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Linux Assembler: which registers to preserve?

When calling an assembler routine from within a Win32
context, it is clear that the values of EAX, ECX, and EDX
don't have to be preserved (while e.g. EBX, EBP, and ...
have to be preserved).

Can anyone enlighten me, which registers have to be preserved
when calling an assembler routine from within a Linux context?

(context = c or c++ program)

trigger-happy

It depends on the calling convention that use since both platforms adhere to it:
http://www.programmersheaven.com/2/Calling-conventions

--trigger-happy

norsethomas

ASKER

trigger-happy,

thanks for the link, but it doesn't answer my question.

Thomas

trigger-happy

oh sorry >.<

I must admit now that i'm not a complete expert in assembly so forgive me if i can't seem to answer your question, although one thing bothers me, is this homework? Because its in EE policies that we don't give answers to homework but instead guide you in finding the answer.

http://www.digitalmars.com/ctg/ctgInlineAsm.html (check the part about using asm registers)

--trigger-happy

norsethomas

ASKER

No, this is a real world problem, since I have to know
if I have to recode my assembler routines when
porting to Linux (i.e. saving more registers).

Your second link just gives an answer for Win32,
which I already know ;-)

Thomas

SOLUTION

trigger-happy

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ASKER CERTIFIED SOLUTION

dimitry

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