Example #1
0
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
}
Example #2
0
// 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
}
Example #3
0
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.
	linkage := llvm.LinkOnceAnyLinkage
	switch elem := p.Elem().(type) {
	case *types.Basic:
		if tm.pkgpath != "runtime" {
			global := llvm.AddGlobal(tm.module, tm.runtime.rtype.llvm, typeSymbol(typeString(p)))
			global.SetInitializer(llvm.ConstNull(tm.runtime.rtype.llvm))
			global.SetLinkage(llvm.CommonLinkage)
			return global, global
		}
		linkage = llvm.ExternalLinkage
	case *types.Named:
		path := "runtime"
		if pkg := elem.Obj().Pkg(); pkg != nil {
			path = pkg.Path()
		}
		if path != tm.pkgpath {
			global := llvm.AddGlobal(tm.module, tm.runtime.rtype.llvm, typeSymbol(typeString(p)))
			global.SetInitializer(llvm.ConstNull(tm.runtime.rtype.llvm))
			global.SetLinkage(llvm.CommonLinkage)
			return global, global
		}
		linkage = llvm.ExternalLinkage
	}

	rtype := tm.makeRtype(p, reflect.Ptr)
	if n, ok := p.Elem().(*types.Named); ok {
		uncommonTypeInit := tm.uncommonType(n, p)
		uncommonType := llvm.AddGlobal(tm.module, uncommonTypeInit.Type(), "")
		uncommonType.SetInitializer(uncommonTypeInit)
		rtype = llvm.ConstInsertValue(rtype, uncommonType, []uint32{9})
	}

	ptrType := llvm.ConstNull(tm.runtime.ptrType.llvm)
	var baseTypeGlobal llvm.Value
	if p.Elem().Underlying() == p {
		// Recursive pointer.
		ptrType = llvm.ConstInsertValue(ptrType, rtype, []uint32{0})
		global, ptr = tm.makeRuntimeTypeGlobal(ptrType, typeString(p))
		baseTypeGlobal = global
		// Update the global with its own pointer in the elem field.
		ptrType = global.Initializer()
		ptrType = llvm.ConstInsertValue(ptrType, ptr, []uint32{1})
		global.SetInitializer(ptrType)
	} else {
		var baseTypePtr llvm.Value
		baseTypeGlobal, baseTypePtr = tm.toRuntime(p.Elem())
		ptrType = llvm.ConstInsertValue(ptrType, rtype, []uint32{0})
		ptrType = llvm.ConstInsertValue(ptrType, baseTypePtr, []uint32{1})
		global, ptr = tm.makeRuntimeTypeGlobal(ptrType, typeString(p))
	}
	global.SetLinkage(linkage)

	// Set ptrToThis in the base type's rtype.
	baseType := baseTypeGlobal.Initializer()
	if !baseType.IsNull() {
		if baseType.Type() == tm.runtime.rtype.llvm {
			baseType = llvm.ConstInsertValue(baseType, ptr, []uint32{10})
		} else {
			rtype := llvm.ConstExtractValue(baseType, []uint32{0})
			rtype = llvm.ConstInsertValue(rtype, ptr, []uint32{10})
			baseType = llvm.ConstInsertValue(baseType, rtype, []uint32{0})
		}
		baseTypeGlobal.SetInitializer(baseType)
	}
	return global, ptr
}