diff --git a/cl/_testrt/map/out.ll b/cl/_testrt/map/out.ll
index 1a93ecaf..19de1043 100644
--- a/cl/_testrt/map/out.ll
+++ b/cl/_testrt/map/out.ll
@@ -4,6 +4,8 @@ source_filename = "main"
 @"main.init$guard" = global ptr null
 @__llgo_argc = global ptr null
 @__llgo_argv = global ptr null
+@"map[_llgo_int]_llgo_int" = linkonce global ptr null
+@_llgo_int = linkonce global ptr null
 @0 = private unnamed_addr constant [10 x i8] c"Hello %d\0A\00", align 1
 
 define void @main.init() {
@@ -13,6 +15,7 @@ _llgo_0:
 
 _llgo_1:                                          ; preds = %_llgo_0
   store i1 true, ptr @"main.init$guard", align 1
+  call void @"main.init$after"()
   br label %_llgo_2
 
 _llgo_2:                                          ; preds = %_llgo_1, %_llgo_0
@@ -26,7 +29,13 @@ _llgo_0:
   call void @"github.com/goplus/llgo/internal/runtime.init"()
   call void @main.init()
   %2 = call ptr @"github.com/goplus/llgo/internal/runtime.MakeSmallMap"()
-  %3 = call i32 (ptr, ...) @printf(ptr @0, <null operand!>)
+  %3 = load ptr, ptr @"map[_llgo_int]_llgo_int", align 8
+  %4 = call ptr @"github.com/goplus/llgo/internal/runtime.MapAssign"(ptr %3, ptr %2, i64 23)
+  store i64 100, ptr %4, align 4
+  %5 = load ptr, ptr @"map[_llgo_int]_llgo_int", align 8
+  %6 = call ptr @"github.com/goplus/llgo/internal/runtime.MapAssign"(ptr %5, ptr %2, i64 7)
+  store i64 29, ptr %6, align 4
+  %7 = call i32 (ptr, ...) @printf(ptr @0, <null operand!>)
   ret i32 0
 }
 
@@ -34,4 +43,37 @@ declare void @"github.com/goplus/llgo/internal/runtime.init"()
 
 declare ptr @"github.com/goplus/llgo/internal/runtime.MakeSmallMap"()
 
+define void @"main.init$after"() {
+_llgo_0:
+  %0 = load ptr, ptr @_llgo_int, align 8
+  %1 = icmp eq ptr %0, null
+  br i1 %1, label %_llgo_1, label %_llgo_2
+
+_llgo_1:                                          ; preds = %_llgo_0
+  %2 = call ptr @"github.com/goplus/llgo/internal/runtime.Basic"(i64 2)
+  store ptr %2, ptr @_llgo_int, align 8
+  br label %_llgo_2
+
+_llgo_2:                                          ; preds = %_llgo_1, %_llgo_0
+  %3 = load ptr, ptr @_llgo_int, align 8
+  %4 = load ptr, ptr @_llgo_int, align 8
+  %5 = load ptr, ptr @"map[_llgo_int]_llgo_int", align 8
+  %6 = icmp eq ptr %5, null
+  br i1 %6, label %_llgo_3, label %_llgo_4
+
+_llgo_3:                                          ; preds = %_llgo_2
+  %7 = call ptr @"github.com/goplus/llgo/internal/runtime.MapOf"(ptr %3, ptr %4)
+  store ptr %7, ptr @"map[_llgo_int]_llgo_int", align 8
+  br label %_llgo_4
+
+_llgo_4:                                          ; preds = %_llgo_3, %_llgo_2
+  ret void
+}
+
+declare ptr @"github.com/goplus/llgo/internal/runtime.Basic"(i64)
+
+declare ptr @"github.com/goplus/llgo/internal/runtime.MapOf"(ptr, ptr)
+
+declare ptr @"github.com/goplus/llgo/internal/runtime.MapAssign"(ptr, ptr, ptr)
+
 declare i32 @printf(ptr, ...)
diff --git a/internal/runtime/z_slice.go b/internal/runtime/z_slice.go
index 61c80381..3657b22c 100644
--- a/internal/runtime/z_slice.go
+++ b/internal/runtime/z_slice.go
@@ -24,10 +24,10 @@ import (
 
 // -----------------------------------------------------------------------------
 
-// Slice is the runtime representation of a slice.
-type Slice = slice
+// type Slice = slice
 
-type slice struct {
+// Slice is the runtime representation of a slice.
+type Slice struct {
 	data unsafe.Pointer
 	len  int
 	cap  int
diff --git a/ssa/abi/abi.go b/ssa/abi/abi.go
index 4841b895..28e065b3 100644
--- a/ssa/abi/abi.go
+++ b/ssa/abi/abi.go
@@ -159,6 +159,10 @@ func (b *Builder) TypeName(t types.Type) (ret string, pub bool) {
 			return "_llgo_any", true
 		}
 		return b.InterfaceName(t)
+	case *types.Map:
+		key, pub1 := b.TypeName(t.Key())
+		elem, pub2 := b.TypeName(t.Elem())
+		return fmt.Sprintf("map[%s]%s", key, elem), pub1 && pub2
 	}
 	log.Panicf("todo: %T\n", t)
 	return
diff --git a/ssa/abitype.go b/ssa/abitype.go
index 36c14489..da29c957 100644
--- a/ssa/abitype.go
+++ b/ssa/abitype.go
@@ -66,6 +66,8 @@ func (b Builder) abiTypeOf(t types.Type) func() Expr {
 		return b.abiFuncOf(t)
 	case *types.Slice:
 		return b.abiSliceOf(t)
+	case *types.Map:
+		return b.abiMapOf(t)
 	case *types.Array:
 		return b.abiArrayOf(t)
 	}
@@ -244,6 +246,14 @@ func (b Builder) abiPointerOf(t *types.Pointer) func() Expr {
 	}
 }
 
+func (b Builder) abiMapOf(t *types.Map) func() Expr {
+	key := b.abiType(t.Key())
+	elem := b.abiType(t.Elem())
+	return func() Expr {
+		return b.Call(b.Pkg.rtFunc("MapOf"), key, elem)
+	}
+}
+
 func (b Builder) abiSliceOf(t *types.Slice) func() Expr {
 	elem := b.abiType(t.Elem())
 	return func() Expr {
diff --git a/ssa/datastruct.go b/ssa/datastruct.go
index 9981ca8f..0070e160 100644
--- a/ssa/datastruct.go
+++ b/ssa/datastruct.go
@@ -365,7 +365,9 @@ func (b Builder) MapUpdate(m, k, v Expr) {
 		panic("TODO: not a map")
 	}
 	tabi := b.abiType(t.raw.Type)
-	ptr := b.InlineCall(b.Pkg.rtFunc("MapAssign"), tabi, m, k)
+	prog := b.Prog
+	ptrimpl := b.InlineCall(b.Pkg.rtFunc("MapAssign"), tabi, m, k).impl
+	ptr := Expr{ptrimpl, prog.Pointer(v.Type)}
 	b.Store(ptr, v) // TODO(xsw): indirect store
 }