From 5db7e9f9370a5e04949846cc68eeb13e2c1db187 Mon Sep 17 00:00:00 2001
From: PJ Reiniger <pj.reiniger@gmail.com>
Date: Tue, 3 May 2022 22:16:10 -0400
Subject: [PATCH 13/28] Extra collections features

---
 llvm/include/llvm/ADT/StringMap.h | 103 +++++++++++++++++++++++++++++-
 llvm/lib/Support/raw_ostream.cpp  |   8 +++
 2 files changed, 110 insertions(+), 1 deletion(-)

diff --git a/llvm/include/llvm/ADT/StringMap.h b/llvm/include/llvm/ADT/StringMap.h
index 8747cdb35..16f13f048 100644
--- a/llvm/include/llvm/ADT/StringMap.h
+++ b/llvm/include/llvm/ADT/StringMap.h
@@ -42,7 +42,7 @@ protected:
 
 protected:
   explicit StringMapImpl(unsigned itemSize) : ItemSize(itemSize) {}
-  StringMapImpl(StringMapImpl &&RHS)
+  StringMapImpl(StringMapImpl &&RHS) noexcept
       : TheTable(RHS.TheTable), NumBuckets(RHS.NumBuckets),
         NumItems(RHS.NumItems), NumTombstones(RHS.NumTombstones),
         ItemSize(RHS.ItemSize) {
@@ -420,11 +420,27 @@ public:
     return Tmp;
   }
 
+  DerivedTy &operator--() { // Predecrement
+    --Ptr;
+    ReversePastEmptyBuckets();
+    return static_cast<DerivedTy &>(*this);
+  }
+
+  DerivedTy operator--(int) { // Post-decrement
+    DerivedTy Tmp(Ptr);
+    --*this;
+    return Tmp;
+  }
+
 private:
   void AdvancePastEmptyBuckets() {
     while (*Ptr == nullptr || *Ptr == StringMapImpl::getTombstoneVal())
       ++Ptr;
   }
+  void ReversePastEmptyBuckets() {
+    while (*Ptr == nullptr || *Ptr == StringMapImpl::getTombstoneVal())
+      --Ptr;
+  }
 };
 
 template <typename ValueTy>
@@ -483,6 +499,91 @@ public:
   std::string_view operator*() const { return this->wrapped()->getKey(); }
 };
 
+template <typename ValueTy>
+bool operator==(const StringMap<ValueTy>& lhs, const StringMap<ValueTy>& rhs) {
+  // same instance?
+  if (&lhs == &rhs) return true;
+
+  // first check that sizes are identical
+  if (lhs.size() != rhs.size()) return false;
+
+  // copy into vectors and sort by key
+  SmallVector<StringMapConstIterator<ValueTy>, 16> lhs_items;
+  lhs_items.reserve(lhs.size());
+  for (auto i = lhs.begin(), end = lhs.end(); i != end; ++i)
+    lhs_items.push_back(i);
+  std::sort(lhs_items.begin(), lhs_items.end(),
+            [](const StringMapConstIterator<ValueTy>& a,
+               const StringMapConstIterator<ValueTy>& b) {
+              return a->getKey() < b->getKey();
+            });
+
+  SmallVector<StringMapConstIterator<ValueTy>, 16> rhs_items;
+  rhs_items.reserve(rhs.size());
+  for (auto i = rhs.begin(), end = rhs.end(); i != end; ++i)
+    rhs_items.push_back(i);
+  std::sort(rhs_items.begin(), rhs_items.end(),
+            [](const StringMapConstIterator<ValueTy>& a,
+               const StringMapConstIterator<ValueTy>& b) {
+              return a->getKey() < b->getKey();
+            });
+
+  // compare vector keys and values
+  for (auto a = lhs_items.begin(), b = rhs_items.begin(),
+            aend = lhs_items.end(), bend = rhs_items.end();
+       a != aend && b != bend; ++a, ++b) {
+    if ((*a)->first() != (*b)->first() || (*a)->second != (*b)->second)
+      return false;
+  }
+  return true;
+}
+
+template <typename ValueTy>
+inline bool operator!=(const StringMap<ValueTy>& lhs,
+                       const StringMap<ValueTy>& rhs) {
+  return !(lhs == rhs);
+}
+
+template <typename ValueTy>
+bool operator<(const StringMap<ValueTy>& lhs, const StringMap<ValueTy>& rhs) {
+  // same instance?
+  if (&lhs == &rhs) return false;
+
+  // copy into vectors and sort by key
+  SmallVector<std::string_view, 16> lhs_keys;
+  lhs_keys.reserve(lhs.size());
+  for (auto i = lhs.begin(), end = lhs.end(); i != end; ++i)
+    lhs_keys.push_back(i->getKey());
+  std::sort(lhs_keys.begin(), lhs_keys.end());
+
+  SmallVector<std::string_view, 16> rhs_keys;
+  rhs_keys.reserve(rhs.size());
+  for (auto i = rhs.begin(), end = rhs.end(); i != end; ++i)
+    rhs_keys.push_back(i->getKey());
+  std::sort(rhs_keys.begin(), rhs_keys.end());
+
+  // use std::vector comparison
+  return lhs_keys < rhs_keys;
+}
+
+template <typename ValueTy>
+inline bool operator<=(const StringMap<ValueTy>& lhs,
+                       const StringMap<ValueTy>& rhs) {
+  return !(rhs < lhs);
+}
+
+template <typename ValueTy>
+inline bool operator>(const StringMap<ValueTy>& lhs,
+                      const StringMap<ValueTy>& rhs) {
+  return !(lhs <= rhs);
+}
+
+template <typename ValueTy>
+inline bool operator>=(const StringMap<ValueTy>& lhs,
+                       const StringMap<ValueTy>& rhs) {
+  return !(lhs < rhs);
+}
+
 } // end namespace llvm
 
 #endif // LLVM_ADT_STRINGMAP_H
diff --git a/llvm/lib/Support/raw_ostream.cpp b/llvm/lib/Support/raw_ostream.cpp
index 36faf744c..95152849c 100644
--- a/llvm/lib/Support/raw_ostream.cpp
+++ b/llvm/lib/Support/raw_ostream.cpp
@@ -76,6 +76,14 @@ constexpr raw_ostream::Colors raw_ostream::WHITE;
 constexpr raw_ostream::Colors raw_ostream::SAVEDCOLOR;
 constexpr raw_ostream::Colors raw_ostream::RESET;
 
+namespace {
+// Find the length of an array.
+template <class T, std::size_t N>
+constexpr inline size_t array_lengthof(T (&)[N]) {
+  return N;
+}
+}  // namespace
+
 raw_ostream::~raw_ostream() {
   // raw_ostream's subclasses should take care to flush the buffer
   // in their destructors.