Commit Graph

863 Commits

Author SHA1 Message Date
Wouter van Oortmerssen c7b89f0f62 [WebAssembly] Enforce assembler emits to streamer in order.
Summary:
The assembler processes directives and instructions in whatever order
they are in the file, then directly emits them to the streamer. This
could cause badly written (or generated) .s files to produce
incorrect binaries.

It now has state that tracks what it has most recently seen, to
enforce they are emitted in a given order that always produces
correct wasm binaries.

Also added a new test that compares obj2yaml output from llc (the
backend) to that going via .s and the assembler to ensure both paths
generate the same binaries.

The features this test covers could be extended.

Passes all wasm Lit tests.

Fixes: https://bugs.llvm.org/show_bug.cgi?id=39557

Reviewers: sbc100, dschuff, aheejin

Subscribers: jgravelle-google, sunfish, llvm-commits

Differential Revision: https://reviews.llvm.org/D55149

llvm-svn: 348185
2018-12-03 20:30:28 +00:00
Thomas Lively 66ea30c7bc [WebAssembly] Expand unavailable integer operations for vectors
Summary:
Expands for vector types all of the integer operations that are
expanded for scalars because they are not supported at all by
WebAssembly.

This CL has no tests because such tests would really be testing the
target-independent expansion, but I'm happy to add tests if reviewers
think it would be helpful.

Reviewers: aheejin, dschuff

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

Differential Revision: https://reviews.llvm.org/D55010

llvm-svn: 347923
2018-11-29 22:01:01 +00:00
Sam Clegg 4791a668f5 [WebAssembly] WebAssemblyLowerEmscriptenEHSjLj: use getter/setter for accessing tempRet0
Rather than assuming that `tempRet0` exists in linear memory only assume
the getter/setter functions exist.  This avoids conflicting with
binaryen which declares a wasm global for this purpose and defines it's
own getter and setter for that.

The other advantage of doing things this way is that it leaving
it up to the linker/finalizer to decide how to actually store this
temporary.  As it happens binaryen uses a wasm global which is more
appropriate since it is thread safe.

This also allows us to change the way this is stored in the future
(memory, TLS memory, wasm global) without modifying LLVM.

This is part of a 4 part change:
LLVM: https://reviews.llvm.org/D53240
fastcomp: https://github.com/kripken/emscripten-fastcomp/pull/237
emscripten: https://github.com/kripken/emscripten/pull/7358
binaryen: https://github.com/WebAssembly/binaryen/pull/1709

Differential Revision: https://reviews.llvm.org/D53240

llvm-svn: 347340
2018-11-20 19:25:07 +00:00
Wouter van Oortmerssen 49482f824a [WebAssembly] replaced .param/.result by .functype
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

llvm-svn: 347228
2018-11-19 17:10:36 +00:00
Heejin Ahn e0f8b9bfc6 [WebAssembly] Add null streamer support
Summary: Now `llc -filetype=null` works.

Reviewers: eush

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

Differential Revision: https://reviews.llvm.org/D54660

llvm-svn: 347155
2018-11-18 11:58:47 +00:00
Sam Clegg 74f5fd4e32 [WebAssembly] Default to static reloc model
Differential Revision: https://reviews.llvm.org/D54637

llvm-svn: 347073
2018-11-16 18:59:51 +00:00
Heejin Ahn 095796a391 [WebAssembly] Split BBs after throw instructions
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

llvm-svn: 347003
2018-11-16 00:47:18 +00:00
Thomas Lively fc3163b67a [WebAssembly] Fix return type of nextByte
Summary:
The old return type did not allow for correct error reporting and was
causing a compiler warning.

Reviewers: aheejin

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

Differential Revision: https://reviews.llvm.org/D54586

llvm-svn: 346979
2018-11-15 18:56:49 +00:00
Thomas Lively 77b33c86f5 [WebAssembly] Renumber SIMD bitwise instructions
Summary: Changed to match https://github.com/WebAssembly/simd/pull/54.

Reviewers: aheejin

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

Differential Revision: https://reviews.llvm.org/D54561

llvm-svn: 346931
2018-11-15 03:38:59 +00:00
Heejin Ahn da419bdb5e [WebAssembly] Add support for the event section
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

llvm-svn: 346825
2018-11-14 02:46:21 +00:00
Sam Clegg f98ba05f3d [WebAssembly] Fix broken assumption that all bitcasts are to functions types
Specifically, we can bitcast to void.

Fixes PR39591

Differential Revision: https://reviews.llvm.org/D54447

llvm-svn: 346778
2018-11-13 19:14:02 +00:00
Wouter van Oortmerssen cc75e77df5 [WebAssembly] Added WasmAsmParser.
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

llvm-svn: 346700
2018-11-12 20:15:01 +00:00
Thomas Lively 936734b777 [WebAssembly] Update bleeding-edge cpu features
Reviewers: aheejin, dschuff

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

Differential Revision: https://reviews.llvm.org/D54362

llvm-svn: 346570
2018-11-10 00:11:14 +00:00
Fangrui Song 4955066366 [WebAssembly] Hotfix of WebAssemblyInstructionTableSize after rL346465
llvm-svn: 346535
2018-11-09 18:32:20 +00:00
Thomas Lively 2faf079494 [WebAssembly] Read prefixed opcodes as ULEB128s
Summary: Depends on D54126.

Reviewers: aheejin, dschuff, aardappel

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

Differential Revision: https://reviews.llvm.org/D54138

llvm-svn: 346465
2018-11-09 01:57:00 +00:00
Thomas Lively 4ddd22581e [WebAssembly][NFC] Reorder SIMD section
Summary:
Reorders the sections in the SIMD tablegen file to roughly match the
new opcode ordering. Depends on D54126.

Reviewers: aheejin, dschuff

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

Differential Revision: https://reviews.llvm.org/D54134

llvm-svn: 346464
2018-11-09 01:49:19 +00:00
Thomas Lively 299d214aba [WebAssembly] Renumber and LEB128-encode SIMD opcodes
Reviewers: aheejin, dschuff, aardappel

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

Differential Revision: https://reviews.llvm.org/D54126

llvm-svn: 346463
2018-11-09 01:45:56 +00:00
Thomas Lively 38c902bc2e [WebAssembly] Lower select for vectors
Summary:

Reviewers: aheejin, dschuff

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

Differential Revision: https://reviews.llvm.org/D53675

llvm-svn: 346462
2018-11-09 01:38:44 +00:00
Heejin Ahn 0c68a875fa [WebAssembly] Fix LowerEmscriptenEHSjLj when there's only longjmp
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

llvm-svn: 346445
2018-11-08 22:56:26 +00:00
Thomas Lively 897171902b [WebAssembly] Add V128 to WebAssemblyInstrInfo::copyPhysReg
Reviewers: aheejin, dschuff

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

Differential Revision: https://reviews.llvm.org/D53872

llvm-svn: 346384
2018-11-08 02:35:28 +00:00
Sam Clegg 5292d17ec8 Revert "[WebAssembly] Fixup `main` signature by default"
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

llvm-svn: 346187
2018-11-06 00:31:02 +00:00
Wouter van Oortmerssen de28b5d17f [WebAssembly] Parsing missing directives to produce valid .o
Summary:
The assembler was able to assemble and then dump back to .s, but
was failing to parse certain directives necessary for valid .o
output:
- .type directives are now recognized to distinguish function symbols
  and others.
- .size is now parsed to provide function size.
- .globaltype (introduced in https://reviews.llvm.org/D54012) is now
  recognized to ensure symbols like __stack_pointer have a proper type
  set for both .s and .o output.

Also added tests for the above.

Reviewers: sbc100, dschuff

Subscribers: jgravelle-google, aheejin, dexonsmith, kristina, llvm-commits, sunfish

Differential Revision: https://reviews.llvm.org/D53842

llvm-svn: 346047
2018-11-02 22:04:33 +00:00
Heejin Ahn 5b023e07ea [WebAssembly] Fix bugs in rethrow depth counting and InstPrinter
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

llvm-svn: 346029
2018-11-02 18:38:52 +00:00
Wouter van Oortmerssen 3231e518a3 [WebAssembly] Added a .globaltype directive to .s output.
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

llvm-svn: 345917
2018-11-02 00:45:00 +00:00
Thomas Lively b2382c8bf7 [WebAssembly] General vector shift lowering
Summary: Adds support for lowering non-splat shifts.

Reviewers: aheejin, dschuff

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

Differential Revision: https://reviews.llvm.org/D53625

llvm-svn: 345916
2018-11-02 00:39:57 +00:00
Thomas Lively fb84fd7c8e [WebAssembly] Expand inserts and extracts with variable indices
Reviewers: aheejin, dschuff

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

Differential Revision: https://reviews.llvm.org/D53964

llvm-svn: 345913
2018-11-02 00:06:56 +00:00
Heejin Ahn 2e398976ba [WebAssembly] Fix signature parsing for 'try' in AsmParser
Summary:
Like `block` or `loop`, `try` can take an optional signature which can
be omitted. This patch allows `try`'s signature to be omitted. Also
added some tests for EH instructions.

Reviewers: aardappel

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

Differential Revision: https://reviews.llvm.org/D53873

llvm-svn: 345888
2018-11-01 20:32:15 +00:00
Reid Kleckner 4dc0b1ac60 Fix clang -Wimplicit-fallthrough warnings across llvm, NFC
This patch should not introduce any behavior changes. It consists of
mostly one of two changes:
1. Replacing fall through comments with the LLVM_FALLTHROUGH macro
2. Inserting 'break' before falling through into a case block consisting
   of only 'break'.

We were already using this warning with GCC, but its warning behaves
slightly differently. In this patch, the following differences are
relevant:
1. GCC recognizes comments that say "fall through" as annotations, clang
   doesn't
2. GCC doesn't warn on "case N: foo(); default: break;", clang does
3. GCC doesn't warn when the case contains a switch, but falls through
   the outer case.

I will enable the warning separately in a follow-up patch so that it can
be cleanly reverted if necessary.

Reviewers: alexfh, rsmith, lattner, rtrieu, EricWF, bollu

Differential Revision: https://reviews.llvm.org/D53950

llvm-svn: 345882
2018-11-01 19:54:45 +00:00
Sam Clegg ddf049869a [WebAssembly] Fixup `main` signature by default
Differential Revision: https://reviews.llvm.org/D53396

llvm-svn: 345880
2018-11-01 19:38:44 +00:00
Thomas Lively d4891a1b7a [WebAssembly] Lower vselect
Reviewers: aheejin, dschuff

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

Differential Revision: https://reviews.llvm.org/D53630

llvm-svn: 345797
2018-11-01 00:01:02 +00:00
Thomas Lively b61232eacd [WebAssembly] Process p2align operands for SIMD loads and stores
Reviewers: aheejin, dschuff

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

Differential Revision: https://reviews.llvm.org/D53886

llvm-svn: 345795
2018-10-31 23:58:20 +00:00
Thomas Lively 6ff31fe34d [WebAssembly] Handle vector IMPLICIT_DEFs.
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

llvm-svn: 345794
2018-10-31 23:50:53 +00:00
Thomas Lively eb15d00193 [WebAssembly] Lower away condition truncations for scalar selects
Reviewers: aheejin, dschuff

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

Differential Revision: https://reviews.llvm.org/D53676

llvm-svn: 345521
2018-10-29 18:38:12 +00:00
Heejin Ahn 24faf859e5 Reland "[WebAssembly] LSDA info generation"
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

llvm-svn: 345345
2018-10-25 23:55:10 +00:00
Heejin Ahn 3103d3dcd1 [WebAssembly] Support EH instructions in InstPrinter
Summary: This adds support for exception handling instructions to InstPrinter.

Reviewers: dschuff, aardappel

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

Differential Revision: https://reviews.llvm.org/D53634

llvm-svn: 345343
2018-10-25 23:45:48 +00:00
Heejin Ahn 1d13e6be37 Address comments
- Add llvm-mc test case (and delete the old one)
- Change report_fatal_error to assertions

llvm-svn: 345334
2018-10-25 23:35:14 +00:00
Heejin Ahn 1147d91402 [WebAssembly] Error out when block/loop markers mismatch
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

llvm-svn: 345333
2018-10-25 23:35:13 +00:00
Thomas Lively 0aad98fd07 [WebAssembly] Use target-independent saturating add
Reviewers: aheejin, dschuff

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

Differential Revision: https://reviews.llvm.org/D53721

llvm-svn: 345299
2018-10-25 19:06:13 +00:00
Thomas Lively 325c9c5e84 [WebAssembly] Set LoadExt and TruncStore actions for SIMD types
Summary: Fixes part of the problem reported in bug 39275.

Reviewers: aheejin, dschuff

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

Differential Revision: https://reviews.llvm.org/D53542

llvm-svn: 345230
2018-10-25 01:46:07 +00:00
Heejin Ahn ac764aa88e [WebAssembly] Fix immediate of rethrow when throwing to caller
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

llvm-svn: 345223
2018-10-24 23:31:24 +00:00
Thomas Lively ed9513472c [WebAssembly] Retain shuffle types during custom lowering
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

llvm-svn: 345221
2018-10-24 23:27:40 +00:00
Thomas Lively 30f1d69115 [NFC] Rename minnan and maxnan to minimum and maximum
Summary:
Changes all uses of minnan/maxnan to minimum/maximum
globally. These names emphasize that the semantic difference between
these operations is more than just NaN-propagation.

Reviewers: arsenm, aheejin, dschuff, javed.absar

Subscribers: jholewinski, sdardis, wdng, sbc100, jgravelle-google, jrtc27, atanasyan, llvm-commits

Differential Revision: https://reviews.llvm.org/D53112

llvm-svn: 345218
2018-10-24 22:49:55 +00:00
Sanjay Patel 47a52a0521 [WebAssembly] use 'match' to simplify code; NFC
Vector types are not possible here because this code explicitly
checks for a scalar type, but this is another step towards 
completely removing the fake binop queries for not/neg/fneg.

llvm-svn: 345043
2018-10-23 16:05:09 +00:00
Heejin Ahn a40303aa03 [WebAssembly] Fix assembly printing of br_table
Summary: In `br_table's stack version asm string, \t was missing.

Reviewers: aardappel

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

Differential Revision: https://reviews.llvm.org/D53516

llvm-svn: 344981
2018-10-23 00:28:14 +00:00
Thomas Lively c63b5fcb2a [WebAssembly][NFC] Remove WebAssemblyStackifier TableGen backend
Summary:
Replace its functionality with a TableGen InstrInfo relational
instruction mapping. Although arguably more complex than the TableGen
backend, the relational mapping is a smaller maintenance burden than a
TableGen backend.

Reviewers: aardappel, aheejin, dschuff

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

Differential Revision: https://reviews.llvm.org/D53307

llvm-svn: 344962
2018-10-22 21:55:26 +00:00
Thomas Lively 5ea17d450e [WebAssembly] Implement vector sext_inreg and tests with comparisons
Summary: Depends on D53251.

Reviewers: aheejin, dschuff

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

Differential Revision: https://reviews.llvm.org/D53252

llvm-svn: 344826
2018-10-20 01:35:23 +00:00
Thomas Lively 55735d522d [WebAssembly] Custom lower i64x2 constant shifts to avoid wrap
Summary: Depends on D53057.

Reviewers: aheejin, dschuff

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

Differential Revision: https://reviews.llvm.org/D53251

llvm-svn: 344825
2018-10-20 01:31:18 +00:00
Thomas Lively 11a332d08d [WebAssembly] Handle undefined lane indices in SIMD patterns
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

llvm-svn: 344803
2018-10-19 19:08:06 +00:00
Krasimir Georgiev 547d824da6 Revert "[WebAssembly] LSDA info generation"
This reverts commit r344575.
Newly introduced test eh-lsda.ll.test fails with use-after-free under
ASAN build.

llvm-svn: 344639
2018-10-16 18:50:09 +00:00
Heejin Ahn 0981eaab47 [WebAssembly] LSDA info generation
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

llvm-svn: 344575
2018-10-16 00:09:12 +00:00