1 /* Copyright (C) 2001-2013 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3 Contributed by Ryan S. Arnold <rsa@us.ibm.com>
4 Sean Curry <spcurry@us.ibm.com>
6 The GNU C Library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Lesser General Public
8 License as published by the Free Software Foundation; either
9 version 2.1 of the License, or (at your option) any later version.
11 The GNU C Library is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
16 You should have received a copy of the GNU Lesser General Public
17 License along with the GNU C Library; if not, see
18 <http://www.gnu.org/licenses/>. */
30 #include <fpu_control.h>
32 static ucontext_t ctx
[3];
38 static int back_in_main
;
41 volatile static ElfW(auxv_t
) *auxv
= NULL
;
43 ElfW(Addr
) query_auxv(int type
)
46 ElfW(auxv_t
) auxv_struct
;
47 ElfW(auxv_t
) *auxv_temp
;
50 /* if the /proc/self/auxv file has not been manually copied into the heap
55 auxv_f
= fopen("/proc/self/auxv", "r");
59 perror("Error opening file for reading");
62 auxv
= (ElfW(auxv_t
) *)malloc(getpagesize());
66 fread(&auxv_struct
, sizeof(ElfW(auxv_t
)), 1, auxv_f
);
67 auxv
[i
] = auxv_struct
;
69 } while(auxv_struct
.a_type
!= AT_NULL
);
72 auxv_temp
= (ElfW(auxv_t
) *)auxv
;
76 if(auxv_temp
[i
].a_type
== type
)
78 return auxv_temp
[i
].a_un
.a_val
;
81 } while (auxv_temp
[i
].a_type
!= AT_NULL
);
86 typedef unsigned long long di_fpscr_t
__attribute__ ((__mode__ (__DI__
)));
87 typedef unsigned int si_fpscr_t
__attribute__ ((__mode__ (__SI__
)));
89 #define _FPSCR_RESERVED 0xfffffff8ffffff04ULL
91 #define _FPSCR_TEST0_DRN 0x0000000400000000ULL
92 #define _FPSCR_TEST0_RN 0x0000000000000003ULL
94 #define _FPSCR_TEST1_DRN 0x0000000300000000ULL
95 #define _FPSCR_TEST1_RN 0x0000000000000002ULL
97 /* Macros for accessing the hardware control word on Power6[x]. */
98 # define _GET_DI_FPSCR(__fpscr) ({ \
100 di_fpscr_t fpscr; } \
101 tmp __attribute__ ((__aligned__(8))); \
102 __asm__ ("mffs 0; stfd%U0 0,%0" : "=m" (tmp.d) : : "fr0"); \
103 (__fpscr)=tmp.fpscr; \
106 /* We make sure to zero fp0 after we use it in order to prevent stale data
107 in an fp register from making a test-case pass erroneously. */
108 # define _SET_DI_FPSCR(__fpscr) { \
109 union { double d; di_fpscr_t fpscr; } \
110 tmp __attribute__ ((__aligned__(8))); \
111 tmp.fpscr = __fpscr; \
112 /* Set the entire 64-bit FPSCR. */ \
113 __asm__ ("lfd%U0 0,%0; " \
115 ".machine \"power6\"; " \
116 "mtfsf 255,0,1,0; " \
117 ".machine pop" : : "m" (tmp.d) : "fr0"); \
119 __asm__("lfd%U0 0,%0" : : "m" (tmp.d) : "fr0"); \
122 # define _GET_SI_FPSCR(__fpscr) ({ \
124 si_fpscr_t cw[2]; } \
125 tmp __attribute__ ((__aligned__(8))); \
126 __asm__ ("mffs 0; stfd%U0 0,%0" : "=m" (tmp.d) : : "fr0"); \
127 (__fpscr)=tmp.cw[1]; \
130 /* We make sure to zero fp0 after we use it in order to prevent stale data
131 in an fp register from making a test-case pass erroneously. */
132 # define _SET_SI_FPSCR(__fpscr) { \
133 union { double d; si_fpscr_t fpscr[2]; } \
134 tmp __attribute__ ((__aligned__(8))); \
135 /* More-or-less arbitrary; this is a QNaN. */ \
136 tmp.fpscr[0] = 0xFFF80000; \
137 tmp.fpscr[1] = __fpscr; \
138 __asm__ ("lfd%U0 0,%0; mtfsf 255,0" : : "m" (tmp.d) : "fr0"); \
140 __asm__("lfd%U0 0,%0" : : "m" (tmp.d) : "fr0"); \
143 void prime_special_regs(int which
)
147 di_fpscr_t di_fpscr
__attribute__ ((__aligned__(8)));
149 a_val
= query_auxv(AT_HWCAP
);
152 puts ("querying the auxv for the hwcap failed");
156 /* Indicates a 64-bit FPSCR. */
157 if (a_val
& PPC_FEATURE_HAS_DFP
)
159 _GET_DI_FPSCR(di_fpscr
);
161 /* Overwrite the existing DRN and RN if there is one. */
163 di_fpscr
= ((di_fpscr
& _FPSCR_RESERVED
) | (_FPSCR_TEST0_DRN
| _FPSCR_TEST0_RN
));
165 di_fpscr
= ((di_fpscr
& _FPSCR_RESERVED
) | (_FPSCR_TEST1_DRN
| _FPSCR_TEST1_RN
));
166 puts ("Priming 64-bit FPSCR with:");
167 printf("0x%.16llx\n",(unsigned long long int)di_fpscr
);
169 _SET_DI_FPSCR(di_fpscr
);
173 puts ("32-bit FPSCR found and will be tested.");
174 _GET_SI_FPSCR(di_fpscr
);
176 /* Overwrite the existing RN if there is one. */
178 di_fpscr
= ((di_fpscr
& _FPSCR_RESERVED
) | (_FPSCR_TEST0_RN
));
180 di_fpscr
= ((di_fpscr
& _FPSCR_RESERVED
) | (_FPSCR_TEST1_RN
));
181 puts ("Priming 32-bit FPSCR with:");
182 printf("0x%.8lx\n",(unsigned long int) di_fpscr
);
184 _SET_SI_FPSCR(di_fpscr
);
188 void clear_special_regs(void)
192 di_fpscr_t di_fpscr
__attribute__ ((__aligned__(8)));
196 unsigned long long int lli
;
200 a_val
= query_auxv(AT_HWCAP
);
203 puts ("querying the auxv for the hwcap failed");
208 dlli
.d
= ctx
[0].uc_mcontext
.uc_regs
->fpregs
.fpscr
;
210 dlli
.d
= ctx
[0].uc_mcontext
.fp_regs
[32];
213 puts("The FPSCR value saved in the ucontext_t is:");
215 /* Indicates a 64-bit FPSCR. */
216 if (a_val
& PPC_FEATURE_HAS_DFP
)
218 printf("0x%.16llx\n",dlli
.lli
);
220 puts ("Clearing the 64-bit FPSCR to:");
221 printf("0x%.16llx\n",(unsigned long long int) di_fpscr
);
223 _SET_DI_FPSCR(di_fpscr
);
227 printf("0x%.8x\n",(unsigned int) dlli
.li
[1]);
229 puts ("Clearing the 32-bit FPSCR to:");
230 printf("0x%.8lx\n",(unsigned long int) di_fpscr
);
232 _SET_SI_FPSCR(di_fpscr
);
236 void test_special_regs(int which
)
239 unsigned long long int test
;
241 di_fpscr_t di_fpscr
__attribute__ ((__aligned__(8)));
243 a_val
= query_auxv(AT_HWCAP
);
246 puts ("querying the auxv for the hwcap failed");
250 /* Indicates a 64-bit FPSCR. */
251 if (a_val
& PPC_FEATURE_HAS_DFP
)
253 _GET_DI_FPSCR(di_fpscr
);
256 puts ("After setcontext the 64-bit FPSCR contains:");
258 puts ("After swapcontext the 64-bit FPSCR contains:");
260 printf("0x%.16llx\n",(unsigned long long int) di_fpscr
);
261 test
= (_FPSCR_TEST0_DRN
| _FPSCR_TEST0_RN
);
262 if((di_fpscr
& (test
)) != (test
))
264 printf ("%s: DRN and RN bits set before getcontext were not preserved across [set|swap]context call: %m",__FUNCTION__
);
270 _GET_SI_FPSCR(di_fpscr
);
272 puts ("After setcontext the 32-bit FPSCR contains:");
274 puts ("After swapcontext the 32-bit FPSCR contains:");
276 printf("0x%.8lx\n",(unsigned long int) di_fpscr
);
277 test
= _FPSCR_TEST0_RN
;
278 if((di_fpscr
& test
) != test
)
280 printf ("%s: RN bit set before getcontext was not preserved across [set|swap]context call: %m",__FUNCTION__
);
290 if (back_in_main
== 0)
292 puts ("program did not reach main again");
301 atexit (check_called
);
303 puts ("priming the FPSCR with a marker");
304 prime_special_regs (0);
306 puts ("making contexts");
307 if (getcontext (&ctx
[0]) != 0)
315 printf ("%s: getcontext: %m\n", __FUNCTION__
);
319 /* Play some tricks with this context. */
322 clear_special_regs ( );
323 if (setcontext (&ctx
[0]) != 0)
325 printf ("%s: setcontext: %m\n", __FUNCTION__
);
331 printf ("%s: 'global' not incremented twice\n", __FUNCTION__
);
335 test_special_regs (0);
338 if (getcontext (&ctx
[0]) != 0)
340 printf ("%s: getcontext: %m\n", __FUNCTION__
);
346 puts ("priming the FPSCR with a marker");
347 prime_special_regs (1);
349 puts ("swapping contexts");
350 if (swapcontext (&ctx
[1], &ctx
[0]) != 0)
352 printf ("%s: swapcontext: %m\n", __FUNCTION__
);
358 printf ("%s: 'global' not incremented twice\n", __FUNCTION__
);
362 test_special_regs (1);
364 puts ("back at main program");
367 puts ("test succeeded");