2. The DML compiler

A DML source file can be compiled into a runnable device model using the DML compiler, dmlc. The main output of the compiler is a C file, that can be compiled into a Simics module.

The DML compiler and its libraries are available as part of the Simics Base package.

Building dmlc

The dmlc compiler can be build locally. This requires an installation of the Simics 6 base package.

In order to build the compiler, you can copy source directory dmlc into the modules subdirectory of your Simics project. The compiler can be built using the make dmlc command. The build result ends up in host/bin/dml (where host is linux64 or win64), and consists of three parts:

• host/bin/dml/python contains the Python module that implements the compiler

• host/bin/dml/1.4 contains the standard libraries required to compile a device

• host/bin/dml/api contains .dml files that expose the Simics API

In order to use a locally built version of dmlc to compile your devices, you can add the following line to your config-user.mk file:

DMLC_DIR = $(SIMICS_PROJECT)/$(HOST_TYPE)/bin

Running dmlc

The syntax for running dmlc from the command line is:

dmlc [options] input [output-base]

where input should be the name of a DML source file. If output-base is provided, it will be used to name the created files. The name of a DML source file should normally have the suffix ".dml". The input file must contain a device declaration.

The main output of dmlc is a C file named <output-base>.c, which that can be compiled and linked into a Simics module using the gcc compiler. The compiler also produces some other helper files with .h and .c suffix, which the main output file includes.

Command Line Options

The following are the available command line options to dmlc:

-h, --help

Print usage help.

-I path

Add path to the search path for imported modules.

-D name=definition

Define a compile-time parameter. The definition must be a literal expression, and can be a quoted string, a boolean, an integer, or a floating point constant. The parameter will appear in the top-level scope.

--dep

Output makefile rules describing dependencies.

-T

Show tags on warning messages. The tags can be used with the --nowarn and --warn options.

-g

Generate code suitable for source-level debugging. This will generate C code that follows the DML code more closely.

--warn=tag

Enable selected warnings. The tags can be found using the -T option.

--nowarn=tag

Suppress selected warnings. The tags can be found using the -T option.

--werror

Turn all warnings into errors.

--strict

Report errors for some constructs that will be forbidden in future versions of the DML language

--noline

Suppress line directives for the C preprocessor so that the C code can be debugged.

--info

Enable the output of an XML file describing register layout.

--version

Print version information.

--simics-api=version

Use Simics API version version.

--max-errors=N

Limit the number of error messages to N.