Merge pull request llir#72 from llir/type-check-store

Type check NewStore operands

Author: mewmew

ir/inst_memory.go

@@ -209,6 +209,14 @@ type InstStore struct {
 // NewStore returns a new store instruction based on the given source value and
 // destination address.
 func NewStore(src, dst value.Value) *InstStore {
+	// Type-check operands.
+	dstPtrType, ok := dst.Type().(*types.PointerType)
+	if !ok {
+		panic(fmt.Errorf("invalid store dst operand type; expected *types.Pointer, got %T", dst.Type()))
+	}
+	if !src.Type().Equal(dstPtrType.ElemType) {
+		panic(fmt.Errorf("store operands are not compatible: src=%v; dst=%v", src.Type(), dst.Type()))
+	}
 	return &InstStore{Src: src, Dst: dst}
 }
 

ir/inst_memory_test.go

@@ -0,0 +1,46 @@
+package ir
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/llir/llvm/ir/constant"
+	"github.com/llir/llvm/ir/types"
+	"github.com/pkg/errors"
+)
+
+func TestTypeCheckStore(t *testing.T) {
+	cases := []struct {
+		fromTyp, toTyp types.Type
+		panicMessage   string // "OK" if not panic'ing.
+	}{
+		{types.I8, types.I8Ptr,
+			"OK"},
+
+		{types.I64, types.I8Ptr,
+			"store operands are not compatible: src=i64; dst=i8*"},
+		{types.I8, types.I8,
+			"invalid store dst operand type; expected *types.Pointer, got *types.IntType"},
+	}
+
+	errOK := errors.New("OK")
+
+	for _, c := range cases {
+		testName := fmt.Sprintf("%v to %v", c.fromTyp, c.toTyp)
+		t.Run(testName, func(t *testing.T) {
+			var panicErr error
+			fromVal := constant.NewZeroInitializer(c.fromTyp)
+			toVal := constant.NewZeroInitializer(c.toTyp)
+			func() {
+				defer func() { panicErr = recover().(error) }()
+				store := NewStore(fromVal, toVal)
+				_ = store.LLString()
+				panic(errOK)
+			}()
+			got := panicErr.Error()
+			if got != c.panicMessage {
+				t.Errorf("expected %q, got %q", c.panicMessage, got)
+			}
+		})
+	}
+}