[K/N] Move memmem from Porting.h to KString.cpp ^KT-59008

kotlin-native/runtime/src/main/cpp/KString.cpp

@@ -111,6 +111,16 @@ int threeWayCompare(T a, T b) {
     return (a == b) ? 0 : (a < b ? -1 : 1);
 }
 
+#if KONAN_WINDOWS
+void* memmem(const void *big, size_t bigLen, const void *little, size_t littleLen) {
+  for (size_t i = 0; i + littleLen <= bigLen; ++i) {
+    void* pos = ((char*)big) + i;
+    if (memcmp(little, pos, littleLen) == 0) return pos;
+  }
+  return nullptr;
+}
+#endif
+
 } // namespace
 
 extern "C" {
@@ -388,7 +398,9 @@ KInt Kotlin_String_lastIndexOfChar(KString thiz, KChar ch, KInt fromIndex) {
   return -1;
 }
 
-// TODO: or code up Knuth-Moris-Pratt.
+// TODO: or code up Knuth-Moris-Pratt,
+//       or use std::search with std::boyer_moore_searcher:
+//       https://en.cppreference.com/w/cpp/algorithm/search
 KInt Kotlin_String_indexOfString(KString thiz, KString other, KInt fromIndex) {
   if (fromIndex < 0) {
     fromIndex = 0;
@@ -407,7 +419,7 @@ KInt Kotlin_String_indexOfString(KString thiz, KString other, KInt fromIndex) {
   const KChar* otherRaw = CharArrayAddressOfElementAt(other, 0);
   const auto otherSize = other->count_ * sizeof(KChar);
   while (true) {
-    void* result = konan::memmem(thizRaw + fromIndex, (thiz->count_ - fromIndex) * sizeof(KChar),
+    void* result = memmem(thizRaw + fromIndex, (thiz->count_ - fromIndex) * sizeof(KChar),
                                  otherRaw, otherSize);
     if (result == nullptr) return -1;
     auto byteIndex = reinterpret_cast<intptr_t>(result) - reinterpret_cast<intptr_t>(thizRaw);

kotlin-native/runtime/src/main/cpp/Porting.cpp

@@ -251,22 +251,6 @@ NO_EXTERNAL_CALLS_CHECK int currentThreadId() {
 #endif
 }
 
-// String/byte operations.
-// memcpy/memmove are not here intentionally, as frequently implemented/optimized
-// by C compiler.
-void* memmem(const void *big, size_t bigLen, const void *little, size_t littleLen) {
-#if KONAN_NO_MEMMEM
-  for (size_t i = 0; i + littleLen <= bigLen; ++i) {
-    void* pos = ((char*)big) + i;
-    if (::memcmp(little, pos, littleLen) == 0) return pos;
-  }
-  return nullptr;
-#else
-  return ::memmem(big, bigLen, little, littleLen);
-#endif
-
-}
-
 // Time operations.
 using namespace std::chrono;
 

kotlin-native/runtime/src/main/cpp/Porting.h

@@ -40,11 +40,6 @@ void onThreadExit(void (*destructor)(void*), void* destructorParameter);
 bool isOnThreadExitNotSetOrAlreadyStarted();
 int currentThreadId();
 
-// String/byte operations.
-// memcpy/memmove/memcmp are not here intentionally, as frequently implemented/optimized
-// by C compiler.
-void* memmem(const void *big, size_t bigLen, const void *little, size_t littleLen);
-
 // Time operations.
 uint64_t getTimeMillis();
 uint64_t getTimeMicros();

native/utils/src/org/jetbrains/kotlin/konan/target/ClangArgs.kt

@@ -43,7 +43,6 @@ sealed class ClangArgs(
                     "WINDOWS".takeIf { target.family == Family.MINGW },
                     "MACOSX".takeIf { target.family == Family.OSX },
 
-                    "NO_MEMMEM".takeUnless { target.suportsMemMem() },
                     "NO_64BIT_ATOMIC".takeUnless { target.supports64BitAtomics() },
                     "NO_UNALIGNED_ACCESS".takeUnless { target.supportsUnalignedAccess() },
                     "FORBID_BUILTIN_MUL_OVERFLOW".takeUnless { target.supports64BitMulOverflow() },

native/utils/src/org/jetbrains/kotlin/konan/target/KonanTargetExtenstions.kt

@@ -99,14 +99,6 @@ fun KonanTarget.supportsExceptions(): Boolean = when(this) {
     else -> true
 }
 
-fun KonanTarget.suportsMemMem(): Boolean = when (this) {
-    is KonanTarget.WASM32 -> false
-    is KonanTarget.MINGW_X86 -> false
-    is KonanTarget.MINGW_X64 -> false
-    is KonanTarget.ZEPHYR -> false
-    else -> true
-}
-
 fun KonanTarget.supportsObjcInterop(): Boolean = family.isAppleFamily
 fun KonanTarget.hasFoundationFramework(): Boolean = family.isAppleFamily
 fun KonanTarget.hasUIKitFramework(): Boolean = family == Family.IOS || family == Family.TVOS