The indirect function table, synthesized by the linker, is needed if and
only if there are TABLE_INDEX relocs.
Differential Revision: https://reviews.llvm.org/D91637
When we produce an YAML output, we also print leading zeroes currently.
An output might look like this:
```
- Name: .dynsym
Type: SHT_DYNSYM
Address: 0x0000000000001000
EntSize: 0x0000000000000018
```
There are probably no reason to print leading zeroes.
It just makes harder to read values. This patch stops printing them.
The output becomes like:
```
- Name: .dynsym
Type: SHT_DYNSYM
Address: 0x1000
EntSize: 0x18
```
This affects obj2yaml mostly, but also dsymutil and llvm-xray tools output.
Differential revision: https://reviews.llvm.org/D90930
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
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:
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
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
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
MCContext does not destroy MCSymbols on shutdown. So, rather than putting
SmallVectors (which may heap-allocate) inside MCSymbolWasm, use unowned pointer
to a WasmSignature instead. The signatures are now owned by the AsmPrinter.
Also uses WasmSignature instead of param and result vectors in TargetStreamer,
and leaves some TODOs for further simplification.
Differential Revision: https://reviews.llvm.org/D52580
llvm-svn: 343733
Summary: The final -wasm component has been the default for some time now.
Subscribers: jfb, dschuff, jgravelle-google, eraman, aheejin, JDevlieghere, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D46342
llvm-svn: 332007
This adds a wasm-import-module function attribute and a .import_module
assembler directive, for specifying module import names for WebAssembly.
Currently these may only be used for function symbols; global variables
may be considered in the future.
WebAssembly has a two-level namespace scheme for symbols, and it's
normally the linker's job to assign the module name, which is the
first-level name. The attributes here allow users to specify their
own module names explicitly, which is useful for tools generating
bindings to modules defined in other languages.
This feature is not fully usable yet. It will evolve along with the
ongoing symbol table and lld changes.
Differential Revision: https://reviews.llvm.org/D42520
llvm-svn: 324778
This matches the CodeGen tests and makes it a little easy
to run these from the command line manually.
Differential Revision: https://reviews.llvm.org/D42440
llvm-svn: 323275
Relocations of type R_WEBASSEMBLY_TABLE_INDEX represent places
where the table index for a given function is needed. While the
value stored in this location is a table index, the index in
the relocation entry itself is a function index (the index of
the function which is to be called indirectly).
This is how is was spec'd originally but the LLVM implementation
didn't do this. This makes things a little simpler in the linker
since the table in the input file can essentially be ignored that
the output table can be created purely based on these relocations.
Patch by Nicholas Wilson!
Differential Revision: https://reviews.llvm.org/D42080
llvm-svn: 323165
Summary:
For consistency with the output of lld.
This is useful in runnable binaries as can them be sure the
null function pointer will never be a valid argument
call_indirect.
Subscribers: jfb, dschuff, jgravelle-google, aheejin, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D42284
llvm-svn: 322978
Instead of having .o files contain linear-memory and function table
definitions, use imports. This is more consistent with the stack pointer
being imported, and it's consistent with the linker being the one to
decide whether linear memory and function table are imported or defined
in the linked output. This implements tool-conventions #23.
Differential Revision: https://reviews.llvm.org/D40875
llvm-svn: 319989
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
Andy Wingo