[WebAssembly] Fix catch block type in wasm64 (#124381)

`try_table`'s `catch` or `catch_ref`'s target block's return type should
be `i64` and `(i64, exnref)` in case of wasm64.

[WebAssembly] Remove unused includes (NFC) (#116318)

Identified with misc-include-cleaner.

[WebAssembly] Add assembly support for final EH proposal (#107917)

This adds the basic assembly generation support for the final EH
proposal, which was newly adopted in Sep 2023 and advanced into P

[WebAssembly] Add assembly support for final EH proposal (#107917)

This adds the basic assembly generation support for the final EH
proposal, which was newly adopted in Sep 2023 and advanced into Phase 4
in Jul 2024:

https://github.com/WebAssembly/exception-handling/blob/main/proposals/exception-handling/Exceptions.md

This adds support for the generation of new `try_table` and `throw_ref`
instruction in .s asesmbly format. This does NOT yet include
- Block annotation comment generation for .s format
- .o object file generation
- .s assembly parsing
- Type checking (AsmTypeCheck)
- Disassembler
- Fixing unwind mismatches in CFGStackify

These will be added as follow-up PRs.

---

The format for `TRY_TABLE`, both for `MachineInstr` and `MCInst`, is as
follows:
```
TRY_TABLE type number_of_catches catch_clauses*
```
where `catch_clause` is
```
catch_opcode tag+ destination
```
`catch_opcode` should be one of 0/1/2/3, which denotes
`CATCH`/`CATCH_REF`/`CATCH_ALL`/`CATCH_ALL_REF` respectively. (See
`BinaryFormat/Wasm.h`) `tag` exists when the catch is one of `CATCH` or
`CATCH_REF`.
The MIR format is printed as just the list of raw operands. The
(stack-based) assembly instruction supports pretty-printing, including
printing `catch` clauses by name, in InstPrinter.

In addition to the new instructions `TRY_TABLE` and `THROW_REF`, this
adds four pseudo instructions: `CATCH`, `CATCH_REF`, `CATCH_ALL`, and
`CATCH_ALL_REF`. These are pseudo instructions to simulate block return
values of `catch`, `catch_ref`, `catch_all`, `catch_all_ref` clauses in
`try_table` respectively, given that we don't support block return
values except for one case (`fixEndsAtEndOfFunction` in CFGStackify).
These will be omitted when we lower the instructions to `MCInst` at the
end.

LateEHPrepare now will have one more stage to covert
`CATCH`/`CATCH_ALL`s to `CATCH_REF`/`CATCH_ALL_REF`s when there is a
`RETHROW` to rethrow its exception. The pass also converts `RETHROW`s
into `THROW_REF`. Note that we still use `RETHROW` as an interim pseudo
instruction until we convert them to `THROW_REF` in LateEHPrepare.

CFGStackify has a new `placeTryTableMarker` function, which places
`try_table`/`end_try_table` markers with a necessary `catch` clause and
also `block`/`end_block` markers for the destination of the `catch`
clause.

In MCInstLower, now we need to support one more case for the multivalue
block signature (`catch_ref`'s destination's `(i32, exnref)` return
type).

InstPrinter has a new routine to print the `catch_list` type, which is
used to print `try_table` instructions.

The new test, `exception.ll`'s source is the same as
`exception-legacy.ll`, with the FileCheck expectations changed. One
difference is the commands in this file have `-wasm-enable-exnref` to
test the new format, and don't have `-wasm-disable-explicit-locals
-wasm-keep-registers`, because the new custom InstPrinter routine to
print `catch_list` only works for the stack-based instructions (`_S`),
and we can't use `-wasm-keep-registers` for them.

As in `exception-legacy.ll`, the FileCheck lines for the new tests do
not contain the whole program; they mostly contain only the control flow
instructions for readability.

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[WebAssembly] Allocate MCSymbolWasm data on MCContext (#85866)

Fixes #85578, a use-after-free caused by some `MCSymbolWasm` data being
freed too early.

Previously, `WebAssemblyAsmParser` owned t

[WebAssembly] Allocate MCSymbolWasm data on MCContext (#85866)

Fixes #85578, a use-after-free caused by some `MCSymbolWasm` data being
freed too early.

Previously, `WebAssemblyAsmParser` owned the data that is moved to
`MCContext` by this PR, which caused problems when handling module ASM,
because the ASM parser was destroyed after parsing the module ASM, but
the symbols persisted.

The added test passes locally with an LLVM build with AddressSanitizer
enabled.

Implementation notes:

* I've called the added method
<code>allocate<b><i>Generic</i></b>String</code> and added the second
paragraph of its documentation to maybe guide people a bit on when to
use this method (based on my (limited) understanding of the `MCContext`
class). We could also just call it `allocateString` and remove that
second paragraph.
* The added `createWasmSignature` method does not support taking the
return and parameter types as arguments: Specifying them afterwards is
barely any longer and prevents them from being accidentally specified in
the wrong order.
* This removes a _"TODO: Do the uniquing of Signatures here instead of
ObjectFileWriter?"_ since the field it's attached to is also removed.
Let me know if you think that TODO should be preserved somewhere.

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[WebAssembly] Create separation between MC and CodeGen layers

Move WebAssemblyUtilities from Utils to the CodeGen library. It
primarily deals in MIR layer types, so it really lives in the CodeGen
li

[WebAssembly] Create separation between MC and CodeGen layers

Move WebAssemblyUtilities from Utils to the CodeGen library. It
primarily deals in MIR layer types, so it really lives in the CodeGen
library.

Move a variety of other things around to try create better separation.

See issue #64166 for more info on layering.

Move llvm/include/CodeGen/WasmAddressSpaces.h back to
llvm/lib/Target/WebAssembly/Utils.

Differential Revision: https://reviews.llvm.org/D156472

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[WebAssembly] Use ArrayRef/SmallVectorImpl in parameters (NFC)

It is recommended to use `SmallVectorImpl`/`ArrayRef` over
`SmallVector<TypeName, N>` for function parameters:
https://llvm.org/docs/Pr

[WebAssembly] Use ArrayRef/SmallVectorImpl in parameters (NFC)

It is recommended to use `SmallVectorImpl`/`ArrayRef` over
`SmallVector<TypeName, N>` for function parameters:
https://llvm.org/docs/ProgrammersManual.html#llvm-adt-smallvector-h

Reviewed By: dschuff

Differential Revision: https://reviews.llvm.org/D146841

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[MC] Make more use of MCInstrDesc::operands. NFC.

Change MCInstrDesc::operands to return an ArrayRef so we can easily use
it everywhere instead of the (IMHO ugly) opInfo_begin and opInfo_end.
A futu

[MC] Make more use of MCInstrDesc::operands. NFC.

Change MCInstrDesc::operands to return an ArrayRef so we can easily use
it everywhere instead of the (IMHO ugly) opInfo_begin and opInfo_end.
A future patch will remove opInfo_begin and opInfo_end.

Also use it instead of raw access to the OpInfo pointer. A future patch
will remove this pointer.

Differential Revision: https://reviews.llvm.org/D142213

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[WebAssembly][NFC] Reuse the regClassToValType helper in WebAssemblyMCInstLower

There's no need for WebAssemblyMCInstLower to carry its own functionally
equivalent implementation.

[WebAssembly][NFC] Refactor WasmSymbol type setting code

This refactors some code dealing with setting Wasm symbol types.
Some of the code dealing with types was moved from
`WebAssemblyUtilities` to

[WebAssembly][NFC] Refactor WasmSymbol type setting code

This refactors some code dealing with setting Wasm symbol types.
Some of the code dealing with types was moved from
`WebAssemblyUtilities` to `WebAssemblyTypeUtilities`.

Reviewed By: sbc100

Differential Revision: https://reviews.llvm.org/D118121

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[WebAssembly] Support clang -fwasm-exceptions for bitcode

This supports bitcode compilation using `clang -fwasm-exceptions`.

---

The current situation:

Currently the backend requires two options

[WebAssembly] Support clang -fwasm-exceptions for bitcode

This supports bitcode compilation using `clang -fwasm-exceptions`.

---

The current situation:

Currently the backend requires two options for Wasm EH:
`-wasm-enable-eh` and `-exception-model=wasm`. Wasm SjLj requires two
options as well: `-wasm-enable-sjlj` and `-exception-model=wasm`. When
using Wasm EH via Emscripten, you only need to pass `-fwasm-exceptions`,
and these options will be added within the clang driver. This
description will focus on the case of Wasm EH going forward, but Wasm
SjLj's case is similar.

When you pass `-fwasm-exceptions` to emcc and clang driver, the clang
driver adds these options to the command line that calls the clang
frontend (`clang -cc1`): `-mllvm -wasm-enable-eh` and
`-exception-model=wasm`. `-wasm-enable-eh` is prefixed with `-mllvm`, so
it is passed as is to the backend. But `-exception-model` is parsed and
processed within the clang frontend and stored in `LangOptions` class.
This info is later transferred to `TargetOptions` class, and then
eventually passed to `MCAsmInfo` class. All LLVM code queries this
`MCAsmInfo` to get the exception model.

---

Problem:

The problem is the whole `LangOptions` processing is bypassed when
compiling bitcode, so the information transfer of `LangOptions` ->
`TargetOptions` -> `MCAsmInfo` does not happen. They are all set to
`ExceptionHandling::None`, which is the default value.

---

What other targets do, and why we can't do the same:

Other targets support bitcode compilation by the clang driver, but they
can do that by using different triples. For example, X86 target supports
multiple triples, each of which has its own subclass of `MCAsmInfo`, so
it can hardcode the appropriate exception model within those subclasses'
constructors. But we don't have separate triples for each exception
mode: none, emscripten, and wasm.

---

What this CL does:

If we can figure out whether `-wasm-enable-eh` is passed to the backend,
we can programatically set the exception model from the backend, rather
than requiring it to be passed.

So we check `WasmEnableEH` and `WasmEnableSjLj` variables, which are
`cl::opt` for `-wasm-enable-eh` and `-wasm-enable-sjlj`, in
`WebAssemblyMCAsmInfo` constructor, and if either of them is set, we set
`MCAsmInfo.ExceptionType` to Wasm. `TargetOptions` cannot be updated
there, so we make sure they are the same later.

Fixes https://github.com/emscripten-core/emscripten/issues/15712.

Reviewed By: dschuff

Differential Revision: https://reviews.llvm.org/D115893

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[WebAssembly] Lower global syms representing tables with .tabletype

This patch implements a fix to recognize global symbols that represent
WebAssembly appropriately and generate the necessary .table

[WebAssembly] Lower global syms representing tables with .tabletype

This patch implements a fix to recognize global symbols that represent
WebAssembly appropriately and generate the necessary .tabletype
directives.

Reviewed By: sbc100

Differential Revision: https://reviews.llvm.org/D115511

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[WebAssembly] Implementation of intrinsic for ref.null and HeapType removal

This patch implements the intrinsic for ref.null.
In the process of implementing int_wasm_ref_null_func() and
int_wasm_ref

[WebAssembly] Implementation of intrinsic for ref.null and HeapType removal

This patch implements the intrinsic for ref.null.
In the process of implementing int_wasm_ref_null_func() and
int_wasm_ref_null_extern() intrinsics, it removes the redundant
HeapType.

This also causes the textual assembler syntax for ref.null to
change. Instead of receiving an argument: `func` or `extern`, the
instruction mnemonic is either ref.null_func or ref.null_extern,
without the need for a further operand.

Reviewed By: tlively

Differential Revision: https://reviews.llvm.org/D114979

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[WebAssembly] Implementation of table.get/set for reftypes in LLVM IR

This change implements new DAG nodes TABLE_GET/TABLE_SET, and lowering
methods for load and stores of reference types from IR ar

[WebAssembly] Implementation of table.get/set for reftypes in LLVM IR

This change implements new DAG nodes TABLE_GET/TABLE_SET, and lowering
methods for load and stores of reference types from IR arrays. These
global LLVM IR arrays represent tables at the Wasm level.

Differential Revision: https://reviews.llvm.org/D111154

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[WebAssembly] Make EH work with dynamic linking

This makes Wasm EH work with dynamic linking. So far we were only able
to handle destructors, which do not use any tags or LSDA info.

1. This uses `T

[WebAssembly] Make EH work with dynamic linking

This makes Wasm EH work with dynamic linking. So far we were only able
to handle destructors, which do not use any tags or LSDA info.

1. This uses `TargetExternalSymbol` for `GCC_except_tableN` symbols,
which points to the address of per-function LSDA info. It is more
convenient to use than `MCSymbol` because it can take additional
target flags.

2. When lowering `wasm_lsda` intrinsic, if PIC is enabled, make the
symbol relative to `__memory_base` and generate the `add` node. If
PIC is disabled, continue to use the absolute address.

3. Make tag symbols (`__cpp_exception` and `__c_longjmp`) undefined in
the backend, because it is hard to make it work with dynamic
linking's loading order. Instead, we make all tag symbols undefined
in the LLVM backend and import it from JS.

4. Add support for undefined tags to the linker.

Companion patches:
- https://github.com/WebAssembly/binaryen/pull/4223
- https://github.com/emscripten-core/emscripten/pull/15266

Reviewed By: sbc100

Differential Revision: https://reviews.llvm.org/D111388

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[WebAssembly] Allow import and export of TLS symbols between DSOs

We previously had a limitation that TLS variables could not
be exported (and therefore could also not be imported). This
change rem

[WebAssembly] Allow import and export of TLS symbols between DSOs

We previously had a limitation that TLS variables could not
be exported (and therefore could also not be imported). This
change removed that limitation.

Differential Revision: https://reviews.llvm.org/D108877

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[WebAssembly] Tidy up EH/SjLj options

This CL is small, but the description can be a little long because I'm
trying to sum up the status quo for Emscripten/Wasm EH/SjLj options.

First, this CL adds

[WebAssembly] Tidy up EH/SjLj options

This CL is small, but the description can be a little long because I'm
trying to sum up the status quo for Emscripten/Wasm EH/SjLj options.

First, this CL adds an option for Wasm SjLj (`-wasm-enable-sjlj`), which
handles SjLj using Wasm EH. The implementation for this will be added as
a followup CL, but this adds the option first to do error checking.

This also adds an option for Wasm EH (`-wasm-enable-eh`), which has been
already implemented. Before we used `-exception-model=wasm` as the same
meaning as enabling Wasm EH, but after we add Wasm SjLj, it will be
possible to use Wasm EH instructions for Wasm SjLj while not enabling
EH, so going forward, to use Wasm EH, `opt` and `llc` will need this
option. This only affects `opt` and `llc` command lines and does not
affect Emscripten user interface.

Now we have two modes of EH (Emscripten/Wasm) and also two modes of SjLj
(also Emscripten/Wasm). The options corresponding to each of are:
- Emscripten EH: `-enable-emscripten-cxx-exceptions`
- Emscripten SjLj: `-enable-emscripten-sjlj`
- Wasm EH: `-wasm-enable-eh -exception-model=wasm`
`-mattr=+exception-handling`
- Wasm SjLj: `-wasm-enable-sjlj -exception-model=wasm`
`-mattr=+exception-handling`
The reason Wasm EH/SjLj's options are a little complicated are
`-exception-model` and `-mattr` are common LLVM options ane not under
our control. (`-mattr` can be omitted if it is embedded within the
bitcode file.)

And we have the following rules of the option composition:
- Emscripten EH and Wasm EH cannot be turned on at the same itme
- Emscripten SjLj and Wasm SjLj cannot be turned on at the same time
- Wasm SjLj should be used with Wasm EH

Which means we now allow these combinations:
- Emscripten EH + Emscripten SjLj: the current default in `emcc`
- Wasm EH + Emscripten SjLj:
This is allowed, but only as an interim step in which we are testing
Wasm EH but not yet have a working implementation of Wasm SjLj. This
will error out (D107687) in compile time if `setjmp` is called in a
function in which Wasm exception is used.
- Wasm EH + Wasm SjLj:
This will be the default mode later when using Wasm EH. Currently Wasm
SjLj implementation doesn't exist, so it doesn't work.
- Emscripten EH + Wasm SjLj will not work.

This CL moves these error checking routines to
`WebAssemblyPassConfig::addIRPasses`. Not sure if this is an ideal place
to do this, but I couldn't find elsewhere. Currently some checking is
done within LowerEmscriptenEHSjLj, but these checks only run if
LowerEmscriptenEHSjLj runs so it may not run when Wasm EH is used. This
moves that to `addIRPasses` and adds some more checks.

Currently LowerEmscriptenEHSjLj pass is responsible for Emscripten EH
and Emscripten SjLj. Wasm EH transformations are done in multiple
places, including WasmEHPrepare, LateEHPrepare, and CFGStackify. But in
the followup CL, LowerEmscriptenEHSjLj pass will be also responsible for
a part of Wasm SjLj transformation, because WasmSjLj will also be using
several Emscripten library functions, and we will be sharing more than
half of the transformation to do that between Emscripten SjLj and Wasm
SjLj.

Currently we have `-enable-emscripten-cxx-exceptions` and
`-enable-emscripten-sjlj` but these only work for `llc`, because for
`llc` we feed these options to the pass but when we run the pass using
`opt` the pass will be created with no options and the default options
will be used, which turns both Emscripten EH and Emscripten SjLj on.

Now we have one more SjLj option to care for, LowerEmscriptenEHSjLj pass
needs a finer way to control these options. This CL removes those
default parameters and make LowerEmscriptenEHSjLj pass read directly
from command line options specified. So if we only run
`opt -wasm-lower-em-ehsjlj`, currently both Emscripten EH and Emscripten
SjLj will run, but with this CL, none will run unless we additionally
pass `-enable-emscripten-cxx-exceptions` or `-enable-emscripten-sjlj`,
or both. This does not affect users; this only affects our `opt` tests
because `emcc` will not call either `opt` or `llc`. As a result of this,
our existing Emscripten EH/SjLj tests gained one or both of those
options in their `RUN` lines.

Reviewed By: dschuff

Differential Revision: https://reviews.llvm.org/D107685

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[WebAssembly] Misc. cosmetic changes in EH (NFC)

- Rename `wasm.catch` intrinsic to `wasm.catch.exn`, because we are
planning to add a separate `wasm.catch.longjmp` intrinsic which
returns two v

[WebAssembly] Misc. cosmetic changes in EH (NFC)

- Rename `wasm.catch` intrinsic to `wasm.catch.exn`, because we are
planning to add a separate `wasm.catch.longjmp` intrinsic which
returns two values.
- Rename several variables
- Remove an unnecessary parameter from `canLongjmp` and `isEmAsmCall`
from LowerEmscriptenEHSjLj pass
- Add `-verify-machineinstrs` in a test for a safety measure
- Add more comments + fix some errors in comments
- Replace `std::vector` with `SmallVector` for cases likely with small
number of elements
- Renamed `EnableEH`/`EnableSjLj` to `EnableEmEH`/`EnableEmSjLj`: We are
soon going to add `EnableWasmSjLj`, so this makes the distincion
clearer

Reviewed By: tlively

Differential Revision: https://reviews.llvm.org/D107405

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[WebAssembly] Implementation of global.get/set for reftypes in LLVM IR

Reland of 31859f896.

This change implements new DAG notes GLOBAL_GET/GLOBAL_SET, and
lowering methods for load and stores of r

[WebAssembly] Implementation of global.get/set for reftypes in LLVM IR

Reland of 31859f896.

This change implements new DAG notes GLOBAL_GET/GLOBAL_SET, and
lowering methods for load and stores of reference types from IR
globals. Once the lowering creates the new nodes, tablegen pattern
matches those and converts them to Wasm global.get/set.

Reviewed By: tlively

Differential Revision: https://reviews.llvm.org/D104797

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[WebAssembly] Added initial type checker to MC Assembler

This to protect against non-sensical instruction sequences being assembled,
which would either cause asserts/crashes further down, or a Wasm

[WebAssembly] Added initial type checker to MC Assembler

This to protect against non-sensical instruction sequences being assembled,
which would either cause asserts/crashes further down, or a Wasm module being output that doesn't validate.

Unlike a validator, this type checker is able to give type-errors as part of the parsing process, which makes the assembler much friendlier to be used by humans writing manual input.

Because the MC system is single pass (instructions aren't even stored in MC format, they are directly output) the type checker has to be single pass as well, which means that from now on .globaltype and .functype decls must come before their use. An extra pass is added to Codegen to collect information for this purpose, since AsmPrinter is normally single pass / streaming as well, and would otherwise generate this information on the fly.

A `-no-type-check` flag was added to llvm-mc (and any other tools that take asm input) that surpresses type errors, as a quick escape hatch for tests that were not intended to be type correct.

This is a first version of the type checker that ignores control flow, i.e. it checks that types are correct along the linear path, but not the branch path. This will still catch most errors. Branch checking could be added in the future.

Differential Revision: https://reviews.llvm.org/D104945

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Revert "[WebAssembly] Implementation of global.get/set for reftypes in LLVM IR"

This reverts commit 4facbf213c51e4add2e8c19b08d5e58ad71c72de.

```
********************
FAIL: LLVM :: CodeGen/WebAssem

Revert "[WebAssembly] Implementation of global.get/set for reftypes in LLVM IR"

This reverts commit 4facbf213c51e4add2e8c19b08d5e58ad71c72de.

```
********************
FAIL: LLVM :: CodeGen/WebAssembly/funcref-call.ll (44466 of 44468)
******************** TEST 'LLVM :: CodeGen/WebAssembly/funcref-call.ll' FAILED ********************
Script:
--
: 'RUN: at line 1'; /builddirs/llvm-project/build-Clang12/bin/llc < /repositories/llvm-project/llvm/test/CodeGen/WebAssembly/funcref-call.ll --mtriple=wasm32-unknown-unknown -asm-verbose=false -mattr=+reference-types | /builddirs/llvm-project/build-Clang12/bin/FileCheck /repositories/llvm-project/llvm/test/CodeGen/WebAssembly/funcref-call.ll
--
Exit Code: 2

Command Output (stderr):
--
llc: /repositories/llvm-project/llvm/include/llvm/Support/LowLevelTypeImpl.h:44: static llvm::LLT llvm::LLT::scalar(unsigned int): Assertion `SizeInBits > 0 && "invalid scalar size"' failed.

```

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[WebAssembly] Implementation of global.get/set for reftypes in LLVM IR

Reland of 31859f896.

This change implements new DAG notes GLOBAL_GET/GLOBAL_SET, and
lowering methods for load and stores of r

[WebAssembly] Implementation of global.get/set for reftypes in LLVM IR

Reland of 31859f896.

This change implements new DAG notes GLOBAL_GET/GLOBAL_SET, and
lowering methods for load and stores of reference types from IR
globals. Once the lowering creates the new nodes, tablegen pattern
matches those and converts them to Wasm global.get/set.

Differential Revision: https://reviews.llvm.org/D104797

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[WebAssembly] Rename event to tag

We recently decided to change 'event' to 'tag', and 'event section' to
'tag section', out of the rationale that the section contains a
generalized tag that referenc

[WebAssembly] Rename event to tag

We recently decided to change 'event' to 'tag', and 'event section' to
'tag section', out of the rationale that the section contains a
generalized tag that references a type, which may be used for something
other than exceptions, and the name 'event' can be confusing in the web
context.

See
- https://github.com/WebAssembly/exception-handling/issues/159#issuecomment-857910130
- https://github.com/WebAssembly/exception-handling/pull/161

Reviewed By: tlively

Differential Revision: https://reviews.llvm.org/D104423

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Revert "Implementation of global.get/set for reftypes in LLVM IR"

This reverts commit 31859f896cf90d64904134ce7b31230f374c3fcc.

Causing SVE and RISCV-V test failures on bots.

Implementation of global.get/set for reftypes in LLVM IR

This change implements new DAG notes GLOBAL_GET/GLOBAL_SET, and
lowering methods for load and stores of reference types from IR
globals. Once

Implementation of global.get/set for reftypes in LLVM IR

This change implements new DAG notes GLOBAL_GET/GLOBAL_SET, and
lowering methods for load and stores of reference types from IR
globals. Once the lowering creates the new nodes, tablegen pattern
matches those and converts them to Wasm global.get/set.

Reviewed By: tlively

Differential Revision: https://reviews.llvm.org/D95425

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[WebAssembly] Fix PIC/GOT codegen for wasm64

__table_base is know 64-bit, since in LLVM it represents a function pointer offset
__table_base32 is a copy in wasm32 for use in elem init expr, since no

[WebAssembly] Fix PIC/GOT codegen for wasm64

__table_base is know 64-bit, since in LLVM it represents a function pointer offset
__table_base32 is a copy in wasm32 for use in elem init expr, since no truncation may be used there.
New reloc R_WASM_TABLE_INDEX_REL_SLEB64 added

Differential Revision: https://reviews.llvm.org/D101784

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