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Merge pull request #3 from robmcmullen/udis_only

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Preliminary support for 0xfdcb and 0xddcb bit operations
This commit is contained in:
Jeff Tranter 2016-02-29 22:09:55 -05:00
commit e0a5e76ed3
2 changed files with 45 additions and 11 deletions
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10
udis.py
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@ -26,6 +26,7 @@ import signal
pcr = 1
und = 2
z80bit = 4
# Functions
@ -181,7 +182,7 @@ while True:
# Handle relative addresses. Indicated by the flag pcr being set.
# Assumes the operand that needs to be PC relative is the last one.
# Note: Code will need changes if more flags are added.
if flags & 1 == pcr:
if flags & pcr:
if op[length-1] < 128:
op[length-1] = address + op[length-1] + length
else:
@ -195,6 +196,13 @@ while True:
elif length == 2:
operand = format.format(op[1])
elif length == 3:
if flags & z80bit:
opcode = (opcode << 16) + op[2]
# reread opcode table for real format string
length, mnemonic, mode, flags = opcodeTable[opcode]
format = addressModeTable[mode]
operand = format.format(op[1])
else:
operand = format.format(op[1], op[2])
elif length == 4:
operand = format.format(op[1], op[2], op[3])

44
z80.py
View File

@ -299,7 +299,6 @@ addressModeTable = {
"z,nn" : "z,${1:02X}{0:02X}",
}
# Op Code Table
# Key is numeric opcode (possibly multiple bytes)
# Value is a list:
@ -880,10 +879,6 @@ opcodeTable = {
0xdd8e : [3, "adc", "indix+d" ],
# The below are a set of instructions that all start with 0xddcb. They
# are not supported yet.
0xddcb : [ 4, "unimplemented", "implied" ],
0xed40 : [ 2, "in", "b,indc" ],
0xed41 : [ 2, "out", "indc,b" ],
0xed42 : [ 2, "sbc", "hl,bc" ],
@ -976,11 +971,42 @@ opcodeTable = {
0xfdb6 : [ 3, "or", "indiy+d" ],
0xfdbe : [ 3, "cp", "indiy+d" ],
# The below are a set of instructions that all start with 0xfdcb. They
# are not supported yet.
0xfdcb : [ 4, "unimplemented", "implied" ],
# Placeholder 2-byte leadins for the 4-byte ix/iy bit instructions fully
# defined below. The z80bit flag triggers a special case in the disassembler
# to look up the 4 byte instruction.
0xddcb : [ 4, "ixbit", "implied", z80bit ],
0xfdcb : [ 4, "iybit", "implied", z80bit ],
}
def extra_opcodes(addr_table, op_table):
# Create all the 0xddcb and 0xfdcb addressing modes. The modes look like [0-7],(i[xy]+*)[,[abcdehl]]?
for index in ['x', 'y']:
for bit in range(8):
k = "%d,indi%s+d" % (bit, index)
v = "%d,(i%s+${0:02X})" % (bit, index)
addr_table[k] = v
for reg in ['a', 'b', 'c', 'd', 'e', 'h', 'l']:
k = "%d,indi%s+d,%s" % (bit, index, reg)
v = "%d,(i%s+${0:02X}),%s" % (bit, index, reg)
addr_table[k] = v
# Create all the 0xddcb and 0xfdcb opcodes. These are all 4 byte opcodes
# where the 3rd byte is a -128 - +127 offset. For the purposes of using
# this table, the 3rd byte will be marked as zero and the disassembler will
# have to insert the real 3rd byte the check of the z80bit special case
for first_byte, x_or_y in [(0xdd, 'x'), (0xfd, 'y')]:
# groups of 8, expand to full 256
mnemonics_8 = ['rlc', 'rrc', 'rl', 'rr', 'sla', 'sra', 'sll', 'sr1'] + ['bit'] * 8 + ['res'] * 8 + ['set'] * 8
mnemonics = [m for mnemonic in mnemonics_8 for m in [mnemonic]*8]
# create all 256 addressing modes, in groups of 64
addrmodes = ['indi%s+d' + a for a in [',b', ',c', ',d', ',e', ',h', ',l', '', ',a']] * 8 + [f % d for d in range(8) for f in ['%d,indi%%s+d'] * 8] + [f % d for d in range(8) for f in ['%d,indi%%s+d' + a for a in [',b', ',c', ',d', ',e', ',h', ',l', '', ',a']]] * 2
for fourth_byte, (instruction, addrmode) in enumerate(zip(mnemonics, addrmodes)):
opcode = (first_byte << 24) + (0xcb << 16) + fourth_byte
op_table[opcode] = [ 4, instruction, addrmode % x_or_y, z80bit ]
extra_opcodes(addressModeTable, opcodeTable)
del extra_opcodes
# End of processor specific code
##########################################################################