Merge pull request #5258 from ethereum/coverage2

Add some simplification tests for operations.

test/libyul/yulOptimizerTests/fullSimplify/operations.yul

@@ -0,0 +1,44 @@
+{
+  let x := mload(0)
+  mstore(1, mul(x, 0))
+  mstore(2, div(x, 0))
+  mstore(3, div(0, x))
+  mstore(4, sdiv(x, 0))
+  mstore(5, sdiv(0, x))
+  mstore(6, and(0, x))
+  mstore(7, and(x, 0))
+  mstore(8, mod(0, x))
+  mstore(9, mod(x, 0))
+  mstore(10, lt(x, x))
+  mstore(11, gt(x, x))
+  mstore(12, slt(x, x))
+  mstore(13, sgt(x, x))
+  mstore(14, mod(x, x))
+  mstore(15, and(x, not(x)))
+  mstore(16, and(not(x), x))
+  mstore(17, or(x, not(x)))
+  mstore(18, or(not(x), x))
+}
+// ----
+// fullSimplify
+// {
+//     pop(mload(0))
+//     mstore(1, 0)
+//     mstore(2, 0)
+//     mstore(3, 0)
+//     mstore(4, 0)
+//     mstore(5, 0)
+//     mstore(6, 0)
+//     mstore(7, 0)
+//     mstore(8, 0)
+//     mstore(9, 0)
+//     mstore(10, 0)
+//     mstore(11, 0)
+//     mstore(12, 0)
+//     mstore(13, 0)
+//     mstore(14, 0)
+//     mstore(15, 0)
+//     mstore(16, 0)
+//     mstore(17, 0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff)
+//     mstore(18, 0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff)
+// }

test/libyul/yulOptimizerTests/fullSimplify/signextend.yul

@@ -0,0 +1,12 @@
+{
+  let x := 7
+  mstore(0, signextend(50, x))
+  let y := 255
+  mstore(1, signextend(0, y))
+}
+// ----
+// fullSimplify
+// {
+//     mstore(0, 7)
+//     mstore(1, 0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff)
+// }