binaryen.js API

Overview

binaryen.js is a port of Binaryen to the Web, allowing you to generate WebAssembly using a JavaScript API. To get a feel for the API, see the hello world test, and other tests in that directory for more examples.

The API is documented in the rest of this document.

Types

none: Type
The none type, e.g., void.
i32: Type
32-bit integer type.
i64: Type
64-bit integer type.
f32: Type
32-bit float type.
f64: Type
64-bit float (double) type.
auto: Type
Special type used in Module#block exclusively. Lets the API figure out a block's result type automatically.
unreachable: Type
Special type indicating unreachable code when obtaining information about an expression.

Module construction

new Module(): Module
Constructs a new module.
parseText(text: string): Module
Creates a module from Binaryen's s-expression text format (not official stack-style text format).
readBinary(data: Uint8Array): Module
Creates a module from binary data.
wrapModule(ptr: number): Module
Wraps a module pointer as used with the underlying C-API as a JS module object.

Module manipulation

Module#addFunctionType(name: string, resultType: Type, paramTypes: Type[]): Signature
Adds a new function type.
Module#getFunctionTypeBySignature(resultType: Type, paramTypes: Type[]): Signature
Gets an existing function type by its parametric signature. Returns 0 if there is no such function type.
Module#removeFunctionType(name: string): void
Removes a function type.
Module#addFunction(name: string, functionType: Signature, varTypes: Type[], body: Expression): Function
Adds a function. varTypes indicate additional locals, in the given order.
Module#getFunction(name: string): Function
Gets a function, by name,
Module#removeFunction(name: string): void
Removes a function, by name.
Module#addFunctionImport(internalName: string, externalModuleName: string, externalBaseName: string, functionType: Signature): Import
Adds a function import.
Module#addTableImport(internalName: string, externalModuleName: string, externalBaseName: string): Import
Adds a table import. There's just one table for now, using name "0".
Module#addMemoryImport(internalName: string, externalModuleName: string, externalBaseName: string): Import
Adds a memory import. There's just one memory for now, using name "0".
Module#addGlobalImport(internalName: string, externalModuleName: string, externalBaseName: string, globalType: Type): Import
Adds a global variable import. Imported globals must be immutable.
Module#addFunctionExport(internalName: string, externalName: string): Export
Adds a function export.
Module#addTableExport(internalName: string, externalName: string): Export
Adds a table export. There's just one table for now, using name "0".
Module#addMemoryExport(internalName: string, externalName: string): Export
Adds a memory export. There's just one memory for now, using name "0".
Module#addGlobalExport(internalName: string, externalName: string): Export
Adds a global variable export. Exported globals must be immutable.
Module#addGlobal(name: string, type: Type, mutable: number, value: Expression): Global
Adds a global instance variable.
Module#removeExport(externalName: string): void
Removes an export, by external name.
Module#setFunctionTable(initial: number, maximum: number, funcs: string[]): void
Sets the contents of the function table. There's just one table for now, using name "0".
Module#setMemory(initial: number, maximum: number, exportName: string | null, segments: MemorySegment[]): void
Sets the memory. There's just one memory for now, using name "0". Providing exportName also creates a memory export.
Module#setStart(start: Function): void
Sets the start function.
Module#autoDrop(): void
Enables automatic insertion of drop operations where needed. Lets you not worry about dropping when creating your code.
getFunctionTypeInfo(ftype: FunctionType: FunctionTypeInfo
Obtains information about a function type.
- FunctionTypeInfo#name: string | null
- FunctionTypeInfo#params: Type[]
- FunctionTypeInfo#result: Type
getFunctionInfo(ftype: Function: FunctionInfo
Obtains information about a function.
- FunctionInfo#name: string
- FunctionInfo#module: string | null (if imported)
- FunctionInfo#base: string | null (if imported)
- FunctionInfo#type: FunctionType
- FunctionInfo#params: Type[]
- FunctionInfo#result: Type
- FunctionInfo#vars: Type
- FunctionInfo#body: Expression
getGlobalInfo(global: Global): GlobalInfo
Obtains information about a global.
- GlobalInfo#name: string
- GlobalInfo#module: string | null (if imported)
- GlobalInfo#base: string | null (if imported)
- GlobalInfo#type: Type
getExportInfo(export_: Export): ExportInfo
Obtains information about an export.
ExportInfo#kind: ExternalKind
ExportInfo#name: string
ExportInfo#value: string

Possible ExternalKind values are:

ExternalFunction: ExternalKind
ExternalTable: ExternalKind
ExternalMemory: ExternalKind
ExternalGlobal: ExternalKind

Module validation

Module#validate(): boolean
Validates the module. Returns true if valid, otherwise prints validation errors and returns false.

Module optimization

Module#optimize(): void
Optimizes the module using the default optimization passes.
Module#optimizeFunction(func: Function | string): void
Optimizes a single function using the default optimization passes.
Module#runPasses(passes: string[]): void
Runs the specified passes on the module.
Module#runPassesOnFunction(func: Function | string, passes: string[]): void
Runs the specified passes on a single function.
getOptimizeLevel(): number
Gets the currently set optimize level. 0, 1, 2 correspond to -O0, -O1, -O2 (default), etc.
setOptimizeLevel(level: number): void
Sets the optimization level to use. 0, 1, 2 correspond to -O0, -O1, -O2 (default), etc.
getShrinkLevel(): number
Gets the currently set shrink level. 0, 1, 2 correspond to -O0, -Os (default), -Oz.
setShrinkLevel(level: number): void
Sets the shrink level to use. 0, 1, 2 correspond to -O0, -Os (default), -Oz.
getDebugInfo(): boolean
Gets whether generating debug information is currently enabled or not.
setDebugInfo(on: boolean): void
Enables or disables debug information in emitted binaries.

Module creation

Module#emitBinary(): Uint8Array
Returns the module in binary format.
Module#emitBinary(sourceMapUrl: string | null): BinaryWithSourceMap
Returns the module in binary format with its source map. If sourceMapUrl is null, source map generation is skipped.
- BinaryWithSourceMap#binary: Uint8Array
- BinaryWithSourceMap#sourceMap: string | null
Module#emitText(): string
Returns the module in Binaryen's s-expression text format (not official stack-style text format).
Module#emitAsmjs(): string
Returns the asm.js representation of the module.
Module#dispose(): void
Releases the resources held by the module once it isn't needed anymore.

Expression construction

Control flow

Module#block(label: string | null, children: Expression[], resultType?: Type): Expression
Creates a block. resultType defaults to none.
Module#if(condition: Expression, ifTrue: Expression, ifFalse?: Expression): Expression
Creates an if or if/else combination.
Module#loop(label: string | null, body: Expression): Expression
Creates a loop.
Module#break(label: string, condition?: Expression, value?: Expression): Expression
Creates a break (br) to a label.
Module#switch(labels: string[], defaultLabel: string, condition: Expression, value?: Expression): Expression
Creates a switch (br_table).
Module#nop(): Expression
Creates a no-operation (nop) instruction.
Module#return(value?: Expression): Expression Creates a return.
Module#unreachable(): Expression
Creates an unreachable instruction that will always trap.
Module#drop(value: Expression): Expression
Creates a drop of a value.
Module#select(condition: Expression, ifTrue: Expression, ifFalse: Expression): Expression
Creates a select of one of two values.

Constants

Module#i32.const(value: number): Expression

Module#i64.const(low: number, high: number): Expression

Module#f32.const(value: number): Expression
Module#f32.const_bits(value: number): Expression

Module#f64.const(value: number): Expression
Module#f64.const_bits(low: number, high: number): Expression

Variable accesses

Module#local.get(index: number, type: Type): Expression
Creates a get for the local at the specified index. Note that we must specify the type here as we may not have created the local being called yet.
Module#local.set(index: number, value: Expression): Expression
Creates a set for the local at the specified index.
Module#local.tee(index: number, value: Expression): Expression
Creates a tee for the local at the specified index. A tee differs from a set in that the value remains on the stack.
Module#global.get(name: string, type: Type): Expression
Creates a get for the global with the specified name. Note that we must specify the type here as we may not have created the global being called yet.
Module#global.set(name: string, value: Expression): Expression
Creates a set for the global with the specified name.

Integer operations

Module#i32.clz(value: Expression): Expression
Module#i32.ctz(value: Expression): Expression
Module#i32.popcnt(value: Expression): Expression
Module#i32.eqz(value: Expression): Expression
Module#i32.add(left: Expression, right: Expression): Expression
Module#i32.sub(left: Expression, right: Expression): Expression
Module#i32.mul(left: Expression, right: Expression): Expression
Module#i32.div_s(left: Expression, right: Expression): Expression
Module#i32.div_u(left: Expression, right: Expression): Expression
Module#i32.rem_s(left: Expression, right: Expression): Expression
Module#i32.rem_u(left: Expression, right: Expression): Expression
Module#i32.and(left: Expression, right: Expression): Expression
Module#i32.or(left: Expression, right: Expression): Expression
Module#i32.xor(left: Expression, right: Expression): Expression
Module#i32.shl(left: Expression, right: Expression): Expression
Module#i32.shr_u(left: Expression, right: Expression): Expression
Module#i32.shr_s(left: Expression, right: Expression): Expression
Module#i32.rotl(left: Expression, right: Expression): Expression
Module#i32.rotr(left: Expression, right: Expression): Expression
Module#i32.eq(left: Expression, right: Expression): Expression
Module#i32.ne(left: Expression, right: Expression): Expression
Module#i32.lt_s(left: Expression, right: Expression): Expression
Module#i32.lt_u(left: Expression, right: Expression): Expression
Module#i32.le_s(left: Expression, right: Expression): Expression
Module#i32.le_u(left: Expression, right: Expression): Expression
Module#i32.gt_s(left: Expression, right: Expression): Expression
Module#i32.gt_u(left: Expression, right: Expression): Expression
Module#i32.ge_s(left: Expression, right: Expression): Expression
Module#i32.ge_u(left: Expression, right: Expression): Expression

Module#i64.clz(value: Expression): Expression
Module#i64.ctz(value: Expression): Expression
Module#i64.popcnt(value: Expression): Expression
Module#i64.eqz(value: Expression): Expression
Module#i64.add(left: Expression, right: Expression): Expression
Module#i64.sub(left: Expression, right: Expression): Expression
Module#i64.mul(left: Expression, right: Expression): Expression
Module#i64.div_s(left: Expression, right: Expression): Expression
Module#i64.div_u(left: Expression, right: Expression): Expression
Module#i64.rem_s(left: Expression, right: Expression): Expression
Module#i64.rem_u(left: Expression, right: Expression): Expression
Module#i64.and(left: Expression, right: Expression): Expression
Module#i64.or(left: Expression, right: Expression): Expression
Module#i64.xor(left: Expression, right: Expression): Expression
Module#i64.shl(left: Expression, right: Expression): Expression
Module#i64.shr_u(left: Expression, right: Expression): Expression
Module#i64.shr_s(left: Expression, right: Expression): Expression
Module#i64.rotl(left: Expression, right: Expression): Expression
Module#i64.rotr(left: Expression, right: Expression): Expression
Module#i64.eq(left: Expression, right: Expression): Expression
Module#i64.ne(left: Expression, right: Expression): Expression
Module#i64.lt_s(left: Expression, right: Expression): Expression
Module#i64.lt_u(left: Expression, right: Expression): Expression
Module#i64.le_s(left: Expression, right: Expression): Expression
Module#i64.le_u(left: Expression, right: Expression): Expression
Module#i64.gt_s(left: Expression, right: Expression): Expression
Module#i64.gt_u(left: Expression, right: Expression): Expression
Module#i64.ge_s(left: Expression, right: Expression): Expression
Module#i64.ge_u(left: Expression, right: Expression): Expression

Floating point operations

Module#f32.neg(value: Expression): Expression
Module#f32.abs(value: Expression): Expression
Module#f32.ceil(value: Expression): Expression
Module#f32.floor(value: Expression): Expression
Module#f32.trunc(value: Expression): Expression
Module#f32.nearest(value: Expression): Expression
Module#f32.sqrt(value: Expression): Expression
Module#f32.add(left: Expression, right: Expression): Expression
Module#f32.sub(left: Expression, right: Expression): Expression
Module#f32.mul(left: Expression, right: Expression): Expression
Module#f32.div(left: Expression, right: Expression): Expression
Module#f32.copysign(left: Expression, right: Expression): Expression
Module#f32.min(left: Expression, right: Expression): Expression
Module#f32.max(left: Expression, right: Expression): Expression
Module#f32.eq(left: Expression, right: Expression): Expression
Module#f32.ne(left: Expression, right: Expression): Expression
Module#f32.lt(left: Expression, right: Expression): Expression
Module#f32.le(left: Expression, right: Expression): Expression
Module#f32.gt(left: Expression, right: Expression): Expression
Module#f32.ge(left: Expression, right: Expression): Expression

Module#f64.neg(value: Expression): Expression
Module#f64.abs(value: Expression): Expression
Module#f64.ceil(value: Expression): Expression
Module#f64.floor(value: Expression): Expression
Module#f64.trunc(value: Expression): Expression
Module#f64.nearest(value: Expression): Expression
Module#f64.sqrt(value: Expression): Expression
Module#f64.add(left: Expression, right: Expression): Expression
Module#f64.sub(left: Expression, right: Expression): Expression
Module#f64.mul(left: Expression, right: Expression): Expression
Module#f64.div(left: Expression, right: Expression): Expression
Module#f64.copysign(left: Expression, right: Expression): Expression
Module#f64.min(left: Expression, right: Expression): Expression
Module#f64.max(left: Expression, right: Expression): Expression
Module#f64.eq(left: Expression, right: Expression): Expression
Module#f64.ne(left: Expression, right: Expression): Expression
Module#f64.lt(left: Expression, right: Expression): Expression
Module#f64.le(left: Expression, right: Expression): Expression
Module#f64.gt(left: Expression, right: Expression): Expression
Module#f64.ge(left: Expression, right: Expression): Expression

Datatype conversions

Module#i32.trunc_s.f32(value: Expression): Expression
Module#i32.trunc_s.f64(value: Expression): Expression
Module#i32.trunc_u.f32(value: Expression): Expression
Module#i32.trunc_u.f64(value: Expression): Expression
Module#i32.reinterpret(value: Expression): Expression
Module#i32.wrap(value: Expression): Expression

Module#i64.trunc_s.f32(value: Expression): Expression
Module#i64.trunc_s.f64(value: Expression): Expression
Module#i64.trunc_u.f32(value: Expression): Expression
Module#i64.trunc_u.f64(value: Expression): Expression
Module#i64.reinterpret(value: Expression): Expression
Module#i64.extend_s(value: Expression): Expression
Module#i64.extend_u(value: Expression): Expression

Module#f32.reinterpret(value: Expression): Expression
Module#f32.convert_s.i32(value: Expression): Expression
Module#f32.convert_s.i64(value: Expression): Expression
Module#f32.convert_u.i32(value: Expression): Expression
Module#f32.convert_u.i64(value: Expression): Expression
Module#f32.demote(value: Expression): Expression

Module#f64.reinterpret(value: Expression): Expression
Module#f64.convert_s.i32(value: Expression): Expression
Module#f64.convert_s.i64(value: Expression): Expression
Module#f64.convert_u.i32(value: Expression): Expression
Module#f64.convert_u.i64(value: Expression): Expression
Module#f64.promote(value: Expression): Expression

Function calls

Module#call(name: string, operands: Expression[], returnType: Type): Expression
Creates a call to a function. Note that we must specify the return type here as we may not have created the function being called yet.
Module#call_indirect/callIndirect(target: Expression, operands: Expression[], returnType: Type): Expression
Similar to call, but calls indirectly, i.e., via a function pointer, so an expression replaces the name as the called value.

Linear memory accesses

Module#i32.load(offset: number, align: number, ptr: Expression): Expression
Module#i32.load8_s(offset: number, align: number, ptr: Expression): Expression
Module#i32.load8_u(offset: number, align: number, ptr: Expression): Expression
Module#i32.load16_s(offset: number, align: number, ptr: Expression): Expression
Module#i32.load16_u(offset: number, align: number, ptr: Expression): Expression
Module#i32.store(offset: number, align: number, ptr: Expression, value: Expression): Expression
Module#i32.store8(offset: number, align: number, ptr: Expression, value: Expression): Expression
Module#i32.store16(offset: number, align: number, ptr: Expression, value: Expression): Expression

Module#i64.load(offset: number, align: number, ptr: Expression): Expression
Module#i64.load8_s(offset: number, align: number, ptr: Expression): Expression
Module#i64.load8_u(offset: number, align: number, ptr: Expression): Expression
Module#i64.load16_s(offset: number, align: number, ptr: Expression): Expression
Module#i64.load16_u(offset: number, align: number, ptr: Expression): Expression
Module#i64.load32_s(offset: number, align: number, ptr: Expression): Expression
Module#i64.load32_u(offset: number, align: number, ptr: Expression): Expression
Module#i64.store(offset: number, align: number, ptr: Expression, value: Expression): Expression
Module#i64.store8(offset: number, align: number, ptr: Expression, value: Expression): Expression
Module#i64.store16(offset: number, align: number, ptr: Expression, value: Expression): Expression
Module#i64.store32(offset: number, align: number, ptr: Expression, value: Expression): Expression

Module#f32.load(offset: number, align: number, ptr: Expression): Expression
Module#f32.store(offset: number, align: number, ptr: Expression, value: Expression): Expression

Module#f64.load(offset: number, align: number, ptr: Expression): Expression
Module#f64.store(offset: number, align: number, ptr: Expression, value: Expression): Expression

Host operations

Module#current_memory/currentMemory(): Expression
Module#grow_memory/growMemory(value: number): Expression
Module#has_feature/hasFeature(name: string): Expression 🦄

Atomic memory accesses 🦄

Module#i32.atomic.load(offset: number, ptr: Expression): Expression
Module#i32.atomic.load8_u(offset: number, ptr: Expression): Expression
Module#i32.atomic.load16_u(offset: number, ptr: Expression): Expression
Module#i32.atomic.store(offset: number, ptr: Expression, value: Expression): Expression
Module#i32.atomic.store8(offset: number, ptr: Expression, value: Expression): Expression
Module#i32.atomic.store16(offset: number, ptr: Expression, value: Expression): Expression

Module#i64.atomic.load(offset: number, ptr: Expression): Expression
Module#i64.atomic.load8_u(offset: number, ptr: Expression): Expression
Module#i64.atomic.load16_u(offset: number, ptr: Expression): Expression
Module#i64.atomic.load32_u(offset: number, ptr: Expression): Expression
Module#i64.atomic.store(offset: number, ptr: Expression, value: Expression): Expression
Module#i64.atomic.store8(offset: number, ptr: Expression, value: Expression): Expression
Module#i64.atomic.store16(offset: number, ptr: Expression, value: Expression): Expression
Module#i64.atomic.store32(offset: number, ptr: Expression, value: Expression): Expression

Atomic read-modify-write operations 🦄

Module#i32.atomic.rmw.add(offset: number, ptr: Expression, value: Expression): Expression
Module#i32.atomic.rmw.sub(offset: number, ptr: Expression, value: Expression): Expression
Module#i32.atomic.rmw.and(offset: number, ptr: Expression, value: Expression): Expression
Module#i32.atomic.rmw.or(offset: number, ptr: Expression, value: Expression): Expression
Module#i32.atomic.rmw.xor(offset: number, ptr: Expression, value: Expression): Expression
Module#i32.atomic.rmw.xchg(offset: number, ptr: Expression, value: Expression): Expression
Module#i32.atomic.rmw.cmpxchg(offset: number, ptr: Expression, expected: Expression, replacement: Expression): Expression
Module#i32.atomic.rmw8_u.add(offset: number, ptr: Expression, value: Expression): Expression
Module#i32.atomic.rmw8_u.sub(offset: number, ptr: Expression, value: Expression): Expression
Module#i32.atomic.rmw8_u.and(offset: number, ptr: Expression, value: Expression): Expression
Module#i32.atomic.rmw8_u.or(offset: number, ptr: Expression, value: Expression): Expression
Module#i32.atomic.rmw8_u.xor(offset: number, ptr: Expression, value: Expression): Expression
Module#i32.atomic.rmw8_u.xchg(offset: number, ptr: Expression, value: Expression): Expression
Module#i32.atomic.rmw8_u.cmpxchg(offset: number, ptr: Expression, expected: Expression, replacement: Expression): Expression
Module#i32.atomic.rmw16_u.add(offset: number, ptr: Expression, value: Expression): Expression
Module#i32.atomic.rmw16_u.sub(offset: number, ptr: Expression, value: Expression): Expression
Module#i32.atomic.rmw16_u.and(offset: number, ptr: Expression, value: Expression): Expression
Module#i32.atomic.rmw16_u.or(offset: number, ptr: Expression, value: Expression): Expression
Module#i32.atomic.rmw16_u.xor(offset: number, ptr: Expression, value: Expression): Expression
Module#i32.atomic.rmw16_u.xchg(offset: number, ptr: Expression, value: Expression): Expression
Module#i32.atomic.rmw16_u.cmpxchg(offset: number, ptr: Expression, expected: Expression, replacement: Expression): Expression

Module#i64.atomic.rmw.add(offset: number, ptr: Expression, value: Expression): Expression
Module#i64.atomic.rmw.sub(offset: number, ptr: Expression, value: Expression): Expression
Module#i64.atomic.rmw.and(offset: number, ptr: Expression, value: Expression): Expression
Module#i64.atomic.rmw.or(offset: number, ptr: Expression, value: Expression): Expression
Module#i64.atomic.rmw.xor(offset: number, ptr: Expression, value: Expression): Expression
Module#i64.atomic.rmw.xchg(offset: number, ptr: Expression, value: Expression): Expression
Module#i64.atomic.rmw.cmpxchg(offset: number, ptr: Expression, expected: Expression, replacement: Expression): Expression
Module#i64.atomic.rmw8_u.add(offset: number, ptr: Expression, value: Expression): Expression
Module#i64.atomic.rmw8_u.sub(offset: number, ptr: Expression, value: Expression): Expression
Module#i64.atomic.rmw8_u.and(offset: number, ptr: Expression, value: Expression): Expression
Module#i64.atomic.rmw8_u.or(offset: number, ptr: Expression, value: Expression): Expression
Module#i64.atomic.rmw8_u.xor(offset: number, ptr: Expression, value: Expression): Expression
Module#i64.atomic.rmw8_u.xchg(offset: number, ptr: Expression, value: Expression): Expression
Module#i64.atomic.rmw8_u.cmpxchg(offset: number, ptr: Expression, expected: Expression, replacement: Expression): Expression
Module#i64.atomic.rmw16_u.add(offset: number, ptr: Expression, value: Expression): Expression
Module#i64.atomic.rmw16_u.sub(offset: number, ptr: Expression, value: Expression): Expression
Module#i64.atomic.rmw16_u.and(offset: number, ptr: Expression, value: Expression): Expression
Module#i64.atomic.rmw16_u.or(offset: number, ptr: Expression, value: Expression): Expression
Module#i64.atomic.rmw16_u.xor(offset: number, ptr: Expression, value: Expression): Expression
Module#i64.atomic.rmw16_u.xchg(offset: number, ptr: Expression, value: Expression): Expression
Module#i64.atomic.rmw16_u.cmpxchg(offset: number, ptr: Expression, expected: Expression, replacement: Expression): Expression
Module#i64.atomic.rmw32_u.add(offset: number, ptr: Expression, value: Expression): Expression
Module#i64.atomic.rmw32_u.sub(offset: number, ptr: Expression, value: Expression): Expression
Module#i64.atomic.rmw32_u.and(offset: number, ptr: Expression, value: Expression): Expression
Module#i64.atomic.rmw32_u.or(offset: number, ptr: Expression, value: Expression): Expression
Module#i64.atomic.rmw32_u.xor(offset: number, ptr: Expression, value: Expression): Expression
Module#i64.atomic.rmw32_u.xchg(offset: number, ptr: Expression, value: Expression): Expression
Module#i64.atomic.rmw32_u.cmpxchg(offset: number, ptr: Expression, expected: Expression, replacement: Expression): Expression

Atomic wait and wake operations 🦄

Module#i32.wait(ptr: Expression, expected: Expression, timeout: Expression): Expression
Module#i64.wait(ptr: Expression, expected: Expression, timeout: Expression): Expression
Module#wake(ptr: Expression, wakeCount: Expression): Expression

Sign extension operations 🦄

Module#i32.extend8_s(value: Expression): Expression
Module#i32.extend16_s(value: Expression): Expression

Module#i64.extend8_s(value: Expression): Expression
Module#i64.extend16_s(value: Expression): Expression
Module#i64.extend32_s(value: Expression): Expression

Expression manipulation

getExpressionId(expr: Expression): ExpressionId
Gets the id (kind) of the specified expression. Possible values are:
- InvalidId: ExpressionId
- BlockId: ExpressionId
- IfId: ExpressionId
- LoopId: ExpressionId
- BreakId: ExpressionId
- SwitchId: ExpressionId
- CallId: ExpressionId
- CallImportId: ExpressionId
- CallIndirectId: ExpressionId
- GetLocalId: ExpressionId
- SetLocalId: ExpressionId
- GetGlobalId: ExpressionId
- SetGlobalId: ExpressionId
- LoadId: ExpressionId
- StoreId: ExpressionId
- ConstId: ExpressionId
- UnaryId: ExpressionId
- BinaryId: ExpressionId
- SelectId: ExpressionId
- DropId: ExpressionId
- ReturnId: ExpressionId
- HostId: ExpressionId
- NopId: ExpressionId
- UnreachableId: ExpressionId
- AtomicCmpxchgId: ExpressionId
- AtomicRMWId: ExpressionId
- AtomicWaitId: ExpressionId
- AtomicWakeId: ExpressionId
getExpressionType(expr: Expression): Type
Gets the type of the specified expression.
getExpressionInfo(expr: Expression: ExpressionInfo
Obtains information about an expression, always including:
- Info#id: ExpressionId
- Info#type: Type
Additional properties depend on the expression's id and are usually equivalent to the respective parameters when creating such an expression:
- BlockInfo#name: string
- BlockInfo#children: Expression[]
- IfInfo#condition: Expression
- IfInfo#ifTrue: Expression
- IfInfo#ifFalse: Expression | null
- LoopInfo#name: string
- LoopInfo#body: Expression
- BreakInfo#name: string
- BreakInfo#condition: Expression | null
- BreakInfo#value: Expression | null
- SwitchInfo#names: string[]
- SwitchInfo#defaultName: string | null
- SwitchInfo#condition: Expression
- SwitchInfo#value: Expression | null
- CallInfo#target: string
- CallInfo#operands: Expression[]
- CallImportInfo#target: string
- CallImportInfo#operands: Expression[]
- CallIndirectInfo#target: Expression
- CallIndirectInfo#operands: Expression[]
- GetLocalInfo#index: number
- SetLocalInfo#isTee: boolean
- SetLocalInfo#index: number
- SetLocalInfo#value: Expression
- GetGlobalInfo#name: string
- SetGlobalInfo#name: string
- SetGlobalValue#value: Expression
- LoadInfo#isAtomic: boolean
- LoadInfo#isSigned: boolean
- LoadInfo#offset: number
- LoadInfo#bytes: number
- LoadInfo#align: number
- LoadInfo#ptr: Expression
- StoreInfo#isAtomic: boolean
- StoreInfo#offset: number
- StoreInfo#bytes: number
- StoreInfo#align: number
- StoreInfo#ptr: Expression
- StoreInfo#value: Expression
- ConstInfo#value: number | { low: number, high: number }
- UnaryInfo#op: number
- UnaryInfo#value: Expression
- BinaryInfo#op: number
- BinaryInfo#left: Expression
- BinaryInfo#right: Expression
- SelectInfo#ifTrue: Expression
- SelectInfo#ifFalse: Expression
- SelectInfo#condition: Expression
- DropInfo#value: Expression
- ReturnInfo#value: Expression | null
- HostInfo#op: number
- HostInfo#nameOperand: string | null
- HostInfo#operands: Expression[]
- AtomicRMWInfo#op: number
- AtomicRMWInfo#bytes: number
- AtomicRMWInfo#offset: number
- AtomicRMWInfo#ptr: Expression
- AtomicRMWInfo#value: Expression
- AtomicCmpxchgInfo#bytes: number
- AtomicCmpxchgInfo#offset: number
- AtomicCmpxchgInfo#ptr: Expression
- AtomicCmpxchgInfo#expected: Expression
- AtomicCmpxchgInfo#replacement: Expression
- AtomicWaitInfo#ptr: Expression
- AtomicWaitInfo#expected: Expression
- AtomicWaitInfo#timeout: Expression
- AtomicWaitInfo#expectedType: Type
- AtomicWakeInfo#ptr: Expression
- AtomicWakeInfo#wakeCount: Expression
NopInfo and UnreachableInfo do not include any additional properties.

Relooper

new Relooper(module: Module): Relooper
Constructs a relooper instance. This lets you provide an arbitrary CFG, and the relooper will structure it for WebAssembly.
Relooper#addBlock(code: Expression): RelooperBlock
Adds a new block to the CFG, containing the provided code as its body.
Relooper#addBranch(from: RelooperBlock, to: RelooperBlock, condition: Expression, code: Expression): void
Adds a branch from a block to another block, with a condition (or nothing, if this is the default branch to take from the origin - each block must have one such branch), and optional code to execute on the branch (useful for phis).
Relooper#addBlockWithSwitch(code: Expression, condition: Expression): RelooperBlock
Adds a new block, which ends with a switch/br_table, with provided code and condition (that determines where we go in the switch).
Relooper#addBranchForSwitch(from: RelooperBlock, to: RelooperBlock, indexes: number[], code: Expression): void
Adds a branch from a block ending in a switch, to another block, using an array of indexes that determine where to go, and optional code to execute on the branch.
Relooper#renderAndDispose(entry: RelooperBlock, labelHelper: number): Expression
Renders and cleans up the Relooper instance. Call this after you have created all the blocks and branches, giving it the entry block (where control flow begins) and a label helper variable (an index of a local we can use, necessary for irreducible control flow). This returns an expression - normal WebAssembly code - that you can use normally anywhere.

Source maps

Module#addDebugInfoFileName(filename: string): number
Adds a debug info file name to the module and returns its index.
Module#getDebugInfoFileName(index: number): string | null
Gets the name of the debug info file at the specified index.
Module#setDebugLocation(func: Function, expr: Expression, fileIndex: number, lineNumber: number, columnNumber: number): void
Sets the debug location of the specified Expression within the specified Function.

Debugging

Module#setAPITracing(on: boolean): void
Enables tracing of the C-API in the console. Can be very useful when filing bug reports.
Module#interpret(): void
Runs the module in the interpreter, calling the start function.

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