[LLVMdev] [lld] -emit-yaml doesnot contain linker added symbols specified with command line options

[Nick Kledzik]

On Aug 28, 2013, at 3:14 PM, Shankar Easwaran <shankare at codeaurora.org> wrote:
> Hi Nick,
> 
> The problem is when the -emit-yaml option is used, the writer is set to the YAML writer.
Ah!

> 
> The YAML writer does not have anything to add here.
> 
> The problem can be solved by having the YAML writer append a list of undefined atoms specified by the -u option, but the problem I have is each flavor has extra command line options
> for which it wants to create a DefinedAtom/UndefinedAtom. The flavor also may want to add extra linker internal files in the future.
> 
> I prefer addImplicitFiles calling the reader to add more files, which means addFiles API moves to the reader.
But won’t that fail too if you were using a YAML Reader and ELF Writer?  

Since we are talking about files/atoms that are created because of command line options, perhaps the Driver should be creating the files/atoms.  In the case of -u, it would be nice to group them all in one file named “command line option -u” so that any error messages about undefined symbols says the references was from “command line option -u”  (as opposed to the -u UndefinedAtoms come from a generic internal file).  Also for the case of -u, the Driver can make generic UndefinedAtoms.  Other options may need platform specific atoms which may be created with the help of static Writer methods.

-Nick


> On 8/28/2013 4:57 PM, Nick Kledzik wrote:
>> Shankar,
>> 
>> The LinkingContext has a addImplictFiles() method that is supposed to call the Writer and give it a chance to add any implicit files.  Is the problem that the -u atoms are not attached to that implicit file?  Or that the implicit file is not getting added?  Or that this got lost in the transition from InputFiles to InputGraph?
>> 
>> -Nick
>> 
>> On Aug 28, 2013, at 2:44 PM, Shankar Easwaran <shankare at codeaurora.org> wrote:
>>> Right now, linker added symbols specified by the -u option do not endup in the output YAML file.
>>> 
>>> This is because the target specific Writers dont get called, which creates the undefined atoms.
>>> 
>>> I am in the process of adding more options and I would like the atoms created internally by the options available in the output YAML file.
>>> 
>>> The options that I am trying to consider for the linker internal atoms to appear in the output YAML file are :-
>>> 
>>> a) Replace Writer::addFiles to Reader::addFiles
>>> 
>>> This would achieve any file to be added to the list of input files that is processed.
>>> 
>>>                              (or)
>>> b) Create a seperate API in the inputGraph for the driver to add lld::Files, that are consumed by the Universal driver and that gets
>>> added to the list of File objects that is being considered
>>> 
>>>                              (or)
>>> 
>>> c) Handle all the command line switches of -u or any atoms that we want to see them appear in the YAML file as a seperate pass.
>>> 
>>> I dont like the option (c), because we are using a hammer to kill this problem.
>>> 
>>> Thanks
>>> 
>>> Shankar Easwaran
>>> -- 
>>> 
>>> Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by the Linux Foundation
>> 
>> 
> 
> 
> -- 
> Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by the Linux Foundation