interp: add test for icmp inttoptr workaround

interp/interp_test.go

@@ -13,6 +13,7 @@ func TestInterp(t *testing.T) {
 	for _, name := range []string{
 		"basic",
 		"slice-copy",
+		"consteval",
 	} {
 		name := name // make tc local to this closure
 		t.Run(name, func(t *testing.T) {

interp/testdata/consteval.ll

@@ -0,0 +1,27 @@
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64--linux"
+
+@intToPtrResult = global i8 0
+
+define void @runtime.initAll() {
+  call void @main.init()
+  ret void
+}
+
+define internal void @main.init() {
+  call void @testIntToPtr()
+  ret void
+}
+
+define internal void @testIntToPtr() {
+  %nil = icmp eq i8* inttoptr (i64 1024 to i8*), null
+  br i1 %nil, label %a, label %b
+a:
+  ; should not be reached
+  store i8 1, i8* @intToPtrResult
+  ret void
+b:
+  ; should be reached
+  store i8 2, i8* @intToPtrResult
+  ret void
+}

interp/testdata/consteval.out.ll

@@ -0,0 +1,8 @@
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64--linux"
+
+@intToPtrResult = local_unnamed_addr global i8 2
+
+define void @runtime.initAll() local_unnamed_addr {
+  ret void
+}