Texas Instruments TMS320C54x, Руководство пользователя

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Define Macro Library
.mlib
4-67 Assembler Directives
Syntax
.mlib [”] filename[”]
Description The .mlib directive provides the assembler with the name of a macro library.
A macro library is a collection of files that contain macro definitions. These files
are bound into a single file (called a library or archive) by the archiver. Each
member of a macro library may contain one macro definition that corresponds
to the name of the file. Macro library members must be
source files (not object
files).
The filename of a macro library member must be the same as the macro name,
and its extension must be .asm. The
filename must follow host operating sys-
tem conventions; it may be enclosed in double quotes. You can specify a full
pathname (for example, c:\dsp\macs.lib). If you do not specify a full pathname,
the assembler searches for the file in:
1) The directory that contains the current source file
2) Any directories named with the –i assembler option
3) Any directories specified by the environment variable A_DIR
For more information about the –i option and the environment variable, see
Section 3.4,
Naming Alternate Directories for Assembler Input, on page 3-7.
When the assembler encounters a .mlib directive, it opens the library and
creates a table of the library’s contents. The assembler enters the names of
the individual library members into the opcode table as library entries. This re-
defines any existing opcodes or macros that have the same name. If one of
these macros is called, the assembler extracts the entry from the library and
loads it into the macro table. The assembler expands the library entry in the
same way it expands other macros, but it does not place the source code into
the listing. Only macros that are actually called from the library are extracted,
and they are extracted only once.