diff options
Diffstat (limited to 'compiler/symbol.go')
| -rw-r--r-- | compiler/symbol.go | 48 |
1 files changed, 39 insertions, 9 deletions
diff --git a/compiler/symbol.go b/compiler/symbol.go index bf5ac5f1b..5ebdee147 100644 --- a/compiler/symbol.go +++ b/compiler/symbol.go @@ -346,7 +346,7 @@ func (c *compilerContext) parsePragmas(info *functionInfo, f *ssa.Function) { // The list of allowed types is based on this proposal: // https://github.com/golang/go/issues/59149 func (c *compilerContext) checkWasmImport(f *ssa.Function, pragma string) { - if c.pkg.Path() == "runtime" || c.pkg.Path() == "syscall/js" { + if c.pkg.Path() == "runtime" || c.pkg.Path() == "syscall/js" || c.pkg.Path() == "syscall" { // The runtime is a special case. Allow all kinds of parameters // (importantly, including pointers). return @@ -360,38 +360,68 @@ func (c *compilerContext) checkWasmImport(f *ssa.Function, pragma string) { c.addError(f.Signature.Results().At(1).Pos(), fmt.Sprintf("%s: too many return values", pragma)) } else if f.Signature.Results().Len() == 1 { result := f.Signature.Results().At(0) - if !isValidWasmType(result.Type(), true) { + if !isValidWasmType(result.Type(), siteResult) { c.addError(result.Pos(), fmt.Sprintf("%s: unsupported result type %s", pragma, result.Type().String())) } } for _, param := range f.Params { // Check whether the type is allowed. // Only a very limited number of types can be mapped to WebAssembly. - if !isValidWasmType(param.Type(), false) { + if !isValidWasmType(param.Type(), siteParam) { c.addError(param.Pos(), fmt.Sprintf("%s: unsupported parameter type %s", pragma, param.Type().String())) } } } -// Check whether the type maps directly to a WebAssembly type, according to: +// Check whether the type maps directly to a WebAssembly type. +// +// This reflects the relaxed type restrictions proposed here (except for structs.HostLayout): +// https://github.com/golang/go/issues/66984 +// +// This previously reflected the additional restrictions documented here: // https://github.com/golang/go/issues/59149 -func isValidWasmType(typ types.Type, isReturn bool) bool { +func isValidWasmType(typ types.Type, site wasmSite) bool { switch typ := typ.Underlying().(type) { case *types.Basic: switch typ.Kind() { - case types.Int32, types.Uint32, types.Int64, types.Uint64: + case types.Bool: + return true + case types.Int, types.Uint, types.Int8, types.Uint8, types.Int16, types.Uint16, types.Int32, types.Uint32, types.Int64, types.Uint64: return true case types.Float32, types.Float64: return true - case types.UnsafePointer: - if !isReturn { - return true + case types.Uintptr, types.UnsafePointer: + return true + case types.String: + // string flattens to two values, so disallowed as a result + return site == siteParam || site == siteIndirect + } + case *types.Array: + return site == siteIndirect && isValidWasmType(typ.Elem(), siteIndirect) + case *types.Struct: + if site != siteIndirect { + return false + } + for i := 0; i < typ.NumFields(); i++ { + if !isValidWasmType(typ.Field(i).Type(), siteIndirect) { + return false } } + return true + case *types.Pointer: + return isValidWasmType(typ.Elem(), siteIndirect) } return false } +type wasmSite int + +const ( + siteParam wasmSite = iota + siteResult + siteIndirect // pointer or field +) + // getParams returns the function parameters, including the receiver at the // start. This is an alternative to the Params member of *ssa.Function, which is // not yet populated when the package has not yet been built. |