1 2/*--------------------------------------------------------------------*/ 3/*--- The core dispatch loop, for jumping to a code address. ---*/ 4/*--- dispatch-s390x-linux.S ---*/ 5/*--------------------------------------------------------------------*/ 6 7/* 8 This file is part of Valgrind, a dynamic binary instrumentation 9 framework. 10 11 Copyright IBM Corp. 2010-2017 12 Copyright (C) 2011-2017, Florian Krohm (britzel@acm.org) 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/* Contributed by Florian Krohm and Christian Borntraeger */ 33 34#include "pub_core_basics_asm.h" 35#include "pub_core_dispatch_asm.h" 36#include "pub_core_transtab_asm.h" 37#include "libvex_guest_offsets.h" 38#include "libvex_s390x_common.h" 39 40#if defined(VGA_s390x) 41 42/*------------------------------------------------------------*/ 43/*--- ---*/ 44/*--- The dispatch loop. VG_(disp_run_translations) is ---*/ 45/*--- used to run all translations, ---*/ 46/*--- including no-redir ones. ---*/ 47/*--- ---*/ 48/*------------------------------------------------------------*/ 49 50/* Convenience definitions for readability */ 51#undef SP 52#define SP S390_REGNO_STACK_POINTER 53 54#undef LR 55#define LR S390_REGNO_LINK_REGISTER 56 57/* Location of valgrind's saved FPC register */ 58#define S390_LOC_SAVED_FPC_V S390_OFFSET_SAVED_FPC_V(SP) 59 60/* Location of saved R2 register */ 61#define S390_LOC_SAVED_R2 S390_OFFSET_SAVED_R2(SP) 62 63 64/*----------------------------------------------------*/ 65/*--- Entry and preamble (set everything up) ---*/ 66/*----------------------------------------------------*/ 67 68/* signature: 69void VG_(disp_run_translations)( UWord* two_words, 70 void* guest_state, 71 Addr host_addr ); 72 73 Return results are placed in two_words: 74 75 two_words[0] is set to the TRC 76 two_words[1] is set to the address to patch (in case two_words[0] is 77 VG_TRC_CHAIN_ME_TO_{SLOW,FAST}_EP). Otherwise, it is 0. 78*/ 79 .text 80 .align 4 81 .globl VG_(disp_run_translations) 82 .type VG_(disp_run_translations), @function 83VG_(disp_run_translations): 84 85 /* r2 holds two_words */ 86 /* r3 holds pointer to guest_state */ 87 /* r4 holds host_addr, i.e. the address of the translation to run */ 88 89 /* Save gprs ABI: r6...r13 and r15 */ 90 stmg %r6,%r15,48(SP) 91 92 /* New stack frame */ 93 aghi SP,-S390_INNERLOOP_FRAME_SIZE 94 95 /* Save fprs: ABI: f8...f15 */ 96 std %f8,160+0(SP) 97 std %f9,160+8(SP) 98 std %f10,160+16(SP) 99 std %f11,160+24(SP) 100 std %f12,160+32(SP) 101 std %f13,160+40(SP) 102 std %f14,160+48(SP) 103 std %f15,160+56(SP) 104 105 /* Load address of guest state into guest state register (r13) */ 106 lgr %r13,%r3 107 108 /* Save R2 on stack. In postamble it will be restored such that the 109 return values can be written */ 110 stg %r2,S390_LOC_SAVED_R2 111 112 /* Save valgrind's FPC on stack so postamble can restore 113 it later . */ 114 stfpc S390_LOC_SAVED_FPC_V 115 116 /* Load the FPC the way the client code wants it. I.e. pull the 117 value from the guest state. */ 118 lfpc OFFSET_s390x_fpc(%r13) 119 120 /* Jump into the code cache. Chained translations in 121 the code cache run, until for whatever reason, they can't 122 continue. When that happens, the translation in question 123 will jump (or call) to one of the continuation points 124 VG_(cp_...) below. */ 125 br %r4 126 127 128/*----------------------------------------------------*/ 129/*--- Postamble and return to C code. ---*/ 130/*----------------------------------------------------*/ 131 132postamble: 133 /* At this point, %r0 and %r1 contain two 134 words to be returned to the caller. %r0 135 holds a TRC value, and %r1 optionally may 136 hold another word (for CHAIN_ME exits, the 137 address of the place to patch.) */ 138 139 /* We're leaving. AMD has some code here to check invariants. 140 We don't have (need) that, as we save and restore the FPC register 141 whenever we switch between valgrind proper to client code. */ 142 143 /* Restore valgrind's FPC, as client code may have changed it. */ 144 lfpc S390_LOC_SAVED_FPC_V 145 146 /* Restore %r2 from stack; holds address of two_words */ 147 lg %r2,S390_LOC_SAVED_R2 148 149 stg %r0,0(%r2) /* Store %r0 to two_words[0] */ 150 stg %r1,8(%r2) /* Store %r1 to two_words[1] */ 151 152 /* Restore callee-saved registers... */ 153 154 /* Floating-point regs */ 155 ld %f8,160+0(SP) 156 ld %f9,160+8(SP) 157 ld %f10,160+16(SP) 158 ld %f11,160+24(SP) 159 ld %f12,160+32(SP) 160 ld %f13,160+40(SP) 161 ld %f14,160+48(SP) 162 ld %f15,160+56(SP) 163 164 /* Remove stack frame */ 165 aghi SP,S390_INNERLOOP_FRAME_SIZE 166 167 /* General-purpose regs. This also restores the original link 168 register (r14) and stack pointer (r15). */ 169 lmg %r6,%r15,48(SP) 170 171 /* Return */ 172 br LR 173 174 175/*----------------------------------------------------*/ 176/*--- Continuation points ---*/ 177/*----------------------------------------------------*/ 178 179/* ------ Chain me to slow entry point ------ */ 180 .global VG_(disp_cp_chain_me_to_slowEP) 181VG_(disp_cp_chain_me_to_slowEP): 182 /* When we come here %r1 contains the address of the place to patch. 183 The return values (TRC, address-to-patch) are stored here in 184 %r0 and %r1, respectively */ 185 lghi %r0,VG_TRC_CHAIN_ME_TO_SLOW_EP 186 j postamble 187 188 189/* ------ Chain me to fast entry point ------ */ 190 .global VG_(disp_cp_chain_me_to_fastEP) 191VG_(disp_cp_chain_me_to_fastEP): 192 /* Identical to VG_(disp_cp_chain_me_to_slowEP), except value of %r0. */ 193 lghi %r0,VG_TRC_CHAIN_ME_TO_FAST_EP 194 j postamble 195 196 197/* ------ Indirect but boring jump ------ */ 198 .global VG_(disp_cp_xindir) 199VG_(disp_cp_xindir): 200 /* Where are we going? */ 201 lg %r2, OFFSET_s390x_IA(%r13) 202 203 /* Increment VG_(stats__n_xindirs_32) */ 204 larl %r8, VG_(stats__n_xindirs_32) 205 l %r10,0(%r8) 206 ahi %r10,1 207 st %r10,0(%r8) 208 209 /* Try a fast lookup in the translation cache: 210 Compute offset (not index) into VT_(tt_fast): 211 212 offset = VG_TT_FAST_HASH(addr) * sizeof(FastCacheEntry) 213 214 with VG_TT_FAST_HASH(addr) == (addr >> 1) & VG_TT_FAST_MASK 215 and sizeof(FastCacheEntry) == 16 216 217 offset = ((addr >> 1) & VG_TT_FAST_MASK) << 4 218 which is 219 offset = ((addr & (VG_TT_FAST_MASK << 1) ) << 3 220 */ 221 larl %r8, VG_(tt_fast) 222 llill %r5,(VG_TT_FAST_MASK << 1) & 0xffff 223#if ((( VG_TT_FAST_MASK << 1) & 0xffff0000) >> 16 != 0) 224 iilh %r5,((VG_TT_FAST_MASK << 1) & 0xffff0000) >> 16 225#endif 226 ngr %r5,%r2 227 sllg %r7,%r5,3 228 lg %r11, 8(%r8,%r7) /* .host */ 229 cg %r2, 0(%r8,%r7) /* next guest address == .guest ? */ 230 jne fast_lookup_failed 231 232 /* Found a match. Call .host. 233 r11 is an address. There we will find the instrumented client code. 234 That code may modify the guest state register r13. */ 235 br %r11 236 .long 0x0 /* persuade insn decoders not to speculate past here */ 237 238fast_lookup_failed: 239 /* Increment VG_(stats__n_xindir_misses_32) */ 240 larl %r8, VG_(stats__n_xindir_misses_32) 241 l %r10,0(%r8) 242 ahi %r10,1 243 st %r10,0(%r8) 244 245 lghi %r0,VG_TRC_INNER_FASTMISS 246 lghi %r1,0 247 j postamble 248 249 250/* ------ Assisted jump ------ */ 251 .global VG_(disp_cp_xassisted) 252VG_(disp_cp_xassisted): 253 /* guest-state-pointer contains the TRC. Put the value into the 254 return register */ 255 lgr %r0,%r13 256 lghi %r1,0 257 j postamble 258 259 260/* ------ Event check failed ------ */ 261 .global VG_(disp_cp_evcheck_fail) 262VG_(disp_cp_evcheck_fail): 263 lghi %r0,VG_TRC_INNER_COUNTERZERO 264 lghi %r1,0 265 j postamble 266 267 268 .size VG_(disp_run_translations), .-VG_(disp_run_translations) 269 270#endif /* VGA_s390x */ 271 272/* Let the linker know we don't need an executable stack */ 273MARK_STACK_NO_EXEC 274 275/*--------------------------------------------------------------------*/ 276/*--- end dispatch-s390x-linux.S ---*/ 277/*--------------------------------------------------------------------*/ 278