Move GCC/x86 assembler instructions into a single common file; begin work on supporting MinGW as a secondary Win32 build environment.

stepmania/src/archutils/Unix/arch_setup.h

@@ -5,39 +5,9 @@
 #include <stdint.h>
 #endif
 
-#if defined(CPU_X86)
-
-inline uint32_t ArchSwap32( uint32_t n )
-{
-	asm(
-		"xchg %b0, %h0\n"
-		"rorl $16, %0\n"
-		"xchg %b0, %h0":
-		"=q" (n): "0" (n) );
-	return n;
-}
-
-inline uint32_t ArchSwap24( uint32_t n )
-{
-	asm(
-		"xchg %b0, %h0\n"
-		"rorl $16, %0\n"
-		"xchg %b0, %h0\n"
-		"shrl $8, %0\n":
-		"=q" (n): "0" (n) );
-	return n;
-}
-
-inline uint16_t ArchSwap16( uint16_t n )
-{
-	asm(
-		"xchg %b0, %h0\n":
-		"=q" (n): "0" (n) );
-	return n;
-}
-
-#define HAVE_BYTE_SWAPS
-#endif
+// XXX: Maybe we should make sure we're using GCC first?
+// But if not, then what DO we use?
+#include "archutils/Common/gcc_byte_swaps.h"
 
 #endif