273 lines
8.9 KiB
Plaintext
273 lines
8.9 KiB
Plaintext
|
Mixed-Language Source Files
|
|||
|
|
|
|||
|
|
This directory contains mixed-language example programs and macros.
|
|||
|
|
|
|||
|
|
The following source files are the sample programs from Chapter 6,
|
|||
|
|
"Assembly-to-High-Level Interface," of the Mixed-Language Programming
|
|||
|
|
Guide:
|
|||
|
|
|
|||
|
|
BA.ASM Assembly module to be called from BASIC
|
|||
|
|
CA.ASM Assembly module to be called from C
|
|||
|
|
FA.ASM Assembly module to be called from FORTRAN
|
|||
|
|
PA.ASM Assembly module to be called from Pascal
|
|||
|
|
|
|||
|
|
BAMAIN.BAS BASIC main program that calls assembly module
|
|||
|
|
CAMAIN.C C main program that calls assembly module
|
|||
|
|
FAMAIN.FOR FORTRAN main program that calls assembly module
|
|||
|
|
PAMAIN.PAS Pascal main program that calls assembly module
|
|||
|
|
|
|||
|
|
In addition, the directory contains the following files:
|
|||
|
|
|
|||
|
|
MIXED.INC Macros for simplifying assembly routines intended
|
|||
|
|
to be called from high-level languages.
|
|||
|
|
POWER2.ASM Macro version of assembly module that can be called
|
|||
|
|
from BASIC, C, FORTRAN, or Pascal.
|
|||
|
|
|
|||
|
|
Mixed-Language Macros
|
|||
|
|
|
|||
|
|
MIXED.INC contains macros for defining high-level-language routines.
|
|||
|
|
It can create functions for Microsoft C, FORTRAN, or Pascal, and for
|
|||
|
|
future versions of Microsoft BASIC. It can also create subprograms
|
|||
|
|
for BASIC, subroutines for FORTRAN, or procedures for Pascal.
|
|||
|
|
|
|||
|
|
Note: Some BASIC examples use functions and the DECLARE
|
|||
|
|
statement. These features are not available in versions of
|
|||
|
|
Microsoft BASIC available at release time. They will work
|
|||
|
|
if you rewrite functions as subprograms. Functions and
|
|||
|
|
DECLARE statements will be supported in future versions of
|
|||
|
|
Microsoft BASIC compilers.
|
|||
|
|
|
|||
|
|
The following macros are provided:
|
|||
|
|
|
|||
|
|
Macro Purpose
|
|||
|
|
|
|||
|
|
setModel Sets memory model passed from a DOS command line
|
|||
|
|
hProc Initializes a procedure
|
|||
|
|
hLocal Initializes local variables
|
|||
|
|
hRet Returns from a procedure
|
|||
|
|
hEndp Terminates a procedure
|
|||
|
|
|
|||
|
|
ifFP Assembles statement if the memory model uses far data
|
|||
|
|
FP Provides ES override if the memory model uses far data
|
|||
|
|
pLes Loads data (through ES for far data)
|
|||
|
|
pLds Loads data (through DS for far data)
|
|||
|
|
|
|||
|
|
Other internal macros in MIXED.INC are used by these macros, but can
|
|||
|
|
be ignored by the user.
|
|||
|
|
Macro Syntax
|
|||
|
|
|
|||
|
|
The calling convention used in the macros depends on whether the
|
|||
|
|
symbol "cLang" is defined. If "cLang" is defined, the C calling
|
|||
|
|
convention is used. Otherwise, the calling convention used by
|
|||
|
|
BASIC, FORTRAN, and Pascal is used.
|
|||
|
|
|
|||
|
|
Macro names and arguments are case insensitive. The macros and
|
|||
|
|
their syntax are described below:
|
|||
|
|
|
|||
|
|
setModel
|
|||
|
|
|
|||
|
|
Sets the memory model to small, medium, compact, large, or huge.
|
|||
|
|
This macro is an alternative to the .MODEL directive. It enables
|
|||
|
|
you to pass a memory model from the MASM command line. For
|
|||
|
|
example, you can use
|
|||
|
|
|
|||
|
|
setModel
|
|||
|
|
|
|||
|
|
as the first code in your source file and supply the memory model
|
|||
|
|
with the /D option as shown below:
|
|||
|
|
|
|||
|
|
MASM /Dmodel=medium source;
|
|||
|
|
|
|||
|
|
|
|||
|
|
hProc <name [NEAR|FAR]> [,<USES reglist>] [,arg[:type] [,arg[:type]]]...
|
|||
|
|
|
|||
|
|
Initializes a procedure by pushing BP and saving SP in BP. The
|
|||
|
|
macro also handles the following tasks:
|
|||
|
|
|
|||
|
|
1. Declares the procedure name public in the format of the language
|
|||
|
|
("doTask" is declared as "_doTask" for the C compiler).
|
|||
|
|
|
|||
|
|
2. Gives the procedure the type NEAR or FAR if specified, or the
|
|||
|
|
default type for the memory model (NEAR for small and compact
|
|||
|
|
models or FAR for medium, large, and huge models). If type is
|
|||
|
|
specified, the name and type must be enclosed in angle brackets.
|
|||
|
|
|
|||
|
|
3. Saves and restores specified registers. The keyword USES must
|
|||
|
|
be given as a parameter followed by the registers. USES and
|
|||
|
|
the registers must be enclosed in angle brackets.
|
|||
|
|
|
|||
|
|
4. Assigns names and types to stack parameters. The type for
|
|||
|
|
parameters can be BYTE, WORD, DWORD, FWORD, QWORD, TWORD, or
|
|||
|
|
PTR. If no type is given, WORD is assumed. PTR type means
|
|||
|
|
that the parameter is a pointer. It's size is variable
|
|||
|
|
depending on the size of the memory model. Pointers are
|
|||
|
|
assumed to point to data, so the size is NEAR for small and
|
|||
|
|
medium models or FAR for compact, large, and huge models.
|
|||
|
|
|
|||
|
|
For example,
|
|||
|
|
|
|||
|
|
hProc <doTask FAR>, <USES si di>, count:BYTE, array:PTR, number
|
|||
|
|
|
|||
|
|
defines the FAR procedure "doTask" with byte parameter "count",
|
|||
|
|
pointer paramter "array", and word parameter "number". The SI and
|
|||
|
|
DI registers are saved.
|
|||
|
|
|
|||
|
|
hLocal var[:type] [,var[:type]]...
|
|||
|
|
|
|||
|
|
Saves space on the stack for local variables and assign them
|
|||
|
|
variables names. For example,
|
|||
|
|
|
|||
|
|
hLocal work,temp:DWORD
|
|||
|
|
|
|||
|
|
allocates "work" as a temporary word variable and "temp" as a
|
|||
|
|
temporary doubleword variable.
|
|||
|
|
|
|||
|
|
|
|||
|
|
hRet
|
|||
|
|
|
|||
|
|
Returns from a procedure. SP is restored from BP if local variables
|
|||
|
|
have been used. BP is popped. A RET instruction is given in
|
|||
|
|
the format appropriate for the memory model and calling
|
|||
|
|
convention.
|
|||
|
|
|
|||
|
|
|
|||
|
|
hEndp
|
|||
|
|
|
|||
|
|
Ends a procedure. Note that a procedure may have several return
|
|||
|
|
points, but only one end point.
|
|||
|
|
|
|||
|
|
|
|||
|
|
ifFP statement
|
|||
|
|
|
|||
|
|
Assembles the statement if the memory model uses far data. This
|
|||
|
|
macro can be used to push segment registers or take other
|
|||
|
|
action that is only required for far data. For example,
|
|||
|
|
|
|||
|
|
ifFP push ds
|
|||
|
|
|
|||
|
|
pushes the DS register in compact, large, and huge memory
|
|||
|
|
models, but has no effect in small and medium models.
|
|||
|
|
|
|||
|
|
|
|||
|
|
FPoperand
|
|||
|
|
|
|||
|
|
Gives an ES override if the memory model uses far data. In
|
|||
|
|
models that use near data, FP is null. For example,
|
|||
|
|
|
|||
|
|
mov ax,FP[bx]
|
|||
|
|
|
|||
|
|
assembles as
|
|||
|
|
|
|||
|
|
mov ax,es:[bx]
|
|||
|
|
|
|||
|
|
in compact, large, and huge memory models, but as
|
|||
|
|
|
|||
|
|
mov ax,[bx]
|
|||
|
|
|
|||
|
|
in small and medium models.
|
|||
|
|
|
|||
|
|
pLes register,address
|
|||
|
|
pLds register,address
|
|||
|
|
|
|||
|
|
Loads a pointer from the specified address to the specified
|
|||
|
|
register. If the memory model uses far data, the segment
|
|||
|
|
portion of the address will be moved into ES or DS, depending
|
|||
|
|
on the macro used. For example,
|
|||
|
|
|
|||
|
|
pLes bx,arg1
|
|||
|
|
|
|||
|
|
is assembled as
|
|||
|
|
|
|||
|
|
les bx,arg1
|
|||
|
|
|
|||
|
|
in compact, large, and huge memory models, but as
|
|||
|
|
|
|||
|
|
mov bx,arg1
|
|||
|
|
|
|||
|
|
in small and medium models.
|
|||
|
|
|
|||
|
|
Notes
|
|||
|
|
|
|||
|
|
The macros in MIXED.INC have several limitations:
|
|||
|
|
|
|||
|
|
1. The memory model must be set at the start of the source
|
|||
|
|
file before any mixed-language macros are used. The model
|
|||
|
|
can be set with the .MODEL directive or with the "setModel"
|
|||
|
|
macro. For example, start with
|
|||
|
|
|
|||
|
|
INCLUDE mix.inc
|
|||
|
|
.MODEL small
|
|||
|
|
|
|||
|
|
or with
|
|||
|
|
|
|||
|
|
model EQU <small> ; Or pass small from command line
|
|||
|
|
INCLUDE mix.inc
|
|||
|
|
setModel
|
|||
|
|
|
|||
|
|
The mixed-language macros only work with simplified segment
|
|||
|
|
directives. You cannot use them with full segment definitions.
|
|||
|
|
|
|||
|
|
2. If the C calling convention is used, the symbol "cLang"
|
|||
|
|
must be defined before the start of a procedure. For
|
|||
|
|
example, define the symbol in the source file with the line
|
|||
|
|
|
|||
|
|
cLang = 1
|
|||
|
|
|
|||
|
|
or from the command line with the option
|
|||
|
|
|
|||
|
|
/DcLang
|
|||
|
|
|
|||
|
|
3. The macros do not automatically handle 80386 features such
|
|||
|
|
as 32-bit pointers.
|
|||
|
|
|
|||
|
|
4. All limitations and techniques described the Mixed-Language
|
|||
|
|
Programming Guide apply. For instance, you must save and
|
|||
|
|
restore the DS, SS, DI, and SI registers if your module
|
|||
|
|
modifies them. Return values should be passed back by
|
|||
|
|
placing them in AL, AX, or DX:AX before returning.
|
|||
|
|
|
|||
|
|
5. FORTRAN and Pascal require that the address for certain
|
|||
|
|
return values (such as real numbers or arrays) be passed as
|
|||
|
|
the last argument. The macros do not handle this situation,
|
|||
|
|
so the programmer must handle it specifically. An example
|
|||
|
|
is shown below:
|
|||
|
|
|
|||
|
|
hProc FuncFORTRAN,Arg1,Arg2,RetPoint
|
|||
|
|
.
|
|||
|
|
.
|
|||
|
|
.
|
|||
|
|
mov RetPoint,bx ; Assume BX contains a pointer
|
|||
|
|
; to return value
|
|||
|
|
Return
|
|||
|
|
|
|||
|
|
6. The convenience of using the macros in MIXED.INC has a cost
|
|||
|
|
in slower assembly time.
|
|||
|
|
|
|||
|
|
Examples
|
|||
|
|
|
|||
|
|
The file POWER2.ASM contains a sample assembly module that is
|
|||
|
|
equivalent to the sample modules in BA.ASM, CA.ASM, FA.ASM, and
|
|||
|
|
PA.ASM. POWER2.ASM uses the macros in MIXED.INC and can be
|
|||
|
|
assembled from the command-line for any language or memory
|
|||
|
|
model. The module can be linked with the high-level-language
|
|||
|
|
modules created from BAMAIN.BAS, CAMAIN.C, FAMAIN.FOR, or
|
|||
|
|
PAMAIN.PAS. The command lines for default memory models are
|
|||
|
|
shown below for each language:
|
|||
|
|
|
|||
|
|
BASIC - CodeView symbolic data and medium model
|
|||
|
|
|
|||
|
|
MASM /ZI /Dmodel=medium power2;
|
|||
|
|
|
|||
|
|
C - Case sensitive, CodeView symbolic data, small model, and "cLang" defined
|
|||
|
|
|
|||
|
|
MASM /Mx /Zi /Dmodel=small /DcLang power2;
|
|||
|
|
|
|||
|
|
FORTRAN - CodeView symbolic data and large model
|
|||
|
|
|
|||
|
|
MASM /ZI /Dmodel=large power2;
|
|||
|
|
|
|||
|
|
Pascal - CodeView symbolic data and large model
|
|||
|
|
|
|||
|
|
MASM /ZI /Dmodel=large power2;
|
|||
|
|
|