Summary:
Multivalue calls both take and return an arbitrary number of
arguments, but ISel only supports one or the other in a single
instruction. To get around this, calls are modeled as two pseudo
instructions during ISel. These pseudo instructions, CALL_PARAMS and
CALL_RESULTS, are recombined into a single CALL MachineInstr in a
custom emit hook.
RegStackification and the MC layer will additionally need to be made
aware of multivalue calls before the tests will produce correct
output.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D71496
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
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
This has two main effects:
- Optimizes debug info size by saving 221.86 MB of obj file size in a
Windows optimized+debug build of 'all'. This is 3.03% of 7,332.7MB of
object file size.
- Incremental step towards decoupling target intrinsics.
The enums are still compact, so adding and removing a single
target-specific intrinsic will trigger a rebuild of all of LLVM.
Assigning distinct target id spaces is potential future work.
Part of PR34259
Reviewers: efriedma, echristo, MaskRay
Reviewed By: echristo, MaskRay
Differential Revision: https://reviews.llvm.org/D71320
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.
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.
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
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
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
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
Summary:
Adds the new load_splat instructions as specified at
https://github.com/WebAssembly/simd/blob/master/proposals/simd/SIMD.md#load-and-splat.
DAGISel does not allow matching multiple copies of the same load in a
single pattern, so we use a new node in WebAssemblyISD to wrap loads
that should be splatted.
Depends on D67783.
Reviewers: aheejin
Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D67784
llvm-svn: 372655
Summary:
Large slowdowns were observed in Rust due to many small, constant
sized copies in conjunction with poorly-optimized memory.copy
implementations. Since memory.copy cannot be expected to be inlined
efficiently by engines at this time, stop using it for the smallest
copies. We continue to lower all memcpy intrinsics to memory.copy,
though.
Reviewers: aheejin, alexcrichton
Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, JDevlieghere, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D67639
llvm-svn: 372275
* Reordered MVT simple types to group scalable vector types
together.
* New range functions in MachineValueType.h to only iterate over
the fixed-length int/fp vector types.
* Stopped backends which don't support scalable vector types from
iterating over scalable types.
Reviewers: sdesmalen, greened
Reviewed By: greened
Differential Revision: https://reviews.llvm.org/D66339
llvm-svn: 372099
The patch introduces MakeLibCallOptions struct as suggested by @efriedma on D65497.
The struct contain argument flags which will pass to makeLibCall function.
The patch should not has any functionality changes.
Differential Revision: https://reviews.llvm.org/D65795
llvm-svn: 369622
Summary:
Fixes PR42973. Tests don't change because simd-arith.ll tests behavior
on unimplemented-simd128, which does not include any temporary
workarounds such as the one removed in this revision.
Reviewers: aheejin
Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish, dmgreen, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D66166
llvm-svn: 368868
Summary:
When the WebAssembly backend encounters a return type that doesn't
fit within i32, SelectionDAG performs sret demotion, adding an
additional argument to the start of the function that contains
a pointer to an sret buffer to use instead. However, this conflicts
with the emscripten sjlj lowering pass. There we translate calls like:
```
call {i32, i32} @foo()
```
into (in pseudo-llvm)
```
%addr = @foo
call {i32, i32} @__invoke_{i32,i32}(%addr)
```
i.e. we perform an indirect call through an extra function.
However, the sret transform now transforms this into
the equivalent of
```
%addr = @foo
%sret = alloca {i32, i32}
call {i32, i32} @__invoke_{i32,i32}(%sret, %addr)
```
(while simultaneously translation the implementation of @foo as well).
Unfortunately, this doesn't work out. The __invoke_ ABI expected
the function address to be the first argument, causing crashes.
There is several possible ways to fix this:
1. Implementing the sret rewrite at the IR level as well and performing
it as part of lowering to __invoke
2. Fixing the wasm backend to recognize that __invoke has a special ABI
3. A change to the binaryen/emscripten ABI to recognize this situation
This revision implements the middle option, teaching the backend to
treat __invoke_ functions specially in sret lowering. This is achieved
by
1) Introducing a new CallingConv ID for invoke functions
2) When this CallingConv ID is seen in the backend and the first argument
is marked as sret (a function pointer would never be marked as sret),
swapping the first two arguments.
Reviewed By: tlively, aheejin
Differential Revision: https://reviews.llvm.org/D65463
llvm-svn: 367935
Summary:
This is patch is part of a serie to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790
Reviewers: courbet, jfb, jakehehrlich
Reviewed By: jfb
Subscribers: wuzish, jholewinski, arsenm, dschuff, nemanjai, jvesely, nhaehnle, javed.absar, sbc100, jgravelle-google, hiraditya, aheejin, kbarton, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, rogfer01, MartinMosbeck, brucehoult, the_o, dexonsmith, PkmX, jocewei, jsji, s.egerton, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D65514
llvm-svn: 367828
Summary:
return_call and return_call_indirect are only valid if the return
types of the callee and caller match. We were previously not enforcing
that, which was producing invalid modules.
Reviewers: aheejin
Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D65246
llvm-svn: 367339
Summary:
Implements direct and indirect tail calls enabled by the 'tail-call'
feature in both DAG ISel and FastISel. Updates existing call tests and
adds new tests including a binary encoding test.
Reviewers: aheejin
Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D62877
llvm-svn: 364445
As discussed on D62910, we need to check whether particular types of memory access are allowed, not just their alignment/address-space.
This NFC patch adds a MachineMemOperand::Flags argument to allowsMemoryAccess and allowsMisalignedMemoryAccesses, and wires up calls to pass the relevant flags to them.
If people are happy with this approach I can then update X86TargetLowering::allowsMisalignedMemoryAccesses to handle misaligned NT load/stores.
Differential Revision: https://reviews.llvm.org/D63075
llvm-svn: 363179
Summary:
Adjusts the index and adds a bitcast around the vector operand of
EXTRACT_VECTOR_ELT so that its lane type matches the source type of
its parent sext_inreg. Without this bitcast the ISel patterns do not
match and ISel fails.
Reviewers: aheejin
Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D62646
llvm-svn: 362547
Summary:
In this patch, `ISD::RETURNADDR` is lowered on the emscripten target
to the new Emscripten runtime function `emscripten_return_address`, which
implements the functionality.
Patch by Guanzhong Chen
Reviewers: tlively, aheejin
Reviewed By: tlively
Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D62210
llvm-svn: 361454
We don't have FP exception limits in the IR constant folder for the binops (apart from strict ops),
so it does not make sense to have them here in the DAG either. Nothing else in the backend tries
to preserve exceptions (again outside of strict ops), so I don't see how this could have ever
worked for real code that cares about FP exceptions.
There are still cases (examples: unary opcodes in SDAG, FMA in IR) where we are trying (at least
partially) to preserve exceptions without even asking if the target supports FP exceptions. Those
should be corrected in subsequent patches.
Real support for FP exceptions requires several changes to handle the constrained/strict FP ops.
Differential Revision: https://reviews.llvm.org/D61331
llvm-svn: 359791
Add support for f16 libcalls in WebAssembly. This entails adding signatures
for the remaining F16 libcalls, and renaming gnu_f2h_ieee/gnu_h2f_ieee to
truncsfhf2/extendhfsf2 for consistency between f32 and f64/f128 (compiler-rt
already supports this).
Differential Revision: https://reviews.llvm.org/D61287
Reviewer: dschuff
llvm-svn: 359600
Summary:
Always convert switches to br_tables unless there is only one case,
which is equivalent to a simple branch. This reduces code size for wasm,
and we defer possible jump table optimizations to the VM.
Addresses PR41502.
Reviewers: kripken, sunfish
Subscribers: dschuff, sbc100, jgravelle-google, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D60966
llvm-svn: 359038
This change is in preparation for the addition of new target
operand flags for new relocation types. Have a symbol type as part
of the flag set makes it harder to use and AFAICT these are serving
no purpose.
Differential Revision: https://reviews.llvm.org/D60014
llvm-svn: 357548
This change implements lowering of references global symbols in PIC
mode.
This change implements lowering of global references in PIC mode using a
new @GOT reference type. @GOT references can be used with function or
data symbol names combined with the get_global instruction. In this case
the linker will insert the wasm global that stores the address of the
symbol (either in memory for data symbols or in the wasm table for
function symbols).
For now I'm continuing to use the R_WASM_GLOBAL_INDEX_LEB relocation
type for this type of reference which means that this relocation type
can refer to either a global or a function or data symbol. We could
choose to introduce specific relocation types for GOT entries in the
future. See the current dynamic linking proposal:
https://github.com/WebAssembly/tool-conventions/blob/master/DynamicLinking.md
Differential Revision: https://reviews.llvm.org/D54647
llvm-svn: 357022
The default implementation does we want and is going to more compatible
with dynamic linking (-fPIC) support that is planned.
This is NFC because currently we only build wasm with
`-relocation-model=static` which in turn means that the default
`isOffsetFoldingLegal` always returns true today.
Differential Revision: https://reviews.llvm.org/D54661
llvm-svn: 356410
Summary:
- Replaces some uses of `MachineFunction::iterator(MBB)` with
`MBB->getIterator()` and `MachineBasicBlock::iterator(MI)` with
`MI->getIterator()`, which are simpler.
- Replaces some uses of `std::prev` of `std::next` that takes a
MachineFunction or MachineBasicBlock iterator with `getPrevNode` and
`getNextNode`, which are also simpler.
Reviewers: sbc100
Subscribers: dschuff, sunfish, jgravelle-google, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D58913
llvm-svn: 355444
Summary:
This prevents crashes in instruction selection when these operations
are used. The tests check that the scalar version of the instruction
is used where applicable, although some expansions do not use the
scalar version.
Reviewers: aheejin
Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D58859
llvm-svn: 355261
For outgoing varargs arguments, it's necessary to check the OrigAlign field
of the corresponding OutputArg entry to determine argument alignment, rather
than just computing an alignment from the argument value type. This is
because types like fp128 are split into multiple argument values, with
narrower types that don't reflect the ABI alignment of the full fp128.
This fixes the printf("printfL: %4.*Lf\n", 2, lval); testcase.
Differential Revision: https://reviews.llvm.org/D58656
llvm-svn: 354846
Summary:
This patch fixes clang-tidy warnings on wasm-only files.
The list of checks used is:
`-*,clang-diagnostic-*,llvm-*,misc-*,-misc-unused-parameters,readability-identifier-naming,modernize-*`
(LLVM's default .clang-tidy list is the same except it does not have
`modernize-*`. But I've seen in multiple CLs in LLVM the modernize style
was recommended and code was fixed based on the style, so I added it as
well.)
The common fixes are:
- Variable names start with an uppercase letter
- Function names start with a lowercase letter
- Use `auto` when you use casts so the type is evident
- Use inline initialization for class member variables
- Use `= default` for empty constructors / destructors
- Use `using` in place of `typedef`
Reviewers: sbc100, tlively, aardappel
Subscribers: dschuff, sunfish, jgravelle-google, yurydelendik, kripken, MatzeB, mgorny, rupprecht, llvm-commits
Differential Revision: https://reviews.llvm.org/D57500
llvm-svn: 353075
Summary:
This switches the EH implementation to the new proposal:
https://github.com/WebAssembly/exception-handling/blob/master/proposals/Exceptions.md
(The previous proposal was
https://github.com/WebAssembly/exception-handling/blob/master/proposals/old/Exceptions.md)
- Instruction changes
- Now we have one single `catch` instruction that returns a except_ref
value
- `throw` now can take variable number of operations
- `rethrow` does not have 'depth' argument anymore
- `br_on_exn` queries an except_ref to see if it matches the tag and
branches to the given label if true.
- `extract_exception` is a pseudo instruction that simulates popping
values from wasm stack. This is to make `br_on_exn`, a very special
instruction, work: `br_on_exn` puts values onto the stack only if it
is taken, and the # of values can vay depending on the tag.
- Now there's only one `catch` per `try`, this patch removes all special
handling for terminate pad with a call to `__clang_call_terminate`.
Before it was the only case there are two catch clauses (a normal
`catch` and `catch_all` per `try`).
- Make `rethrow` act as a terminator like `throw`. This splits BB after
`rethrow` in WasmEHPrepare, and deletes an unnecessary `unreachable`
after `rethrow` in LateEHPrepare.
- Now we stop at all catchpads (because we add wasm `catch` instruction
that catches all exceptions), this creates new
`findWasmUnwindDestinations` function in SelectionDAGBuilder.
- Now we use `br_on_exn` instrution to figure out if an except_ref
matches the current tag or not, LateEHPrepare generates this sequence
for catch pads:
```
catch
block i32
br_on_exn $__cpp_exception
end_block
extract_exception
```
- Branch analysis for `br_on_exn` in WebAssemblyInstrInfo
- Other various misc. changes to switch to the new proposal.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D57134
llvm-svn: 352598
Summary:
Implements custom lowering logic that finds the optimal value for the
initial splat of the vector and either uses it or uses v128.const if
it is available and if it would produce smaller code. This logic
replaces large TableGen ISEL patterns that would lower all non-splat
BUILD_VECTORs into a splat followed by a fixed number of replace_lane
instructions. This CL fixes PR39685.
Reviewers: aheejin
Subscribers: dschuff, sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D56633
llvm-svn: 352592