AK: Move memory stuff (fast memcpy, etc) to a separate header

Move the "fast memcpy" stuff out of StdLibExtras.h and into Memory.h.
This will break a ton of things that were relying on StdLibExtras.h
to include a bunch of other headers. Fix will follow immediately after.

This makes it possible to include StdLibExtras.h from Types.h, which is
the main point of this exercise.

11 files changed, 57 insertions, 49 deletions

diff --git a/AK/JsonParser.cpp b/AK/JsonParser.cpp
index b99bb91bd5..323a0308f6 100644
--- a/AK/JsonParser.cpp
+++ b/AK/JsonParser.cpp
@@ -27,6 +27,7 @@
 #include <AK/JsonArray.h>
 #include <AK/JsonObject.h>
 #include <AK/JsonParser.h>
+#include <AK/Memory.h>
 
 namespace AK {
 
diff --git a/AK/Memory.h b/AK/Memory.h
new file mode 100644
index 0000000000..27b5d2c54b
--- /dev/null
+++ b/AK/Memory.h
@@ -0,0 +1,38 @@
+#pragma once
+
+#include <AK/Types.h>
+
+#if defined(KERNEL) || defined(BOOTSTRAPPER)
+#    include <LibBareMetal/StdLib.h>
+#else
+#    include <stdlib.h>
+#    include <string.h>
+#endif
+
+#if defined(__serenity__) && !defined(KERNEL) && !defined(BOOTSTRAPPER)
+extern "C" void* mmx_memcpy(void* to, const void* from, size_t);
+#endif
+
+[[gnu::always_inline]] inline void fast_u32_copy(u32* dest, const u32* src, size_t count)
+{
+#if defined(__serenity__) && !defined(KERNEL) && !defined(BOOTSTRAPPER)
+    if (count >= 256) {
+        mmx_memcpy(dest, src, count * sizeof(count));
+        return;
+    }
+#endif
+    asm volatile(
+        "rep movsl\n"
+        : "=S"(src), "=D"(dest), "=c"(count)
+        : "S"(src), "D"(dest), "c"(count)
+        : "memory");
+}
+
+[[gnu::always_inline]] inline void fast_u32_fill(u32* dest, u32 value, size_t count)
+{
+    asm volatile(
+        "rep stosl\n"
+        : "=D"(dest), "=c"(count)
+        : "D"(dest), "c"(count), "a"(value)
+        : "memory");
+}
diff --git a/AK/Optional.h b/AK/Optional.h
index 7686bfdd5d..e14f4ecf49 100644
--- a/AK/Optional.h
+++ b/AK/Optional.h
@@ -29,6 +29,7 @@
 #include <AK/Assertions.h>
 #include <AK/Platform.h>
 #include <AK/StdLibExtras.h>
+#include <AK/Types.h>
 
 namespace AK {
 
@@ -157,7 +158,7 @@ private:
         ASSERT(m_has_value);
         return *reinterpret_cast<const T*>(&m_storage);
     }
-    unsigned char m_storage[sizeof(T)] { 0 };
+    u8 m_storage[sizeof(T)] { 0 };
     bool m_has_value { false };
 };
 
diff --git a/AK/SinglyLinkedList.h b/AK/SinglyLinkedList.h
index eec6a1db86..7238b4c76a 100644
--- a/AK/SinglyLinkedList.h
+++ b/AK/SinglyLinkedList.h
@@ -28,6 +28,7 @@
 
 #include <AK/Assertions.h>
 #include <AK/StdLibExtras.h>
+#include <AK/Types.h>
 
 namespace AK {
 
diff --git a/AK/StdLibExtras.h b/AK/StdLibExtras.h
index 7dea07a6e1..c68f3c93e2 100644
--- a/AK/StdLibExtras.h
+++ b/AK/StdLibExtras.h
@@ -26,46 +26,9 @@
 
 #pragma once
 
-#if defined(KERNEL) || defined(BOOTSTRAPPER)
-#    include <LibBareMetal/StdLib.h>
-#else
-#    include <stdlib.h>
-#    include <string.h>
-#endif
-
 #define UNUSED_PARAM(x) (void)x
 
-#include <AK/Types.h>
-
-#if defined(__serenity__) && !defined(KERNEL) && !defined(BOOTSTRAPPER)
-extern "C" void* mmx_memcpy(void* to, const void* from, size_t);
-#endif
-
-[[gnu::always_inline]] inline void fast_u32_copy(u32* dest, const u32* src, size_t count)
-{
-#if defined(__serenity__) && !defined(KERNEL) && !defined(BOOTSTRAPPER)
-    if (count >= 256) {
-        mmx_memcpy(dest, src, count * sizeof(count));
-        return;
-    }
-#endif
-    asm volatile(
-        "rep movsl\n"
-        : "=S"(src), "=D"(dest), "=c"(count)
-        : "S"(src), "D"(dest), "c"(count)
-        : "memory");
-}
-
-[[gnu::always_inline]] inline void fast_u32_fill(u32* dest, u32 value, size_t count)
-{
-    asm volatile(
-        "rep stosl\n"
-        : "=D"(dest), "=c"(count)
-        : "D"(dest), "c"(count), "a"(value)
-        : "memory");
-}
-
-inline constexpr u32 round_up_to_power_of_two(u32 value, u32 power_of_two)
+inline constexpr unsigned round_up_to_power_of_two(unsigned value, unsigned power_of_two)
 {
     return ((value - 1) & ~(power_of_two - 1)) + power_of_two;
 }
diff --git a/AK/String.cpp b/AK/String.cpp
index 3f8fb8b10a..81e6e517a1 100644
--- a/AK/String.cpp
+++ b/AK/String.cpp
@@ -24,6 +24,7 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
+#include <AK/Memory.h>
 #include <AK/StdLibExtras.h>
 #include <AK/String.h>
 #include <AK/StringBuilder.h>
diff --git a/AK/String.h b/AK/String.h
index 0158adb223..c01c771219 100644
--- a/AK/String.h
+++ b/AK/String.h
@@ -252,7 +252,7 @@ inline bool StringView::operator==(const String& string) const
         return false;
     if (m_characters == string.characters())
         return true;
-    return !memcmp(m_characters, string.characters(), m_length);
+    return !__builtin_memcmp(m_characters, string.characters(), m_length);
 }
 
 template<>
diff --git a/AK/StringBuilder.cpp b/AK/StringBuilder.cpp
index 28f89098f5..a047ea70fc 100644
--- a/AK/StringBuilder.cpp
+++ b/AK/StringBuilder.cpp
@@ -24,10 +24,11 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
+#include <AK/Memory.h>
 #include <AK/PrintfImplementation.h>
 #include <AK/StdLibExtras.h>
-#include <AK/StringBuilder.h>
 #include <AK/String.h>
+#include <AK/StringBuilder.h>
 
 namespace AK {
 
diff --git a/AK/StringImpl.cpp b/AK/StringImpl.cpp
index 5f5d2f7752..b47edf0be2 100644
--- a/AK/StringImpl.cpp
+++ b/AK/StringImpl.cpp
@@ -24,10 +24,11 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#include "StringImpl.h"
-#include "HashTable.h"
-#include "StdLibExtras.h"
-#include "kmalloc.h"
+#include <AK/HashTable.h>
+#include <AK/Memory.h>
+#include <AK/StdLibExtras.h>
+#include <AK/StringImpl.h>
+#include <AK/kmalloc.h>
 
 //#define DEBUG_STRINGIMPL
 
diff --git a/AK/StringView.cpp b/AK/StringView.cpp
index 30cf328f4f..ebd179299c 100644
--- a/AK/StringView.cpp
+++ b/AK/StringView.cpp
@@ -25,6 +25,7 @@
  */
 
 #include <AK/ByteBuffer.h>
+#include <AK/Memory.h>
 #include <AK/String.h>
 #include <AK/StringView.h>
 #include <AK/Vector.h>
diff --git a/AK/StringView.h b/AK/StringView.h
index 6d22f2dcde..41e7e7e652 100644
--- a/AK/StringView.h
+++ b/AK/StringView.h
@@ -47,7 +47,7 @@ public:
     }
     [[gnu::always_inline]] inline StringView(const char* cstring)
         : m_characters(cstring)
-        , m_length(cstring ? strlen(cstring) : 0)
+        , m_length(cstring ? __builtin_strlen(cstring) : 0)
     {
     }
 
@@ -105,10 +105,10 @@ public:
             return !cstring;
         if (!cstring)
             return false;
-        size_t other_length = strlen(cstring);
+        size_t other_length = __builtin_strlen(cstring);
         if (m_length != other_length)
             return false;
-        return !memcmp(m_characters, cstring, m_length);
+        return !__builtin_memcmp(m_characters, cstring, m_length);
     }
     bool operator!=(const char* cstring) const
     {
@@ -125,7 +125,7 @@ public:
             return false;
         if (length() != other.length())
             return false;
-        return !memcmp(m_characters, other.m_characters, m_length);
+        return !__builtin_memcmp(m_characters, other.m_characters, m_length);
     }
 
     bool operator!=(const StringView& other) const