i have a question about putting things on the stack for x86 arch under plan 9...<div><br></div><div>under unix/linux, when defining a function, i would:</div><div>(1). push the address the base pointer is pointing to prior to this function being called, onto the stack; e.g. pushl %ebp</div>
<div>(2). then i would have the base pointer point to the current stack pointer; e.g. movl %esp, %ebp</div><div>(3). then i would allocate space on the stack for local variables, if any; e.g. subl $n, %esp;</div><div>(4). then follows the function body;</div>
<div>to return from the function i would:</div><div>(1). restore the stack pointer; e.g. movl %ebp, %esp;</div><div>(2). restore the base pointer, e.g. popl %ebp;</div><div>(3). then return to the calling function;</div><div>
<br></div><div>i searched the 9fans archives for posts on assembly programming under plan 9; found some bits and pieces; e.g. in one of the posts it was mentioned that BP is a general purpose register, not the base pointer; and that FP is what ebp is under unix/linux;</div>
<div><br></div><div>in the paper for the plan 9 assembler, it says that there are three registers available to manipulate the stack, FP, SP, and TOS; would the following comparison stand true then?</div><div>plan9    unix/linux</div>
<div>-------     -------------</div><div>FP        EBP</div><div>SP        -4(%EBP)...-n(%EBP) /* local variables */</div><div>TOS     ESP</div><div><br></div><div>thanks;</div><div><br></div><div>sasha kapshuk</div><div>
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