1453 Commits

Author SHA1 Message Date
Roman Lebedev
5bd901b404 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.

```
2021-07-02 11:49:51 +03:00
Paulo Matos
e346ccc104 [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
Martin Storsjö
9d14adb9f6 [llvm] Rename StringRef _lower() method calls to _insensitive()
This is a mechanical change. This actually also renames the
similarly named methods in the SmallString class, however these
methods don't seem to be used outside of the llvm subproject, so
this doesn't break building of the rest of the monorepo.
2021-06-25 00:22:01 +03:00
Heejin Ahn
f7b0205560 [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
David Spickett
17058150e4 Revert "Implementation of global.get/set for reftypes in LLVM IR"
This reverts commit 31859f896cf90d64904134ce7b31230f374c3fcc.

Causing SVE and RISCV-V test failures on bots.
2021-06-10 10:11:17 +00:00
Paulo Matos
fb9c8fd3dd 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
a2b88794ad [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
34f735fb88 Revert "[WebAssembly][CodeGen] IR support for WebAssembly local variables"
This reverts commit bf35f4af51cddd743435bb6b94a45592c967891a.  There was
an error in a shared-library build.
2021-05-31 10:55:15 +02:00
Andy Wingo
6faf61e8ac [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
89bbb9e629 Revert "[WebAssembly][CodeGen] IR support for WebAssembly local variables"
This reverts commit 00ecf18979e3326b3afee8af3dc701c53ffdc93f, as it
broke the AMDGPU build.  Will reland later with a fix.
2021-05-28 12:42:12 +02:00
Andy Wingo
6446c1dcda [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
3f66a78716 [WebAssembly] Add TargetInstrInfo::getCalleeOperand
DwarfDebug unconditionally assumes for all call instructions the 0th
operand is the callee operand, which seems to be true for other targets,
but not for WebAssembly. This adds `TargetInstrInfo::getCallOperand`
method whose default implementation returns `getOperand(0)` and makes
WebAssembly overrides it to use its own utility method to get the callee
operand.

This also fixes an existing bug in `WebAssembly::getCalleeOp`, which was
uncovered by this CL.

Reviewed By: dschuff, djtodoro

Differential Revision: https://reviews.llvm.org/D102978
2021-05-26 11:43:59 -07:00
Heejin Ahn
9c4b79c3d5 [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
Jessica Clarke
8c42ad8897 [SelectionDAG][Mips][PowerPC][RISCV][WebAssembly] Teach computeKnownBits/ComputeNumSignBits about atomics
Unlike normal loads these don't have an extension field, but we know
from TargetLowering whether these are sign-extending or zero-extending,
and so can optimise away unnecessary extensions.

This was noticed on RISC-V, where sign extensions in the calling
convention would result in unnecessary explicit extension instructions,
but this also fixes some Mips inefficiencies. PowerPC sees churn in the
tests as all the zero extensions are only for promoting 32-bit to
64-bit, but these zero extensions are still not optimised away as they
should be, likely due to i32 being a legal type.

This also simplifies the WebAssembly code somewhat, which currently
works around the lack of target-independent combines with some ugly
patterns that break once they're optimised away.

Re-landed with correct handling in ComputeNumSignBits for Tmp == VTBits,
where zero-extending atomics were incorrectly returning 0 rather than
the (slightly confusing) required return value of 1.

Re-landed again after D102819 fixed PowerPC to correctly zero-extend all
of its atomics as it claimed to do, since the combination of that bug
and this optimisation caused buildbot regressions.

Reviewed By: RKSimon, atanasyan

Differential Revision: https://reviews.llvm.org/D101342
2021-05-20 20:34:23 +01:00
Wouter van Oortmerssen
1184fb03b6 [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
2021-05-20 09:59:31 -07:00
Heejin Ahn
05d69ddc38 [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
6eb058e5ac [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
5ec2c45efb [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
871c0f68dd [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
Heejin Ahn
6ba804b88f [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
Stefan Pintilie
3947a17f41 Revert "[SelectionDAG][Mips][PowerPC][RISCV][WebAssembly] Teach computeKnownBits/ComputeNumSignBits about atomics"
This reverts commit 6c80361b8474535852afb2f7201370fb5f410091.
Breaks PowerPC Big Endian buildbots.
2021-05-12 09:46:18 -05:00
Andy Wingo
f0acbefefd [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
839dc2d28e [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
Sam Clegg
b94988cc08 Reland: "[lld][WebAssembly] Initial support merging string data"
This change was originally landed in: 5000a1b4b9edeb9e994f2a5b36da8d48599bea49
It was reverted in: 061e071d8c9b98526f35cad55a918a4f1615afd4

This change adds support for a new WASM_SEG_FLAG_STRINGS flag in
the object format which works in a similar fashion to SHF_STRINGS
in the ELF world.

Unlike the ELF linker this support is currently limited:
- No support for SHF_MERGE (non-string merging)
- Always do full tail merging ("lo" can be merged with "hello")
- Only support single byte strings (p2align 0)

Like the ELF linker merging is only performed at `-O1` and above.

This fixes part of https://bugs.llvm.org/show_bug.cgi?id=48828,
although crucially it doesn't not currently support debug sections
because they are not represented by data segments (they are custom
sections)

Differential Revision: https://reviews.llvm.org/D97657
2021-05-10 16:03:38 -07:00
Nico Weber
f766faca78 Revert "[lld][WebAssembly] Initial support merging string data"
This reverts commit 5000a1b4b9edeb9e994f2a5b36da8d48599bea49.
Breaks tests, see https://reviews.llvm.org/D97657#2749151

Easily repros locally with `ninja check-llvm-mc-webassembly`.
2021-05-10 18:28:28 -04:00
Sam Clegg
fcb19b5df4 [lld][WebAssembly] Initial support merging string data
This change adds support for a new WASM_SEG_FLAG_STRINGS flag in
the object format which works in a similar fashion to SHF_STRINGS
in the ELF world.

Unlike the ELF linker this support is currently limited:
- No support for SHF_MERGE (non-string merging)
- Always do full tail merging ("lo" can be merged with "hello")
- Only support single byte strings (p2align 0)

Like the ELF linker merging is only performed at `-O1` and above.

This fixes part of https://bugs.llvm.org/show_bug.cgi?id=48828,
although crucially it doesn't not currently support debug sections
because they are not represented by data segments (they are custom
sections)

Differential Revision: https://reviews.llvm.org/D97657
2021-05-10 13:15:12 -07:00
Jessica Clarke
cebf1171e8 [SelectionDAG][Mips][PowerPC][RISCV][WebAssembly] Teach computeKnownBits/ComputeNumSignBits about atomics
Unlike normal loads these don't have an extension field, but we know
from TargetLowering whether these are sign-extending or zero-extending,
and so can optimise away unnecessary extensions.

This was noticed on RISC-V, where sign extensions in the calling
convention would result in unnecessary explicit extension instructions,
but this also fixes some Mips inefficiencies. PowerPC sees churn in the
tests as all the zero extensions are only for promoting 32-bit to
64-bit, but these zero extensions are still not optimised away as they
should be, likely due to i32 being a legal type.

This also simplifies the WebAssembly code somewhat, which currently
works around the lack of target-independent combines with some ugly
patterns that break once they're optimised away.

Re-landed with correct handling in ComputeNumSignBits for Tmp == VTBits,
where zero-extending atomics were incorrectly returning 0 rather than
the (slightly confusing) required return value of 1.

Reviewed By: RKSimon, atanasyan

Differential Revision: https://reviews.llvm.org/D101342
2021-05-06 04:01:20 +01:00
Heejin Ahn
1c758eabb3 [WebAssembly] Fix JS code mentions in LowerEmscriptenEHSjLj
- Removes the mention of fastcomp, which is deprecated.
- Some functions in Emscripten have moved from JS glue code to
  compiler-rt/emscripten_setjmp.c and
  compiler-rt/emscripten_exception_builtins.c. This fixes comments about
  that.

Reviewed By: sbc100

Differential Revision: https://reviews.llvm.org/D101812
2021-05-05 17:04:14 -07:00
Thomas Lively
00da536b13 [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
Jessica Clarke
3018d0bd19 Revert "[SelectionDAG][Mips][PowerPC][RISCV][WebAssembly] Teach computeKnownBits/ComputeNumSignBits about atomics"
This seems to have broken sanitizers, giving lots of

  Assertion `NumBits <= MAX_INT_BITS && "bitwidth too large"' failed.

failures across multiple targets (currently X86 and PowerPC). Reverting
until I have a chance to reproduce and debug.

This reverts commit 6e876f9dedf00b24a96b8781e3b39d5282c43e91.
2021-05-05 17:02:05 +01:00
Jessica Clarke
d5dcd075dc [SelectionDAG][Mips][PowerPC][RISCV][WebAssembly] Teach computeKnownBits/ComputeNumSignBits about atomics
Unlike normal loads these don't have an extension field, but we know
from TargetLowering whether these are sign-extending or zero-extending,
and so can optimise away unnecessary extensions.

This was noticed on RISC-V, where sign extensions in the calling
convention would result in unnecessary explicit extension instructions,
but this also fixes some Mips inefficiencies. PowerPC sees churn in the
tests as all the zero extensions are only for promoting 32-bit to
64-bit, but these zero extensions are still not optimised away as they
should be, likely due to i32 being a legal type.

This also simplifies the WebAssembly code somewhat, which currently
works around the lack of target-independent combines with some ugly
patterns that break once they're optimised away.

Reviewed By: RKSimon, atanasyan

Differential Revision: https://reviews.llvm.org/D101342
2021-05-05 16:34:45 +01:00
Thomas Lively
4986a0d7fa [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
Paulo Matos
73ab51af76 [WebAssembly] Fixup order of ins variables for table instructions
WebAssembly instruction arguments should have their arguments ordered from
the deepest to the shallowest on the stack.
2021-05-03 13:04:51 -07:00
Heejin Ahn
0a60d3f451 [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
Craig Topper
50539da1c1 [SelectionDAG] Use a VTSDNode to store the saturation width for FP_TO_SINT_SAT/FP_TO_UINT_SAT
Previously we used an i32 constant to store the saturation width, but i32 isn't
legal on RISCV64. This wasn't a big deal to fix, but it is extra work for the
type legalizer.

This patch uses a VTSDNode to store the type similar to SEXT_INREG. This makes
it opaque to the type legalizer.

Reviewed By: nikic

Differential Revision: https://reviews.llvm.org/D101262
2021-04-27 14:38:42 -07:00
Heejin Ahn
5217fbac0b [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
4405bf5794 [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
Heejin Ahn
37702c2638 [WebAssembly] Put utility functions in Utils directory (NFC)
This CL
1. Creates Utils/ directory under lib/Target/WebAssembly
2. Moves existing WebAssemblyUtilities.cpp|h into the Utils/ directory
3. Creates Utils/WebAssemblyTypeUtilities.cpp|h and put type
   declarataions and type conversion functions scattered in various
   places into this single place.

It has been suggested several times that it is not easy to share utility
functions between subdirectories (AsmParser, DIsassembler, MCTargetDesc,
...). Sometimes we ended up [[ https://reviews.llvm.org/D92840#2478863 | duplicating ]] the same function because of
this.

There are already other targets doing this: AArch64, AMDGPU, and ARM
have Utils/ subdirectory under their target directory.

This extracts the utility functions into a single directory Utils/ and
make them sharable among all passes in WebAssembly/ and its
subdirectories. Also I believe gathering all type-related conversion
functionalities into a single place makes it more usable. (Actually I
was working on another CL that uses various type conversion functions
scattered in multiple places, which became the motivation for this CL.)

Reviewed By: dschuff, aardappel

Differential Revision: https://reviews.llvm.org/D100995
2021-04-22 15:29:43 -07:00
Sam Clegg
7d3fbb9953 [WebAssembly] Update README. NFC.
This is just a cleanup of the very high level stuff.  I'm sure there is
more to update here but I'll leave that to others and/or a followup.

Differential Revision: https://reviews.llvm.org/D100888
2021-04-20 16:59:08 -07:00
Sam Clegg
8c8f002458 [WebAssembly] Remove unused known_gcc_test_failures.txt. NFC
Differential Revision: https://reviews.llvm.org/D100887
2021-04-20 14:07:25 -07:00
Thomas Lively
1844c2454c [WebAssembly] More codegen for f64x2.convert_low_i32x4_{s,u}
af7925b4dd65 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
21a1775578 [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
135ccc6ee6 [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
e322e40bfa [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
63678cfe27 [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
Sander de Smalen
fed6e0656a [TTI] NFC: Change getArithmeticInstrCost to return InstructionCost
This patch migrates the TTI cost interfaces to return an InstructionCost.

See this patch for the introduction of the type: https://reviews.llvm.org/D91174
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2020-November/146408.html

Reviewed By: dmgreen

Differential Revision: https://reviews.llvm.org/D100317
2021-04-14 17:20:36 +01:00
Sander de Smalen
5aaf843fd4 [TTI] NFC: Change getVectorInstrCost to return InstructionCost
This patch migrates the TTI cost interfaces to return an InstructionCost.

See this patch for the introduction of the type: https://reviews.llvm.org/D91174
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2020-November/146408.html

Reviewed By: dmgreen

Differential Revision: https://reviews.llvm.org/D100315
2021-04-14 17:20:35 +01:00
Thomas Lively
4ba1e6bb91 [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
a397d1a74f [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
70a0c154ef [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