llvm dev - Oct 2010 - [LLVMdev] Splitting a basic block creates an instruction without debug metadata

Hi,

I'm not sure if this is really a problem or not, but I noticed that if  
you're working with bitcode that has debug metadata, and you split a  
BasicBlock using llvm::SplitBlock or BasicBlock::splitBasicBlock, the  
unconditional branch added to the new block will lack debug metadata.  
This turned out not to be a problem for me, since my analysis pass  
needs only one instruction in the block to have metadata, but perhaps  
it will be a problem for others. Ignoring for now the issue of just  
how to manufacture the metadata for the new instruction, is this a bug?

Trevor

On Oct 27, 2010, at 5:53 PM, Trevor Harmon wrote:
> Hi,
> 
> I'm not sure if this is really a problem or not, but I noticed that if
> you're working with bitcode that has debug metadata, and you split a  
> BasicBlock using llvm::SplitBlock or BasicBlock::splitBasicBlock, the  
> unconditional branch added to the new block will lack debug metadata.  
> This turned out not to be a problem for me, since my analysis pass  
> needs only one instruction in the block to have metadata, but perhaps  
> it will be a problem for others. Ignoring for now the issue of just  
> how to manufacture the metadata for the new instruction, is this a bug?
> 
It'd be good to have location info attached with newly created unconditional
branch.
-
Devang

On Oct 28, 2010, at 9:46 AM, Devang Patel wrote:
> It'd be good to have location info attached with newly created  
> unconditional branch.
Okay, filed as bug #8510.

http://llvm.org/bugs/show_bug.cgi?id=8510

Trevor