[fpc-devel] Stackframes

[Florian Klämpfl]

Am 27.08.2011 12:50, schrieb Michael Van Canneyt:
> 
> 
> On Sat, 27 Aug 2011, Ludo Brands wrote:
> 
>> In
>> http://www.freepascal.org/docs-html/prog/progsu72.html#x78-770001.1.72 is
>> written:
>>
>> ...
>> the compiler will omit the generation of a stackframe if the following
>> conditions are satisfied:
>>
>>    The procedure has no parameters.
>> ...
>>
>> This condition should read: The procedure has no parameters on the stack.
>> Parameters passed in registers do not trigger stackframe generation.
>>
>> There are a lot of wrapper functions, with register only parameters,
>> in the
>> rtl and elsewhere that don't generate stack frames.
> 
> If the compiler developers can confirm this, then I'll adapt the
> documentation.

Find some generic text aiming on complexity or whatever :) The rules
when it happens or not are pretty complex, they also depend on the
target architecture. See e.g. psub.pas:953+ and all occurences of
pi_needs_stackframe in the compiler