cosmopolitan/libc/testlib/thrashcodecache.S
Justine Tunney 8f522cb702
Make improvements
This change progresses our AARCH64 support:

- The AARCH64 build and tests are now passing
- Add 128-bit floating-point support to printf()
- Fix clone() so it initializes cosmo's x28 TLS register
- Fix TLS memory layout issue with aarch64 _Alignas vars
- Revamp microbenchmarking tools so they work on aarch64
- Make some subtle improvements to aarch64 crash reporting
- Make kisdangerous() memory checks more accurate on aarch64
- Remove sys_open() since it's not available on Linux AARCH64

This change makes general improvements to Cosmo and Redbean:

- Introduce GetHostIsa() function in Redbean
- You can now feature check using pledge(0, 0)
- You can now feature check using unveil("",0)
- Refactor some more x86-specific asm comments
- Refactor and write docs for some libm functions
- Make the mmap() API behave more similar to Linux
- Fix WIFSIGNALED() which wrongly returned true for zero
- Rename some obscure cosmo keywords from noFOO to dontFOO
2023-06-03 08:12:22 -07:00

49 lines
2.4 KiB
ArmAsm

/*-*- mode:unix-assembly; indent-tabs-mode:t; tab-width:8; coding:utf-8 -*-│
vi: set et ft=asm ts=8 tw=8 fenc=utf-8 :vi
Copyright 2020 Justine Alexandra Roberts Tunney
Permission to use, copy, modify, and/or distribute this software for
any purpose with or without fee is hereby granted, provided that the
above copyright notice and this permission notice appear in all copies.
THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL
WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE
AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
PERFORMANCE OF THIS SOFTWARE.
*/
#include "libc/macros.internal.h"
.testonly
// Empties L1 instruction cache.
thrashcodecache:
#ifdef __x86_64__
.leafprologue
push %rbx
xor %eax,%eax
xor %ecx,%ecx
cpuid
add %r9,%r8
// Generate 32kb of junk code clobbering r8,r9,r10,r11
i = 0xdeadbeef
0: .rept 32768/(3+7)
rex.wrb
.byte 0001|(i&030) // ADD/OR/... Evqp Gvqp
.byte 0300|(i&033) // %r8-%r11 to %r8-%r11
.byte 0x49,0x81,0360|(i&003) // XOR immed32,%r8-%r11
.long i
i = ((i * 1103515245 + 12345) >> 16) & 0xffffffff
.endr
xor %eax,%eax
xor %ecx,%ecx
cpuid
pop %rbx
.leafepilogue
#else
ret
#endif
.endfn thrashcodecache,globl