Hi,
> : la a0, dec_signon
> :
> : "la" is not an op code that shows up in either Mips Risc Architecture
> : or the MIPs IV instruction set manual
>
> LA == Load Address. It is a pseudo-op in gas. It literally
> translates to:
>
> lui a0, %hi(dec_signon)
> addiu a0, a0, %lo(dec_signon)
>
> Which is effectively loading the address into a0.
>
> I just discovered this because I was looking at a disassembled version
> of rpc44.o to make sure that it mached rpc44.S (which it did, except
> for things like this). And now that I recall, I think there was email
> about milo's disassembler that stated that it had been modified to
> merge these two instructions into one.
This is not the only macro instruction in MIPS assembler; in fact most of
the instructions are macro instructions that expand sometimes into five
instructions or more. Many of them are described in the appendix of
the Kane.
Ralf
Name : MIPS RISC Architecture
Author : Gerry Kane
Publisher: Prentice Hall, Englewood Cliffs, N.J. 07632
ISBN : 0-12-58479-4
The book contains another ISBN: 0-13-584293-X, so
be carefull.
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