diff options
Diffstat (limited to 'REORG.TODO/sysdeps/powerpc/fpu/tst-setcontext-fpscr.c')
-rw-r--r-- | REORG.TODO/sysdeps/powerpc/fpu/tst-setcontext-fpscr.c | 370 |
1 files changed, 370 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/powerpc/fpu/tst-setcontext-fpscr.c b/REORG.TODO/sysdeps/powerpc/fpu/tst-setcontext-fpscr.c new file mode 100644 index 0000000000..4e3f90d4d3 --- /dev/null +++ b/REORG.TODO/sysdeps/powerpc/fpu/tst-setcontext-fpscr.c @@ -0,0 +1,370 @@ +/* Copyright (C) 2001-2017 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Ryan S. Arnold <rsa@us.ibm.com> + Sean Curry <spcurry@us.ibm.com> + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + <http://www.gnu.org/licenses/>. */ + +#include <errno.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <ucontext.h> +#include <unistd.h> +#include <malloc.h> +#include <link.h> +#include <elf.h> +#include <fpu_control.h> +#include <sys/auxv.h> + +static ucontext_t ctx[3]; + + +volatile int global; + + +static int back_in_main; + + +volatile static ElfW(auxv_t) *auxv = NULL; + +ElfW(Addr) query_auxv(int type) +{ + FILE *auxv_f; + ElfW(auxv_t) auxv_struct; + ElfW(auxv_t) *auxv_temp; + int i = 0; + + /* if the /proc/self/auxv file has not been manually copied into the heap + yet, then do it */ + + if(auxv == NULL) + { + auxv_f = fopen("/proc/self/auxv", "r"); + + if(auxv_f == 0) + { + perror("Error opening file for reading"); + return 0; + } + auxv = (ElfW(auxv_t) *)malloc(getpagesize()); + + do + { + fread(&auxv_struct, sizeof(ElfW(auxv_t)), 1, auxv_f); + auxv[i] = auxv_struct; + i++; + } while(auxv_struct.a_type != AT_NULL); + } + + auxv_temp = (ElfW(auxv_t) *)auxv; + i = 0; + do + { + if(auxv_temp[i].a_type == type) + { + return auxv_temp[i].a_un.a_val; + } + i++; + } while (auxv_temp[i].a_type != AT_NULL); + + return 0; +} + +typedef unsigned int di_fpscr_t __attribute__ ((__mode__ (__DI__))); +typedef unsigned int si_fpscr_t __attribute__ ((__mode__ (__SI__))); + +#define _FPSCR_RESERVED 0xfffffff8ffffff04ULL + +#define _FPSCR_TEST0_DRN 0x0000000400000000ULL +#define _FPSCR_TEST0_RN 0x0000000000000003ULL + +#define _FPSCR_TEST1_DRN 0x0000000300000000ULL +#define _FPSCR_TEST1_RN 0x0000000000000002ULL + +/* Macros for accessing the hardware control word on Power6[x]. */ +#define _GET_DI_FPSCR(__fpscr) \ + ({union { double d; di_fpscr_t fpscr; } u; \ + register double fr; \ + __asm__ ("mffs %0" : "=f" (fr)); \ + u.d = fr; \ + (__fpscr) = u.fpscr; \ + u.fpscr; \ + }) + +/* We make sure to zero fp after we use it in order to prevent stale data + in an fp register from making a test-case pass erroneously. */ +# define _SET_DI_FPSCR(__fpscr) \ + { union { double d; di_fpscr_t fpscr; } u; \ + register double fr; \ + u.fpscr = __fpscr; \ + fr = u.d; \ + /* Set the entire 64-bit FPSCR. */ \ + __asm__ (".machine push; " \ + ".machine \"power6\"; " \ + "mtfsf 255,%0,1,0; " \ + ".machine pop" : : "f" (fr)); \ + fr = 0.0; \ + } + +# define _GET_SI_FPSCR(__fpscr) \ + ({union { double d; di_fpscr_t fpscr; } u; \ + register double fr; \ + __asm__ ("mffs %0" : "=f" (fr)); \ + u.d = fr; \ + (__fpscr) = (si_fpscr_t) u.fpscr; \ + (si_fpscr_t) u.fpscr; \ + }) + +/* We make sure to zero fp after we use it in order to prevent stale data + in an fp register from making a test-case pass erroneously. */ +# define _SET_SI_FPSCR(__fpscr) \ + { union { double d; di_fpscr_t fpscr; } u; \ + register double fr; \ + /* More-or-less arbitrary; this is a QNaN. */ \ + u.fpscr = 0xfff80000ULL << 32; \ + u.fpscr |= __fpscr & 0xffffffffULL; \ + fr = u.d; \ + __asm__ ("mtfsf 255,%0" : : "f" (fr)); \ + fr = 0.0; \ + } + +void prime_special_regs(int which) +{ + ElfW(Addr) a_val; + + di_fpscr_t di_fpscr __attribute__ ((__aligned__(8))); + + a_val = query_auxv(AT_HWCAP); + if(a_val == -1) + { + puts ("querying the auxv for the hwcap failed"); + _exit (1); + } + + /* Indicates a 64-bit FPSCR. */ + if (a_val & PPC_FEATURE_HAS_DFP) + { + _GET_DI_FPSCR(di_fpscr); + + /* Overwrite the existing DRN and RN if there is one. */ + if (which == 0) + di_fpscr = ((di_fpscr & _FPSCR_RESERVED) | (_FPSCR_TEST0_DRN | _FPSCR_TEST0_RN)); + else + di_fpscr = ((di_fpscr & _FPSCR_RESERVED) | (_FPSCR_TEST1_DRN | _FPSCR_TEST1_RN)); + puts ("Priming 64-bit FPSCR with:"); + printf("0x%.16llx\n",(unsigned long long int)di_fpscr); + + _SET_DI_FPSCR(di_fpscr); + } + else + { + puts ("32-bit FPSCR found and will be tested."); + _GET_SI_FPSCR(di_fpscr); + + /* Overwrite the existing RN if there is one. */ + if (which == 0) + di_fpscr = ((di_fpscr & _FPSCR_RESERVED) | (_FPSCR_TEST0_RN)); + else + di_fpscr = ((di_fpscr & _FPSCR_RESERVED) | (_FPSCR_TEST1_RN)); + puts ("Priming 32-bit FPSCR with:"); + printf("0x%.8lx\n",(unsigned long int) di_fpscr); + + _SET_SI_FPSCR(di_fpscr); + } +} + +void clear_special_regs(void) +{ + ElfW(Addr) a_val; + + di_fpscr_t di_fpscr __attribute__ ((__aligned__(8))); + + union { + double d; + unsigned long long int lli; + unsigned int li[2]; + } dlli; + + a_val = query_auxv(AT_HWCAP); + if(a_val == -1) + { + puts ("querying the auxv for the hwcap failed"); + _exit (1); + } + +#if __WORDSIZE == 32 + dlli.d = ctx[0].uc_mcontext.uc_regs->fpregs.fpscr; +#else + dlli.d = ctx[0].uc_mcontext.fp_regs[32]; +#endif + + puts("The FPSCR value saved in the ucontext_t is:"); + + /* Indicates a 64-bit FPSCR. */ + if (a_val & PPC_FEATURE_HAS_DFP) + { + printf("0x%.16llx\n",dlli.lli); + di_fpscr = 0x0; + puts ("Clearing the 64-bit FPSCR to:"); + printf("0x%.16llx\n",(unsigned long long int) di_fpscr); + + _SET_DI_FPSCR(di_fpscr); + } + else + { + printf("0x%.8x\n",(unsigned int) dlli.li[1]); + di_fpscr = 0x0; + puts ("Clearing the 32-bit FPSCR to:"); + printf("0x%.8lx\n",(unsigned long int) di_fpscr); + + _SET_SI_FPSCR(di_fpscr); + } +} + +void test_special_regs(int which) +{ + ElfW(Addr) a_val; + unsigned long long int test; + + di_fpscr_t di_fpscr __attribute__ ((__aligned__(8))); + + a_val = query_auxv(AT_HWCAP); + if(a_val == -1) + { + puts ("querying the auxv for the hwcap failed"); + _exit (2); + } + + /* Indicates a 64-bit FPSCR. */ + if (a_val & PPC_FEATURE_HAS_DFP) + { + _GET_DI_FPSCR(di_fpscr); + + if (which == 0) + puts ("After setcontext the 64-bit FPSCR contains:"); + else + puts ("After swapcontext the 64-bit FPSCR contains:"); + + printf("0x%.16llx\n",(unsigned long long int) di_fpscr); + test = (_FPSCR_TEST0_DRN | _FPSCR_TEST0_RN); + if((di_fpscr & (test)) != (test)) + { + printf ("%s: DRN and RN bits set before getcontext were not preserved across [set|swap]context call: %m",__FUNCTION__); + _exit (3); + } + } + else + { + _GET_SI_FPSCR(di_fpscr); + if (which == 0) + puts ("After setcontext the 32-bit FPSCR contains:"); + else + puts ("After swapcontext the 32-bit FPSCR contains:"); + + printf("0x%.8lx\n",(unsigned long int) di_fpscr); + test = _FPSCR_TEST0_RN; + if((di_fpscr & test) != test) + { + printf ("%s: RN bit set before getcontext was not preserved across [set|swap]context call: %m",__FUNCTION__); + _exit (4); + } + } +} + + +static void +check_called (void) +{ + if (back_in_main == 0) + { + puts ("program did not reach main again"); + _exit (5); + } +} + + +int +main (void) +{ + atexit (check_called); + + puts ("priming the FPSCR with a marker"); + prime_special_regs (0); + + puts ("making contexts"); + if (getcontext (&ctx[0]) != 0) + { + if (errno == ENOSYS) + { + back_in_main = 1; + exit (0); + } + + printf ("%s: getcontext: %m\n", __FUNCTION__); + exit (6); + } + + /* Play some tricks with this context. */ + if (++global == 1) + { + clear_special_regs ( ); + if (setcontext (&ctx[0]) != 0) + { + printf ("%s: setcontext: %m\n", __FUNCTION__); + exit (7); + } + } + if (global != 2) + { + printf ("%s: 'global' not incremented twice\n", __FUNCTION__); + exit (8); + } + + test_special_regs (0); + + global = 0; + if (getcontext (&ctx[0]) != 0) + { + printf ("%s: getcontext: %m\n", __FUNCTION__); + exit (9); + } + + if (++global == 1) + { + puts ("priming the FPSCR with a marker"); + prime_special_regs (1); + + puts ("swapping contexts"); + if (swapcontext (&ctx[1], &ctx[0]) != 0) + { + printf ("%s: swapcontext: %m\n", __FUNCTION__); + exit (9); + } + } + if (global != 2) + { + printf ("%s: 'global' not incremented twice\n", __FUNCTION__); + exit (10); + } + + test_special_regs (1); + + puts ("back at main program"); + back_in_main = 1; + + puts ("test succeeded"); + return 0; +} |