pub trait FuncEnvironment: TargetEnvironment {
Show 37 methods fn make_global(
        &mut self,
        func: &mut Function,
        index: GlobalIndex
    ) -> WasmResult<GlobalVariable>;
fn make_heap(
        &mut self,
        func: &mut Function,
        index: MemoryIndex
    ) -> WasmResult<Heap>;
fn make_table(
        &mut self,
        func: &mut Function,
        index: TableIndex
    ) -> WasmResult<Table>;
fn make_indirect_sig(
        &mut self,
        func: &mut Function,
        index: TypeIndex
    ) -> WasmResult<SigRef>;
fn make_direct_func(
        &mut self,
        func: &mut Function,
        index: FuncIndex
    ) -> WasmResult<FuncRef>;
fn translate_call_indirect(
        &mut self,
        builder: &mut FunctionBuilder<'_>,
        table_index: TableIndex,
        table: Table,
        sig_index: TypeIndex,
        sig_ref: SigRef,
        callee: Value,
        call_args: &[Value]
    ) -> WasmResult<Inst>;
fn translate_memory_grow(
        &mut self,
        pos: FuncCursor<'_>,
        index: MemoryIndex,
        heap: Heap,
        val: Value
    ) -> WasmResult<Value>;
fn translate_memory_size(
        &mut self,
        pos: FuncCursor<'_>,
        index: MemoryIndex,
        heap: Heap
    ) -> WasmResult<Value>;
fn translate_memory_copy(
        &mut self,
        pos: FuncCursor<'_>,
        src_index: MemoryIndex,
        src_heap: Heap,
        dst_index: MemoryIndex,
        dst_heap: Heap,
        dst: Value,
        src: Value,
        len: Value
    ) -> WasmResult<()>;
fn translate_memory_fill(
        &mut self,
        pos: FuncCursor<'_>,
        index: MemoryIndex,
        heap: Heap,
        dst: Value,
        val: Value,
        len: Value
    ) -> WasmResult<()>;
fn translate_memory_init(
        &mut self,
        pos: FuncCursor<'_>,
        index: MemoryIndex,
        heap: Heap,
        seg_index: u32,
        dst: Value,
        src: Value,
        len: Value
    ) -> WasmResult<()>;
fn translate_data_drop(
        &mut self,
        pos: FuncCursor<'_>,
        seg_index: u32
    ) -> WasmResult<()>;
fn translate_table_size(
        &mut self,
        pos: FuncCursor<'_>,
        index: TableIndex,
        table: Table
    ) -> WasmResult<Value>;
fn translate_table_grow(
        &mut self,
        pos: FuncCursor<'_>,
        table_index: TableIndex,
        table: Table,
        delta: Value,
        init_value: Value
    ) -> WasmResult<Value>;
fn translate_table_get(
        &mut self,
        builder: &mut FunctionBuilder<'_>,
        table_index: TableIndex,
        table: Table,
        index: Value
    ) -> WasmResult<Value>;
fn translate_table_set(
        &mut self,
        builder: &mut FunctionBuilder<'_>,
        table_index: TableIndex,
        table: Table,
        value: Value,
        index: Value
    ) -> WasmResult<()>;
fn translate_table_copy(
        &mut self,
        pos: FuncCursor<'_>,
        dst_table_index: TableIndex,
        dst_table: Table,
        src_table_index: TableIndex,
        src_table: Table,
        dst: Value,
        src: Value,
        len: Value
    ) -> WasmResult<()>;
fn translate_table_fill(
        &mut self,
        pos: FuncCursor<'_>,
        table_index: TableIndex,
        dst: Value,
        val: Value,
        len: Value
    ) -> WasmResult<()>;
fn translate_table_init(
        &mut self,
        pos: FuncCursor<'_>,
        seg_index: u32,
        table_index: TableIndex,
        table: Table,
        dst: Value,
        src: Value,
        len: Value
    ) -> WasmResult<()>;
fn translate_elem_drop(
        &mut self,
        pos: FuncCursor<'_>,
        seg_index: u32
    ) -> WasmResult<()>;
fn translate_ref_func(
        &mut self,
        pos: FuncCursor<'_>,
        func_index: FuncIndex
    ) -> WasmResult<Value>;
fn translate_custom_global_get(
        &mut self,
        pos: FuncCursor<'_>,
        global_index: GlobalIndex
    ) -> WasmResult<Value>;
fn translate_custom_global_set(
        &mut self,
        pos: FuncCursor<'_>,
        global_index: GlobalIndex,
        val: Value
    ) -> WasmResult<()>;
fn translate_atomic_wait(
        &mut self,
        pos: FuncCursor<'_>,
        index: MemoryIndex,
        heap: Heap,
        addr: Value,
        expected: Value,
        timeout: Value
    ) -> WasmResult<Value>;
fn translate_atomic_notify(
        &mut self,
        pos: FuncCursor<'_>,
        index: MemoryIndex,
        heap: Heap,
        addr: Value,
        count: Value
    ) -> WasmResult<Value>;
fn unsigned_add_overflow_condition(&self) -> IntCC; fn is_wasm_parameter(&self, signature: &Signature, index: usize) -> bool { ... }
fn is_wasm_return(&self, signature: &Signature, index: usize) -> bool { ... }
fn after_locals(&mut self, num_locals_defined: usize) { ... }
fn translate_call(
        &mut self,
        pos: FuncCursor<'_>,
        _callee_index: FuncIndex,
        callee: FuncRef,
        call_args: &[Value]
    ) -> WasmResult<Inst> { ... }
fn translate_ref_null(
        &mut self,
        pos: FuncCursor<'_>,
        ty: WasmType
    ) -> WasmResult<Value> { ... }
fn translate_ref_is_null(
        &mut self,
        pos: FuncCursor<'_>,
        value: Value
    ) -> WasmResult<Value> { ... }
fn translate_loop_header(
        &mut self,
        _builder: &mut FunctionBuilder<'_>
    ) -> WasmResult<()> { ... }
fn before_translate_operator(
        &mut self,
        _op: &Operator<'_>,
        _builder: &mut FunctionBuilder<'_>,
        _state: &FuncTranslationState
    ) -> WasmResult<()> { ... }
fn after_translate_operator(
        &mut self,
        _op: &Operator<'_>,
        _builder: &mut FunctionBuilder<'_>,
        _state: &FuncTranslationState
    ) -> WasmResult<()> { ... }
fn before_translate_function(
        &mut self,
        _builder: &mut FunctionBuilder<'_>,
        _state: &FuncTranslationState
    ) -> WasmResult<()> { ... }
fn after_translate_function(
        &mut self,
        _builder: &mut FunctionBuilder<'_>,
        _state: &FuncTranslationState
    ) -> WasmResult<()> { ... }
}
Expand description

Environment affecting the translation of a single WebAssembly function.

A FuncEnvironment trait object is required to translate a WebAssembly function to Cranelift IR. The function environment provides information about the WebAssembly module as well as the runtime environment.

Required methods

Set up the necessary preamble definitions in func to access the global variable identified by index.

The index space covers both imported globals and globals defined by the module.

Return the global variable reference that should be used to access the global and the WebAssembly type of the global.

Set up the necessary preamble definitions in func to access the linear memory identified by index.

The index space covers both imported and locally declared memories.

Set up the necessary preamble definitions in func to access the table identified by index.

The index space covers both imported and locally declared tables.

Set up a signature definition in the preamble of func that can be used for an indirect call with signature index.

The signature may contain additional arguments needed for an indirect call, but the arguments marked as ArgumentPurpose::Normal must correspond to the WebAssembly signature arguments.

The signature will only be used for indirect calls, even if the module has direct function calls with the same WebAssembly type.

Set up an external function definition in the preamble of func that can be used to directly call the function index.

The index space covers both imported functions and functions defined in the current module.

The function’s signature may contain additional arguments needed for a direct call, but the arguments marked as ArgumentPurpose::Normal must correspond to the WebAssembly signature arguments.

The function’s signature will only be used for direct calls, even if the module has indirect calls with the same WebAssembly type.

Translate a call_indirect WebAssembly instruction at pos.

Insert instructions at pos for an indirect call to the function callee in the table table_index with WebAssembly signature sig_index. The callee value will have type i32.

The signature sig_ref was previously created by make_indirect_sig().

Return the call instruction whose results are the WebAssembly return values.

Translate a memory.grow WebAssembly instruction.

The index provided identifies the linear memory to grow, and heap is the heap reference returned by make_heap for the same index.

The val value is the requested memory size in pages.

Returns the old size (in pages) of the memory.

Translates a memory.size WebAssembly instruction.

The index provided identifies the linear memory to query, and heap is the heap reference returned by make_heap for the same index.

Returns the size in pages of the memory.

Translate a memory.copy WebAssembly instruction.

The index provided identifies the linear memory to query, and heap is the heap reference returned by make_heap for the same index.

Translate a memory.fill WebAssembly instruction.

The index provided identifies the linear memory to query, and heap is the heap reference returned by make_heap for the same index.

Translate a memory.init WebAssembly instruction.

The index provided identifies the linear memory to query, and heap is the heap reference returned by make_heap for the same index. seg_index is the index of the segment to copy from.

Translate a data.drop WebAssembly instruction.

Translate a table.size WebAssembly instruction.

Translate a table.grow WebAssembly instruction.

Translate a table.get WebAssembly instruction.

Translate a table.set WebAssembly instruction.

Translate a table.copy WebAssembly instruction.

Translate a table.fill WebAssembly instruction.

Translate a table.init WebAssembly instruction.

Translate a elem.drop WebAssembly instruction.

Translate a ref.func WebAssembly instruction.

Translate a global.get WebAssembly instruction at pos for a global that is custom.

Translate a global.set WebAssembly instruction at pos for a global that is custom.

Translate an i32.atomic.wait or i64.atomic.wait WebAssembly instruction. The index provided identifies the linear memory containing the value to wait on, and heap is the heap reference returned by make_heap for the same index. Whether the waited-on value is 32- or 64-bit can be determined by examining the type of expected, which must be only I32 or I64.

Note that the addr here is the host linear memory address rather than a relative wasm linear memory address. The type of this value is the same as the host’s pointer.

Returns an i32, which is negative if the helper call failed.

Translate an atomic.notify WebAssembly instruction. The index provided identifies the linear memory containing the value to wait on, and heap is the heap reference returned by make_heap for the same index.

Note that the addr here is the host linear memory address rather than a relative wasm linear memory address. The type of this value is the same as the host’s pointer.

Returns an i64, which is negative if the helper call failed.

Returns the target ISA’s condition to check for unsigned addition overflowing.

Provided methods

Is the given parameter of the given function a wasm-level parameter, as opposed to a hidden parameter added for use by the implementation?

Is the given return of the given function a wasm-level parameter, as opposed to a hidden parameter added for use by the implementation?

Called after the locals for a function have been parsed, and the number of variables defined by this function is provided.

Translate a call WebAssembly instruction at pos.

Insert instructions at pos for a direct call to the function callee_index.

The function reference callee was previously created by make_direct_func().

Return the call instruction whose results are the WebAssembly return values.

Translate a ref.null T WebAssembly instruction.

By default, translates into a null reference type.

Override this if you don’t use Cranelift reference types for all Wasm reference types (e.g. you use a raw pointer for funcrefs) or if the null sentinel is not a null reference type pointer for your type. If you override this method, then you should also override translate_ref_is_null as well.

Translate a ref.is_null WebAssembly instruction.

By default, assumes that value is a Cranelift reference type, and that a null Cranelift reference type is the null value for all Wasm reference types.

If you override this method, you probably also want to override translate_ref_null as well.

Emit code at the beginning of every wasm loop.

This can be used to insert explicit interrupt or safepoint checking at the beginnings of loops.

Optional callback for the FunctionEnvironment performing this translation to maintain internal state or prepare custom state for the operator to translate

Optional callback for the FunctionEnvironment performing this translation to maintain internal state or finalize custom state for the operator that was translated

Optional callback for the FunctionEnvironment performing this translation to perform work before the function body is translated.

Optional callback for the FunctionEnvironment performing this translation to perform work after the function body is translated.

Implementors