Commit Graph

19 Commits

Author SHA1 Message Date
Sam Clegg accad76c14 [lld][WebAssembly] Fix handling of comdat functions in init array.
When hidden symbols are discarded by comdat rules we still want to
create a local defined symbol, otherwise `Symbol::isDiscarded()` relies
on begin able to check `getChunk->discarded`.

This is a followup on rL362769. The comdat.ll test was previously GC'ing
the `__wasm_call_ctors` functions so `do_init` was not actually being
included in the link.  Once that function was included in triggered the
crash bug that this change addresses.

Fixes: https://github.com/emscripten-core/emscripten/issues/8981

Differential Revision: https://reviews.llvm.org/D64872

llvm-svn: 366358
2019-07-17 18:43:36 +00:00
Sam Clegg fd54fa5d72 [WebAssembly] Fix for discarded init functions
When a function is excluded via comdat we shouldn't add it to the
final list of init functions.

Differential Revision: https://reviews.llvm.org/D62983

llvm-svn: 362769
2019-06-07 06:00:46 +00:00
Sam Clegg 7d4ec5af6c [WebAssembly] Don't export __data_end and __heap_base by default.
These can still be exported via --export if needed.

Differential Revision: https://reviews.llvm.org/D62744

llvm-svn: 362276
2019-05-31 22:51:59 +00:00
Sam Clegg 0e6b42f5eb [WebAssebmly] Allow __wasm_call_ctors to be GC'ed
Differential Revision: https://reviews.llvm.org/D58806

llvm-svn: 355240
2019-03-01 22:35:47 +00:00
Thomas Lively 2e1504091e [WebAssembly] Update MC for bulk memory
Summary:
Rename MemoryIndex to InitFlags and implement logic for determining
data segment layout in ObjectYAML and MC. Also adds a "passive" flag
for the .section assembler directive although this cannot be assembled
yet because the assembler does not support data sections.

Reviewers: sbc100, aardappel, aheejin, dschuff

Subscribers: jgravelle-google, hiraditya, sunfish, rupprecht, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D57938

llvm-svn: 354397
2019-02-19 22:56:19 +00:00
Sam Clegg 305b0343ce [WebAssembly] Add --[no]-export-dynamic to replace --export-default
In a very recent change I introduced a --no-export-default flag
but after conferring with others it seems that this feature already
exists in gnu GNU ld and lld in the form the --export-dynamic flag
which is off by default.

This change replaces export-default with export-dynamic and also
changes the default to match the traditional linker behaviour.

Now, by default, only the entry point is exported.  If other symbols
are required by the embedder then --export-dynamic or --export can
be used to export all visibility hidden symbols or individual
symbols respectively.

This change touches a lot of tests that were relying on symbols
being exported by default.  I imagine it will also effect many
users but do think the change is worth it match of the traditional
behaviour and flag names.

Differential Revision: https://reviews.llvm.org/D52587

llvm-svn: 343265
2018-09-27 21:06:25 +00:00
Sam Clegg 262e09018b [WebAssembly] Remove final -wasm component of target triple. NFC.
This has been the default for a while now.

llvm-svn: 332009
2018-05-10 17:59:41 +00:00
Sam Clegg 752494bfe3 [WebAssembly] Check function signatures by default
But only produce a warning (for now) unless --fatal-warnings
is passed.

Differential Revision: https://reviews.llvm.org/D46484

llvm-svn: 331574
2018-05-05 01:23:07 +00:00
Nicholas Wilson 5639da89a9 [WebAssembly] Reorder synthetic functions to come first
This matches the existing ordering that's been there for globals
for a while (__stack_pointer coming first).

Differential Revision: https://reviews.llvm.org/D44333

llvm-svn: 327286
2018-03-12 15:44:07 +00:00
Nicholas Wilson f2f6d5e03b [WebAssembly] Export non-hidden defined data symbols via wasm globals
This fixes a TODO introduced in rLLD325861.

Differential Revision: https://reviews.llvm.org/D43930

llvm-svn: 326581
2018-03-02 14:51:36 +00:00
Nicholas Wilson 4cdf5b8fa0 [WebAssembly] Reorder exports to match symbol table order
This fixes a TODO introduced in rLLD325861.

Differential Revision: https://reviews.llvm.org/D43877

llvm-svn: 326424
2018-03-01 09:38:02 +00:00
Sam Clegg 45f984e625 [WebAssembly] Remove unneeded --no-gc-sections flag from tests. NFC.
Differential Revision: https://reviews.llvm.org/D43889

llvm-svn: 326356
2018-02-28 19:40:03 +00:00
Rui Ueyama f05124e60c Use wasm-ld instead of "lld -flavor wasm".
Invoking lld as ld.lld, ld.ld64, lld-link or wasm-ld is preferred
than invoking lld as lld and pass an -flavor option. We have "lld"
file mostly for historical reasons.

Differential Revision: https://reviews.llvm.org/D43407

llvm-svn: 325405
2018-02-16 22:58:02 +00:00
Sam Clegg 37a4a8a4b1 [WebAssembly] Add __data_end link-sythentic symbol.
This is similar to _end (See https://linux.die.net/man/3/edata for more)
but using our own unique name since our use cases will most likely be
different and we want to keep our options open WRT to memory layout.

This change will allow is to remove the DataSize from the linking
metadata section which is currently being used by emscripten to derive
the end of the data.

Differential Revision: https://reviews.llvm.org/D42867

llvm-svn: 324443
2018-02-07 03:04:53 +00:00
Sam Clegg 279c850cf2 [WebAssembly] Fix signature mismatches in test code
Pass --check-signatures to test executions of lld and
fix resulting errors.

Differential Revision: https://reviews.llvm.org/D42661

llvm-svn: 324042
2018-02-02 00:30:03 +00:00
Sam Clegg 0362633fd2 [WebAssembly] Add support for --gc-sections
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
2018-01-31 01:45:47 +00:00
Sam Clegg 70683b2f75 [WebAssembly] Use inline target tripple in test cases
This is somewhat preferable since (in many cases) it allows llc
to be run directly on the .ll files without having to pass the
`-mtriple` argument.

Differential Revision: https://reviews.llvm.org/D42438

llvm-svn: 323299
2018-01-24 03:29:47 +00:00
Sam Clegg 51bcdc2d49 [WebAssembly] Define __heap_base global
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
2018-01-17 01:34:31 +00:00
Sam Clegg e0f6fcd0d9 [WebAssembly] Add COMDAT support
See https://bugs.llvm.org/show_bug.cgi?id=35533, and D40844

Things covered:
* Removing duplicate data segments (as determined by COMDATs emitted
  by the frontend)
* Removing duplicate globals and functions in COMDATs
* Checking that each time a COMDAT is seen it has the same symbols
  as at other times (ie it's a stronger check than simply giving all
  the symbols in the COMDAT weak linkage)

Patch by Nicholas Wilson!

Differential Revision: https://reviews.llvm.org/D40845

llvm-svn: 322415
2018-01-12 22:25:17 +00:00