Summary:
Adds clang builtins and LLVM intrinsics for these experimental
instructions. They are not implemented in engines yet, but that is ok
because the user must opt into using them by calling the builtins.
Reviewers: aheejin, dschuff
Reviewed By: aheejin
Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D67020
llvm-svn: 370556
Add an WASM_SYMBOL_NO_STRIP flag, so that __attribute__((used)) doesn't
need to imply exporting. When targeting Emscripten, have
WASM_SYMBOL_NO_STRIP imply exporting.
Differential Revision: https://reviews.llvm.org/D62542
llvm-svn: 370415
WebAssembly doesn't support PC relative relocation or relocation
expressions that can't be reduced to single symbol.
The only support for we have for fixups involving two symbols are when
both symbols are defined and withing the same section. In this case
evaluateFixup will already have evaluated to the expression before
calling recordRelocation.
llvm-svn: 369317
A TYPE_INDEX operand (as used by call_indirect) used to be represented
by the InstPrinter as a symbol (e.g. .Ltype_index0@TYPE_INDEX) which
was a bit of a mismatch with the WasmObjectWriter which expects an
unnamed symbol, to receive the signature from and then turn into a
reloc.
There was really no good way to round-trip this information. An earlier
version of this patch tried to attach the signature information using
a .functype, but that ran into trouble when the symbol was re-emitted
without a name. Removing the name was a giant hack also.
The current version changes the assembly syntax to have an inline
signature spec for TYPEINDEX operands that is always unnamed, which
is much more elegant both in syntax and in implementation (as now the
assembler is able to follow the same path as the regular backend)
Reviewers: sbc100, dschuff, aheejin, jgravelle-google, sunfish, tlively
Subscribers: arphaman, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D64758
llvm-svn: 367590
Summary:
We agreed to rename `except_ref` to `exnref` for consistency with other
reference types in
https://github.com/WebAssembly/exception-handling/issues/79. This also
renames WebAssemblyInstrExceptRef.td to WebAssemblyInstrRef.td in order
to use the file for other reference types in future.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, jfb, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D64703
llvm-svn: 366145
Summary:
These are emitted as identifiers by the InstPrinter, so we should
parse them as such. These could potentially clash with symbols of
the same name, but that is out of our (the WebAssembly backend) control.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, aheejin, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D64770
llvm-svn: 366139
Summary:
Before, they were one category of operands which could cause
crashes in non-sensical combinations, e.g. "f32.const symbol".
Now these are forced to be an error.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, aheejin, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D64039
llvm-svn: 365351
Summary:
These are output by clang -S, so can now be roundtripped thru clang.
(partially) fixes: https://bugs.llvm.org/show_bug.cgi?id=34544
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, aheejin, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D63901
llvm-svn: 364658
Summary:
Assembly of atomic.notify has been fixed in r364576, so we can enable
it.
Reviewers: aardappel
Subscribers: dschuff, sbc100, jgravelle-google, sunfish, jfb, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D63898
llvm-svn: 364596
Summary:
- Match the syntax output by InstPrinter.
- Fix it always emitting 0 for align. Had to work around fact that
opcode is not available for GetDefaultP2Align while parsing.
- Updated tests that were erroneously happy with a p2align=0
Fixes https://bugs.llvm.org/show_bug.cgi?id=40752
Reviewers: aheejin, sbc100
Subscribers: jgravelle-google, sunfish, jfb, llvm-commits, dschuff
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D63633
llvm-svn: 364570
Summary:
Implements direct and indirect tail calls enabled by the 'tail-call'
feature in both DAG ISel and FastISel. Updates existing call tests and
adds new tests including a binary encoding test.
Reviewers: aheejin
Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D62877
llvm-svn: 364445
We use both -long-option and --long-option in tests. Switch to --long-option for consistency.
In the "llvm-readelf" mode, -long-option is discouraged as it conflicts with grouped short options and it is not accepted by GNU readelf.
While updating the tests, change llvm-readobj -s to llvm-readobj -S to reduce confusion ("s" is --section-headers in llvm-readobj but --symbols in llvm-readelf).
llvm-svn: 359649
Summary:
This ensures that object files will continue to validate as
WebAssembly modules in the presence of bulk memory operations. Engines
that don't support bulk memory operations will not recognize the
DataCount section and will report validation errors, but that's ok
because object files aren't supposed to be run directly anyway.
Reviewers: aheejin, dschuff, sbc100
Subscribers: jgravelle-google, hiraditya, sunfish, rupprecht, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D60623
llvm-svn: 358315
Summary:
It does not currently make sense to use WebAssembly features in some functions
but not others, so this CL adds an IR pass that takes the union of all used
feature sets and applies it to each function in the module. This allows us to
prevent atomics from being lowered away if some function has opted in to using
them. When atomics is not enabled anywhere, we detect whether there exists any
atomic operations or thread local storage that would be stripped and disallow
linking with objects that contain atomics if and only if atomics or tls are
stripped. When atomics is enabled, mark it as used but do not require it of
other objects in the link. These changes allow libraries that do not use atomics
to be built once and linked into both single-threaded and multithreaded
binaries.
Reviewers: aheejin, sbc100, dschuff
Subscribers: jgravelle-google, hiraditya, sunfish, jfb, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D59625
llvm-svn: 357226
This change implements lowering of references global symbols in PIC
mode.
This change implements lowering of global references in PIC mode using a
new @GOT reference type. @GOT references can be used with function or
data symbol names combined with the get_global instruction. In this case
the linker will insert the wasm global that stores the address of the
symbol (either in memory for data symbols or in the wasm table for
function symbols).
For now I'm continuing to use the R_WASM_GLOBAL_INDEX_LEB relocation
type for this type of reference which means that this relocation type
can refer to either a global or a function or data symbol. We could
choose to introduce specific relocation types for GOT entries in the
future. See the current dynamic linking proposal:
https://github.com/WebAssembly/tool-conventions/blob/master/DynamicLinking.md
Differential Revision: https://reviews.llvm.org/D54647
llvm-svn: 357022
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
Summary:
This is quite minimal so far, introduce them with .section,
fill them with .int8 or .asciz, end with .size
Reviewers: dschuff, sbc100, aheejin
Subscribers: jgravelle-google, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D58660
llvm-svn: 355321
Summary:
In the clang UI, replaces -mthread-model posix with -matomics as the
source of truth on threading. In the backend, replaces
-thread-model=posix with the atomics target feature, which is now
collected on the WebAssemblyTargetMachine along with all other used
features. These collected features will also be used to emit the
target features section in the future.
The default configuration for the backend is thread-model=posix and no
atomics, which was previously an invalid configuration. This change
makes the default valid because the thread model is ignored.
A side effect of this change is that objects are never emitted with
passive segments. It will instead be up to the linker to decide
whether sections should be active or passive based on whether atomics
are used in the final link.
Reviewers: aheejin, sbc100, dschuff
Subscribers: mehdi_amini, jgravelle-google, hiraditya, sunfish, steven_wu, dexonsmith, rupprecht, jfb, jdoerfert, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D58742
llvm-svn: 355112
We record the type of the symbol (event/function/data/global) in the
MCWasmSymbol and so it should always be clear how to handle a relocation
based on the symbol itself.
The exception is a function which still needs the special @TYPEINDEX
then the relocation contains the signature rather than the address
of the functions.
Differential Revision: https://reviews.llvm.org/D58472
llvm-svn: 354697
Summary:
Fixed a bug in the routine in AsmParser that determines whether the
current instruction is a load or a store. Atomic instructions' prefixes
are not `atomic_` but `atomic.`, and all atomic instructions are also
memory instructions. Also fixed the printing format of atomic
instructions to match other memory instructions and added encoding tests
for atomic instructions.
Reviewers: aardappel, tlively
Subscribers: dschuff, sbc100, jgravelle-google, sunfish, jfb, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D58337
llvm-svn: 354419
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
Add a flag to allow symbols to have a wasm import name which differs from the
linker symbol name, allowing the linker to link code using the import_module
attribute.
This is the MC/Object portion of the patch.
Differential Revision: https://reviews.llvm.org/D57632
llvm-svn: 353474
Summary:
There are a few instructions that all map to the same opcode, so
when disassembling, we have to pick one. That was just the first one
before (the except_ref variant in the case of "call"), now it is the
one marked as IsCanonical in tablegen, or failing that, the shortest
name (which is typically the "canonical" one).
Also introduced a canonical "end" instruction for this purpose.
Reviewers: dschuff, tlively
Subscribers: sbc100, jgravelle-google, aheejin, llvm-commits, sunfish
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D57713
llvm-svn: 353131
Aliases of functions are now marked as function symbols even if
they are bitcast to some other other non-function type.
This is important for WebAssembly where object and function
symbols can't alias each other.
Fixes PR38866
Differential Revision: https://reviews.llvm.org/D57538
llvm-svn: 353109
Summary:
These were "boilerplate" that repeated information already present
in .functype and end_function, that needed to be repeated to Please
the particular way our object writing works, and missing them would
generate errors.
Instead, we generate the information for these automatically so the
user can concern itself with writing more canonical wasm functions
that always work as expected.
Reviewers: dschuff, sbc100
Subscribers: jgravelle-google, aheejin, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D57546
llvm-svn: 353067
See https://github.com/WebAssembly/tool-conventions/pull/95.
This is less typing and IMHO more readable, and it also fits with
our naming around the binary format which tends to use the short name.
e.g.
include/llvm/BinaryFormat/Wasm.h
tools/llvm-objdump/WasmDump.cpp
etc..
Differential Revision: https://reviews.llvm.org/D57611
llvm-svn: 353062
Summary:
This switches the EH implementation to the new proposal:
https://github.com/WebAssembly/exception-handling/blob/master/proposals/Exceptions.md
(The previous proposal was
https://github.com/WebAssembly/exception-handling/blob/master/proposals/old/Exceptions.md)
- Instruction changes
- Now we have one single `catch` instruction that returns a except_ref
value
- `throw` now can take variable number of operations
- `rethrow` does not have 'depth' argument anymore
- `br_on_exn` queries an except_ref to see if it matches the tag and
branches to the given label if true.
- `extract_exception` is a pseudo instruction that simulates popping
values from wasm stack. This is to make `br_on_exn`, a very special
instruction, work: `br_on_exn` puts values onto the stack only if it
is taken, and the # of values can vay depending on the tag.
- Now there's only one `catch` per `try`, this patch removes all special
handling for terminate pad with a call to `__clang_call_terminate`.
Before it was the only case there are two catch clauses (a normal
`catch` and `catch_all` per `try`).
- Make `rethrow` act as a terminator like `throw`. This splits BB after
`rethrow` in WasmEHPrepare, and deletes an unnecessary `unreachable`
after `rethrow` in LateEHPrepare.
- Now we stop at all catchpads (because we add wasm `catch` instruction
that catches all exceptions), this creates new
`findWasmUnwindDestinations` function in SelectionDAGBuilder.
- Now we use `br_on_exn` instrution to figure out if an except_ref
matches the current tag or not, LateEHPrepare generates this sequence
for catch pads:
```
catch
block i32
br_on_exn $__cpp_exception
end_block
extract_exception
```
- Branch analysis for `br_on_exn` in WebAssemblyInstrInfo
- Other various misc. changes to switch to the new proposal.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D57134
llvm-svn: 352598
Summary:
objdump was interpreting the function header containing the locals
declaration as instructions. To parse these without injecting target
specific code in objdump, MCDisassembler::onSymbolStart was added to
be implemented by the WebAssembly implemention.
WasmObjectFile now returns a code offset for the "address" of a symbol,
rather than the index. This is also more in-line with what other
targets do.
Also ensured that the AsmParser correctly puts each function
in its own segment to enable this test case.
Reviewers: sbc100, dschuff
Subscribers: jgravelle-google, aheejin, sunfish, rupprecht, llvm-commits
Differential Revision: https://reviews.llvm.org/D56684
llvm-svn: 351460
Thomas Lively