Merge pull request #471 from secure-software-engineering/f-LCAImprovements

LCA improvements

Author: pdschubert

include/phasar/PhasarLLVM/DataFlowSolver/IfdsIde/Problems/IDELinearConstantAnalysis.h

@@ -19,6 +19,7 @@
 #include "phasar/PhasarLLVM/DataFlowSolver/IfdsIde/EdgeFunctionComposer.h"
 #include "phasar/PhasarLLVM/DataFlowSolver/IfdsIde/IDETabulationProblem.h"
 #include "phasar/PhasarLLVM/Domain/AnalysisDomain.h"
+#include "phasar/PhasarLLVM/Utils/LatticeDomain.h"
 
 namespace llvm {
 class Instruction;
@@ -31,7 +32,7 @@ namespace psr {
 
 struct IDELinearConstantAnalysisDomain : public LLVMAnalysisDomainDefault {
   // int64_t corresponds to llvm's type of constant integer
-  using l_t = int64_t;
+  using l_t = LatticeDomain<int64_t>;
 };
 
 class LLVMBasedICFG;
@@ -176,10 +177,10 @@ class IDELinearConstantAnalysis
                       public std::enable_shared_from_this<GenConstant> {
   private:
     const unsigned GenConstantId;
-    const l_t IntConst;
+    const int64_t IntConst;
 
   public:
-    explicit GenConstant(l_t IntConst);
+    explicit GenConstant(int64_t IntConst);
 
     l_t computeTarget(l_t Source) override;
 
@@ -253,7 +254,7 @@ class IDELinearConstantAnalysis
    * @param rop right operand
    * @return Result of binary operation
    */
-  static l_t executeBinOperation(unsigned Op, l_t Lop, l_t Rop);
+  static l_t executeBinOperation(unsigned Op, l_t LVal, l_t RVal);
 
   static char opToChar(unsigned Op);
 

include/phasar/PhasarLLVM/Utils/LatticeDomain.h

@@ -10,20 +10,27 @@
 #ifndef PHASAR_PHASARLLVM_UTILS_LATTICEDOMAIN_H
 #define PHASAR_PHASARLLVM_UTILS_LATTICEDOMAIN_H
 
-#include "llvm/Support/ErrorHandling.h"
-
 #include <iostream>
+#include <type_traits>
 #include <variant>
 
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/raw_ostream.h"
+
+#include "phasar/Utils/TypeTraits.h"
+
 namespace psr {
 
 /// Represents the infimum of the lattice:
 /// Top is the greatest element that is less than or equal to all elements of
 /// the lattice.
 struct Top {};
 
-static inline std::ostream &operator<<(std::ostream &OS,
-                                       [[maybe_unused]] const Top &T) {
+inline std::ostream &operator<<(std::ostream &OS, Top /*unused*/) {
+  return OS << "Top";
+}
+
+inline llvm::raw_ostream &operator<<(llvm::raw_ostream &OS, Top /*unused*/) {
   return OS << "Top";
 }
 
@@ -32,43 +39,96 @@ static inline std::ostream &operator<<(std::ostream &OS,
 /// of the lattice.
 struct Bottom {};
 
-static inline std::ostream &operator<<(std::ostream &OS,
-                                       [[maybe_unused]] const Bottom &B) {
+inline std::ostream &operator<<(std::ostream &OS, Bottom /*unused*/) {
   return OS << "Bottom";
 }
 
-/// A easy shorthand to construct a complete lattice of L.
-template <typename L> using LatticeDomain = std::variant<L, Top, Bottom>;
+inline llvm::raw_ostream &operator<<(llvm::raw_ostream &OS, Bottom /*unused*/) {
+  return OS << "Bottom";
+}
 
+/// A easy shorthand to construct a complete lattice of L.
 template <typename L>
+struct LatticeDomain : public std::variant<Top, L, Bottom> {
+  using std::variant<Top, L, Bottom>::variant;
+
+  [[nodiscard]] inline bool isBottom() const noexcept {
+    return std::holds_alternative<Bottom>(*this);
+  }
+  [[nodiscard]] inline bool isTop() const noexcept {
+    return std::holds_alternative<Top>(*this);
+  }
+  [[nodiscard]] inline L *getValueOrNull() noexcept {
+    return std::get_if<L>(this);
+  }
+  [[nodiscard]] inline const L *getValueOrNull() const noexcept {
+    return std::get_if<L>(this);
+  }
+};
+
+template <typename L,
+          typename = std::void_t<decltype(std::declval<std::ostream &>()
+                                          << std::declval<L>())>>
 inline std::ostream &operator<<(std::ostream &OS, const LatticeDomain<L> &LD) {
-  if (auto T = std::get_if<Top>(&LD)) {
-    return OS << *T;
+  if (LD.isBottom()) {
+    return OS << "Bottom";
   }
-  if (auto B = std::get_if<Bottom>(&LD)) {
-    return OS << *B;
+  if (LD.isTop()) {
+    return OS << "Top";
   }
-  return OS << std::get<L>(LD);
+
+  const auto *Val = LD.getValueOrNull();
+  assert(Val && "Only alternative remaining is L");
+  return OS << *Val;
+}
+
+template <typename L,
+          typename = std::void_t<decltype(std::declval<llvm::raw_ostream &>()
+                                          << std::declval<L>())>>
+inline llvm::raw_ostream &operator<<(llvm::raw_ostream &OS,
+                                     const LatticeDomain<L> &LD) {
+  if (LD.isBottom()) {
+    return OS << "Bottom";
+  }
+  if (LD.isTop()) {
+    return OS << "Top";
+  }
+
+  const auto *Val = LD.getValueOrNull();
+  assert(Val && "Only alternative remaining is L");
+  return OS << *Val;
 }
 
 template <typename L>
 inline bool operator==(const LatticeDomain<L> &Lhs,
                        const LatticeDomain<L> &Rhs) {
-  if (std::holds_alternative<Top>(Lhs) && std::holds_alternative<Top>(Rhs)) {
-    return true;
+  if (Lhs.index() != Rhs.index()) {
+    return false;
   }
-  if (std::holds_alternative<Bottom>(Lhs) &&
-      std::holds_alternative<Bottom>(Rhs)) {
-    return true;
+  if (auto LhsPtr = Lhs.getValueOrNull()) {
+    /// No need to check whether Lhs is an L; the indices are already the same
+    return *LhsPtr == *Rhs.getValueOrNull();
   }
-  if (auto *LhsPtr = std::get_if<L>(&Lhs)) {
-    if (auto *RhsPtr = std::get_if<L>(&Rhs)) {
-      return *LhsPtr == *RhsPtr;
-    }
+  return true;
+}
+
+template <
+    typename L, typename LL,
+    typename = std::void_t<decltype(std::declval<LL>() == std::declval<L>())>>
+inline bool operator==(const LL &Lhs, const LatticeDomain<L> Rhs) {
+  if (auto RVal = Rhs.getValueOrNull()) {
+    return Lhs == *RVal;
   }
   return false;
 }
 
+template <
+    typename L, typename LL,
+    typename = std::void_t<decltype(std::declval<LL>() == std::declval<L>())>>
+inline bool operator==(const LatticeDomain<L> Lhs, const LL &Rhs) {
+  return Rhs == Lhs;
+}
+
 template <typename L>
 inline bool operator!=(const LatticeDomain<L> &Lhs,
                        const LatticeDomain<L> &Rhs) {
@@ -78,26 +138,24 @@ inline bool operator!=(const LatticeDomain<L> &Lhs,
 template <typename L>
 inline bool operator<(const LatticeDomain<L> &Lhs,
                       const LatticeDomain<L> &Rhs) {
-  // Top < (Lhs::L < Rhs::L) < Bottom
-  if (std::holds_alternative<Top>(Rhs)) {
+  /// Top < (Lhs::L < Rhs::L) < Bottom
+  if (Rhs.isTop()) {
     return false;
   }
-  if (std::holds_alternative<Top>(Lhs)) {
+  if (Lhs.isTop()) {
     return true;
   }
-
-  if (auto *LhsPtr = std::get_if<L>(&Lhs)) {
-    if (auto *RhsPtr = std::get_if<L>(&Rhs)) {
+  if (auto LhsPtr = Lhs.getValueOrNull()) {
+    if (auto RhsPtr = Rhs.getValueOrNull()) {
       return *LhsPtr < *RhsPtr;
     }
   }
-
-  if (std::holds_alternative<Bottom>(Rhs)) {
-    return !std::holds_alternative<Bottom>(Lhs);
-  }
-  if (std::holds_alternative<Bottom>(Lhs)) {
+  if (Lhs.isBottom()) {
     return false;
   }
+  if (Rhs.isBottom()) {
+    return true;
+  }
   llvm_unreachable("All comparision cases should be handled above.");
 }
 

include/phasar/Utils/TypeTraits.h

@@ -13,6 +13,7 @@
 #include <ostream>
 #include <tuple>
 #include <type_traits>
+#include <variant>
 
 #include "llvm/Support/raw_ostream.h"
 
@@ -109,6 +110,15 @@ constexpr bool is_std_hashable_v = detail::is_std_hashable<T>::value; // NOLINT
 template <typename T>
 constexpr bool is_llvm_hashable_v = // NOLINT
     detail::is_llvm_hashable<T>::value;
+
+template <typename T> struct is_variant : std::false_type {}; // NOLINT
+
+template <typename... Args>
+struct is_variant<std::variant<Args...>> : std::true_type {}; // NOLINT
+
+template <typename T>
+inline constexpr bool is_variant_v = is_variant<T>::value; // NOLINT
+
 // NOLINTEND(readability-identifier-naming)
 } // namespace psr