Where can i find asm operand constraints?

[Russ.Shaw]

Hi all,

I'm using gcc as a cross compiler for the hitachi h8/300h
micro-controller core.

When doing asm statements in C, operand constraints are
needed. I can't find a list of the valid constraints.
Does anyone know what source file they'd be listed in?
TIA

-- 
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*   Russell Shaw, B.Eng, M.Eng(Research)  *
*      email: russell@webaxs.net          *
*      Australia                          *
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