1

/* $Id$ */

     2

     3

#include "stdafx.h"

     4

     5

#undef RDTSC_AVAILABLE

     6

     7

/* rdtsc for MSC_VER, uses simple inline assembly, or _rdtsc

     8

 * from external win64.asm because VS2005 does not support inline assembly */

     9

#if defined(_MSC_VER) && !defined(RDTSC_AVAILABLE)

    10

# if defined (_M_AMD64)

    11

extern uint64 _rdtsc(void);

    12

#	else

    13

uint64 _declspec(naked) _rdtsc(void)

    14

{

    15

	_asm {

    16

		rdtsc

    17

		ret

    18

	}

    19

}

    20

# endif

    21

# define RDTSC_AVAILABLE

    22

#endif

    23

    24

/* rdtsc for OS/2. Hopefully this works, who knows */

    25

#if defined (__WATCOMC__) && !defined(RDTSC_AVAILABLE)

    26

unsigned __int64 _rdtsc( void);

    27

# pragma aux _rdtsc = 0x0F 0x31 value [edx eax] parm nomemory modify exact [edx eax] nomemory;

    28

# define RDTSC_AVAILABLE

    29

#endif

    30

    31

/* rdtsc for all other *nix-en (hopefully). Use GCC syntax */

    32

#if defined(__i386__) || defined(__x86_64__) && !defined(RDTSC_AVAILABLE)

    33

uint64 _rdtsc(void)

    34

{

    35

	uint32 high, low;

    36

	__asm__ __volatile__ ("rdtsc" : "=a" (low), "=d" (high));

    37

	return ((uint64)high << 32) | low;

    38

}

    39

# define RDTSC_AVAILABLE

    40

#endif

    41

    42

/* rdtsc for PPC which has this not */

    43

#if (defined(__POWERPC__) || defined(__powerpc__)) && !defined(RDTSC_AVAILABLE)

    44

uint64 _rdtsc(void)

    45

{

    46

	uint32 high = 0, high2 = 0, low;

    47

	/* PPC does not have rdtsc, so we cheat by reading the two 32-bit time-counters

    48

	 * it has, 'Move From Time Base (Upper)'. Since these are two reads, in the

    49

	 * very unlikely event that the lower part overflows to the upper part while we

    50

	 * read it; we double-check and reread the registers */

    51

	asm volatile (

    52

				  "mftbu %0\n"

    53

				  "mftb %1\n"

    54

				  "mftbu %2\n"

    55

				  "cmpw %3,%4\n"

    56

				  "bne- $-16\n"

    57

				  : "=r" (high), "=r" (low), "=r" (high2)

    58

				  : "0" (high), "2" (high2)

    59

				  );

    60

	return ((uint64)high << 32) | low;

    61

}

    62

# define RDTSC_AVAILABLE

    63

#endif

    64

    65

/* In all other cases we have no support for rdtsc. No major issue,

    66

 * you just won't be able to profile your code with TIC()/TOC() */

    67

#if !defined(RDTSC_AVAILABLE)

    68

#warning "(non-fatal) No support for rdtsc(), you won't be able to profile with TIC/TOC"

    69

uint64 _rdtsc(void) {return 0;}

    70

#endif