From e1b44500ddb01ad0a0c26fb541c94eea60860873 Mon Sep 17 00:00:00 2001
From: Bhargava Shastry <bhargava.shastry@ethereum.org>
Date: Wed, 22 Jul 2020 22:59:15 +0200
Subject: [PATCH] Yul interpreter: Smaller execution timeout for tests and
 additional test cases

---
 test/libyul/YulInterpreterTest.cpp            |  4 +-
 .../yulInterpreterTests/bounded_recursion.yul | 16 +++++++
 .../infinite_recursion.yul                    | 11 +++++
 .../infinite_recursion_tracelimit.yul         | 44 +++++++++++++++++++
 test/tools/ossfuzz/yulProto_diff_ossfuzz.cpp  |  8 +++-
 5 files changed, 80 insertions(+), 3 deletions(-)
 create mode 100644 test/libyul/yulInterpreterTests/bounded_recursion.yul
 create mode 100644 test/libyul/yulInterpreterTests/infinite_recursion.yul
 create mode 100644 test/libyul/yulInterpreterTests/infinite_recursion_tracelimit.yul

diff --git a/test/libyul/YulInterpreterTest.cpp b/test/libyul/YulInterpreterTest.cpp
index 78e815785..ec1fa53f1 100644
--- a/test/libyul/YulInterpreterTest.cpp
+++ b/test/libyul/YulInterpreterTest.cpp
@@ -87,8 +87,8 @@ bool YulInterpreterTest::parse(ostream& _stream, string const& _linePrefix, bool
 string YulInterpreterTest::interpret()
 {
 	InterpreterState state;
-	state.maxTraceSize = 10000;
-	state.maxSteps = 10000;
+	state.maxTraceSize = 32;
+	state.maxSteps = 512;
 	try
 	{
 		Interpreter::run(state, EVMDialect::strictAssemblyForEVMObjects(langutil::EVMVersion{}), *m_ast);
diff --git a/test/libyul/yulInterpreterTests/bounded_recursion.yul b/test/libyul/yulInterpreterTests/bounded_recursion.yul
new file mode 100644
index 000000000..ce22638ca
--- /dev/null
+++ b/test/libyul/yulInterpreterTests/bounded_recursion.yul
@@ -0,0 +1,16 @@
+{
+  function f(x) -> y {
+    if lt(x, 150) {
+      y := f(add(x, 1))
+    }
+    if eq(x, 150) {
+      y := x
+    }
+  }
+  mstore(0, f(0))
+}
+// ----
+// Trace:
+// Memory dump:
+//      0: 0000000000000000000000000000000000000000000000000000000000000096
+// Storage dump:
diff --git a/test/libyul/yulInterpreterTests/infinite_recursion.yul b/test/libyul/yulInterpreterTests/infinite_recursion.yul
new file mode 100644
index 000000000..0e3109ab5
--- /dev/null
+++ b/test/libyul/yulInterpreterTests/infinite_recursion.yul
@@ -0,0 +1,11 @@
+{
+  function f() {
+    f()
+  }
+  f()
+}
+// ----
+// Trace:
+//   Interpreter execution step limit reached.
+// Memory dump:
+// Storage dump:
diff --git a/test/libyul/yulInterpreterTests/infinite_recursion_tracelimit.yul b/test/libyul/yulInterpreterTests/infinite_recursion_tracelimit.yul
new file mode 100644
index 000000000..45d3cc781
--- /dev/null
+++ b/test/libyul/yulInterpreterTests/infinite_recursion_tracelimit.yul
@@ -0,0 +1,44 @@
+{
+  function f() {
+    log0(0x0, 0x0)
+    f()
+  }
+  f()
+}
+// ----
+// Trace:
+//   LOG0(0, 0)
+//   LOG0(0, 0)
+//   LOG0(0, 0)
+//   LOG0(0, 0)
+//   LOG0(0, 0)
+//   LOG0(0, 0)
+//   LOG0(0, 0)
+//   LOG0(0, 0)
+//   LOG0(0, 0)
+//   LOG0(0, 0)
+//   LOG0(0, 0)
+//   LOG0(0, 0)
+//   LOG0(0, 0)
+//   LOG0(0, 0)
+//   LOG0(0, 0)
+//   LOG0(0, 0)
+//   LOG0(0, 0)
+//   LOG0(0, 0)
+//   LOG0(0, 0)
+//   LOG0(0, 0)
+//   LOG0(0, 0)
+//   LOG0(0, 0)
+//   LOG0(0, 0)
+//   LOG0(0, 0)
+//   LOG0(0, 0)
+//   LOG0(0, 0)
+//   LOG0(0, 0)
+//   LOG0(0, 0)
+//   LOG0(0, 0)
+//   LOG0(0, 0)
+//   LOG0(0, 0)
+//   LOG0(0, 0)
+//   Trace size limit reached.
+// Memory dump:
+// Storage dump:
diff --git a/test/tools/ossfuzz/yulProto_diff_ossfuzz.cpp b/test/tools/ossfuzz/yulProto_diff_ossfuzz.cpp
index c95b4db7f..de9bfe9c7 100644
--- a/test/tools/ossfuzz/yulProto_diff_ossfuzz.cpp
+++ b/test/tools/ossfuzz/yulProto_diff_ossfuzz.cpp
@@ -104,12 +104,18 @@ DEFINE_PROTO_FUZZER(Program const& _input)
 		return;
 
 	stack.optimize();
-	yulFuzzerUtil::interpret(
+	termReason = yulFuzzerUtil::interpret(
 		os2,
 		stack.parserResult()->code,
 		EVMDialect::strictAssemblyForEVMObjects(version)
 	);
 
+	if (
+		termReason == yulFuzzerUtil::TerminationReason::StepLimitReached ||
+		termReason == yulFuzzerUtil::TerminationReason::TraceLimitReached
+	)
+		return;
+
 	bool isTraceEq = (os1.str() == os2.str());
 	yulAssert(isTraceEq, "Interpreted traces for optimized and unoptimized code differ.");
 	return;