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diff --git a/REORG.TODO/sysdeps/unix/sysv/linux/s390/htm.h b/REORG.TODO/sysdeps/unix/sysv/linux/s390/htm.h
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+++ b/REORG.TODO/sysdeps/unix/sysv/linux/s390/htm.h
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+/* Shared HTM header.  Work around false transactional execution facility
+   intrinsics.
+
+   Copyright (C) 2016-2017 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