ssa: fix typeAssert for Nil

cl/_testgo/ifaceconv/in.go

@@ -0,0 +1,85 @@
+package main
+
+// Tests of interface conversions and type assertions.
+
+type I0 interface {
+}
+type I1 interface {
+	f()
+}
+type I2 interface {
+	f()
+	g()
+}
+
+type C0 struct{}
+type C1 struct{}
+
+func (C1) f() {}
+
+type C2 struct{}
+
+func (C2) f() {}
+func (C2) g() {}
+
+func main() {
+	var i0 I0
+	var i1 I1
+	var i2 I2
+
+	// Nil always causes a type assertion to fail, even to the
+	// same type.
+	if _, ok := i0.(I0); ok {
+		panic("nil i0.(I0) succeeded")
+	}
+	if _, ok := i1.(I1); ok {
+		panic("nil i1.(I1) succeeded")
+	}
+	if _, ok := i2.(I2); ok {
+		panic("nil i2.(I2) succeeded")
+	}
+
+	// Conversions can't fail, even with nil.
+	_ = I0(i0)
+
+	_ = I0(i1)
+	_ = I1(i1)
+
+	_ = I0(i2)
+	_ = I1(i2)
+	_ = I2(i2)
+
+	// Non-nil type assertions pass or fail based on the concrete type.
+	i1 = C1{}
+	if _, ok := i1.(I0); !ok {
+		panic("C1 i1.(I0) failed")
+	}
+	if _, ok := i1.(I1); !ok {
+		panic("C1 i1.(I1) failed")
+	}
+	if _, ok := i1.(I2); ok {
+		panic("C1 i1.(I2) succeeded")
+	}
+
+	i1 = C2{}
+	if _, ok := i1.(I0); !ok {
+		panic("C2 i1.(I0) failed")
+	}
+	if _, ok := i1.(I1); !ok {
+		panic("C2 i1.(I1) failed")
+	}
+	if _, ok := i1.(I2); !ok {
+		panic("C2 i1.(I2) failed")
+	}
+
+	// Conversions can't fail.
+	i1 = C1{}
+	if I0(i1) == nil {
+		panic("C1 I0(i1) was nil")
+	}
+	if I1(i1) == nil {
+		panic("C1 I1(i1) was nil")
+	}
+
+	println("pass")
+}

cl/_testgo/ifaceprom/in.go

@@ -0,0 +1,60 @@
+package main
+
+// Test of promotion of methods of an interface embedded within a
+// struct.  In particular, this test exercises that the correct
+// method is called.
+
+type I interface {
+	one() int
+	two() string
+}
+
+type S struct {
+	I
+}
+
+type impl struct{}
+
+func (impl) one() int {
+	return 1
+}
+
+func (impl) two() string {
+	return "two"
+}
+
+func main() {
+	var s S
+	s.I = impl{}
+	if one := s.I.one(); one != 1 {
+		panic(one)
+	}
+	if one := s.one(); one != 1 {
+		panic(one)
+	}
+	closOne := s.I.one
+	if one := closOne(); one != 1 {
+		panic(one)
+	}
+	closOne = s.one
+	if one := closOne(); one != 1 {
+		panic(one)
+	}
+
+	if two := s.I.two(); two != "two" {
+		panic(two)
+	}
+	if two := s.two(); two != "two" {
+		panic(two)
+	}
+	closTwo := s.I.two
+	if two := closTwo(); two != "two" {
+		panic(two)
+	}
+	closTwo = s.two
+	if two := closTwo(); two != "two" {
+		panic(two)
+	}
+
+	println("pass")
+}

cl/_testgo/invoke/out.ll

@@ -376,90 +376,91 @@ _llgo_1:                                          ; preds = %_llgo_0
   call void @main.invoke(%"github.com/goplus/llgo/internal/runtime.iface" %118)
   %119 = extractvalue %"github.com/goplus/llgo/internal/runtime.eface" %108, 0
   %120 = load ptr, ptr @_llgo_any, align 8
-  br i1 true, label %_llgo_3, label %_llgo_4
+  %121 = call i1 @"github.com/goplus/llgo/internal/runtime.Implements"(ptr %120, ptr %119)
+  br i1 %121, label %_llgo_3, label %_llgo_4
 
 _llgo_2:                                          ; preds = %_llgo_0
-  %121 = alloca %"github.com/goplus/llgo/internal/runtime.String", align 8
+  %122 = alloca %"github.com/goplus/llgo/internal/runtime.String", align 8
-  %122 = getelementptr inbounds %"github.com/goplus/llgo/internal/runtime.String", ptr %121, i32 0, i32 0
+  %123 = getelementptr inbounds %"github.com/goplus/llgo/internal/runtime.String", ptr %122, i32 0, i32 0
-  store ptr @32, ptr %122, align 8
+  store ptr @32, ptr %123, align 8
-  %123 = getelementptr inbounds %"github.com/goplus/llgo/internal/runtime.String", ptr %121, i32 0, i32 1
+  %124 = getelementptr inbounds %"github.com/goplus/llgo/internal/runtime.String", ptr %122, i32 0, i32 1
-  store i64 21, ptr %123, align 4
+  store i64 21, ptr %124, align 4
-  %124 = load %"github.com/goplus/llgo/internal/runtime.String", ptr %121, align 8
+  %125 = load %"github.com/goplus/llgo/internal/runtime.String", ptr %122, align 8
-  %125 = load ptr, ptr @_llgo_string, align 8
+  %126 = load ptr, ptr @_llgo_string, align 8
-  %126 = call ptr @"github.com/goplus/llgo/internal/runtime.AllocU"(i64 16)
+  %127 = call ptr @"github.com/goplus/llgo/internal/runtime.AllocU"(i64 16)
-  store %"github.com/goplus/llgo/internal/runtime.String" %124, ptr %126, align 8
+  store %"github.com/goplus/llgo/internal/runtime.String" %125, ptr %127, align 8
-  %127 = alloca %"github.com/goplus/llgo/internal/runtime.eface", align 8
+  %128 = alloca %"github.com/goplus/llgo/internal/runtime.eface", align 8
-  %128 = getelementptr inbounds %"github.com/goplus/llgo/internal/runtime.eface", ptr %127, i32 0, i32 0
+  %129 = getelementptr inbounds %"github.com/goplus/llgo/internal/runtime.eface", ptr %128, i32 0, i32 0
-  store ptr %125, ptr %128, align 8
-  %129 = getelementptr inbounds %"github.com/goplus/llgo/internal/runtime.eface", ptr %127, i32 0, i32 1
   store ptr %126, ptr %129, align 8
-  %130 = load %"github.com/goplus/llgo/internal/runtime.eface", ptr %127, align 8
+  %130 = getelementptr inbounds %"github.com/goplus/llgo/internal/runtime.eface", ptr %128, i32 0, i32 1
-  call void @"github.com/goplus/llgo/internal/runtime.TracePanic"(%"github.com/goplus/llgo/internal/runtime.eface" %130)
+  store ptr %127, ptr %130, align 8
+  %131 = load %"github.com/goplus/llgo/internal/runtime.eface", ptr %128, align 8
+  call void @"github.com/goplus/llgo/internal/runtime.TracePanic"(%"github.com/goplus/llgo/internal/runtime.eface" %131)
   unreachable
 
 _llgo_3:                                          ; preds = %_llgo_1
-  %131 = extractvalue %"github.com/goplus/llgo/internal/runtime.eface" %108, 1
+  %132 = extractvalue %"github.com/goplus/llgo/internal/runtime.eface" %108, 1
-  %132 = alloca %"github.com/goplus/llgo/internal/runtime.eface", align 8
+  %133 = alloca %"github.com/goplus/llgo/internal/runtime.eface", align 8
-  %133 = getelementptr inbounds %"github.com/goplus/llgo/internal/runtime.eface", ptr %132, i32 0, i32 0
+  %134 = getelementptr inbounds %"github.com/goplus/llgo/internal/runtime.eface", ptr %133, i32 0, i32 0
-  store ptr %119, ptr %133, align 8
+  store ptr %119, ptr %134, align 8
-  %134 = getelementptr inbounds %"github.com/goplus/llgo/internal/runtime.eface", ptr %132, i32 0, i32 1
+  %135 = getelementptr inbounds %"github.com/goplus/llgo/internal/runtime.eface", ptr %133, i32 0, i32 1
-  store ptr %131, ptr %134, align 8
+  store ptr %132, ptr %135, align 8
-  %135 = load %"github.com/goplus/llgo/internal/runtime.eface", ptr %132, align 8
+  %136 = load %"github.com/goplus/llgo/internal/runtime.eface", ptr %133, align 8
-  %136 = extractvalue %"github.com/goplus/llgo/internal/runtime.eface" %135, 0
+  %137 = extractvalue %"github.com/goplus/llgo/internal/runtime.eface" %136, 0
-  %137 = load ptr, ptr @"_llgo_iface$uRUteI7wmSy7y7ODhGzk0FdDaxGKMhVSSu6HZEv9aa0", align 8
+  %138 = load ptr, ptr @"_llgo_iface$uRUteI7wmSy7y7ODhGzk0FdDaxGKMhVSSu6HZEv9aa0", align 8
-  %138 = call i1 @"github.com/goplus/llgo/internal/runtime.Implements"(ptr %137, ptr %136)
+  %139 = call i1 @"github.com/goplus/llgo/internal/runtime.Implements"(ptr %138, ptr %137)
-  br i1 %138, label %_llgo_5, label %_llgo_6
+  br i1 %139, label %_llgo_5, label %_llgo_6
 
 _llgo_4:                                          ; preds = %_llgo_1
-  %139 = alloca %"github.com/goplus/llgo/internal/runtime.String", align 8
+  %140 = alloca %"github.com/goplus/llgo/internal/runtime.String", align 8
-  %140 = getelementptr inbounds %"github.com/goplus/llgo/internal/runtime.String", ptr %139, i32 0, i32 0
+  %141 = getelementptr inbounds %"github.com/goplus/llgo/internal/runtime.String", ptr %140, i32 0, i32 0
-  store ptr @35, ptr %140, align 8
+  store ptr @35, ptr %141, align 8
-  %141 = getelementptr inbounds %"github.com/goplus/llgo/internal/runtime.String", ptr %139, i32 0, i32 1
+  %142 = getelementptr inbounds %"github.com/goplus/llgo/internal/runtime.String", ptr %140, i32 0, i32 1
-  store i64 21, ptr %141, align 4
+  store i64 21, ptr %142, align 4
-  %142 = load %"github.com/goplus/llgo/internal/runtime.String", ptr %139, align 8
+  %143 = load %"github.com/goplus/llgo/internal/runtime.String", ptr %140, align 8
-  %143 = load ptr, ptr @_llgo_string, align 8
+  %144 = load ptr, ptr @_llgo_string, align 8
-  %144 = call ptr @"github.com/goplus/llgo/internal/runtime.AllocU"(i64 16)
+  %145 = call ptr @"github.com/goplus/llgo/internal/runtime.AllocU"(i64 16)
-  store %"github.com/goplus/llgo/internal/runtime.String" %142, ptr %144, align 8
+  store %"github.com/goplus/llgo/internal/runtime.String" %143, ptr %145, align 8
-  %145 = alloca %"github.com/goplus/llgo/internal/runtime.eface", align 8
+  %146 = alloca %"github.com/goplus/llgo/internal/runtime.eface", align 8
-  %146 = getelementptr inbounds %"github.com/goplus/llgo/internal/runtime.eface", ptr %145, i32 0, i32 0
+  %147 = getelementptr inbounds %"github.com/goplus/llgo/internal/runtime.eface", ptr %146, i32 0, i32 0
-  store ptr %143, ptr %146, align 8
-  %147 = getelementptr inbounds %"github.com/goplus/llgo/internal/runtime.eface", ptr %145, i32 0, i32 1
   store ptr %144, ptr %147, align 8
-  %148 = load %"github.com/goplus/llgo/internal/runtime.eface", ptr %145, align 8
+  %148 = getelementptr inbounds %"github.com/goplus/llgo/internal/runtime.eface", ptr %146, i32 0, i32 1
-  call void @"github.com/goplus/llgo/internal/runtime.TracePanic"(%"github.com/goplus/llgo/internal/runtime.eface" %148)
+  store ptr %145, ptr %148, align 8
+  %149 = load %"github.com/goplus/llgo/internal/runtime.eface", ptr %146, align 8
+  call void @"github.com/goplus/llgo/internal/runtime.TracePanic"(%"github.com/goplus/llgo/internal/runtime.eface" %149)
   unreachable
 
 _llgo_5:                                          ; preds = %_llgo_3
-  %149 = extractvalue %"github.com/goplus/llgo/internal/runtime.eface" %135, 1
+  %150 = extractvalue %"github.com/goplus/llgo/internal/runtime.eface" %136, 1
-  %150 = load ptr, ptr @"_llgo_iface$uRUteI7wmSy7y7ODhGzk0FdDaxGKMhVSSu6HZEv9aa0", align 8
+  %151 = load ptr, ptr @"_llgo_iface$uRUteI7wmSy7y7ODhGzk0FdDaxGKMhVSSu6HZEv9aa0", align 8
-  %151 = call ptr @"github.com/goplus/llgo/internal/runtime.NewItab"(ptr %150, ptr %136)
+  %152 = call ptr @"github.com/goplus/llgo/internal/runtime.NewItab"(ptr %151, ptr %137)
-  %152 = alloca %"github.com/goplus/llgo/internal/runtime.iface", align 8
+  %153 = alloca %"github.com/goplus/llgo/internal/runtime.iface", align 8
-  %153 = getelementptr inbounds %"github.com/goplus/llgo/internal/runtime.iface", ptr %152, i32 0, i32 0
+  %154 = getelementptr inbounds %"github.com/goplus/llgo/internal/runtime.iface", ptr %153, i32 0, i32 0
-  store ptr %151, ptr %153, align 8
+  store ptr %152, ptr %154, align 8
-  %154 = getelementptr inbounds %"github.com/goplus/llgo/internal/runtime.iface", ptr %152, i32 0, i32 1
+  %155 = getelementptr inbounds %"github.com/goplus/llgo/internal/runtime.iface", ptr %153, i32 0, i32 1
-  store ptr %149, ptr %154, align 8
+  store ptr %150, ptr %155, align 8
-  %155 = load %"github.com/goplus/llgo/internal/runtime.iface", ptr %152, align 8
+  %156 = load %"github.com/goplus/llgo/internal/runtime.iface", ptr %153, align 8
-  call void @main.invoke(%"github.com/goplus/llgo/internal/runtime.iface" %155)
+  call void @main.invoke(%"github.com/goplus/llgo/internal/runtime.iface" %156)
   call void @main.invoke(%"github.com/goplus/llgo/internal/runtime.iface" zeroinitializer)
   ret i32 0
 
 _llgo_6:                                          ; preds = %_llgo_3
-  %156 = alloca %"github.com/goplus/llgo/internal/runtime.String", align 8
+  %157 = alloca %"github.com/goplus/llgo/internal/runtime.String", align 8
-  %157 = getelementptr inbounds %"github.com/goplus/llgo/internal/runtime.String", ptr %156, i32 0, i32 0
+  %158 = getelementptr inbounds %"github.com/goplus/llgo/internal/runtime.String", ptr %157, i32 0, i32 0
-  store ptr @36, ptr %157, align 8
+  store ptr @36, ptr %158, align 8
-  %158 = getelementptr inbounds %"github.com/goplus/llgo/internal/runtime.String", ptr %156, i32 0, i32 1
+  %159 = getelementptr inbounds %"github.com/goplus/llgo/internal/runtime.String", ptr %157, i32 0, i32 1
-  store i64 21, ptr %158, align 4
+  store i64 21, ptr %159, align 4
-  %159 = load %"github.com/goplus/llgo/internal/runtime.String", ptr %156, align 8
+  %160 = load %"github.com/goplus/llgo/internal/runtime.String", ptr %157, align 8
-  %160 = load ptr, ptr @_llgo_string, align 8
+  %161 = load ptr, ptr @_llgo_string, align 8
-  %161 = call ptr @"github.com/goplus/llgo/internal/runtime.AllocU"(i64 16)
+  %162 = call ptr @"github.com/goplus/llgo/internal/runtime.AllocU"(i64 16)
-  store %"github.com/goplus/llgo/internal/runtime.String" %159, ptr %161, align 8
+  store %"github.com/goplus/llgo/internal/runtime.String" %160, ptr %162, align 8
-  %162 = alloca %"github.com/goplus/llgo/internal/runtime.eface", align 8
+  %163 = alloca %"github.com/goplus/llgo/internal/runtime.eface", align 8
-  %163 = getelementptr inbounds %"github.com/goplus/llgo/internal/runtime.eface", ptr %162, i32 0, i32 0
+  %164 = getelementptr inbounds %"github.com/goplus/llgo/internal/runtime.eface", ptr %163, i32 0, i32 0
-  store ptr %160, ptr %163, align 8
-  %164 = getelementptr inbounds %"github.com/goplus/llgo/internal/runtime.eface", ptr %162, i32 0, i32 1
   store ptr %161, ptr %164, align 8
-  %165 = load %"github.com/goplus/llgo/internal/runtime.eface", ptr %162, align 8
+  %165 = getelementptr inbounds %"github.com/goplus/llgo/internal/runtime.eface", ptr %163, i32 0, i32 1
-  call void @"github.com/goplus/llgo/internal/runtime.TracePanic"(%"github.com/goplus/llgo/internal/runtime.eface" %165)
+  store ptr %162, ptr %165, align 8
+  %166 = load %"github.com/goplus/llgo/internal/runtime.eface", ptr %163, align 8
+  call void @"github.com/goplus/llgo/internal/runtime.TracePanic"(%"github.com/goplus/llgo/internal/runtime.eface" %166)
   unreachable
 }
 

internal/runtime/z_face.go

@@ -268,6 +268,9 @@ func IfacePtrData(i iface) unsafe.Pointer {
 
 // Implements reports whether the type V implements the interface type T.
 func Implements(T, V *abi.Type) bool {
+	if V == nil {
+		return false
+	}
 	if T.Kind() != abi.Interface {
 		return false
 	}

ssa/interface.go

@@ -238,11 +238,7 @@ func (b Builder) TypeAssert(x Expr, assertedTyp Type, commaOk bool) Expr {
 	var eq Expr
 	var val func() Expr
 	if rawIntf, ok := assertedTyp.raw.Type.Underlying().(*types.Interface); ok {
-		if rawIntf.Empty() {
+		eq = b.InlineCall(b.Pkg.rtFunc("Implements"), tabi, tx)
-			eq = b.Prog.BoolVal(true)
-		} else {
-			eq = b.InlineCall(b.Pkg.rtFunc("Implements"), tabi, tx)
-		}
 		val = func() Expr { return Expr{b.unsafeInterface(rawIntf, tx, b.faceData(x.impl)), assertedTyp} }
 	} else {
 		eq = b.BinOp(token.EQL, tx, tabi)