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authorLiang Qi <liang.qi@qt.io>2017-09-26 16:08:55 +0200
committerLiang Qi <liang.qi@qt.io>2017-09-26 16:14:54 +0200
commitaadfe7d634de04519102c5827ca885dc2e2199c9 (patch)
treed92db346ca95332b177036a53f1f6beb2e24fb74 /src/corelib/tools/qstring.cpp
parent4b6c1448047362b8c38d265e6414f0e3e59b8d37 (diff)
parenta732e16d5fd9dbf8a0289fec9f948b12e9ba2c19 (diff)
Merge remote-tracking branch 'origin/5.10' into dev
Conflicts: src/gui/kernel/qguiapplication.cpp src/platformsupport/input/libinput/qlibinputpointer.cpp src/plugins/platforminputcontexts/ibus/qibusplatforminputcontext.h src/plugins/platforms/cocoa/qcocoawindow.h src/testlib/qtestsystem.h Change-Id: I5975ffb3261c2dd82fe02ec4e57df7c0950226c5
Diffstat (limited to 'src/corelib/tools/qstring.cpp')
-rw-r--r--src/corelib/tools/qstring.cpp38
1 files changed, 38 insertions, 0 deletions
diff --git a/src/corelib/tools/qstring.cpp b/src/corelib/tools/qstring.cpp
index ea157a23d0..eeeff280ff 100644
--- a/src/corelib/tools/qstring.cpp
+++ b/src/corelib/tools/qstring.cpp
@@ -72,6 +72,7 @@
#include <stdlib.h>
#include <stdio.h>
#include <stdarg.h>
+#include <wchar.h>
#include "qchar.cpp"
#include "qstringmatcher.cpp"
@@ -159,6 +160,43 @@ static inline bool qt_ends_with(QStringView haystack, QStringView needle, Qt::Ca
static inline bool qt_ends_with(QStringView haystack, QLatin1String needle, Qt::CaseSensitivity cs);
static inline bool qt_ends_with(QStringView haystack, QChar needle, Qt::CaseSensitivity cs);
+qssize_t qustrlen(const ushort *str) Q_DECL_NOTHROW
+{
+ qssize_t result = 0;
+
+#ifdef __SSE2__
+ // progress until we get an aligned pointer
+ const ushort *ptr = str;
+ while (*ptr && quintptr(ptr) % 16)
+ ++ptr;
+ if (*ptr == 0)
+ return ptr - str;
+
+ // load 16 bytes and see if we have a null
+ // (aligned loads can never segfault)
+ int mask;
+ const __m128i zeroes = _mm_setzero_si128();
+ do {
+ __m128i data = _mm_load_si128(reinterpret_cast<const __m128i *>(ptr));
+ ptr += 8;
+
+ __m128i comparison = _mm_cmpeq_epi16(data, zeroes);
+ mask = _mm_movemask_epi8(comparison);
+ } while (mask == 0);
+
+ // found a null
+ uint idx = qCountTrailingZeroBits(quint32(mask));
+ return ptr - str - 8 + idx / 2;
+#endif
+
+ if (sizeof(wchar_t) == sizeof(ushort))
+ return wcslen(reinterpret_cast<const wchar_t *>(str));
+
+ while (*str++)
+ ++result;
+ return result;
+}
+
#if defined(Q_COMPILER_LAMBDA) && !defined(__OPTIMIZE_SIZE__)
namespace {
template <uint MaxCount> struct UnrollTailLoop