1 2 /*---------------------------------------------------------------*/ 3 /*--- begin guest_arm_defs.h ---*/ 4 /*---------------------------------------------------------------*/ 5 /* 6 This file is part of Valgrind, a dynamic binary instrumentation 7 framework. 8 9 Copyright (C) 2004-2011 OpenWorks LLP 10 info@open-works.net 11 12 This program is free software; you can redistribute it and/or 13 modify it under the terms of the GNU General Public License as 14 published by the Free Software Foundation; either version 2 of the 15 License, or (at your option) any later version. 16 17 This program is distributed in the hope that it will be useful, but 18 WITHOUT ANY WARRANTY; without even the implied warranty of 19 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 20 General Public License for more details. 21 22 You should have received a copy of the GNU General Public License 23 along with this program; if not, write to the Free Software 24 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 25 02110-1301, USA. 26 27 The GNU General Public License is contained in the file COPYING. 28 */ 29 30 /* Only to be used within the guest-arm directory. */ 31 32 #ifndef __VEX_GUEST_ARM_DEFS_H 33 #define __VEX_GUEST_ARM_DEFS_H 34 35 36 /*---------------------------------------------------------*/ 37 /*--- arm to IR conversion ---*/ 38 /*---------------------------------------------------------*/ 39 40 /* Convert one ARM insn to IR. See the type DisOneInstrFn in 41 bb_to_IR.h. */ 42 extern 43 DisResult disInstr_ARM ( IRSB* irbb, 44 Bool put_IP, 45 Bool (*resteerOkFn) ( void*, Addr64 ), 46 Bool resteerCisOk, 47 void* callback_opaque, 48 UChar* guest_code, 49 Long delta, 50 Addr64 guest_IP, 51 VexArch guest_arch, 52 VexArchInfo* archinfo, 53 VexAbiInfo* abiinfo, 54 Bool host_bigendian ); 55 56 /* Used by the optimiser to specialise calls to helpers. */ 57 extern 58 IRExpr* guest_arm_spechelper ( HChar* function_name, 59 IRExpr** args, 60 IRStmt** precedingStmts, 61 Int n_precedingStmts ); 62 63 /* Describes to the optimser which part of the guest state require 64 precise memory exceptions. This is logically part of the guest 65 state description. */ 66 extern 67 Bool guest_arm_state_requires_precise_mem_exns ( Int, Int ); 68 69 extern 70 VexGuestLayout armGuest_layout; 71 72 73 /*---------------------------------------------------------*/ 74 /*--- arm guest helpers ---*/ 75 /*---------------------------------------------------------*/ 76 77 /* --- CLEAN HELPERS --- */ 78 79 /* Calculate NZCV from the supplied thunk components, in the positions 80 they appear in the CPSR, viz bits 31:28 for N Z V C respectively. 81 Returned bits 27:0 are zero. */ 82 extern 83 UInt armg_calculate_flags_nzcv ( UInt cc_op, UInt cc_dep1, 84 UInt cc_dep2, UInt cc_dep3 ); 85 86 /* Calculate the C flag from the thunk components, in the lowest bit 87 of the word (bit 0). */ 88 extern 89 UInt armg_calculate_flag_c ( UInt cc_op, UInt cc_dep1, 90 UInt cc_dep2, UInt cc_dep3 ); 91 92 /* Calculate the V flag from the thunk components, in the lowest bit 93 of the word (bit 0). */ 94 extern 95 UInt armg_calculate_flag_v ( UInt cc_op, UInt cc_dep1, 96 UInt cc_dep2, UInt cc_dep3 ); 97 98 /* Calculate the specified condition from the thunk components, in the 99 lowest bit of the word (bit 0). */ 100 extern 101 UInt armg_calculate_condition ( UInt cond_n_op /* ARMCondcode << 4 | cc_op */, 102 UInt cc_dep1, 103 UInt cc_dep2, UInt cc_dep3 ); 104 105 /* Calculate the QC flag from the thunk components, in the lowest bit 106 of the word (bit 0). */ 107 extern 108 UInt armg_calculate_flag_qc ( UInt resL1, UInt resL2, 109 UInt resR1, UInt resR2 ); 110 111 112 /*---------------------------------------------------------*/ 113 /*--- Condition code stuff ---*/ 114 /*---------------------------------------------------------*/ 115 116 /* Flags masks. Defines positions of flags bits in the CPSR. */ 117 #define ARMG_CC_SHIFT_N 31 118 #define ARMG_CC_SHIFT_Z 30 119 #define ARMG_CC_SHIFT_C 29 120 #define ARMG_CC_SHIFT_V 28 121 #define ARMG_CC_SHIFT_Q 27 122 123 #define ARMG_CC_MASK_N (1 << ARMG_CC_SHIFT_N) 124 #define ARMG_CC_MASK_Z (1 << ARMG_CC_SHIFT_Z) 125 #define ARMG_CC_MASK_C (1 << ARMG_CC_SHIFT_C) 126 #define ARMG_CC_MASK_V (1 << ARMG_CC_SHIFT_V) 127 #define ARMG_CC_MASK_Q (1 << ARMG_CC_SHIFT_Q) 128 129 /* Flag thunk descriptors. A four-word thunk is used to record 130 details of the most recent flag-setting operation, so NZCV can 131 be computed later if needed. 132 133 The four words are: 134 135 CC_OP, which describes the operation. 136 137 CC_DEP1, CC_DEP2, CC_DEP3. These are arguments to the 138 operation. We want set up the mcx_masks in flag helper calls 139 involving these fields so that Memcheck "believes" that the 140 resulting flags are data-dependent on both CC_DEP1 and 141 CC_DEP2. Hence the name DEP. 142 143 When building the thunk, it is always necessary to write words into 144 CC_DEP1/2/3, even if those args are not used given the 145 CC_OP field. This is important because otherwise Memcheck could 146 give false positives as it does not understand the relationship 147 between the CC_OP field and CC_DEP1/2/3, and so believes 148 that the definedness of the stored flags always depends on 149 all 3 DEP values. 150 151 Fields carrying only 1 or 2 bits of useful information (old_C, 152 shifter_co, old_V, oldC:oldV) must have their top 31 or 30 bits 153 (respectively) zero. The text "31x0:" or "30x0:" denotes this. 154 155 A summary of the field usages is: 156 157 OP DEP1 DEP2 DEP3 158 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 159 160 OP_COPY current NZCV unused unused 161 OP_ADD argL argR unused 162 OP_SUB argL argR unused 163 OP_ADC argL argR 31x0:old_C 164 OP_SBB argL argR 31x0:old_C 165 OP_LOGIC result 31x0:shifter_co 31x0:old_V 166 OP_MUL result unused 30x0:old_C:old_V 167 OP_MULL resLO32 resHI32 30x0:old_C:old_V 168 */ 169 170 enum { 171 ARMG_CC_OP_COPY=0, /* DEP1 = NZCV in 31:28, DEP2 = 0, DEP3 = 0 172 just copy DEP1 to output */ 173 174 ARMG_CC_OP_ADD, /* DEP1 = argL (Rn), DEP2 = argR (shifter_op), 175 DEP3 = 0 */ 176 177 ARMG_CC_OP_SUB, /* DEP1 = argL (Rn), DEP2 = argR (shifter_op), 178 DEP3 = 0 */ 179 180 ARMG_CC_OP_ADC, /* DEP1 = argL (Rn), DEP2 = arg2 (shifter_op), 181 DEP3 = oldC (in LSB) */ 182 183 ARMG_CC_OP_SBB, /* DEP1 = argL (Rn), DEP2 = arg2 (shifter_op), 184 DEP3 = oldC (in LSB) */ 185 186 ARMG_CC_OP_LOGIC, /* DEP1 = result, DEP2 = shifter_carry_out (in LSB), 187 DEP3 = old V flag (in LSB) */ 188 189 ARMG_CC_OP_MUL, /* DEP1 = result, DEP2 = 0, DEP3 = oldC:old_V 190 (in bits 1:0) */ 191 192 ARMG_CC_OP_MULL, /* DEP1 = resLO32, DEP2 = resHI32, DEP3 = oldC:old_V 193 (in bits 1:0) */ 194 195 ARMG_CC_OP_NUMBER 196 }; 197 198 /* XXXX because of the calling conventions for 199 armg_calculate_condition, all this OP values MUST be in the range 200 0 .. 15 only (viz, 4-bits). */ 201 202 203 204 /* Defines conditions which we can ask for (ARM ARM 2e page A3-6) */ 205 206 typedef 207 enum { 208 ARMCondEQ = 0, /* equal : Z=1 */ 209 ARMCondNE = 1, /* not equal : Z=0 */ 210 211 ARMCondHS = 2, /* >=u (higher or same) : C=1 */ 212 ARMCondLO = 3, /* <u (lower) : C=0 */ 213 214 ARMCondMI = 4, /* minus (negative) : N=1 */ 215 ARMCondPL = 5, /* plus (zero or +ve) : N=0 */ 216 217 ARMCondVS = 6, /* overflow : V=1 */ 218 ARMCondVC = 7, /* no overflow : V=0 */ 219 220 ARMCondHI = 8, /* >u (higher) : C=1 && Z=0 */ 221 ARMCondLS = 9, /* <=u (lower or same) : C=0 || Z=1 */ 222 223 ARMCondGE = 10, /* >=s (signed greater or equal) : N=V */ 224 ARMCondLT = 11, /* <s (signed less than) : N!=V */ 225 226 ARMCondGT = 12, /* >s (signed greater) : Z=0 && N=V */ 227 ARMCondLE = 13, /* <=s (signed less or equal) : Z=1 || N!=V */ 228 229 ARMCondAL = 14, /* always (unconditional) : 1 */ 230 ARMCondNV = 15 /* never (unconditional): : 0 */ 231 /* NB: ARM have deprecated the use of the NV condition code. 232 You are now supposed to use MOV R0,R0 as a noop rather than 233 MOVNV R0,R0 as was previously recommended. Future processors 234 may have the NV condition code reused to do other things. */ 235 } 236 ARMCondcode; 237 238 #endif /* ndef __VEX_GUEST_ARM_DEFS_H */ 239 240 /*---------------------------------------------------------------*/ 241 /*--- end guest_arm_defs.h ---*/ 242 /*---------------------------------------------------------------*/ 243