diff options
Diffstat (limited to 'sysdeps/aarch64/tst-vpcs.c')
| -rw-r--r-- | sysdeps/aarch64/tst-vpcs.c | 78 |
1 files changed, 78 insertions, 0 deletions
diff --git a/sysdeps/aarch64/tst-vpcs.c b/sysdeps/aarch64/tst-vpcs.c new file mode 100644 index 0000000000..92a701eb7c --- /dev/null +++ b/sysdeps/aarch64/tst-vpcs.c @@ -0,0 +1,78 @@ +/* Test that variant PCS calls don't clobber registers with lazy binding. + Copyright (C) 2020 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + 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 + <https://www.gnu.org/licenses/>. */ + +#include <stdint.h> +#include <stdio.h> +#include <support/check.h> + +struct regs +{ + uint64_t x[32]; + union { + long double q[32]; + uint64_t u[64]; + } v; +}; + +/* Gives the registers in the caller and callee around a variant PCS call. + Most registers are initialized from BEFORE in the caller so they can + have values that likely show clobbers. Register state extensions such + as SVE is not covered here, only the base registers. */ +void vpcs_call_regs (struct regs *after, struct regs *before); + +static int +do_test (void) +{ + struct regs before, after; + int err = 0; + + unsigned char *p = (unsigned char *)&before; + for (int i = 0; i < sizeof before; i++) + p[i] = i & 0xff; + + vpcs_call_regs (&after, &before); + + for (int i = 0; i < 32; i++) + if (before.x[i] != after.x[i]) + { + if (i == 16 || i == 17) + /* Variant PCS allows clobbering x16 and x17. */ + continue; + err++; + printf ("x%d: before: 0x%016llx after: 0x%016llx\n", + i, + (unsigned long long)before.x[i], + (unsigned long long)after.x[i]); + } + for (int i = 0; i < 64; i++) + if (before.v.u[i] != after.v.u[i]) + { + err++; + printf ("v%d: before: 0x%016llx %016llx after: 0x%016llx %016llx\n", + i/2, + (unsigned long long)before.v.u[2*(i/2)+1], + (unsigned long long)before.v.u[2*(i/2)], + (unsigned long long)after.v.u[2*(i/2)+1], + (unsigned long long)after.v.u[2*(i/2)]); + } + if (err) + FAIL_EXIT1 ("The variant PCS call clobbered %d registers.\n", err); + return 0; +} + +#include <support/test-driver.c> |