Resolves: fdo#49208 icu string compare is shocking slow

Change-Id: Iee3ab0ebbbb72e88e33dcbe0fcb4df1e4f60c301

1 files changed, 22 insertions, 3 deletions

diff --git a/i18npool/source/breakiterator/breakiterator_unicode.cxx b/i18npool/source/breakiterator/breakiterator_unicode.cxx
index 08a5e6c7feb6..4005780a27d3 100644
--- a/i18npool/source/breakiterator/breakiterator_unicode.cxx
+++ b/i18npool/source/breakiterator/breakiterator_unicode.cxx
@@ -34,6 +34,7 @@
 #include <unicode/udata.h>
 #include <rtl/strbuf.hxx>
 #include <rtl/ustring.hxx>
+#include <string.h>
 
 U_CDECL_BEGIN
 extern const char OpenOffice_dat[];
@@ -94,6 +95,24 @@ class OOoRuleBasedBreakIterator : public RuleBasedBreakIterator {
 
 };
 
+namespace
+{
+    bool isEqual(const UnicodeString &rOne, const rtl::OUString &rOther)
+    {
+        sal_Int32 nLength = rOne.length();
+        if (nLength != rOther.getLength())
+            return false;
+
+        //fdo#49208 operator== is implemented by compareTo etc in icu which is
+        //horrifically slow when all you want to know is that they're the same
+        //or not
+        const UChar *pOne = rOne.getBuffer();
+        // UChar != sal_Unicode in MinGW
+        const UChar *pOther = reinterpret_cast<const UChar *>(rOther.getStr());
+        return memcmp(pOne, pOther, nLength * sizeof(UChar)) == 0;
+    }
+}
+
 // loading ICU breakiterator on demand.
 void SAL_CALL BreakIterator_Unicode::loadICUBreakIterator(const com::sun::star::lang::Locale& rLocale,
         sal_Int16 rBreakType, sal_Int16 rWordType, const sal_Char *rule, const OUString& rText) throw(uno::RuntimeException)
@@ -199,10 +218,10 @@ void SAL_CALL BreakIterator_Unicode::loadICUBreakIterator(const com::sun::star::
         }
     }
 
-    // UChar != sal_Unicode in MinGW
-    const UChar *pText = reinterpret_cast<const UChar *>(rText.getStr());
-    if (newBreak || icuBI->aICUText.compare(pText, rText.getLength()))
+    if (newBreak || !isEqual(icuBI->aICUText, rText))
     {
+        // UChar != sal_Unicode in MinGW
+        const UChar *pText = reinterpret_cast<const UChar *>(rText.getStr());
         icuBI->aICUText=UnicodeString(pText, rText.getLength());
         icuBI->aBreakIterator->setText(icuBI->aICUText);
     }