14 Commits

Author SHA1 Message Date
Dan Gohman
546a4623a5 [WebAssembly] Initial linking metadata support
Add support for the new relocations and linking metadata section support in
https://github.com/WebAssembly/tool-conventions/blob/master/Linking.md. In
particular, this allows LLVM to indicate which variable is the stack pointer,
so that it can be linked with other objects.

This also adds support for emitting type relocations for call_indirect
instructions.

Right now, this is mainly tested by using wabt and hexdump to examine the
output on selected testcases. We'll add more tests as the design stablizes
and more of the pieces are in place.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@299141 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-30 23:58:19 +00:00
Derek Schuff
d289ddded8 [WebAssembly] Fix some broken type encodings in wasm binary
A recent change switch the in-memory wasm value types
to be signed integers, but I missing a few cases where
these were being writing to the binary.

Differential Revision: https://reviews.llvm.org/D31014

Patch by Sam Clegg

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@297991 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-16 20:49:48 +00:00
Dan Gohman
8f5a7d69cc [WebAssembly] Add support for using a wasm global for the stack pointer.
This replaces the __stack_pointer variable which was allocated in linear
memory.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296201 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-24 23:46:05 +00:00
Dan Gohman
53ff96ab08 [WebAssembly] Basic support for Wasm object file encoding.
With the "wasm32-unknown-unknown-wasm" triple, this allows writing out
simple wasm object files, and is another step in a larger series toward
migrating from ELF to general wasm object support. Note that this code
and the binary format itself is still experimental.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296190 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-24 23:18:00 +00:00
Dan Gohman
d660a5d68c [WebAssembly] Add skeleton MC support for the Wasm container format
This just adds the basic skeleton for supporting a new object file format.
All of the actual encoding will be implemented in followup patches.

Differential Revision: https://reviews.llvm.org/D26722


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@295803 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-22 01:23:18 +00:00
Derek Schuff
a95cded1a3 [WebAssembly] Emit .import_global assembler directives
Support a new assembler directive, .import_global, to declare imported
global variables (i.e. those with external linkage and no
initializer). The linker turns these into wasm imports.

Patch by Jacob Gravelle

Differential Revision: https://reviews.llvm.org/D26875

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@288296 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-01 00:11:15 +00:00
Dan Gohman
01b89435ec [WebAssembly] Implement more WebAssembly binary encoding.
This changes locals from being declared by the emitLocal hook in
WebAssemblyTargetStreamer, rather than with an instruction. After exploring
the infastructure in LLVM more, this seems to make more sense since
declaring locals doesn't use an encoded opcode.

This also adds more 0xd opcodes, type encodings, and miscellaneous
binary encoding bits.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@285040 91177308-0d34-0410-b5e6-96231b3b80d8
2016-10-24 23:27:49 +00:00
Dan Gohman
12bd3d1963 [WebAssemby] Implement block signatures.
Per spec changes, this implements block signatures, and adds just enough
logic to produce correct block signatures at the ends of functions.

Differential Revision: https://reviews.llvm.org/D25144


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@283503 91177308-0d34-0410-b5e6-96231b3b80d8
2016-10-06 22:29:32 +00:00
Derek Schuff
23429a5af3 [WebAssembly] Support CFI for WebAssembly target
Summary: This patch implements CFI for WebAssembly. It modifies the
LowerTypeTest pass to pre-assign table indexes to functions that are
called indirectly, and lowers type checks to test against the
appropriate table indexes. It also modifies the WebAssembly backend to
support a special ".indidx" assembly directive that propagates the table
index assignments out to the linker.

Patch by Dominic Chen

Differential Revision: https://reviews.llvm.org/D21768

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@277398 91177308-0d34-0410-b5e6-96231b3b80d8
2016-08-01 22:25:02 +00:00
Derek Schuff
561fb73b85 [WebAssembly] Emit type signatures for declared functions
Under emscripten, C code can take the address of a function implemented
in Javascript (which is exposed via an import in wasm). Because imports
do not have linear memory address in wasm, we need to generate a thunk
to be the target of the indirect call; it call the import directly.

To make this possible, LLVM needs to emit the type signatures for these
functions, because they may not be called directly or referred to other
than where the address is taken.

This uses s new .s directive (.functype) which specifies the signature.

Differential Revision: http://reviews.llvm.org/D20891

Re-apply r271599 but instead of bailing with an error when a declared
function has multiple returns, replace it with a pointer argument. Also
add the test case I forgot to 'git add' last time around.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@271703 91177308-0d34-0410-b5e6-96231b3b80d8
2016-06-03 18:34:36 +00:00
Derek Schuff
13e11d741a Revert "[WebAssembly] Emit type signatures for declared functions"
This reverts r271599, it broke the integration tests.
More places than I expected had nontrival return types in imports, or
else the check was wrong.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@271606 91177308-0d34-0410-b5e6-96231b3b80d8
2016-06-02 23:02:44 +00:00
Derek Schuff
1fa45c8fb6 [WebAssembly] Emit type signatures for declared functions
Under emscripten, C code can take the address of a function implemented
in Javascript (which is exposed via an import in wasm). Because imports
do not have linear memory address in wasm, we need to generate a thunk
to be the target of the indirect call; it call the import directly.

To make this possible, LLVM needs to emit the type signatures for these
functions, because they may not be called directly or referred to other
than where the address is taken.

This uses s new .s directive (.functype) which specifies the signature.

Differential Revision: http://reviews.llvm.org/D20891

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@271599 91177308-0d34-0410-b5e6-96231b3b80d8
2016-06-02 21:34:18 +00:00
Dan Gohman
b8e08438aa [WebAssembly] Add a EM_WEBASSEMBLY value, and several bits of code that use it.
A request has been made to the official registry, but an official value is
not yet available. This patch uses a temporary value in order to support
development. When an official value is recieved, the value of EM_WEBASSEMBLY
will be updated.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@257517 91177308-0d34-0410-b5e6-96231b3b80d8
2016-01-12 20:56:01 +00:00
Dan Gohman
f49a61441d [WebAssembly] Introduce a WebAssemblyTargetStreamer class.
Refactor .param, .result, .local, and .endfunc, as directives, using the
proper MCTargetStreamer mechanism, rather than fake instructions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@257511 91177308-0d34-0410-b5e6-96231b3b80d8
2016-01-12 20:30:51 +00:00