[PATCH] x86: prefer specific error messages over more generic ones

["Jan Beulich" <JBeulich at suse dot com>]

At the point where check_VecOperands()/VEX_check_operands() get run,
all other instruction attributes already matched, so any mismatch here
will tell the user more precisely what is wrong than using an eventual
(and very likely to occur) more generic error encountered on a
subsequent iteration through the template matching loop.

2012-07-24  Jan Beulich <jbeulich@suse.com>

	* config/tc-i386.c (match_template): New local variable
	'specific_error'. Set it from i.error after failed
	check_VecOperands or VEX_check_operands. Use it if set in
	preference to i.error when actually issuing disagnostic.

--- a/gas/config/tc-i386.c
+++ b/gas/config/tc-i386.c
@@ -4015,6 +4015,7 @@ match_template (void)
   unsigned int j;
   unsigned int found_cpu_match;
   unsigned int check_register;
+  enum i386_error specific_error = 0;
 
 #if MAX_OPERANDS != 5
 # error "MAX_OPERANDS must be 5."
@@ -4311,13 +4312,12 @@ check_reverse:
 	  continue;
 	}
 
-      /* Check if vector operands are valid.  */
-      if (check_VecOperands (t))
-	continue;
-
-      /* Check if VEX operands are valid.  */
-      if (VEX_check_operands (t))
-	continue;
+      /* Check if vector and VEX operands are valid.  */
+      if (check_VecOperands (t) || VEX_check_operands (t))
+	{
+	  specific_error = i.error;
+	  continue;
+	}
 
       /* We've found a match; break out of loop.  */
       break;
@@ -4327,7 +4327,7 @@ check_reverse:
     {
       /* We found no match.  */
       const char *err_msg;
-      switch (i.error)
+      switch (specific_error ? specific_error : i.error)
 	{
 	default:
 	  abort ();

Attachment: binutils-mainline-x86-specific-error.patch
Description: Text document