os_timer.c
author bjarni
Sat, 12 Aug 2006 10:41:29 +0000
changeset 4251 e8f69de723e1
parent 3407 150783e37553
child 5363 11cbdbe10de6
permissions -rw-r--r--
(svn r5853) -Fix: [elrails] FS#178 Electric Trains can leave Conventional Depot
now the user will get an error if he tries to start the train and the status bar will say "no power" instead of "stopped"
Electric trains already driving in and out of non-electrified depots will still do so, but you can't start new ones
/* $Id$ */

#include "stdafx.h"

#undef RDTSC_AVAILABLE

/* rdtsc for MSC_VER, uses simple inline assembly, or _rdtsc
 * from external win64.asm because VS2005 does not support inline assembly */
#if defined(_MSC_VER) && !defined(RDTSC_AVAILABLE)
# if defined (_M_AMD64)
extern uint64 _rdtsc(void);
#	else
uint64 _declspec(naked) _rdtsc(void)
{
	_asm {
		rdtsc
		ret
	}
}
# endif
# define RDTSC_AVAILABLE
#endif

/* rdtsc for OS/2. Hopefully this works, who knows */
#if defined (__WATCOMC__) && !defined(RDTSC_AVAILABLE)
unsigned __int64 _rdtsc( void);
# pragma aux _rdtsc = 0x0F 0x31 value [edx eax] parm nomemory modify exact [edx eax] nomemory;
# define RDTSC_AVAILABLE
#endif

/* rdtsc for all other *nix-en (hopefully). Use GCC syntax */
#if defined(__i386__) || defined(__x86_64__) && !defined(RDTSC_AVAILABLE)
uint64 _rdtsc(void)
{
	uint32 high, low;
	__asm__ __volatile__ ("rdtsc" : "=a" (low), "=d" (high));
	return ((uint64)high << 32) | low;
}
# define RDTSC_AVAILABLE
#endif

/* rdtsc for PPC which has this not */
#if defined(__POWERPC__) && !defined(RDTSC_AVAILABLE)
uint64 _rdtsc(void)
{
	uint32 high = 0, high2 = 0, low;
	/* PPC does not have rdtsc, so we cheat by reading the two 32-bit time-counters
	 * it has, 'Move From Time Base (Upper)'. Since these are two reads, in the
	 * very unlikely event that the lower part overflows to the upper part while we
	 * read it; we double-check and reread the registers */
	asm volatile (
				  "mftbu %0\n"
				  "mftb %1\n"
				  "mftbu %2\n"
				  "cmpw %3,%4\n"
				  "bne- $-16\n"
				  : "=r" (high), "=r" (low), "=r" (high2)
				  : "0" (high), "2" (high2)
				  );
	return ((uint64)high << 32) | low;
}
# define RDTSC_AVAILABLE
#endif

/* In all other cases we have no support for rdtsc. No major issue,
 * you just won't be able to profile your code with TIC()/TOC() */
#if !defined(RDTSC_AVAILABLE)
#warning "(non-fatal) No support for rdtsc(), you won't be able to profile with TIC/TOC"
uint64 _rdtsc(void) {return 0;}
#endif