lib/libc/sparc64/sys/__sparc_utrap_align.c

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