func (tm *llvmTypeMap) basicLLVMType(b *types.Basic) llvm.Type {
switch b.Kind() {
case types.Bool:
return llvm.Int1Type()
case types.Int8, types.Uint8:
return llvm.Int8Type()
case types.Int16, types.Uint16:
return llvm.Int16Type()
case types.Int32, types.Uint32:
return llvm.Int32Type()
case types.Uint, types.Int:
return tm.inttype
case types.Int64, types.Uint64:
return llvm.Int64Type()
case types.Float32:
return llvm.FloatType()
case types.Float64:
return llvm.DoubleType()
case types.UnsafePointer, types.Uintptr:
return tm.target.IntPtrType()
case types.Complex64:
f32 := llvm.FloatType()
elements := []llvm.Type{f32, f32}
return llvm.StructType(elements, false)
case types.Complex128:
f64 := llvm.DoubleType()
elements := []llvm.Type{f64, f64}
return llvm.StructType(elements, false)
case types.String:
i8ptr := llvm.PointerType(llvm.Int8Type(), 0)
elements := []llvm.Type{i8ptr, tm.inttype}
return llvm.StructType(elements, false)
}
panic(fmt.Sprint("unhandled kind: ", b.Kind))
}
func (tm *llvmTypeMap) funcLLVMType(f *types.Signature, name string) llvm.Type {
// If there's a receiver change the receiver to an
// additional (first) parameter, and take the value of
// the resulting signature instead.
if recv := f.Recv(); recv != nil {
params := f.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...)
f := types.NewSignature(nil, nil, params, f.Results(), f.Variadic())
return tm.toLLVM(f, name)
}
if typ, ok := tm.types.At(f).(llvm.Type); ok {
return typ
}
typ := llvm.GlobalContext().StructCreateNamed(name)
tm.types.Set(f, typ)
params := f.Params()
param_types := make([]llvm.Type, params.Len())
for i := range param_types {
llvmtyp := tm.ToLLVM(params.At(i).Type())
param_types[i] = llvmtyp
}
var return_type llvm.Type
results := f.Results()
switch nresults := int(results.Len()); nresults {
case 0:
return_type = llvm.VoidType()
case 1:
return_type = tm.ToLLVM(results.At(0).Type())
default:
elements := make([]llvm.Type, nresults)
for i := range elements {
result := results.At(i)
elements[i] = tm.ToLLVM(result.Type())
}
return_type = llvm.StructType(elements, false)
}
fntyp := llvm.FunctionType(return_type, param_types, false)
fnptrtyp := llvm.PointerType(fntyp, 0)
i8ptr := llvm.PointerType(llvm.Int8Type(), 0)
elements := []llvm.Type{fnptrtyp, i8ptr} // func, closure
typ.StructSetBody(elements, false)
return typ
}
// makeClosure creates a closure from a function pointer and
// a set of bindings. The bindings are addresses of captured
// variables.
func (c *compiler) makeClosure(fn *LLVMValue, bindings []*LLVMValue) *LLVMValue {
types := make([]llvm.Type, len(bindings))
for i, binding := range bindings {
types[i] = c.types.ToLLVM(binding.Type())
}
block := c.createTypeMalloc(llvm.StructType(types, false))
for i, binding := range bindings {
addressPtr := c.builder.CreateStructGEP(block, i, "")
c.builder.CreateStore(binding.LLVMValue(), addressPtr)
}
block = c.builder.CreateBitCast(block, llvm.PointerType(llvm.Int8Type(), 0), "")
// fn is a raw function pointer; ToLLVM yields {*fn, *uint8}.
closure := llvm.Undef(c.types.ToLLVM(fn.Type()))
fnptr := c.builder.CreateBitCast(fn.LLVMValue(), closure.Type().StructElementTypes()[0], "")
closure = c.builder.CreateInsertValue(closure, fnptr, 0, "")
closure = c.builder.CreateInsertValue(closure, block, 1, "")
return c.NewValue(closure, fn.Type())
}
func (u *unit) resolveFunction(f *ssa.Function) *LLVMValue {
if v, ok := u.globals[f]; ok {
return v
}
name := f.String()
if f.Enclosing != nil {
// Anonymous functions are not guaranteed to
// have unique identifiers at the global scope.
name = f.Enclosing.String() + ":" + name
}
// It's possible that the function already exists in the module;
// for example, if it's a runtime intrinsic that the compiler
// has already referenced.
llvmFunction := u.module.Module.NamedFunction(name)
if llvmFunction.IsNil() {
llvmType := u.llvmtypes.ToLLVM(f.Signature)
llvmType = llvmType.StructElementTypes()[0].ElementType()
if len(f.FreeVars) > 0 {
// Add an implicit first argument.
returnType := llvmType.ReturnType()
paramTypes := llvmType.ParamTypes()
vararg := llvmType.IsFunctionVarArg()
blockElementTypes := make([]llvm.Type, len(f.FreeVars))
for i, fv := range f.FreeVars {
blockElementTypes[i] = u.llvmtypes.ToLLVM(fv.Type())
}
blockType := llvm.StructType(blockElementTypes, false)
blockPtrType := llvm.PointerType(blockType, 0)
paramTypes = append([]llvm.Type{blockPtrType}, paramTypes...)
llvmType = llvm.FunctionType(returnType, paramTypes, vararg)
}
llvmFunction = llvm.AddFunction(u.module.Module, name, llvmType)
if f.Enclosing != nil {
llvmFunction.SetLinkage(llvm.PrivateLinkage)
}
u.undefinedFuncs[f] = true
}
v := u.NewValue(llvmFunction, f.Signature)
u.globals[f] = v
return v
}
// indirectFunction creates an indirect function from a
// given function and arguments, suitable for use with
// "defer" and "go".
func (c *compiler) indirectFunction(fn *LLVMValue, args []*LLVMValue) *LLVMValue {
nilarytyp := types.NewSignature(nil, nil, nil, nil, false)
if len(args) == 0 {
val := fn.LLVMValue()
ptr := c.builder.CreateExtractValue(val, 0, "")
ctx := c.builder.CreateExtractValue(val, 1, "")
fnval := llvm.Undef(c.types.ToLLVM(nilarytyp))
ptr = c.builder.CreateBitCast(ptr, fnval.Type().StructElementTypes()[0], "")
ctx = c.builder.CreateBitCast(ctx, fnval.Type().StructElementTypes()[1], "")
fnval = c.builder.CreateInsertValue(fnval, ptr, 0, "")
fnval = c.builder.CreateInsertValue(fnval, ctx, 1, "")
return c.NewValue(fnval, nilarytyp)
}
// Check if function pointer or context pointer is global/null.
fnval := fn.LLVMValue()
fnptr := fnval
var nctx int
var fnctx llvm.Value
var fnctxindex uint64
var globalfn bool
if fnptr.Type().TypeKind() == llvm.StructTypeKind {
fnptr = c.builder.CreateExtractValue(fnval, 0, "")
fnctx = c.builder.CreateExtractValue(fnval, 1, "")
globalfn = !fnptr.IsAFunction().IsNil()
if !globalfn {
nctx++
}
if !fnctx.IsNull() {
fnctxindex = uint64(nctx)
nctx++
}
} else {
// We've got a raw global function pointer. Convert to <ptr,ctx>.
fnval = llvm.ConstNull(c.types.ToLLVM(fn.Type()))
fnval = llvm.ConstInsertValue(fnval, fnptr, []uint32{0})
fn = c.NewValue(fnval, fn.Type())
fnctx = llvm.ConstExtractValue(fnval, []uint32{1})
globalfn = true
}
i8ptr := llvm.PointerType(llvm.Int8Type(), 0)
llvmargs := make([]llvm.Value, len(args)+nctx)
llvmargtypes := make([]llvm.Type, len(args)+nctx)
for i, arg := range args {
llvmargs[i+nctx] = arg.LLVMValue()
llvmargtypes[i+nctx] = llvmargs[i+nctx].Type()
}
if !globalfn {
llvmargtypes[0] = fnptr.Type()
llvmargs[0] = fnptr
}
if !fnctx.IsNull() {
llvmargtypes[fnctxindex] = fnctx.Type()
llvmargs[fnctxindex] = fnctx
}
// TODO(axw) investigate an option for go statements
// to allocate argument structure on the stack in the
// initiator, and block until the spawned goroutine
// has loaded the arguments from it.
structtyp := llvm.StructType(llvmargtypes, false)
argstruct := c.createTypeMalloc(structtyp)
for i, llvmarg := range llvmargs {
argptr := c.builder.CreateGEP(argstruct, []llvm.Value{
llvm.ConstInt(llvm.Int32Type(), 0, false),
llvm.ConstInt(llvm.Int32Type(), uint64(i), false)}, "")
c.builder.CreateStore(llvmarg, argptr)
}
// Create a function that will take a pointer to a structure of the type
// defined above, or no parameters if there are none to pass.
fntype := llvm.FunctionType(llvm.VoidType(), []llvm.Type{argstruct.Type()}, false)
indirectfn := llvm.AddFunction(c.module.Module, "", fntype)
i8argstruct := c.builder.CreateBitCast(argstruct, i8ptr, "")
currblock := c.builder.GetInsertBlock()
c.builder.SetInsertPointAtEnd(llvm.AddBasicBlock(indirectfn, "entry"))
argstruct = indirectfn.Param(0)
newargs := make([]*LLVMValue, len(args))
for i := range llvmargs[nctx:] {
argptr := c.builder.CreateGEP(argstruct, []llvm.Value{
llvm.ConstInt(llvm.Int32Type(), 0, false),
llvm.ConstInt(llvm.Int32Type(), uint64(i+nctx), false)}, "")
newargs[i] = c.NewValue(c.builder.CreateLoad(argptr, ""), args[i].Type())
}
// Unless we've got a global function, extract the
// function pointer from the context.
if !globalfn {
fnval = llvm.Undef(fnval.Type())
fnptrptr := c.builder.CreateGEP(argstruct, []llvm.Value{
llvm.ConstInt(llvm.Int32Type(), 0, false),
llvm.ConstInt(llvm.Int32Type(), 0, false)}, "")
fnptr = c.builder.CreateLoad(fnptrptr, "")
fnval = c.builder.CreateInsertValue(fnval, fnptr, 0, "")
}
if !fnctx.IsNull() {
fnctxptr := c.builder.CreateGEP(argstruct, []llvm.Value{
llvm.ConstInt(llvm.Int32Type(), 0, false),
llvm.ConstInt(llvm.Int32Type(), fnctxindex, false)}, "")
fnctx = c.builder.CreateLoad(fnctxptr, "")
fnval = c.builder.CreateInsertValue(fnval, fnctx, 1, "")
fn = c.NewValue(fnval, fn.Type())
}
c.createCall(fn, newargs)
// Indirect function calls' return values are always ignored.
c.builder.CreateRetVoid()
c.builder.SetInsertPointAtEnd(currblock)
fnval = llvm.Undef(c.types.ToLLVM(nilarytyp))
indirectfn = c.builder.CreateBitCast(indirectfn, fnval.Type().StructElementTypes()[0], "")
fnval = c.builder.CreateInsertValue(fnval, indirectfn, 0, "")
fnval = c.builder.CreateInsertValue(fnval, i8argstruct, 1, "")
fn = c.NewValue(fnval, nilarytyp)
return fn
}
func (fr *frame) instruction(instr ssa.Instruction) {
fr.logf("[%T] %v @ %s\n", instr, instr, fr.pkg.Prog.Fset.Position(instr.Pos()))
if fr.GenerateDebug {
fr.debug.setLocation(fr.builder, instr.Pos())
}
// Check if we'll need to backpatch; see comment
// in fr.value().
if v, ok := instr.(ssa.Value); ok {
if b := fr.backpatcher(v); b != nil {
defer b()
}
}
switch instr := instr.(type) {
case *ssa.Alloc:
typ := fr.llvmtypes.ToLLVM(deref(instr.Type()))
var value llvm.Value
if instr.Heap {
value = fr.createTypeMalloc(typ)
value.SetName(instr.Comment)
fr.env[instr] = fr.NewValue(value, instr.Type())
} else {
value = fr.env[instr].LLVMValue()
}
fr.memsetZero(value, llvm.SizeOf(typ))
case *ssa.BinOp:
lhs, rhs := fr.value(instr.X), fr.value(instr.Y)
fr.env[instr] = lhs.BinaryOp(instr.Op, rhs).(*LLVMValue)
case *ssa.Call:
fn, args, result := fr.prepareCall(instr)
// Some builtins may only be used immediately, and not
// deferred; in this case, "fn" will be nil, and result
// may be non-nil (it will be nil for builtins without
// results.)
if fn == nil {
if result != nil {
fr.env[instr] = result
}
} else {
result = fr.createCall(fn, args)
fr.env[instr] = result
}
case *ssa.ChangeInterface:
x := fr.value(instr.X)
// The source type must be a non-empty interface,
// as ChangeInterface cannot fail (E2I may fail).
if instr.Type().Underlying().(*types.Interface).NumMethods() > 0 {
// TODO(axw) optimisation for I2I case where we
// know statically the methods to carry over.
x = x.convertI2E()
x, _ = x.convertE2I(instr.Type())
} else {
x = x.convertI2E()
x = fr.NewValue(x.LLVMValue(), instr.Type())
}
fr.env[instr] = x
case *ssa.ChangeType:
value := fr.value(instr.X).LLVMValue()
if _, ok := instr.Type().Underlying().(*types.Pointer); ok {
value = fr.builder.CreateBitCast(value, fr.llvmtypes.ToLLVM(instr.Type()), "")
}
v := fr.NewValue(value, instr.Type())
if _, ok := instr.X.(*ssa.Phi); ok {
v = phiValue(fr.compiler, v)
}
fr.env[instr] = v
case *ssa.Convert:
v := fr.value(instr.X)
if _, ok := instr.X.(*ssa.Phi); ok {
v = phiValue(fr.compiler, v)
}
fr.env[instr] = v.Convert(instr.Type()).(*LLVMValue)
//case *ssa.DebugRef:
case *ssa.Defer:
fn, args, result := fr.prepareCall(instr)
if result != nil {
panic("illegal use of builtin in defer statement")
}
fn = fr.indirectFunction(fn, args)
fr.createCall(fr.runtime.pushdefer, []*LLVMValue{fn})
case *ssa.Extract:
tuple := fr.value(instr.Tuple).LLVMValue()
elem := fr.builder.CreateExtractValue(tuple, instr.Index, instr.Name())
elemtyp := instr.Type()
fr.env[instr] = fr.NewValue(elem, elemtyp)
case *ssa.Field:
value := fr.value(instr.X).LLVMValue()
field := fr.builder.CreateExtractValue(value, instr.Field, instr.Name())
fieldtyp := instr.Type()
fr.env[instr] = fr.NewValue(field, fieldtyp)
case *ssa.FieldAddr:
// TODO: implement nil check and panic.
// TODO: combine a chain of {Field,Index}Addrs into a single GEP.
ptr := fr.value(instr.X).LLVMValue()
fieldptr := fr.builder.CreateStructGEP(ptr, instr.Field, instr.Name())
fieldptrtyp := instr.Type()
fr.env[instr] = fr.NewValue(fieldptr, fieldptrtyp)
case *ssa.Go:
fn, args, result := fr.prepareCall(instr)
if result != nil {
panic("illegal use of builtin in go statement")
}
fn = fr.indirectFunction(fn, args)
fr.createCall(fr.runtime.Go, []*LLVMValue{fn})
case *ssa.If:
cond := fr.value(instr.Cond).LLVMValue()
block := instr.Block()
trueBlock := fr.block(block.Succs[0])
falseBlock := fr.block(block.Succs[1])
fr.builder.CreateCondBr(cond, trueBlock, falseBlock)
case *ssa.Index:
// FIXME Surely we should be dealing with an
// *array, so we can do a GEP?
array := fr.value(instr.X).LLVMValue()
arrayptr := fr.builder.CreateAlloca(array.Type(), "")
fr.builder.CreateStore(array, arrayptr)
index := fr.value(instr.Index).LLVMValue()
zero := llvm.ConstNull(index.Type())
addr := fr.builder.CreateGEP(arrayptr, []llvm.Value{zero, index}, "")
fr.env[instr] = fr.NewValue(fr.builder.CreateLoad(addr, ""), instr.Type())
case *ssa.IndexAddr:
// TODO: implement nil-check and panic.
// TODO: combine a chain of {Field,Index}Addrs into a single GEP.
x := fr.value(instr.X).LLVMValue()
index := fr.value(instr.Index).LLVMValue()
var addr llvm.Value
var elemtyp types.Type
zero := llvm.ConstNull(index.Type())
switch typ := instr.X.Type().Underlying().(type) {
case *types.Slice:
elemtyp = typ.Elem()
x = fr.builder.CreateExtractValue(x, 0, "")
addr = fr.builder.CreateGEP(x, []llvm.Value{index}, "")
case *types.Pointer: // *array
elemtyp = typ.Elem().Underlying().(*types.Array).Elem()
addr = fr.builder.CreateGEP(x, []llvm.Value{zero, index}, "")
}
fr.env[instr] = fr.NewValue(addr, types.NewPointer(elemtyp))
case *ssa.Jump:
succ := instr.Block().Succs[0]
fr.builder.CreateBr(fr.block(succ))
case *ssa.Lookup:
x := fr.value(instr.X)
index := fr.value(instr.Index)
if isString(x.Type().Underlying()) {
fr.env[instr] = fr.stringIndex(x, index)
} else {
fr.env[instr] = fr.mapLookup(x, index, instr.CommaOk)
}
case *ssa.MakeChan:
fr.env[instr] = fr.makeChan(instr.Type(), fr.value(instr.Size))
case *ssa.MakeClosure:
fn := fr.resolveFunction(instr.Fn.(*ssa.Function))
bindings := make([]*LLVMValue, len(instr.Bindings))
for i, binding := range instr.Bindings {
bindings[i] = fr.value(binding)
}
fr.env[instr] = fr.makeClosure(fn, bindings)
case *ssa.MakeInterface:
receiver := fr.value(instr.X)
fr.env[instr] = fr.makeInterface(receiver, instr.Type())
case *ssa.MakeMap:
fr.env[instr] = fr.makeMap(instr.Type(), fr.value(instr.Reserve))
case *ssa.MakeSlice:
length := fr.value(instr.Len)
capacity := fr.value(instr.Cap)
fr.env[instr] = fr.makeSlice(instr.Type(), length, capacity)
case *ssa.MapUpdate:
m := fr.value(instr.Map)
k := fr.value(instr.Key)
v := fr.value(instr.Value)
fr.mapUpdate(m, k, v)
case *ssa.Next:
iter := fr.value(instr.Iter)
if !instr.IsString {
fr.env[instr] = fr.mapIterNext(iter)
return
}
// String range
//
// We make some assumptions for now around the
// current state of affairs in go.tools/ssa.
//
// - Range's block is a predecessor of Next's.
// (this is currently true, but may change in the future;
// adonovan says he will expose the dominator tree
// computation in the future, which we can use here).
// - Next is the first non-Phi instruction in its block.
// (this is not strictly necessary; we can move the Phi
// to the top of the block, and defer the tuple creation
// to Extract).
assert(instr.Iter.(*ssa.Range).Block() == instr.Block().Preds[0])
for _, blockInstr := range instr.Block().Instrs {
if instr == blockInstr {
break
}
_, isphi := blockInstr.(*ssa.Phi)
assert(isphi)
}
preds := instr.Block().Preds
llpreds := make([]llvm.BasicBlock, len(preds))
for i, b := range preds {
llpreds[i] = fr.block(b)
}
fr.env[instr] = fr.stringIterNext(iter, llpreds)
case *ssa.Panic:
arg := fr.value(instr.X).LLVMValue()
fr.builder.CreateCall(fr.runtime.panic_.LLVMValue(), []llvm.Value{arg}, "")
fr.builder.CreateUnreachable()
case *ssa.Phi:
typ := instr.Type()
phi := fr.builder.CreatePHI(fr.llvmtypes.ToLLVM(typ), instr.Comment)
fr.env[instr] = fr.NewValue(phi, typ)
values := make([]llvm.Value, len(instr.Edges))
blocks := make([]llvm.BasicBlock, len(instr.Edges))
block := instr.Block()
for i, edge := range instr.Edges {
values[i] = fr.value(edge).LLVMValue()
blocks[i] = fr.block(block.Preds[i])
}
phi.AddIncoming(values, blocks)
case *ssa.Range:
x := fr.value(instr.X)
switch x.Type().Underlying().(type) {
case *types.Map:
fr.env[instr] = fr.mapIterInit(x)
case *types.Basic: // string
fr.env[instr] = x
default:
panic(fmt.Sprintf("unhandled range for type %T", x.Type()))
}
case *ssa.Return:
switch n := len(instr.Results); n {
case 0:
// https://code.google.com/p/go/issues/detail?id=7022
if r := instr.Parent().Signature.Results(); r != nil && r.Len() > 0 {
fr.builder.CreateUnreachable()
} else {
fr.builder.CreateRetVoid()
}
case 1:
fr.builder.CreateRet(fr.value(instr.Results[0]).LLVMValue())
default:
values := make([]llvm.Value, n)
for i, result := range instr.Results {
values[i] = fr.value(result).LLVMValue()
}
fr.builder.CreateAggregateRet(values)
}
case *ssa.RunDefers:
fr.builder.CreateCall(fr.runtime.rundefers.LLVMValue(), nil, "")
case *ssa.Select:
states := make([]selectState, len(instr.States))
for i, state := range instr.States {
states[i] = selectState{
Dir: state.Dir,
Chan: fr.value(state.Chan),
Send: fr.value(state.Send),
}
}
fr.env[instr] = fr.chanSelect(states, instr.Blocking)
case *ssa.Send:
fr.chanSend(fr.value(instr.Chan), fr.value(instr.X))
case *ssa.Slice:
x := fr.value(instr.X)
low := fr.value(instr.Low)
high := fr.value(instr.High)
fr.env[instr] = fr.slice(x, low, high)
case *ssa.Store:
addr := fr.value(instr.Addr).LLVMValue()
value := fr.value(instr.Val).LLVMValue()
// The bitcast is necessary to handle recursive pointer stores.
addr = fr.builder.CreateBitCast(addr, llvm.PointerType(value.Type(), 0), "")
fr.builder.CreateStore(value, addr)
case *ssa.TypeAssert:
x := fr.value(instr.X)
if iface, ok := x.Type().Underlying().(*types.Interface); ok && iface.NumMethods() > 0 {
x = x.convertI2E()
}
if !instr.CommaOk {
if _, ok := instr.AssertedType.Underlying().(*types.Interface); ok {
fr.env[instr] = x.mustConvertE2I(instr.AssertedType)
} else {
fr.env[instr] = x.mustConvertE2V(instr.AssertedType)
}
} else {
var result, success *LLVMValue
if _, ok := instr.AssertedType.Underlying().(*types.Interface); ok {
result, success = x.convertE2I(instr.AssertedType)
} else {
result, success = x.convertE2V(instr.AssertedType)
}
resultval := result.LLVMValue()
okval := success.LLVMValue()
pairtyp := llvm.StructType([]llvm.Type{resultval.Type(), okval.Type()}, false)
pair := llvm.Undef(pairtyp)
pair = fr.builder.CreateInsertValue(pair, resultval, 0, "")
pair = fr.builder.CreateInsertValue(pair, okval, 1, "")
fr.env[instr] = fr.NewValue(pair, instr.Type())
}
case *ssa.UnOp:
operand := fr.value(instr.X)
switch instr.Op {
case token.ARROW:
fr.env[instr] = fr.chanRecv(operand, instr.CommaOk)
case token.MUL:
// The bitcast is necessary to handle recursive pointer loads.
llptr := fr.builder.CreateBitCast(operand.LLVMValue(), llvm.PointerType(fr.llvmtypes.ToLLVM(instr.Type()), 0), "")
fr.env[instr] = fr.NewValue(fr.builder.CreateLoad(llptr, ""), instr.Type())
default:
fr.env[instr] = operand.UnaryOp(instr.Op).(*LLVMValue)
}
default:
panic(fmt.Sprintf("unhandled: %v", instr))
}
}
