1 files changed, 12 insertions, 1 deletions
diff --git a/src-self-hosted/Module.zig b/src-self-hosted/Module.zig
index 82029c1e9f..dd4e8fea1e 100644
--- a/src-self-hosted/Module.zig
+++ b/src-self-hosted/Module.zig
@@ -2570,7 +2570,18 @@ pub fn analyzeIsNull(
     operand: *Inst,
     invert_logic: bool,
 ) InnerError!*Inst {
-    return self.fail(scope, src, "TODO implement analysis of isnull and isnotnull", .{});
+    if (operand.value()) |opt_val| {
+        const is_null = opt_val.isNull();
+        const bool_value = if (invert_logic) !is_null else is_null;
+        return self.constBool(scope, src, bool_value);
+    }
+    const b = try self.requireRuntimeBlock(scope, src);
+    const inst_tag: Inst.Tag = if (invert_logic) .isnonnull else .isnull;
+    return self.addUnOp(b, src, Type.initTag(.bool), inst_tag, operand);
+}
+
+pub fn analyzeIsErr(self: *Module, scope: *Scope, src: usize, operand: *Inst) InnerError!*Inst {
+    return self.fail(scope, src, "TODO implement analysis of iserr", .{});
 }
 
 /// Asserts that lhs and rhs types are both numeric.