[NFC] Wrap Bool::Element (#8149)

Rather than using `bool` directly. This avoids problems with getting the
`std::vector<bool>` overload by accident.

Author: tlively

src/analysis/lattices/bool.h

@@ -24,7 +24,30 @@ namespace wasm::analysis {
 // A lattice with two elements: the top element is `true` and the bottom element
 // is `false`.
 struct Bool {
-  using Element = bool;
+  // Use a wrapper around bool to avoid triggering bool specializations of e.g.
+  // std::vector.
+  struct Element {
+    bool val = false;
+    Element(bool val) : val(val) {}
+    Element() = default;
+    Element(const Element& other) = default;
+    Element(Element&& other) = default;
+    operator bool() const noexcept { return val; }
+    bool operator==(const Element& other) const noexcept {
+      return val == other.val;
+    }
+    bool operator==(bool other) const noexcept { return val == other; }
+    bool operator!=(const Element& other) const noexcept {
+      return !(*this == other);
+    }
+    bool operator!=(bool other) const noexcept { return !(*this == other); }
+    Element& operator=(const Element& other) = default;
+    Element& operator=(Element&& other) = default;
+    Element& operator=(bool other) {
+      val = other;
+      return *this;
+    }
+  };
   Element getBottom() const noexcept { return false; }
   Element getTop() const noexcept { return true; }
   LatticeComparison compare(Element a, Element b) const noexcept {
@@ -37,13 +60,19 @@ struct Bool {
     }
     return false;
   }
+  bool join(Element& joinee, bool joiner) const noexcept {
+    return join(joinee, Element(joiner));
+  }
   bool meet(Element& meetee, Element meeter) const noexcept {
     if (meetee && !meeter) {
       meetee = meeter;
       return true;
     }
     return false;
   }
+  bool meet(Element& meetee, bool meeter) const noexcept {
+    return meet(meetee, Element(meeter));
+  }
 };
 
 #if __cplusplus >= 202002L

test/gtest/lattices.cpp

@@ -161,7 +161,7 @@ TEST(BoolLattice, Compare) {
 
 TEST(BoolLattice, Join) {
   analysis::Bool lattice;
-  bool elem = false;
+  analysis::Bool::Element elem = false;
 
   EXPECT_FALSE(lattice.join(elem, false));
   ASSERT_FALSE(elem);
@@ -178,7 +178,7 @@ TEST(BoolLattice, Join) {
 
 TEST(BoolLattice, Meet) {
   analysis::Bool lattice;
-  bool elem = true;
+  analysis::Bool::Element elem = true;
 
   EXPECT_FALSE(lattice.meet(elem, true));
   ASSERT_TRUE(elem);
@@ -276,7 +276,7 @@ TEST(InvertedLattice, Compare) {
 
 TEST(InvertedLattice, Join) {
   analysis::Inverted inverted(analysis::Bool{});
-  bool elem = true;
+  analysis::Bool::Element elem = true;
 
   EXPECT_FALSE(inverted.join(elem, true));
   ASSERT_TRUE(elem);
@@ -293,7 +293,7 @@ TEST(InvertedLattice, Join) {
 
 TEST(InvertedLattice, Meet) {
   analysis::Inverted inverted(analysis::Bool{});
-  bool elem = false;
+  analysis::Bool::Element elem = false;
 
   EXPECT_FALSE(inverted.meet(elem, false));
   ASSERT_FALSE(elem);
@@ -445,12 +445,14 @@ TEST(LiftLattice, Join) {
 
 TEST(ArrayLattice, GetBottom) {
   analysis::Array<analysis::Bool, 2> array{analysis::Bool{}};
-  EXPECT_EQ(array.getBottom(), (std::array<bool, 2>{false, false}));
+  EXPECT_EQ(array.getBottom(),
+            (std::array<analysis::Bool::Element, 2>{false, false}));
 }
 
 TEST(ArrayLattice, GetTop) {
   analysis::Array<analysis::Bool, 2> array{analysis::Bool{}};
-  EXPECT_EQ(array.getTop(), (std::array<bool, 2>{true, true}));
+  EXPECT_EQ(array.getTop(),
+            (std::array<analysis::Bool::Element, 2>{true, true}));
 }
 
 TEST(ArrayLattice, Compare) {
@@ -473,12 +475,14 @@ TEST(ArrayLattice, Meet) {
 
 TEST(VectorLattice, GetBottom) {
   analysis::Vector<analysis::Bool> vector{analysis::Bool{}, 2};
-  EXPECT_EQ(vector.getBottom(), (std::vector<bool>{false, false}));
+  EXPECT_EQ(vector.getBottom(),
+            (std::vector<analysis::Bool::Element>{false, false}));
 }
 
 TEST(VectorLattice, GetTop) {
   analysis::Vector<analysis::Bool> vector{analysis::Bool{}, 2};
-  EXPECT_EQ(vector.getTop(), (std::vector<bool>{true, true}));
+  EXPECT_EQ(vector.getTop(),
+            (std::vector<analysis::Bool::Element>{true, true}));
 }
 
 TEST(VectorLattice, Compare) {
@@ -505,10 +509,10 @@ TEST(VectorLattice, JoinSingleton) {
   auto elem = vector.getBottom();
 
   EXPECT_FALSE(vector.join(elem, Vec::SingletonElement(0, false)));
-  EXPECT_EQ(elem, (std::vector{false, false}));
+  EXPECT_EQ(elem, (std::vector<analysis::Bool::Element>{false, false}));
 
   EXPECT_TRUE(vector.join(elem, Vec::SingletonElement(1, true)));
-  EXPECT_EQ(elem, (std::vector{false, true}));
+  EXPECT_EQ(elem, (std::vector<analysis::Bool::Element>{false, true}));
 }
 
 TEST(VectorLattice, MeetSingleton) {
@@ -517,10 +521,10 @@ TEST(VectorLattice, MeetSingleton) {
   auto elem = vector.getTop();
 
   EXPECT_FALSE(vector.meet(elem, Vec::SingletonElement(1, true)));
-  EXPECT_EQ(elem, (std::vector{true, true}));
+  EXPECT_EQ(elem, (std::vector<analysis::Bool::Element>{true, true}));
 
   EXPECT_TRUE(vector.meet(elem, Vec::SingletonElement(0, false)));
-  EXPECT_EQ(elem, (std::vector{false, true}));
+  EXPECT_EQ(elem, (std::vector<analysis::Bool::Element>{false, true}));
 }
 
 TEST(TupleLattice, GetBottom) {
@@ -707,7 +711,7 @@ TEST(SharedLattice, JoinVecSingleton) {
 
   auto elem = shared.getBottom();
   EXPECT_TRUE(shared.join(elem, Vec::SingletonElement(1, true)));
-  EXPECT_EQ(*elem, (std::vector{false, true}));
+  EXPECT_EQ(*elem, (std::vector<analysis::Bool::Element>{false, true}));
 }
 
 TEST(SharedLattice, JoinInvertedVecSingleton) {
@@ -717,7 +721,7 @@ TEST(SharedLattice, JoinInvertedVecSingleton) {
 
   auto elem = shared.getBottom();
   EXPECT_TRUE(shared.join(elem, Vec::SingletonElement(1, false)));
-  EXPECT_EQ(*elem, (std::vector{true, false}));
+  EXPECT_EQ(*elem, (std::vector<analysis::Bool::Element>{true, false}));
 }
 
 TEST(StackLattice, GetBottom) {