[llvm-commits] [llvm] r84134 - in /llvm/trunk/lib/CodeGen/AsmPrinter: DwarfDebug.cpp DwarfDebug.h

[Devang Patel]

done. There are other instances where we use WeakVH and ValueMap in DwarfDebug. I'll clean them up in a separate patch.
-
Devang
On Jan 15, 2010, at 2:30 PM, Chris Lattner wrote:

> 
> On Jan 15, 2010, at 2:06 PM, Devang Patel wrote:
> 
>> 
>> On Jan 15, 2010, at 1:52 PM, Chris Lattner wrote:
>> 
>>> ping?
>> 
>> Right now, FE relies on MDNode::replaceAllUsesWith. We need to come up of another way to handle recursive constructs in FE.
> 
> This code is in the code generator's asmwriter, not in the frontend.  The frontend should be done by the time these are created.
> 
>> Plus,
>> MDNode's replaceOperand may also trigger MDNode::replaceAllUsesWith. So, Between beginFunction() and endFunction(), if metadata changes (Dale is introducing new machine instruction with a metadata operand, which may change during codegen pipeline) then we need WeakVH to track MDNode.
>> 
>> I have not had a chance to measure DbgScope's impact on performance. I'll do the measurement then update it, if required, appropriately. Meanwhile, I am adding FIXME now.
> 
> The code generator should only be run when the metadata is all done, I don't see how it can change here.
> 
> -Chris