C++/C#: Add new MemoryAccessKind to represent entire allocation

Author: Dave Bartolomeo

cpp/ql/src/semmle/code/cpp/ir/implementation/MemoryAccessKind.qll

@@ -1,6 +1,7 @@
 private newtype TMemoryAccessKind =
   TIndirectMemoryAccess() or
   TBufferMemoryAccess() or
+  TEntireAllocationMemoryAccess() or
   TEscapedMemoryAccess() or
   TNonLocalMemoryAccess() or
   TPhiMemoryAccess() or
@@ -43,6 +44,16 @@ class BufferMemoryAccess extends MemoryAccessKind, TBufferMemoryAccess {
   final override predicate usesAddressOperand() { any() }
 }
 
+/**
+ * The operand or results accesses all memory in the contiguous allocation that contains the address
+ * specified by the `AddressOperand` on the same instruction.
+ */
+class EntireAllocationMemoryAccess extends MemoryAccessKind, TEntireAllocationMemoryAccess {
+  override string toString() { result = "alloc" }
+
+  final override predicate usesAddressOperand() { any() }
+}
+
 /**
  * The operand or result accesses all memory whose address has escaped.
  */

cpp/ql/src/semmle/code/cpp/ir/implementation/Opcode.qll

@@ -232,6 +232,31 @@ abstract class BufferReadOpcode extends BufferAccessOpcode {
   final override MemoryAccessKind getReadMemoryAccess() { result instanceof BufferMemoryAccess }
 }
 
+/**
+ * An opcode that access an entire memory allocation.
+ */
+abstract class EntireAllocationAccessOpcode extends Opcode {
+  final override predicate hasAddressOperand() { any() }
+}
+
+/**
+ * An opcode that write to an entire memory allocation.
+ */
+abstract class EntireAllocationWriteOpcode extends EntireAllocationAccessOpcode {
+  final override MemoryAccessKind getWriteMemoryAccess() {
+    result instanceof EntireAllocationMemoryAccess
+  }
+}
+
+/**
+ * An opcode that reads from an entire memory allocation.
+ */
+abstract class EntireAllocationReadOpcode extends EntireAllocationAccessOpcode {
+  final override MemoryAccessKind getReadMemoryAccess() {
+    result instanceof EntireAllocationMemoryAccess
+  }
+}
+
 /**
  * An opcode that accesses a memory buffer whose size is determined by a `BufferSizeOperand`.
  */
@@ -325,7 +350,7 @@ module Opcode {
     final override string toString() { result = "InitializeParameter" }
   }
 
-  class InitializeIndirection extends IndirectWriteOpcode, TInitializeIndirection {
+  class InitializeIndirection extends EntireAllocationWriteOpcode, TInitializeIndirection {
     final override string toString() { result = "InitializeIndirection" }
   }
 
@@ -349,7 +374,7 @@ module Opcode {
     final override string toString() { result = "ReturnVoid" }
   }
 
-  class ReturnIndirection extends IndirectReadOpcode, TReturnIndirection {
+  class ReturnIndirection extends EntireAllocationReadOpcode, TReturnIndirection {
     final override string toString() { result = "ReturnIndirection" }
 
     final override predicate hasOperandInternal(OperandTag tag) {

csharp/ql/src/semmle/code/csharp/ir/implementation/MemoryAccessKind.qll

@@ -1,6 +1,7 @@
 private newtype TMemoryAccessKind =
   TIndirectMemoryAccess() or
   TBufferMemoryAccess() or
+  TEntireAllocationMemoryAccess() or
   TEscapedMemoryAccess() or
   TNonLocalMemoryAccess() or
   TPhiMemoryAccess() or
@@ -43,6 +44,16 @@ class BufferMemoryAccess extends MemoryAccessKind, TBufferMemoryAccess {
   final override predicate usesAddressOperand() { any() }
 }
 
+/**
+ * The operand or results accesses all memory in the contiguous allocation that contains the address
+ * specified by the `AddressOperand` on the same instruction.
+ */
+class EntireAllocationMemoryAccess extends MemoryAccessKind, TEntireAllocationMemoryAccess {
+  override string toString() { result = "alloc" }
+
+  final override predicate usesAddressOperand() { any() }
+}
+
 /**
  * The operand or result accesses all memory whose address has escaped.
  */

csharp/ql/src/semmle/code/csharp/ir/implementation/Opcode.qll

@@ -232,6 +232,31 @@ abstract class BufferReadOpcode extends BufferAccessOpcode {
   final override MemoryAccessKind getReadMemoryAccess() { result instanceof BufferMemoryAccess }
 }
 
+/**
+ * An opcode that access an entire memory allocation.
+ */
+abstract class EntireAllocationAccessOpcode extends Opcode {
+  final override predicate hasAddressOperand() { any() }
+}
+
+/**
+ * An opcode that write to an entire memory allocation.
+ */
+abstract class EntireAllocationWriteOpcode extends EntireAllocationAccessOpcode {
+  final override MemoryAccessKind getWriteMemoryAccess() {
+    result instanceof EntireAllocationMemoryAccess
+  }
+}
+
+/**
+ * An opcode that reads from an entire memory allocation.
+ */
+abstract class EntireAllocationReadOpcode extends EntireAllocationAccessOpcode {
+  final override MemoryAccessKind getReadMemoryAccess() {
+    result instanceof EntireAllocationMemoryAccess
+  }
+}
+
 /**
  * An opcode that accesses a memory buffer whose size is determined by a `BufferSizeOperand`.
  */
@@ -325,7 +350,7 @@ module Opcode {
     final override string toString() { result = "InitializeParameter" }
   }
 
-  class InitializeIndirection extends IndirectWriteOpcode, TInitializeIndirection {
+  class InitializeIndirection extends EntireAllocationWriteOpcode, TInitializeIndirection {
     final override string toString() { result = "InitializeIndirection" }
   }
 
@@ -349,7 +374,7 @@ module Opcode {
     final override string toString() { result = "ReturnVoid" }
   }
 
-  class ReturnIndirection extends IndirectReadOpcode, TReturnIndirection {
+  class ReturnIndirection extends EntireAllocationReadOpcode, TReturnIndirection {
     final override string toString() { result = "ReturnIndirection" }
 
     final override predicate hasOperandInternal(OperandTag tag) {