Modified for some reviews

Author: tinysun212

include/swift/Runtime/MutexWin32.h

@@ -92,4 +92,4 @@ struct ReadWriteLockPlatformHelper {
 };
 }
 
-#endif
+#endif

stdlib/public/runtime/Errors.cpp

@@ -14,6 +14,12 @@
 //
 //===----------------------------------------------------------------------===//
 
+#if defined(__CYGWIN__) || defined(__ANDROID__) || defined(_MSC_VER)
+#  define SWIFT_SUPPORTS_BACKTRACE_REPORTING 0
+#else
+#  define SWIFT_SUPPORTS_BACKTRACE_REPORTING 1
+#endif
+
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -23,9 +29,6 @@
 #else
 #include <unistd.h>
 #endif
-#if !defined(_MSC_VER)
-#include <pthread.h>
-#endif
 #include <stdarg.h>
 #include "swift/Runtime/Debug.h"
 #include "swift/Runtime/Mutex.h"
@@ -35,7 +38,7 @@
 #if !defined(_MSC_VER)
 #include <cxxabi.h>
 #endif
-#if !defined(__CYGWIN__) && !defined(__ANDROID__) && !defined(_MSC_VER)
+#if SWIFT_SUPPORTS_BACKTRACE_REPORTING
 
 // execinfo.h is not available on Android. Checks in this file ensure that
 // fatalError behaves as expected, but without stack traces.
@@ -57,7 +60,7 @@ enum: uint32_t {
 
 using namespace swift;
 
-#if !defined(__CYGWIN__) && !defined(__ANDROID__) && !defined(_MSC_VER)
+#if SWIFT_SUPPORTS_BACKTRACE_REPORTING
 
 static bool getSymbolNameAddr(llvm::StringRef libraryName, Dl_info dlinfo,
                               std::string &symbolName, uintptr_t &addrOut) {
@@ -203,7 +206,7 @@ reportNow(uint32_t flags, const char *message)
 #ifdef __APPLE__
   asl_log(NULL, NULL, ASL_LEVEL_ERR, "%s", message);
 #endif
-#if !defined(__CYGWIN__) && !defined(__ANDROID__) && !defined(_MSC_VER)
+#if SWIFT_SUPPORTS_BACKTRACE_REPORTING
   if (flags & FatalErrorFlags::ReportBacktrace) {
     fputs("Current stack trace:\n", stderr);
     constexpr unsigned maxSupportedStackDepth = 128;
@@ -225,6 +228,26 @@ void swift::swift_reportError(uint32_t flags,
   reportOnCrash(flags, message);
 }
 
+static int swift_vasprintf(char **strp, const char *fmt, va_list ap) {
+#if defined(_MSC_VER)
+  int len = _vscprintf(fmt, ap);
+  if (len < 0)
+    return -1;
+  char *buffer = reinterpret_cast<char *>(malloc(len + 1));
+  if (!buffer)
+    return -1;
+  int result = vsprintf(*strp, fmt, ap);
+  if (result < 0) {
+    free(buffer);
+    return -1;
+  }
+  *strp = buffer;
+  return result;
+#else
+  return vasprintf(strp, fmt, ap);
+#endif
+}
+
 // Report a fatal error to system console, stderr, and crash logs, then abort.
 LLVM_ATTRIBUTE_NORETURN
 void
@@ -234,13 +257,7 @@ swift::fatalError(uint32_t flags, const char *format, ...)
   va_start(args, format);
 
   char *log;
-#if defined(_MSC_VER)
-  int len = _vscprintf(format, args) + 1;
-  log = reinterpret_cast<char *>(malloc(len));
-  vsprintf(log, format, args);
-#else
-  vasprintf(&log, format, args);
-#endif
+  swift_vasprintf(&log, format, args);
 
   swift_reportError(flags, log);
   abort();

stdlib/public/runtime/HeapObject.cpp

@@ -28,9 +28,6 @@
 #include <cstring>
 #include <cstdio>
 #include <cstdlib>
-#if !defined(_MSC_VER)
-#include <unistd.h>
-#endif
 #include "../SwiftShims/RuntimeShims.h"
 #if SWIFT_OBJC_INTEROP
 # include <objc/NSObject.h>

stdlib/public/runtime/Metadata.cpp

@@ -62,8 +62,22 @@
 using namespace swift;
 using namespace metadataimpl;
 
+static uintptr_t swift_pageSize() {
+#if defined(__APPLE__)
+  return vm_page_size;
+#elif defined(_MSC_VER)
+  SYSTEM_INFO SystemInfo;
+  GetSystemInfo(&SystemInfo);
+  return SystemInfo.dwPageSize;
+#else
+  return sysconf(_SC_PAGESIZE);
+#endif
+}
+
 // allocate memory up to a nearby page boundary
-static void *swift_allocPage(size_t size) {
+static void *swift_allocateMetadataRoundingToPage(size_t size) {
+  const uintptr_t PageSizeMask = SWIFT_LAZY_CONSTANT(swift_pageSize()) - 1;
+  size = (size + PageSizeMask) & ~PageSizeMask;
 #if defined(_MSC_VER)
   auto mem = VirtualAlloc(
       nullptr, size, MEM_TOP_DOWN | MEM_RESERVE | MEM_COMMIT, PAGE_READWRITE);
@@ -76,30 +90,27 @@ static void *swift_allocPage(size_t size) {
   return mem;
 }
 
-// free memory allocated by swift_allocPage()
-// On success, swift_freePage() returns 0, on failure -1
-static int swift_freePage(void *addr, size_t size) {
+// free memory allocated by swift_allocateMetadataRoundingToPage()
+static void swift_freeMetadata(void *addr, size_t size) {
 #if defined(_MSC_VER)
-  return VirtualFree(addr, 0, MEM_RELEASE) == 0 ? -1 : 0;
+  // On success, VirtualFree() returns nonzero, on failure 0 
+  int result = VirtualFree(addr, 0, MEM_RELEASE);
+  if (result == 0)
+    fatalError(/* flags = */ 0, "swift_freePage: VirtualFree() failed");
 #else
-  return munmap(addr, size);
+  // On success, munmap() returns 0, on failure -1
+  int result = munmap(addr, size);
+  if (result != 0)
+    fatalError(/* flags = */ 0, "swift_freePage: munmap() failed");
 #endif
 }
 
 void *MetadataAllocator::alloc(size_t size) {
-#if defined(__APPLE__)
-  const uintptr_t PageSizeMask = vm_page_mask;
-#elif defined(_MSC_VER)
-  SYSTEM_INFO SystemInfo;
-  GetSystemInfo(&SystemInfo);
-  const uintptr_t PageSizeMask = SystemInfo.dwPageSize - 1;
-#else
-  static const uintptr_t PageSizeMask = sysconf(_SC_PAGESIZE) - 1;
-#endif
+  const uintptr_t PageSize = SWIFT_LAZY_CONSTANT(swift_pageSize());
   // If the requested size is a page or larger, map page(s) for it
   // specifically.
-  if (LLVM_UNLIKELY(size > PageSizeMask)) {
-    void *mem = swift_allocPage((size + PageSizeMask) & ~PageSizeMask);
+  if (LLVM_UNLIKELY(size >= PageSize)) {
+    void *mem = swift_allocateMetadataRoundingToPage(size);
     if (!mem)
       crash("unable to allocate memory for metadata cache");
     return mem;
@@ -112,10 +123,11 @@ void *MetadataAllocator::alloc(size_t size) {
 
     // If we wrap over the end of the page, allocate a new page.
     void *allocation = nullptr;
+    const uintptr_t PageSizeMask = PageSize - 1;
     if (LLVM_UNLIKELY(((uintptr_t)next & ~PageSizeMask)
                         != (((uintptr_t)end & ~PageSizeMask)))) {
       // Allocate a new page if we haven't already.
-      allocation = swift_allocPage(PageSizeMask + 1);
+      allocation = swift_allocateMetadataRoundingToPage(PageSize);
 
       if (!allocation)
         crash("unable to allocate memory for metadata cache");
@@ -135,7 +147,7 @@ void *MetadataAllocator::alloc(size_t size) {
     // This potentially causes us to perform multiple mmaps under contention,
     // but it keeps the fast path pristine.
     if (allocation) {
-      swift_freePage(allocation, PageSizeMask + 1);
+      swift_freeMetadata(allocation, PageSize);
     }
   }
 }

stdlib/public/runtime/MetadataLookup.cpp

@@ -34,12 +34,6 @@
 #include <link.h>
 #endif
 
-#if defined(_MSC_VER)
-#include <windows.h>
-#else
-#include <dlfcn.h>
-#endif
-
 using namespace swift;
 using namespace Demangle;
 

stdlib/public/runtime/Once.cpp

@@ -49,6 +49,8 @@ void swift::swift_once(swift_once_t *predicate, void (*fn)(void *)) {
   // process (the token is a word that is atomically incremented from 0 to
   // 1 to 2 during initialization) to work. We should implement our own version
   // that we can rely on to continue to work that way.
+  // The MSVC port also relies on this, because the std::call_once on MSVC
+  // follows the compatible init process.
   // For more information, see rdar://problem/18499385
   std::call_once(*predicate, [fn]() { fn(nullptr); });
 #endif

stdlib/public/runtime/Reflection.mm

@@ -24,9 +24,6 @@
 #include <cstring>
 #include <new>
 #include <string>
-#if !defined(_MSC_VER)
-#include <dlfcn.h>
-#endif
 
 #if SWIFT_OBJC_INTEROP
 #include "swift/Runtime/ObjCBridge.h"

stdlib/public/runtime/SwiftObject.mm

@@ -34,7 +34,7 @@
 #include "../SwiftShims/RuntimeShims.h"
 #include "Private.h"
 #include "swift/Runtime/Debug.h"
-#if !defined(_MSC_VER)
+#if SWIFT_OBJC_INTEROP
 #include <dlfcn.h>
 #endif
 #include <stdio.h>

stdlib/public/stubs/LibcShims.cpp

@@ -57,16 +57,28 @@ int swift::_swift_stdlib_memcmp(const void *s1, const void *s2,
 
 __swift_ssize_t
 swift::_swift_stdlib_read(int fd, void *buf, __swift_size_t nbyte) {
+#if defined(_MSC_VER)
+  return _read(fd, buf, nbyte);
+#else
   return read(fd, buf, nbyte);
+#endif
 }
 
 __swift_ssize_t
 swift::_swift_stdlib_write(int fd, const void *buf, __swift_size_t nbyte) {
+#if defined(_MSC_VER)
+  return _write(fd, buf, nbyte);
+#else
   return write(fd, buf, nbyte);
+#endif
 }
 
 int swift::_swift_stdlib_close(int fd) {
+#if defined(_MSC_VER)
+  return _close(fd);
+#else
   return close(fd);
+#endif
 }
 
 #if defined(__APPLE__)

stdlib/public/stubs/Stubs.cpp

@@ -265,7 +265,7 @@ ssize_t swift::swift_stdlib_readLine_stdin(char **LinePtr) {
   if (LinePtr == nullptr)
     return -1;
 
-  int Capacity = 0;
+  ssize_t Capacity = 0;
   ssize_t Pos = 0;
   char *ReadBuf = nullptr;