26 Commits

Author SHA1 Message Date
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
Andy Wingo
159bb43ce8 [WebAssembly] Swap operand order of call_indirect in text format
The WebAssembly text and binary formats have different operand orders
for the "type" and "table" fields of call_indirect (and
return_call_indirect).  In LLVM we use the binary order for the MCInstr,
but when we produce or consume the text format we should use the text
order.  For compilation units targetting WebAssembly 1.0 (without the
reference types feature), we omit the table operand entirely.

Differential Revision: https://reviews.llvm.org/D97761
2021-03-03 08:51:21 +01:00
Andy Wingo
d9c224e71b [WebAssembly] call_indirect issues table number relocs
If the reference-types feature is enabled, call_indirect will explicitly
reference its corresponding function table via TABLE_NUMBER
relocations against a table symbol.

Also, as before, address-taken functions can also cause the function
table to be created, only with reference-types they additionally cause a
symbol table entry to be emitted.

Differential Revision: https://reviews.llvm.org/D90948
2021-03-01 16:49:00 +01:00
Dan Gohman
674189ca78 [WebAssembly] Avoid bit_cast when printing f32 and f64 immediates
Use `APInt` to convert a 32-bit or 64-bit immediate to an `APFloat` rather than
`bit_cast` to a `float` or `double` to avoid going through host floating-point and
potentially changing the bit pattern of NaNs.

Differential Revision: https://reviews.llvm.org/D97490
2021-02-26 14:19:02 -08:00
Andy Wingo
e4dd319951 Revert "[WebAssembly] call_indirect issues table number relocs"
This reverts commit 861dbe1a021e6439af837b72b219fb9c449a57ae.  It broke
emscripten -- see https://reviews.llvm.org/D90948#2578843.
2021-02-23 11:48:08 +01:00
Andy Wingo
4c62f39d2f [WebAssembly] call_indirect issues table number relocs
If the reference-types feature is enabled, call_indirect will explicitly
reference its corresponding function table via `TABLE_NUMBER`
relocations against a table symbol.

Also, as before, address-taken functions can also cause the function
table to be created, only with reference-types they additionally cause a
symbol table entry to be emitted.

We abuse the used-in-reloc flag on symbols to indicate which tables
should end up in the symbol table.  We do this because unfortunately
older wasm-ld will carp if it see a table symbol.

Differential Revision: https://reviews.llvm.org/D90948
2021-02-22 10:13:36 +01:00
Heejin Ahn
4214250471 [WebAssemblly] Fix rethrow's argument computation
Previously we assumed `rethrow`'s argument was always 0, but it turned
out `rethrow` follows the same rule with `br` or `delegate`:
https://github.com/WebAssembly/exception-handling/pull/137
https://github.com/WebAssembly/exception-handling/issues/146#issuecomment-777349038

Currently `rethrow`s generated by our backend always rethrow the
exception caught by the innermost enclosing catch, so this adds a
function to compute that and replaces `rethrow`'s argument with its
computed result.

This also renames `EHPadStack` in `InstPrinter` to `TryStack`, because
in CFGStackify we use `EHPadStack` to mean the range between
`catch`~`end`, while in `InstPrinter` we used it to mean the range
between `try`~`catch`, so choosing different names would look clearer.
Doesn't contain any functional changes in `InstPrinter`.

Reviewed By: dschuff

Differential Revision: https://reviews.llvm.org/D96595
2021-02-13 03:43:15 -08:00
Heejin Ahn
3c77486de7 [WebAssembly] Fix delegate's argument computation
I previously assumed `delegate`'s immediate argument computation
followed a different rule than that of branches, but we agreed to make
it the same
(https://github.com/WebAssembly/exception-handling/issues/146). This
removes the need for a separate `DelegateStack` in both CFGStackify and
InstPrinter.

When computing the immediate argument, we use a different function for
`delegate` computation because in MIR `DELEGATE`'s instruction's
destination is the destination catch BB or delegate BB, and when it is a
catch BB, we need an additional step of getting its corresponding `end`
marker.

Reviewed By: tlively, dschuff

Differential Revision: https://reviews.llvm.org/D96525
2021-02-11 21:57:28 -08:00
Heejin Ahn
91168a9374 [WebAssembly] Update InstPrinter and AsmParser for new EH instructions
This updates InstPrinter and AsmParser for `delegate` and `catch_all`
instructions. Both will reject programs with multiple `catch_all`s per a
single `try`. And InstPrinter uses `EHInstStack` to figure out whether
to print catch label comments: It does not print catch label comments
for second `catch` or `catch_all` in a `try`.

Reviewed By: aardappel

Differential Revision: https://reviews.llvm.org/D94051
2021-02-06 08:54:56 -08:00
Heejin Ahn
cf51144c01 [WebAssembly] Fix call unwind mismatches
This adds `delegate` instruction and use it to fix unwind destination
mismatches created by marker placement in CFGStackify.

There are two kinds of unwind destination mismatches:
- Mismatches caused by throwing instructions (here we call it "call
  unwind mismatches", even though `throw` and `rethrow` can also cause
  mismatches)
- Mismatches caused by `catch`es, in case a foreign exception is not
  caught by the nearest `catch` and the next outer `catch` is not the
  catch it should unwind to. This kind of mismatches didn't exist in the
  previous version of the spec, because in the previous spec `catch` was
  effectively `catch_all`, catching all exceptions.

This implements routines to fix the first kind of unwind mismatches,
which we call "call unwind mismatches". The second mismatch (catch
unwind mismatches) will be fixed in a later CL.

This also reenables all previously disabled tests in cfg-stackify-eh.ll
and updates FileCheck lines to match the new spec. Two tests were
deleted because they specifically tested the way we fixed unwind
mismatches before using `exnref`s and branches, which we don't do
anymore.

Reviewed By: tlively

Differential Revision: https://reviews.llvm.org/D94048
2021-02-06 07:07:04 -08:00
Dan Gohman
1471de1de2 [WebAssembly] Support single-floating-point immediate value
As mentioned in TODO comment, casting double to float causes NaNs to change bits.
To avoid the change, this patch adds support for single-floating-point immediate value on MachineCode.

Patch by Yuta Saito.

Differential Revision: https://reviews.llvm.org/D77384
2021-02-04 18:05:06 -08:00
Sam Clegg
a3e0bfc296 Revert "[WebAssembly] call_indirect issues table number relocs"
This reverts commit 418df4a6ab35d343cc0f2608c90a73dd9b8d0ab1.

This change broke emscripten tests, I believe because it started
generating 5-byte a wide table index in the call_indirect instruction.
Neither v8 nor wabt seem to be able to handle that.  The spec
currently says that this is single 0x0 byte and:

"In future versions of WebAssembly, the zero byte occurring in the
encoding of the call_indirectcall_indirect instruction may be used to
index additional tables."

So we need to revisit this change.  For backwards compat I guess
we need to guarantee that __indirect_function_table is always at
address zero.   We could also consider making this a single-byte
relocation with and assert if have more than 127 tables (for now).

Differential Revision: https://reviews.llvm.org/D95005
2021-01-19 15:06:07 -08:00
Andy Wingo
6ddb7e7525 [WebAssembly] call_indirect issues table number relocs
This patch changes to make call_indirect explicitly refer to the
corresponding function table, residualizing TABLE_NUMBER relocs against
it.

With this change, wasm-ld now sees all references to tables, and can
link multiple tables.

Differential Revision: https://reviews.llvm.org/D90948
2021-01-19 09:32:45 +01:00
Heejin Ahn
3017c7dd86 [WebAssembly] Update InstPrinter support for EH
- Updates InstPrinter to handle `catch_all`.
- Makes `rethrow` condition an early exit from the function to make the
  rest simpler.
- Unify label and catch counters. They don't need to be counted
  separately and this will help `delegate` instruction later.
- Removes `LastSeenEHInst` field. This was first introduced to handle
  when there are more than one `catch` blocks per `try`, but this was
  not implemented correctly and not being used at the moment anyway.
- Reenables all tests in cfg-stackify-eh.ll that don't deal with unwind
  destination mismatches, which will be handled in a later CL.

Reviewed By: dschuff, tlively, aardappel

Differential Revision: https://reviews.llvm.org/D94043
2021-01-09 02:42:35 -08:00
Heejin Ahn
ecf1f07299 [WebAssembly] Remove exnref and br_on_exn
This removes `exnref` type and `br_on_exn` instruction. This is
effectively NFC because most uses of these were already removed in the
previous CLs.

Reviewed By: dschuff, tlively

Differential Revision: https://reviews.llvm.org/D94041
2021-01-09 02:02:54 -08:00
Andy Wingo
d85c4c569d [WebAssembly] Implement ref.null
This patch adds a new "heap type" operand kind to the WebAssembly MC
layer, used by ref.null. Currently the possible values are "extern" and
"func"; when typed function references come, though, this operand may be
a type index.

Note that the "heap type" production is still known as "refedtype" in
the draft proposal; changing its name in the spec is
ongoing (https://github.com/WebAssembly/reference-types/issues/123).

The register form of ref.null is still untested.

Differential Revision: https://reviews.llvm.org/D90608
2020-11-03 10:46:23 -08:00
Paulo Matos
e24680c852 [WebAssembly] Added .tabletype to asm and multiple table support in obj files
Adds more testing in basic-assembly.s and a new test tables.s.
Adds support to yaml reading and writing of tables as well.

Differential Revision: https://reviews.llvm.org/D88815
2020-10-13 07:52:23 -07:00
Thomas Lively
bd828c852a [WebAssembly] Replace all calls with generalized multivalue calls
Summary:
Extends the multivalue call infrastructure to tail calls, removes all
legacy calls specialized for particular result types, and removes the
CallIndirectFixup pass, since all indirect call arguments are now
fixed up directly in the post-insertion hook.

In order to keep supporting pretty-printed defs and uses in test
expectations, MCInstLower now inserts an immediate containing the
number of defs for each call and call_indirect. The InstPrinter is
updated to query this immediate if it is present and determine which
MCOperands are defs and uses accordingly.

Depends on D72902.

Reviewers: aheejin

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

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D74192
2020-02-18 15:55:20 -08:00
Fangrui Song
0523ceb321 [MC] Add parameter Address to MCInstrPrinter::printInstruction
Follow-up of D72172.

Reviewed By: jhenderson, rnk

Differential Revision: https://reviews.llvm.org/D72180
2020-01-06 20:44:14 -08:00
Fangrui Song
00f5c66666 [MC] Add parameter Address to MCInstPrinter::printInst
printInst prints a branch/call instruction as `b offset` (there are many
variants on various targets) instead of `b address`.

It is a convention to use address instead of offset in most external
symbolizers/disassemblers. This difference makes `llvm-objdump -d`
output unsatisfactory.

Add `uint64_t Address` to printInst(), so that it can pass the argument to
printInstruction(). `raw_ostream &OS` is moved to the last to be
consistent with other print* methods.

The next step is to pass `Address` to printInstruction() (generated by
tablegen from the instruction set description). We can gradually migrate
targets to print addresses instead of offsets.

In any case, downstream projects which don't know `Address` can pass 0 as
the argument.

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D72172
2020-01-06 20:42:22 -08:00
Thomas Lively
5d88a6a71d [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
4be6d4a9bc [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
Wouter van Oortmerssen
83a02771fb [WebAssembly] Assembler/InstPrinter: support call_indirect type index.
A TYPE_INDEX operand (as used by call_indirect) used to be represented
by the InstPrinter as a symbol (e.g. .Ltype_index0@TYPE_INDEX) which
was a bit of a mismatch with the WasmObjectWriter which expects an
unnamed symbol, to receive the signature from and then turn into a
reloc.

There was really no good way to round-trip this information. An earlier
version of this patch tried to attach the signature information using
a .functype, but that ran into trouble when the symbol was re-emitted
without a name. Removing the name was a giant hack also.

The current version changes the assembly syntax to have an inline
signature spec for TYPEINDEX operands that is always unnamed, which
is much more elegant both in syntax and in implementation (as now the
assembler is able to follow the same path as the regular backend)

Reviewers: sbc100, dschuff, aheejin, jgravelle-google, sunfish, tlively

Subscribers: arphaman, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D64758

llvm-svn: 367590
2019-08-01 18:08:26 +00:00
Rui Ueyama
1179e18f0c Fix parameter name comments using clang-tidy. NFC.
This patch applies clang-tidy's bugprone-argument-comment tool
to LLVM, clang and lld source trees. Here is how I created this
patch:

$ git clone https://github.com/llvm/llvm-project.git
$ cd llvm-project
$ mkdir build
$ cd build
$ cmake -GNinja -DCMAKE_BUILD_TYPE=Debug \
    -DLLVM_ENABLE_PROJECTS='clang;lld;clang-tools-extra' \
    -DCMAKE_EXPORT_COMPILE_COMMANDS=On -DLLVM_ENABLE_LLD=On \
    -DCMAKE_C_COMPILER=clang -DCMAKE_CXX_COMPILER=clang++ ../llvm
$ ninja
$ parallel clang-tidy -checks='-*,bugprone-argument-comment' \
    -config='{CheckOptions: [{key: StrictMode, value: 1}]}' -fix \
    ::: ../llvm/lib/**/*.{cpp,h} ../clang/lib/**/*.{cpp,h} ../lld/**/*.{cpp,h}

llvm-svn: 366177
2019-07-16 04:46:31 +00:00
Heejin Ahn
2b18b87f2b [WebAssembly] Rename except_ref type to exnref
Summary:
We agreed to rename `except_ref` to `exnref` for consistency with other
reference types in
https://github.com/WebAssembly/exception-handling/issues/79. This also
renames WebAssemblyInstrExceptRef.td to WebAssemblyInstrRef.td in order
to use the file for other reference types in future.

Reviewers: dschuff

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

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D64703

llvm-svn: 366145
2019-07-15 22:49:25 +00:00
David L. Jones
e4f7d3295f [WebAssembly] Move InstPrinter files to MCTargetDesc. NFC
For some targets, there is a circular dependency between InstPrinter and
MCTargetDesc. Merging them together will fix this. For the other targets,
the merging is to maintain consistency so all targets will have the same
structure.

llvm-svn: 360550
2019-05-13 03:32:41 +00:00