Golang llvm.AddGlobal函數代碼示例

func (tm *TypeMap) nameRuntimeType(n *types.Named) (global, ptr llvm.Value) {
	name := typeString(n)
	path := "runtime"
	if pkg := n.Obj().Pkg(); pkg != nil {
		path = pkg.Path()
	}
	if path != tm.pkgpath {
		// We're not compiling the package from whence the type came,
		// so we'll just create a pointer to it here.
		global := llvm.AddGlobal(tm.module, tm.runtime.rtype.llvm, typeSymbol(name))
		global.SetInitializer(llvm.ConstNull(tm.runtime.rtype.llvm))
		global.SetLinkage(llvm.CommonLinkage)
		return global, global
	}

	// If the underlying type is Basic, then we always create
	// a new global. Otherwise, we clone the value returned
	// from toRuntime in case it is cached and reused.
	underlying := n.Underlying()
	if basic, ok := underlying.(*types.Basic); ok {
		global, ptr = tm.basicRuntimeType(basic, true)
		global.SetName(typeSymbol(name))
	} else {
		global, ptr = tm.toRuntime(underlying)
		clone := llvm.AddGlobal(tm.module, global.Type().ElementType(), typeSymbol(name))
		clone.SetInitializer(global.Initializer())
		global = clone
		ptr = llvm.ConstBitCast(global, llvm.PointerType(tm.runtime.rtype.llvm, 0))
	}
	global.SetLinkage(llvm.ExternalLinkage)

	// Locate the rtype.
	underlyingRuntimeType := global.Initializer()
	rtype := underlyingRuntimeType
	if rtype.Type() != tm.runtime.rtype.llvm {
		rtype = llvm.ConstExtractValue(rtype, []uint32{0})
	}

	// Insert the uncommon type.
	uncommonTypeInit := tm.uncommonType(n, nil)
	uncommonType := llvm.AddGlobal(tm.module, uncommonTypeInit.Type(), "")
	uncommonType.SetInitializer(uncommonTypeInit)
	rtype = llvm.ConstInsertValue(rtype, uncommonType, []uint32{9})

	// Replace the rtype's string representation with the one from
	// uncommonType. XXX should we have the package name prepended? Probably.
	namePtr := llvm.ConstExtractValue(uncommonTypeInit, []uint32{0})
	rtype = llvm.ConstInsertValue(rtype, namePtr, []uint32{8})

	// Update the global's initialiser. Note that we take a copy
	// of the underlying type; we're not updating a shared type.
	if underlyingRuntimeType.Type() != tm.runtime.rtype.llvm {
		underlyingRuntimeType = llvm.ConstInsertValue(underlyingRuntimeType, rtype, []uint32{0})
	} else {
		underlyingRuntimeType = rtype
	}
	global.SetInitializer(underlyingRuntimeType)
	return global, ptr
}

func (tm *TypeMap) nameRuntimeType(n *types.Named) (global, ptr llvm.Value) {
	var path string
	if data, ok := tm.functions.objectdata[n.Obj()]; ok {
		path = pkgpath(data.Package)
	}
	if path == "" {
		// Set to "runtime", so the builtin types have a home.
		path = "runtime"
	}
	globalname := "__llgo.type." + path + "." + n.Obj().Name()
	if path != tm.pkgpath {
		// We're not compiling the package from whence the type came,
		// so we'll just create a pointer to it here.
		global := llvm.AddGlobal(tm.module, tm.runtimeType, globalname)
		global.SetInitializer(llvm.ConstNull(tm.runtimeType))
		global.SetLinkage(llvm.CommonLinkage)
		return global, global
	}

	underlying := n.Underlying()
	if name, ok := underlying.(*types.Named); ok {
		underlying = name.Underlying()
	}

	global, ptr = tm.toRuntime(underlying)

	// Locate the rtype.
	underlyingRuntimeType := global.Initializer()
	rtype := underlyingRuntimeType
	if rtype.Type() != tm.runtimeType {
		rtype = llvm.ConstExtractValue(rtype, []uint32{0})
	}

	// Insert the uncommon type.
	uncommonTypeInit := tm.uncommonType(n, false)
	uncommonType := llvm.AddGlobal(tm.module, uncommonTypeInit.Type(), "")
	uncommonType.SetInitializer(uncommonTypeInit)
	rtype = llvm.ConstInsertValue(rtype, uncommonType, []uint32{9})

	// Replace the rtype's string representation with the one from
	// uncommonType. XXX should we have the package name prepended? Probably.
	namePtr := llvm.ConstExtractValue(uncommonTypeInit, []uint32{0})
	rtype = llvm.ConstInsertValue(rtype, namePtr, []uint32{8})

	// Update the global's initialiser. Note that we take a copy
	// of the underlying type; we're not updating a shared type.
	if underlyingRuntimeType.Type() != tm.runtimeType {
		underlyingRuntimeType = llvm.ConstInsertValue(underlyingRuntimeType, rtype, []uint32{0})
	} else {
		underlyingRuntimeType = rtype
	}
	global.SetName(globalname)
	global.SetInitializer(underlyingRuntimeType)
	return global, ptr
}

// globalStringPtr returns a *string with the specified value.
func (tm *TypeMap) globalStringPtr(value string) llvm.Value {
	strval := llvm.ConstString(value, false)
	strglobal := llvm.AddGlobal(tm.module, strval.Type(), "")
	strglobal.SetInitializer(strval)
	strglobal = llvm.ConstBitCast(strglobal, llvm.PointerType(llvm.Int8Type(), 0))
	strlen := llvm.ConstInt(tm.inttype, uint64(len(value)), false)
	str := llvm.ConstStruct([]llvm.Value{strglobal, strlen}, false)
	g := llvm.AddGlobal(tm.module, str.Type(), "")
	g.SetInitializer(str)
	return g
}

func (tm *TypeMap) pointerRuntimeType(p *types.Pointer) (global, ptr llvm.Value) {
	// Is the base type a named type from another package? If so, we'll
	// create a reference to the externally defined symbol.
	var globalname string
	if n, ok := p.Base.(*types.Name); ok {
		pkgpath := n.Package
		if pkgpath == "" {
			pkgpath = "runtime"
		}
		globalname = "__llgo.type.*" + n.String()
		if pkgpath != tm.pkgpath {
			global := llvm.AddGlobal(tm.module, tm.runtimeType, globalname)
			global.SetInitializer(llvm.ConstNull(tm.runtimeType))
			global.SetLinkage(llvm.CommonLinkage)
			return global, global
		}
	}

	commonType := tm.makeCommonType(p, reflect.Ptr)
	if n, ok := p.Base.(*types.Name); ok {
		uncommonTypeInit := tm.uncommonType(n, true)
		uncommonType := llvm.AddGlobal(tm.module, uncommonTypeInit.Type(), "")
		uncommonType.SetInitializer(uncommonTypeInit)
		commonType = llvm.ConstInsertValue(commonType, uncommonType, []uint32{9})
	}

	baseTypeGlobal, baseTypePtr := tm.toRuntime(p.Base)
	ptrType := llvm.ConstNull(tm.runtimePtrType)
	ptrType = llvm.ConstInsertValue(ptrType, commonType, []uint32{0})
	ptrType = llvm.ConstInsertValue(ptrType, baseTypePtr, []uint32{1})
	global, ptr = tm.makeRuntimeTypeGlobal(ptrType)
	global.SetName(globalname)

	// Set ptrToThis in the base type's commonType.
	baseRuntimeType := baseTypeGlobal.Initializer()
	baseType := llvm.ConstExtractValue(baseRuntimeType, []uint32{1})
	if baseType.Type() == tm.runtimeCommonType {
		baseType = llvm.ConstInsertValue(baseType, ptr, []uint32{10})
	} else {
		commonType := llvm.ConstExtractValue(baseType, []uint32{0})
		commonType = llvm.ConstInsertValue(commonType, ptr, []uint32{10})
		baseType = llvm.ConstInsertValue(baseType, commonType, []uint32{0})
	}
	baseRuntimeType = llvm.ConstInsertValue(baseRuntimeType, baseType, []uint32{1})
	baseTypeGlobal.SetInitializer(baseRuntimeType)

	return global, ptr
}

// basicRuntimeType creates the runtime type structure for
// a basic type. If underlying is true, then a new global
// is always created.
func (tm *TypeMap) basicRuntimeType(b *types.Basic, underlying bool) (global, ptr llvm.Value) {
	b = types.Typ[b.Kind()] // unalias
	var name string
	if !underlying {
		name = typeString(b)
		if tm.pkgpath != "runtime" {
			global := llvm.AddGlobal(tm.module, tm.runtime.rtype.llvm, typeSymbol(name))
			global.SetInitializer(llvm.ConstNull(tm.runtime.rtype.llvm))
			global.SetLinkage(llvm.CommonLinkage)
			return global, global
		}
	}
	rtype := tm.makeRtype(b, basicReflectKinds[b.Kind()])
	global, ptr = tm.makeRuntimeTypeGlobal(rtype, name)
	global.SetLinkage(llvm.ExternalLinkage)
	if !underlying {
		switch b.Kind() {
		case types.Int32:
			llvm.AddAlias(tm.module, global.Type(), global, typeSymbol("rune"))
		case types.Uint8:
			llvm.AddAlias(tm.module, global.Type(), global, typeSymbol("byte"))
		}
	}
	return global, ptr
}

func (tm *TypeMap) makeRuntimeTypeGlobal(v llvm.Value, name string) (global, ptr llvm.Value) {
	global = llvm.AddGlobal(tm.module, v.Type(), typeSymbol(name))
	global.SetInitializer(v)
	global.SetLinkage(llvm.LinkOnceAnyLinkage)
	ptr = llvm.ConstBitCast(global, llvm.PointerType(tm.runtime.rtype.llvm, 0))
	return global, ptr
}

func (tm *TypeMap) nameRuntimeType(n *types.Name) (global, ptr llvm.Value) {
	global, ptr = tm.makeRuntimeType(n.Underlying)
	globalInit := global.Initializer()

	// Locate the common type.
	underlyingRuntimeType := llvm.ConstExtractValue(globalInit, []uint32{1})
	commonType := underlyingRuntimeType
	if _, ok := n.Underlying.(*types.Basic); !ok {
		commonType = llvm.ConstExtractValue(commonType, []uint32{0})
	}

	// Insert the uncommon type.
	uncommonTypeInit := llvm.ConstNull(tm.runtimeUncommonType)
	uncommonType := llvm.AddGlobal(tm.module, uncommonTypeInit.Type(), "")
	uncommonType.SetInitializer(uncommonTypeInit)
	commonType = llvm.ConstInsertValue(commonType, uncommonType, []uint32{8})

	// Update the global's initialiser.
	if _, ok := n.Underlying.(*types.Basic); !ok {
		underlyingRuntimeType = llvm.ConstInsertValue(underlyingRuntimeType, commonType, []uint32{0})
	} else {
		underlyingRuntimeType = commonType
	}
	globalInit = llvm.ConstInsertValue(globalInit, underlyingRuntimeType, []uint32{1})
	global.SetName("__llgo.reflect." + n.Obj.Name)
	return global, ptr
}

// mapLookup searches a map for a specified key, returning a pointer to the
// memory location for the value. If insert is given as true, and the key
// does not exist in the map, it will be added with an uninitialised value.
func (c *compiler) mapLookup(m *LLVMValue, key Value, insert bool) (elem *LLVMValue, notnull *LLVMValue) {
	mapType := m.Type().Underlying().(*types.Map)
	maplookup := c.NamedFunction("runtime.maplookup", "func f(t, m, k uintptr, insert bool) uintptr")
	ptrType := c.target.IntPtrType()
	args := make([]llvm.Value, 4)
	args[0] = llvm.ConstPtrToInt(c.types.ToRuntime(mapType), ptrType)
	args[1] = c.builder.CreatePtrToInt(m.LLVMValue(), ptrType, "")
	if insert {
		args[3] = llvm.ConstAllOnes(llvm.Int1Type())
	} else {
		args[3] = llvm.ConstNull(llvm.Int1Type())
	}

	if lv, islv := key.(*LLVMValue); islv && lv.pointer != nil {
		args[2] = c.builder.CreatePtrToInt(lv.pointer.LLVMValue(), ptrType, "")
	}
	if args[2].IsNil() {
		stackval := c.builder.CreateAlloca(c.types.ToLLVM(key.Type()), "")
		c.builder.CreateStore(key.LLVMValue(), stackval)
		args[2] = c.builder.CreatePtrToInt(stackval, ptrType, "")
	}

	eltPtrType := types.NewPointer(mapType.Elem())
	llvmtyp := c.types.ToLLVM(eltPtrType)
	zeroglobal := llvm.AddGlobal(c.module.Module, llvmtyp.ElementType(), "")
	zeroglobal.SetInitializer(llvm.ConstNull(llvmtyp.ElementType()))
	result := c.builder.CreateCall(maplookup, args, "")
	result = c.builder.CreateIntToPtr(result, llvmtyp, "")
	notnull_ := c.builder.CreateIsNotNull(result, "")
	result = c.builder.CreateSelect(notnull_, result, zeroglobal, "")
	value := c.NewValue(result, eltPtrType)
	return value.makePointee(), c.NewValue(notnull_, types.Typ[types.Bool])
}

// mapInsert inserts a key into a map, returning a pointer to the memory
// location for the value.
func (c *compiler) mapInsert(m *LLVMValue, key Value) *LLVMValue {
	mapType := m.Type().(*types.Map)
	mapinsert := c.module.Module.NamedFunction("runtime.mapinsert")
	ptrType := c.target.IntPtrType()
	if mapinsert.IsNil() {
		// params: dynamic type, mapptr, keyptr
		paramTypes := []llvm.Type{ptrType, ptrType, ptrType}
		funcType := llvm.FunctionType(ptrType, paramTypes, false)
		mapinsert = llvm.AddFunction(c.module.Module, "runtime.mapinsert", funcType)
	}
	args := make([]llvm.Value, 3)
	args[0] = llvm.ConstPtrToInt(c.types.ToRuntime(m.Type()), ptrType)
	args[1] = c.builder.CreatePtrToInt(m.pointer.LLVMValue(), ptrType, "")

	if lv, islv := key.(*LLVMValue); islv && lv.pointer != nil {
		args[2] = c.builder.CreatePtrToInt(lv.pointer.LLVMValue(), ptrType, "")
	}
	if args[2].IsNil() {
		// Create global constant, so we can take its address.
		global := llvm.AddGlobal(c.module.Module, c.types.ToLLVM(key.Type()), "")
		global.SetGlobalConstant(true)
		global.SetInitializer(key.LLVMValue())
		args[2] = c.builder.CreatePtrToInt(global, ptrType, "")
	}

	eltPtrType := &types.Pointer{Base: mapType.Elt}
	result := c.builder.CreateCall(mapinsert, args, "")
	result = c.builder.CreateIntToPtr(result, c.types.ToLLVM(eltPtrType), "")
	value := c.NewLLVMValue(result, eltPtrType)
	return value.makePointee()
}

func (tm *TypeMap) nameRuntimeType(n *types.Name) llvm.Value {
	underlyingRuntimeType := tm.ToRuntime(n.Underlying).Initializer()
	result := llvm.AddGlobal(tm.module, underlyingRuntimeType.Type(), "")
	result.SetName("__llgo.reflect." + n.Obj.Name)
	elementTypes := tm.runtimeCommonType.StructElementTypes()
	ptr := llvm.ConstBitCast(result, elementTypes[9])
	commonType := llvm.ConstInsertValue(underlyingRuntimeType, ptr, []uint32{9})

	uncommonTypeInit := llvm.ConstNull(tm.runtimeUncommonType) // TODO
	uncommonType := llvm.AddGlobal(tm.module, uncommonTypeInit.Type(), "")
	uncommonType.SetInitializer(uncommonTypeInit)
	commonType = llvm.ConstInsertValue(commonType, uncommonType, []uint32{8})

	// TODO set string, uncommonType.
	result.SetInitializer(commonType)
	return result
}

func (tm *TypeMap) basicRuntimeType(b *types.Basic) llvm.Value {
	commonType := tm.makeCommonType(b, reflect.Kind(b.Kind))
	result := llvm.AddGlobal(tm.module, commonType.Type(), "")
	elementTypes := tm.runtimeCommonType.StructElementTypes()
	ptr := llvm.ConstBitCast(result, elementTypes[9])
	commonType = llvm.ConstInsertValue(commonType, ptr, []uint32{9})
	result.SetInitializer(commonType)
	return result
}

func (c *compiler) Resolve(ident *ast.Ident) Value {
	obj := c.typeinfo.Objects[ident]
	data := c.objectdata[obj]
	if data.Value != nil {
		return data.Value
	}

	var value *LLVMValue
	switch obj := obj.(type) {
	case *types.Func:
		value = c.makeFunc(ident, obj.Type().(*types.Signature))
	case *synthFunc:
		value = c.makeFunc(ident, obj.Type().(*types.Signature))

	case *types.Var:
		if data.Ident.Obj != nil {
			switch decl := data.Ident.Obj.Decl.(type) {
			case *ast.ValueSpec:
				c.VisitValueSpec(decl)
			case *ast.Field:
				// No-op. Fields will be yielded for function
				// arg/recv/ret. We update the .Data field of the
				// object when we enter the function definition.
				if data.Value == nil {
					panic("expected object value")
				}
			}
		}

		// If it's an external variable, we'll need to create a global
		// value reference here. It may be possible for multiple objects
		// to refer to the same variable.
		value = data.Value
		if value == nil {
			module := c.module.Module
			t := obj.Type()
			name := obj.Pkg().Path() + "." + obj.Name()
			g := module.NamedGlobal(name)
			if g.IsNil() {
				g = llvm.AddGlobal(module, c.types.ToLLVM(t), name)
			}
			value = c.NewValue(g, types.NewPointer(t)).makePointee()
		}

	case *types.Const:
		value = c.NewConstValue(obj.Val(), obj.Type())

	default:
		panic(fmt.Sprintf("unreachable (%T)", obj))
	}

	data.Value = value
	return value
}

func (tm *TypeMap) mapRuntimeType(m *types.Map) llvm.Value {
	result := llvm.AddGlobal(tm.module, tm.runtimeMapType, "")
	elementTypes := tm.runtimeCommonType.StructElementTypes()
	ptr := llvm.ConstBitCast(result, elementTypes[9])
	commonType := tm.makeCommonType(m, reflect.Map)
	commonType = llvm.ConstInsertValue(commonType, ptr, []uint32{9})

	init := llvm.ConstNull(tm.runtimeMapType)
	init = llvm.ConstInsertValue(init, commonType, []uint32{0})
	result.SetInitializer(init)

	// TODO set key, elem

	return result
}

func (tm *TypeMap) structRuntimeType(s *types.Struct) llvm.Value {
	result := llvm.AddGlobal(tm.module, tm.runtimeStructType, "")
	elementTypes := tm.runtimeCommonType.StructElementTypes()
	ptr := llvm.ConstBitCast(result, elementTypes[9])
	commonType := tm.makeCommonType(s, reflect.Struct)
	commonType = llvm.ConstInsertValue(commonType, ptr, []uint32{9})

	init := llvm.ConstNull(tm.runtimeStructType)
	init = llvm.ConstInsertValue(init, commonType, []uint32{0})
	result.SetInitializer(init)

	// TODO set fields

	//panic("unimplemented")
	return result
}

func (tm *TypeMap) makeRuntimeTypeGlobal(v llvm.Value) (global, ptr llvm.Value) {
	// Each runtime type is preceded by an interface{}.
	initType := llvm.StructType([]llvm.Type{tm.runtimeType, v.Type()}, false)
	global = llvm.AddGlobal(tm.module, initType, "")
	ptr = llvm.ConstBitCast(global, llvm.PointerType(tm.runtimeType, 0))

	// interface{} containing v's *commonType representation.
	runtimeTypeValue := llvm.Undef(tm.runtimeType)
	zero := llvm.ConstNull(llvm.Int32Type())
	one := llvm.ConstInt(llvm.Int32Type(), 1, false)
	i8ptr := llvm.PointerType(llvm.Int8Type(), 0)
	if tm.commonTypePtrRuntimeType.IsNil() {
		// Create a dummy pointer value, which we'll update straight after
		// defining the runtime type info for commonType.
		tm.commonTypePtrRuntimeType = llvm.Undef(i8ptr)
		commonTypePtr := &types.Pointer{Base: tm.commonType}
		commonTypeGlobal, commonTypeRuntimeType := tm.makeRuntimeType(tm.commonType)
		tm.types[tm.commonType.String()] = runtimeTypeInfo{commonTypeGlobal, commonTypeRuntimeType}
		commonTypePtrGlobal, commonTypePtrRuntimeType := tm.makeRuntimeType(commonTypePtr)
		tm.types[commonTypePtr.String()] = runtimeTypeInfo{commonTypePtrGlobal, commonTypePtrRuntimeType}
		tm.commonTypePtrRuntimeType = llvm.ConstBitCast(commonTypePtrRuntimeType, i8ptr)
		if tm.pkgpath == tm.commonType.Package {
			// Update the interace{} header of the commonType/*commonType
			// runtime types we just created.
			for _, g := range [...]llvm.Value{commonTypeGlobal, commonTypePtrGlobal} {
				init := g.Initializer()
				typptr := tm.commonTypePtrRuntimeType
				runtimeTypeValue := llvm.ConstExtractValue(init, []uint32{0})
				runtimeTypeValue = llvm.ConstInsertValue(runtimeTypeValue, typptr, []uint32{0})
				init = llvm.ConstInsertValue(init, runtimeTypeValue, []uint32{0})
				g.SetInitializer(init)
			}
		}
	}
	commonTypePtr := llvm.ConstGEP(global, []llvm.Value{zero, one})
	commonTypePtr = llvm.ConstBitCast(commonTypePtr, i8ptr)
	runtimeTypeValue = llvm.ConstInsertValue(runtimeTypeValue, tm.commonTypePtrRuntimeType, []uint32{0})
	runtimeTypeValue = llvm.ConstInsertValue(runtimeTypeValue, commonTypePtr, []uint32{1})

	init := llvm.Undef(initType)
	init = llvm.ConstInsertValue(init, runtimeTypeValue, []uint32{0})
	init = llvm.ConstInsertValue(init, v, []uint32{1})
	global.SetInitializer(init)

	return global, ptr
}