diff options
| -rw-r--r-- | disasm.c | 118 |
1 files changed, 107 insertions, 11 deletions
@@ -197,6 +197,76 @@ static enum reg_enum whichreg(opflags_t regflags, int regval, int rex) } /* + * Find N value for compressed displacement (disp8 * N) + */ +static uint8_t get_disp8N(insn *ins) +{ + const uint8_t fv_n[2][2][VLMAX] = {{{16, 32, 64}, {4, 4, 4}}, + {{16, 32, 64}, {8, 8, 8}}}; + const uint8_t hv_n[2][VLMAX] = {{8, 16, 32}, {4, 4, 4}}; + const uint8_t dup_n[VLMAX] = {8, 32, 64}; + + bool evex_b = (ins->evex_p[2] & EVEX_P2B) >> 4; + enum ttypes tuple = ins->evex_tuple; + /* vex_wlp composed as [wwllpp] */ + enum vectlens vectlen = (ins->evex_p[2] & EVEX_P2LL) >> 5; + /* wig(=2) is treated as w0(=0) */ + bool evex_w = (ins->evex_p[1] & EVEX_P1W) >> 7; + uint8_t n = 0; + + switch(tuple) { + case FV: + n = fv_n[evex_w][evex_b][vectlen]; + break; + case HV: + n = hv_n[evex_b][vectlen]; + break; + + case FVM: + /* 16, 32, 64 for VL 128, 256, 512 respectively*/ + n = 1 << (vectlen + 4); + break; + case T1S8: /* N = 1 */ + case T1S16: /* N = 2 */ + n = tuple - T1S8 + 1; + break; + case T1S: + /* N = 4 for 32bit, 8 for 64bit */ + n = evex_w ? 8 : 4; + break; + case T1F32: + case T1F64: + /* N = 4 for 32bit, 8 for 64bit */ + n = (tuple == T1F32 ? 4 : 8); + break; + case T2: + case T4: + case T8: + if (vectlen + 7 <= (evex_w + 5) + (tuple - T2 + 1)) + n = 0; + else + n = 1 << (tuple - T2 + evex_w + 3); + break; + case HVM: + case QVM: + case OVM: + n = 1 << (OVM - tuple + vectlen + 1); + break; + case M128: + n = 16; + break; + case DUP: + n = dup_n[vectlen]; + break; + + default: + break; + } + + return n; +} + +/* * Process an effective address (ModRM) specification. */ static uint8_t *do_ea(uint8_t *data, int modrm, int asize, @@ -285,7 +355,12 @@ static uint8_t *do_ea(uint8_t *data, int modrm, int asize, break; case 1: op->segment |= SEG_DISP8; - op->offset = (int8_t)*data++; + if (ins->evex_tuple != 0) { + op->offset = gets8(data) * get_disp8N(ins); + } else { + op->offset = gets8(data); + } + data++; break; case 2: op->segment |= SEG_DISP16; @@ -371,7 +446,11 @@ static uint8_t *do_ea(uint8_t *data, int modrm, int asize, break; case 1: op->segment |= SEG_DISP8; - op->offset = gets8(data); + if (ins->evex_tuple != 0) { + op->offset = gets8(data) * get_disp8N(ins); + } else { + op->offset = gets8(data); + } data++; break; case 2: @@ -414,6 +493,7 @@ static int matches(const struct itemplate *t, uint8_t *data, (segsize == 64 ? SEG_64BIT : segsize == 32 ? SEG_32BIT : 0); } ins->condition = -1; + ins->evex_tuple = 0; ins->rex = prefix->rex; memset(ins->prefixes, 0, sizeof ins->prefixes); @@ -1023,6 +1103,7 @@ int32_t disasm(uint8_t *data, char *output, int outbufsize, int segsize, int best_pref; struct prefix_info prefix; bool end_prefix; + bool is_evex; memset(&ins, 0, sizeof ins); @@ -1289,6 +1370,7 @@ int32_t disasm(uint8_t *data, char *output, int outbufsize, int segsize, nasm_insn_names[i]); colon = false; + is_evex = !!(ins.rex & REX_EV); length += data - origdata; /* fix up for prefixes */ for (i = 0; i < (*p)->operands; i++) { opflags_t t = (*p)->opd[i]; @@ -1435,17 +1517,31 @@ int32_t disasm(uint8_t *data, char *output, int outbufsize, int segsize, if (o->segment & SEG_DISP8) { - const char *prefix; - uint8_t offset = offs; - if ((int8_t)offset < 0) { - prefix = "-"; - offset = -offset; + if (is_evex) { + const char *prefix; + uint32_t offset = offs; + if ((int32_t)offset < 0) { + prefix = "-"; + offset = -offset; + } else { + prefix = "+"; + } + slen += + snprintf(output + slen, outbufsize - slen, "%s0x%"PRIx32"", + prefix, offset); } else { - prefix = "+"; + const char *prefix; + uint8_t offset = offs; + if ((int8_t)offset < 0) { + prefix = "-"; + offset = -offset; + } else { + prefix = "+"; + } + slen += + snprintf(output + slen, outbufsize - slen, "%s0x%"PRIx8"", + prefix, offset); } - slen += - snprintf(output + slen, outbufsize - slen, "%s0x%"PRIx8"", - prefix, offset); } else if (o->segment & SEG_DISP16) { const char *prefix; uint16_t offset = offs; |