compiler: add support for type parameters (aka generics)

...that was surprisingly easy.

compiler/compiler.go

@@ -21,6 +21,10 @@ import (
 	"tinygo.org/x/go-llvm"
 )
 
+var typeParamUnderlyingType = func(t types.Type) types.Type {
+	return t
+}
+
 func init() {
 	llvm.InitializeAllTargets()
 	llvm.InitializeAllTargetMCs()
@@ -335,6 +339,7 @@ func (c *compilerContext) getLLVMType(goType types.Type) llvm.Type {
 // makeLLVMType creates a LLVM type for a Go type. Don't call this, use
 // getLLVMType instead.
 func (c *compilerContext) makeLLVMType(goType types.Type) llvm.Type {
+	goType = typeParamUnderlyingType(goType)
 	switch typ := goType.(type) {
 	case *types.Array:
 		elemType := c.getLLVMType(typ.Elem())
@@ -444,6 +449,7 @@ func (c *compilerContext) getDIType(typ types.Type) llvm.Metadata {
 // createDIType creates a new DWARF type. Don't call this function directly,
 // call getDIType instead.
 func (c *compilerContext) createDIType(typ types.Type) llvm.Metadata {
+	typ = typeParamUnderlyingType(typ)
 	llvmType := c.getLLVMType(typ)
 	sizeInBytes := c.targetData.TypeAllocSize(llvmType)
 	switch typ := typ.(type) {
@@ -794,6 +800,9 @@ func (c *compilerContext) createPackage(irbuilder llvm.Builder, pkg *ssa.Package
 			for _, method := range methods {
 				// Parse this method.
 				fn := pkg.Prog.MethodValue(method)
+				if fn == nil {
+					continue // probably a generic method
+				}
 				if fn.Blocks == nil {
 					continue // external function
 				}

compiler/compiler_go118.go

@@ -0,0 +1,18 @@
+//go:build go1.18
+// +build go1.18
+
+package compiler
+
+// Workaround for Go 1.17 support. Should be removed once we drop Go 1.17
+// support.
+
+import "go/types"
+
+func init() {
+	typeParamUnderlyingType = func(t types.Type) types.Type {
+		if t, ok := t.(*types.TypeParam); ok {
+			return t.Underlying()
+		}
+		return t
+	}
+}

compiler/symbol.go

@@ -191,7 +191,7 @@ func (c *compilerContext) getFunction(fn *ssa.Function) llvm.Value {
 	// should be created right away.
 	// The exception is the package initializer, which does appear in the
 	// *ssa.Package members and so shouldn't be created here.
-	if fn.Synthetic != "" && fn.Synthetic != "package initializer" {
+	if fn.Synthetic != "" && fn.Synthetic != "package initializer" && fn.Synthetic != "generic function" {
 		irbuilder := c.ctx.NewBuilder()
 		b := newBuilder(c, irbuilder, fn)
 		b.createFunction()

go.mod

@@ -13,7 +13,7 @@ require (
 	github.com/mattn/go-colorable v0.1.8
 	go.bug.st/serial v1.1.3
 	golang.org/x/sys v0.0.0-20220114195835-da31bd327af9
-	golang.org/x/tools v0.1.6-0.20210813165731-45389f592fe9
+	golang.org/x/tools v0.1.11
 	gopkg.in/yaml.v2 v2.4.0
 	tinygo.org/x/go-llvm v0.0.0-20220420140351-512c94c1e71f
 )

go.sum

@@ -40,41 +40,40 @@ github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZN
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/testify v1.4.0 h1:2E4SXV/wtOkTonXsotYi4li6zVWxYlZuYNCXe9XRJyk=
 github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
-github.com/yuin/goldmark v1.3.5/go.mod h1:mwnBkeHKe2W/ZEtQ+71ViKU8L12m81fl3OWwC1Zlc8k=
+github.com/yuin/goldmark v1.4.1/go.mod h1:mwnBkeHKe2W/ZEtQ+71ViKU8L12m81fl3OWwC1Zlc8k=
 go.bug.st/serial v1.1.3 h1:YEBxJa9pKS9Wdg46B/jiaKbvvbUrjhZZZITfJHEJhaE=
 go.bug.st/serial v1.1.3/go.mod h1:8TT7u/SwwNIpJ8QaG4s+HTjFt9ReXs2cdOU7ZEk50Dk=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
-golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
+golang.org/x/crypto v0.0.0-20210921155107-089bfa567519/go.mod h1:GvvjBRRGRdwPK5ydBHafDWAxML/pGHZbMvKqRZ5+Abc=
-golang.org/x/mod v0.4.2 h1:Gz96sIWK3OalVv/I/qNygP42zyoKp3xptRVCWRFEBvo=
+golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4 h1:6zppjxzCulZykYSLyVDYbneBfbaBIQPYMevg0bEwv2s=
-golang.org/x/mod v0.4.2/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
+golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4/go.mod h1:jJ57K6gSWd91VN4djpZkiMVwK6gcyfeH4XE8wZrZaV4=
-golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
 golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
-golang.org/x/net v0.0.0-20210405180319-a5a99cb37ef4/go.mod h1:p54w0d4576C0XHj96bSt6lcn1PtDYWL6XObtHCRCNQM=
+golang.org/x/net v0.0.0-20210226172049-e18ecbb05110/go.mod h1:m0MpNAwzfU5UDzcl9v0D8zg8gWTRqZa9RBIspLL5mdg=
+golang.org/x/net v0.0.0-20211015210444-4f30a5c0130f/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
 golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20210220032951-036812b2e83c/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
-golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200116001909-b77594299b42/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200223170610-d5e6a3e2c0ae/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200909081042-eff7692f9009/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20201207223542-d4d67f95c62d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20210330210617-4fbd30eecc44/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20210423082822-04245dca01da/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20210510120138-977fb7262007/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.0.0-20210615035016-665e8c7367d1/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.0.0-20211019181941-9d821ace8654/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20211124211545-fe61309f8881/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20220114195835-da31bd327af9 h1:XfKQ4OlFl8okEOr5UvAqFRVj8pY/4yfcXrddB8qAbU0=
 golang.org/x/sys v0.0.0-20220114195835-da31bd327af9/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
+golang.org/x/text v0.3.6/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
+golang.org/x/text v0.3.7/go.mod h1:u+2+/6zg+i71rQMx5EYifcz6MCKuco9NR6JIITiCfzQ=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
 golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
-golang.org/x/tools v0.1.6-0.20210813165731-45389f592fe9 h1:nvvuMxmx1q0gfRki3T0hjG8EwAcVCs91oWAXvyt4zhI=
+golang.org/x/tools v0.1.11 h1:loJ25fNOEhSXfHrpoGj91eCUThwdNX6u24rO1xnNteY=
-golang.org/x/tools v0.1.6-0.20210813165731-45389f592fe9/go.mod h1:o0xws9oXOQQZyjljx8fwUC0k7L1pTE6eaCbjGeHmOkk=
+golang.org/x/tools v0.1.11/go.mod h1:SgwaegtQh8clINPpECJMqnxLv9I09HLqnW3RMqW0CA4=
 golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
-golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
-golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 h1:go1bK/D/BFZV2I8cIQd1NKEZ+0owSTG1fDTci4IqFcE=
-golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=

loader/loader.go

@@ -28,6 +28,8 @@ import (
 	"github.com/tinygo-org/tinygo/goenv"
 )
 
+var addInstances func(*types.Info)
+
 // Program holds all packages and some metadata about the program as a whole.
 type Program struct {
 	config       *compileopts.Config
@@ -164,6 +166,9 @@ func Load(config *compileopts.Config, inputPkg string, clangHeaders string, type
 				Selections: make(map[*ast.SelectorExpr]*types.Selection),
 			},
 		}
+		if addInstances != nil {
+			addInstances(&pkg.info)
+		}
 		err := decoder.Decode(&pkg.PackageJSON)
 		if err != nil {
 			if err == io.EOF {

loader/loader_go118.go

@@ -0,0 +1,18 @@
+//go:build go1.18
+// +build go1.18
+
+package loader
+
+// Workaround for Go 1.17 support. Should be removed once we drop Go 1.17
+// support.
+
+import (
+	"go/ast"
+	"go/types"
+)
+
+func init() {
+	addInstances = func(info *types.Info) {
+		info.Instances = make(map[*ast.Ident]types.Instance)
+	}
+}

loader/ssa.go

@@ -8,7 +8,7 @@ import (
 //
 // The program must already be parsed and type-checked with the .Parse() method.
 func (p *Program) LoadSSA() *ssa.Program {
-	prog := ssa.NewProgram(p.fset, ssa.SanityCheckFunctions|ssa.BareInits|ssa.GlobalDebug)
+	prog := ssa.NewProgram(p.fset, ssa.SanityCheckFunctions|ssa.BareInits|ssa.GlobalDebug|ssa.InstantiateGenerics)
 
 	for _, pkg := range p.sorted {
 		prog.CreatePackage(pkg.Pkg, pkg.Files, &pkg.info, true)

main_test.go

@@ -76,6 +76,7 @@ func TestBuild(t *testing.T) {
 		tests = append(tests, "go1.17.go")
 	}
 	if minor >= 18 {
+		tests = append(tests, "generics.go")
 		tests = append(tests, "testing_go118.go")
 	} else {
 		tests = append(tests, "testing.go")

testdata/generics.go

@@ -0,0 +1,14 @@
+package main
+
+func main() {
+	println("add:", Add(3, 5))
+	println("add:", Add(int8(3), 5))
+}
+
+type Integer interface {
+	int | int8 | int16 | int32 | int64
+}
+
+func Add[T Integer](a, b T) T {
+	return a + b
+}

testdata/generics.txt

@@ -0,0 +1,2 @@
+add: 8
+add: 8