yul: Set non movable flag to true in simplification rule for byte of right-shifted expression

test/libyul/yulInterpreterTests/pop_byte_shr_call.yul

@@ -0,0 +1,10 @@
+{
+  pop(byte(0, shr(0x8, call(0, 0, 0, 0, 0, 0, 0))))
+}
+// ====
+// EVMVersion: >=constantinople
+// ----
+// Trace:
+//   CALL(0, 0, 0, 0, 0, 0, 0)
+// Memory dump:
+// Storage dump:

test/libyul/yulInterpreterTests/pop_byte_shr_func.yul

@@ -0,0 +1,11 @@
+{
+  function f() -> x { mstore(0, 0x1337) }
+  pop(byte(0, shr(0x8, f())))
+}
+// ====
+// EVMVersion: >=constantinople
+// ----
+// Trace:
+// Memory dump:
+//      0: 0000000000000000000000000000000000000000000000000000000000001337
+// Storage dump:

test/libyul/yulOptimizerTests/expressionSimplifier/pop_byte_shr_call.yul

@@ -0,0 +1,11 @@
+{
+  pop(byte(0, shr(0x8, call(0, 0, 0, 0, 0, 0, 0))))
+}
+// ====
+// EVMVersion: >=constantinople
+// ----
+// step: expressionSimplifier
+//
+// {
+//     pop(byte(0, shr(0x8, call(0, 0, 0, 0, 0, 0, 0))))
+// }

test/libyul/yulOptimizerTests/expressionSimplifier/pop_byte_shr_func.yul

@@ -0,0 +1,14 @@
+{
+  function f() -> x { mstore(0, 1337) }
+  pop(byte(0, shr(0x8, f())))
+}
+// ====
+// EVMVersion: >=constantinople
+// ----
+// step: expressionSimplifier
+//
+// {
+//     function f() -> x
+//     { mstore(0, 1337) }
+//     pop(byte(0, shr(0x8, f())))
+// }

test/libyul/yulOptimizerTests/expressionSimplifier/pop_byte_shr_func_trivial.yul

@@ -0,0 +1,14 @@
+{
+  function f() -> x {}
+  pop(byte(0, shr(0x8, f())))
+}
+// ====
+// EVMVersion: >=constantinople
+// ----
+// step: expressionSimplifier
+//
+// {
+//     function f() -> x
+//     { }
+//     pop(byte(0, shr(0x8, f())))
+// }