1 2 /*--------------------------------------------------------------------*/ 3 /*--- The core dispatch loop, for jumping to a code address. ---*/ 4 /*--- dispatch-mips64-linux.S ---*/ 5 /*--------------------------------------------------------------------*/ 6 7 /* 8 This file is part of Valgrind, a dynamic binary instrumentation 9 framework. 10 11 Copyright (C) 2000-2015 RT-RK 12 mips-valgrind (at) rt-rk.com 13 14 This program is free software; you can redistribute it and/or 15 modify it under the terms of the GNU General Public License as 16 published by the Free Software Foundation; either version 2 of the 17 License, or (at your option) any later version. 18 19 This program is distributed in the hope that it will be useful, but 20 WITHOUT ANY WARRANTY; without even the implied warranty of 21 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 22 General Public License for more details. 23 24 You should have received a copy of the GNU General Public License 25 along with this program; if not, write to the Free Software 26 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 27 02111-1307, USA. 28 29 The GNU General Public License is contained in the file COPYING. 30 */ 31 32 #include "pub_core_basics_asm.h" 33 34 #if defined(VGP_mips64_linux) 35 36 #include "pub_core_dispatch_asm.h" 37 #include "pub_core_transtab_asm.h" 38 #include "libvex_guest_offsets.h" /* for OFFSET_mips_PC */ 39 40 41 /*------------------------------------------------------------*/ 42 /*--- ---*/ 43 /*--- The dispatch loop. VG_(disp_run_translations) is ---*/ 44 /*--- used to run all translations, ---*/ 45 /*--- including no-redir ones. ---*/ 46 /*--- ---*/ 47 /*------------------------------------------------------------*/ 48 49 /*----------------------------------------------------*/ 50 /*--- Entry and preamble (set everything up) ---*/ 51 /*----------------------------------------------------*/ 52 53 /* signature: 54 void VG_(disp_run_translations)( UWord* two_words, 55 void* guest_state, 56 Addr host_addr ); 57 */ 58 59 .text 60 .globl VG_(disp_run_translations) 61 VG_(disp_run_translations): 62 /* a0 ($4) holds two_words */ 63 /* a1 ($5) holds guest_state */ 64 /* a2 ($6) holds host_addr */ 65 66 /* New stack frame. Stack must remain 16 aligned (at least) */ 67 daddiu $29, -176 68 69 /* Save ra */ 70 sd $31, 72($29) 71 72 /* ... and s0 - s7 */ 73 sd $16, 80($29) 74 sd $17, 88($29) 75 sd $18, 96($29) 76 sd $19, 104($29) 77 sd $20, 112($29) 78 sd $21, 120($29) 79 sd $22, 128($29) 80 sd $23, 136($29) 81 82 /* ... and gp, fp/s8 */ 83 sd $28, 144($29) 84 sd $30, 152($29) 85 86 /* Save a0 ($4) on stack. In postamble it will be restored such that the 87 return values can be written */ 88 sd $4, 160($29) 89 90 /* Load address of guest state into guest state register ($23) */ 91 move $23, $5 92 93 /* and jump into the code cache. Chained translations in 94 the code cache run, until for whatever reason, they can't 95 continue. When that happens, the translation in question 96 will jump (or call) to one of the continuation points 97 VG_(cp_...) below. */ 98 jr $6 99 /*NOTREACHED*/ 100 101 /*----------------------------------------------------*/ 102 /*--- Postamble and exit. ---*/ 103 /*----------------------------------------------------*/ 104 105 postamble: 106 /* At this point, $2 and $3 contain two 107 words to be returned to the caller. $2 108 holds a TRC value, and $3 optionally may 109 hold another word (for CHAIN_ME exits, the 110 address of the place to patch.) */ 111 112 /* Restore $4 from stack; holds address of two_words */ 113 ld $4, 160($29) 114 sd $2, 0($4) /* Store $2 to two_words[0] */ 115 sd $3, 8($4) /* Store $3 to two_words[1] */ 116 117 /* Restore callee-saved registers... */ 118 119 /* Restore ra */ 120 ld $31, 72($29) 121 122 /* ... and s0 - s7 */ 123 ld $16, 80($29) 124 ld $17, 88($29) 125 ld $18, 96($29) 126 ld $19, 104($29) 127 ld $20, 112($29) 128 ld $21, 120($29) 129 ld $22, 128($29) 130 ld $23, 136($29) 131 132 /* ... and gp, fp/s8 */ 133 ld $28, 144($29) 134 ld $30, 152($29) 135 136 daddiu $29, 176 /* stack_size */ 137 jr $31 138 nop 139 140 /*----------------------------------------------------*/ 141 /*--- Continuation points ---*/ 142 /*----------------------------------------------------*/ 143 144 /* ------ Chain me to slow entry point ------ */ 145 .global VG_(disp_cp_chain_me_to_slowEP) 146 VG_(disp_cp_chain_me_to_slowEP): 147 /* We got called. The return address indicates 148 where the patching needs to happen. Collect 149 the return address and, exit back to C land, 150 handing the caller the pair (Chain_me_S, RA) */ 151 li $2, VG_TRC_CHAIN_ME_TO_SLOW_EP 152 move $3, $31 153 /* 8 = mkLoadImm_EXACTLY2or6 154 4 = jalr $9 155 4 = nop */ 156 daddiu $3, $3, -32 157 b postamble 158 159 /* ------ Chain me to slow entry point ------ */ 160 .global VG_(disp_cp_chain_me_to_fastEP) 161 VG_(disp_cp_chain_me_to_fastEP): 162 /* We got called. The return address indicates 163 where the patching needs to happen. Collect 164 the return address and, exit back to C land, 165 handing the caller the pair (Chain_me_S, RA) */ 166 li $2, VG_TRC_CHAIN_ME_TO_FAST_EP 167 move $3, $31 168 /* 8 = mkLoadImm_EXACTLY2or6 169 4 = jalr $9 170 4 = nop */ 171 daddiu $3, $3, -32 172 b postamble 173 174 /* ------ Indirect but boring jump ------ */ 175 .global VG_(disp_cp_xindir) 176 VG_(disp_cp_xindir): 177 /* Where are we going? */ 178 ld $11, OFFSET_mips64_PC($23) 179 180 lw $13, vgPlain_stats__n_xindirs_32 181 addiu $13, $13, 0x1 182 sw $13, vgPlain_stats__n_xindirs_32 183 184 /* try a fast lookup in the translation cache */ 185 /* t1 = VG_TT_FAST_HASH(addr) * sizeof(ULong*) 186 = (t8 >> 2 & VG_TT_FAST_MASK) << 3 */ 187 188 move $14, $11 189 li $12, VG_TT_FAST_MASK 190 srl $14, $14, 2 191 and $14, $14, $12 192 sll $14, $14, 3 193 194 /* t2 = (addr of VG_(tt_fast)) + t1 */ 195 dla $13, VG_(tt_fast) 196 daddu $13, $13, $14 197 198 ld $12, 0($13) /* t3 = VG_(tt_fast)[hash] :: ULong* */ 199 daddi $13, $13, 8 200 ld $25, 0($13) /* little-endian, so comparing 1st 32bit word */ 201 nop 202 203 check: 204 bne $12, $11, fast_lookup_failed 205 /* run the translation */ 206 jr $25 207 .long 0x0 /* persuade insn decoders not to speculate past here */ 208 209 fast_lookup_failed: 210 /* %PC is up to date */ 211 /* back out decrement of the dispatch counter */ 212 /* hold dispatch_ctr in t0 (r8) */ 213 lw $13, vgPlain_stats__n_xindirs_32 214 addiu $13, $13, 0x1 215 sw $13, vgPlain_stats__n_xindirs_32 216 li $2, VG_TRC_INNER_FASTMISS 217 li $3, 0 218 b postamble 219 220 /* ------ Assisted jump ------ */ 221 .global VG_(disp_cp_xassisted) 222 VG_(disp_cp_xassisted): 223 /* guest-state-pointer contains the TRC. Put the value into the 224 return register */ 225 move $2, $23 226 move $3, $0 227 b postamble 228 229 /* ------ Event check failed ------ */ 230 .global VG_(disp_cp_evcheck_fail) 231 VG_(disp_cp_evcheck_fail): 232 li $2, VG_TRC_INNER_COUNTERZERO 233 move $3, $0 234 b postamble 235 236 .size VG_(disp_run_translations), .-VG_(disp_run_translations) 237 238 #endif // defined(VGP_mips64_linux) 239 240 /* Let the linker know we don't need an executable stack */ 241 MARK_STACK_NO_EXEC 242 243 /*--------------------------------------------------------------------*/ 244 /*--- end ---*/ 245 /*--------------------------------------------------------------------*/ 246
