", (unsigned short)-0x6543 * (unsigned short)0x21);
-  printf("%08x\n", (unsigned short)-(int)0xffffb975 * (unsigned short)0x31);
-  printf("%08x\n", (unsigned short)-(int)0xffffdb97 * (unsigned short)0x531);
-
-  printf("%08x\n", (unsigned short)0x1234 * (unsigned short)-0x56);
-  printf("%08x\n", (unsigned short)0x6543 * (unsigned short)-0x21);
-  printf("%08x\n", (unsigned short)(int)0xffffb975 * (unsigned short)-0x31);
-  printf("%08x\n", (unsigned short)(int)0xffffdb97 * (unsigned short)-0x531);
-
-  printf("%08x\n", (unsigned short)-0x1234 * (unsigned short)-0x56);
-  printf("%08x\n", (unsigned short)-0x6543 * (unsigned short)-0x21);
-  printf("%08x\n", (unsigned short)-(int)0xffffb975 * (unsigned short)-0x31);
-  printf("%08x\n", (unsigned short)-(int)0xffffdb97 * (unsigned short)-0x531);
-
-  return 0;
-}
diff --git a/sm3.asm b/sm3.asm
index 22bd08f..584108b 100644
--- a/sm3.asm
+++ b/sm3.asm
@@ -1,6 +1,6 @@
-page0	=	3
-page1	=	5
-page2	=	7
+page0	=	4
+page1	=	6
+page2	=	8
 
 	.area	SM (abs,ovr)
 
@@ -10,101 +10,196 @@ page2	=	7
 	ld	de,0x56
 	call	math_mul_uw0
 	call	print_hlde
+	call	math_div_uw
+	call	print_hlde
 
 	ld	hl,0x6543
 	ld	de,0x21
 	call	math_mul_uw0
 	call	print_hlde
+	call	math_div_uw
+	call	print_hlde
 
 	ld	hl,0xb975
 	ld	de,0x31
 	call	math_mul_uw0
 	call	print_hlde
+	call	math_div_uw
+	call	print_hlde
 
 	ld	hl,0xdb97
 	ld	de,0x531
 	call	math_mul_uw0
 	call	print_hlde
+	call	math_div_uw
+	call	print_hlde
 
 	ld	hl,0x1234
 	ld	de,0x56
 	call	math_mul_sw0
 	call	print_hlde
+	call	math_div_sw
+	call	print_hlde
 
 	ld	hl,0x6543
 	ld	de,0x21
 	call	math_mul_sw0
 	call	print_hlde
+	call	math_div_sw
+	call	print_hlde
 
 	ld	hl,0xb975
 	ld	de,0x31
 	call	math_mul_sw0
 	call	print_hlde
+	call	math_div_sw
+	call	print_hlde
 
 	ld	hl,0xdb97
 	ld	de,0x531
 	call	math_mul_sw0
 	call	print_hlde
+	call	math_div_sw
+	call	print_hlde
 
 	ld	hl,-0x1234
 	ld	de,0x56
 	call	math_mul_sw0
 	call	print_hlde
+	call	math_div_sw
+	call	print_hlde
 
 	ld	hl,-0x6543
 	ld	de,0x21
 	call	math_mul_sw0
 	call	print_hlde
+	call	math_div_sw
+	call	print_hlde
 
 	ld	hl,-0xb975
 	ld	de,0x31
 	call	math_mul_sw0
 	call	print_hlde
+	call	math_div_sw
+	call	print_hlde
 
 	ld	hl,-0xdb97
 	ld	de,0x531
 	call	math_mul_sw0
 	call	print_hlde
+	call	math_div_sw
+	call	print_hlde
 
 	ld	hl,0x1234
 	ld	de,-0x56
 	call	math_mul_sw0
 	call	print_hlde
+	call	math_div_sw
+	call	print_hlde
 
 	ld	hl,0x6543
 	ld	de,-0x21
 	call	math_mul_sw0
 	call	print_hlde
+	call	math_div_sw
+	call	print_hlde
 
 	ld	hl,0xb975
 	ld	de,-0x31
 	call	math_mul_sw0
 	call	print_hlde
+	call	math_div_sw
+	call	print_hlde
 
 	ld	hl,0xdb97
 	ld	de,-0x531
 	call	math_mul_sw0
 	call	print_hlde
+	call	math_div_sw
+	call	print_hlde
 
 	ld	hl,-0x1234
 	ld	de,-0x56
 	call	math_mul_sw0
 	call	print_hlde
+	call	math_div_sw
+	call	print_hlde
 
 	ld	hl,-0x6543
 	ld	de,-0x21
 	call	math_mul_sw0
 	call	print_hlde
+	call	math_div_sw
+	call	print_hlde
 
 	ld	hl,-0xb975
 	ld	de,-0x31
 	call	math_mul_sw0
 	call	print_hlde
+	call	math_div_sw
+	call	print_hlde
 
 	ld	hl,-0xdb97
 	ld	de,-0x531
 	call	math_mul_sw0
 	call	print_hlde
+	call	math_div_sw
+	call	print_hlde
+
+	ld	hl,0xdb97
+	ld	de,0x7531
+	exx
+	ld	hl,0x1357
+	ld	de,0xfdb9
+	exx
+	call	math_mul_ul0
+	call	print_hlhldede
+	call	math_div_ul
+	call	print_hlhldede
+
+	ld	hl,0xdb97
+	ld	de,0x7531
+	exx
+	ld	hl,0x1357
+	ld	de,0xfdb9
+	exx
+	call	math_mul_sl0
+	call	print_hlhldede
+	call	math_div_sl
+	call	print_hlhldede
+
+	ld	hl,~0xdb97
+	ld	de,0x7531
+	exx
+	ld	hl,~0x1357
+	ld	de,0xfdb9
+	exx
+	call	math_mul_sl0
+	call	print_hlhldede
+	call	math_div_sl
+	call	print_hlhldede
+
+	ld	hl,0xdb97
+	ld	de,~0x7531
+	exx
+	ld	hl,0x1357
+	ld	de,~0xfdb9
+	exx
+	call	math_mul_sl0
+	call	print_hlhldede
+	call	math_div_sl
+	call	print_hlhldede
+
+	ld	hl,~0xdb97
+	ld	de,~0x7531
+	exx
+	ld	hl,~0x1357
+	ld	de,~0xfdb9
+	exx
+	call	math_mul_sl0
+	call	print_hlhldede
+	call	math_div_sl
+	call	print_hlhldede
 
 	ld	hl,restarts
 	ld	de,0x28
@@ -832,7 +927,7 @@ page2_imm_divrev_sl:
 	;.db	0x3e ; ld a,
 	ex	de,hl
 	push	bc
-	call	math_div_sl1
+	call	math_sdiv_sl
 	jr	div_l_done
 page2_div_sl:
 	;rst	0x30
@@ -842,14 +937,14 @@ page2_div_sl:
 	exx
 	ex	de,hl
 	push	bc
-	call	math_div_sl1
+	call	math_sdiv_sl
 	jr	div_l_done
 
 page2_imm_div_sl:
 	rst	0x38
 	;.db	0x3e ; ld a,
 	push	bc
-	call	math_div_sl0
+	call	math_sdiv_sl0
 	jr	div_l_done
 page2_divrev_sl:
 	;rst	0x30
@@ -858,7 +953,7 @@ page2_divrev_sl:
 	pop	de
 	exx
 	push	bc
-	call	math_div_sl0
+	call	math_sdiv_sl0
 	jr	div_l_done
 
 page2_imm_divrev_ul:
@@ -1947,6 +2042,7 @@ math_mul_uw0: ; hl:de = hl * de, unsigned
 math_mul_uw: ; hl:de = hl + bc * de, unsigned
 	ld	a,e
 	call	mul_uw
+	ld	e,a
 	ld	a,d
 	call	mul_uw
 	ld	d,a
@@ -2004,6 +2100,208 @@ mul_uw1:
 	rra
 	ret
 
+math_mul_sl0: ; hl':hl:de':de = hl':hl * de':de, signed
+	ld	c,l
+	ld	b,h
+	sub	a
+	ld	l,a
+	ld	h,a
+	exx
+	ld	c,l
+	ld	b,h
+	ld	l,a
+	ld	h,a
+	exx ; hard to optimize this
+math_mul_sl: ; hl':hl:de':de = hl':hl + bc':bc * de':de, signed
+	exx
+	ld	a,b
+	rla ; cf will be preserved through to the last rra below
+	exx
+	ld	a,e
+	call	mul_ul
+	push	af
+	ld	a,d
+	call	mul_ul
+	push	af
+	exx
+	ld	a,e
+	exx
+	call	mul_ul
+	push	af
+	exx
+	ld	a,d
+	exx
+	call	mul_ul1 ; do only 7 bits, get sign of d into cf
+	jr	nc,1$
+	or	a
+	sbc	hl,bc
+	exx
+	sbc	hl,bc
+	exx ; hard to optimize this
+1$:	exx
+	rr	h
+	rr	l
+	exx
+	rr	h
+	rr	l
+	rra
+	jr	nc,2$
+	or	a
+	sbc	hl,de
+	exx
+	sbc	hl,de
+	exx ; hard to optimize this
+2$:	exx
+	ld	d,a
+	pop	af
+	ld	e,a
+	exx
+	pop	de
+	pop	af
+	ld	e,a
+	ret
+
+math_mul_ul0: ; hl':hl:de':de = hl':hl * de':de, unsigned
+	ld	c,l
+	ld	b,h
+	sub	a
+	ld	l,a
+	ld	h,a
+	exx
+	ld	c,l
+	ld	b,h
+	ld	l,a
+	ld	h,a
+	exx
+math_mul_ul: ; hl':hl:de':de = hl':hl + bc':bc * de':de, unsigned
+	ld	a,e
+	call	mul_ul
+	ld	e,a
+	ld	a,d
+	call	mul_ul
+	ld	d,a
+	exx
+	ld	a,e
+	exx
+	call	mul_ul
+	exx
+	ld	e,a
+	ld	a,d
+	exx
+	call	mul_ul
+	exx
+	ld	d,a
+	exx
+	ret
+
+mul_ul: rra
+	; bit 0
+	jr	nc,1$
+	add	hl,bc
+	exx
+	adc	hl,bc
+	exx ; optimize this
+1$:	exx
+	rr	h
+	rr	l
+	exx
+	rr	h
+	rr	l
+mul_ul1:
+	rra
+	; bit 1
+	jr	nc,2$
+	add	hl,bc
+	exx
+	adc	hl,bc
+	exx ; optimize this
+2$:	exx
+	rr	h
+	rr	l
+	exx
+	rr	h
+	rr	l
+	rra
+	; bit 2
+	jr	nc,3$
+	add	hl,bc
+	exx
+	adc	hl,bc
+	exx ; optimize this
+3$:	exx
+	rr	h
+	rr	l
+	exx
+	rr	h
+	rr	l
+	rra
+	; bit 3
+	jr	nc,4$
+	add	hl,bc
+	exx
+	adc	hl,bc
+	exx ; optimize this
+4$:	exx
+	rr	h
+	rr	l
+	exx
+	rr	h
+	rr	l
+	rra
+	; bit 4
+	jr	nc,5$
+	add	hl,bc
+	exx
+	adc	hl,bc
+	exx ; optimize this
+5$:	exx
+	rr	h
+	rr	l
+	exx
+	rr	h
+	rr	l
+	rra
+	; bit 5
+	jr	nc,6$
+	add	hl,bc
+	exx
+	adc	hl,bc
+	exx ; optimize this
+6$:	exx
+	rr	h
+	rr	l
+	exx
+	rr	h
+	rr	l
+	rra
+	; bit 6	
+	jr	nc,7$
+	add	hl,bc
+	exx
+	adc	hl,bc
+	exx ; optimize this
+7$:	exx
+	rr	h
+	rr	l
+	exx
+	rr	h
+	rr	l
+	rra
+	; bit 7
+	jr	nc,8$
+	add	hl,bc
+	exx
+	adc	hl,bc
+	exx ; optimize this
+8$:	exx
+	rr	h
+	rr	l
+	exx
+	rr	h
+	rr	l
+	rra
+	ret
+
 ; sdiv: short division
 ; 16 / 16 to 16 bit quotient, 16 bit remainder (word)
 ; 32 / 32 to 32 bit quotient, 32 bit remainder (long)
@@ -2081,6 +2379,17 @@ math_sdiv_uw: ; hl, de = de % hl, de / hl, unsigned
 	ld	b,h
 	ld	hl,0
 math_div_uw: ; hl, de = hl:de % bc, hl:de / bc, unsigned
+ ld a,'X
+ call print_char
+ call print_word
+ ex de,hl
+ call print_word
+ ex de,hl
+ push hl
+ ld l,c
+ ld h,b
+ call print_word
+ pop hl
 	ld	a,d
 div_w_pp: ; positive dividend, positive divisor
 	call	div_w0
@@ -2234,7 +2543,7 @@ div_w07: ; bit 7, above
 div_w18: ; done, below
 	add	a,a
 	;inc	a
-	;bcc	a			; compensation
+	;dec	a			; compensation
 	scf
 	ret
 
@@ -2360,15 +2669,15 @@ div_w_n07: ; bit 7, above
 div_w_n18: ; done, below
 	add	a,a
 	;inc	a
-	;bcc	a			; compensation
+	;dec	a			; compensation
 	scf
 	ret
 
-math_div_sl0: ; hl':hl, de':de = hl':de % de':hl, hl':de / de':hl, signed
+math_sdiv_sl0: ; hl':hl, de':de = hl':de % de':hl, hl':de / de':hl, signed
 	exx
 	ex	de,hl
 	exx
-math_div_sl1: ; ; hl':hl, de':de = de':de % hl':hl, de':de / hl':hl, signed
+math_sdiv_sl: ; ; hl':hl, de':de = de':de % hl':hl, de':de / hl':hl, signed
 	exx
 	ld	c,l
 	ld	b,h
@@ -2482,11 +2791,11 @@ math_div_ul1: ; ; hl':hl, de':de = de':de % hl':hl, de':de / hl':hl, unsigned
 	ld	b,h
 	ld	l,a
 	ld	h,a
-	;exx
-;math_div_ul:
+	exx
+math_div_ul:
 	; hl':hl, de':de =
 	;   hl':hl:de':de % bc':bc, hl':hl:de':de / bc':bc, unsigned
-	;exx
+	exx
 	ld	a,d
 	exx
 div_l_pp: ; positive dividend, positive divisor
@@ -2988,6 +3297,26 @@ print_hlde:
 	ld	a,0xa
 	jp	print_char
 
+print_hlhldede:
+	exx
+	call	print_word
+	exx
+	call	print_word
+	ld	a,':
+	call	print_char
+	exx
+	ex	de,hl
+	call	print_word
+	ex	de,hl
+	exx
+	ex	de,hl
+	call	print_word
+	ex	de,hl
+	ld	a,0xd
+	call	print_char
+	ld	a,0xa
+	jp	print_char
+
 print_trace: ; print af, bc, hl':de, de':hl, (sp+2):(sp), sp
 	call	print_trace2
 	ld	a,(bc)
-- 
2.34.1