x86: adjust st(<N>) parsing

st(1) ... st(7) will never be looked up in the hash table, so there's no
point inserting the entries. It's also not really necessary to do a 2nd
hash lookup after parsing the register number, nor is there a real
reason for having both st and st(0) entries. Plus we can easily do away
with the need for st to be first in the table.

diff --git a/gas/ChangeLog b/gas/ChangeLog
index 8bdc39204898137048add952ebc200bbd8110631..468be74256c76da7dc76a290b30a88bafed2fb7b 100644 (file)
--- a/gas/ChangeLog
+++ b/gas/ChangeLog
@@ -1,3 +1,10 @@
+2021-03-30  Jan Beulich  <jbeulich@suse.com>
+
+       * config/tc-i386.c (reg_st0): New.
+       (md_begin): Convert to switch(). Initialize reg_st0. Don't
+       insert other st(N).
+       (parse_real_register): Adjust st(N) processing.
+
 2021-03-30  Jan Beulich  <jbeulich@suse.com>
 
        * config/tc-i386.c (rc_op): Delete.

diff --git a/gas/config/tc-i386.c b/gas/config/tc-i386.c
index ba130138531e080e9ab56b5853cf15472885cf86..3a7d50484ff49b8bda3c69eb2407af8971f431e1 100644 (file)
--- a/gas/config/tc-i386.c
+++ b/gas/config/tc-i386.c
@@ -214,6 +214,7 @@ static const char *default_arch = DEFAULT_ARCH;
 static const reg_entry bad_reg = { "<bad>", OPERAND_TYPE_NONE, 0, 0,
                                   { Dw2Inval, Dw2Inval } };
 
+static const reg_entry *reg_st0;
 static const reg_entry *reg_k0;
 
 /* VEX prefix.  */
@@ -3087,11 +3088,27 @@ md_begin (void)
 
     for (regtab = i386_regtab; regtab_size--; regtab++)
       {
+       switch (regtab->reg_type.bitfield.class)
+         {
+         case Reg:
+           if (regtab->reg_type.bitfield.tbyte)
+             {
+               /* There's no point inserting st(<N>) in the hash table, as
+                  parentheses aren't included in register_chars[] anyway.  */
+               if (regtab->reg_type.bitfield.instance != Accum)
+                 continue;
+               reg_st0 = regtab;
+             }
+           break;
+
+         case RegMask:
+           if (!regtab->reg_num)
+             reg_k0 = regtab;
+           break;
+         }
+
        if (str_hash_insert (reg_hash, regtab->reg_name, regtab, 0) != NULL)
          as_fatal (_("duplicate %s"), regtab->reg_name);
-
-       if (regtab->reg_type.bitfield.class == RegMask && !regtab->reg_num)
-         reg_k0 = regtab;
       }
   }
 
@@ -12712,7 +12729,7 @@ parse_real_register (char *reg_string, char **end_op)
   r = (const reg_entry *) str_hash_find (reg_hash, reg_name_given);
 
   /* Handle floating point regs, allowing spaces in the (i) part.  */
-  if (r == i386_regtab /* %st is first entry of table  */)
+  if (r == reg_st0)
     {
       if (!cpu_arch_flags.bitfield.cpu8087
          && !cpu_arch_flags.bitfield.cpu287
@@ -12736,8 +12753,7 @@ parse_real_register (char *reg_string, char **end_op)
              if (*s == ')')
                {
                  *end_op = s + 1;
-                 r = (const reg_entry *) str_hash_find (reg_hash, "st(0)");
-                 know (r);
+                 know (r[fpr].reg_num == fpr);
                  return r + fpr;
                }
            }

diff --git a/opcodes/ChangeLog b/opcodes/ChangeLog
index 81c0fa2e7f3d2647f96f5aaf51ca4118bbdcee87..5acb021fa48f8026ce7ba46a590ac418d3c5daad 100644 (file)
--- a/opcodes/ChangeLog
+++ b/opcodes/ChangeLog
@@ -1,3 +1,10 @@
+2021-03-30  Jan Beulich  <jbeulich@suse.com>
+
+       * i386-opc.h (REGNAM_AL, REGNAM_AX, REGNAM_EAX): Adjust values.
+       * i386-reg.tbl (st): Move down.
+       (st(0)): Delete. Extend comment.
+       * i386-tbl.h: Re-generate.
+
 2021-03-29  Jan Beulich  <jbeulich@suse.com>
 
        * i386-opc.tbl (movq, movabs): Move next to mov counterparts.

diff --git a/opcodes/i386-opc.h b/opcodes/i386-opc.h
index 115895c65ed0cb5ba8b59569109611ffb69e0c87..a2a657eeda0e34498efd264496f65e501fb4661e 100644 (file)
--- a/opcodes/i386-opc.h
+++ b/opcodes/i386-opc.h
@@ -991,9 +991,9 @@ typedef struct
 reg_entry;
 
 /* Entries in i386_regtab.  */
-#define REGNAM_AL 1
-#define REGNAM_AX 25
-#define REGNAM_EAX 41
+#define REGNAM_AL 0
+#define REGNAM_AX 24
+#define REGNAM_EAX 40
 
 extern const reg_entry i386_regtab[];
 extern const unsigned int i386_regtab_size;

diff --git a/opcodes/i386-reg.tbl b/opcodes/i386-reg.tbl
index 7ea974de66531f80d0ba9777721a5a76ad589a60..be2c1ccc9f2992a0ee4210924831ef526eef98af 100644 (file)
--- a/opcodes/i386-reg.tbl
+++ b/opcodes/i386-reg.tbl
@@ -18,8 +18,6 @@
 // Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA
 // 02110-1301, USA.
 
-// Make %st first as we test for it.
-st, Class=Reg|Instance=Accum|Tbyte, 0, 0, 11, 33
 // 8 bit regs
 al, Class=Reg|Instance=Accum|Byte, 0, 0, Dw2Inval, Dw2Inval
 cl, Class=Reg|Instance=RegC|Byte, 0, 1, Dw2Inval, Dw2Inval
@@ -300,8 +298,8 @@ eip, Dword, RegRex64, RegIP, 8, Dw2Inval
 // for addressing.
 riz, Qword|BaseIndex, RegRex64, RegIZ, Dw2Inval, Dw2Inval
 eiz, Dword|BaseIndex, 0, RegIZ, Dw2Inval, Dw2Inval
-// fp regs.
-st(0), Class=Reg|Instance=Accum|Tbyte, 0, 0, 11, 33
+// fp regs. No need for an explicit st(0) here.
+st, Class=Reg|Instance=Accum|Tbyte, 0, 0, 11, 33
 st(1), Class=Reg|Tbyte, 0, 1, 12, 34
 st(2), Class=Reg|Tbyte, 0, 2, 13, 35
 st(3), Class=Reg|Tbyte, 0, 3, 14, 36

diff --git a/opcodes/i386-tbl.h b/opcodes/i386-tbl.h
index 0a326fd87861d00f69ab3f20370d43a28bc43f67..d2ca247f028ba24b5af79d6e489b091f7f215485 100644 (file)
--- a/opcodes/i386-tbl.h
+++ b/opcodes/i386-tbl.h
@@ -64204,10 +64204,6 @@ const insn_template i386_optab[] =
 
 const reg_entry i386_regtab[] =
 {
-  { "st",
-    { { 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
-       1, 0, 0, 0, 0, 0, 0 } },
-    0, 0, { 11, 33 } },
   { "al",
     { { 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0,
        0, 0, 0, 0, 0, 0, 0 } },
@@ -65260,7 +65256,7 @@ const reg_entry i386_regtab[] =
     { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 1, 0, 0,
        0, 0, 0, 0, 0, 0, 0 } },
     0, RegIZ, { Dw2Inval, Dw2Inval } },
-  { "st(0)",
+  { "st",
     { { 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
        1, 0, 0, 0, 0, 0, 0 } },
     0, 0, { 11, 33 } },