Commit Graph

861 Commits

Author SHA1 Message Date
Thomas Lively cbabfc63b1 [WebAssembly] Custom combines for f32x4.demote_zero_f64x2
Replace the clang builtin function and LLVM intrinsic for
f32x4.demote_zero_f64x2 with combines from normal SDNodes. Also add missing
combines for i32x4.trunc_sat_zero_f64x2_{s,u}, which share the same pattern.

Differential Revision: https://reviews.llvm.org/D105755
2021-07-12 10:32:18 -07:00
Thomas Lively e5220104d0 [WebAssembly] Custom combines for f64x2.promote_low_f32x4
Replace the clang builtin function and LLVM intrinsic previously used to select
the f64x2.promote_low_f32x4 instruction with custom combines from standard
SelectionDAG nodes. Implement the new combines to share code with the similar
combines for f64x2.convert_low_i32x4_{s,u}. Resolves PR50232.

Differential Revision: https://reviews.llvm.org/D105675
2021-07-09 18:59:29 -07:00
Derek Schuff ac02baab48 WebAssembly: Update datalayout to match fp128 ABI change
This fix goes along with d1a96e906c
and makes the fp128 alignment match clang's long double alignment.

Differential Revision: https://reviews.llvm.org/D105749
2021-07-09 16:51:36 -07:00
Wouter van Oortmerssen 9647a6f719 [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
2021-07-09 14:07:25 -07:00
Thomas Lively 3dd75f5371 [WebAssembly] Scalarize extract_vector_elt of binops
Override the `shouldScalarizeBinop` target lowering hook using the same
implementation used in the x86 backend. This causes `extract_vector_elt`s of
vector binary ops to be scalarized if the scalarized version would be supported.

Differential Revision: https://reviews.llvm.org/D105646
2021-07-08 14:31:53 -07:00
Thomas Lively f8c5a4c670 [WebAssembly] Optimize out shift masks
WebAssembly's shift instructions implicitly masks the shift count, so optimize
out redundant explicit masks of the shift count. For vector shifts, this
currently only works if the mask is applied before splatting the shift count,
but this should be addressed in a future commit. Resolves PR49655.

Differential Revision: https://reviews.llvm.org/D105600
2021-07-07 23:14:31 -07:00
Roman Lebedev c2c0d3ea89
Revert "[WebAssembly] Implementation of global.get/set for reftypes in LLVM IR"
This reverts commit 4facbf213c.

```
********************
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.

```
2021-07-02 11:49:51 +03:00
Paulo Matos 4facbf213c [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
2021-07-02 09:46:28 +02:00
Nikita Popov f8aaec19e6 [OpaquePtr] Support forward references in textual IR
Currently, LLParser will create a Function/GlobalVariable forward
reference based on the desired pointer type and then modify it when
it is declared. With opaque pointers, we generally do not know the
correct type to use until we see the declaration.

Solve this by creating the forward reference with a dummy type, and
then performing a RAUW with the correct Function/GlobalVariable when
it is declared. The approach is adopted from
b5b55963f6.

This results in a change to the use list order, which is why we see
test changes on some module passes that are not stable under use list
reordering.

Differential Revision: https://reviews.llvm.org/D104950
2021-06-29 20:10:31 +02:00
Heejin Ahn 1d891d44f3 [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
2021-06-17 20:34:19 -07:00
Bjorn Pettersson 4c7f820b2b Update @llvm.powi to handle different int sizes for the exponent
This can be seen as a follow up to commit 0ee439b705,
that changed the second argument of __powidf2, __powisf2 and
__powitf2 in compiler-rt from si_int to int. That was to align with
how those runtimes are defined in libgcc.
One thing that seem to have been missing in that patch was to make
sure that the rest of LLVM also handle that the argument now depends
on the size of int (not using the si_int machine mode for 32-bit).
When using __builtin_powi for a target with 16-bit int clang crashed.
And when emitting libcalls to those rtlib functions, typically when
lowering @llvm.powi), the backend would always prepare the exponent
argument as an i32 which caused miscompiles when the rtlib was
compiled with 16-bit int.

The solution used here is to use an overloaded type for the second
argument in @llvm.powi. This way clang can use the "correct" type
when lowering __builtin_powi, and then later when emitting the libcall
it is assumed that the type used in @llvm.powi matches the rtlib
function.

One thing that needed some extra attention was that when vectorizing
calls several passes did not support that several arguments could
be overloaded in the intrinsics. This patch allows overload of a
scalar operand by adding hasVectorInstrinsicOverloadedScalarOpd, with
an entry for powi.

Differential Revision: https://reviews.llvm.org/D99439
2021-06-17 09:38:28 +02:00
David Spickett 64de8763aa Revert "Implementation of global.get/set for reftypes in LLVM IR"
This reverts commit 31859f896c.

Causing SVE and RISCV-V test failures on bots.
2021-06-10 10:11:17 +00:00
Paulo Matos 31859f896c 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
2021-06-10 10:07:45 +02:00
Andy Wingo 82f92e35c6 [WebAssembly][CodeGen] IR support for WebAssembly local variables
This patch adds TargetStackID::WasmLocal.  This stack holds locations of
values that are only addressable by name -- not via a pointer to memory.
For the WebAssembly target, these objects are lowered to WebAssembly
local variables, which are managed by the WebAssembly run-time and are
not addressable by linear memory.

For the WebAssembly target IR indicates that an AllocaInst should be put
on TargetStackID::WasmLocal by putting it in the non-integral address
space WASM_ADDRESS_SPACE_WASM_VAR, with value 1.  SROA will mostly lift
these allocations to SSA locals, but any alloca that reaches instruction
selection (usually in non-optimized builds) will be assigned the new
TargetStackID there.  Loads and stores to those values are transformed
to new WebAssemblyISD::LOCAL_GET / WebAssemblyISD::LOCAL_SET nodes,
which then lower to the type-specific LOCAL_GET_I32 etc instructions via
tablegen patterns.

Differential Revision: https://reviews.llvm.org/D101140
2021-06-01 11:31:39 +02:00
Andy Wingo bc1ad6e3c4 Revert "[WebAssembly][CodeGen] IR support for WebAssembly local variables"
This reverts commit bf35f4af51.  There was
an error in a shared-library build.
2021-05-31 10:55:15 +02:00
Andy Wingo bf35f4af51 [WebAssembly][CodeGen] IR support for WebAssembly local variables
This patch adds TargetStackID::WasmLocal.  This stack holds locations of
values that are only addressable by name -- not via a pointer to memory.
For the WebAssembly target, these objects are lowered to WebAssembly
local variables, which are managed by the WebAssembly run-time and are
not addressable by linear memory.

For the WebAssembly target IR indicates that an AllocaInst should be put
on TargetStackID::WasmLocal by putting it in the non-integral address
space WASM_ADDRESS_SPACE_WASM_VAR, with value 1.  SROA will mostly lift
these allocations to SSA locals, but any alloca that reaches instruction
selection (usually in non-optimized builds) will be assigned the new
TargetStackID there.  Loads and stores to those values are transformed
to new WebAssemblyISD::LOCAL_GET / WebAssemblyISD::LOCAL_SET nodes,
which then lower to the type-specific LOCAL_GET_I32 etc instructions via
tablegen patterns.

Differential Revision: https://reviews.llvm.org/D101140
2021-05-31 10:40:38 +02:00
Andy Wingo ca5f07f8c4 Revert "[WebAssembly][CodeGen] IR support for WebAssembly local variables"
This reverts commit 00ecf18979, as it
broke the AMDGPU build.  Will reland later with a fix.
2021-05-28 12:42:12 +02:00
Andy Wingo 00ecf18979 [WebAssembly][CodeGen] IR support for WebAssembly local variables
This patch adds TargetStackID::WasmLocal.  This stack holds locations of
values that are only addressable by name -- not via a pointer to memory.
For the WebAssembly target, these objects are lowered to WebAssembly
local variables, which are managed by the WebAssembly run-time and are
not addressable by linear memory.

For the WebAssembly target IR indicates that an AllocaInst should be put
on TargetStackID::WasmLocal by putting it in the non-integral address
space WASM_ADDRESS_SPACE_WASM_VAR, with value 1.  SROA will mostly lift
these allocations to SSA locals, but any alloca that reaches instruction
selection (usually in non-optimized builds) will be assigned the new
TargetStackID there.  Loads and stores to those values are transformed
to new WebAssemblyISD::LOCAL_GET / WebAssemblyISD::LOCAL_SET nodes,
which then lower to the type-specific LOCAL_GET_I32 etc instructions via
tablegen patterns.

Differential Revision: https://reviews.llvm.org/D101140
2021-05-28 11:07:41 +02:00
Heejin Ahn a64ebb8637 [WebAssembly] Add NullifyDebugValueLists pass
`WebAssemblyDebugValueManager` does not currently handle
`DBG_VALUE_LIST`, which is a recent addition to LLVM. We tried to
nullify them within the constructor of `WebAssemblyDebugValueManager` in
D102589, but it made the class error-prone to use because it deletes
instructions within the constructor and thus invalidates existing
iterators within the BB, so the user of the class should take special
care not to use invalidated iterators. This actually caused a bug in
ExplicitLocals pass.

Instead of trying to fix ExplicitLocals pass to make the iterator usage
correct, which is possible but error-prone, this adds
NullifyDebugValueLists pass that nullifies all `DBG_VALUE_LIST`
instructions before we run WebAssembly specific passes in the backend.
We can remove this pass after we implement handlers for
`DBG_VALUE_LIST`s in `WebAssemblyDebugValueManager` and elsewhere.

Fixes https://github.com/emscripten-core/emscripten/issues/14255.

Reviewed By: dschuff

Differential Revision: https://reviews.llvm.org/D102999
2021-05-24 11:36:01 -07:00
serge-sans-paille 4ab3041acb Revert "[NFC] remove explicit default value for strboolattr attribute in tests"
This reverts commit bda6e5bee0.

See https://lab.llvm.org/buildbot/#/builders/109/builds/15424 for instance
2021-05-24 19:43:40 +02:00
serge-sans-paille bda6e5bee0 [NFC] remove explicit default value for strboolattr attribute in tests
Since d6de1e1a71, no attributes is quivalent to
setting attribute to false.

This is a preliminary commit for https://reviews.llvm.org/D99080
2021-05-24 19:31:04 +02:00
Heejin Ahn 412a3381f7 [WebAssembly] Ignore filters in Emscripten EH landingpads
We have been handling filters and landingpads incorrectly all along. We
pass clauses' (catches') types to `__cxa_find_matching_catch` in JS glue
code, which returns the thrown pointer and sets the selector using
`setTempRet0()`.

We apparently have been doing the same for filters' (exception specs')
types; we pass them to `__cxa_find_matching_catch` just the same way as
clauses. And `__cxa_find_matching_catch` treats all given types as
clauses. So it is a little surprising; maybe we intended to do something
from the JS side and didn't end up doing?

So anyway, I don't think supporting exception specs in Emscripten EH is
a priority, but this can actually cause incorrect results for normal
catches when functions are inlined and the inlined spec type has a
parent-child relationship with the catch's type.

---

The below is an example of a bug that can happen when inlining and class
hierarchy is mixed. If you are busy you can skip this part:
```
struct A {};
struct B : A {};

void bar() throw (B) { throw B(); }

void foo() {
  try {
    bar();
  } catch (A &) {
    fputs ("Expected result\n", stdout);
  }
}
```

In the unoptimized code, `bar`'s landingpad will have a filter for `B`
and `foo`'s landingpad will have a clause for `A`. But when `bar` is
inlined into `foo`, `foo`'s landingpad has both a filter for `B` and a
clause for `A`, and it passes the both types to
`__cxa_find_matching_catch`:
```
__cxa_find_matching_catch(typeinfo for B, typeinfo for A)
```
`__cxa_find_matching_catch` thinks both are clauses, and looks at the
first type `B`, which belongs to a filter. And the thrown type is `B`,
so it thinks the first type `B` is caught. But this makes it return an
incorrect selector, because it is supposed to catch the exception using
the second type `A`, which is a parent of `B`. As a result, the `foo` in
the example program above does not print "Expected result" but just
throws the exception to the caller. (This wouldn't have happened if `A`
and `B` are completely disjoint types, such as `float` and `int`)

Fixes https://bugs.llvm.org/show_bug.cgi?id=50357.

Reviewed By: dschuff, kripken

Differential Revision: https://reviews.llvm.org/D102795
2021-05-20 01:28:16 -07:00
Heejin Ahn 6e1c1dac4c [WebAssembly] Nullify DBG_VALUE_LISTs in DebugValueManager
WebAssemblyDebugValueManager class currently does not handle
DBG_VALUE_LIST instructions correctly for two reasons, which are
explained in https://bugs.llvm.org/show_bug.cgi?id=50361.

This effectively nullifies DBG_VALUE_LISTs in
WebAssemblyDebugValueManager so that the info will appear as "optimized
out" in debuggers but still be at least correct in the meantime.

Reviewed By: dschuff, jmorse

Differential Revision: https://reviews.llvm.org/D102589
2021-05-17 13:47:36 -07:00
Heejin Ahn 71fbfb499a [WebAssembly] Omit DBG_VALUE after terminator
When a stackified variable has an associated `DBG_VALUE` instruction,
DebugFixup pass adds a `DBG_VALUE` instruction after the stackified
value's last use to clear the variable's debug range info. But when the
last use instruction is a terminator, it can cause a verification
failure (when run with `-verify-machineinstrs`) because there are no
instructions allowed after a terminator.

For example:
```
%myvar = ...
DBG_VALUE target-index(wasm-operand-stack), $noreg, !"myvar", ...
BR_IF 0, %myvar, ...
DBG_VALUE $noreg, $noreg, !"myvar", ...
```
In this test, `%myvar` is stackified, so the first `DBG_VALUE`
instruction's first operand has changed to `wasm-operand-stack` to
denote it. And an additional `DBG_VALUE` instruction is added after its
last use, `BR_IF`, to signal variable `myvar` is not in the operand
stack anymore. But because the `DBG_VALUE` instruction is added after
the `BR_IF`, a terminator, it fails MachineVerifier.

`DBG_VALUE` instructions are used in `DbgEntityHistoryCalculator` to
compute value ranges to emit DWARF info, and it turns out the
`DbgEntityHistoryCalculator` terminates ranges at the end of a BB, so we
don't need to emit `DBG_VALUE` after a terminator.

Fixes https://bugs.llvm.org/show_bug.cgi?id=50175.

Reviewed By: dschuff

Differential Revision: https://reviews.llvm.org/D102309
2021-05-14 03:48:19 -07:00
Heejin Ahn 8e35a18e4a [WebAssembly] Support Emscripten EH/SjLj in Wasm64
In wasm64, the signatures of some library functions and global variables
defined in Emscripten change:
- `emscripten_longjmp`: `(i32, i32) -> ()` -> `(i64, i32) -> ()`
  This changes because the first argument is the address of a memory
  buffer. This in turn causes more changes below.
- `setThrew`: `(i32, i32) -> ()` -> `(i64, i32) -> ()`
  `emscripten_longjmp` calls `setThrew` with the i64 buffer argument as
  the first parameter.
- `__THREW__` (global var): `i32` to `i64`
  `setThrew`'s first argument is set to this `__THREW__` variable, so it
  should change to i64 as well.
- `testSetjmp`: `(i32, i32*, i32) -> (i32)` -> `(i64, i32*, i32) -> (i32)`
  In the code transformation done in this pass, the value of `__THREW__`
  is passed as the first parameter of `testSetjmp`.

This patch creates some helper functions to easily get types that become
different depending on the wasm32/wasm64, and uses them to change
various function signatures and code transformations. Also updates the
tests with WASM32/WASM64 check lines.

(Untested) Emscripten side patch: https://github.com/emscripten-core/emscripten/pull/14108

Reviewed By: aardappel

Differential Revision: https://reviews.llvm.org/D101985
2021-05-14 03:45:09 -07:00
Sam Clegg 3041b16f73 [WebAssembly] Add TLS data segment flag: WASM_SEG_FLAG_TLS
Previously the linker was relying solely on the name of the segment
to imply TLS.

Differential Revision: https://reviews.llvm.org/D102202
2021-05-12 13:31:02 -07:00
Heejin Ahn ba38b72ec2 [WebAssembly] Allow Wasm EH with Emscripten SjLj
We explicitly made it error out in D101403, out of a good intention that
the error message will make people less confusing. Turns out, we weren't
failing all cases of wasm EH + SjLj; only a few cases were failing and
our client was able to get around by fixing source code, but now we made
it fail for all cases, even the cases that previously succeeded fail,
which we didn't intend. This reverts that change.

Reviewed By: tlively

Differential Revision: https://reviews.llvm.org/D102364
2021-05-12 13:27:04 -07:00
Andy Wingo b2f21b145a [CodeGen][WebAssembly] Better lowering for WASM_SYMBOL_TYPE_GLOBAL symbols
As we have been missing support for WebAssembly globals on the IR level,
the lowering of WASM_SYMBOL_TYPE_GLOBAL to IR was incomplete.  This
commit fleshes out the lowering support, lowering references to and
definitions of addrspace(1) values to correctly typed
WASM_SYMBOL_TYPE_GLOBAL symbols.

Depends on D101608.

Differential Revision: https://reviews.llvm.org/D101913
2021-05-11 11:47:40 +02:00
Paulo Matos d7086af214 [WebAssembly] Support for WebAssembly globals in LLVM IR
This patch adds support for WebAssembly globals in LLVM IR, representing
them as pointers to global values, in a non-default, non-integral
address space.  Instruction selection legalizes loads and stores to
these pointers to new WebAssemblyISD nodes GLOBAL_GET and GLOBAL_SET.
Once the lowering creates the new nodes, tablegen pattern matches those
and converts them to Wasm global.get/set of the appropriate type.

Based on work by Paulo Matos in https://reviews.llvm.org/D95425.

Reviewed By: pmatos

Differential Revision: https://reviews.llvm.org/D101608
2021-05-11 11:19:29 +02:00
Thomas Lively 89333b35a7 [WebAssembly] Set alignment to 1 for SIMD memory intrinsics
The WebAssembly SIMD intrinsics in wasm_simd128.h generally try not to require
any particular alignment for memory operations to be maximally flexible. For
builtin memory access functions and their corresponding LLVM IR intrinsics,
there's no way to set the expected alignment, so the best we can do is set the
alignment to 1 in the backend. This change means that the alignment hints in the
emitted code will no longer be incorrect when users use the intrinsics to access
unaligned data.

Differential Revision: https://reviews.llvm.org/D101850
2021-05-05 11:59:33 -07:00
Thomas Lively 14ca2e5e22 [WebAssembly] Mark abs of v2i64 as legal
We previously had an ISel pattern for i64x2.abs, but because the ISDNode was not
marked legal for v2i64, the instruction was not being selected.

Differential Revision: https://reviews.llvm.org/D101803
2021-05-04 13:25:32 -07:00
Heejin Ahn b4a5dd4da9 [WebAssembly] Error when wasm EH is used with Emscripten EH/SjLj
- Error out when both Emscripten EH and wasm EH are used together, i.e.,
  both `-enable-emscripten-cxx-exceptions` and `-exception-model=wasm`
  are given together. This will not happen if you use Emscripten, but
  this can happen when you call `llc` manually with wrong set of
  arguments.
- Currently we don't yet support using wasm EH with Emscripten SjLj.
  Unlike `-enable-emscripten-cxx-exceptions` which is turned on only
  when you use `emcc -s DISABLE_EXCEPTION_CATCHING=0`,
  `-enable-emscripten-sjlj` is turned on by Emscripten by default. So we
  error out only when it is turned on and `setjmp` or `longjmp` is
  actually used.

Reviewed By: tlively

Differential Revision: https://reviews.llvm.org/D101403
2021-04-27 16:07:53 -07:00
Heejin Ahn c390621aeb [WebAssembly] Fix fixEndsAtEndOfFunction for delegate
Background:
CFGStackify's [[ 398f253400/llvm/lib/Target/WebAssembly/WebAssemblyCFGStackify.cpp (L1481-L1540) | fixEndsAtEndOfFunction ]] fixes block/loop/try's return
type when the end of function is unreachable and the function return
type is not void. So if a function returns i32 and `block`-`end` wraps the
whole function, i.e., the `block`'s `end` is the last instruction of the
function, the `block`'s return type should be i32 too:
```
block i32
  ...
end
end_function
```

If there are consecutive `end`s, this signature has to be propagate to
those blocks too, like:
```
block i32
  ...
  block i32
    ...
  end
end
end_function
```

This applies to `try`-`end` too:
```
try i32
  ...
catch
  ...
end
end_function
```

In case of `try`, we not only follow consecutive `end`s but also follow
`catch`, because for the type of the whole `try` to be i32, both `try`
and `catch` parts have to be i32:
```
try i32
  ...
  block i32
    ...
  end
catch
  ...
  block i32
    ...
  end
end
end_function
```

---

Previously we only handled consecutive `end`s or `end` before a `catch`.
But now we have `delegate`, which serves like `end` for
`try`-`delegate`. So we have to follow `delegate` too and mark its
corresponding `try` as i32 (the function's return type):
```
try i32
  ...
catch
  ...
  try i32    ;; Here
    ...
  delegate N
end
end_function
```

Reviewed By: tlively

Differential Revision: https://reviews.llvm.org/D101036
2021-04-22 15:32:00 -07:00
Heejin Ahn b3e88ccba7 [WebAssembly] Serialize params/results in MachineFunctionInfo
This adds support for YAML serialization of `Params` and `Results`
fields in `WebAssemblyMachineFunctionInfo`. Types are printed as `MVT`'s
string representation. This is for writing MIR tests easier.

The tests added are testing simple parsing and printing of `params` /
`results` fields under `machineFunctionInfo`.

Reviewed By: tlively

Differential Revision: https://reviews.llvm.org/D101029
2021-04-22 15:31:09 -07:00
Thomas Lively 693d767c60 [WebAssembly] More codegen for f64x2.convert_low_i32x4_{s,u}
af7925b4dd added a custom DAG combine for recognizing fp-to-ints of
extract_subvectors that could be lowered to f64x2.convert_low_i32x4_{s,u}
instructions. This commit extends the combines to recognize equivalent
extract_subvectors of fp-to-ints as well.

Differential Revision: https://reviews.llvm.org/D100790
2021-04-20 12:37:13 -07:00
Thomas Lively e657c84fa1 [WebAssembly] Use v128.const instead of splats for constants
We previously used splats instead of v128.const to materialize vector constants
because V8 did not support v128.const. Now that V8 supports v128.const, we can
use v128.const instead. Although this increases code size, it should also
increase performance (or at least require fewer engine-side optimizations), so
it is an appropriate change to make.

Differential Revision: https://reviews.llvm.org/D100716
2021-04-19 12:43:59 -07:00
Thomas Lively 5c729750a6 [WebAssembly] Remove saturating fp-to-int target intrinsics
Use the target-independent @llvm.fptosi and @llvm.fptoui intrinsics instead.
This includes removing the instrinsics for i32x4.trunc_sat_zero_f64x2_{s,u},
which are now represented in IR as a saturating truncation to a v2i32 followed by
a concatenation with a zero vector.

Differential Revision: https://reviews.llvm.org/D100596
2021-04-16 12:11:20 -07:00
Thomas Lively 6a18cc23ef [WebAssembly] Codegen for i64x2.extend_{low,high}_i32x4_{s,u}
Removes the builtins and intrinsics used to opt in to using these instructions
and replaces them with normal ISel patterns now that they are no longer
prototypes.

Differential Revision: https://reviews.llvm.org/D100402
2021-04-14 13:43:09 -07:00
Thomas Lively af7925b4dd [WebAssembly] Codegen for f64x2.convert_low_i32x4_{s,u}
Add a custom DAG combine and ISD opcode for detecting patterns like

  (uint_to_fp (extract_subvector ...))

before the extract_subvector is expanded to ensure that they will ultimately
lower to f64x2.convert_low_i32x4_{s,u} instructions. Since these instructions
are no longer prototypes and can now be produced via standard IR, this commit
also removes the target intrinsics and builtins that had been used to prototype
the instructions.

Differential Revision: https://reviews.llvm.org/D100425
2021-04-14 10:42:45 -07:00
Thomas Lively af7ab81ce3 [WebAssembly] Use standard intrinsics for f32x4 and f64x2 ops
Now that these instructions are no longer prototypes, we do not need to be
careful about keeping them opt-in and can use the standard LLVM infrastructure
for them. This commit removes the bespoke intrinsics we were using to represent
these operations in favor of the corresponding target-independent intrinsics.
The clang builtins are preserved because there is no standard way to easily
represent these operations in C/C++.

For consistency with the scalar codegen in the Wasm backend, the intrinsic used
to represent {f32x4,f64x2}.nearest is @llvm.nearbyint even though
@llvm.roundeven better captures the semantics of the underlying Wasm
instruction. Replacing our use of @llvm.nearbyint with use of @llvm.roundeven is
left to a potential future patch.

Differential Revision: https://reviews.llvm.org/D100411
2021-04-14 09:19:27 -07:00
Thomas Lively ea8dd3ee2e [WebAssembly] Update v128.any_true
In the final SIMD spec, there is only a single v128.any_true instruction, rather
than one for each lane interpretation because the semantics do not depend on the
lane interpretation.

Differential Revision: https://reviews.llvm.org/D100241
2021-04-11 11:13:16 -07:00
Thomas Lively f30c429da6 [WebAssembly] Add shuffles as an option for lowering BUILD_VECTOR
When lowering a BUILD_VECTOR SDNode, we choose among various possible vector
creation instructions in an attempt to minimize the total number of instructions
used. We previously considered using swizzles, consts, and splats, and this
patch adds shuffles as well. A common pattern that now lowers to shuffles is
when two 64-bit vectors are concatenated. Previously, concatenations generally
lowered to sequences of extract_lane and replace_lane instructions when they
could have been a single shuffle.

Differential Revision: https://reviews.llvm.org/D100018
2021-04-09 11:21:49 -07:00
Wouter van Oortmerssen 04e9cd09c8 [WebAssembly] Fix for PIC external symbol ISEL
wasm64 was missing DAG ISEL patterns for external symbol based global.get, but simply adding these analogous to the existing 32-bit versions doesn't work.
This is because we are conflating the 32-bit global index with the pointer represented by the external symbol, which for wasm32 happened to work.
The simplest fix is to pretend we have a 64-bit global index. This sounds incorrect, but is immaterial since once this index is stored as a MachineOperand it becomes 64-bit anyway (and has been all along). As such, the EmitInstrWithCustomInserter based implementation I experimented with become a no-op and no further changes in the C++ code are required.

Differential Revision: https://reviews.llvm.org/D99904
2021-04-08 12:07:38 -07:00
Sam Parker f1313b3b24 [NFC][WebAssembly] Removed mangled name from test. 2021-04-06 08:55:27 +01:00
Sam Parker 92e7771483 [WebAssembly] Invert branch condition on xor input
A frequent pattern for floating point conditional branches use an xor
to invert the input for the branch. Instead we can fold away the xor
by swapping the branch target instead.

Differential Revision: https://reviews.llvm.org/D99171
2021-04-01 09:23:28 +01:00
Thomas Lively 45783d0e8a [WebAssembly] Implement i64x2 comparisons
Removes the prototype builtin and intrinsic for i64x2.eq and implements that
instruction as well as the other i64x2 comparison instructions in the final SIMD
spec. Unsigned comparisons were not included in the final spec, so they still
need to be scalarized via a custom lowering.

Differential Revision: https://reviews.llvm.org/D99623
2021-03-31 10:46:17 -07:00
Andy Wingo 9ac5620cb8 [WebAssembly] Rename WasmLimits::Initial to ::Minimum. NFC.
This patch renames the "Initial" member of WasmLimits to the name used
in the spec, "Minimum".

In the core WebAssembly specification, the Limits data type has one
required "min" member and one optional "max" member, indicating the
minimum required size of the corresponding table or memory, and the
maximum size, if any.

Although the WebAssembly spec does instantiate locally-defined tables
and memories with the initial size being equal to the minimum size, it
can't impose such a requirement for imports.  It doesn't make sense to
require an initial size for a memory import, for example.  The compiler
can only sensibly express the minimum and maximum sizes.

See
https://github.com/WebAssembly/js-types/blob/master/proposals/js-types/Overview.md#naming-of-size-limits
for a related discussion that agrees that the right name of "initial" is
"minimum" when querying the type of a table or memory from JavaScript.
(Of course it still makes sense for JS to speak in terms of an initial
size when it explicitly instantiates memories and tables.)

Differential Revision: https://reviews.llvm.org/D99186
2021-03-24 09:10:11 +01:00
Thomas Lively f5764a8654 [WebAssembly] Finalize SIMD names and opcodes
Updates the names (e.g. widen => extend, saturate => sat) and opcodes of all
SIMD instructions to match the finalized SIMD spec. Deliberately does not change
the public interface in wasm_simd128.h yet; that will require more care.

Depends on D98466.

Differential Revision: https://reviews.llvm.org/D98676
2021-03-18 11:21:25 -07:00
Thomas Lively 2f2ae08da9 [WebAssembly] Remove experimental SIMD instructions
Removes the instruction definitions, intrinsics, and builtins for qfma/qfms,
signselect, and prefetch instructions, which were not included in the final
WebAssembly SIMD spec.

Depends on D98457.

Differential Revision: https://reviews.llvm.org/D98466
2021-03-18 11:21:24 -07:00
Thomas Lively 8638c897f4 [WebAssembly] Remove unimplemented-simd target feature
Now that the WebAssembly SIMD specification is finalized and engines are
generally up-to-date, there is no need for a separate target feature for gating
SIMD instructions that engines have not implemented. With this change,
v128.const is now enabled by default with the simd128 target feature.

Differential Revision: https://reviews.llvm.org/D98457
2021-03-18 10:23:12 -07:00