155 lines
6.1 KiB
Plaintext
155 lines
6.1 KiB
Plaintext
This chapter documents the backend for the 8080/z80/gbz80/64180/RCMx000
|
|
microprocessor family.
|
|
|
|
@section Legal
|
|
|
|
This module is copyright in 2009 by Dominic Morris.
|
|
|
|
@example
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
|
|
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
|
|
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
|
|
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
|
|
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
|
|
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
|
|
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
|
|
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
|
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
|
|
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
|
@end example
|
|
|
|
|
|
@section Additional options for this module
|
|
|
|
This module provides the following additional options:
|
|
|
|
@table @option
|
|
@item -8080
|
|
Turns on 8080 compatibility mode. Any use of z80 (or higher)
|
|
opcodes will result in an error being generated.
|
|
@item -gbz80
|
|
Turns on gbz80 compatibility mode. Any use of non-supported
|
|
opcodes will result in an error being generated.
|
|
@item -hd64180
|
|
Turns on 64180 mode supporting additional 64180 opcodes.
|
|
@item -rcm2000
|
|
@item -rcm3000
|
|
@item -rcm4000
|
|
Turns on Rabbit compatibility mode, generating the correct
|
|
codes for moved opcodes and supporting the additional Rabbit
|
|
instructions. In this mode, 8 bit access to the 16 bit index
|
|
registers is not permitted.
|
|
@item -rcmemu
|
|
Turns on emulation of some instructions which aren't available
|
|
on the Rabbit processors.
|
|
@item -swapixiy
|
|
Swaps the usage of ix and iy registers. This is useful
|
|
for compiling generic code that uses an index register that
|
|
is reserved on the target machine.
|
|
@item -z80asm
|
|
Switches on z80asm mode. This translates ASMPC to $ and accepts
|
|
some pseudo opcodes that z80asm supports. Most emulation of
|
|
z80asm directives is provided by the oldsyntax syntax module.
|
|
@end table
|
|
|
|
@section General
|
|
|
|
This backend accepts z80 family instructions in standard
|
|
Zilog syntax. Rabbit opcodes are accepted as defined in the
|
|
publically available reference material from Rabbit Semiconductor,
|
|
with the exception that the @code{ljp} and @code{lcall} opcodes need
|
|
to be supplied with a 24 bit number rather than an 8 bit @code{xpc} and a
|
|
16 bit address.
|
|
|
|
The target address type is 16 bit.
|
|
|
|
Instructions consist of one up to six bytes and require no alignment.
|
|
There is also no alignment requirement for sections and data.
|
|
|
|
@section Extensions
|
|
|
|
This backend provides the following specific extensions:
|
|
|
|
@itemize @minus
|
|
|
|
@item Certain Rabbit opcodes can be prefixed by the @code{altd} and/or the
|
|
@code{ioi}/@code{ioe} modifier.
|
|
For details of which instructions these are valid for please
|
|
see the documentation from Rabbit.
|
|
|
|
@item The parser understands a lo/hi-modifier to select low- or high-byte
|
|
of a 16-bit word. The character @code{<} is used to select the low-byte
|
|
and @code{>} for the high-byte. It has to be the first character before
|
|
an expression.
|
|
|
|
@item When applying the operation @code{/256}, @code{%256} or @code{&256}
|
|
on a label, an appropriate lo/hi-byte relocation will automatically be
|
|
generated.
|
|
|
|
@end itemize
|
|
|
|
@section Optimisations
|
|
|
|
This backend supports the emulation of certain z80 instructions on the
|
|
Rabbit/gbz80 processor. These instructions are @code{rld}, @code{rrd},
|
|
@code{cpi}, @code{cpir}, @code{cpd} and @code{cpdr}.
|
|
The link stage should provide routines with the opcode name prefixed with
|
|
@code{rcmx_} (eg @code{rcmx_rld}) which implements the same functionality.
|
|
Example implementations are available within the z88dk CVS tree.
|
|
|
|
Additionally, for the Rabbit targets the missing call @code{cc}, opcodes
|
|
will be emulated.
|
|
|
|
@section Known Problems
|
|
|
|
Some known problems of this module at the moment:
|
|
|
|
@itemize @minus
|
|
|
|
@item Not all RCM4000 opcodes are supported (@code{llcall}, @code{lljp}
|
|
are not available).
|
|
|
|
@end itemize
|
|
|
|
@section Error Messages
|
|
|
|
This module has the following error messages:
|
|
|
|
@itemize @minus
|
|
@item 2001: index offset out of bounds (%d)
|
|
@item 2002: Opcode not supported by %s (%s)
|
|
@item 2003: Index registers not available on 8080
|
|
@item 2004: out of range for 8 bit expression (%d)
|
|
@item 2005: invalid bit number (%d) should be in range 0..7
|
|
@item 2006: rst value out of range (%d/0x%02x)
|
|
@item 2007: %s value out of range (%d)
|
|
@item 2008: index offset should be a constant
|
|
@item 2009: invalid branch type for jr
|
|
@item 2010: Rabbit target doesn't support rst %d
|
|
@item 2011: Rabbit target doesn't support 8 bit index registers
|
|
@item 2012: z180 target doesn't support 8 bit index registers
|
|
@item 2013: invalid branch type for jre
|
|
@item 2014: Opcode not supported by %s (%s) but it can be emulated (-rcmemu)
|
|
@item 2015: %s specifier is only valid for Rabbit processors
|
|
@item 2016: Only one of ioi and ioe can be specified at a time
|
|
@item 2017: %s specifier is not valid for the opcode %s
|
|
@item 2018: %s specifier redundant for the opcode %s
|
|
@item 2019: %s specifier has no effect on the opcode %s
|
|
@item 2020: Operand value must evaluate to a constant for opcode %s
|
|
@item 2021: Unhandled operand type wanted 0x%x got 0x%x
|
|
@item 2022: Missed matched index registers on %s
|
|
@item 2023: Only out (c),0 is supported for the opcode %s
|
|
@item 2024: Operations between different index registers are forbidden
|
|
@item 2025: Operations between ix/iy/hl are forbidden
|
|
@item 2026: Double indirection forbidden
|
|
@end itemize
|