12 Nov
2010
12 Nov
'10
10:56 a.m.
Dear Graeme Russ,
In message 4CDD0D1F.7010805@gmail.com you wrote:
Passing gd as parameter makes no sense, thoug, as it's global data and we reserve a register to store it's address, so it can always be used with minimal overhead.
Which is a really nice idea if you have a register to spare. Unfortunately, x86 does not have this luxury, and the only way I can get gd (and as a consequence upper memory bound for relocation) is to allocate it in assembler and pass to C as a function argument
Agreed - x86 has always it's own set of limitations.
Best regards,
Wolfgang Denk
--
DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel
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In the pitiful, multipage, connection-boxed form to which the flow-
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design tool -- programmers draw flowcharts after, not before, writing
the programs they describe. - Fred Brooks, Jr.