From 5e0423804a6e421e0e8a22631eab42c984502f25 Mon Sep 17 00:00:00 2001 From: Jan Beulich Date: Tue, 30 Mar 2021 14:09:41 +0200 Subject: [PATCH] x86: drop seg_entry Use struct reg_entry instead for most purposes, with a separate array holding just the respective opcode prefix bytes. --- gas/ChangeLog | 15 +++++++++ gas/config/tc-i386-intel.c | 14 +++------ gas/config/tc-i386.c | 62 +++++++++++++++++--------------------- opcodes/ChangeLog | 7 +++++ opcodes/i386-opc.c | 16 +++++----- opcodes/i386-opc.h | 15 +-------- 6 files changed, 63 insertions(+), 66 deletions(-) diff --git a/gas/ChangeLog b/gas/ChangeLog index 210a93858d4..354a14be15d 100644 --- a/gas/ChangeLog +++ b/gas/ChangeLog @@ -1,3 +1,18 @@ +2021-03-30 Jan Beulich + + * config/tc-i386.c (build_modrm_byte): Change return type. + Change type of "default_seg". Use NULL. Adjust setting of + "default_seg". + (reg_ds, reg_es, reg_ss): New. + (struct _i386_insn): Change type of seg[]. + (md_begin): Initialize reg_ds, reg_es, and reg_ss. + (swap_operands): Change type of "temp_seg". + (check_string): Adjust %es check. + (process_operands): Change type of "default_seg". Use NULL. + Adjust segment override processing.. + (i386_att_operand): Adjust segment override handling. + * config/tc-i386-intel.c (i386_intel_operand): Likewise. + 2021-03-30 Jan Beulich * config/tc-i386.c (reg_eax): New. diff --git a/gas/config/tc-i386-intel.c b/gas/config/tc-i386-intel.c index e61e7572fc9..f9b44a46842 100644 --- a/gas/config/tc-i386-intel.c +++ b/gas/config/tc-i386-intel.c @@ -1028,16 +1028,10 @@ i386_intel_operand (char *operand_string, int got_a_float) as_warn (_("redundant segment overrides")); break; } - switch (i386_regtab[expP->X_add_number].reg_num) - { - case 0: i.seg[i.mem_operands] = &es; break; - case 1: i.seg[i.mem_operands] = &cs; break; - case 2: i.seg[i.mem_operands] = &ss; break; - case 3: i.seg[i.mem_operands] = &ds; break; - case 4: i.seg[i.mem_operands] = &fs; break; - case 5: i.seg[i.mem_operands] = &gs; break; - case RegFlat: i.seg[i.mem_operands] = NULL; break; - } + if (i386_regtab[expP->X_add_number].reg_num == RegFlat) + i.seg[i.mem_operands] = NULL; + else + i.seg[i.mem_operands] = &i386_regtab[expP->X_add_number]; } if (!i386_index_check (operand_string)) diff --git a/gas/config/tc-i386.c b/gas/config/tc-i386.c index 7fa31dab553..9c3d9785034 100644 --- a/gas/config/tc-i386.c +++ b/gas/config/tc-i386.c @@ -190,7 +190,7 @@ static int check_qword_reg (void); static int check_word_reg (void); static int finalize_imm (void); static int process_operands (void); -static const seg_entry *build_modrm_byte (void); +static const reg_entry *build_modrm_byte (void); static void output_insn (void); static void output_imm (fragS *, offsetT); static void output_disp (fragS *, offsetT); @@ -215,6 +215,9 @@ static const reg_entry bad_reg = { "", OPERAND_TYPE_NONE, 0, 0, { Dw2Inval, Dw2Inval } }; static const reg_entry *reg_eax; +static const reg_entry *reg_ds; +static const reg_entry *reg_es; +static const reg_entry *reg_ss; static const reg_entry *reg_st0; static const reg_entry *reg_k0; @@ -308,7 +311,7 @@ struct _i386_insn /* SEG gives the seg_entries of this insn. They are zero unless explicit segment overrides are given. */ - const seg_entry *seg[2]; + const reg_entry *seg[2]; /* Copied first memory operand string, for re-checking. */ char *memop1_string; @@ -3107,6 +3110,15 @@ md_begin (void) } break; + case SReg: + switch (regtab->reg_num) + { + case 0: reg_es = regtab; break; + case 2: reg_ss = regtab; break; + case 3: reg_ds = regtab; break; + } + break; + case RegMask: if (!regtab->reg_num) reg_k0 = regtab; @@ -5522,7 +5534,7 @@ swap_operands (void) if (i.mem_operands == 2) { - const seg_entry *temp_seg; + const reg_entry *temp_seg; temp_seg = i.seg[0]; i.seg[0] = i.seg[1]; i.seg[1] = temp_seg; @@ -6752,7 +6764,7 @@ check_string (void) unsigned int es_op = i.tm.opcode_modifier.isstring - IS_STRING_ES_OP0; unsigned int op = i.tm.operand_types[0].bitfield.baseindex ? es_op : 0; - if (i.seg[op] != NULL && i.seg[op] != &es) + if (i.seg[op] != NULL && i.seg[op] != reg_es) { as_bad (_("`%s' operand %u must use `%ses' segment"), i.tm.name, @@ -7543,7 +7555,7 @@ process_operands (void) /* Default segment register this instruction will use for memory accesses. 0 means unknown. This is only for optimizing out unnecessary segment overrides. */ - const seg_entry *default_seg = 0; + const reg_entry *default_seg = NULL; if (i.tm.opcode_modifier.sse2avx) { @@ -7730,13 +7742,13 @@ process_operands (void) else if (i.tm.opcode_modifier.opcodespace == SPACE_BASE && (i.tm.base_opcode & ~3) == MOV_AX_DISP32) { - default_seg = &ds; + default_seg = reg_ds; } else if (i.tm.opcode_modifier.isstring) { /* For the string instructions that allow a segment override on one of their operands, the default segment is ds. */ - default_seg = &ds; + default_seg = reg_ds; } else if (i.short_form) { @@ -7789,9 +7801,9 @@ process_operands (void) point, and the specified segment prefix will always be used. */ if (i.seg[0] && i.seg[0] != default_seg - && i.seg[0]->seg_prefix != i.prefix[SEG_PREFIX]) + && i386_seg_prefixes[i.seg[0]->reg_num] != i.prefix[SEG_PREFIX]) { - if (!add_prefix (i.seg[0]->seg_prefix)) + if (!add_prefix (i386_seg_prefixes[i.seg[0]->reg_num])) return 0; } return 1; @@ -7816,10 +7828,10 @@ static INLINE void set_rex_vrex (const reg_entry *r, unsigned int rex_bit, i.vrex |= rex_bit; } -static const seg_entry * +static const reg_entry * build_modrm_byte (void) { - const seg_entry *default_seg = 0; + const reg_entry *default_seg = NULL; unsigned int source, dest; int vex_3_sources; @@ -8103,7 +8115,7 @@ build_modrm_byte (void) } } - default_seg = &ds; + default_seg = reg_ds; if (i.base_reg == 0) { @@ -8197,7 +8209,7 @@ build_modrm_byte (void) i.rm.regmem = i.index_reg->reg_num - 6; break; case 5: /* (%bp) */ - default_seg = &ss; + default_seg = reg_ss; if (i.index_reg == 0) { i.rm.regmem = 6; @@ -8258,7 +8270,7 @@ build_modrm_byte (void) if (!(i.base_reg->reg_flags & RegRex) && (i.base_reg->reg_num == EBP_REG_NUM || i.base_reg->reg_num == ESP_REG_NUM)) - default_seg = &ss; + default_seg = reg_ss; if (i.base_reg->reg_num == 5 && i.disp_operands == 0) { fake_zero_displacement = 1; @@ -11325,27 +11337,7 @@ i386_att_operand (char *operand_string) ++op_string; if (*op_string == ':' && r->reg_type.bitfield.class == SReg) { - switch (r->reg_num) - { - case 0: - i.seg[i.mem_operands] = &es; - break; - case 1: - i.seg[i.mem_operands] = &cs; - break; - case 2: - i.seg[i.mem_operands] = &ss; - break; - case 3: - i.seg[i.mem_operands] = &ds; - break; - case 4: - i.seg[i.mem_operands] = &fs; - break; - case 5: - i.seg[i.mem_operands] = &gs; - break; - } + i.seg[i.mem_operands] = r; /* Skip the ':' and whitespace. */ ++op_string; diff --git a/opcodes/ChangeLog b/opcodes/ChangeLog index fb5b8c75ecf..7179187f7d0 100644 --- a/opcodes/ChangeLog +++ b/opcodes/ChangeLog @@ -1,3 +1,10 @@ +2021-03-30 Jan Beulich + + * i386-opc.c (cs, ds, ss, es, fs, gs): Delete. + (i386_seg_prefixes): New. + * i386-opc.h (cs, ds, ss, es, fs, gs): Delete. + (i386_seg_prefixes): Declare. + 2021-03-30 Jan Beulich * i386-opc.h (REGNAM_AL, REGNAM_AX, REGNAM_EAX): Delete. diff --git a/opcodes/i386-opc.c b/opcodes/i386-opc.c index 370adc3a87d..ca3bdfb449b 100644 --- a/opcodes/i386-opc.c +++ b/opcodes/i386-opc.c @@ -23,10 +23,12 @@ #include "i386-opc.h" #include "i386-tbl.h" -/* Segment stuff. */ -const seg_entry cs = { "cs", 0x2e }; -const seg_entry ds = { "ds", 0x3e }; -const seg_entry ss = { "ss", 0x36 }; -const seg_entry es = { "es", 0x26 }; -const seg_entry fs = { "fs", 0x64 }; -const seg_entry gs = { "gs", 0x65 }; +/* To be indexed by segment register number. */ +const unsigned char i386_seg_prefixes[] = { + ES_PREFIX_OPCODE, + CS_PREFIX_OPCODE, + SS_PREFIX_OPCODE, + DS_PREFIX_OPCODE, + FS_PREFIX_OPCODE, + GS_PREFIX_OPCODE +}; diff --git a/opcodes/i386-opc.h b/opcodes/i386-opc.h index 9c451defc93..60c445f2b40 100644 --- a/opcodes/i386-opc.h +++ b/opcodes/i386-opc.h @@ -992,17 +992,4 @@ reg_entry; extern const reg_entry i386_regtab[]; extern const unsigned int i386_regtab_size; - -typedef struct -{ - char *seg_name; - unsigned int seg_prefix; -} -seg_entry; - -extern const seg_entry cs; -extern const seg_entry ds; -extern const seg_entry ss; -extern const seg_entry es; -extern const seg_entry fs; -extern const seg_entry gs; +extern const unsigned char i386_seg_prefixes[6]; -- 2.30.2