func (d *DIBuilder) descriptorInterface(t *types.Interface, name string) llvm.Metadata {
ifaceStruct := types.NewStruct([]*types.Var{
types.NewVar(0, nil, "type", types.NewPointer(types.Typ[types.Uint8])),
types.NewVar(0, nil, "data", types.NewPointer(types.Typ[types.Uint8])),
}, nil)
return d.typeDebugDescriptor(ifaceStruct, name)
}
func (d *DIBuilder) descriptorSlice(t *types.Slice, name string) llvm.Metadata {
sliceStruct := types.NewStruct([]*types.Var{
types.NewVar(0, nil, "ptr", types.NewPointer(t.Elem())),
types.NewVar(0, nil, "len", types.Typ[types.Int]),
types.NewVar(0, nil, "cap", types.Typ[types.Int]),
}, nil)
return d.typeDebugDescriptor(sliceStruct, name)
}
func (d *DIBuilder) descriptorSignature(t *types.Signature, name string) llvm.Metadata {
// If there's a receiver change the receiver to an
// additional (first) parameter, and take the value of
// the resulting signature instead.
if recv := t.Recv(); recv != nil {
params := t.Params()
paramvars := make([]*types.Var, int(params.Len()+1))
paramvars[0] = recv
for i := 0; i < int(params.Len()); i++ {
paramvars[i+1] = params.At(i)
}
params = types.NewTuple(paramvars...)
t := types.NewSignature(nil, nil, params, t.Results(), t.Variadic())
return d.typeDebugDescriptor(t, name)
}
if dt, ok := d.types.At(t).(llvm.Metadata); ok {
return dt
}
var returnType llvm.Metadata
results := t.Results()
switch n := results.Len(); n {
case 0:
returnType = d.DIType(nil) // void
case 1:
returnType = d.DIType(results.At(0).Type())
default:
fields := make([]*types.Var, results.Len())
for i := range fields {
f := results.At(i)
// Structs may not have multiple fields
// with the same name, excepting "_".
if f.Name() == "" {
f = types.NewVar(f.Pos(), f.Pkg(), "_", f.Type())
}
fields[i] = f
}
returnType = d.typeDebugDescriptor(types.NewStruct(fields, nil), "")
}
var paramTypes []llvm.Metadata
params := t.Params()
if params != nil && params.Len() > 0 {
paramTypes = make([]llvm.Metadata, params.Len()+1)
paramTypes[0] = returnType
for i := range paramTypes[1:] {
paramTypes[i+1] = d.DIType(params.At(i).Type())
}
} else {
paramTypes = []llvm.Metadata{returnType}
}
// TODO(axw) get position of type definition for File field
return d.builder.CreateSubroutineType(llvm.DISubroutineType{
Parameters: paramTypes,
})
}
// makeClosure creates a closure from a function pointer and
// a set of bindings. The bindings are addresses of captured
// variables.
func (fr *frame) makeClosure(fn *govalue, bindings []*govalue) *govalue {
govalues := append([]*govalue{fn}, bindings...)
fields := make([]*types.Var, len(govalues))
for i, v := range govalues {
field := types.NewField(0, nil, "_", v.Type(), false)
fields[i] = field
}
block := fr.createTypeMalloc(types.NewStruct(fields, nil))
for i, v := range govalues {
addressPtr := fr.builder.CreateStructGEP(block, i, "")
fr.builder.CreateStore(v.value, addressPtr)
}
closure := fr.builder.CreateBitCast(block, fn.value.Type(), "")
return newValue(closure, fn.Type())
}
// StructType = "struct" "{" { Field } "}" .
func (p *parser) parseStructType(pkg *types.Package) types.Type {
p.expectKeyword("struct")
var fields []*types.Var
var tags []string
p.expect('{')
for p.tok != '}' && p.tok != scanner.EOF {
field, tag := p.parseField(pkg)
p.expect(';')
fields = append(fields, field)
tags = append(tags, tag)
}
p.expect('}')
return types.NewStruct(fields, tags)
}
func initReflect(i *interpreter) {
i.reflectPackage = &ssa.Package{
Prog: i.prog,
Object: reflectTypesPackage,
Members: make(map[string]ssa.Member),
}
// Clobber the type-checker's notion of reflect.Value's
// underlying type so that it more closely matches the fake one
// (at least in the number of fields---we lie about the type of
// the rtype field).
//
// We must ensure that calls to (ssa.Value).Type() return the
// fake type so that correct "shape" is used when allocating
// variables, making zero values, loading, and storing.
//
// TODO(adonovan): obviously this is a hack. We need a cleaner
// way to fake the reflect package (almost---DeepEqual is fine).
// One approach would be not to even load its source code, but
// provide fake source files. This would guarantee that no bad
// information leaks into other packages.
if r := i.prog.ImportedPackage("reflect"); r != nil {
rV := r.Object.Scope().Lookup("Value").Type().(*types.Named)
tEface := types.NewInterface(nil, nil).Complete()
rV.SetUnderlying(types.NewStruct([]*types.Var{
types.NewField(token.NoPos, r.Object, "t", tEface, false), // a lie
types.NewField(token.NoPos, r.Object, "v", tEface, false),
}, nil))
}
i.rtypeMethods = methodSet{
"Bits": newMethod(i.reflectPackage, rtypeType, "Bits"),
"Elem": newMethod(i.reflectPackage, rtypeType, "Elem"),
"Field": newMethod(i.reflectPackage, rtypeType, "Field"),
"Kind": newMethod(i.reflectPackage, rtypeType, "Kind"),
"NumField": newMethod(i.reflectPackage, rtypeType, "NumField"),
"NumMethod": newMethod(i.reflectPackage, rtypeType, "NumMethod"),
"NumOut": newMethod(i.reflectPackage, rtypeType, "NumOut"),
"Out": newMethod(i.reflectPackage, rtypeType, "Out"),
"Size": newMethod(i.reflectPackage, rtypeType, "Size"),
"String": newMethod(i.reflectPackage, rtypeType, "String"),
}
i.errorMethods = methodSet{
"Error": newMethod(i.reflectPackage, errorType, "Error"),
}
}
func (d *DIBuilder) descriptorBasic(t *types.Basic, name string) llvm.Metadata {
switch t.Kind() {
case types.String:
return d.typeDebugDescriptor(types.NewStruct([]*types.Var{
types.NewVar(0, nil, "ptr", types.NewPointer(types.Typ[types.Uint8])),
types.NewVar(0, nil, "len", types.Typ[types.Int]),
}, nil), name)
case types.UnsafePointer:
return d.builder.CreateBasicType(llvm.DIBasicType{
Name: name,
SizeInBits: uint64(d.sizes.Sizeof(t) * 8),
AlignInBits: uint64(d.sizes.Alignof(t) * 8),
Encoding: llvm.DW_ATE_unsigned,
})
default:
bt := llvm.DIBasicType{
Name: t.String(),
SizeInBits: uint64(d.sizes.Sizeof(t) * 8),
AlignInBits: uint64(d.sizes.Alignof(t) * 8),
}
switch bi := t.Info(); {
case bi&types.IsBoolean != 0:
bt.Encoding = llvm.DW_ATE_boolean
case bi&types.IsUnsigned != 0:
bt.Encoding = llvm.DW_ATE_unsigned
case bi&types.IsInteger != 0:
bt.Encoding = llvm.DW_ATE_signed
case bi&types.IsFloat != 0:
bt.Encoding = llvm.DW_ATE_float
case bi&types.IsComplex != 0:
bt.Encoding = llvm.DW_ATE_imaginary_float
case bi&types.IsUnsigned != 0:
bt.Encoding = llvm.DW_ATE_unsigned
default:
panic(fmt.Sprintf("unhandled: %#v", t))
}
return d.builder.CreateBasicType(bt)
}
}
// StructType = "struct" "{" [ FieldList ] "}" .
// FieldList = Field { ";" Field } .
//
func (p *parser) parseStructType() types.Type {
var fields []*types.Var
var tags []string
p.expectKeyword("struct")
p.expect('{')
for i := 0; p.tok != '}' && p.tok != scanner.EOF; i++ {
if i > 0 {
p.expect(';')
}
fld, tag := p.parseField()
if tag != "" && tags == nil {
tags = make([]string, i)
}
if tags != nil {
tags = append(tags, tag)
}
fields = append(fields, fld)
}
p.expect('}')
return types.NewStruct(fields, tags)
}
// createThunk creates a thunk from a
// given function and arguments, suitable for use with
// "defer" and "go".
func (fr *frame) createThunk(call ssa.CallInstruction) (thunk llvm.Value, arg llvm.Value) {
seenarg := make(map[ssa.Value]bool)
var args []ssa.Value
var argtypes []*types.Var
packArg := func(arg ssa.Value) {
switch arg.(type) {
case *ssa.Builtin, *ssa.Function, *ssa.Const, *ssa.Global:
// Do nothing: we can generate these in the thunk
default:
if !seenarg[arg] {
seenarg[arg] = true
args = append(args, arg)
field := types.NewField(0, nil, "_", arg.Type(), true)
argtypes = append(argtypes, field)
}
}
}
packArg(call.Common().Value)
for _, arg := range call.Common().Args {
packArg(arg)
}
var isRecoverCall bool
i8ptr := llvm.PointerType(llvm.Int8Type(), 0)
var structllptr llvm.Type
if len(args) == 0 {
if builtin, ok := call.Common().Value.(*ssa.Builtin); ok {
isRecoverCall = builtin.Name() == "recover"
}
if isRecoverCall {
// When creating a thunk for recover(), we must pass fr.canRecover.
arg = fr.builder.CreateZExt(fr.canRecover, fr.target.IntPtrType(), "")
arg = fr.builder.CreateIntToPtr(arg, i8ptr, "")
} else {
arg = llvm.ConstPointerNull(i8ptr)
}
} else {
structtype := types.NewStruct(argtypes, nil)
arg = fr.createTypeMalloc(structtype)
structllptr = arg.Type()
for i, ssaarg := range args {
argptr := fr.builder.CreateStructGEP(arg, i, "")
fr.builder.CreateStore(fr.llvmvalue(ssaarg), argptr)
}
arg = fr.builder.CreateBitCast(arg, i8ptr, "")
}
thunkfntype := llvm.FunctionType(llvm.VoidType(), []llvm.Type{i8ptr}, false)
thunkfn := llvm.AddFunction(fr.module.Module, "", thunkfntype)
thunkfn.SetLinkage(llvm.InternalLinkage)
fr.addCommonFunctionAttrs(thunkfn)
thunkfr := newFrame(fr.unit, thunkfn)
defer thunkfr.dispose()
prologuebb := llvm.AddBasicBlock(thunkfn, "prologue")
thunkfr.builder.SetInsertPointAtEnd(prologuebb)
if isRecoverCall {
thunkarg := thunkfn.Param(0)
thunkarg = thunkfr.builder.CreatePtrToInt(thunkarg, fr.target.IntPtrType(), "")
thunkfr.canRecover = thunkfr.builder.CreateTrunc(thunkarg, llvm.Int1Type(), "")
} else if len(args) > 0 {
thunkarg := thunkfn.Param(0)
thunkarg = thunkfr.builder.CreateBitCast(thunkarg, structllptr, "")
for i, ssaarg := range args {
thunkargptr := thunkfr.builder.CreateStructGEP(thunkarg, i, "")
thunkarg := thunkfr.builder.CreateLoad(thunkargptr, "")
thunkfr.env[ssaarg] = newValue(thunkarg, ssaarg.Type())
}
}
_, isDefer := call.(*ssa.Defer)
entrybb := llvm.AddBasicBlock(thunkfn, "entry")
br := thunkfr.builder.CreateBr(entrybb)
thunkfr.allocaBuilder.SetInsertPointBefore(br)
thunkfr.builder.SetInsertPointAtEnd(entrybb)
var exitbb llvm.BasicBlock
if isDefer {
exitbb = llvm.AddBasicBlock(thunkfn, "exit")
thunkfr.runtime.setDeferRetaddr.call(thunkfr, llvm.BlockAddress(thunkfn, exitbb))
}
if isDefer && isRecoverCall {
thunkfr.callRecover(true)
} else {
thunkfr.callInstruction(call)
}
if isDefer {
thunkfr.builder.CreateBr(exitbb)
thunkfr.builder.SetInsertPointAtEnd(exitbb)
}
thunkfr.builder.CreateRetVoid()
thunk = fr.builder.CreateBitCast(thunkfn, i8ptr, "")
return
}
func (p *importer) typ() types.Type {
// if the type was seen before, i is its index (>= 0)
i := p.int()
if i >= 0 {
return p.typList[i]
}
// otherwise, i is the type tag (< 0)
switch i {
case arrayTag:
t := new(types.Array)
p.record(t)
n := p.int64()
*t = *types.NewArray(p.typ(), n)
return t
case sliceTag:
t := new(types.Slice)
p.record(t)
*t = *types.NewSlice(p.typ())
return t
case structTag:
t := new(types.Struct)
p.record(t)
n := p.int()
fields := make([]*types.Var, n)
tags := make([]string, n)
for i := range fields {
fields[i] = p.field()
tags[i] = p.string()
}
*t = *types.NewStruct(fields, tags)
return t
case pointerTag:
t := new(types.Pointer)
p.record(t)
*t = *types.NewPointer(p.typ())
return t
case signatureTag:
t := new(types.Signature)
p.record(t)
*t = *p.signature()
return t
case interfaceTag:
// Create a dummy entry in the type list. This is safe because we
// cannot expect the interface type to appear in a cycle, as any
// such cycle must contain a named type which would have been
// first defined earlier.
n := len(p.typList)
p.record(nil)
// read embedded interfaces
embeddeds := make([]*types.Named, p.int())
for i := range embeddeds {
embeddeds[i] = p.typ().(*types.Named)
}
// read methods
methods := make([]*types.Func, p.int())
for i := range methods {
pkg, name := p.qualifiedName()
methods[i] = types.NewFunc(token.NoPos, pkg, name, p.typ().(*types.Signature))
}
t := types.NewInterface(methods, embeddeds)
p.typList[n] = t
return t
case mapTag:
t := new(types.Map)
p.record(t)
*t = *types.NewMap(p.typ(), p.typ())
return t
case chanTag:
t := new(types.Chan)
p.record(t)
*t = *types.NewChan(types.ChanDir(p.int()), p.typ())
return t
case namedTag:
// read type object
name := p.string()
pkg := p.pkg()
scope := pkg.Scope()
obj := scope.Lookup(name)
// if the object doesn't exist yet, create and insert it
if obj == nil {
obj = types.NewTypeName(token.NoPos, pkg, name, nil)
scope.Insert(obj)
}
// associate new named type with obj if it doesn't exist yet
t0 := types.NewNamed(obj.(*types.TypeName), nil, nil)
// but record the existing type, if any
t := obj.Type().(*types.Named)
p.record(t)
// read underlying type
t0.SetUnderlying(p.typ())
// read associated methods
for i, n := 0, p.int(); i < n; i++ {
t0.AddMethod(types.NewFunc(token.NoPos, pkg, p.string(), p.typ().(*types.Signature)))
}
return t
default:
panic(fmt.Sprintf("unexpected type tag %d", i))
}
}