Commit Graph

19 Commits

Author SHA1 Message Date
Sam Clegg e7a60708ff [WebAssembly] Only treat imports/exports as symbols when reading relocatable object files
This change only treats imported and exports functions and globals
as symbol table entries the object has a "linking" section (i.e. it is
relocatable object file).

In this case all globals must be of type I32 and initialized with
i32.const.  This was previously being assumed but not checked for and
was causing a failure on big endian machines due to using the wrong
value of then union.

See: https://bugs.llvm.org/show_bug.cgi?id=34487

Differential Revision: https://reviews.llvm.org/D37497

llvm-svn: 312674
2017-09-06 22:05:41 +00:00
Sam Clegg 13a2e89926 [WebAssembly] Update relocation names to match spec
Summary: See https://github.com/WebAssembly/tool-conventions/blob/master/Linking.md

Differential Revision: https://reviews.llvm.org/D37385

llvm-svn: 312342
2017-09-01 17:32:01 +00:00
Sam Clegg 9c07f94a1f [WebAssembly] Expose the offset of each data segment
Summary:
This allows tools like lld that process relocations
to apply data relocation correctly. This information
is required because relocation are stored as section
offset.

Subscribers: jfb, dschuff, jgravelle-google, aheejin

Differential Revision: https://reviews.llvm.org/D35234

llvm-svn: 307741
2017-07-12 00:24:54 +00:00
Sam Clegg b03c2b4b09 [WebAssembly] Use the correct size for MCFillFragment
Summary: When implementing MCFillFragment, use the size of the fragment,
rather than the size of the section.

Patch by Dan Gohman

Differential Revision: https://reviews.llvm.org/D35090

llvm-svn: 307565
2017-07-10 18:36:34 +00:00
Sam Clegg 5e3d33a781 [WebAssembly] Support weak defined symbols
Model weakly defined symbols as symbols that are both
exports and imported and marked as weak. Local references
to the symbols refer to the import but the linker can
resolve this to the weak export if not strong symbol
is found at link time.

Differential Revision: https://reviews.llvm.org/D35029

llvm-svn: 307348
2017-07-07 02:01:29 +00:00
Sam Clegg 9bf73c078b [WebAssembly] Fix types for address taken functions
Differential Revision: https://reviews.llvm.org/D34966

llvm-svn: 307198
2017-07-05 20:25:08 +00:00
Sam Clegg 8c4baa00de [WebAssembly] MC: Don't generate extra types for weak alias
Previously we were generating a void(void) function type
for a weak alias.  Update the weak-alias test case to
catch this.

Differential Revision: https://reviews.llvm.org/D34734

llvm-svn: 307194
2017-07-05 20:09:26 +00:00
Sam Clegg 9e1ade93a8 [WebAssembly] Add data size and alignement to linking section
The overal size of the data section (including BSS)
is otherwise not included in the wasm binary.

Differential Revision: https://reviews.llvm.org/D34657

llvm-svn: 306459
2017-06-27 20:27:59 +00:00
Sam Clegg 933df2658d [WebAssembly] Add more support for weak symbols
Add weak symbol tests to MC
Add symbol flags to output of `llvm-readobj -t`.

Differential Revision: https://reviews.llvm.org/D34635

llvm-svn: 306330
2017-06-26 21:01:39 +00:00
Sam Clegg 9d24fb7ff3 [WebAssembly] Use __stack_pointer global when writing wasm binary
This ensures that symbolic relocations are generated for stack
pointer manipulations.

These relocations are of type R_WEBASSEMBLY_GLOBAL_INDEX_LEB.
This change also adds support for reading relocations of this
type in WasmObjectFile.cpp.

Since its a globally imported symbol this does mean that
the get_global/set_global instruction won't be valid until
the objects are linked that global used in no longer an
imported global.

Differential Revision: https://reviews.llvm.org/D34172

llvm-svn: 305616
2017-06-16 23:59:10 +00:00
Sam Clegg 7736855dee [WebAssembly] Fix symbol type for addresses of external functions
These symbols were previously not being marked as functions
so were appearing as globals instead, and with the incorrect
relocation type.

Without this fix, objects that take address of external
functions include them as global imports rather than function
imports which then fails at link time.

Differential Revision: https://reviews.llvm.org/D34068

llvm-svn: 305263
2017-06-13 01:42:21 +00:00
Sam Clegg d99f6078e4 [WebAssembly] MC: Fix value of R_WEBASSEMBLY_TABLE_INDEX relocations
Previously we were writing the value function index space
value but for these types of relocations we want to be
writing the table element index space value.

Add a test case for these relocation types that fails
without this change.

Differential Revision: https://reviews.llvm.org/D33962

llvm-svn: 305253
2017-06-12 23:52:44 +00:00
Sam Clegg acd7d2b00b [WebAssembly] MC: Refactor relocation handling
The change cleans up and unifies the handling of relocation
entries in WasmObjectWriter.  Type index relocation no longer
need to be handled separately.

The only externally visible change should be that type
index relocations are no longer grouped at the end.

Differential Revision: https://reviews.llvm.org/D33918

llvm-svn: 304816
2017-06-06 19:15:05 +00:00
Sam Clegg c38e947e50 [WebAssembly] MC: Fix references to undefined externals in data section
Undefined externals don't need to have a size or an offset.
This was broken by r303915.  Added a test for this case.

This fixes the "Compile LLVM Torture (o)" step on the wasm
waterfall.

Differential Revision: https://reviews.llvm.org/D33803

llvm-svn: 304505
2017-06-02 01:05:24 +00:00
Sam Clegg 1c154a6107 [WebAssembly] MC: Include unnamed data when writing wasm files
Also, include global entries for all data symbols, not
just external ones, since these are referenced by the
relocation records.

Add a test case that includes unnamed data.

Differential Revision: https://reviews.llvm.org/D33079

llvm-svn: 303915
2017-05-25 21:08:07 +00:00
Sam Clegg a06de02889 [WebAssembly] Add size of section header to data relocation offsets.
Also, add test for data relocations and fix addend to
be signed.

Subscribers: jfb, dschuff

Differential Revision: https://reviews.llvm.org/D32513

llvm-svn: 301690
2017-04-28 21:22:38 +00:00
Sam Clegg ff0730b3fc [WebAssembly] Write initial memory in pages not bytes
Subscribers: jfb, dschuff

Differential Revision: https://reviews.llvm.org/D32660

llvm-svn: 301687
2017-04-28 21:12:09 +00:00
Sam Clegg 10545c9c24 [WebAssembly] Add some tests for wasm MC layer
Subscribers: jfb, dschuff

Differential Revision: https://reviews.llvm.org/D32558

llvm-svn: 301606
2017-04-28 00:36:36 +00:00
Dan Gohman 7ea5adfff4 [WebAssembly] Implement the wasm binary container header.
Also, update the version number to 0x1, which is what engines are now
expecting.

llvm-svn: 295860
2017-02-22 18:50:20 +00:00