Commit Graph

34 Commits

Author SHA1 Message Date
Sam Clegg 15006469bf [lld][WebAssembly] Fix __start/__stop symbols when combining input segments
We should be generating one __start/__stop pair per output segment
not per input segment.  The test wasn't catching this because it was
only linking a single object file.

Fixes PR41565

Differential Revision: https://reviews.llvm.org/D64148

llvm-svn: 365308
2019-07-08 10:35:08 +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
Thomas Lively f6f4f84378 [WebAssembly] Target features section
Summary:
Implements a new target features section in assembly and object files
that records what features are used, required, and disallowed in
WebAssembly objects. The linker uses this information to ensure that
all objects participating in a link are feature-compatible and records
the set of used features in the output binary for use by optimizers
and other tools later in the toolchain.

The "atomics" feature is always required or disallowed to prevent
linking code with stripped atomics into multithreaded binaries. Other
features are marked used if they are enabled globally or on any
function in a module.

Future CLs will add linker flags for ignoring feature compatibility
checks and for specifying the set of allowed features, implement using
the presence of the "atomics" feature to control the type of memory
and segments in the linked binary, and add front-end flags for
relaxing the linkage policy for atomics.

Reviewers: aheejin, sbc100, dschuff

Subscribers: jgravelle-google, hiraditya, sunfish, mgrang, jfb, jdoerfert, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D59173

llvm-svn: 356610
2019-03-20 20:26:45 +00:00
Sam Clegg 6540e57002 [WebAssembly] Don't generate invalid modules when function signatures mismatch
Previously we could emit a warning and generate a potentially invalid
wasm module (due to call sites and functions having conflicting
signatures). Now, rather than create invalid binaries we handle such
cases by creating stub functions containing unreachable, effectively
turning these into runtime errors rather than validation failures.

Differential Revision: https://reviews.llvm.org/D57909

llvm-svn: 354528
2019-02-20 23:19:31 +00:00
Sam Clegg 79e33171d6 [WebAssembly] Update relocation naming to match llvm change. NFC.
Differential Revision: https://reviews.llvm.org/D57698

llvm-svn: 353066
2019-02-04 17:49:33 +00:00
Sam Clegg 6320efb4ed [WebAssembly] Store section alignment as a power of 2
This change bumps for version number of the wasm object file
metadata.

See https://github.com/WebAssembly/tool-conventions/pull/92

Differential Revision: https://reviews.llvm.org/D56762

llvm-svn: 351287
2019-01-16 01:43:21 +00:00
Heejin Ahn e915a71f18 [WebAssembly] Add support for the event section
Summary:
This adds support for the 'event section' specified in the exception
handling proposal.

Wasm exception handling binary model spec:
https://github.com/WebAssembly/exception-handling/blob/master/proposals/Exceptions.md#changes-to-the-binary-model

Reviewers: sbc100, ruiu

Subscribers: dschuff, jgravelle-google, sunfish, llvm-commits

Differential Revision: https://reviews.llvm.org/D54875

llvm-svn: 348703
2018-12-08 06:17:43 +00:00
Sam Clegg 2df314d17f [WebAssembly] Fix archive member display in error messages
Add a test for this by causing a symbol collision
between archive members.

Differential Revision: https://reviews.llvm.org/D49343

llvm-svn: 337426
2018-07-18 21:46:09 +00:00
Sam Clegg e16a7d3faf [WebAssembly] Minor cleanup to test inputs. NFC.
Update load-undefined.test such that it doesn't rely on
ret32 and ret64 having default visibility.

Split out from: https://reviews.llvm.org/D48394

Differential Revision: https://reviews.llvm.org/D48403

llvm-svn: 335187
2018-06-20 22:52:33 +00:00
Sam Clegg 610ac3bd42 [WebAssembly] Fix crash when relocation synbol is not live
When a symbol is GC'd it can still be references by relocations
in the debug sections, but such symbols are not assigned virtual
addresses.

This change adds a new global data symbol which gets GC'd but
should still appears in the output debug info, albeit with a 0
address.

Fixes 37555

Differential Revision: https://reviews.llvm.org/D47238

llvm-svn: 333047
2018-05-23 01:38:00 +00:00
Sam Clegg 65d6380cd6 [WebAssembly] Allow signautre of entry function to be flexible
Since we a no longer using this function for the wasm start
section we don't actually care what its signature is.

Differential Revision: https://reviews.llvm.org/D46594

llvm-svn: 332308
2018-05-14 23:01:16 +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
Benjamin Kramer 9a85470a57 [wasm] Update test for variables->retainedNodes rename.
This fixes the test after LLVM r331841.

llvm-svn: 331862
2018-05-09 10:09:23 +00:00
Sam Clegg d177ab2a5f [WebAssembly] Add support for debug (DWARF) sections
Specifically add support for custom sections that contain
relocations, and for the two new relocation types needed
by DWARF sections.

See: https://reviews.llvm.org/D44184

Patch by Yury Delendik!

Differential Revision: https://reviews.llvm.org/D44184

llvm-svn: 331566
2018-05-04 23:14:42 +00:00
Sam Clegg 2b8b179867 [WebAssembly] Add version to linking section (to match llvm-side change)
Differential Revision: https://reviews.llvm.org/D46070

llvm-svn: 330971
2018-04-26 18:17:21 +00:00
Nicholas Wilson 358af38d37 [WebAssembly] Implement -print-gc-sections, to better test GC of globals
Differential Revision: https://reviews.llvm.org/D44311

llvm-svn: 330456
2018-04-20 17:28:12 +00:00
Nicholas Wilson a1e299f58b [WebAssembly] Implement GC for imports
Differential Revision: https://reviews.llvm.org/D44313

llvm-svn: 330454
2018-04-20 17:18:06 +00:00
Sam Clegg 80ba43872e [WebAssembly] Add support for custom sections
Copy user-defined custom sections into the output, concatenating
sections with the same name.

Differential Revision: https://reviews.llvm.org/D45340

llvm-svn: 329717
2018-04-10 16:12:49 +00:00
Sam Clegg c7e885b52a [WebAssembly] Check signatures of weakly defined funtions too
Subscribers: jfb, dschuff, jgravelle-google, aheejin, sunfish, llvm-commits

Differential Revision: https://reviews.llvm.org/D43492

llvm-svn: 325598
2018-02-20 17:20:44 +00:00
Sam Clegg 5489b9f1cf [WebAssembly] Reduce redundancy in tests
Add a simple start entry point input file and have the tests
reference that rather than duplicating these.

This allows more tests to be pure `.test` files rather than
`.ll`.

Differential Revision: https://reviews.llvm.org/D42662

llvm-svn: 323838
2018-01-31 00:13:26 +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 ab604a9882 [WebAssembly] Update to match llvm changes to TABLE relocations
TABLE relocations now store the function that is being refered
to indirectly.

See rL323165.

Also extend the call-indirect.ll a little.

Based on a patch by Nicholas Wilson!

llvm-svn: 323168
2018-01-23 01:25:56 +00:00
Sam Clegg d3052d5522 [WebAssembly] Add missing function exports and SYM_INFO to --relocatable output
When writing relocatable files we were exporting for all globals
(including file-local syms), but not for functions. Oops. To be
consistent with non-relocatable output, all symbols (file-local
and global) should be exported. Any symbol targetted by further
relocations needs to be exported. The lack of local function
exports was just an omission, I think.

Second bug: Local symbol names can collide, causing an illegal
Wasm file to be generated! Oops again. This only previously affected
producing relocatable output from two files, where each had a global
with the same name. We need to "budge" the symbol names for locals
that are exported on relocatable output.

Third bug: LLD's relocatable output wasn't writing out any symbol
flags! Thus the local globals weren't being marked as local, and
the hidden flag was also stripped...

Added tests to exercise colliding local names with/without
relocatable flag

Patch by Nicholas Wilson!

Differential Revision: https://reviews.llvm.org/D42105

llvm-svn: 322908
2018-01-18 23:40:49 +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
Sam Clegg 5068685678 [WebAssembly] Create synthetic __wasm_call_ctors function
This change create a new synthetic function in the final
output binary which calls the static constructors in sequence.

See: https://github.com/WebAssembly/tool-conventions/issues/25

Differential Revision: https://reviews.llvm.org/D41893

llvm-svn: 322388
2018-01-12 18:35:13 +00:00
Sam Clegg 5cfffbc875 [WebAssembly] Increase test coverage for weak aliases
LLVM-side is now fixed

Differential Revision: https://reviews.llvm.org/D41511

llvm-svn: 321385
2017-12-22 20:35:19 +00:00
Sam Clegg 86109f63c8 [WebAssembly] Add extra test for weak global symbols
Summary:
Currently the test only checks behaviour for weak function symbols.

Should be good to merge straight away?

Reviewers: sbc100

Reviewed By: sbc100

Subscribers: jfb, dschuff, jgravelle-google, aheejin, sunfish, llvm-commits

Differential Revision: https://reviews.llvm.org/D41449

llvm-svn: 321308
2017-12-21 21:15:00 +00:00
Sam Clegg c6e4d73f31 [WebAssembly] Improve weak alias tests cases
Based on: https://github.com/WebAssembly/tool-conventions/issues/34

Currently weak-alias-overide.ll exhibits incorrect
behaviour in that call_direct() calls the wrong function.

Differential Revision: https://reviews.llvm.org/D41460

llvm-svn: 321241
2017-12-21 02:30:09 +00:00
Sam Clegg 0d0dd39159 [WebAssembly] Add support for writing out init functions in linking section
This change add support for init functions in the linking
section, but only in -r/--relocatable mode.

Differential Revision: https://reviews.llvm.org/D41375

llvm-svn: 321088
2017-12-19 17:09:45 +00:00
Sam Clegg 2e25e896fb [WebAssembly] Improve wasm test cases
Add test for weakly defined symbols with the same name

Improve test for call-indirect to include the same call in two
different objects. This lays the ground work to improve the
output via de-duplicating the indirect call table:
   https://reviews.llvm.org/D40989

Also make all tests consistently pass -mtriple rather than
declaring in the sources.

Differential Revision: https://reviews.llvm.org/D41024

llvm-svn: 320172
2017-12-08 18:37:44 +00:00
Sam Clegg 4b27c0554c Reland "[WebAssembly] Add support for visibility flag""
Subscribers: jfb, dschuff, jgravelle-google, aheejin, sunfish

Differential Revision: https://reviews.llvm.org/D40773

llvm-svn: 319627
2017-12-03 02:38:04 +00:00
Heejin Ahn 675147b54d [WebAssembly] Revert r319592 "Add support for visibility flag"
r319488 reportedly broke one of LLVM bots (ubuntu-gcc7.1-werror), and this patch
depends on that patch.
See http://lab.llvm.org:8011/builders/ubuntu-gcc7.1-werror/builds/3369 for
details.

llvm-svn: 319603
2017-12-02 02:05:50 +00:00
Sam Clegg e7487e4c92 [WebAssembly] Add support for visibility flag
Patch by Nicholas Wilson

Differential Revision: https://reviews.llvm.org/D40690

llvm-svn: 319592
2017-12-01 22:37:25 +00:00
Sam Clegg c94d393ad5 [WebAssembly] Initial wasm linker implementation
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
2017-11-17 18:14:09 +00:00