[SMTChecker] Refactor CHC loops and add if blocks

test/libsolidity/smtCheckerTests/loops/do_while_break.sol

@@ -0,0 +1,15 @@
+pragma experimental SMTChecker;
+
+contract C {
+	function f() public pure {
+		uint x;
+		do {
+			break;
+			x = 1;
+		} while (x == 0);
+		assert(x == 0);
+	}
+}
+// ----
+// Warning: (104-109): Unreachable code.
+// Warning: (122-128): Unreachable code.

test/libsolidity/smtCheckerTests/loops/do_while_break_2.sol

@@ -0,0 +1,19 @@
+pragma experimental SMTChecker;
+
+contract C {
+	function f() public pure {
+		uint a = 0;
+		while (true) {
+			do {
+				break;
+				a = 2;
+			} while (true);
+			a = 1;
+			break;
+		}
+		assert(a == 1);
+	}
+}
+// ----
+// Warning: (128-133): Unreachable code.
+// Warning: (147-151): Unreachable code.

test/libsolidity/smtCheckerTests/loops/do_while_break_2_fail.sol

@@ -0,0 +1,20 @@
+pragma experimental SMTChecker;
+
+contract C {
+	function f() public pure {
+		uint a = 0;
+		while (true) {
+			do {
+				break;
+				a = 2;
+			} while (true);
+			a = 1;
+			break;
+		}
+		assert(a == 2);
+	}
+}
+// ----
+// Warning: (128-133): Unreachable code.
+// Warning: (147-151): Unreachable code.
+// Warning: (180-194): Assertion violation happens here

test/libsolidity/smtCheckerTests/loops/do_while_break_fail.sol

@@ -0,0 +1,16 @@
+pragma experimental SMTChecker;
+
+contract C {
+	function f() public pure {
+		uint x;
+		do {
+			break;
+			x = 1;
+		} while (x == 0);
+		assert(x == 1);
+	}
+}
+// ----
+// Warning: (104-109): Unreachable code.
+// Warning: (122-128): Unreachable code.
+// Warning: (133-147): Assertion violation happens here

test/libsolidity/smtCheckerTests/loops/do_while_continue.sol

@@ -0,0 +1,14 @@
+pragma experimental SMTChecker;
+
+contract C {
+	function f() public pure {
+		uint x;
+		do {
+			continue;
+			x = 1;
+		} while (x == 0);
+		assert(x == 0);
+	}
+}
+// ----
+// Warning: (107-112): Unreachable code.

test/libsolidity/smtCheckerTests/loops/for_1_break.sol

@@ -0,0 +1,17 @@
+pragma experimental SMTChecker;
+
+contract C
+{
+	function f(uint x, bool b) public pure {
+		require(x < 10);
+		for (; x < 10; ) {
+			if (b)
+				++x;
+			else {
+				x = 20;
+				break;
+			}
+		}
+		assert(x >= 10);
+	}
+}

test/libsolidity/smtCheckerTests/loops/for_1_break_fail.sol

@@ -0,0 +1,18 @@
+pragma experimental SMTChecker;
+
+contract C
+{
+	function f(uint x, bool b) public pure {
+		for (; x < 10; ) {
+			if (b)
+				++x;
+			else {
+				break;
+			}
+		}
+		// Fails because the loop might break.
+		assert(x >= 10);
+	}
+}
+// ----
+// Warning: (201-216): Assertion violation happens here

test/libsolidity/smtCheckerTests/loops/for_1_continue.sol

@@ -0,0 +1,15 @@
+pragma experimental SMTChecker;
+
+contract C
+{
+	function f(uint x, bool b) public pure {
+		require(x < 10);
+		for (; x < 10; ++x) {
+			if (b) {
+				x = 20;
+				continue;
+			}
+		}
+		assert(x > 0);
+	}
+}

test/libsolidity/smtCheckerTests/loops/for_1_continue_fail.sol

@@ -0,0 +1,18 @@
+pragma experimental SMTChecker;
+
+contract C
+{
+	function f(uint x, bool b) public pure {
+		require(x < 10);
+		for (; x < 10; ) {
+			if (b) {
+				x = 20;
+				continue;
+			}
+			++x;
+		}
+		assert(x > 15);
+	}
+}
+// ----
+// Warning: (185-199): Assertion violation happens here

test/libsolidity/smtCheckerTests/loops/for_break_direct.sol

@@ -0,0 +1,12 @@
+pragma experimental SMTChecker;
+
+contract C
+{
+	function f(uint x) public pure {
+		for (x = 0; x < 10; ++x)
+			break;
+		assert(x == 0);
+	}
+}
+// ----
+// Warning: (102-105): Unreachable code.

test/libsolidity/smtCheckerTests/loops/while_1_break.sol

@@ -12,10 +12,6 @@ contract C
 				break;
 			}
 		}
-		// Assertion is safe but break is unsupported for now
-		// so knowledge is erased.
 		assert(x >= 10);
 	}
 }
-// ----
-// Warning: (274-289): Assertion violation happens here

test/libsolidity/smtCheckerTests/loops/while_1_continue.sol

@@ -3,20 +3,14 @@ pragma experimental SMTChecker;
 contract C
 {
 	function f(uint x, bool b) public pure {
-		require(x < 100);
+		require(x < 10);
 		while (x < 10) {
 			if (b) {
-				x = 15;
+				x = 20;
 				continue;
 			}
-			else
-				x = 20;
-
+			++x;
 		}
-		// Should be safe, but fails due to continue being unsupported
-		// and erasing all knowledge.
-		assert(x >= 15);
+		assert(x >= 10);
 	}
 }
-// ----
-// Warning: (294-309): Assertion violation happens here

test/libsolidity/smtCheckerTests/loops/while_1_continue_fail.sol

@@ -8,9 +8,9 @@ contract C
 			if (b) {
 				x = 15;
 				continue;
+				x = 200;
 			}
-			else
-				x = 20;
+			x = 20;
 
 		}
 		// Fails due to the if.
@@ -18,4 +18,5 @@ contract C
 	}
 }
 // ----
-// Warning: (223-238): Assertion violation happens here
+// Warning: (169-176): Unreachable code.
+// Warning: (227-242): Assertion violation happens here

test/libsolidity/smtCheckerTests/loops/while_2_break.sol

@@ -9,11 +9,8 @@ contract C
 			break;
 			++x;
 		}
-		// Assertion is safe but break is unsupported for now
-		// so knowledge is erased.
 		assert(x == 1);
 	}
 }
 // ----
 // Warning: (128-131): Unreachable code.
-// Warning: (224-238): Assertion violation happens here

test/libsolidity/smtCheckerTests/loops/while_break_direct.sol

@@ -0,0 +1,13 @@
+pragma experimental SMTChecker;
+
+contract C
+{
+	function f(uint x) public pure {
+		x = 0;
+		while (x < 10)
+			break;
+		assert(x == 0);
+	}
+}
+// ----
+// Warning: (98-104): Condition is always true.

test/libsolidity/smtCheckerTests/loops/while_nested_break.sol

@@ -0,0 +1,30 @@
+pragma experimental SMTChecker;
+
+contract C
+{
+	function f(uint x, uint y, bool b, bool c) public pure {
+		require(x < 10);
+		while (x < 10) {
+			if (b) {
+				++x;
+				if (x == 10)
+					x = 15;
+			}
+			else {
+				require(y < 10);
+				while (y < 10) {
+					if (c)
+						++y;
+					else {
+						y = 20;
+						break;
+					}
+				}
+				assert(y >= 10);
+				x = 15;
+				break;
+			}
+		}
+		assert(x >= 15);
+	}
+}

test/libsolidity/smtCheckerTests/loops/while_nested_break_fail.sol

@@ -0,0 +1,33 @@
+pragma experimental SMTChecker;
+
+contract C
+{
+	function f(uint x, uint y, bool b, bool c) public pure {
+		require(x < 10);
+		while (x < 10) {
+			if (b) {
+				++x;
+				if (x == 10)
+					x = 15;
+			}
+			else {
+				require(y < 10);
+				while (y < 10) {
+					if (c)
+						++y;
+					else {
+						y = 20;
+						break;
+					}
+				}
+				assert(y >= 15);
+				x = 15;
+				break;
+			}
+		}
+		assert(x >= 20);
+	}
+}
+// ----
+// Warning: (329-344): Assertion violation happens here
+// Warning: (380-395): Assertion violation happens here

test/libsolidity/smtCheckerTests/loops/while_nested_continue.sol

@@ -0,0 +1,28 @@
+pragma experimental SMTChecker;
+
+contract C
+{
+	function f(uint x, uint y, bool b, bool c) public pure {
+		require(x < 10);
+		while (x < 10) {
+			if (b) {
+				x = 20;
+				continue;
+			}
+			else {
+				require(y < 10);
+				while (y < 10) {
+					if (c) {
+						y = 20;
+						continue;
+					}
+					y = 15;
+					break;
+				}
+				assert(y >= 15);
+				x = y;
+			}
+		}
+		assert(x >= 15);
+	}
+}

test/libsolidity/smtCheckerTests/loops/while_nested_continue_fail.sol

@@ -0,0 +1,31 @@
+pragma experimental SMTChecker;
+
+contract C
+{
+	function f(uint x, uint y, bool b, bool c) public pure {
+		require(x < 10);
+		while (x < 10) {
+			if (b) {
+				x = 15;
+				continue;
+			}
+			else {
+				require(y < 10);
+				while (y < 10) {
+					if (c) {
+						y = 20;
+						continue;
+					}
+					y = 15;
+					break;
+				}
+				assert(y >= 20);
+				x = y;
+			}
+		}
+		assert(x >= 20);
+	}
+}
+// ----
+// Warning: (323-338): Assertion violation happens here
+// Warning: (362-377): Assertion violation happens here