[llvm-commits] [llvm] r133286 - in /llvm/trunk: include/llvm/MC/MCStreamer.h include/llvm/Target/TargetRegistry.h lib/CodeGen/LLVMTargetMachine.cpp lib/MC/MCAsmStreamer.cpp lib/Target/PTX/PTXMCAsmStreamer.cpp lib/Target/PTX/PTXTargetMachine.cpp tools/llvm-mc/llvm-mc.cpp

[Bill Wendling]

On Jun 17, 2011, at 9:48 PM, Chris Lattner wrote:
> On Jun 17, 2011, at 1:55 PM, Bill Wendling wrote:
>> I can do that. I did it this way to give people the option of not having it emitted when they don't want it. But having it default to "on" for -asm-verbose works for me too.
> 
> Please do, and remove the extra bools and flags.  People either want verbose asm or not, we don't want lots of flags and options.
> 
Done.

>>> Also, why is this implemented by subclassing MCAsmStreamer?  Can't the code generator just emit this as verbose asm comments instead of reconstructing it?
>> 
>> I actually do some of that now (see below). It's not the most readable thing in the world, but could be made a bit better. One major benefit of making it a subclass of MCAsmStreamer, however, is that you can run it on a .s file which doesn't have verbose comments in them. I would really like to maintain that ability.
> 
> Why is this important?  Who is it important for?
> 
The motivation for this was for the person who gets a random .s file, or even one that they've built themselves, and needs to understand what the EH table means -- people who get an EH bug report and/or those just starting out looking at exception handling but who haven't deciphered the Eh table documentation yet. More the former group than the latter, but the latter can use it as an instructional aide.

This becomes even more important for SjLj EH, since the EH table isn't documented in the same way the DWARF EH table is.

-bw