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zasm: generalize handling of IX/IY in 0xcb upcode family
There's a couple of bit fiddling instructions that didn't have their IX/IY variant implemented yet and without this commit, each of them would have required a special routine. Not anymore.
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@ -2,7 +2,7 @@
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; Number of rows in the argspec table
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.equ ARGSPEC_TBL_CNT 33
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; Number of rows in the primary instructions table
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.equ INSTR_TBL_CNT 150
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.equ INSTR_TBL_CNT 144
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; size in bytes of each row in the primary instructions table
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.equ INSTR_TBL_ROWSIZE 6
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; Instruction IDs They correspond to the index of the table in instrNames
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@ -487,28 +487,6 @@ _handleBITR:
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ld c, 2
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ret
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handleBITIXY:
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ld b, 0b01000110
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jr _handleBITIXY
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handleSETIXY:
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ld b, 0b11000110
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jr _handleBITIXY
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handleRESIXY:
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ld b, 0b10000110
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_handleBITIXY:
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ld a, 0xcb ; 1st upcode
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ld (INS_UPCODE), a
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ld a, (INS_CURARG2+1) ; IXY displacement
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ld (INS_UPCODE+1), a
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ld a, (INS_CURARG1+1) ; 0-7
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rlca ; clears cary if any
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rla
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rla
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or b ; 4th upcode
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ld (INS_UPCODE+2), a
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ld c, 3
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ret
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handleIM:
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ld a, (INS_CURARG1+1)
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cp 0
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@ -798,6 +776,11 @@ spitUpcode:
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inc c
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; to writeIO
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.writeIO:
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; Before we write IO, let's check a very specific case: is our first
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; upcode 0xcb and our byte count == 3? If yes, then swap the two last
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; bytes. In all instructions except 0xcb ones, IX/IY displacement comes
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; last, but in all 0xcb instructions, they come 2nd last.
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call .checkCB
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; Let's write INS_UPCODE to IO
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dec c \ inc c ; is C zero?
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jr z, .numberTruncated
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@ -825,6 +808,21 @@ spitUpcode:
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pop de
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pop ix
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ret
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.checkCB:
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ld a, (INS_UPCODE)
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cp 0xcb
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ret nz
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ld a, c
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cp 3
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ret nz
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; We are in 0xcb + displacement situation. Swap bytes 2 and 3.
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ld a, (INS_UPCODE+1)
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ex af, af'
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ld a, (INS_UPCODE+2)
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ld (INS_UPCODE+1), a
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ex af, af'
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ld (INS_UPCODE+2), a
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ret
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; Parse argument in (HL) and place it in (DE)
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; Sets Z on success, reset on error.
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@ -1082,9 +1080,7 @@ instrTBl:
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.db I_AND, 'l', 0, 0x10, 0xa6 , 0 ; AND (HL) + (IX/Y)
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.db I_AND, 0xb, 0, 0, 0b10100000 , 0 ; AND r
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.db I_AND, 'n', 0, 0, 0xe6 , 0 ; AND n
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.db I_BIT, 0xc, 'x', 0x20 \ .dw handleBITIXY ; BIT b, (IX+d)
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.db I_BIT, 0xc, 'y', 0x20 \ .dw handleBITIXY ; BIT b, (IY+d)
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.db I_BIT, 0xc, 'l', 0x43, 0xcb, 0b01000110 ; BIT b, (HL)
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.db I_BIT, 0xc, 'l', 0x53, 0xcb, 0b01000110 ; BIT b, (HL) + (IX/Y)
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.db I_BIT, 'n', 0xb, 0x20 \ .dw handleBITR ; BIT b, r
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.db I_CALL,0xa, 'N', 3, 0b11000100 , 0 ; CALL cc, NN
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.db I_CALL,'N', 0, 0, 0xcd , 0 ; CALL NN
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@ -1187,8 +1183,6 @@ instrTBl:
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.db I_PUSH,'X', 0, 0, 0xdd, 0xe5 ; PUSH IX
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.db I_PUSH,'Y', 0, 0, 0xfd, 0xe5 ; PUSH IY
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.db I_PUSH,0x1, 0, 4, 0b11000101 , 0 ; PUSH qq
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.db I_RES, 0xc, 'x', 0x20 \ .dw handleRESIXY ; RES b, (IX+d)
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.db I_RES, 0xc, 'y', 0x20 \ .dw handleRESIXY ; RES b, (IY+d)
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.db I_RES, 0xc, 'l', 0x53, 0xcb, 0b10000110 ; RES b, (HL) + (IX/Y)
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.db I_RES, 'n', 0xb, 0x20 \ .dw handleRESR ; RES b, r
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.db I_RET, 0, 0, 0, 0xc9 , 0 ; RET
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@ -1207,8 +1201,6 @@ instrTBl:
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.db I_SBC, 'A', 0xb, 0, 0b10011000 , 0 ; SBC A, r
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.db I_SBC,'h',0x3,0x44, 0xed, 0b01000010 ; SBC HL, ss
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.db I_SCF, 0, 0, 0, 0x37 , 0 ; SCF
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.db I_SET, 0xc, 'x', 0x20 \ .dw handleSETIXY ; SET b, (IX+d)
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.db I_SET, 0xc, 'y', 0x20 \ .dw handleSETIXY ; SET b, (IY+d)
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.db I_SET, 0xc, 'l', 0x53, 0xcb, 0b11000110 ; SET b, (HL) + (IX/Y)
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.db I_SET, 'n', 0xb, 0x20 \ .dw handleSETR ; SET b, r
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.db I_SLA, 0xb, 0,0x40, 0xcb, 0b00100000 ; SLA r
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@ -101,7 +101,7 @@ testSpitUpcode:
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; Test data is a argspec pointer in instrTBl followed by 2*3 bytes of CURARG
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; followed by the expected spit, 1 byte cnt + 4 bytes spits.
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.t1:
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.dw instrTBl+19*6 ; CCF
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.dw instrTBl+17*6 ; CCF
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.db 0, 0, 0
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.db 0, 0, 0
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.db 1, 0x3f, 0, 0, 0
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@ -116,7 +116,7 @@ testSpitUpcode:
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.db 'x', 3, 0
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.db 4, 0xdd, 0xcb, 0x03, 0x66
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.t4:
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.dw instrTBl+20*6 ; CP (IX+5)
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.dw instrTBl+18*6 ; CP (IX+5)
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.db 'x', 5, 0
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.db 0, 0, 0
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.db 3, 0xdd, 0xbe, 0x05, 0
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