Swift: Understand overflow binary bitwise operations.

Author: geoffw0

swift/ql/lib/codeql/swift/elements/expr/BitwiseOperation.qll

@@ -73,20 +73,22 @@ class XorBitwiseExpr extends BinaryExpr {
  * A bitwise shift left expression.
  * ```
  * a << b
+ * a &<<
  * ```
  */
 class ShiftLeftBitwiseExpr extends BinaryExpr {
-  ShiftLeftBitwiseExpr() { this.getStaticTarget().getName() = "<<(_:_:)" }
+  ShiftLeftBitwiseExpr() { this.getStaticTarget().getName() = ["<<(_:_:)", "&<<(_:_:)"] }
 }
 
 /**
  * A bitwise shift right expression.
  * ```
  * a >> b
+ * a &>>
  * ```
  */
 class ShiftRightBitwiseExpr extends BinaryExpr {
-  ShiftRightBitwiseExpr() { this.getStaticTarget().getName() = ">>(_:_:)" }
+  ShiftRightBitwiseExpr() { this.getStaticTarget().getName() = [">>(_:_:)", "&>>(_:_:)"] }
 }
 
 /**

swift/ql/test/library-tests/elements/expr/bitwiseopration/bitwiseoperation.expected

@@ -4,3 +4,5 @@
 | bitwiseoperation.swift:5:7:5:11 | ... .^(_:_:) ... | BinaryBitwiseOperation, XorBitwiseExpr |
 | bitwiseoperation.swift:6:7:6:12 | ... .<<(_:_:) ... | BinaryBitwiseOperation, ShiftLeftBitwiseExpr |
 | bitwiseoperation.swift:7:7:7:12 | ... .>>(_:_:) ... | BinaryBitwiseOperation, ShiftRightBitwiseExpr |
+| bitwiseoperation.swift:10:7:10:13 | ... .&<<(_:_:) ... | BinaryBitwiseOperation, ShiftLeftBitwiseExpr |
+| bitwiseoperation.swift:11:7:11:13 | ... .&>>(_:_:) ... | BinaryBitwiseOperation, ShiftRightBitwiseExpr |

swift/ql/test/library-tests/elements/expr/bitwiseopration/bitwiseoperation.swift

@@ -7,8 +7,8 @@ func bitwise() {
   _ = 1 >> 0
 
   // bitwise operations with overflow
-  _ = 1 &<< 1 // NOT DETECTED
-  _ = 1 &>> 1 // NOT DETECTED
+  _ = 1 &<< 1
+  _ = 1 &>> 1
 
   // pointwise bitwise operations
   let a = SIMD4<Int>(1, 2, 3, 4)