Commit Graph

662 Commits

Author SHA1 Message Date
Thomas Lively 918e90559b [WebAssembly] Make stack pointer args inhibit tail calls
Summary:
Also make return calls terminator instructions so epilogues are
inserted before them rather than after them. Together, these changes
make WebAssembly's tail call optimization more stack-safe.

Reviewers: aheejin, dschuff

Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D73943
2020-02-13 16:43:53 -08:00
Thomas Lively e252293d06 [WebAssembly] Add cbrt function signatures
Summary:
Fixes a crash in the backend where optimizations produce calls to the
cbrt runtime functions. Fixes PR 44227.

Reviewers: aheejin

Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D74259
2020-02-13 13:18:42 -08:00
Yuanfang Chen 4ad7685258 Revert "Revert "Reland "[Support] make report_fatal_error `abort` instead of `exit`"""
This reverts commit 80a34ae311 with fixes.

Previously, since bots turning on EXPENSIVE_CHECKS are essentially turning on
MachineVerifierPass by default on X86 and the fact that
inline-asm-avx-v-constraint-32bit.ll and inline-asm-avx512vl-v-constraint-32bit.ll
are not expected to generate functioning machine code, this would go
down to `report_fatal_error` in MachineVerifierPass. Here passing
`-verify-machineinstrs=0` to make the intent explicit.
2020-02-13 10:16:06 -08:00
Yuanfang Chen 17122ec10a Revert "Revert "Revert "Reland "[Support] make report_fatal_error `abort` instead of `exit`""""
This reverts commit bb51d24330.
2020-02-13 10:08:05 -08:00
Yuanfang Chen bb51d24330 Revert "Revert "Reland "[Support] make report_fatal_error `abort` instead of `exit`"""
This reverts commit 80a34ae311 with fixes.

On bots llvm-clang-x86_64-expensive-checks-ubuntu and
llvm-clang-x86_64-expensive-checks-debian only,
llc returns 0 for these two tests unexpectedly. I tweaked the RUN line a little
bit in the hope that LIT is the culprit since this change is not in the
codepath these tests are testing.
llvm\test\CodeGen\X86\inline-asm-avx-v-constraint-32bit.ll
llvm\test\CodeGen\X86\inline-asm-avx512vl-v-constraint-32bit.ll
2020-02-13 10:02:53 -08:00
Yuanfang Chen 80a34ae311 Revert "Reland "[Support] make report_fatal_error `abort` instead of `exit`""
This reverts commit rGcd5b308b828e, rGcd5b308b828e, rG8cedf0e2994c.

There are issues to be investigated for polly bots and bots turning on
EXPENSIVE_CHECKS.
2020-02-11 20:41:53 -08:00
Yuanfang Chen 8cedf0e299 Reland "[Support] make report_fatal_error `abort` instead of `exit`"
Summary:
Reland D67847 after D73742 is committed. Replace `sys::Process::Exit(1)`
with `abort` in `report_fatal_error`.

After this patch, for tools turning on `CrashRecoveryContext`,
crash handler installed by `CrashRecoveryContext` is called unless
they installed a non-returning handler using `llvm::install_fatal_error_handler`
like `cc1_main` currently does.

Reviewers: rnk, MaskRay, aganea, hans, espindola, jhenderson

Subscribers: jholewinski, qcolombet, dschuff, jyknight, emaste, sdardis, nemanjai, jvesely, nhaehnle, sbc100, jgravelle-google, hiraditya, aheejin, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, sabuasal, niosHD, jrtc27, zzheng, edward-jones, atanasyan, steven_wu, rogfer01, MartinMosbeck, brucehoult, the_o, dexonsmith, PkmX, rupprecht, jocewei, jsji, Jim, dmgreen, lenary, s.egerton, pzheng, sameer.abuasal, apazos, luismarques, kerbowa, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D74456
2020-02-11 18:20:40 -08:00
Sam Clegg caeb6cfbc2 [WebAssembly] Fix signature of __powitf2 libcall
Add tests for @llvm.powi.f64/f128.

See: https://llvm.org/docs/LangRef.html#llvm-powi-intrinsic

Differential Revision: https://reviews.llvm.org/D74274
2020-02-07 20:30:47 -08:00
Heejin Ahn 5b5cbfe135 [WebAssembly] Add debug info to insts in Emscripten SjLj
Summary:
This makes sure all newly create instructions in Emscripten SjLj has
appropriate debug info attached. Fixes
https://github.com/emscripten-core/emscripten/issues/9797.

Reviewers: kripken

Subscribers: dschuff, aprantl, sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D74269
2020-02-07 19:08:39 -08:00
Jinsong Ji 01edae1271 [AsmPrinter] Print FP constant in hexadecimal form instead
Printing floating point number in decimal is inconvenient for humans.
Verbose asm output will print out floating point values in comments, it
helps.

But in lots of cases, users still need additional work to covert the
decimal back to hex or binary to check the bit patterns,
especially when there are small precision difference.

Hexadecimal form is one of the supported form in LLVM IR, and easier for
debugging.

This patch try to print all FP constant in hex form instead.

Reviewed By: RKSimon

Differential Revision: https://reviews.llvm.org/D73566
2020-02-07 16:00:55 +00:00
Thomas Lively 649aba93a2 Revert "[WebAssembly][InstrEmitter] Foundation for multivalue call lowering"
Summary:
This reverts commit 3ef169e586. The
purpose of this commit was to allow stack machines to perform
instruction selection for instructions with variadic defs. However,
MachineInstrs fundamentally cannot support variadic defs right now, so
this change does not turn out to be useful.

Depends on D73927.

Reviewers: aheejin

Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D73928
2020-02-04 20:04:59 -08:00
Thomas Lively 27748363da [WebAssembly] Enable recently implemented SIMD operations
Summary:
Moves a batch of instructions from unimplemented-simd128 to simd128
because they have recently become available in V8.

Reviewers: aheejin

Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D73926
2020-02-04 18:36:32 -08:00
Derek Schuff d966bf830f [WebAssembly] Preserve debug frame base information through register coloring
2 fixes:

Register coloring can re-assign virtual registers. When the frame base register
is colored, update the DwarfFrameBase accordingly When the frame base register
is stackified, do not attempt to encode DW_AT_frame_base as a local In the
future we will presumably want to handle this case better but for now we can
emit worse debug info rather than crashing.

Differential Revision: https://reviews.llvm.org/D73581
2020-01-28 16:58:15 -08:00
Heejin Ahn 65eb11306e [WebAssembly] Update bleeding-edge CPU features
Summary:
This adds bulk memory and tail call to "bleeding-edge" CPU, since their
implementation in LLVM/clang seems mostly complete.

Reviewers: tlively

Subscribers: dschuff, sbc100, jgravelle-google, sunfish, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D73322
2020-01-24 14:27:35 -08:00
Heejin Ahn 764f4089e8 [WebAssembly] Add reference types target feature
Summary:
This adds the reference types target feature. This does not enable any
more functionality in LLVM/clang for now, but this is necessary to embed
the info in the target features section, which is used by Binaryen and
Emscripten. It turned out that after D69832 `-fwasm-exceptions` crashed
because we didn't have the reference types target feature.

Reviewers: tlively

Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D73320
2020-01-24 14:26:27 -08:00
Heejin Ahn 580d7838dd [WebAssembly] Fix resume-only case in Emscripten EH
Summary:
D72308 incorrectly assumed `resume` cannot exist without a `landingpad`,
which is not true. This sets `Changed` to true whenever we make changes
to a function, including creating a call to `__resumeException` within a
function without a landing pad.

Reviewers: tlively

Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D73308
2020-01-23 18:13:52 -08:00
Thomas Lively 3ef169e586 [WebAssembly][InstrEmitter] Foundation for multivalue call lowering
Summary:
WebAssembly is unique among upstream targets in that it does not at
any point use physical registers to store values. Instead, it uses
virtual registers to model positions in its value stack. This means
that some target-independent lowering activities that would use
physical registers need to use virtual registers instead for
WebAssembly and similar downstream targets. This CL generalizes the
existing `usesPhysRegsForPEI` lowering hook to
`usesPhysRegsForValues` in preparation for using it in more places.

One such place is in InstrEmitter for instructions that have variadic
defs. On register machines, it only makes sense for these defs to be
physical registers, but for WebAssembly they must be virtual registers
like any other values. This CL changes InstrEmitter to check the new
target lowering hook to determine whether variadic defs should be
physical or virtual registers.

These changes are necessary to support a generalized CALL instruction
for WebAssembly that is capable of returning an arbitrary number of
arguments. Fully implementing that instruction will require additional
changes that are described in comments here but left for a follow up
commit.

Reviewers: aheejin, dschuff, qcolombet

Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D71484
2020-01-21 11:13:46 -08:00
Derek Schuff ff171acf84 [WebAssembly] Track frame registers through VReg and local allocation
This change has 2 components:

Target-independent: add a method getDwarfFrameBase to TargetFrameLowering. It
describes how the Dwarf frame base will be encoded.  That can be a register (the
default), the CFA (which replaces NVPTX-specific logic in DwarfCompileUnit), or
a DW_OP_WASM_location descriptr.

WebAssembly: Allow WebAssemblyFunctionInfo::getFrameRegister to return the
correct virtual register instead of FP32/SP32 after WebAssemblyReplacePhysRegs
has run.  Make WebAssemblyExplicitLocals store the local it allocates for the
frame register. Use this local information to implement getDwarfFrameBase

The result is that the DW_AT_frame_base attribute is correctly encoded for each
subprogram, and each param and local variable has a correct DW_AT_location that
uses DW_OP_fbreg to refer to the frame base.

This is a reland of rG3a05c3969c18 with fixes for the expensive-checks
and Windows builds

Differential Revision: https://reviews.llvm.org/D71681
2020-01-17 17:23:56 -08:00
Derek Schuff 80906d9d16 Revert "[WebAssembly] Track frame registers through VReg and local allocation"
This reverts commit 3a05c3969c.
It breaks under expensive-checks and on Windows
2020-01-16 14:38:00 -08:00
Derek Schuff 3a05c3969c [WebAssembly] Track frame registers through VReg and local allocation
This change has 2 components:

Target-independent: add a method getDwarfFrameBase to TargetFrameLowering. It
describes how the Dwarf frame base will be encoded.  That can be a register (the
default), the CFA (which replaces NVPTX-specific logic in DwarfCompileUnit), or
a DW_OP_WASM_location descriptr.

WebAssembly: Allow WebAssemblyFunctionInfo::getFrameRegister to return the
correct virtual register instead of FP32/SP32 after WebAssemblyReplacePhysRegs
has run.  Make WebAssemblyExplicitLocals store the local it allocates for the
frame register. Use this local information to implement getDwarfFrameBase

The result is that the DW_AT_frame_base attribute is correctly encoded for each
subprogram, and each param and local variable has a correct DW_AT_location that
uses DW_OP_fbreg to refer to the frame base.

Differential Revision: https://reviews.llvm.org/D71681
2020-01-16 13:51:17 -08:00
Yuanfang Chen 6e24c6037f Revert "[Support] make report_fatal_error `abort` instead of `exit`"
This reverts commit 647c3f4e47.

Got bots failure from sanitizer-windows and maybe others.
2020-01-15 17:52:25 -08:00
Yuanfang Chen 647c3f4e47 [Support] make report_fatal_error `abort` instead of `exit`
Summary:
This patch could be treated as a rebase of D33960. It also fixes PR35547.
A fix for `llvm/test/Other/close-stderr.ll` is proposed in D68164. Seems
the consensus is that the test is passing by chance and I'm not
sure how important it is for us. So it is removed like in D33960 for now.
The rest of the test fixes are just adding `--crash` flag to `not` tool.

** The reason it fixes PR35547 is

`exit` does cleanup including calling class destructor whereas `abort`
does not do any cleanup. In multithreading environment such as ThinLTO or JIT,
threads may share states which mostly are ManagedStatic<>. If faulting thread
tearing down a class when another thread is using it, there are chances of
memory corruption. This is bad 1. It will stop error reporting like pretty
stack printer; 2. The memory corruption is distracting and nondeterministic in
terms of error message, and corruption type (depending one the timing, it
could be double free, heap free after use, etc.).

Reviewers: rnk, chandlerc, zturner, sepavloff, MaskRay, espindola

Reviewed By: rnk, MaskRay

Subscribers: wuzish, jholewinski, qcolombet, dschuff, jyknight, emaste, sdardis, nemanjai, jvesely, nhaehnle, sbc100, arichardson, jgravelle-google, aheejin, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, PkmX, jocewei, jsji, lenary, s.egerton, pzheng, cfe-commits, MaskRay, filcab, davide, MatzeB, mehdi_amini, hiraditya, steven_wu, dexonsmith, rupprecht, seiya, llvm-commits

Tags: #llvm, #clang

Differential Revision: https://reviews.llvm.org/D67847
2020-01-15 17:05:13 -08:00
Matt Arsenault 67ec8744d7 llc: Change behavior of -mattr with existing attribute
Append this to the existing target-features attribute on the function.

Some flags ignore existing attributes, and some overwrite them. Move
towards consistently respecting existing attributes if present. Since
target features act as a state machine on their own, append to the
function attribute. The backend default added feature list, function
attributes, and -mattr will all be appended together, and the later
features can individually toggle the earlier settings.
2020-01-15 19:46:01 -05:00
Heejin Ahn 21f7b36209 [WebAssembly] Fix landingpad-only case in Emscripten EH
Summary:
Previously we didn't set `Changed` to true when there are only landing
pads but not invokes. This fixes it and we set `Changed` to true
whenever we have landing pads. (There can't be invokes without landing
pads, so that case is covered too)

The test case for this has to be a separate file because this pass is a
`ModulePass` and `Changed` is computed based on the whole module.

Reviewers: tlively

Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D72308
2020-01-06 17:02:32 -08:00
Simon Pilgrim eb0e1978df [TargetLowering] SimplifyDemandedBits - call SimplifyMultipleUseDemandedBits for ISD::EXTRACT_VECTOR_ELT (REAPPLIED)
This patch attempts to peek through vectors based on the demanded bits/elt of a particular ISD::EXTRACT_VECTOR_ELT node, allowing us to avoid dependencies on ops that have no impact on the extract.

In particular this helps remove some unnecessary scalar->vector->scalar patterns.

The wasm shift patterns are annoying - @tlively has indicated that the wasm vector shift codegen are to be refactored in the near-term and isn't considered a major issue.

Reapplied after reversion at rL368660 due to PR42982 which was fixed at rGca7fdd41bda0.

Differential Revision: https://reviews.llvm.org/D65887
2020-01-04 13:15:50 +00:00
Fangrui Song a36ddf0aa9 Migrate function attribute "no-frame-pointer-elim"="false" to "frame-pointer"="none" as cleanups after D56351 2019-12-24 16:27:51 -08:00
Thomas Lively 71eb8023d8 [WebAssembly] Add avgr_u intrinsics and require nuw in patterns
Summary:
The vector pattern `(a + b + 1) / 2` was previously selected to an
avgr_u instruction regardless of nuw flags, but this is incorrect in
the case where either addition may have an unsigned wrap. This CL
changes the existing pattern to require both adds to have nuw flags
and adds builtin functions and intrinsics for the avgr_u instructions
because the corrected pattern is not representable in C.

Reviewers: aheejin

Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D71648
2019-12-18 15:31:38 -08:00
Thomas Lively f1b351e14a [WebAssembly] Implement SIMD {i8x16,i16x8}.avgr_u instructions
Summary:
These instructions were added to the spec proposal in
https://github.com/WebAssembly/simd/pull/126. Their semantics are
equivalent to `(a + b + 1) / 2`. The opcode for the experimental
i32x4.dot_i16x8_s is also bumped due to a collision with the
i8x16.avgr_u opcode.

Reviewers: aheejin

Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D71628
2019-12-17 15:05:50 -08:00
Thomas Lively 3a93756dfb [WebAssembly] Replace SIMD int min/max builtins with patterns
Summary:
The instructions were originally implemented via builtins and
intrinsics so users would have to explicitly opt-in to using
them. This was useful while were validating whether these instructions
should have been merged into the spec proposal. Now that they have
been, we can use normal codegen patterns, so the intrinsics and
builtins are no longer useful.

Reviewers: aheejin

Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D71500
2019-12-16 11:48:49 -08:00
Fangrui Song fdb408f348 [MC] Delete unused MCAsmInfoELF::UsesNonexecutableStackSection after EM_WEBASSEMBLY was removed in D48744
This removes remnant of D15969 which hasn't been removed by D48744.
2019-12-15 15:43:30 -08:00
Sam Clegg 881d877846 [WebAssembly] Add new `export_name` clang attribute for controlling wasm export names
This is equivalent to the existing `import_name` and `import_module`
attributes which control the import names in the final wasm binary
produced by lld.

This maps the existing

This attribute currently requires a string rather than using the
symbol name for a couple of reasons:

1. Avoid confusion with static and dynamic linking which is
   based on symbol name.  Exporting a function from a wasm module using
   this directive is orthogonal to both static and dynamic linking.
2. Avoids name mangling.

Differential Revision: https://reviews.llvm.org/D70520
2019-12-11 11:54:57 -08:00
Thomas Lively 194d7ec081 [WebAssembly] Fix miscompile of select with and
Summary:
Rolls back the remaining bad optimizations introduced in
eb15d00193. Some of them were already rolled back in e661f946a7 and
this finishes the job.

Fixes https://bugs.llvm.org/show_bug.cgi?id=44012.

Reviewers: dschuff, aheejin

Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70347
2019-11-15 16:22:01 -08:00
Thomas Lively 935c84c3c2 [WebAssembly] Add experimental SIMD dot product instruction
Summary:
This instruction is not merged to the spec proposal, but we need it to
be implemented in the toolchain to experiment with it. It is available
only on an opt-in basis through a clang builtin.

Defined in https://github.com/WebAssembly/simd/pull/127.

Depends on D69696.

Reviewers: aheejin

Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D69697
2019-11-01 10:45:48 -07:00
Thomas Lively ecb7daf68f Reland "[WebAssembly] Expand setcc of v2i64"
This reverts commit e5cae5692b, which
reverted 11850a6305. The original revert
was done because of breakage that was actually in a separate commit,
2ab1b8c1ec, which was also reverted and
has since been fixed and relanded.
2019-11-01 10:34:01 -07:00
Thomas Lively a07019a275 [WebAssembly] SIMD integer min and max instructions
Summary:
Introduces a clang builtins and LLVM intrinsics representing integer
min/max instructions. These instructions have not been merged to the
SIMD spec proposal yet, so they are currently opt-in only via builtins
and not produced by general pattern matching. If these instructions
are accepted into the spec proposal the builtins and intrinsics will
be replaced with normal pattern matching.

Defined in https://github.com/WebAssembly/simd/pull/27.

Reviewers: aheejin

Reviewed By: aheejin

Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D69696
2019-10-31 20:22:11 -07:00
Thomas Lively 3479fd25b9 Reland "[WebAssembly] Handle multiple loads of splatted loads"
This reverts commit 92a25fbf11 and fixes
the ambiguous method call that was causing build failures.
2019-10-31 20:02:24 -07:00
Vlad Tsyrklevich 92a25fbf11 Revert "[WebAssembly] Handle multiple loads of splatted loads"
This reverts commit 2ab1b8c1ec, it is
causing build failures on numerous bots, including
sanitizer-x86_64-linux-bootstrap-ubsan. My previous revert was for the
wrong commit.
2019-10-31 16:52:44 -07:00
Vlad Tsyrklevich e5cae5692b Revert "[WebAssembly] Expand setcc of v2i64"
This reverts commit 11850a6305, it was
causing build failures on numerous bots, including
sanitizer-x86_64-linux-bootstrap-ubsan.
2019-10-31 16:44:09 -07:00
Thomas Lively 2ab1b8c1ec [WebAssembly] Handle multiple loads of splatted loads
Summary:
Fixes an ISel failure when a splatted load is used more than once. The
failure was due to the hacks we were doing in ISel lowering to
preserve the original load as the operand of a LOAD_SPLAT node. The
fix is to properly lower the splatted use of the load to a separate
LOAD_SPLAT node.

Reviewers: aheejin

Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69640
2019-10-31 14:59:30 -07:00
Thomas Lively 11850a6305 [WebAssembly] Expand setcc of v2i64
Summary:
The SIMD spec does not include i64x2 comparisons, so they need to be
expanded. Using setOperationAction to expand them also causes f64x2
comparisons to be expanded, so setCondCodeAction needs to be used
instead. But since there are no legal condition codes, the legalizer
does not know how to expand the comparisons. We therefore manually
unroll the operation, taking care to fill each lane with -1 or 0
rather than 1 or 0 for consistency with the other vector comparisons.

Reviewers: aheejin

Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69604
2019-10-31 14:22:30 -07:00
Sanjay Patel 85a2146c15 [SDAG] fold insert_vector_elt with undef index
Similar to:
rG4c47617627fb

This makes the DAG behavior consistent with IR's insertelement.

https://bugs.llvm.org/show_bug.cgi?id=42689

I've tried to maintain test intent for AArch64 and WebAssembly
by replacing undef index operands with something else.
2019-10-27 15:28:43 -04:00
Sanjay Patel 4c47617627 [SDAG] fold extract_vector_elt with undef index
This makes the DAG behavior consistent with IR's extractelement after:
rGb32e4664a715

https://bugs.llvm.org/show_bug.cgi?id=42689

I've tried to maintain test intent for WebAssembly.
The AMDGPU test is trying to test for crashing or other bad behavior,
but I'm not sure if that's possible after this change.
2019-10-25 19:27:26 -04:00
Thomas Lively 393d0f799f [WebAssembly] Allow multivalue signatures in object files
Summary:
Also changes the wasm YAML format to reflect the possibility of having
multiple return types and to put the returns after the params for
consistency with the binary encoding.

Reviewers: aheejin, sbc100

Subscribers: dschuff, jgravelle-google, hiraditya, sunfish, arphaman, rupprecht, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69156

llvm-svn: 375283
2019-10-18 20:27:30 +00:00
Thomas Lively 2cb27072ce [WebAssembly] Allow multivalue types in block signature operands
Summary:
Renames `ExprType` to the more apt `BlockType` and adds a variant for
multivalue blocks. Currently non-void blocks are only generated at the
end of functions where the block return type needs to agree with the
function return type, and that remains true for multivalue
blocks. That invariant means that the actual signature does not need
to be stored in the block signature `MachineOperand` because it can be
inferred by `WebAssemblyMCInstLower` from the return type of the
parent function. `WebAssemblyMCInstLower` continues to lower block
signature operands to immediates when possible but lowers multivalue
signatures to function type symbols. The AsmParser and Disassembler
are updated to handle multivalue block types as well.

Reviewers: aheejin, dschuff, aardappel

Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68889

llvm-svn: 374933
2019-10-15 18:28:22 +00:00
Thomas Lively 232fd99d9e [WebAssembly] Trapping fptoint builtins and intrinsics
Summary:
The WebAssembly backend lowers fptoint instructions to a code sequence
that checks for overflow to avoid traps because fptoint is supposed to
be speculatable. These new builtins and intrinsics give users a way to
depend on the trapping semantics of the underlying instructions and
avoid the extra code generated normally.

Patch by coffee and tlively.

Reviewers: aheejin

Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D68902

llvm-svn: 374856
2019-10-15 01:11:51 +00:00
Thomas Lively 00f9e5aa76 [WebAssembly] Make returns variadic
Summary:
This is necessary and sufficient to get simple cases of multiple
return working with multivalue enabled. More complex cases will
require block and loop signatures to be generalized to potentially be
type indices as well.

Reviewers: aheejin, dschuff

Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68684

llvm-svn: 374235
2019-10-09 21:42:08 +00:00
Thomas Lively 3419e90dc1 [WebAssembly] Add builtin and intrinsic for v8x16.swizzle
Summary:
This clang builtin and corresponding LLVM intrinsic are necessary to
expose the exact semantics of the underlying WebAssembly instruction
to users. LLVM produces a poison value if the dynamic swizzle indices
are greater than the vector size, but the WebAssembly instruction sets
the corresponding output lane to zero. Users who depend on this
behavior can safely use this builtin.

Depends on D68527.

Reviewers: aheejin, dschuff

Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D68531

llvm-svn: 374189
2019-10-09 17:45:47 +00:00
Thomas Lively d5b7a4e2e8 [WebAssembly] v8x16.swizzle and rewrite BUILD_VECTOR lowering
Summary:
Adds the new v8x16.swizzle SIMD instruction as specified at
https://github.com/WebAssembly/simd/blob/master/proposals/simd/SIMD.md#swizzling-using-variable-indices.
In addition to adding swizzles as a candidate lowering in
LowerBUILD_VECTOR, also rewrites and simplifies the lowering to
minimize the number of replace_lanes necessary rather than trying to
minimize code size. This leads to more uses of v128.const instead of
splats, which is expected to increase performance.

The new code will be easier to tune once V8 implements all the vector
construction operations, and it will also be easier to add new
candidate instructions in the future if necessary.

Reviewers: aheejin, dschuff

Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68527

llvm-svn: 374188
2019-10-09 17:39:19 +00:00
Heejin Ahn 6a37c5d6fc [WebAssembly] Fix a bug in 'try' placement
Summary:
When searching for local expression tree created by stackified
registers, for 'block' placement, we start the search from the previous
instruction of a BB's terminator. But in 'try''s case, we should start
from the previous instruction of a call that can throw, or a EH_LABEL
that precedes the call, because the return values of the call's previous
instructions can be stackified and consumed by the throwing call.

For example,
```
  i32.call @foo
  call @bar         ; may throw
  br $label0
```
In this case, if we start the search from the previous instruction of
the terminator (`br` here), we end up stopping at `call @bar` and place
a 'try' between `i32.call @foo` and `call @bar`, because `call @bar`
does not have a return value so it is not a local expression tree of
`br`.

But in this case, unlike when placing 'block's, we should start the
search from `call @bar`, because the return value of `i32.call @foo` is
stackified and used by `call @bar`.

Reviewers: dschuff

Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68619

llvm-svn: 374073
2019-10-08 16:15:39 +00:00
Heejin Ahn a58ddba113 [WebAssembly] Add REQUIRES: asserts to cfg-stackify-eh.ll
This was missing in D68552.

llvm-svn: 374015
2019-10-08 02:50:27 +00:00