public inbox for binutils-cvs@sourceware.org
 help / color / mirror / Atom feed
* [binutils-gdb] x86: use fixed-width type for codep and friends
@ 2023-05-26  7:53 Jan Beulich
  0 siblings, 0 replies; only message in thread
From: Jan Beulich @ 2023-05-26  7:53 UTC (permalink / raw)
  To: bfd-cvs

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=a4aa034a0abca9c93910c23fbe7ed5f07b4c4b0b

commit a4aa034a0abca9c93910c23fbe7ed5f07b4c4b0b
Author: Jan Beulich <jbeulich@suse.com>
Date:   Fri May 26 09:53:01 2023 +0200

    x86: use fixed-width type for codep and friends
    
    This first of all removes a dependency on bfd_byte and unsigned char
    being the same types. It further eliminates the need to mask by 0xff
    when fetching values (which wasn't done fully consistently anyway),
    improving code legibility.
    
    While there, where possible add const.

Diff:
---
 opcodes/i386-dis.c | 112 ++++++++++++++++++++++++++---------------------------
 1 file changed, 55 insertions(+), 57 deletions(-)

diff --git a/opcodes/i386-dis.c b/opcodes/i386-dis.c
index 07fcf3269f9..398be8b20c5 100644
--- a/opcodes/i386-dis.c
+++ b/opcodes/i386-dis.c
@@ -120,8 +120,8 @@ static void ATTRIBUTE_PRINTF_3 i386_dis_printf (const disassemble_info *,
 
 struct dis_private {
   /* Points to first byte not fetched.  */
-  bfd_byte *max_fetched;
-  bfd_byte the_buffer[MAX_MNEM_SIZE];
+  uint8_t *max_fetched;
+  uint8_t the_buffer[MAX_MNEM_SIZE];
   bfd_vma insn_start;
   int orig_sizeflag;
 };
@@ -133,7 +133,7 @@ enum address_mode
   mode_64bit
 };
 
-static const char *prefix_name (enum address_mode, int, int);
+static const char *prefix_name (enum address_mode, uint8_t, int);
 
 enum x86_64_isa
 {
@@ -149,9 +149,9 @@ struct instr_info
   int prefixes;
 
   /* REX prefix the current instruction.  See below.  */
-  unsigned char rex;
+  uint8_t rex;
   /* Bits of REX we've already used.  */
-  unsigned char rex_used;
+  uint8_t rex_used;
 
   bool need_modrm;
   bool need_vex;
@@ -168,10 +168,10 @@ struct instr_info
   char obuf[MAX_OPERAND_BUFFER_SIZE];
   char *obufp;
   char *mnemonicendp;
-  unsigned char *start_codep;
-  unsigned char *insn_codep;
-  unsigned char *codep;
-  unsigned char *end_codep;
+  const uint8_t *start_codep;
+  uint8_t *insn_codep;
+  uint8_t *codep;
+  const uint8_t *end_codep;
   signed char last_lock_prefix;
   signed char last_repz_prefix;
   signed char last_repnz_prefix;
@@ -186,7 +186,7 @@ struct instr_info
 #define MAX_CODE_LENGTH 15
   /* We can up to 14 ins->prefixes since the maximum instruction length is
      15bytes.  */
-  unsigned char all_prefixes[MAX_CODE_LENGTH - 1];
+  uint8_t all_prefixes[MAX_CODE_LENGTH - 1];
   disassemble_info *info;
 
   struct
@@ -288,7 +288,7 @@ struct instr_info
    to ADDR (exclusive) are valid.  Returns true for success, false
    on error.  */
 static bool
-fetch_code (struct disassemble_info *info, bfd_byte *until)
+fetch_code (struct disassemble_info *info, uint8_t *until)
 {
   int status = -1;
   struct dis_private *priv = info->private_data;
@@ -8833,7 +8833,8 @@ static enum {
 }
 ckprefix (instr_info *ins)
 {
-  int newrex, i, length;
+  int i, length;
+  uint8_t newrex;
 
   i = 0;
   length = 0;
@@ -8843,7 +8844,7 @@ ckprefix (instr_info *ins)
       if (!fetch_code (ins->info, ins->codep + 1))
 	return ckp_fetch_error;
       newrex = 0;
-      switch (*ins->codep & 0xff)
+      switch (*ins->codep)
 	{
 	/* REX prefixes family.  */
 	case 0x40:
@@ -8863,7 +8864,7 @@ ckprefix (instr_info *ins)
 	case 0x4e:
 	case 0x4f:
 	  if (ins->address_mode == mode_64bit)
-	    newrex = *ins->codep & 0xff;
+	    newrex = *ins->codep;
 	  else
 	    return ckp_okay;
 	  ins->last_rex_prefix = i;
@@ -8943,8 +8944,8 @@ ckprefix (instr_info *ins)
       /* Rex is ignored when followed by another prefix.  */
       if (ins->rex)
 	return ckp_bogus;
-      if ((*ins->codep & 0xff) != FWAIT_OPCODE)
-	ins->all_prefixes[i++] = *ins->codep & 0xff;
+      if (*ins->codep != FWAIT_OPCODE)
+	ins->all_prefixes[i++] = *ins->codep;
       ins->rex = newrex;
       ins->codep++;
       length++;
@@ -8956,7 +8957,7 @@ ckprefix (instr_info *ins)
    prefix byte.  */
 
 static const char *
-prefix_name (enum address_mode mode, int pref, int sizeflag)
+prefix_name (enum address_mode mode, uint8_t pref, int sizeflag)
 {
   static const char *rexes [16] =
     {
@@ -9175,7 +9176,7 @@ get_valid_dis386 (const struct dis386 *dp, instr_info *ins)
     case USE_3BYTE_TABLE:
       if (!fetch_code (ins->info, ins->codep + 2))
 	return &err_opcode;
-      vindex = *ins->codep++ & 0xff;
+      vindex = *ins->codep++;
       dp = &three_byte_table[dp->op[1].bytemode][vindex];
       ins->end_codep = ins->codep;
       if (!fetch_modrm (ins))
@@ -9282,7 +9283,7 @@ get_valid_dis386 (const struct dis386 *dp, instr_info *ins)
 	}
       ins->need_vex = true;
       ins->codep++;
-      vindex = *ins->codep++ & 0xff;
+      vindex = *ins->codep++;
       dp = &xop_table[vex_table_index][vindex];
 
       ins->end_codep = ins->codep;
@@ -9347,7 +9348,7 @@ get_valid_dis386 (const struct dis386 *dp, instr_info *ins)
 	}
       ins->need_vex = true;
       ins->codep++;
-      vindex = *ins->codep++ & 0xff;
+      vindex = *ins->codep++;
       dp = &vex_table[vex_table_index][vindex];
       ins->end_codep = ins->codep;
       /* There is no MODRM byte for VEX0F 77.  */
@@ -9382,7 +9383,7 @@ get_valid_dis386 (const struct dis386 *dp, instr_info *ins)
 	}
       ins->need_vex = true;
       ins->codep++;
-      vindex = *ins->codep++ & 0xff;
+      vindex = *ins->codep++;
       dp = &vex_table[dp->op[1].bytemode][vindex];
       ins->end_codep = ins->codep;
       /* There is no MODRM byte for VEX 77.  */
@@ -9474,7 +9475,7 @@ get_valid_dis386 (const struct dis386 *dp, instr_info *ins)
 
       ins->need_vex = true;
       ins->codep++;
-      vindex = *ins->codep++ & 0xff;
+      vindex = *ins->codep++;
       dp = &evex_table[vex_table_index][vindex];
       ins->end_codep = ins->codep;
       if (!fetch_modrm (ins))
@@ -9821,11 +9822,10 @@ print_insn (bfd_vma pc, disassemble_info *info, int intel_syntax)
       goto out;
     }
 
-  ins.two_source_ops = ((*ins.codep & 0xff) == 0x62
-			|| (*ins.codep & 0xff) == 0xc8);
+  ins.two_source_ops = (*ins.codep == 0x62 || *ins.codep == 0xc8);
 
   if ((ins.prefixes & PREFIX_FWAIT)
-      && ((*ins.codep & 0xff) < 0xd8 || (*ins.codep & 0xff) > 0xdf))
+      && (*ins.codep < 0xd8 || *ins.codep > 0xdf))
     {
       /* Handle ins.prefixes before fwait.  */
       for (i = 0; i < ins.fwait_prefix && ins.all_prefixes[i];
@@ -9838,22 +9838,22 @@ print_insn (bfd_vma pc, disassemble_info *info, int intel_syntax)
       goto out;
     }
 
-  if ((*ins.codep & 0xff) == 0x0f)
+  if (*ins.codep == 0x0f)
     {
       unsigned char threebyte;
 
       ins.codep++;
       if (!fetch_code (info, ins.codep + 1))
 	goto fetch_error_out;
-      threebyte = *ins.codep & 0xff;
+      threebyte = *ins.codep;
       dp = &dis386_twobyte[threebyte];
       ins.need_modrm = twobyte_has_modrm[threebyte];
       ins.codep++;
     }
   else
     {
-      dp = &dis386[*ins.codep & 0xff];
-      ins.need_modrm = onebyte_has_modrm[*ins.codep & 0xff];
+      dp = &dis386[*ins.codep];
+      ins.need_modrm = onebyte_has_modrm[*ins.codep];
       ins.codep++;
     }
 
@@ -10553,9 +10553,7 @@ static bool
 dofloat (instr_info *ins, int sizeflag)
 {
   const struct dis386 *dp;
-  unsigned char floatop;
-
-  floatop = ins->codep[-1] & 0xff;
+  unsigned char floatop = ins->codep[-1];
 
   if (ins->modrm.mod != 3)
     {
@@ -10576,7 +10574,7 @@ dofloat (instr_info *ins, int sizeflag)
       putop (ins, fgrps[dp->op[0].bytemode][ins->modrm.rm], sizeflag);
 
       /* Instruction fnstsw is only one with strange arg.  */
-      if (floatop == 0xdf && (ins->codep[-1] & 0xff) == 0xe0)
+      if (floatop == 0xdf && ins->codep[-1] == 0xe0)
 	strcpy (ins->op_out[0], att_names16[0] + ins->intel_syntax);
     }
   else
@@ -11749,7 +11747,7 @@ get8s (instr_info *ins, bfd_vma *res)
 {
   if (!fetch_code (ins->info, ins->codep + 1))
     return false;
-  *res = (((bfd_vma) *ins->codep++ & 0xff) ^ 0x80) - 0x80;
+  *res = ((bfd_vma) *ins->codep++ ^ 0x80) - 0x80;
   return true;
 }
 
@@ -11758,8 +11756,8 @@ get16 (instr_info *ins, bfd_vma *res)
 {
   if (!fetch_code (ins->info, ins->codep + 2))
     return false;
-  *res = (bfd_vma) *ins->codep++ & 0xff;
-  *res |= ((bfd_vma) *ins->codep++ & 0xff) << 8;
+  *res = *ins->codep++;
+  *res |= (bfd_vma) *ins->codep++ << 8;
   return true;
 }
 
@@ -11777,10 +11775,10 @@ get32 (instr_info *ins, bfd_vma *res)
 {
   if (!fetch_code (ins->info, ins->codep + 4))
     return false;
-  *res = *ins->codep++ & (bfd_vma) 0xff;
-  *res |= (*ins->codep++ & (bfd_vma) 0xff) << 8;
-  *res |= (*ins->codep++ & (bfd_vma) 0xff) << 16;
-  *res |= (*ins->codep++ & (bfd_vma) 0xff) << 24;
+  *res = *ins->codep++;
+  *res |= (bfd_vma) *ins->codep++ << 8;
+  *res |= (bfd_vma) *ins->codep++ << 16;
+  *res |= (bfd_vma) *ins->codep++ << 24;
   return true;
 }
 
@@ -11803,14 +11801,14 @@ get64 (instr_info *ins, uint64_t *res)
 
   if (!fetch_code (ins->info, ins->codep + 8))
     return false;
-  a = *ins->codep++ & 0xff;
-  a |= (*ins->codep++ & 0xff) << 8;
-  a |= (*ins->codep++ & 0xff) << 16;
-  a |= (*ins->codep++ & 0xffu) << 24;
-  b = *ins->codep++ & 0xff;
-  b |= (*ins->codep++ & 0xff) << 8;
-  b |= (*ins->codep++ & 0xff) << 16;
-  b |= (*ins->codep++ & 0xffu) << 24;
+  a = *ins->codep++;
+  a |= (unsigned int) *ins->codep++ << 8;
+  a |= (unsigned int) *ins->codep++ << 16;
+  a |= (unsigned int) *ins->codep++ << 24;
+  b = *ins->codep++;
+  b |= (unsigned int) *ins->codep++ << 8;
+  b |= (unsigned int) *ins->codep++ << 16;
+  b |= (unsigned int) *ins->codep++ << 24;
   *res = a + ((uint64_t) b << 32);
   return true;
 }
@@ -12489,7 +12487,7 @@ OP_I (instr_info *ins, int bytemode, int sizeflag)
     case b_mode:
       if (!fetch_code (ins->info, ins->codep + 1))
 	return false;
-      op = *ins->codep++ & 0xff;
+      op = *ins->codep++;
       break;
     case v_mode:
       USED_REX (REX_W);
@@ -12776,7 +12774,7 @@ OP_ESreg (instr_info *ins, int code, int sizeflag)
 {
   if (ins->intel_syntax)
     {
-      switch (ins->codep[-1] & 0xff)
+      switch (ins->codep[-1])
 	{
 	case 0x6d:	/* insw/insl */
 	  intel_operand_size (ins, z_mode, sizeflag);
@@ -12802,7 +12800,7 @@ OP_DSreg (instr_info *ins, int code, int sizeflag)
 {
   if (ins->intel_syntax)
     {
-      switch (ins->codep[-1] & 0xff)
+      switch (ins->codep[-1])
 	{
 	case 0x6f:	/* outsw/outsl */
 	  intel_operand_size (ins, z_mode, sizeflag);
@@ -13248,7 +13246,7 @@ OP_3DNowSuffix (instr_info *ins, int bytemode ATTRIBUTE_UNUSED,
      place where an 8-bit immediate would normally go.  ie. the last
      byte of the instruction.  */
   ins->obufp = ins->mnemonicendp;
-  mnemonic = Suffix3DNow[*ins->codep++ & 0xff];
+  mnemonic = Suffix3DNow[*ins->codep++];
   if (mnemonic)
     ins->obufp = stpcpy (ins->obufp, mnemonic);
   else
@@ -13313,7 +13311,7 @@ CMP_Fixup (instr_info *ins, int bytemode ATTRIBUTE_UNUSED,
 
   if (!fetch_code (ins->info, ins->codep + 1))
     return false;
-  cmp_type = *ins->codep++ & 0xff;
+  cmp_type = *ins->codep++;
   if (cmp_type < ARRAY_SIZE (simd_cmp_op))
     {
       char suffix[3];
@@ -13763,7 +13761,7 @@ OP_REG_VexI4 (instr_info *ins, int bytemode, int sizeflag ATTRIBUTE_UNUSED)
 
   if (!fetch_code (ins->info, ins->codep + 1))
     return false;
-  reg = *ins->codep++ & 0xff;
+  reg = *ins->codep++;
 
   if (bytemode != x_mode && bytemode != scalar_mode)
     abort ();
@@ -13807,7 +13805,7 @@ VPCMP_Fixup (instr_info *ins, int bytemode ATTRIBUTE_UNUSED,
 
   if (!fetch_code (ins->info, ins->codep + 1))
     return false;
-  cmp_type = *ins->codep++ & 0xff;
+  cmp_type = *ins->codep++;
   /* There are aliases for immediates 0, 1, 2, 4, 5, 6.
      If it's the case, print suffix, otherwise - print the immediate.  */
   if (cmp_type < ARRAY_SIZE (simd_cmp_op)
@@ -13862,7 +13860,7 @@ VPCOM_Fixup (instr_info *ins, int bytemode ATTRIBUTE_UNUSED,
 
   if (!fetch_code (ins->info, ins->codep + 1))
     return false;
-  cmp_type = *ins->codep++ & 0xff;
+  cmp_type = *ins->codep++;
   if (cmp_type < ARRAY_SIZE (xop_cmp_op))
     {
       char suffix[3];
@@ -13909,7 +13907,7 @@ PCLMUL_Fixup (instr_info *ins, int bytemode ATTRIBUTE_UNUSED,
 
   if (!fetch_code (ins->info, ins->codep + 1))
     return false;
-  pclmul_type = *ins->codep++ & 0xff;
+  pclmul_type = *ins->codep++;
   switch (pclmul_type)
     {
     case 0x10:

^ permalink raw reply	[flat|nested] only message in thread

only message in thread, other threads:[~2023-05-26  7:53 UTC | newest]

Thread overview: (only message) (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2023-05-26  7:53 [binutils-gdb] x86: use fixed-width type for codep and friends Jan Beulich

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).