Intel i960 - Page 96

i960 Processor Compiler User's Guide
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3
Default
By default, the compiler uses the i960 KB architecture. The I960ARCH
environment variable can override the default architecture.
Discussion
Use the A (Architecture) option to specify the target instruction set. This
option overrides the environment variable
I960ARCH. See also the
-Gcore0, -Gcore1, -Gcore2, and -Gcore3 options that let you generate
code that is compatible with multiple i960 processor types.
NOTES. Also, with release 5.1 using the -ARP option generates code
that is compatible with current and proposed future variations on the i960
RP architecture.
You can use predefined macros in your source text to conditionally
compile code for the selected architecture. The compiler defines a
preprocessor macro indicating the selected architecture. The preprocessor
macro takes the form:
__i960 xx
xx
is CA, CF, KA, KB, RP, SA, SB, HA, HD, HT, JA, JD,
or
JF. The compiler selects the value of xx
according to the architecture you specify.
In addition to
__i960 xx , the __i960 macro is defined for all architecture
selections. Use
__i960 to identify parts of your program specific to the
i960 architecture but not necessarily specific to a particular processor.
In addition, for compatibility with earlier releases, macros of the forms:
i960, _ _i960_ _, _ _i960 xx_ _ and _ _i960_ xx_ _ are defined.
If you link object modules compiled with incompatible architectures, the
linker displays the following warning message: