Summary:
Irreducible control flow is not that rare, e.g. it happens in malloc and
3 other places in the libc portions linked in to a hello world program.
This patch improves how we handle that code: it emits a br_table to
dispatch to only the minimal necessary number of blocks. This reduces
the size of malloc by 33%, and makes it comparable in size to asm2wasm's
malloc output.
Added some tests, and verified this passes the emscripten-wasm tests run
on the waterfall (binaryen2, wasmobj2, other).
Reviewers: aheejin, sunfish
Subscribers: mgrang, jgravelle-google, sbc100, dschuff, llvm-commits
Differential Revision: https://reviews.llvm.org/D55467
Patch by Alon Zakai (kripken)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@350367 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This is a code size savings and is also important to get runnable code
while engines do not support v128.const.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D55910
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@349724 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Gates v128.const, f32x4.sqrt, f32x4.div, i8x16.extract_lane_u, and
i16x8.extract_lane_u on the --wasm-enable-unimplemented-simd flag,
since these ops are not implemented yet in V8.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D55904
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@349720 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
We use `variable_ops` in the tablegen defs to denote the list of
branch targets in `br_table`, but unlike other uses of `variable_ops`
(e.g. call) the these branch targets need to actually be encoded in the
instruction. The existing tables for `variable_ops` cause not operands
to be accepted by the assembly matcher.
Following the example of ARM:
https://github.com/llvm-mirror/llvm/blob/2cc0a7da876c1d8c32775b0119e1e15aaa759b9e/lib/Target/ARM/ARMInstrInfo.td#L550-L555
we introduce a new operand type to capture this list, and we use the
same {} syntax as ARM as well to differentiate them from regular
integer operands.
Also removed definition and use of TSFlags in tablegen defs, since
`br_table` now has a non-variable_ops immediate operand, so the
previous logic of only the variable_ops arguments being labels didn't
make sense anymore.
Reviewers: dschuff, aheejin, sunfish
Subscribers: javed.absar, sbc100, jgravelle-google, kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D55401
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@349405 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This patch supports `.eventtype` directive printing and parsing in the
same syntax with `.functype`.
Reviewers: aardappel, sbc100
Subscribers: dschuff, sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D55353
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@348818 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This makes it easier/cleaner to generate a single signature from
this directive. Also:
- Adds the symbol name, such that we don't depend on the location
of this directive anymore.
- Actually constructs the signature in the assembler, and make the
assembler own it.
- Refactor the use of MVT vs ValType in the streamer and assembler
to require less conversions overall.
- Changed 700 or so tests to use it.
Reviewers: sbc100, dschuff
Subscribers: jgravelle-google, eraman, aheejin, sunfish, jfb, llvm-commits
Differential Revision: https://reviews.llvm.org/D54652
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@347228 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
`throw` instruction is a terminator in wasm, but BBs were not splitted
after `throw` instructions, causing machine instruction verifier to
fail.
This patch
- Splits BBs after `throw` instructions in WasmEHPrepare and adding an
unreachable instruction after `throw`, which will be deleted in
LateEHPrepare pass
- Refactors WasmEHPrepare into two member functions
- Changes the semantics of `eraseBBsAndChildren` in LateEHPrepare pass
to match that of WasmEHPrepare pass, which is newly added. Now
`eraseBBsAndChildren` does not delete BBs with remaining predecessors.
- Fixes style nits, making static function names conform to clang-tidy
- Re-enables the test temporarily disabled by rL346840 && rL346845
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D54571
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@347003 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This adds support for the 'event section' specified in the exception
handling proposal. (This was named 'exception section' first, but later
renamed to 'event section' to take possibilities of other kinds of
events into consideration. But currently we only store exception info in
this section.)
The event section is added between the global section and the export
section. This is for ease of validation per request of the V8 team.
This patch:
- Creates the event symbol type, which is a weak symbol
- Makes 'throw' instruction take the event symbol '__cpp_exception'
- Adds relocation support for events
- Adds WasmObjectWriter / WasmObjectFile (Reader) support
- Adds obj2yaml / yaml2obj support
- Adds '.eventtype' printing support
Reviewers: dschuff, sbc100, aardappel
Subscribers: jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D54096
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346825 91177308-0d34-0410-b5e6-96231b3b80d8
Usually MIPS hosts uses a legacy (non IEEE 754-2008) encoding for NaNs.
Tests like `nan_f32` failed in attempt to compare hard-coded IEEE
754-2008 NaN value and a legacy NaN value provided by a system.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346773 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This is to replace the ELFAsmParser that WebAssembly was using, which
so far was a stub that didn't do anything, and couldn't work correctly
with wasm.
This new class is there to implement generic directives related to
wasm as a binary format. Wasm target specific directives are still
parsed in WebAssemblyAsmParser as before. The two classes now
cooperate more correctly too.
Also implemented .result which was missing. Any unknown directives
will now result in errors.
Reviewers: dschuff, sbc100
Subscribers: mgorny, jgravelle-google, eraman, aheejin, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D54360
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346700 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
These tests fail on 32-bit builds because NaN payload bits in floating point
immediates are not necessarily preserved through compilation. This is because
the MC layer uses native doubles to store these values. The tests will be
reenabled once this problem has been fixed or deleted if we decide we don't care
about lowering payload bits.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D54353
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346558 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
The pass incorrectly assumed if there's a longjmp declaration in the
module, there is also a setjmp function declaration. Fixed it, and now
the pass only converts longjmp and does not do any other transformation
when there's no setjmp declaration in the module.
Fixes PR39562.
Reviewers: jgravelle-google, sbc100
Subscribers: dschuff, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D54273
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346445 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts rL345880. It caused some test failures on the
webassembly waterfall. e.g. binaryen2.test_mainenv fails due
the fact that `envp` ends up being undef rather than 0.
Differential Revision: https://reviews.llvm.org/D54117
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346187 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
EH stack depth is incremented at `try` and decremented at `catch`. When
there are more than two catch instructions for a try instruction, we
shouldn't count non-first catches when calculating EH stack depths.
This patch fixes two bugs:
- CFGStackify: Exclude `catch_all` in the terminate catch pad when
calculating EH pad stack, because when we have multiple catches for a
try we should count only the first catch instruction when calculating
EH pad stack.
- InstPrinter: The initial intention was also to exclude non-first
catches, but it didn't account nested try-catches, so it failed on
this case:
```
try
try
catch
end
catch <-- (1)
end
```
In the example, when we are at the catch (1), the last seen EH
instruction is not `try` but `end_try`, violating the wrong assumption.
We don't need these after we switch to the second proposal because there
is gonna be only one `catch` instruction. But anyway before then these
bugfixes are necessary for keep trunk in working state.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D53819
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346029 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Assembly output can use globals like __stack_pointer implicitly,
but has no way of indicating the type of such a global, which makes
it hard for tools processing it (such as the MC Assembler) to
reconstruct this information.
The improved assembler directives parsing (in progress in
https://reviews.llvm.org/D53842) will make use of this information.
Also deleted code for the .import_global directive which was unused.
New test case in userstack.ll
Reviewers: dschuff, sbc100
Subscribers: jgravelle-google, aheejin, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D54012
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@345917 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Also reduce the test case for implicit defs and test it with all
register classes.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D53855
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@345794 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This adds support for LSDA (exception table) generation for wasm EH.
Wasm EH mostly follows the structure of Itanium-style exception tables,
with one exception: a call site table entry in wasm EH corresponds to
not a call site but a landing pad.
In wasm EH, the VM is responsible for stack unwinding. After an
exception occurs and the stack is unwound, the control flow is
transferred to wasm 'catch' instruction by the VM, after which the
personality function is called from the compiler-generated code. (Refer
to WasmEHPrepare pass for more information on this part.)
This patch:
- Changes wasm.landingpad.index intrinsic to take a token argument, to
make this 1:1 match with a catchpad instruction
- Stores landingpad index info and catch type info MachineFunction in
before instruction selection
- Lowers wasm.lsda intrinsic to an MCSymbol pointing to the start of an
exception table
- Adds WasmException class with overridden methods for table generation
- Adds support for LSDA section in Wasm object writer
Reviewers: dschuff, sbc100, rnk
Subscribers: mgorny, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D52748
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@345345 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Currently InstPrinter ignores if there are mismatches between block/loop
and end markers by skipping the case if ControlFlowStack is empty. I
guess it is better to explicitly error out in this case, because this
signals invalid input.
Reviewers: aardappel
Subscribers: dschuff, sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D53620
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@345333 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Currently when assigning depths 'rethrow' does not take the whole
control flow stack into accounts but only considers EH pad stacks. When
assigning depth immmediates to rethrows, in normal cases it is done
correctly but when a rethrow instruction throws up to a caller, i.e., we
convert a pseudo RETHROW_TO_CALLER instruction to a rethrow, it
mistakenly compute the whole stack depth.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D53619
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@345223 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Changing the node type in lowering was violating assumptions made in
the DAG combiner, so don't change the node type any more. This fixes
one of the issues reported in bug 39275.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits, alexcrichton
Differential Revision: https://reviews.llvm.org/D53537
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@345221 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Due to previous work to make WebAssembly MC by default stack-only
inline assembly now "just works" (previously it didn't since it had
no way to know types of registers), so no further work required.
So far we only have tests (in inline-asm.ll) which test with
non-existing instructions, so this adds a test that roundtrips
both the inline assembly and its surrounding code thru the assembler.
Reviewers: dschuff, sunfish
Subscribers: sbc100, jgravelle-google, eraman, aheejin, llvm-commits
Differential Revision: https://reviews.llvm.org/D52914
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@344977 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Undefined indices in shuffles can be used when not all lanes of the
output vector will be used. This happens for example in the expansion
of vector reduce operations. Regardless, undefs are legal as lane
indices in IR and should be supported.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D53057
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@344803 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit r344575.
Newly introduced test eh-lsda.ll.test fails with use-after-free under
ASAN build.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@344639 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This adds support for LSDA (exception table) generation for wasm EH.
Wasm EH mostly follows the structure of Itanium-style exception tables,
with one exception: a call site table entry in wasm EH corresponds to
not a call site but a landing pad.
In wasm EH, the VM is responsible for stack unwinding. After an
exception occurs and the stack is unwound, the control flow is
transferred to wasm 'catch' instruction by the VM, after which the
personality function is called from the compiler-generated code. (Refer
to WasmEHPrepare pass for more information on this part.)
This patch:
- Changes wasm.landingpad.index intrinsic to take a token argument, to
make this 1:1 match with a catchpad instruction
- Stores landingpad index info and catch type info MachineFunction in
before instruction selection
- Lowers wasm.lsda intrinsic to an MCSymbol pointing to the start of an
exception table
- Adds WasmException class with overridden methods for table generation
- Adds support for LSDA section in Wasm object writer
Reviewers: dschuff, sbc100, rnk
Subscribers: mgorny, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D52748
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@344575 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Although the saturating float to int instructions are already
emitted from normal IR, the fpto{s,u}i instructions produce poison
values if the argument cannot fit in the result type. These intrinsics
are therefore necessary to get guaranteed defined saturating behavior.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D53004
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@344204 91177308-0d34-0410-b5e6-96231b3b80d8
Thomas Lively