[SMTChecker] Support modifiers

test/libsolidity/smtCheckerTests/modifiers/modifier_code_after_placeholder.sol

@@ -0,0 +1,22 @@
+pragma experimental SMTChecker;
+
+contract C
+{
+	uint x;
+
+	modifier m {
+		require(x > 0);
+		_;
+		// Fails because of overflow behavior.
+		// Overflow is not reported because this assertion prevents
+		// it from reaching the end of the function.
+		assert(x > 1);
+	}
+
+	function f() m public {
+		assert(x > 0);
+		x = x + 1;
+	}
+}
+// ----
+// Warning: (245-258): Assertion violation happens here

test/libsolidity/smtCheckerTests/modifiers/modifier_control_flow.sol

@@ -0,0 +1,18 @@
+pragma experimental SMTChecker;
+
+contract C
+{
+	uint x;
+
+	modifier m {
+		if (x == 0)
+			_;
+	}
+
+	function f() m public view {
+		assert(x == 0);
+		assert(x > 1);
+	}
+}
+// ----
+// Warning: (144-157): Assertion violation happens here

test/libsolidity/smtCheckerTests/modifiers/modifier_multi.sol

@@ -0,0 +1,25 @@
+pragma experimental SMTChecker;
+
+contract C
+{
+	uint x;
+
+	modifier m {
+		require(x > 0);
+		require(x < 10000);
+		_;
+	}
+
+	modifier n {
+		x = x + 1;
+		_;
+		assert(x > 2);
+		assert(x > 8);
+	}
+
+	function f() m n public {
+		x = x + 1;
+	}
+}
+// ----
+// Warning: (170-183): Assertion violation happens here

test/libsolidity/smtCheckerTests/modifiers/modifier_multi_functions.sol

@@ -0,0 +1,26 @@
+pragma experimental SMTChecker;
+
+contract C
+{
+	modifier m(uint a, uint b) {
+		require(g(a, b));
+		_;
+	}
+
+	modifier notZero(uint x) {
+		require(x > 0);
+		_;
+	}
+
+	function g(uint a, uint b) notZero(a) internal pure returns (bool) {
+		return a > b;
+	}
+
+	function f(uint x) m(x, 0) public pure {
+		assert(x > 0);
+		assert(x > 1);
+	}
+}
+// ----
+// Warning: (86-93): Condition is always true.
+// Warning: (311-324): Assertion violation happens here

test/libsolidity/smtCheckerTests/modifiers/modifier_multi_functions_recursive.sol

@@ -0,0 +1,24 @@
+pragma experimental SMTChecker;
+
+contract C
+{
+	modifier m(uint a, uint b) {
+		require(g(a, b));
+		_;
+	}
+
+	function g(uint a, uint b) m(a, b) internal pure returns (bool) {
+		return a > b;
+	}
+
+	function f(uint x) m(x, 0) public pure {
+		assert(x > 0);
+		assert(x > 1);
+	}
+}
+// ----
+// Warning: (86-93): Assertion checker does not support recursive function calls.
+// Warning: (86-93): Internal error: Expression undefined for SMT solver.
+// Warning: (86-93): Assertion checker does not support recursive function calls.
+// Warning: (86-93): Internal error: Expression undefined for SMT solver.
+// Warning: (253-266): Assertion violation happens here

test/libsolidity/smtCheckerTests/modifiers/modifier_multi_parameters.sol

@@ -0,0 +1,16 @@
+pragma experimental SMTChecker;
+
+contract C
+{
+	modifier m(uint a, uint b) {
+		require(a > b);
+		_;
+	}
+
+	function f(uint x) m(x, 0) public pure {
+		assert(x > 0);
+		assert(x > 1);
+	}
+}
+// ----
+// Warning: (164-177): Assertion violation happens here

test/libsolidity/smtCheckerTests/modifiers/modifier_overflow.sol

@@ -0,0 +1,18 @@
+pragma experimental SMTChecker;
+
+contract C
+{
+	uint x;
+
+	modifier m {
+		require(x > 0);
+		_;
+	}
+
+	function f() m public {
+		assert(x > 0);
+		x = x + 1;
+	}
+}
+// ----
+// Warning: (145-150): Overflow (resulting value larger than 2**256 - 1) happens here

test/libsolidity/smtCheckerTests/modifiers/modifier_parameter_copy.sol

@@ -0,0 +1,15 @@
+pragma experimental SMTChecker;
+
+contract C
+{
+	modifier m(uint x) {
+		x == 2;
+		_;
+	}
+
+	function f(uint x) m(x) public pure {
+		assert(x == 2);
+	}
+}
+// ----
+// Warning: (128-142): Assertion violation happens here

test/libsolidity/smtCheckerTests/modifiers/modifier_parameters.sol

@@ -0,0 +1,18 @@
+pragma experimental SMTChecker;
+
+contract C
+{
+	uint s;
+	modifier m(uint a) {
+		// Condition is always true for m(2).
+		require(a > 0);
+		_;
+	}
+
+	function f(uint x) m(x) m(2) m(s) public view {
+		assert(x > 0);
+		assert(s > 0);
+	}
+}
+// ----
+// Warning: (127-132): Condition is always true.

test/libsolidity/smtCheckerTests/modifiers/modifier_return.sol

@@ -0,0 +1,21 @@
+pragma experimental SMTChecker;
+
+contract C
+{
+	modifier m(uint x) {
+		require(x == 2);
+		_;
+		return;
+	}
+
+	modifier n(uint x) {
+		require(x == 3);
+		_;
+	}
+
+	function f(uint x) m(x) n(x) public pure {
+		assert(x == 3);
+	}
+}
+// ----
+// Warning: (138-144): Condition is always false.

test/libsolidity/smtCheckerTests/modifiers/modifier_same_local_variables.sol

@@ -0,0 +1,15 @@
+pragma experimental SMTChecker;
+
+contract C
+{
+	modifier m {
+		uint x = 2;
+		_;
+	}
+
+	function f(uint x) m public pure {
+		assert(x == 2);
+	}
+}
+// ----
+// Warning: (121-135): Assertion violation happens here

test/libsolidity/smtCheckerTests/modifiers/modifier_simple.sol

@@ -0,0 +1,15 @@
+pragma experimental SMTChecker;
+
+contract C
+{
+	uint x;
+
+	modifier m {
+		require(x > 0);
+		_;
+	}
+
+	function f() m public view {
+		assert(x > 0);
+	}
+}

test/libsolidity/smtCheckerTests/modifiers/modifier_two_invocations.sol

@@ -0,0 +1,21 @@
+pragma experimental SMTChecker;
+
+contract C
+{
+	uint x;
+
+	modifier m {
+		// Condition is always true for the second invocation.
+		require(x > 0);
+		require(x < 10000);
+		_;
+		assert(x > 1);
+	}
+
+	function f() m m public {
+		x = x + 1;
+	}
+}
+// ----
+// Warning: (137-142): Condition is always true.
+// Warning: (155-164): Condition is always true.

test/libsolidity/smtCheckerTests/modifiers/modifier_two_placeholders.sol

@@ -0,0 +1,22 @@
+pragma experimental SMTChecker;
+
+contract C
+{
+	uint x;
+
+	modifier m {
+		require(x > 0);
+		require(x < 10000);
+		_;
+		assert(x > 1);
+		_;
+		assert(x > 2);
+		assert(x > 10);
+	}
+
+	function f() m public {
+		x = x + 1;
+	}
+}
+// ----
+// Warning: (156-170): Assertion violation happens here