| /* 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 |
