This patch updates internal data structures used by V8 to support
multiple indirect function tables (WebAssembly/design#682). But, since
this feature is post-MVP, the functionality is not directly exposed and
parsing/generation of WebAssembly is left unchanged. Nevertheless, it
is being used in an experiment to implement fine-grained control flow
integrity based on C/C++ types.
BUG=
Review-Url: https://codereview.chromium.org/2174123002
Cr-Commit-Position: refs/heads/master@{#38110}
When reading malformed input, the length of variable-length types can be very large. Computing operand length with this and adding it to PC will overflow and screw up decode.
This patch switches to unsigned int for arity and lengths, terminates loop analysis on error, adds overflow checking to BranchTableOperand, and adds a unit test.
Review-Url: https://codereview.chromium.org/2052623003
Cr-Commit-Position: refs/heads/master@{#37301}
Implements:
- WebAssembly object,
- WebAssembly.Module constructor,
- WebAssembly.Instance constructor,
- WebAssembly.compile async method,
- and Module and Instance instance objects.
Also, changes ErrorThrower to support capturing errors in a promise reject.
Since we cannot yet compile without fixing the Wasm memory, and cannot validate a module without compiling, the Module constructor and compile method don't do anything yet but checking that their argument is a suitable BufferSource. Instead of a compiled module, the hidden state of a Module object currently is just that buffer.
BUG=
Review-Url: https://codereview.chromium.org/2084573002
Cr-Commit-Position: refs/heads/master@{#37143}
Compilation of wasm functions happens before instantiation. Imports are linked afterwards, at instantiation time. Globals and memory are also
allocated and then tied in via relocation at instantiation time.
This paves the way for implementing Wasm.compile, a prerequisite to
offering the compiled code serialization feature.
Currently, the WasmModule::Compile method just returns a fixed array
containing the code objects. More appropriate modeling of the compiled module to come.
Opportunistically centralized the logic on how to update memory
references, size, and globals, since that logic is the exact same on each
architecture, except for the actual storing of values back in the
instruction stream.
BUG=v8:5072
Review-Url: https://codereview.chromium.org/2056633002
Cr-Commit-Position: refs/heads/master@{#37086}
The modifications were necessary to properly represent asm types:
1) fround is no longer an overloaded function.
2) the constructor for MinMaxTypes now takes a return type.
3) Adds pseudo-types for representing the Load/Store types for fp heap views.
BUG=
Review-Url: https://codereview.chromium.org/2069443002
Cr-Commit-Position: refs/heads/master@{#36980}
This CL introduces the new type system for the ASM
type-checker/validator.
BUG=
Review-Url: https://codereview.chromium.org/2045703007
Cr-Commit-Position: refs/heads/master@{#36942}
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}
Moved globals offsets calculation to the wasm module decoder, since
this is a property of the module, not of each instance.
Qualified as "const" references to WasmModule outside of the decoder
and some test situations.
BUG=
Review-Url: https://codereview.chromium.org/2005933003
Cr-Commit-Position: refs/heads/master@{#36484}
This is a first step to removing the support for the OldFunctions
section altogether, which will greatly simplify the encoder and remove
the need to do local variable remapping in asm->wasm.
R=bradnelson@chromium.org,aseemgarg@chromium.org
BUG=
Review-Url: https://codereview.chromium.org/1974933002
Cr-Commit-Position: refs/heads/master@{#36228}
This catches malformed code like the following example:
<expr>
<block begin>
<expr>
<binop>
<end>
Which is illegal because the inputs to the binop cross the block boundary.
R=rossberg@chromium.org,ahaas@chromium.org
BUG=
Review-Url: https://codereview.chromium.org/1961853002
Cr-Commit-Position: refs/heads/master@{#36103}
[wasm] Binary 11: Swap the order of section name / section length.
[wasm] Binary 11: Shorter section names.
[wasm] Binary 11: Add a prefix for function type declarations.
[wasm] Binary 11: Function types encoded as pcount, p*, rcount, r*
[wasm] Fix numeric names for functions.
R=rossberg@chromium.org,jfb@chromium.org,ahaas@chromium.org
BUG=chromium:575167
LOG=Y
Review-Url: https://codereview.chromium.org/1896863003
Cr-Commit-Position: refs/heads/master@{#35897}
[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 change implements switch as a balanced if/else tree or break table or
hybrid. A lot of asm.js modules are expected to extensively use switch
alongside function tables that can benefit from a better implementation.
BUG=v8:4203
TEST=mjsunit/asm-wasm
R=titzer@chromium.org,bradnelson@chromium.org,ahaas@chromium.org
LOG=N
Review URL: https://codereview.chromium.org/1838973002
Cr-Commit-Position: refs/heads/master@{#35455}
We expect that the majority of malloc'd memory held by V8 is allocated
in Zone objects. Introduce an Allocator class that is used by Zones to
manage memory, and allows for querying the current usage.
BUG=none
R=titzer@chromium.org,bmeurer@chromium.org,jarin@chromium.org
LOG=n
TBR=rossberg@chromium.org
Review URL: https://codereview.chromium.org/1847543002
Cr-Commit-Position: refs/heads/master@{#35196}
This CL modifies the following to be LEB128:
* Function table indices
* Import table signature indices
* Export table function indices
* Function signature param count
* br/br_if break depth
* br_table target count
* block/loop expression count
Still to do:
* Import/export names (LEB128 count + inline data)
* Data segments (LEB128 offset + size + inline data)
* Function header stuff (should seperate into function sig and body sections)
* Memory access alignment + offset (still discussing)
BUG=
R=titzer@chromium.org
Review URL: https://codereview.chromium.org/1775873002
Cr-Commit-Position: refs/heads/master@{#34603}
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}