lib/libc/sparc64/sys/__sparc_utrap_align.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
   3  *
   4  * Copyright (c) 2002 Jake Burkholder.
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  19  * IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
  20  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  21  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  22  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  23  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  24  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
  25  * USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  26  */
  27
  28 #include <sys/cdefs.h>
  29 __FBSDID("$FreeBSD$");
  30
  31 #include <sys/types.h>
  32 #include <machine/cpufunc.h>
  33 #include <machine/instr.h>
  34
  35 #include <signal.h>
  36
  37 #include "__sparc_utrap_private.h"
  38
  39 static u_long
  40 __unaligned_load(u_char *p, int size)
  41 {
  42         u_long val;
  43         int i;
  44
  45         val = 0;
  46         for (i = 0; i < size; i++)
  47                 val = (val << 8) | p[i];
  48         return (val);
  49 }
  50
  51 static void
  52 __unaligned_store(u_char *p, u_long val, int size)
  53 {
  54         int i;
  55
  56         for (i = 0; i < size; i++)
  57                 p[i] = val >> ((size - i - 1) * 8);
  58 }
  59
  60 int
  61 __unaligned_fixup(struct utrapframe *uf)
  62 {
  63         u_char *addr;
  64         u_long val;
  65         u_int insn;
  66         int sig;
  67
  68         sig = 0;
  69         addr = (u_char *)uf->uf_sfar;
  70         insn = *(u_int *)uf->uf_pc;
  71         flushw();
  72         switch (IF_OP(insn)) {
  73         case IOP_LDST:
  74                 switch (IF_F3_OP3(insn)) {
  75                 case INS3_LDUH:
  76                         val = __unaligned_load(addr, 2);
  77                         __emul_store_reg(uf, IF_F3_RD(insn), val);
  78                         break;
  79                 case INS3_LDUW:
  80                         val = __unaligned_load(addr, 4);
  81                         __emul_store_reg(uf, IF_F3_RD(insn), val);
  82                         break;
  83                 case INS3_LDX:
  84                         val = __unaligned_load(addr, 8);
  85                         __emul_store_reg(uf, IF_F3_RD(insn), val);
  86                         break;
  87                 case INS3_LDSH:
  88                         val = __unaligned_load(addr, 2);
  89                         __emul_store_reg(uf, IF_F3_RD(insn),
  90                             IF_SEXT(val, 16));
  91                         break;
  92                 case INS3_LDSW:
  93                         val = __unaligned_load(addr, 4);
  94                         __emul_store_reg(uf, IF_F3_RD(insn),
  95                             IF_SEXT(val, 32));
  96                         break;
  97                 case INS3_STH:
  98                         val = __emul_fetch_reg(uf, IF_F3_RD(insn));
  99                         __unaligned_store(addr, val, 2);
 100                         break;
 101                 case INS3_STW:
 102                         val = __emul_fetch_reg(uf, IF_F3_RD(insn));
 103                         __unaligned_store(addr, val, 4);
 104                         break;
 105                 case INS3_STX:
 106                         val = __emul_fetch_reg(uf, IF_F3_RD(insn));
 107                         __unaligned_store(addr, val, 8);
 108                         break;
 109                 default:
 110                         sig = SIGILL;
 111                         break;
 112                 }
 113                 break;
 114         default:
 115                 sig = SIGILL;
 116                 break;
 117         }
 118         return (sig);
 119 }