Commit Graph

25 Commits

Author SHA1 Message Date
Thomas Lively 393d0f799f [WebAssembly] Allow multivalue signatures in object files
Summary:
Also changes the wasm YAML format to reflect the possibility of having
multiple return types and to put the returns after the params for
consistency with the binary encoding.

Reviewers: aheejin, sbc100

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

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69156

llvm-svn: 375283
2019-10-18 20:27:30 +00:00
Thomas Lively 190dacc3cc [WebAssembly] Elide data segments for .bss sections
Summary:
WebAssembly memories are zero-initialized, so when module does not
import its memory initializing .bss sections is guaranteed to be a
no-op. To reduce binary size and initialization time, .bss sections
are simply not emitted into the final binary unless the memory is
imported.

Reviewers: sbc100

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

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68965

llvm-svn: 374940
2019-10-15 19:05:11 +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 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 89e4dcb4be [WebAssembly] Fix crash with LTO + relocatable + undefined symbols
Change the way we create the symbol table to be closer to how its done
on ELF.  Now the output symbol table matches the internal symtab order
and includes local and undefined symbols.

Fixes PR40204

Differential Revision: https://reviews.llvm.org/D56947

llvm-svn: 352645
2019-01-30 18:55:15 +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
Thomas Lively 25ff893712 [WebAssembly] Instruction renaming
Summary: Associated with D56338.

Reviewers: aheejin, aardappel

Subscribers: dschuff, sbc100, jgravelle-google, sunfish, llvm-commits

Differential Revision: https://reviews.llvm.org/D56339

llvm-svn: 350610
2019-01-08 06:25:55 +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 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
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 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 99eb42c0c5 [WebAssembly] Remove DataSize from linking metadata
This means we don't need to write the linking metadata section
at all for executable (non-relocatable) output.

Differential Revision: https://reviews.llvm.org/D42869

llvm-svn: 326268
2018-02-27 23:58:03 +00:00
Sam Clegg 9310297438 [WebAssembly] Add explicit symbol table
This change modified lld to in response the llvm change which
moved to a more explicit symbol table in the object format.

Based on patches by Nicholas Wilson:
 1. https://reviews.llvm.org/D41955
 2. https://reviews.llvm.org/D42585

The primary difference that we see in the test output is that
for relocatable (-r) output we now have symbol table which
replaces exports/imports and globals.

See: https://github.com/WebAssembly/tool-conventions/issues/38
Differential Revision: https://reviews.llvm.org/D43264

llvm-svn: 325861
2018-02-23 05:08:53 +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 48bbd63fea [WebAssembly] Always start table index at 1, even for relocatable output
Previously llvm was using 0 as the first table index for wasm object
files but now that has switched to 1 we can have the output of lld
do the same and simplify the code.

Patch by Nicholas Wilson!

Differential Revision: https://reviews.llvm.org/D42096

llvm-svn: 323378
2018-01-24 21:37:30 +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
Rui Ueyama b9b1a522ea Remove trailing whitespace.
llvm-svn: 323287
2018-01-24 00:22:53 +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