[Orc] Add a SymbolStringPool data structure for efficient storage and fast

comparison of symbol names.

SymbolStringPool is a thread-safe string pool that will be used in upcoming Orc
APIs to facilitate efficient storage and fast comparison of symbol name strings.

llvm-svn: 319839

1 files changed, 43 insertions, 0 deletions

diff --git a/llvm/unittests/ExecutionEngine/Orc/SymbolStringPoolTest.cpp b/llvm/unittests/ExecutionEngine/Orc/SymbolStringPoolTest.cpp
new file mode 100644
index 00000000000..ac79541d50c
--- /dev/null
+++ b/llvm/unittests/ExecutionEngine/Orc/SymbolStringPoolTest.cpp
@@ -0,0 +1,43 @@
+//===----- SymbolStringPoolTest.cpp - Unit tests for SymbolStringPool -----===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/ExecutionEngine/Orc/SymbolStringPool.h"
+#include "gtest/gtest.h"
+
+using namespace llvm;
+using namespace llvm::orc;
+
+namespace {
+
+TEST(SymbolStringPool, UniquingAndEquality) {
+  SymbolStringPool SP;
+  auto P1 = SP.intern("hello");
+
+  std::string S("hel");
+  S += "lo";
+  auto P2 = SP.intern(S);
+
+  auto P3 = SP.intern("goodbye");
+
+  EXPECT_EQ(P1, P2) << "Failed to unique entries";
+  EXPECT_NE(P1, P3) << "Inequal pooled symbol strings comparing equal";
+}
+
+TEST(SymbolStringPool, ClearDeadEntries) {
+  SymbolStringPool SP;
+  {
+    auto P1 = SP.intern("s1");
+    SP.clearDeadEntries();
+    EXPECT_FALSE(SP.empty()) << "\"s1\" entry in pool should still be retained";
+  }
+  SP.clearDeadEntries();
+  EXPECT_TRUE(SP.empty()) << "pool should be empty";
+}
+
+}