[binutils-gdb] gas: sparc: allow ASR registers in the 0..31 range in V9 and later

[Jose E.Marchesi <jemarch at sourceware dot org>]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=f65c3d1b26e05f445d976aabd48d4b1264c182bc

commit f65c3d1b26e05f445d976aabd48d4b1264c182bc
Author: Jose E. Marchesi <jose.marchesi@oracle.com>
Date:   Thu Mar 24 10:28:41 2016 -0700

    gas: sparc: allow ASR registers in the 0..31 range in V9 and later
    
    In the SPARC V9 (and later) versions of the SPARC specification, the
    section C.1.1 "Register Names" specifies that:
    
    "asr_reg.  An asr_reg is an Ancillary State Register name.  It may have
     one of the following values:
    
      %asr16-%asr31"
    
    The rationale of having this restriction was that the registers from 16
    to 31 are reserved to implementations, and are therefore "non-V9".  It
    also assumes that the existing ASR registers in the range 0..31 will
    have their own names such as %y, that can be used to access such
    registers.
    
    However, this is problematic.  When a new ASR register is introduced,
    such as %mcdper a.k.a. %asr14, it is useful to be able to use %asr14 in
    order to not depend on the latest version of the assembler.
    
    The Solaris assembler is lax and allows to assembly instructions
    referring to %asr0 to %asr31.  This patch makes the GNU assembler to
    mimic that behavior.
    
    gas/ChangeLog:
    
      2016-03-24  Jose E. Marchesi  <jose.marchesi@oracle.com>
    
    	* config/tc-sparc.c (sparc_ip): Remove the V9 restriction on ASR
    	registers to be in the 16..31 range.

Diff:
---
 gas/ChangeLog         |  5 +++++
 gas/config/tc-sparc.c | 32 ++++++++++++++++----------------
 2 files changed, 21 insertions(+), 16 deletions(-)

diff --git a/gas/ChangeLog b/gas/ChangeLog
index f1f588e..493d779 100644
--- a/gas/ChangeLog
+++ b/gas/ChangeLog
@@ -1,3 +1,8 @@
+2016-03-24  Jose E. Marchesi  <jose.marchesi@oracle.com>
+
+	* config/tc-sparc.c (sparc_ip): Remove the V9 restriction on ASR
+	registers to be in the 16..31 range.
+
 2016-03-24  Trevor Saunders  <tbsaunde+binutils@tbsaunde.org>
 
 	* config/tc-microblaze.c (md_assemble): Cast opc to char * when calling
diff --git a/gas/config/tc-sparc.c b/gas/config/tc-sparc.c
index 5d4e0d6..dfb84ef 100644
--- a/gas/config/tc-sparc.c
+++ b/gas/config/tc-sparc.c
@@ -1841,22 +1841,22 @@ sparc_ip (char *str, const struct sparc_opcode **pinsn)
 			  ++s;
 			}
 
-		      if (current_architecture >= SPARC_OPCODE_ARCH_V9)
-			{
-			  if (num < 16 || 31 < num)
-			    {
-			      error_message = _(": asr number must be between 16 and 31");
-			      goto error;
-			    }
-			}
-		      else
-			{
-			  if (num < 0 || 31 < num)
-			    {
-			      error_message = _(": asr number must be between 0 and 31");
-			      goto error;
-			    }
-			}
+                      /* We used to check here for the asr number to
+                         be between 16 and 31 in V9 and later, as
+                         mandated by the section C.1.1 "Register
+                         Names" in the SPARC spec.  However, we
+                         decided to remove this restriction as a) it
+                         introduces problems when new V9 asr registers
+                         are introduced, b) the Solaris assembler
+                         doesn't implement this restriction and c) the
+                         restriction will go away in future revisions
+                         of the Oracle SPARC Architecture.  */
+
+                      if (num < 0 || 31 < num)
+                        {
+                          error_message = _(": asr number must be between 0 and 31");
+                          goto error;
+                        }
 
 		      opcode |= (*args == 'M' ? RS1 (num) : RD (num));
 		      continue;