[llvm-commits] [llvm] r91817 - in /llvm/trunk: include/llvm/ADT/StringRef.h unittests/ADT/StringRefTest.cpp

[Eli Friedman]

Author: efriedma
Date: Mon Dec 21 00:49:24 2009
New Revision: 91817

URL: http://llvm.org/viewvc/llvm-project?rev=91817&view=rev
Log:
Change StringRef::startswith and StringRef::endswith to versions which are a
bit more verbose, but optimize to much shorter code.


Modified:
    llvm/trunk/include/llvm/ADT/StringRef.h
    llvm/trunk/unittests/ADT/StringRefTest.cpp

Modified: llvm/trunk/include/llvm/ADT/StringRef.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/ADT/StringRef.h?rev=91817&r1=91816&r2=91817&view=diff

==============================================================================
--- llvm/trunk/include/llvm/ADT/StringRef.h (original)
+++ llvm/trunk/include/llvm/ADT/StringRef.h Mon Dec 21 00:49:24 2009
@@ -159,12 +159,14 @@
 
     /// startswith - Check if this string starts with the given \arg Prefix.
     bool startswith(StringRef Prefix) const {
-      return substr(0, Prefix.Length).equals(Prefix);
+      return Length >= Prefix.Length &&
+             memcmp(Data, Prefix.Data, Prefix.Length) == 0;
     }
 
     /// endswith - Check if this string ends with the given \arg Suffix.
     bool endswith(StringRef Suffix) const {
-      return slice(size() - Suffix.Length, size()).equals(Suffix);
+      return Length >= Suffix.Length &&
+             memcmp(end() - Suffix.Length, Suffix.Data, Suffix.Length) == 0;
     }
 
     /// @}

Modified: llvm/trunk/unittests/ADT/StringRefTest.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/unittests/ADT/StringRefTest.cpp?rev=91817&r1=91816&r2=91817&view=diff

==============================================================================
--- llvm/trunk/unittests/ADT/StringRefTest.cpp (original)
+++ llvm/trunk/unittests/ADT/StringRefTest.cpp Mon Dec 21 00:49:24 2009
@@ -198,6 +198,14 @@
   EXPECT_FALSE(Str.startswith("hi"));
 }
 
+TEST(StringRefTest, EndsWith) {
+  StringRef Str("hello");
+  EXPECT_TRUE(Str.endswith("lo"));
+  EXPECT_FALSE(Str.endswith("helloworld"));
+  EXPECT_FALSE(Str.endswith("worldhello"));
+  EXPECT_FALSE(Str.endswith("so"));
+}
+
 TEST(StringRefTest, Find) {
   StringRef Str("hello");
   EXPECT_EQ(2U, Str.find('l'));