Some instructions in WebAssembly trap for some inputs, which means that the
execution is terminated and (at least at the moment) a JavaScript exception is
thrown. Examples for traps are out-of-bounds memory accesses, or integer
divisions by zero.
Without the TrapIf and TrapUnless operators trap check in WebAssembly introduces 5
TurboFan nodes (branch, if_true, if_false, trap-reason constant, trap-position
constant), in addition to the trap condition itself. Additionally, each
WebAssembly function has four TurboFan nodes (merge, effect_phi, 2 phis) whose
number of inputs is linear to the number of trap checks in the function.
Especially for functions with high numbers of trap checks we observe a
significant slowdown in compilation time, down to 0.22 MiB/s in the sqlite
benchmark instead of the average of 3 MiB/s in other benchmarks. By introducing
a TrapIf common operator only a single node is necessary per trap check, in
addition to the trap condition. Also the nodes which are shared between trap
checks (merge, effect_phi, 2 phis) would disappear. First measurements suggest a
speedup of 30-50% on average.
This CL only implements TrapIf and TrapUnless on x64. The implementation is also
hidden behind the --wasm-trap-if flag.
Please take a special look at how the source position is transfered from the
instruction selector to the code generator, and at the context that is used for
the runtime call.
R=titzer@chromium.org
Review-Url: https://codereview.chromium.org/2562393002
Cr-Commit-Position: refs/heads/master@{#41720}
This adds more useful information to the v8-heap-stats tool.
BUG=v8:5489
Review-Url: https://codereview.chromium.org/2394213003
Cr-Commit-Position: refs/heads/master@{#40361}
[0xC] Convert to stack machine semantics.
[0xC] Use section codes instead of names.
[0xC] Add elements section decoding.
[0xC] Decoding of globals section.
[0xC] Decoding of memory section.
[0xC] Decoding of imports section.
[0xC] Decoding of exports section.
[0xC] Decoding of data section.
[0xC] Remove CallImport bytecode.
[0xC] Function bodies have an implicit block.
[0xC] Remove the bottom label from loops.
[0xC] Add signatures to blocks.
[0xC] Remove arities from branches.
Add tests for init expression decoding.
Rework compilation of import wrappers and how they are patched.
Rework function indices in debugging.
Fix ASM->WASM builder for stack machine.
Reorganize asm.js foreign functions due to import indices change.
R=ahaas@chromium.org,rossberg@chromium.org,bradnelson@chromium.org
BUG=chromium:575167
LOG=Y
Committed: https://crrev.com/76eb976a67273b8c03c744f64ad850b0432554b9
Review-Url: https://codereview.chromium.org/2345593003
Cr-Original-Commit-Position: refs/heads/master@{#39678}
Cr-Commit-Position: refs/heads/master@{#39795}
Reason for revert:
Main suspect for tsan:
https://build.chromium.org/p/client.v8/builders/V8%20Linux64%20TSAN/builds/11893
Also changes layout tests:
https://build.chromium.org/p/client.v8.fyi/builders/V8-Blink%20Linux%2064/builds/10036
+mips builder:
https://build.chromium.org/p/client.v8.ports/builders/V8%20Mips%20-%20builder/builds/4032
Original issue's description:
> [wasm] Master CL for Binary 0xC changes.
>
> [0xC] Convert to stack machine semantics.
> [0xC] Use section codes instead of names.
> [0xC] Add elements section decoding.
> [0xC] Decoding of globals section.
> [0xC] Decoding of memory section.
> [0xC] Decoding of imports section.
> [0xC] Decoding of exports section.
> [0xC] Decoding of data section.
> [0xC] Remove CallImport bytecode.
> [0xC] Function bodies have an implicit block.
> [0xC] Remove the bottom label from loops.
> [0xC] Add signatures to blocks.
> [0xC] Remove arities from branches.
> Add tests for init expression decoding.
> Rework compilation of import wrappers and how they are patched.
> Rework function indices in debugging.
> Fix ASM->WASM builder for stack machine.
> Reorganize asm.js foreign functions due to import indices change.
>
> R=ahaas@chromium.org,rossberg@chromium.org,bradnelson@chromium.org
> BUG=chromium:575167
> LOG=Y
>
> Committed: https://crrev.com/76eb976a67273b8c03c744f64ad850b0432554b9
> Cr-Commit-Position: refs/heads/master@{#39678}
TBR=ahaas@chromium.org,bradnelson@chromium.org,mtrofin@chromium.org,rossberg@chromium.org,bradnelson@google.com,titzer@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=chromium:575167
Review-Url: https://codereview.chromium.org/2361053004
Cr-Commit-Position: refs/heads/master@{#39685}
[0xC] Convert to stack machine semantics.
[0xC] Use section codes instead of names.
[0xC] Add elements section decoding.
[0xC] Decoding of globals section.
[0xC] Decoding of memory section.
[0xC] Decoding of imports section.
[0xC] Decoding of exports section.
[0xC] Decoding of data section.
[0xC] Remove CallImport bytecode.
[0xC] Function bodies have an implicit block.
[0xC] Remove the bottom label from loops.
[0xC] Add signatures to blocks.
[0xC] Remove arities from branches.
Add tests for init expression decoding.
Rework compilation of import wrappers and how they are patched.
Rework function indices in debugging.
Fix ASM->WASM builder for stack machine.
Reorganize asm.js foreign functions due to import indices change.
R=ahaas@chromium.org,rossberg@chromium.org,bradnelson@chromium.org
BUG=chromium:575167
LOG=Y
Review-Url: https://codereview.chromium.org/2345593003
Cr-Commit-Position: refs/heads/master@{#39678}
This is some initial cleanup to keep /src clean. The
AccountingAllocator is actually exclusively used by zones and this
common subfolder makes that more clear.
BUG=v8:5409
Review-Url: https://codereview.chromium.org/2344143003
Cr-Commit-Position: refs/heads/master@{#39558}
Reland of https://codereview.chromium.org/2034093002 (reverted by
https://codereview.chromium.org/2080153002).
Original commit message:
Implement WASM support on big-endian platforms. WASM has
an implicit requirement that it is running on little-endian
machine. We achieve WASM support on BE by keeping data
in memory in little-endian order, and changing data
endianness before storing to memory and after loading from
memory.
BUG=
Review-Url: https://codereview.chromium.org/2083523002
Cr-Commit-Position: refs/heads/master@{#37373}
Reason for revert:
[Sheriff] Speculative revert for crashes on chrubuntu chromebooks:
https://build.chromium.org/p/client.v8.ports/builders/V8%20Arm/builds/320
Original issue's description:
> Implement WASM big-endian support.
>
> Implement WASM support on big-endian platforms. WASM has
> an implicit requirement that it is running on little-endian
> machine. We achieve WASM support on BE by keeping data
> in memory in little-endian order, and changing data
> endianness before storing to memory and after loading from
> memory.
>
> BUG=
>
> Committed: https://crrev.com/d3f3f6c8186b2a53f0c539f7bba0c3708c4d83f9
> Cr-Commit-Position: refs/heads/master@{#37065}
TBR=titzer@chromium.org,akos.palfi@imgtec.com,balazs.kilvady@imgtec.com,jyan@ca.ibm.com,ivica.bogosavljevic@imgtec.com
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=
Review-Url: https://codereview.chromium.org/2080153002
Cr-Commit-Position: refs/heads/master@{#37091}
Implement WASM support on big-endian platforms. WASM has
an implicit requirement that it is running on little-endian
machine. We achieve WASM support on BE by keeping data
in memory in little-endian order, and changing data
endianness before storing to memory and after loading from
memory.
BUG=
Review-Url: https://codereview.chromium.org/2034093002
Cr-Commit-Position: refs/heads/master@{#37065}
This interpreter directly decodes and executes WASM binary code for
the purpose of supporting low-level debugging. It is not currently
integrated into the main WASM implementation.
R=ahaas@chromium.org,clemensh@chromium.org,rossberg@chromium.org,binji@chromium.org
BUG=
Review-Url: https://codereview.chromium.org/1972153002
Cr-Commit-Position: refs/heads/master@{#36497}
[wasm] Binary 11: br_table takes a value.
[wasm] Binary 11: Add implicit blocks to if arms.
[wasm] Binary 11: Add arities to call, return, and breaks
[wasm] Binary 11: Add experimental version.
This CL changes the encoder, decoder, and tests to use a postorder
encoding of the AST, which is more efficient in decode time and
space.
R=bradnelson@chromium.org,rossberg@chromium.org,binji@chromium.org
BUG=chromium:575167
LOG=Y
Review-Url: https://codereview.chromium.org/1830663002
Cr-Commit-Position: refs/heads/master@{#35896}
This patch provides a new implementation of popcnt and ctz in the case
where the platform does not provide these instructions. Instead of
building a TF graph which implements it we now call a C function.
Additionally I turned on additional tests in test-run-wasm-64.cc
R=titzer@chromium.org
Review URL: https://codereview.chromium.org/1857363003
Cr-Commit-Position: refs/heads/master@{#35685}
Int64Mul is lowered to a new turbofan operator, Int32MulPair. The new
operator takes 4 inputs an generates 2 outputs. The inputs are the low
word of the left input, high word of the left input, the low word of the
right input, and high word of the right input. The ouputs are the low
and high word of the result of the multiplication.
R=titzer@chromium.org, v8-arm-ports@googlegroups.com
Review URL: https://codereview.chromium.org/1807273002
Cr-Commit-Position: refs/heads/master@{#35131}
The new implementation deals with cycles in the TF graph in two steps:
1) The lowering of phis is delayed to avoid cyclic dependencies.
2) The replacement nodes of phis are created already when the phi is
pushed onto the stack so that other nodes can use these replacements
for their lowering.
R=titzer@chromium.org
Review URL: https://codereview.chromium.org/1844553002
Cr-Commit-Position: refs/heads/master@{#35126}
The CL #34701 (https://codereview.chromium.org/1779123002/) added the Run_WasmF32SConvertI64/Run_WasmF64SConvertI64 test cases and X87 failed at them.
The reason is same as the CL #33630 (Issue 1649323002: X87: Change the test case for X87 RunRoundInt32ToFloat32), please refer: https://codereview.chromium.org/1649323002.
Here is the key comments from CL #33630:
Some new test cases use CheckFloatEq(...) and CheckDoubleEq(...) function for result check. When GCC compiling the CheckFloatEq() and CheckDoubleEq() function,
those inlined functions has different behavior comparing with GCC ia32 build and x87 build.
The major difference is sse float register still has single precision rounding semantic. While X87 register has no such rounding precsion semantic when directly use register value.
The V8 turbofan JITTed has exactly same result in both X87 and IA32 port.
For CHECK_EQ(a, b) function, if a and b are double or float, it will has similar behaviors like CheckFloatEq(...) and CheckDoubleEq(...) function when compiled by GCC and causes the test case fail.
So we add the following sentence to do type case to keep the same precision for Run_WasmF32SConvertI64/Run_WasmF64SConvertI64. Such as: volatile double expect = static_cast<float>(*i).
ahaas put those codes in CHECK_FLOAT_EQ and CHECK_DOUBLE_EQ macros in CL #34534 (https://codereview.chromium.org/1773513002 ).
So this CL replaced the CHECK_EQ in Run_WasmF32SConvertI64/Run_WasmF64SConvertI64 to CHECK_FLOAT_EQ/CHECK_DOUBLE_EQ for x87 can pass Run_WasmF32SConvertI64/Run_WasmF64SConvertI64 tests.
BUG=
Review URL: https://codereview.chromium.org/1784813004
Cr-Commit-Position: refs/heads/master@{#34813}
Int64Sub is lowered to a new turbofan operator, Int32SubPair. The new
operator takes 4 inputs an generates 2 outputs. The inputs are the low
word of the left input, high word of the left input, the low word of the
right input, and high word of the right input. The ouputs are the low
and high word of the result of the subtraction.
The implementation is very similar to the implementation of Int64Add.
@v8-arm-ports: please take a careful look at the implementation of sbc
in the simulator.
R=titzer@chromium.org, v8-arm-ports@googlegroups.com
Review URL: https://codereview.chromium.org/1778893005
Cr-Commit-Position: refs/heads/master@{#34808}
Word64Popcnt is lowered to Word32Popcnt(low-word) + Word32Popcnt(high_word).
Since the optional Word64Popcnt operator does not exist on 32 bit platforms,
I introduced a new operator "Word64PopcntPlaceholder" which is generated
in the WasmCompiler and then lowered in the Int64Lowering.
R=titzer@chromium.org
Review URL: https://codereview.chromium.org/1803453003
Cr-Commit-Position: refs/heads/master@{#34777}
On 32-bit systems these instructions are compiled to calls to
C functions. The TF node for the function call is already generated in
the wasm compiler, the lowering of the I64 parameters is done in the
Int64Lowering. We use the return value of the C function to determine
whether the calculation should trap or not.
R=titzer@chromium.org
Review URL: https://codereview.chromium.org/1804513002
Cr-Commit-Position: refs/heads/master@{#34768}
Int64Add is lowered to a new turbofan operator, Int32AddPair. The new
operator takes 4 inputs an generates 2 outputs. The inputs are the low
word of the left input, high word of the left input, the low word of the
right input, and high word of the right input. The ouputs are the low
and high word of the result of the addition.
R=titzer@chromium.org, v8-arm-ports@googlegroups.com
Review URL: https://codereview.chromium.org/1778493004
Cr-Commit-Position: refs/heads/master@{#34747}
Move all tests that use i64 values into test-run-wasm-64.cc. Introduce
macros that enable tests as they are implemented on 32 bit platforms.
R=ahaas@chromium.org
BUG=
Review URL: https://codereview.chromium.org/1784343004
Cr-Commit-Position: refs/heads/master@{#34742}
On 32-bit systems I64XConvertFXX instructions are compiled to calls to
C functions. The TF node for the function call is already generated in
the wasm compiler, the lowering of the I64 parameter is done in the
Int64Lowering. We use the return value of the C function to determine
whether the conversion should trap or not.
R=titzer@chromium.org
Review URL: https://codereview.chromium.org/1775903002
Cr-Commit-Position: refs/heads/master@{#34738}
Local declarations were previously encoded as an optional set of
4 uint16 values as part of the function declaration. This CL
implements the current design of moving these declarations to
a list of pairs of (type, count) that is part of the body.
R=bradnelson@chromium.org,binji@chromium.org
BUG=
Review URL: https://codereview.chromium.org/1763433002
Cr-Commit-Position: refs/heads/master@{#34564}
I64Shl is lowered to a new turbofan operator, WasmWord64Shl. The new
operator takes 3 inputs, the low-word input, the high-word input, and
the shift, and produces 2 output, the low-word output and the high-word
output.
At the moment I implemented the lowering only for ia32, but I think the
CL is already big enough. I will add the other platforms in separate
CLs.
R=titzer@chromium.org
Review URL: https://codereview.chromium.org/1756863002
Cr-Commit-Position: refs/heads/master@{#34546}
On 32-bit systems FXXXConvertI64 instructions are compiled to calls to
C functions. The TF node for the function call is already generated in
the wasm compiler, the lowering of the I64 parameter is done in the
Int64Lowering.
R=titzer@chromium.org, yangguo@chromium.org
Review URL: https://codereview.chromium.org/1738623003
Cr-Commit-Position: refs/heads/master@{#34487}
