| dnl Alpha time stamp counter access routine. |
| |
| dnl Copyright 2000, 2005 Free Software Foundation, Inc. |
| dnl |
| dnl This file is part of the GNU MP Library. |
| dnl |
| dnl The GNU MP Library is free software; you can redistribute it and/or |
| dnl modify it under the terms of the GNU Lesser General Public License as |
| dnl published by the Free Software Foundation; either version 3 of the |
| dnl License, or (at your option) any later version. |
| dnl |
| dnl The GNU MP Library is distributed in the hope that it will be useful, |
| dnl but WITHOUT ANY WARRANTY; without even the implied warranty of |
| dnl MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| dnl Lesser General Public License for more details. |
| dnl |
| dnl You should have received a copy of the GNU Lesser General Public License |
| dnl along with the GNU MP Library. If not, see http://www.gnu.org/licenses/. |
| |
| include(`../config.m4') |
| |
| |
| C void speed_cyclecounter (unsigned int p[2]); |
| C |
| |
| C The rpcc instruction returns a 64-bit value split into two 32-bit fields. |
| C The lower 32 bits are set by the hardware, and the upper 32 bits are set |
| C by the operating system. The real per-process cycle count is the sum of |
| C these halves. |
| |
| C Unfortunately, some operating systems don't get this right. NetBSD 1.3 is |
| C known to sometimes put garbage in the upper half. Whether newer NetBSD |
| C versions get it right, is unknown to us. |
| |
| C rpcc measures cycles elapsed in the user program and hence should be very |
| C accurate even on a busy system. Losing cache contents due to task |
| C switching may have an effect though. |
| |
| ASM_START() |
| PROLOGUE(speed_cyclecounter) |
| rpcc r0 |
| srl r0,32,r1 |
| addq r1,r0,r0 |
| stl r0,0(r16) |
| stl r31,4(r16) C zero upper return word |
| ret r31,(r26),1 |
| EPILOGUE(speed_cyclecounter) |
| ASM_END() |
