[binutils-gdb] x86: rework of match_template()'s suffix checking

[binutils-gdb] x86: rework of match_template()'s suffix checking

[Jan Beulich]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=7505bb034c7c8a3d9ecf34e22777114c8bc4a93e

commit 7505bb034c7c8a3d9ecf34e22777114c8bc4a93e
Author: Jan Beulich <jbeulich@suse.com>
Date:   Thu Dec 1 10:00:26 2022 +0100

    x86: rework of match_template()'s suffix checking
    
    (Ab)using i386_opcode_modifier for this has been overkill, as the logic
    doesn't really require the full structure. With the removal of
    LONG_DOUBLE_MNEM_SUFFIX and No_ldSuf there's no good reason at all
    anymore to pull out such a loop invariant: We're dealing a check of a
    bit in the loop for a simple comparison. Do the original compares inside
    the loop, thus also making it easier to understand what is actually
    being checked.

Diff:
---
 gas/config/tc-i386.c | 32 +++++---------------------------
 1 file changed, 5 insertions(+), 27 deletions(-)

diff --git a/gas/config/tc-i386.c b/gas/config/tc-i386.c
index 1c68bc043af..55e2d85d04b 100644
--- a/gas/config/tc-i386.c
+++ b/gas/config/tc-i386.c
@@ -6461,7 +6461,6 @@ match_template (char mnem_suffix)
   i386_operand_type overlap0, overlap1, overlap2, overlap3;
   i386_operand_type overlap4;
   unsigned int found_reverse_match;
-  i386_opcode_modifier suffix_check;
   i386_operand_type operand_types [MAX_OPERANDS];
   int addr_prefix_disp;
   unsigned int j, size_match, check_register, errline = __LINE__;
@@ -6475,27 +6474,6 @@ match_template (char mnem_suffix)
   found_reverse_match = 0;
   addr_prefix_disp = -1;
 
-  /* Prepare for mnemonic suffix check.  */
-  memset (&suffix_check, 0, sizeof (suffix_check));
-  switch (mnem_suffix)
-    {
-    case BYTE_MNEM_SUFFIX:
-      suffix_check.no_bsuf = 1;
-      break;
-    case WORD_MNEM_SUFFIX:
-      suffix_check.no_wsuf = 1;
-      break;
-    case SHORT_MNEM_SUFFIX:
-      suffix_check.no_ssuf = 1;
-      break;
-    case LONG_MNEM_SUFFIX:
-      suffix_check.no_lsuf = 1;
-      break;
-    case QWORD_MNEM_SUFFIX:
-      suffix_check.no_qsuf = 1;
-      break;
-    }
-
   for (t = current_templates->start; t < current_templates->end; t++)
     {
       addr_prefix_disp = -1;
@@ -6543,11 +6521,11 @@ match_template (char mnem_suffix)
 
       /* Check the suffix.  */
       specific_error = progress (invalid_instruction_suffix);
-      if ((t->opcode_modifier.no_bsuf && suffix_check.no_bsuf)
-	  || (t->opcode_modifier.no_wsuf && suffix_check.no_wsuf)
-	  || (t->opcode_modifier.no_lsuf && suffix_check.no_lsuf)
-	  || (t->opcode_modifier.no_ssuf && suffix_check.no_ssuf)
-	  || (t->opcode_modifier.no_qsuf && suffix_check.no_qsuf))
+      if ((t->opcode_modifier.no_bsuf && mnem_suffix == BYTE_MNEM_SUFFIX)
+	  || (t->opcode_modifier.no_wsuf && mnem_suffix == WORD_MNEM_SUFFIX)
+	  || (t->opcode_modifier.no_lsuf && mnem_suffix == LONG_MNEM_SUFFIX)
+	  || (t->opcode_modifier.no_ssuf && mnem_suffix == SHORT_MNEM_SUFFIX)
+	  || (t->opcode_modifier.no_qsuf && mnem_suffix == QWORD_MNEM_SUFFIX))
 	continue;
 
       specific_error = progress (operand_size_mismatch);