Re: patch for 930513-1 on Darwin

[Dale Johannesen <dalej at apple dot com>]

On Thursday, May 31, 2001, at 05:03  PM, Geoff Keating wrote:

> dalej@apple.com writes:
>
>> Background:
>> We have a longstanding failure on test execute/930513-1.c with -O3 for
>> Darwin.  What happens is that a function name is passed to a callee,
>> which expects a pointer-to-function, which is dereferenced and called.
>> When the callee is expanded inline, the nested call becomes a direct
>> call to the function name.  On Darwin, the required syntax for a
>> function name is different when you call it and when you pass its
>> address, so the inliner needs to change things to compensate.  I don't
>> see any hooks for this in integrate.c (perhaps by coincidence, no other
>> machine I know of has such a requirement) so I added a macro.  There
>> will be no functional change on any other target.
>>
>> 2001-05-31  Dale Johannesen  <dalej@apple.com>
>>
>>          * integrate.c, config/rs6000/darwin.h:  for Darwin, change
>> function name
>>             syntax when function passed as parameter is called, due to
>> inlining.  Macro
>>            ADJUST_CALLEE_SYM_NAME added.  Functional change on Darwin
>> only.
>
> Why can't this transformation be done in the call patterns of the MD 
> file?
> I think that's how it's done for AIX.

Maybe.  Could you be more specific?  I looked at the AIX code, but it 
looked like the problem didn't occur there.  Presumably you would 
generate a call_indirect_aix32 (or variant) originally, which matches 
*call_indirect_nonlocal_aix32 later, but that only accepts a register as 
op0.  In the problem case this inliner has changed this to a symbol_ref, 
and I don't see anything that matches that.  Which led me to believe 
that the inliner doesn't do this substitution in the AIX case, which is 
plausible as the call_indirect_aix32 code is more complex.  Of course 
I'd like to look at what actually happens on AIX, but I don't have one.