Support for <<, >> and |, &, ^ in ValueEvaluator and `Bin…

…aryOperation` (#1333)

Support for `<<`, `>>` and `|` in `ValueEvaluator` and `BinaryOperation`

cpg-analysis/src/main/kotlin/de/fraunhofer/aisec/cpg/analysis/ValueEvaluator.kt

@@ -163,6 +163,11 @@ open class ValueEvaluator(
             "/=" -> handleDiv(lhsValue, rhsValue, expr)
             "*",
             "*=" -> handleTimes(lhsValue, rhsValue, expr)
+            "<<" -> handleShiftLeft(lhsValue, rhsValue, expr)
+            ">>" -> handleShiftRight(lhsValue, rhsValue, expr)
+            "&" -> handleBitwiseAnd(lhsValue, rhsValue, expr)
+            "|" -> handleBitwiseOr(lhsValue, rhsValue, expr)
+            "^" -> handleBitwiseXor(lhsValue, rhsValue, expr)
             ">" -> handleGreater(lhsValue, rhsValue, expr)
             ">=" -> handleGEq(lhsValue, rhsValue, expr)
             "<" -> handleLess(lhsValue, rhsValue, expr)
@@ -202,6 +207,51 @@ open class ValueEvaluator(
         }
     }
 
+    private fun handleShiftLeft(lhsValue: Any?, rhsValue: Any?, expr: Expression?): Any? {
+        return when {
+            // right side must always be an int
+            lhsValue is Int && rhsValue is Int -> lhsValue shl rhsValue
+            lhsValue is Long && rhsValue is Int -> lhsValue shl rhsValue
+            else -> cannotEvaluate(expr, this)
+        }
+    }
+
+    private fun handleShiftRight(lhsValue: Any?, rhsValue: Any?, expr: Expression?): Any? {
+        return when {
+            // right side must always be an int
+            lhsValue is Int && rhsValue is Int -> lhsValue shr rhsValue
+            lhsValue is Long && rhsValue is Int -> lhsValue shr rhsValue
+            else -> cannotEvaluate(expr, this)
+        }
+    }
+
+    private fun handleBitwiseAnd(lhsValue: Any?, rhsValue: Any?, expr: Expression?): Any? {
+        return when {
+            // left and right must be equal and only long and int are supported
+            lhsValue is Int && rhsValue is Int -> lhsValue and rhsValue
+            lhsValue is Long && rhsValue is Long -> lhsValue and rhsValue
+            else -> cannotEvaluate(expr, this)
+        }
+    }
+
+    private fun handleBitwiseOr(lhsValue: Any?, rhsValue: Any?, expr: Expression?): Any? {
+        return when {
+            // left and right must be equal and only long and int are supported
+            lhsValue is Int && rhsValue is Int -> lhsValue or rhsValue
+            lhsValue is Long && rhsValue is Long -> lhsValue or rhsValue
+            else -> cannotEvaluate(expr, this)
+        }
+    }
+
+    private fun handleBitwiseXor(lhsValue: Any?, rhsValue: Any?, expr: Expression?): Any? {
+        return when {
+            // left and right must be equal and only long and int are supported
+            lhsValue is Int && rhsValue is Int -> lhsValue xor rhsValue
+            lhsValue is Long && rhsValue is Long -> lhsValue xor rhsValue
+            else -> cannotEvaluate(expr, this)
+        }
+    }
+
     private fun handleGreater(lhsValue: Any?, rhsValue: Any?, expr: Expression?): Any? {
         return if (lhsValue is Number && rhsValue is Number) {
             lhsValue.compareTo(rhsValue) > 0

cpg-analysis/src/test/kotlin/de/fraunhofer/aisec/cpg/analysis/ValueEvaluatorTest.kt

@@ -639,6 +639,106 @@ class ValueEvaluatorTest {
         }
     }
 
+    @Test
+    fun testHandleShiftLeft() {
+        with(TestHandler(TestLanguageFrontend())) {
+            val binOp = newBinaryOperator("<<")
+            // Int.plus
+            binOp.lhs = newLiteral(3, primitiveType("int"))
+            binOp.rhs = newLiteral(2, primitiveType("int"))
+            assertEquals(12, ValueEvaluator().evaluate(binOp))
+
+            // Long.plus
+            binOp.lhs = newLiteral(3L, primitiveType("long"))
+            binOp.rhs = newLiteral(2, primitiveType("int"))
+            assertEquals(12L, ValueEvaluator().evaluate(binOp))
+
+            binOp.lhs = newLiteral("Hello", primitiveType("string"))
+            binOp.rhs = newLiteral(" world", primitiveType("string"))
+            assertEquals("{<<}", ValueEvaluator().evaluate(binOp))
+        }
+    }
+
+    @Test
+    fun testHandleShiftRight() {
+        with(TestHandler(TestLanguageFrontend())) {
+            val binOp = newBinaryOperator(">>")
+            // Int.plus
+            binOp.lhs = newLiteral(3, primitiveType("int"))
+            binOp.rhs = newLiteral(2, primitiveType("int"))
+            assertEquals(0, ValueEvaluator().evaluate(binOp))
+
+            // Long.plus
+            binOp.lhs = newLiteral(3L, primitiveType("long"))
+            binOp.rhs = newLiteral(2, primitiveType("int"))
+            assertEquals(0L, ValueEvaluator().evaluate(binOp))
+
+            binOp.lhs = newLiteral("Hello", primitiveType("string"))
+            binOp.rhs = newLiteral(" world", primitiveType("string"))
+            assertEquals("{>>}", ValueEvaluator().evaluate(binOp))
+        }
+    }
+
+    @Test
+    fun testHandleBitwiseAnd() {
+        with(TestHandler(TestLanguageFrontend())) {
+            val binOp = newBinaryOperator("&")
+            // Int.plus
+            binOp.lhs = newLiteral(3, primitiveType("int"))
+            binOp.rhs = newLiteral(2, primitiveType("int"))
+            assertEquals(2, ValueEvaluator().evaluate(binOp))
+
+            // Long.plus
+            binOp.lhs = newLiteral(3L, primitiveType("long"))
+            binOp.rhs = newLiteral(2L, primitiveType("long"))
+            assertEquals(2L, ValueEvaluator().evaluate(binOp))
+
+            binOp.lhs = newLiteral("Hello", primitiveType("string"))
+            binOp.rhs = newLiteral(" world", primitiveType("string"))
+            assertEquals("{&}", ValueEvaluator().evaluate(binOp))
+        }
+    }
+
+    @Test
+    fun testHandleBitwiseOr() {
+        with(TestHandler(TestLanguageFrontend())) {
+            val binOp = newBinaryOperator("|")
+            // Int.plus
+            binOp.lhs = newLiteral(3, primitiveType("int"))
+            binOp.rhs = newLiteral(2, primitiveType("int"))
+            assertEquals(3, ValueEvaluator().evaluate(binOp))
+
+            // Long.plus
+            binOp.lhs = newLiteral(3L, primitiveType("long"))
+            binOp.rhs = newLiteral(2L, primitiveType("long"))
+            assertEquals(3L, ValueEvaluator().evaluate(binOp))
+
+            binOp.lhs = newLiteral("Hello", primitiveType("string"))
+            binOp.rhs = newLiteral(" world", primitiveType("string"))
+            assertEquals("{|}", ValueEvaluator().evaluate(binOp))
+        }
+    }
+
+    @Test
+    fun testHandleBitwiseXor() {
+        with(TestHandler(TestLanguageFrontend())) {
+            val binOp = newBinaryOperator("^")
+            // Int.plus
+            binOp.lhs = newLiteral(3, primitiveType("int"))
+            binOp.rhs = newLiteral(2, primitiveType("int"))
+            assertEquals(1, ValueEvaluator().evaluate(binOp))
+
+            // Long.plus
+            binOp.lhs = newLiteral(3L, primitiveType("long"))
+            binOp.rhs = newLiteral(2L, primitiveType("long"))
+            assertEquals(1L, ValueEvaluator().evaluate(binOp))
+
+            binOp.lhs = newLiteral("Hello", primitiveType("string"))
+            binOp.rhs = newLiteral(" world", primitiveType("string"))
+            assertEquals("{^}", ValueEvaluator().evaluate(binOp))
+        }
+    }
+
     @Test
     fun testHandleUnary() {
         with(TestHandler(TestLanguageFrontend())) {

cpg-core/src/main/kotlin/de/fraunhofer/aisec/cpg/ScopeManager.kt

@@ -614,16 +614,16 @@ class ScopeManager : ScopeProvider {
      * Resolves only references to Values in the current scope, static references to other visible
      * records are not resolved over the ScopeManager.
      *
-     * @param scope
      * @param ref
      * @return
      *
      * TODO: We should merge this function with [.resolveFunction]
      */
-    @JvmOverloads
-    fun resolveReference(ref: Reference, startScope: Scope? = currentScope): ValueDeclaration? {
+    fun resolveReference(ref: Reference): ValueDeclaration? {
+        val startScope = ref.scope
+
         // Retrieve a unique tag for the particular reference based on the current scope
-        val tag = ref.buildUniqueTag(startScope)
+        val tag = ref.uniqueTag
 
         // If we find a match in our symbol table, we can immediately return the declaration
         var decl = symbolTable[tag]

cpg-core/src/main/kotlin/de/fraunhofer/aisec/cpg/frontends/Language.kt

@@ -164,6 +164,9 @@ abstract class Language<T : LanguageFrontend<*, *>> : Node() {
             "-",
             "*",
             "/" -> arithmeticOpTypePropagation(operation.lhs.type, operation.rhs.type)
+            "&",
+            "|",
+            "^",
             "<<",
             ">>" ->
                 if (operation.lhs.type.isPrimitive && operation.rhs.type.isPrimitive) {

cpg-core/src/main/kotlin/de/fraunhofer/aisec/cpg/graph/statements/expressions/Reference.kt

@@ -32,7 +32,6 @@ import de.fraunhofer.aisec.cpg.graph.declarations.Declaration
 import de.fraunhofer.aisec.cpg.graph.declarations.ValueDeclaration
 import de.fraunhofer.aisec.cpg.graph.declarations.VariableDeclaration
 import de.fraunhofer.aisec.cpg.graph.edge.Properties
-import de.fraunhofer.aisec.cpg.graph.scopes.Scope
 import de.fraunhofer.aisec.cpg.graph.types.HasType
 import de.fraunhofer.aisec.cpg.graph.types.Type
 import de.fraunhofer.aisec.cpg.passes.SymbolResolver
@@ -160,9 +159,10 @@ open class Reference : Expression(), HasType.TypeObserver {
      * Its purpose is to cache symbol resolutions, similar to LLVMs system of Unified Symbol
      * Resolution (USR).
      */
-    fun buildUniqueTag(startScope: Scope?): ReferenceTag {
-        return Objects.hash(this.name, this.resolutionHelper, startScope)
-    }
+    val uniqueTag: ReferenceTag
+        get() {
+            return Objects.hash(this.name, this.resolutionHelper, this.scope)
+        }
 }
 
 typealias ReferenceTag = Int

cpg-core/src/main/kotlin/de/fraunhofer/aisec/cpg/passes/SymbolResolver.kt

@@ -205,7 +205,7 @@ open class SymbolResolver(ctx: TranslationContext) : ComponentPass(ctx) {
             // Peek into the declaration, and if it is a variable, we can proceed normally, as we
             // are running into the special case explained above. Otherwise, we abort here (for
             // now).
-            wouldResolveTo = scopeManager.resolveReference(current, current.scope)
+            wouldResolveTo = scopeManager.resolveReference(current)
             if (wouldResolveTo !is VariableDeclaration && wouldResolveTo !is ParameterDeclaration) {
                 return
             }
@@ -214,9 +214,7 @@ open class SymbolResolver(ctx: TranslationContext) : ComponentPass(ctx) {
         // Only consider resolving, if the language frontend did not specify a resolution. If we
         // already have populated the wouldResolveTo variable, we can re-use this instead of
         // resolving again
-        var refersTo =
-            current.refersTo
-                ?: wouldResolveTo ?: scopeManager.resolveReference(current, current.scope)
+        var refersTo = current.refersTo ?: wouldResolveTo ?: scopeManager.resolveReference(current)
 
         var recordDeclType: Type? = null
         if (currentClass != null) {

cpg-core/src/test/kotlin/de/fraunhofer/aisec/cpg/passes/SymbolResolverTest.kt

@@ -31,6 +31,8 @@ import de.fraunhofer.aisec.cpg.TestUtils.assertRefersTo
 import de.fraunhofer.aisec.cpg.graph.*
 import de.fraunhofer.aisec.cpg.graph.statements.expressions.ConstructExpression
 import de.fraunhofer.aisec.cpg.graph.statements.expressions.MemberCallExpression
+import de.fraunhofer.aisec.cpg.graph.statements.expressions.Reference
+import de.fraunhofer.aisec.cpg.graph.statements.expressions.ReferenceTag
 import kotlin.test.Test
 import kotlin.test.assertEquals
 import kotlin.test.assertIs
@@ -71,4 +73,23 @@ class SymbolResolverTest {
         assertNotNull(construct)
         assertInvokes(construct, constructor)
     }
+
+    @Test
+    fun testUniqueTags() {
+        val result = GraphExamples.getConditionalExpression()
+
+        val map = mutableMapOf<ReferenceTag, MutableList<Reference>>()
+
+        val refs = result.refs
+        refs.forEach {
+            // Build a unique tag based on the scope of the reference is in (since this is usually
+            // the start scope)
+            val list = map.computeIfAbsent(it.uniqueTag) { mutableListOf() }
+            list += it
+
+            // All elements in the list must have the same scope and name
+            assertEquals(1, list.map { ref -> ref.scope }.toSet().size)
+            assertEquals(1, list.map { ref -> ref.name }.toSet().size)
+        }
+    }
 }

cpg-language-go/src/test/kotlin/de/fraunhofer/aisec/cpg/frontends/golang/DeclarationTest.kt

@@ -303,10 +303,16 @@ class DeclarationTest {
         with(tu) {
             val values =
                 mapOf(
+                    "zeroShift" to Pair(0, objectType("int")),
+                    "zeroAnd" to Pair(0, objectType("int")),
                     "one" to Pair(1, objectType("p.custom")),
                     "oneAsWell" to Pair(1, objectType("p.custom")),
+                    "oneShift" to Pair(1, primitiveType("int")),
                     "two" to Pair(2, primitiveType("int")),
+                    "twoShift" to Pair(2, primitiveType("int")),
                     "three" to Pair(3, primitiveType("int")),
+                    "threeOr" to Pair(3, primitiveType("int")),
+                    "threeXor" to Pair(3, primitiveType("int")),
                     "four" to Pair(4, primitiveType("int")),
                     "tenAsWell" to Pair(10, primitiveType("int")),
                     "five" to Pair(5, primitiveType("int")),

cpg-language-go/src/test/resources/golang/const.go

@@ -24,3 +24,12 @@ const (
 	fiveAsWell = 5 + iota*100
 	onehundredandfive
 )
+
+const (
+	oneShift = 1 << iota
+	twoShift
+	zeroShift = 1 >> iota
+	zeroAnd   = oneShift & twoShift
+	threeOr   = oneShift | twoShift
+	threeXor  = oneShift ^ twoShift
+)