Renamed variables to be more reflective of whether they are
an instance of Linker, IRLinker or ModuleLinker. Also fix a stale
comment.
llvm-svn: 256011
Summary:
Second patch split out from http://reviews.llvm.org/D14752.
Maps metadata as a post-pass from each module when importing complete,
suturing up final metadata to the temporary metadata left on the
imported instructions.
This entails saving the mapping from bitcode value id to temporary
metadata in the importing pass, and from bitcode value id to final
metadata during the metadata linking postpass.
Depends on D14825.
Reviewers: dexonsmith, joker.eph
Subscribers: davidxl, llvm-commits, joker.eph
Differential Revision: http://reviews.llvm.org/D14838
llvm-svn: 255909
This patch converts code that has access to a LLVMContext to not take a
diagnostic handler.
This has a few advantages
* It is easier to use a consistent diagnostic handler in a single program.
* Less clutter since we are not passing a handler around.
It does make it a bit awkward to implement some C APIs that return a
diagnostic string. I will propose new versions of these APIs and
deprecate the current ones.
llvm-svn: 255571
A linker normally has two stages: symbol resolution and "moving stuff".
In lib/Linker there is the complication of lazy linking some globals,
but it was still far more mixed than it needed to.
This splits the linker into a lower level IRMover and the linker proper.
The IRMover just takes a list of globals to move and a callback that
lets the user control what is lazy linked.
The main motivation is that now tools/gold (and soon lld) can use their
own symbol resolution to instruct IRMover what to do.
llvm-svn: 255254
Now instead of changing it to the new format and then linking, it just
handles the old format while copying it over.
The main differences are:
* There is no rauw in the source module.
* An old format input is always upgraded.
The first item helps with having a sane API that passes in a GV list to
the linker.
The second one is a small step in deprecating the old format.
llvm-svn: 254907
Before this patch the diagnostic handler was optional. If it was not
passed, the one in the LLVMContext was used.
That is probably not a pattern we want to follow. If each area has an
optional callback, there is a sea of callbacks and it is hard to follow
which one is called.
Doing this also found cases where the callback is a nice addition, like
testing that no errors or warnings are reported.
The other option is to always use the diagnostic handler in the
LLVMContext. That has a few problems
* To implement the C API we would have to set the diag handler and then
set it back to the original value.
* Code that creates the context might be far away from code that wants
the diagnostics.
I do have a patch that implements the second option and will send that as
an RFC.
llvm-svn: 254777
Summary:
Fix import from module with appending var, which cannot be imported. The
first fix is to remove an overly-aggressive error check.
The second fix is to deal with restructuring introduced to the module
linker yesterday in r254418 (actually, this fix was included already
in r254559, just added some additional cleanup).
Test by Mehdi Amini.
Reviewers: joker.eph, rafael
Subscribers: joker.eph, llvm-commits
Differential Revision: http://reviews.llvm.org/D15156
llvm-svn: 254624
There is no real reason the index has to have the concept of an
exporting Module. We should be able to have one single unique
instance of the Index, and it should be read-only after creation
for the whole ThinLTO processing.
The linker plugin should be able to process multiple modules (in
parallel or in sequence) with the same index.
The only reason the ExportingModule was present seems to be to
implement hasExportedFunctions() that is used by the Module linker
to decide what to do with the current Module.
For now I replaced it with a query to the map of Modules path to
see if this module was declared in the Index and consider that if
it is the case then it is probably exporting function.
On the long term the Linker interface needs to evolve and this
call should not be needed anymore.
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 254581
This replaces DoNotLinkFromSource with ValuesToLink. It also moves the
computation of ValuesToLink earlier.
It is a bit simpler and an important step in slitting the linker into an
ir mover and a linker proper.
The test change is because we now avoid creating dead declarations.
llvm-svn: 254559
Having to import an alias as declaration is not thinlto specific.
The test difference are because when we already have a decl and we are
not importing it, we just leave the decl alone.
llvm-svn: 254556
For efficiency reason, when importing multiple functions for the same Module,
we can avoid reparsing it every time.
Differential Revision: http://reviews.llvm.org/D15102
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 254486
It was only used from LTO for a debug feature, and LTO can just create
another linker.
It is pretty odd to have a method to reset the module in the middle of a
link. It would make IdentifiedStructTypes inconsistent with the Module
for example.
llvm-svn: 254434
It has to be a bit special because:
* materializeInitFor is not really supposed to call replaceAllUsesWith.
The caller has a plain variable with Dst and expects just the
initializer to be set, not for it to be removed.
* Calling mutateType as we used to do before gets some type
inconsistency which breaks the bitcode writer.
* If linkAppendingVarProto create a dest decl with the correct type to
avoid the above problems, it needs to put the original dst init in
some side table for materializeInitFor to use.
In the end the simplest solution seems to be to just have
linkAppendingVarProto do all the work and set ValueMap[SrcGV to avoid
recursion.
llvm-svn: 254424
The difference is that now we don't error on out-of-comdat access to
internal global values. We copy them instead. This seems to match the
expectation of COFF linkers (see pr25686).
Original message:
Start deciding earlier what to link.
A traditional linker is roughly split in symbol resolution and
"copying
stuff".
The two tasks are badly mixed in lib/Linker.
This starts splitting them apart.
With this patch there are no direct call to linkGlobalValueBody or
linkGlobalValueProto. Everything is linked via WapValue.
This also includes a few fixes:
* A GV goes undefined if the comdat is dropped (comdat11.ll).
* We error if an internal GV goes undefined (comdat13.ll).
* We don't link an unused comdat.
The first two match the behavior of an ELF linker. The second one is
equivalent to running globaldce on the input.
llvm-svn: 254418
A traditional linker is roughly split in symbol resolution and "copying
stuff".
The two tasks are badly mixed in lib/Linker.
This starts splitting them apart.
With this patch there are no direct call to linkGlobalValueBody or
linkGlobalValueProto. Everything is linked via WapValue.
This also includes a few fixes:
* A GV goes undefined if the comdat is dropped (comdat11.ll).
* We error if an internal GV goes undefined (comdat13.ll).
* We don't link an unused comdat.
The first two match the behavior of an ELF linker. The second one is
equivalent to running globaldce on the input.
llvm-svn: 254336
Now the ValueMapper has two callbacks. The first one maps the
declaration. The ValueMapper records the mapping and then materializes
the body/initializer.
llvm-svn: 254209
They are as much trouble as aliases to declarations. They are requiring
the code generator to define a symbol with the same value as another
symbol, but the second symbol is undefined.
If representing this is important for some optimization, we could add
support for available_externally aliases. They would be *required* to
point to a declaration (or available_externally definition).
llvm-svn: 254170
The new function import pass exposed an issue when we import references
to local values on multiple importing passes. They are renamed on each
import pass, and we need to ensure that the already promoted and renamed
references existing in the dest module are correctly identified and
updated so that they aren't spuriously renamed again (due to a perceived
conflict with the newly linked reference).
llvm-svn: 254009
Teresa Johnson