Add EndianSwap function using platform intrinsics

renderdoc/os/os_specific.h

@@ -422,6 +422,7 @@ inline uint64_t CountLeadingZeroes(uint64_t value);
 // std::string
 // OS_DEBUG_BREAK() - instruction that debugbreaks the debugger - define instead of function to
 // preserve callstacks
+// EndianSwapXX() for XX = 16, 32, 64
 
 #if ENABLED(RDOC_WIN32)
 #include "win32/win32_specific.h"
@@ -430,3 +431,66 @@ inline uint64_t CountLeadingZeroes(uint64_t value);
 #else
 #error Undefined Platform!
 #endif
+
+inline uint64_t EndianSwap(uint64_t t)
+{
+  return EndianSwap64(t);
+}
+
+inline uint32_t EndianSwap(uint32_t t)
+{
+  return EndianSwap32(t);
+}
+
+inline uint16_t EndianSwap(uint16_t t)
+{
+  return EndianSwap16(t);
+}
+
+inline int64_t EndianSwap(int64_t t)
+{
+  return (int64_t)EndianSwap(uint64_t(t));
+}
+
+inline int32_t EndianSwap(int32_t t)
+{
+  return (int32_t)EndianSwap(uint32_t(t));
+}
+
+inline int16_t EndianSwap(int16_t t)
+{
+  return (int16_t)EndianSwap(uint16_t(t));
+}
+
+inline double EndianSwap(double t)
+{
+  uint64_t u;
+  memcpy(&u, &t, sizeof(t));
+  u = EndianSwap(u);
+  memcpy(&t, &u, sizeof(t));
+  return t;
+}
+
+inline float EndianSwap(float t)
+{
+  uint32_t u;
+  memcpy(&u, &t, sizeof(t));
+  u = EndianSwap(u);
+  memcpy(&t, &u, sizeof(t));
+  return t;
+}
+
+inline char EndianSwap(char t)
+{
+  return t;
+}
+
+inline byte EndianSwap(byte t)
+{
+  return t;
+}
+
+inline bool EndianSwap(bool t)
+{
+  return t;
+}

renderdoc/os/posix/posix_specific.h

@@ -32,6 +32,21 @@
 
 #define OS_DEBUG_BREAK() raise(SIGTRAP)
 
+#if ENABLED(RDOC_APPLE)
+
+#include <libkern/OSByteOrder.h>
+#define EndianSwap16(x) OSSwapInt16(x)
+#define EndianSwap32(x) OSSwapInt32(x)
+#define EndianSwap64(x) OSSwapInt64(x)
+
+#else
+
+#define EndianSwap16(x) __builtin_bswap16(x)
+#define EndianSwap32(x) __builtin_bswap32(x)
+#define EndianSwap64(x) __builtin_bswap64(x)
+
+#endif
+
 struct EmbeddedResourceType
 {
   EmbeddedResourceType(const unsigned char *b, int l) : base(b), len(l) {}

renderdoc/os/win32/win32_specific.h

@@ -29,6 +29,7 @@
 #define NOMINMAX
 
 #include <intrin.h>
+#include <stdlib.h>
 #include <windows.h>
 #include "data/resource.h"
 
@@ -36,6 +37,10 @@
 
 #define OS_DEBUG_BREAK() __debugbreak()
 
+#define EndianSwap16(x) _byteswap_ushort(x)
+#define EndianSwap32(x) _byteswap_ulong(x)
+#define EndianSwap64(x) _byteswap_uint64(x)
+
 #define EmbeddedResourceType int
 #define EmbeddedResource(filename) CONCAT(RESOURCE_, filename)