[UCRT] Import Microsoft.Windows.SDK.CRTSource version 10.0.22621.3

Imported from https://www.nuget.org/packages/Microsoft.Windows.SDK.CRTSource/10.0.22621.3
License: MIT

sdk/lib/ucrt/heap/msize.cpp

@@ -0,0 +1,42 @@
+//
+// msize.cpp
+//
+//      Copyright (c) Microsoft Corporation. All rights reserved.
+//
+// Implementation of msize().
+//
+#include <corecrt_internal.h>
+#include <malloc.h>
+
+
+
+// This function implements the logic of _msize().  It is called only in the
+// Release CRT.  The Debug CRT has its own implementation of this function.
+//
+// This function must be marked noinline, otherwise _msize and
+// _msize_base will have identical COMDATs, and the linker will fold
+// them when calling one from the CRT. This is necessary because _msize
+// needs to support users patching in custom implementations.
+extern "C" __declspec(noinline) size_t __cdecl _msize_base(void* const block) noexcept
+{
+    // Validation section
+    _VALIDATE_RETURN(block != nullptr, EINVAL, static_cast<size_t>(-1));
+
+    return static_cast<size_t>(HeapSize(__acrt_heap, 0, block));
+}
+
+// Calculates the size of the specified block in the heap.  'block' must be a
+// pointer to a valid block of heap-allocated memory (it must not be nullptr).
+//
+// This function supports patching and therefore must be marked noinline.
+// Both _msize_dbg and _msize_base must also be marked noinline
+// to prevent identical COMDAT folding from substituting calls to _msize
+// with either other function or vice versa.
+extern "C" _CRT_HYBRIDPATCHABLE __declspec(noinline) size_t __cdecl _msize(void* const block)
+{
+    #ifdef _DEBUG
+    return _msize_dbg(block, _NORMAL_BLOCK);
+    #else
+    return _msize_base(block);
+    #endif
+}