llvm dev - Mar 2005 - [LLVMdev] Recursive Types using the llvm support library

----- Original Message ----- 
From: "Chris Lattner" <sabre at nondot.org>
To: "LLVM Developers Mailing List" <llvmdev at cs.uiuc.edu>
Sent: Tuesday, March 08, 2005 6:31 PM
Subject: Re: [LLVMdev] Recursive Types using the llvm support library

> On Tue, 8 Mar 2005, Vladimir Merzliakov wrote:
>
>>>> An example where something really simple like the line below
was output
>>>> would be perfect.
>>>>
>>>> %struct.linked_list = type { %struct.linked_list*, %sbyte* }
>>>
>>> Use something like this:
>>>
>>>   PATypeHolder StructTy = OpaqueType::get();
>>>   std::vector<const Type*> Elts;
>>>   Elts.push_back(PointerType::get(StructTy));
>>>   Elts.push_back(PointerType::get(Type::SByteTy));
>>>   StructType *NewSTy = StructType::get(Elts);
>>>
>>>   // At this point, NewSTy = "{ opaque*, sbyte* }", tell
VMCore that
>>>   // the struct and the opaque type are actually the same.
>>>  
cast<OpaqueType>(StructTy.get())->refineAbstractTypeTo(NewSTy);
>>>
>>>   // NewSTy is potentially invalidated, but StructTy (a
PATypeHolder) is
>>>   // kept up-to-date.
>>>   NewSTy = StructTy.get();
>>>
>> Is assert(!NewSTy->isAbstract()) must pass  after this line?
>
> In this case, yup.
>
I create test program and assert failed in it:

{ \2 *, sbyte * }
Assertion failed: (!NewSTy->isAbstract()), function main, file 
/usr/home/wanderer/work/LLVMTest/obj/../src/tools/tool/Test.cc, line 28.

Testcase source attached.

Vladimir
-------------- next part --------------
A non-text attachment was scrubbed...
Name: Test.cc
Type: application/octet-stream
Size: 796 bytes
Desc: not available
URL:
<http://lists.llvm.org/pipermail/llvm-dev/attachments/20050309/f9463a01/attachment.obj>

On Wed, 9 Mar 2005, Vladimir Merzliakov wrote:
> I create test program and assert failed in it:
>
> { \2 *, sbyte * }
> Assertion failed: (!NewSTy->isAbstract()), function main, file 
> /usr/home/wanderer/work/LLVMTest/obj/../src/tools/tool/Test.cc, line 28.
>
> Testcase source attached.
Thanks, that definitely is a bug.  Patch here:
http://mail.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20050307/024522.html

BTW, what are you using the isAbstract bit for?

-Chris

-- 
http://nondot.org/sabre/
http://llvm.cs.uiuc.edu/

> On Wed, 9 Mar 2005, Vladimir Merzliakov wrote:
>> I create test program and assert failed in it:
>>
>> { \2 *, sbyte * }
>> Assertion failed: (!NewSTy->isAbstract()), function main, file 
>> /usr/home/wanderer/work/LLVMTest/obj/../src/tools/tool/Test.cc, line
28.
>>
>> Testcase source attached.
>
> Thanks, that definitely is a bug.  Patch here:
>
http://mail.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20050307/024522.html
>
> BTW, what are you using the isAbstract bit for?
In some asserts in my YAFL frontend (may be i will have free time to finish 
it).

Vladimir

On Wed, Mar 09, 2005 at 04:05:32PM +0300, Vladimir Merzliakov
wrote:
> >>Is assert(!NewSTy->isAbstract()) must pass  after this line?
> >
> >In this case, yup.
> >
> I create test program and assert failed in it:
> 
> { \2 *, sbyte * }
How do I decode the \2 in this?  I am creating types through this
interface and I get quite a mess seen below.  And this is relatively
simple.  Any ideas?

-John


	alloca { { int, uint, sbyte*, \4* (), \4* (\4*), { { int, uint, sbyte*, \4* (),
{ { int, uint, sbyte*, \4 (), \4 (\4), \8* (\4), \4 (\4) } }* (\4*), \4* (\4*),
\4* (\4*), { { int, uint, sbyte*, \4 (), \4 (\4), \8* (\4), \4 (\4) } }* (\4*),
\4* (\4*, \4*), \4* (\4*, { { int, uint, sbyte*, \4 (), \4 (\4), \8* (\4), \4
(\4) } }*, { { int, uint, sbyte*, \4 (), \4 (\4), \8* (\4), \4 (\4) } }*) } }*
(\4*), \4* (\4*) } }		; <{ { int, uint, sbyte*, \4* (), \4* (\4*), { { int,
uint, sbyte*, \4* (), { { int, uint, sbyte*, \4 (), \4 (\4), \8* (\4), \4 (\4) }
}* (\4*), \4* (\4*), \4* (\4*), { { int, uint, sbyte*, \4 (), \4 (\4), \8* (\4),
\4 (\4) } }* (\4*), \4* (\4*, \4*), \4* (\4*, { { int, uint, sbyte*, \4 (), \4
(\4), \8* (\4), \4 (\4) } }*, { { int, uint, sbyte*, \4 (), \4 (\4), \8* (\4),
\4 (\4) } }*) } }* (\4*), \4* (\4*) } }*>:2 [#uses=0]

On Sun, 20 Mar 2005, John Carrino wrote:
> On Wed, Mar 09, 2005 at 04:05:32PM +0300, Vladimir Merzliakov wrote:
>>>> Is assert(!NewSTy->isAbstract()) must pass  after this line?
>>>
>>> In this case, yup.
>>>
>> I create test program and assert failed in it:
>>
>> { \2 *, sbyte * }
>
> How do I decode the \2 in this?  I am creating types through this
> interface and I get quite a mess seen below.  And this is relatively
> simple.  Any ideas?
"\2" is an upreference, which refers to a containing type.  For
example,
this type:

  \1*

Is a pointer to pointer to pointer to pointer....  In "{\2*}", the 
upreference refers to the structure type, not the pointer, with \4, it 
means go 4 types up etc.

In practice, this is leads to a horrible mess, as you've noticed.  As 
such, I'd suggest using Module::addTypeName to give these things names so 
that you have a hope to understand them and so they are more compact :)

-Chris

> 	alloca { { int, uint, sbyte*, \4* (), \4* (\4*), { { int, uint, sbyte*,
\4* (), { { int, uint, sbyte*, \4 (), \4 (\4), \8* (\4), \4 (\4) } }* (\4*), \4*
(\4*), \4* (\4*), { { int, uint, sbyte*, \4 (), \4 (\4), \8* (\4), \4 (\4) } }*
(\4*), \4* (\4*, \4*), \4* (\4*, { { int, uint, sbyte*, \4 (), \4 (\4), \8*
(\4), \4 (\4) } }*, { { int, uint, sbyte*, \4 (), \4 (\4), \8* (\4), \4 (\4) }
}*) } }* (\4*), \4* (\4*) } }		; <{ { int, uint, sbyte*, \4* (), \4* (\4*), {
{ int, uint, sbyte*, \4* (), { { int, uint, sbyte*, \4 (), \4 (\4), \8* (\4), \4
(\4) } }* (\4*), \4* (\4*), \4* (\4*), { { int, uint, sbyte*, \4 (), \4 (\4),
\8* (\4), \4 (\4) } }* (\4*), \4* (\4*, \4*), \4* (\4*, { { int, uint, sbyte*,
\4 (), \4 (\4), \8* (\4), \4 (\4) } }*, { { int, uint, sbyte*, \4 (), \4 (\4),
\8* (\4), \4 (\4) } }*) } }* (\4*), \4* (\4*) } }*>:2 [#uses=0]
>
> _______________________________________________
> LLVM Developers mailing list
> LLVMdev at cs.uiuc.edu         http://llvm.cs.uiuc.edu
> http://mail.cs.uiuc.edu/mailman/listinfo/llvmdev
>
-Chris

-- 
http://nondot.org/sabre/
http://llvm.cs.uiuc.edu/