zasm: support negative displacement for IX/IY

Needed by #30.

apps/zasm/instr.asm

@@ -109,7 +109,7 @@ getInstID:
 	ret
 
 ; Parse the string at (HL) and check if it starts with IX+, IY+, IX- or IY-.
-; Sets Z if yes, unset if no.
+; Sets Z if yes, unset if no. On success, A contains either '+' or '-'.
 parseIXY:
 	push	hl
 	ld	a, (hl)
@@ -180,13 +180,15 @@ parseArg:
 	ld	a, 'N'
 	jr	.end
 .withParens:
+	ld	b, 0		; make sure it doesn't hold '-'
 	ld	c, 'M'		; C holds the argspec type until we reach
 				; .numberInParens
 	; We have parens. First, let's see if we have a (IX+d) type of arg.
 	call	parseIXY
 	jr	nz, .parseNumberInParens	; not I{X,Y}. just parse number.
 	; We have IX+/IY+/IX-/IY-.
-	; note: the "-" part isn't supported yet.
+	; A contains either '+' or '-'. Save it for later, in B.
+	ld	b, a
 	inc	hl	; (HL) now points to X or Y
 	ld	a, (hl)
 	call	upcase
@@ -202,6 +204,22 @@ parseArg:
 	call	.maybeParseExpr
 	jr	nz, .nomatch
 	; We have a proper number in parens. Number in IX
+	; is '-' in B? if yes, we need to negate the low part of IX
+	ld	a, b
+	cp	'-'
+	jr	nz, .dontNegateIX
+	; we need to negate the low part of IX
+	; TODO: when parsing routines properly support unary negative numbers,
+	; We could replace this complicated scheme below with a nice hack where
+	; we start parsing our displacement number at the '+' and '-' char.
+
+	; HL isn't needed anymore and can be destroyed.
+	push	ix \ pop hl
+	ld	a, l
+	neg
+	ld	l, a
+	push	hl \ pop ix
+.dontNegateIX:
 	ld	a, c	; M, x, or y
 	jr	.end
 .nomatch:

tools/tests/zasm/allinstrs.asm

@@ -48,14 +48,22 @@ ADD IY, IY
 ADD IY, SP
 ADD A, (IX)
 ADD A, (IX+1)
+ADD A, (IX-1)
 ADD A, (IX+10)
+ADD A, (IX-10)
 ADD A, (IX+100)
+ADD A, (IX-100)
 ADD A, (IX+127)
+ADD A, (IX-127)
 ADD A, (IY)
 ADD A, (IY+1)
+ADD A, (IY-1)
 ADD A, (IY+10)
+ADD A, (IY-10)
 ADD A, (IY+100)
+ADD A, (IY-100)
 ADD A, (IY+127)
+ADD A, (IY-127)
 AND (HL)
 AND B
 AND C
@@ -73,46 +81,78 @@ AND 32
 AND 64
 AND 128
 AND (IX+1)
+AND (IX-1)
 AND (IX+10)
+AND (IX-10)
 AND (IX+100)
+AND (IX-100)
 AND (IX+127)
+AND (IX-127)
 AND (IY+1)
+AND (IY-1)
 AND (IY+10)
+AND (IY-10)
 AND (IY+100)
+AND (IY-100)
 AND (IY+127)
+AND (IY-127)
 BIT 1, (HL)
 BIT 2, (HL)
 BIT 4, (HL)
 BIT 1, (IX)
 BIT 1, (IX+1)
+BIT 1, (IX-1)
 BIT 1, (IX+10)
+BIT 1, (IX-10)
 BIT 1, (IX+100)
+BIT 1, (IX-100)
 BIT 1, (IX+127)
+BIT 1, (IX-127)
 BIT 2, (IX)
 BIT 2, (IX+1)
+BIT 2, (IX-1)
 BIT 2, (IX+10)
+BIT 2, (IX-10)
 BIT 2, (IX+100)
+BIT 2, (IX-100)
 BIT 2, (IX+127)
+BIT 2, (IX-127)
 BIT 4, (IX)
 BIT 4, (IX+1)
+BIT 4, (IX-1)
 BIT 4, (IX+10)
+BIT 4, (IX-10)
 BIT 4, (IX+100)
+BIT 4, (IX-100)
 BIT 4, (IX+127)
+BIT 4, (IX-127)
 BIT 1, (IY)
 BIT 1, (IY+1)
+BIT 1, (IY-1)
 BIT 1, (IY+10)
+BIT 1, (IY-10)
 BIT 1, (IY+100)
+BIT 1, (IY-100)
 BIT 1, (IY+127)
+BIT 1, (IY-127)
 BIT 2, (IY)
 BIT 2, (IY+1)
+BIT 2, (IY-1)
 BIT 2, (IY+10)
+BIT 2, (IY-10)
 BIT 2, (IY+100)
+BIT 2, (IY-100)
 BIT 2, (IY+127)
+BIT 2, (IY-127)
 BIT 4, (IY)
 BIT 4, (IY+1)
+BIT 4, (IY-1)
 BIT 4, (IY+10)
+BIT 4, (IY-10)
 BIT 4, (IY+100)
+BIT 4, (IY-100)
 BIT 4, (IY+127)
+BIT 4, (IY-127)
 BIT 1, B
 BIT 1, C
 BIT 1, D
@@ -297,14 +337,22 @@ CP 64
 CP 128
 CP (IX)
 CP (IX+1)
+CP (IX-1)
 CP (IX+10)
+CP (IX-10)
 CP (IX+100)
+CP (IX-100)
 CP (IX+127)
+CP (IX-127)
 CP (IY)
 CP (IY+1)
+CP (IY-1)
 CP (IY+10)
+CP (IY-10)
 CP (IY+100)
+CP (IY-100)
 CP (IY+127)
+CP (IY-127)
 CPD
 CPDR
 CPI
@@ -315,15 +363,23 @@ DEC (HL)
 DEC IX
 DEC (IX)
 DEC (IX+1)
+DEC (IX-1)
 DEC (IX+10)
+DEC (IX-10)
 DEC (IX+100)
+DEC (IX-100)
 DEC (IX+127)
+DEC (IX-127)
 DEC IY
 DEC (IY)
 DEC (IY+1)
+DEC (IY-1)
 DEC (IY+10)
+DEC (IY-10)
 DEC (IY+100)
+DEC (IY-100)
 DEC (IY+127)
+DEC (IY-127)
 DEC B
 DEC C
 DEC D
@@ -380,15 +436,23 @@ INC (HL)
 INC IX
 INC (IX)
 INC (IX+1)
+INC (IX-1)
 INC (IX+10)
+INC (IX-10)
 INC (IX+100)
+INC (IX-100)
 INC (IX+127)
+INC (IX-127)
 INC IY
 INC (IY)
 INC (IY+1)
+INC (IY-1)
 INC (IY+10)
+INC (IY-10)
 INC (IY+100)
+INC (IY-100)
 INC (IY+127)
+INC (IY-127)
 INC B
 INC C
 INC D
@@ -1125,6 +1189,14 @@ LD (IX+1), 16
 LD (IX+1), 32
 LD (IX+1), 64
 LD (IX+1), 128
+LD (IX-1), 1
+LD (IX-1), 2
+LD (IX-1), 4
+LD (IX-1), 8
+LD (IX-1), 16
+LD (IX-1), 32
+LD (IX-1), 64
+LD (IX-1), 128
 LD (IX+10), 1
 LD (IX+10), 2
 LD (IX+10), 4
@@ -1133,6 +1205,14 @@ LD (IX+10), 16
 LD (IX+10), 32
 LD (IX+10), 64
 LD (IX+10), 128
+LD (IX-10), 1
+LD (IX-10), 2
+LD (IX-10), 4
+LD (IX-10), 8
+LD (IX-10), 16
+LD (IX-10), 32
+LD (IX-10), 64
+LD (IX-10), 128
 LD (IX+100), 1
 LD (IX+100), 2
 LD (IX+100), 4
@@ -1141,6 +1221,14 @@ LD (IX+100), 16
 LD (IX+100), 32
 LD (IX+100), 64
 LD (IX+100), 128
+LD (IX-100), 1
+LD (IX-100), 2
+LD (IX-100), 4
+LD (IX-100), 8
+LD (IX-100), 16
+LD (IX-100), 32
+LD (IX-100), 64
+LD (IX-100), 128
 LD (IX+127), 1
 LD (IX+127), 2
 LD (IX+127), 4
@@ -1149,6 +1237,14 @@ LD (IX+127), 16
 LD (IX+127), 32
 LD (IX+127), 64
 LD (IX+127), 128
+LD (IX-127), 1
+LD (IX-127), 2
+LD (IX-127), 4
+LD (IX-127), 8
+LD (IX-127), 16
+LD (IX-127), 32
+LD (IX-127), 64
+LD (IX-127), 128
 LD (IY), 1
 LD (IY), 2
 LD (IY), 4
@@ -1165,6 +1261,14 @@ LD (IY+1), 16
 LD (IY+1), 32
 LD (IY+1), 64
 LD (IY+1), 128
+LD (IY-1), 1
+LD (IY-1), 2
+LD (IY-1), 4
+LD (IY-1), 8
+LD (IY-1), 16
+LD (IY-1), 32
+LD (IY-1), 64
+LD (IY-1), 128
 LD (IY+10), 1
 LD (IY+10), 2
 LD (IY+10), 4
@@ -1173,6 +1277,14 @@ LD (IY+10), 16
 LD (IY+10), 32
 LD (IY+10), 64
 LD (IY+10), 128
+LD (IY-10), 1
+LD (IY-10), 2
+LD (IY-10), 4
+LD (IY-10), 8
+LD (IY-10), 16
+LD (IY-10), 32
+LD (IY-10), 64
+LD (IY-10), 128
 LD (IY+100), 1
 LD (IY+100), 2
 LD (IY+100), 4
@@ -1181,6 +1293,14 @@ LD (IY+100), 16
 LD (IY+100), 32
 LD (IY+100), 64
 LD (IY+100), 128
+LD (IY-100), 1
+LD (IY-100), 2
+LD (IY-100), 4
+LD (IY-100), 8
+LD (IY-100), 16
+LD (IY-100), 32
+LD (IY-100), 64
+LD (IY-100), 128
 LD (IY+127), 1
 LD (IY+127), 2
 LD (IY+127), 4
@@ -1189,6 +1309,14 @@ LD (IY+127), 16
 LD (IY+127), 32
 LD (IY+127), 64
 LD (IY+127), 128
+LD (IY-127), 1
+LD (IY-127), 2
+LD (IY-127), 4
+LD (IY-127), 8
+LD (IY-127), 16
+LD (IY-127), 32
+LD (IY-127), 64
+LD (IY-127), 128
 LD (IX), B
 LD (IX), C
 LD (IX), D
@@ -1203,6 +1331,13 @@ LD (IX+1), E
 LD (IX+1), H
 LD (IX+1), L
 LD (IX+1), A
+LD (IX-1), B
+LD (IX-1), C
+LD (IX-1), D
+LD (IX-1), E
+LD (IX-1), H
+LD (IX-1), L
+LD (IX-1), A
 LD (IX+10), B
 LD (IX+10), C
 LD (IX+10), D
@@ -1210,6 +1345,13 @@ LD (IX+10), E
 LD (IX+10), H
 LD (IX+10), L
 LD (IX+10), A
+LD (IX-10), B
+LD (IX-10), C
+LD (IX-10), D
+LD (IX-10), E
+LD (IX-10), H
+LD (IX-10), L
+LD (IX-10), A
 LD (IX+100), B
 LD (IX+100), C
 LD (IX+100), D
@@ -1217,6 +1359,13 @@ LD (IX+100), E
 LD (IX+100), H
 LD (IX+100), L
 LD (IX+100), A
+LD (IX-100), B
+LD (IX-100), C
+LD (IX-100), D
+LD (IX-100), E
+LD (IX-100), H
+LD (IX-100), L
+LD (IX-100), A
 LD (IX+127), B
 LD (IX+127), C
 LD (IX+127), D
@@ -1224,6 +1373,13 @@ LD (IX+127), E
 LD (IX+127), H
 LD (IX+127), L
 LD (IX+127), A
+LD (IX-127), B
+LD (IX-127), C
+LD (IX-127), D
+LD (IX-127), E
+LD (IX-127), H
+LD (IX-127), L
+LD (IX-127), A
 LD (IY), B
 LD (IY), C
 LD (IY), D
@@ -1238,6 +1394,13 @@ LD (IY+1), E
 LD (IY+1), H
 LD (IY+1), L
 LD (IY+1), A
+LD (IY-1), B
+LD (IY-1), C
+LD (IY-1), D
+LD (IY-1), E
+LD (IY-1), H
+LD (IY-1), L
+LD (IY-1), A
 LD (IY+10), B
 LD (IY+10), C
 LD (IY+10), D
@@ -1245,6 +1408,13 @@ LD (IY+10), E
 LD (IY+10), H
 LD (IY+10), L
 LD (IY+10), A
+LD (IY-10), B
+LD (IY-10), C
+LD (IY-10), D
+LD (IY-10), E
+LD (IY-10), H
+LD (IY-10), L
+LD (IY-10), A
 LD (IY+100), B
 LD (IY+100), C
 LD (IY+100), D
@@ -1252,6 +1422,13 @@ LD (IY+100), E
 LD (IY+100), H
 LD (IY+100), L
 LD (IY+100), A
+LD (IY-100), B
+LD (IY-100), C
+LD (IY-100), D
+LD (IY-100), E
+LD (IY-100), H
+LD (IY-100), L
+LD (IY-100), A
 LD (IY+127), B
 LD (IY+127), C
 LD (IY+127), D
@@ -1259,76 +1436,139 @@ LD (IY+127), E
 LD (IY+127), H
 LD (IY+127), L
 LD (IY+127), A
+LD (IY-127), B
+LD (IY-127), C
+LD (IY-127), D
+LD (IY-127), E
+LD (IY-127), H
+LD (IY-127), L
+LD (IY-127), A
 LD B, (IX)
 LD B, (IX+1)
+LD B, (IX-1)
 LD B, (IX+10)
+LD B, (IX-10)
 LD B, (IX+100)
+LD B, (IX-100)
 LD B, (IX+127)
+LD B, (IX-127)
 LD C, (IX)
 LD C, (IX+1)
+LD C, (IX-1)
 LD C, (IX+10)
+LD C, (IX-10)
 LD C, (IX+100)
+LD C, (IX-100)
 LD C, (IX+127)
+LD C, (IX-127)
 LD D, (IX)
 LD D, (IX+1)
+LD D, (IX-1)
 LD D, (IX+10)
+LD D, (IX-10)
 LD D, (IX+100)
+LD D, (IX-100)
 LD D, (IX+127)
+LD D, (IX-127)
 LD E, (IX)
 LD E, (IX+1)
+LD E, (IX-1)
 LD E, (IX+10)
+LD E, (IX-10)
 LD E, (IX+100)
+LD E, (IX-100)
 LD E, (IX+127)
+LD E, (IX-127)
 LD H, (IX)
 LD H, (IX+1)
+LD H, (IX-1)
 LD H, (IX+10)
+LD H, (IX-10)
 LD H, (IX+100)
+LD H, (IX-100)
 LD H, (IX+127)
+LD H, (IX-127)
 LD L, (IX)
 LD L, (IX+1)
+LD L, (IX-1)
 LD L, (IX+10)
+LD L, (IX-10)
 LD L, (IX+100)
+LD L, (IX-100)
 LD L, (IX+127)
+LD L, (IX-127)
 LD A, (IX)
 LD A, (IX+1)
+LD A, (IX-1)
 LD A, (IX+10)
+LD A, (IX-10)
 LD A, (IX+100)
+LD A, (IX-100)
 LD A, (IX+127)
+LD A, (IX-127)
 LD B, (IY)
 LD B, (IY+1)
+LD B, (IY-1)
 LD B, (IY+10)
+LD B, (IY-10)
 LD B, (IY+100)
+LD B, (IY-100)
 LD B, (IY+127)
+LD B, (IY-127)
 LD C, (IY)
 LD C, (IY+1)
+LD C, (IY-1)
 LD C, (IY+10)
+LD C, (IY-10)
 LD C, (IY+100)
+LD C, (IY-100)
 LD C, (IY+127)
+LD C, (IY-127)
 LD D, (IY)
 LD D, (IY+1)
+LD D, (IY-1)
 LD D, (IY+10)
+LD D, (IY-10)
 LD D, (IY+100)
+LD D, (IY-100)
 LD D, (IY+127)
+LD D, (IY-127)
 LD E, (IY)
 LD E, (IY+1)
+LD E, (IY-1)
 LD E, (IY+10)
+LD E, (IY-10)
 LD E, (IY+100)
+LD E, (IY-100)
 LD E, (IY+127)
+LD E, (IY-127)
 LD H, (IY)
 LD H, (IY+1)
+LD H, (IY-1)
 LD H, (IY+10)
+LD H, (IY-10)
 LD H, (IY+100)
+LD H, (IY-100)
 LD H, (IY+127)
+LD H, (IY-127)
 LD L, (IY)
 LD L, (IY+1)
+LD L, (IY-1)
 LD L, (IY+10)
+LD L, (IY-10)
 LD L, (IY+100)
+LD L, (IY-100)
 LD L, (IY+127)
+LD L, (IY-127)
 LD A, (IY)
 LD A, (IY+1)
+LD A, (IY-1)
 LD A, (IY+10)
+LD A, (IY-10)
 LD A, (IY+100)
+LD A, (IY-100)
 LD A, (IY+127)
+LD A, (IY-127)
 LDD
 LDDR
 LDI
@@ -1353,14 +1593,22 @@ OR 64
 OR 128
 OR (IX)
 OR (IX+1)
+OR (IX-1)
 OR (IX+10)
+OR (IX-10)
 OR (IX+100)
+OR (IX-100)
 OR (IX+127)
+OR (IX-127)
 OR (IY)
 OR (IY+1)
+OR (IY-1)
 OR (IY+10)
+OR (IY-10)
 OR (IY+100)
+OR (IY-100)
 OR (IY+127)
+OR (IY-127)
 OTDR
 OTIR
 OUT (1), A
@@ -1395,34 +1643,58 @@ RES 2, (HL)
 RES 4, (HL)
 RES 1, (IX)
 RES 1, (IX+1)
+RES 1, (IX-1)
 RES 1, (IX+10)
+RES 1, (IX-10)
 RES 1, (IX+100)
+RES 1, (IX-100)
 RES 1, (IX+127)
+RES 1, (IX-127)
 RES 2, (IX)
 RES 2, (IX+1)
+RES 2, (IX-1)
 RES 2, (IX+10)
+RES 2, (IX-10)
 RES 2, (IX+100)
+RES 2, (IX-100)
 RES 2, (IX+127)
+RES 2, (IX-127)
 RES 4, (IX)
 RES 4, (IX+1)
+RES 4, (IX-1)
 RES 4, (IX+10)
+RES 4, (IX-10)
 RES 4, (IX+100)
+RES 4, (IX-100)
 RES 4, (IX+127)
+RES 4, (IX-127)
 RES 1, (IY)
 RES 1, (IY+1)
+RES 1, (IY-1)
 RES 1, (IY+10)
+RES 1, (IY-10)
 RES 1, (IY+100)
+RES 1, (IY-100)
 RES 1, (IY+127)
+RES 1, (IY-127)
 RES 2, (IY)
 RES 2, (IY+1)
+RES 2, (IY-1)
 RES 2, (IY+10)
+RES 2, (IY-10)
 RES 2, (IY+100)
+RES 2, (IY-100)
 RES 2, (IY+127)
+RES 2, (IY-127)
 RES 4, (IY)
 RES 4, (IY+1)
+RES 4, (IY-1)
 RES 4, (IY+10)
+RES 4, (IY-10)
 RES 4, (IY+100)
+RES 4, (IY-100)
 RES 4, (IY+127)
+RES 4, (IY-127)
 RES 1, B
 RES 1, C
 RES 1, D
@@ -1505,34 +1777,58 @@ SET 2, (HL)
 SET 4, (HL)
 SET 1, (IX)
 SET 1, (IX+1)
+SET 1, (IX-1)
 SET 1, (IX+10)
+SET 1, (IX-10)
 SET 1, (IX+100)
+SET 1, (IX-100)
 SET 1, (IX+127)
+SET 1, (IX-127)
 SET 2, (IX)
 SET 2, (IX+1)
+SET 2, (IX-1)
 SET 2, (IX+10)
+SET 2, (IX-10)
 SET 2, (IX+100)
+SET 2, (IX-100)
 SET 2, (IX+127)
+SET 2, (IX-127)
 SET 4, (IX)
 SET 4, (IX+1)
+SET 4, (IX-1)
 SET 4, (IX+10)
+SET 4, (IX-10)
 SET 4, (IX+100)
+SET 4, (IX-100)
 SET 4, (IX+127)
+SET 4, (IX-127)
 SET 1, (IY)
 SET 1, (IY+1)
+SET 1, (IY-1)
 SET 1, (IY+10)
+SET 1, (IY-10)
 SET 1, (IY+100)
+SET 1, (IY-100)
 SET 1, (IY+127)
+SET 1, (IY-127)
 SET 2, (IY)
 SET 2, (IY+1)
+SET 2, (IY-1)
 SET 2, (IY+10)
+SET 2, (IY-10)
 SET 2, (IY+100)
+SET 2, (IY-100)
 SET 2, (IY+127)
+SET 2, (IY-127)
 SET 4, (IY)
 SET 4, (IY+1)
+SET 4, (IY-1)
 SET 4, (IY+10)
+SET 4, (IY-10)
 SET 4, (IY+100)
+SET 4, (IY-100)
 SET 4, (IY+127)
+SET 4, (IY-127)
 SET 1, B
 SET 1, C
 SET 1, D

tools/tests/zasm/geninstrs.py

@@ -103,7 +103,7 @@ def genargs(argspec):
         argspec = argspec.upper()
         for n in [1, 10, 100, 127]:
             result.append(f"(I{argspec}+{n})")
-        # TODO: support minus
+            result.append(f"(I{argspec}-{n})")
         return result
     if argspec in argspecTbl:
         return [argspecTbl[argspec]]

tools/tests/zasm/test1.asm

@@ -17,7 +17,7 @@ label2: .dw	0x42
 	ld	ix, 1234
 	ld	iy, 2345
 	ld	(ix+1), l
-	ld	l, (ix+1)
+	ld	l, (ix-1)
 	ld	hl, 0x100
 .equ	baz	0x20
 	; accept space before comma