In this initial version we only GC symbols with `hidden` visibility since
other symbols we export to the embedder.
We could potentially modify this the future and only use symbols
explicitly passed via `--export` as GC roots.
This version of the code only does GC of data and code. GC for the
types section is coming soon.
Differential Revision: https://reviews.llvm.org/D42511
llvm-svn: 323842
This was added to mimic ELF, but maintaining it has cost
and we currently don't have any use for it outside of the
test code.
Differential Revision: https://reviews.llvm.org/D42324
llvm-svn: 323154
Its much easier to export it via setHidden(false), now that
that is a thing.
As a side effect the start function is not longer always exports first
(becuase its being exported just like all the other function).
Differential Revision: https://reviews.llvm.org/D42321
llvm-svn: 323025
This code was needed back when we were not able to write
out the synthetic symbol for main.
Add tests to make sure we can handle this now.
Differential Revision: https://reviews.llvm.org/D42322
llvm-svn: 323020
This is an immutable exported global representing
the start of the heap area. It is a page aligned.
Differential Revision: https://reviews.llvm.org/D42030
llvm-svn: 322609
This is used by __cxa_ataxit to determine the currently
executing DLL. Once we fully support DLLs this will need
to be set to some address within the DLL.
The ELF linker added support for this symbol here:
https://reviews.llvm.org/D33856
Differential Revision: https://reviews.llvm.org/D42024
llvm-svn: 322606
This is useful for emscripten or other tools that want to
selectively exports symbols without necessarily changing the
source code.
Differential Revision: https://reviews.llvm.org/D42003
llvm-svn: 322408
This allows libraries to supply a list of symbols which are
allowed to be undefined at link time (i.e. result in imports).
This method replaces the existing mechanism (-allow-undefined-file)
used by the clang driver to allow undefined symbols in libc.
For more on motivation for this see:
https://github.com/WebAssembly/tool-conventions/issues/35
In the long run we hope to remove this features and instead
include this information in the object format itself.
Differential Revision: https://reviews.llvm.org/D41922
llvm-svn: 322320
This adds a `--no-entry` argument to wasm LLD used to
suppress the default `_start` entry point.
Patch by Nicholas Wilson!
Differential Revision: https://reviews.llvm.org/D40725
llvm-svn: 320167
Adds a new argument to wasm-lld, `--undefined`, with
similar semantics to the ELF linker. It pulls in symbols
from files contained within a `.a` archive, forcing them
to be included even if the translation unit would not
otherwise be pulled in.
Patch by Nicholas Wilson
Differential Revision: https://reviews.llvm.org/D40724
llvm-svn: 320004
This change cleans up the way wasm exports and globals
are generated, particualrly for -r/--relocatable where
globals need to be created and exported in order for
output relocations which reference them.
Remove the need for a per file GlobalIndexOffset and
instead set the output index for each symbol directly.
This simplifies the code in several places.
Differential Revision: https://reviews.llvm.org/D40859
llvm-svn: 320001
This line was mistakenly deleted in rL319813
Add a test for stackpointer relocations.
Differential Revision: https://reviews.llvm.org/D40847
llvm-svn: 319828
This is part of larger change to add synthetic symbols
for section start/end points and init/fini_array:
https://reviews.llvm.org/D40760
Allows synthetic global symbols to have an explicitly set
virtual address.
Differential Revision: https://reviews.llvm.org/D40843
llvm-svn: 319813
This is a small change I split of from a larger one
that simplifies the condition that need to be checked
when decided if we need to emit relocation and all the
things they depend on (symbols, etc).
Differential Revision: https://reviews.llvm.org/D40825
llvm-svn: 319789
This change allows checking of function signatures but
does not yes enable it by default. In this mode, linking
two objects that were compiled with a different signatures
for the same function will produce a link error.
New options for enabling and disabling this feature have been
added: (--check-signatures/--no-check-signatures).
Differential Revision: https://reviews.llvm.org/D40371
llvm-svn: 319396
This linker backend is still a work in progress but is
enough to link simple programs including linking against
library archives.
Differential Revision: https://reviews.llvm.org/D34851
llvm-svn: 318539
Sam Clegg