1 2 /*--------------------------------------------------------------------*/ 3 /*--- The core dispatch loop, for jumping to a code address. ---*/ 4 /*--- dispatch-amd64-linux.S ---*/ 5 /*--------------------------------------------------------------------*/ 6 7 /* 8 This file is part of Valgrind, a dynamic binary instrumentation 9 framework. 10 11 Copyright (C) 2000-2017 Julian Seward 12 jseward (at) 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 #include "pub_core_basics_asm.h" 33 34 #if defined(VGP_amd64_linux) 35 36 #include "pub_core_dispatch_asm.h" 37 #include "pub_core_transtab_asm.h" 38 #include "libvex_guest_offsets.h" /* for OFFSET_amd64_RIP */ 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 .text 59 .globl VG_(disp_run_translations) 60 .type VG_(disp_run_translations), @function 61 VG_(disp_run_translations): 62 /* %rdi holds two_words */ 63 /* %rsi holds guest_state */ 64 /* %rdx holds host_addr */ 65 66 /* The preamble */ 67 68 /* Save integer registers, since this is a pseudo-function. */ 69 pushq %rax 70 pushq %rbx 71 pushq %rcx 72 pushq %rdx 73 pushq %rsi 74 pushq %rbp 75 pushq %r8 76 pushq %r9 77 pushq %r10 78 pushq %r11 79 pushq %r12 80 pushq %r13 81 pushq %r14 82 pushq %r15 83 /* %rdi must be saved last */ 84 pushq %rdi 85 86 /* Get the host CPU in the state expected by generated code. */ 87 88 /* set host FPU control word to the default mode expected 89 by VEX-generated code. See comments in libvex.h for 90 more info. */ 91 finit 92 pushq $0x027F 93 fldcw (%rsp) 94 addq $8, %rsp 95 96 /* set host SSE control word to the default mode expected 97 by VEX-generated code. */ 98 pushq $0x1F80 99 ldmxcsr (%rsp) 100 addq $8, %rsp 101 102 /* set dir flag to known value */ 103 cld 104 105 /* Set up the guest state pointer */ 106 movq %rsi, %rbp 107 108 /* and jump into the code cache. Chained translations in 109 the code cache run, until for whatever reason, they can't 110 continue. When that happens, the translation in question 111 will jump (or call) to one of the continuation points 112 VG_(cp_...) below. */ 113 jmpq *%rdx 114 /*NOTREACHED*/ 115 116 /*----------------------------------------------------*/ 117 /*--- Postamble and exit. ---*/ 118 /*----------------------------------------------------*/ 119 120 postamble: 121 /* At this point, %rax and %rdx contain two 122 words to be returned to the caller. %rax 123 holds a TRC value, and %rdx optionally may 124 hold another word (for CHAIN_ME exits, the 125 address of the place to patch.) */ 126 127 /* We're leaving. Check that nobody messed with %mxcsr 128 or %fpucw. We can't mess with %rax or %rdx here as they 129 hold the tentative return values, but any others are OK. */ 130 #if !defined(ENABLE_INNER) 131 /* This check fails for self-hosting, so skip in that case */ 132 pushq $0 133 fstcw (%rsp) 134 cmpl $0x027F, (%rsp) 135 popq %r15 /* get rid of the word without trashing %rflags */ 136 jnz invariant_violation 137 #endif 138 pushq $0 139 stmxcsr (%rsp) 140 andl $0xFFFFFFC0, (%rsp) /* mask out status flags */ 141 cmpl $0x1F80, (%rsp) 142 popq %r15 143 jnz invariant_violation 144 /* otherwise we're OK */ 145 jmp remove_frame 146 invariant_violation: 147 movq $VG_TRC_INVARIANT_FAILED, %rax 148 movq $0, %rdx 149 150 remove_frame: 151 /* Pop %rdi, stash return values */ 152 popq %rdi 153 movq %rax, 0(%rdi) 154 movq %rdx, 8(%rdi) 155 /* Now pop everything else */ 156 popq %r15 157 popq %r14 158 popq %r13 159 popq %r12 160 popq %r11 161 popq %r10 162 popq %r9 163 popq %r8 164 popq %rbp 165 popq %rsi 166 popq %rdx 167 popq %rcx 168 popq %rbx 169 popq %rax 170 ret 171 172 /*----------------------------------------------------*/ 173 /*--- Continuation points ---*/ 174 /*----------------------------------------------------*/ 175 176 /* ------ Chain me to slow entry point ------ */ 177 .global VG_(disp_cp_chain_me_to_slowEP) 178 VG_(disp_cp_chain_me_to_slowEP): 179 /* We got called. The return address indicates 180 where the patching needs to happen. Collect 181 the return address and, exit back to C land, 182 handing the caller the pair (Chain_me_S, RA) */ 183 movq $VG_TRC_CHAIN_ME_TO_SLOW_EP, %rax 184 popq %rdx 185 /* 10 = movabsq $VG_(disp_chain_me_to_slowEP), %r11; 186 3 = call *%r11 */ 187 subq $10+3, %rdx 188 jmp postamble 189 190 /* ------ Chain me to fast entry point ------ */ 191 .global VG_(disp_cp_chain_me_to_fastEP) 192 VG_(disp_cp_chain_me_to_fastEP): 193 /* We got called. The return address indicates 194 where the patching needs to happen. Collect 195 the return address and, exit back to C land, 196 handing the caller the pair (Chain_me_F, RA) */ 197 movq $VG_TRC_CHAIN_ME_TO_FAST_EP, %rax 198 popq %rdx 199 /* 10 = movabsq $VG_(disp_chain_me_to_fastEP), %r11; 200 3 = call *%r11 */ 201 subq $10+3, %rdx 202 jmp postamble 203 204 /* ------ Indirect but boring jump ------ */ 205 .global VG_(disp_cp_xindir) 206 VG_(disp_cp_xindir): 207 /* Where are we going? */ 208 movq OFFSET_amd64_RIP(%rbp), %rax 209 210 /* stats only */ 211 addl $1, VG_(stats__n_xindirs_32) 212 213 /* try a fast lookup in the translation cache */ 214 movabsq $VG_(tt_fast), %rcx 215 movq %rax, %rbx /* next guest addr */ 216 andq $VG_TT_FAST_MASK, %rbx /* entry# */ 217 shlq $4, %rbx /* entry# * sizeof(FastCacheEntry) */ 218 movq 0(%rcx,%rbx,1), %r10 /* .guest */ 219 movq 8(%rcx,%rbx,1), %r11 /* .host */ 220 cmpq %rax, %r10 221 jnz fast_lookup_failed 222 223 /* Found a match. Jump to .host. */ 224 jmp *%r11 225 ud2 /* persuade insn decoders not to speculate past here */ 226 227 fast_lookup_failed: 228 /* stats only */ 229 addl $1, VG_(stats__n_xindir_misses_32) 230 231 movq $VG_TRC_INNER_FASTMISS, %rax 232 movq $0, %rdx 233 jmp postamble 234 235 /* ------ Assisted jump ------ */ 236 .global VG_(disp_cp_xassisted) 237 VG_(disp_cp_xassisted): 238 /* %rbp contains the TRC */ 239 movq %rbp, %rax 240 movq $0, %rdx 241 jmp postamble 242 243 /* ------ Event check failed ------ */ 244 .global VG_(disp_cp_evcheck_fail) 245 VG_(disp_cp_evcheck_fail): 246 movq $VG_TRC_INNER_COUNTERZERO, %rax 247 movq $0, %rdx 248 jmp postamble 249 250 251 .size VG_(disp_run_translations), .-VG_(disp_run_translations) 252 253 #endif // defined(VGP_amd64_linux) 254 255 /* Let the linker know we don't need an executable stack */ 256 MARK_STACK_NO_EXEC 257 258 /*--------------------------------------------------------------------*/ 259 /*--- end ---*/ 260 /*--------------------------------------------------------------------*/ 261
