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-rw-r--r--absl/container/internal/hash_function_defaults.h5
-rw-r--r--absl/container/internal/raw_hash_set.h17
-rw-r--r--absl/container/internal/raw_hash_set_test.cc4
3 files changed, 15 insertions, 11 deletions
diff --git a/absl/container/internal/hash_function_defaults.h b/absl/container/internal/hash_function_defaults.h
index dd6cd8f537fd..1f0d794d9663 100644
--- a/absl/container/internal/hash_function_defaults.h
+++ b/absl/container/internal/hash_function_defaults.h
@@ -83,11 +83,6 @@ struct StringHashEq {
     }
   };
 };
-
-#if defined(HAS_GLOBAL_STRING)
-template <>
-struct HashEq<std::string> : StringHashEq {};
-#endif
 template <>
 struct HashEq<std::string> : StringHashEq {};
 template <>
diff --git a/absl/container/internal/raw_hash_set.h b/absl/container/internal/raw_hash_set.h
index 0c0e5906d206..70da90f79a4f 100644
--- a/absl/container/internal/raw_hash_set.h
+++ b/absl/container/internal/raw_hash_set.h
@@ -1330,8 +1330,7 @@ class raw_hash_set {
   void rehash(size_t n) {
     if (n == 0 && capacity_ == 0) return;
     if (n == 0 && size_ == 0) return destroy_slots();
-    auto m = NormalizeCapacity(std::max(
-        n, static_cast<size_t>(std::ceil(size() / kMaxLoadFactor))));
+    auto m = NormalizeCapacity(std::max(n, NumSlotsFast(size())));
     // n == 0 unconditionally rehashes as per the standard.
     if (n == 0 || m > capacity_) {
       resize(m);
@@ -1339,7 +1338,7 @@ class raw_hash_set {
   }
 
   void reserve(size_t n) {
-    rehash(static_cast<size_t>(std::ceil(n / kMaxLoadFactor)));
+    rehash(NumSlotsFast(n));
   }
 
   // Extension API: support for heterogeneous keys.
@@ -1518,6 +1517,13 @@ class raw_hash_set {
     slot_type&& slot;
   };
 
+  // Computes std::ceil(n / kMaxLoadFactor). Faster than calling std::ceil.
+  static inline size_t NumSlotsFast(size_t n) {
+    return static_cast<size_t>(
+        (n * kMaxLoadFactorDenominator + (kMaxLoadFactorNumerator - 1)) /
+        kMaxLoadFactorNumerator);
+  }
+
   // "erases" the object from the container, except that it doesn't actually
   // destroy the object. It only updates all the metadata of the class.
   // This can be used in conjunction with Policy::transfer to move the object to
@@ -1825,7 +1831,10 @@ class raw_hash_set {
   }
 
   // On average each group has 2 empty slot (for the vectorized case).
-  static constexpr float kMaxLoadFactor = 14.0 / 16.0;
+  static constexpr int64_t kMaxLoadFactorNumerator = 14;
+  static constexpr int64_t kMaxLoadFactorDenominator = 16;
+  static constexpr float kMaxLoadFactor =
+      1.0 * kMaxLoadFactorNumerator / kMaxLoadFactorDenominator;
 
   // TODO(alkis): Investigate removing some of these fields:
   // - ctrl/slots can be derived from each other
diff --git a/absl/container/internal/raw_hash_set_test.cc b/absl/container/internal/raw_hash_set_test.cc
index f59a19b4a62d..cd33a3acb917 100644
--- a/absl/container/internal/raw_hash_set_test.cc
+++ b/absl/container/internal/raw_hash_set_test.cc
@@ -1916,7 +1916,7 @@ TEST(Table, EffectiveLoadFactorInts) {
 }
 
 // Confirm that we assert if we try to erase() end().
-TEST(Table, EraseOfEndAsserts) {
+TEST(TableDeathTest, EraseOfEndAsserts) {
   // Use an assert with side-effects to figure out if they are actually enabled.
   bool assert_enabled = false;
   assert([&]() {
@@ -1928,7 +1928,7 @@ TEST(Table, EraseOfEndAsserts) {
   IntTable t;
   // Extra simple "regexp" as regexp support is highly varied across platforms.
   constexpr char kDeathMsg[] = "it != end";
-  EXPECT_DEATH(t.erase(t.end()), kDeathMsg);
+  EXPECT_DEATH_IF_SUPPORTED(t.erase(t.end()), kDeathMsg);
 }
 
 #ifdef ADDRESS_SANITIZER