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Diffstat (limited to 'sysdeps/unix/sysv/linux/s390/htm.h')
| -rw-r--r-- | sysdeps/unix/sysv/linux/s390/htm.h | 187 |
1 files changed, 187 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/s390/htm.h b/sysdeps/unix/sysv/linux/s390/htm.h new file mode 100644 index 0000000000..b97f15f0c5 --- /dev/null +++ b/sysdeps/unix/sysv/linux/s390/htm.h @@ -0,0 +1,187 @@ +/* Shared HTM header. Work around false transactional execution facility + intrinsics. + + Copyright (C) 2016-2018 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 + <http://www.gnu.org/licenses/>. */ + +#ifndef _HTM_H +#define _HTM_H 1 + +#include <htmintrin.h> + +#ifdef __s390x__ +# define TX_FPRS_BYTES 64 +# define TX_SAVE_FPRS \ + " std %%f8, 0(%[R_FPRS])\n\t" \ + " std %%f9, 8(%[R_FPRS])\n\t" \ + " std %%f10, 16(%[R_FPRS])\n\t" \ + " std %%f11, 24(%[R_FPRS])\n\t" \ + " std %%f12, 32(%[R_FPRS])\n\t" \ + " std %%f13, 40(%[R_FPRS])\n\t" \ + " std %%f14, 48(%[R_FPRS])\n\t" \ + " std %%f15, 56(%[R_FPRS])\n\t" + +# define TX_RESTORE_FPRS \ + " ld %%f8, 0(%[R_FPRS])\n\t" \ + " ld %%f9, 8(%[R_FPRS])\n\t" \ + " ld %%f10, 16(%[R_FPRS])\n\t" \ + " ld %%f11, 24(%[R_FPRS])\n\t" \ + " ld %%f12, 32(%[R_FPRS])\n\t" \ + " ld %%f13, 40(%[R_FPRS])\n\t" \ + " ld %%f14, 48(%[R_FPRS])\n\t" \ + " ld %%f15, 56(%[R_FPRS])\n\t" + +#else + +# define TX_FPRS_BYTES 16 +# define TX_SAVE_FPRS \ + " std %%f4, 0(%[R_FPRS])\n\t" \ + " std %%f6, 8(%[R_FPRS])\n\t" + +# define TX_RESTORE_FPRS \ + " ld %%f4, 0(%[R_FPRS])\n\t" \ + " ld %%f6, 8(%[R_FPRS])\n\t" + +#endif /* ! __s390x__ */ + +/* Use own inline assembly instead of __builtin_tbegin, as tbegin + has to filter program interruptions which can't be done with the builtin. + Now the fprs have to be saved / restored here, too. + The fpc is also not saved / restored with the builtin. + The used inline assembly does not clobber the volatile fprs / vrs! + Clobbering the latter ones would force the compiler to save / restore + the call saved fprs as those overlap with the vrs, but they only need to be + restored if the transaction fails but not if the transaction is successfully + started. Thus the user of the tbegin macros in this header file has to + compile the file / function with -msoft-float. It prevents gcc from using + fprs / vrs. */ +#define __libc_tbegin(tdb) __libc_tbegin_base(tdb,,,) + +#define __libc_tbegin_retry_output_regs , [R_TX_CNT] "+&d" (__tx_cnt) +#define __libc_tbegin_retry_input_regs(retry_cnt) , [R_RETRY] "d" (retry_cnt) +#define __libc_tbegin_retry_abort_path_insn \ + /* If tbegin returned _HTM_TBEGIN_TRANSIENT, retry immediately so \ + that max tbegin_cnt transactions are tried. Otherwise return and \ + let the caller of this macro do the fallback path. */ \ + " jnh 1f\n\t" /* cc 1/3: jump to fallback path. */ \ + /* tbegin returned _HTM_TBEGIN_TRANSIENT: retry with transaction. */ \ + " crje %[R_TX_CNT], %[R_RETRY], 1f\n\t" /* Reached max retries? */ \ + " ahi %[R_TX_CNT], 1\n\t" \ + " ppa %[R_TX_CNT], 0, 1\n\t" /* Transaction-Abort Assist. */ \ + " j 2b\n\t" /* Loop to tbegin. */ + +/* Same as __libc_tbegin except if tbegin aborts with _HTM_TBEGIN_TRANSIENT. + Then this macros restores the fpc, fprs and automatically retries up to + retry_cnt tbegins. Further saving of the state is omitted as it is already + saved. This macro calls tbegin at most as retry_cnt + 1 times. */ +#define __libc_tbegin_retry(tdb, retry_cnt) \ + ({ int __ret; \ + int __tx_cnt = 0; \ + __ret = __libc_tbegin_base(tdb, \ + __libc_tbegin_retry_abort_path_insn, \ + __libc_tbegin_retry_output_regs, \ + __libc_tbegin_retry_input_regs(retry_cnt)); \ + __ret; \ + }) + +#define __libc_tbegin_base(tdb, abort_path_insn, output_regs, input_regs) \ + ({ int __ret; \ + int __fpc; \ + char __fprs[TX_FPRS_BYTES]; \ + __asm__ __volatile__ (".machine push\n\t" \ + ".machinemode \"zarch_nohighgprs\"\n\t" \ + ".machine \"all\"\n\t" \ + /* Save state at the outermost transaction. \ + As extracting nesting depth is expensive \ + on at least zEC12, save fprs at inner \ + transactions, too. \ + The fpc and fprs are saved here as they \ + are not saved by tbegin. There exist no \ + call-saved vrs, thus they are not saved \ + here. */ \ + " efpc %[R_FPC]\n\t" \ + TX_SAVE_FPRS \ + /* Begin transaction: save all gprs, allow \ + ar modification and fp operations. Some \ + program-interruptions (e.g. a null \ + pointer access) are filtered and the \ + transaction will abort. In this case \ + the normal lock path will execute it \ + again and result in a core dump wich does \ + now show at tbegin but the real executed \ + instruction. \ + However it is not guaranteed that this \ + retry operate on the same data and thus \ + may not end in an program-interruption. \ + Note: This could also be used to probe \ + memory for being accessible! */ \ + "2: tbegin 0, 0xFF0E\n\t" \ + /* Branch away in abort case (this is the \ + prefered sequence. See PoP in chapter 5 \ + Transactional-Execution Facility \ + Operation). */ \ + " jnz 0f\n\t" \ + /* Transaction has successfully started. */ \ + " lhi %[R_RET], 0\n\t" \ + " j 1f\n\t" \ + /* Transaction has aborted. Now we are at \ + the outermost transaction. Restore fprs \ + and fpc. */ \ + "0: ipm %[R_RET]\n\t" \ + " srl %[R_RET], 28\n\t" \ + " sfpc %[R_FPC]\n\t" \ + TX_RESTORE_FPRS \ + abort_path_insn \ + "1:\n\t" \ + ".machine pop\n" \ + : [R_RET] "=&d" (__ret), \ + [R_FPC] "=&d" (__fpc) \ + output_regs \ + : [R_FPRS] "a" (__fprs) \ + input_regs \ + : "cc", "memory"); \ + __ret; \ + }) + +/* These builtins are usable in context of glibc lock elision code without any + changes. Use them. */ +#define __libc_tend() \ + ({ __asm__ __volatile__ (".machine push\n\t" \ + ".machinemode \"zarch_nohighgprs\"\n\t" \ + ".machine \"all\"\n\t"); \ + int __ret = __builtin_tend (); \ + __asm__ __volatile__ (".machine pop"); \ + __ret; \ + }) + +#define __libc_tabort(abortcode) \ + __asm__ __volatile__ (".machine push\n\t" \ + ".machinemode \"zarch_nohighgprs\"\n\t" \ + ".machine \"all\"\n\t"); \ + __builtin_tabort (abortcode); \ + __asm__ __volatile__ (".machine pop") + +#define __libc_tx_nesting_depth() \ + ({ __asm__ __volatile__ (".machine push\n\t" \ + ".machinemode \"zarch_nohighgprs\"\n\t" \ + ".machine \"all\"\n\t"); \ + int __ret = __builtin_tx_nesting_depth (); \ + __asm__ __volatile__ (".machine pop"); \ + __ret; \ + }) + +#endif |