diff options
| -rw-r--r-- | include/llvm/ADT/StringRef.h | 4 | ||||
| -rw-r--r-- | lib/Support/StringRef.cpp | 7 | ||||
| -rw-r--r-- | unittests/ADT/StringRefTest.cpp | 19 |
3 files changed, 30 insertions, 0 deletions
diff --git a/include/llvm/ADT/StringRef.h b/include/llvm/ADT/StringRef.h index 53ebe6a..a2bb7fe 100644 --- a/include/llvm/ADT/StringRef.h +++ b/include/llvm/ADT/StringRef.h @@ -19,6 +19,7 @@ namespace llvm { template<typename T> class SmallVectorImpl; class APInt; + class hash_code; /// StringRef - Represent a constant reference to a string, i.e. a character /// array and a length, which need not be null terminated. @@ -490,6 +491,9 @@ namespace llvm { /// @} + /// \brief Compute a hash_code for a StringRef. + hash_code hash_value(StringRef S); + // StringRefs can be treated like a POD type. template <typename T> struct isPodLike; template <> struct isPodLike<StringRef> { static const bool value = true; }; diff --git a/lib/Support/StringRef.cpp b/lib/Support/StringRef.cpp index 44e7325..1c28bf8 100644 --- a/lib/Support/StringRef.cpp +++ b/lib/Support/StringRef.cpp @@ -10,6 +10,7 @@ #include "llvm/ADT/StringRef.h" #include "llvm/ADT/APInt.h" #include "llvm/ADT/OwningPtr.h" +#include "llvm/ADT/Hashing.h" #include "llvm/ADT/edit_distance.h" #include <bitset> @@ -447,3 +448,9 @@ bool StringRef::getAsInteger(unsigned Radix, APInt &Result) const { return false; } + + +// Implementation of StringRef hashing. +hash_code llvm::hash_value(StringRef S) { + return hash_combine_range(S.begin(), S.end()); +} diff --git a/unittests/ADT/StringRefTest.cpp b/unittests/ADT/StringRefTest.cpp index d910843..b2f6fdc 100644 --- a/unittests/ADT/StringRefTest.cpp +++ b/unittests/ADT/StringRefTest.cpp @@ -9,6 +9,7 @@ #include "gtest/gtest.h" #include "llvm/ADT/StringRef.h" +#include "llvm/ADT/Hashing.h" #include "llvm/ADT/SmallVector.h" #include "llvm/Support/raw_ostream.h" using namespace llvm; @@ -291,4 +292,22 @@ TEST(StringRefTest, Misc) { EXPECT_EQ("hello", OS.str()); } +TEST(StringRefTest, Hashing) { + EXPECT_EQ(hash_value(std::string()), hash_value(StringRef())); + EXPECT_EQ(hash_value(std::string()), hash_value(StringRef(""))); + std::string S = "hello world"; + hash_code H = hash_value(S); + EXPECT_EQ(H, hash_value(StringRef("hello world"))); + EXPECT_EQ(H, hash_value(StringRef(S))); + EXPECT_NE(H, hash_value(StringRef("hello worl"))); + EXPECT_EQ(hash_value(std::string("hello worl")), + hash_value(StringRef("hello worl"))); + EXPECT_NE(H, hash_value(StringRef("hello world "))); + EXPECT_EQ(hash_value(std::string("hello world ")), + hash_value(StringRef("hello world "))); + EXPECT_EQ(H, hash_value(StringRef("hello world\0"))); + EXPECT_NE(hash_value(std::string("ello worl")), + hash_value(StringRef("hello world").slice(1, -1))); +} + } // end anonymous namespace |