libcilkrts/runtime/config/x86/os-unix-sysdep.c

   1 /* os-unix-sysdep.c                  -*-C-*-
   2  *
   3  *************************************************************************
   4  *
   5  *  @copyright
   6  *  Copyright (C) 2009-2013, Intel Corporation
   7  *  All rights reserved.
   8  *
   9  *  @copyright
  10  *  Redistribution and use in source and binary forms, with or without
  11  *  modification, are permitted provided that the following conditions
  12  *  are met:
  13  *
  14  *    * Redistributions of source code must retain the above copyright
  15  *      notice, this list of conditions and the following disclaimer.
  16  *    * Redistributions in binary form must reproduce the above copyright
  17  *      notice, this list of conditions and the following disclaimer in
  18  *      the documentation and/or other materials provided with the
  19  *      distribution.
  20  *    * Neither the name of Intel Corporation nor the names of its
  21  *      contributors may be used to endorse or promote products derived
  22  *      from this software without specific prior written permission.
  23  *
  24  *  @copyright
  25  *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  26  *  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  27  *  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  28  *  A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  29  *  HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  30  *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
  31  *  BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
  32  *  OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  33  *  AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  34  *  LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY
  35  *  WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  36  *  POSSIBILITY OF SUCH DAMAGE.
  37  *************************************************************************
  38  *
  39  * This file contains system-specific code for Unix systems
  40  */
  41
  42 #include "os.h"
  43 #include "sysdep.h"
  44 #include <internal/abi.h>
  45
  46 // On x86 processors (but not MIC processors), the compiler generated code to
  47 // save the FP state (rounding mode and the like) before calling setjmp.  We
  48 // will need to restore that state when we resume.
  49 #ifndef __MIC__
  50 # if defined(__i386__) || defined(__x86_64)
  51 #   define RESTORE_X86_FP_STATE
  52 # endif // defined(__i386__) || defined(__x86_64)
  53 #endif  // __MIC__
  54
  55 /* timer support */
  56 COMMON_SYSDEP unsigned long long __cilkrts_getticks(void)
  57 {
  58 #if defined __i386__ || defined __x86_64
  59     unsigned a, d;
  60     __asm__ volatile("rdtsc" : "=a" (a), "=d" (d));
  61     return ((unsigned long long)a) | (((unsigned long long)d) << 32);
  62 #else
  63 #   warning "unimplemented cycle counter"
  64     return 0;
  65 #endif
  66 }
  67
  68 COMMON_SYSDEP void __cilkrts_short_pause(void)
  69 {
  70 #if __ICC >= 1110
  71 #   if __MIC__ || __MIC2__
  72     _mm_delay_32(16); // stall for 16 cycles
  73 #   else
  74     _mm_pause();
  75 #   endif
  76 #elif defined __i386__ || defined __x86_64
  77     __asm__("pause");
  78 #else
  79 #   warning __cilkrts_short_pause empty
  80 #endif
  81 }
  82
  83 COMMON_SYSDEP int __cilkrts_xchg(volatile int *ptr, int x)
  84 {
  85 #if defined __i386__ || defined __x86_64
  86     /* asm statement here works around icc bugs */
  87     __asm__("xchgl %0,%a1" :"=r" (x) : "r" (ptr), "0" (x) :"memory");
  88 #else
  89     x = __sync_lock_test_and_set(ptr, x);
  90 #endif
  91     return x;
  92 }
  93
  94
  95 /*
  96  * Restore the floating point state that is stored in a stack frame at each
  97  * spawn.  This should be called each time a frame is resumed.
  98  *
  99  * Only valid for IA32 and Intel64 processors.
 100  */
 101 void restore_x86_fp_state (__cilkrts_stack_frame *sf) {
 102 #ifdef RESTORE_X86_FP_STATE
 103     __asm__ ( "ldmxcsr %0\n\t"
 104               "fnclex\n\t"
 105               "fldcw %1"
 106               :
 107               : "m" (sf->mxcsr), "m" (sf->fpcsr));
 108 #endif
 109 }
 110
 111
 112 void sysdep_save_fp_ctrl_state(__cilkrts_stack_frame *sf)
 113 {
 114 // If we're not going to restore, don't bother saving it
 115 #ifdef RESTORE_X86_FP_STATE
 116     if (CILK_FRAME_VERSION_VALUE(sf->flags) >= 1)
 117     {
 118         __asm__ ("stmxcsr %0" : "=m" (sf->mxcsr));
 119         __asm__ ("fnstsw %0" : "=m" (sf->fpcsr));
 120     }
 121 #endif
 122 }
 123