From a3b81e9189610a5b1a3dd212aafcb4d8290047ec Mon Sep 17 00:00:00 2001
From: hushunchao <shunchao.hu@outlook.com>
Date: Mon, 6 Jan 2025 11:48:32 +0800
Subject: [PATCH] core: Add "add" operation for the derived set

This commit adds "add" operation for the derived set using the set of
allocations and complete the help information.

To add some allocation calculated set S' to the derived set, add the following
to any command that calculates S':
  /setOperation add

The derived set is then referred to as "derived".
Closes #17
---
 src/Allocations/Set.h                    |  7 ++++++
 src/Allocations/Subcommands/Subcommand.h | 28 +++++++++++++++++-------
 2 files changed, 27 insertions(+), 8 deletions(-)

diff --git a/src/Allocations/Set.h b/src/Allocations/Set.h
index 2dd0d78..10d97dc 100644
--- a/src/Allocations/Set.h
+++ b/src/Allocations/Set.h
@@ -60,6 +60,13 @@ class Set {
       *to++ = *from++;
     }
   }
+  void Add(const Set<Offset> &other) {
+    uint64_t *to = _asU64.get();
+    const uint64_t *from = other._asU64.get();
+    for (AllocationIndex i = 0; i < _numU64; i++) {
+      *to++ |= *from++;
+    }
+  }
   void Subtract(const Set<Offset> &other) {
     uint64_t *to = _asU64.get();
     const uint64_t *from = other._asU64.get();
diff --git a/src/Allocations/Subcommands/Subcommand.h b/src/Allocations/Subcommands/Subcommand.h
index fa736ae..a7ea4f6 100644
--- a/src/Allocations/Subcommands/Subcommand.h
+++ b/src/Allocations/Subcommands/Subcommand.h
@@ -26,6 +26,7 @@ class Subcommand : public Commands::Subcommand {
  public:
   typedef typename Directory<Offset>::AllocationIndex AllocationIndex;
   typedef typename Directory<Offset>::Allocation Allocation;
+  enum SetOperationType { ASSIGN, ADD, SUBTRACT };
   Subcommand(const ProcessImage<Offset>& processImage,
              typename Visitor::Factory& visitorFactory,
              typename Iterator::Factory& iteratorFactory,
@@ -181,8 +182,7 @@ class Subcommand : public Commands::Subcommand {
       }
     }
 
-    bool assignDefault = false;
-    bool subtractFromDefault = false;
+    SetOperationType setOperationType;
 
     size_t numSetOperationArguments = context.GetNumArguments("setOperation");
     if (numSetOperationArguments > 0) {
@@ -192,9 +192,11 @@ class Subcommand : public Commands::Subcommand {
       }
       const std::string& operation = context.Argument("setOperation", 0);
       if (operation == "assign") {
-        assignDefault = true;
+        setOperationType = SetOperationType::ASSIGN;
+      } else if (operation == "add") {
+        setOperationType = SetOperationType::ADD;
       } else if (operation == "subtract") {
-        subtractFromDefault = true;
+        setOperationType = SetOperationType::SUBTRACT;
       } else {
         std::cerr << "Set operation " << operation << " is not supported.\n";
         switchError = true;
@@ -345,10 +347,16 @@ class Subcommand : public Commands::Subcommand {
 
       extendedVisitor.Visit(index, *allocation, visitorRef);
     }
-    if (assignDefault) {
-      _setCache.GetDerived().Assign(visited);
-    } else if (subtractFromDefault) {
-      _setCache.GetDerived().Subtract(visited);
+    switch (setOperationType) {
+      case SetOperationType::ASSIGN:
+        _setCache.GetDerived().Assign(visited);
+        break;
+      case SetOperationType::ADD:
+        _setCache.GetDerived().Add(visited);
+        break;
+      case SetOperationType::SUBTRACT:
+        _setCache.GetDerived().Subtract(visited);
+        break;
     }
   }
 
@@ -386,6 +394,10 @@ class Subcommand : public Commands::Subcommand {
            " be used for automated bug detection.\n\n"
            "/geometricSample <base-in-decimal> causes only entries 1, b, "
            "b**2, b**3...\n to be visited.\n\n"
+           "use \"/setOperation <operation>\" to derive a custome set.\n"
+           " assign: initialize the derived set based on some calculated set.\n"
+           " add: add some calculated set to the derived set.\n"
+           " subtrace: subtract some calculated set from the derived set.\n\n"
            "After restrictions have been applied, the /extend switch can be"
            " used to extend\n"
            " the set to adjacent allocations.  See USERGUIDE.md for details.\n";