Test for self-referring assignment.

2 files changed, 9 insertions, 2 deletions

diff --git a/libjulia/optimiser/DataFlowAnalyzer.cpp b/libjulia/optimiser/DataFlowAnalyzer.cpp
index 9ee3215d..56653393 100644
--- a/libjulia/optimiser/DataFlowAnalyzer.cpp
+++ b/libjulia/optimiser/DataFlowAnalyzer.cpp
@@ -135,9 +135,7 @@ void DataFlowAnalyzer::handleAssignment(set<string> const& _variables, Expressio
 		string const& name = *_variables.begin();
 		// Expression has to be movable and cannot contain a reference
 		// to the variable that will be assigned to.
-		// TODO: Add a test for that
 		if (_value && movableChecker.movable() && !movableChecker.referencedVariables().count(name))
-			// TODO If _value is null, we could use zero.
 			m_value[name] = _value;
 	}
 
diff --git a/test/libjulia/Rematerialiser.cpp b/test/libjulia/Rematerialiser.cpp
index 5bd69236..8f928f8e 100644
--- a/test/libjulia/Rematerialiser.cpp
+++ b/test/libjulia/Rematerialiser.cpp
@@ -146,6 +146,15 @@ BOOST_AUTO_TEST_CASE(reassignment)
 	);
 }
 
+BOOST_AUTO_TEST_CASE(update_assignment_remat)
+{
+	// We cannot substitute `a` in `let b := a`
+	CHECK(
+		"{ let a := extcodesize(0) a := mul(a, 2) let b := a }",
+		"{ let a := extcodesize(0) a := mul(a, 2) let b := a }"
+	);
+}
+
 BOOST_AUTO_TEST_CASE(do_not_move_out_of_scope)
 {
 	// Cannot replace by `let b := x` by `let b := a` since a is out of scope.