* config/tc-arm.c (warn_deprecated_sp): New macro.

	(do_t_mov_cmp): Permit R13 as the second
	argument to "cmp.n".

	* gas/arm/thumb2_bad_reg.s: Update to allow R13 as second argument
	for CMP.
	* gas/arm/thumb2_bad_reg.l: Adjust accordingly.

5 files changed, 40 insertions, 1 deletions

diff --git a/gas/ChangeLog b/gas/ChangeLog
index 67161df..c1207bd 100644
--- a/gas/ChangeLog
+++ b/gas/ChangeLog
@@ -1,3 +1,9 @@
+2009-02-23  Mark Mitchell  <mark@codesourcery.com>
+
+	* config/tc-arm.c (warn_deprecated_sp): New macro.
+	(do_t_mov_cmp): Permit R13 as the second
+	argument to "cmp.n".
+
 2009-02-23  H.J. Lu  <hongjiu.lu@intel.com>
 
 	* config/tc-i386.c (type_names): Add OPERAND_TYPE_REGYMM.
diff --git a/gas/config/tc-arm.c b/gas/config/tc-arm.c
index 782d10b..a1e5d12 100644
--- a/gas/config/tc-arm.c
+++ b/gas/config/tc-arm.c
@@ -6140,6 +6140,14 @@ parse_operands (char *str, const unsigned char *pattern)
      }							\
   while (0)
 
+/* If REG is R13 (the stack pointer), warn that its use is
+   deprecated.  */
+#define warn_deprecated_sp(reg)			\
+  do						\
+    if (warn_on_deprecated && reg == REG_SP)	\
+       as_warn (_("use of r13 is deprecated"));	\
+  while (0)
+
 /* Functions for operand encoding.  ARM, then Thumb.  */
 
 #define rotate_left(v, n) (v << n | v >> (32 - n))
@@ -9690,7 +9698,18 @@ do_t_mov_cmp (void)
       if (opcode == T_MNEM_cmp)
 	{
 	  constraint (Rn == REG_PC, BAD_PC);
-	  reject_bad_reg (Rm);
+	  if (narrow)
+	    {
+	      /* In the Thumb-2 ISA, use of R13 as Rm is deprecated,
+		 but valid.  */
+	      warn_deprecated_sp (Rm);
+	      /* R15 was documented as a valid choice for Rm in ARMv6,
+		 but as UNPREDICTABLE in ARMv7.  ARM's proprietary
+		 tools reject R15, so we do too.  */
+	      constraint (Rm == REG_PC, BAD_PC);
+	    }
+	  else
+	    reject_bad_reg (Rm);
 	}
       else if (opcode == T_MNEM_mov
 	       || opcode == T_MNEM_movs)
diff --git a/gas/testsuite/ChangeLog b/gas/testsuite/ChangeLog
index 99ea036..b1b23c2 100644
--- a/gas/testsuite/ChangeLog
+++ b/gas/testsuite/ChangeLog
@@ -1,3 +1,9 @@
+2009-02-23  Mark Mitchell  <mark@codesourcery.com>
+
+	* gas/arm/thumb2_bad_reg.s: Update to allow R13 as second argument
+	for CMP.
+	* gas/arm/thumb2_bad_reg.l: Adjust accordingly.
+
 2009-02-19  Peter Bergner  <bergner@vnet.ibm.com>
 
 	* gas/ppc/e500mc.d ("lfdepx", "stfdepx"): Fix tests to expect a
diff --git a/gas/testsuite/gas/arm/thumb2_bad_reg.l b/gas/testsuite/gas/arm/thumb2_bad_reg.l
index 46b4924..f22df10 100644
--- a/gas/testsuite/gas/arm/thumb2_bad_reg.l
+++ b/gas/testsuite/gas/arm/thumb2_bad_reg.l
@@ -76,6 +76,10 @@
 [^:]*:[0-9]+: Error: r15 not allowed here -- `cmn.w r0,r15'
 [^:]*:[0-9]+: Error: r15 not allowed here -- `cmp.w r15,#1'
 [^:]*:[0-9]+: Error: r15 not allowed here -- `cmp r15,r0'
+[^:]*:[0-9]+: Warning: use of r13 is deprecated
+[^:]*:[0-9]+: Error: r15 not allowed here -- `cmp r0,r15'
+[^:]*:[0-9]+: Warning: use of r13 is deprecated
+[^:]*:[0-9]+: Error: r15 not allowed here -- `cmp.n r0,r15'
 [^:]*:[0-9]+: Error: r15 not allowed here -- `cmp.w r15,r0'
 [^:]*:[0-9]+: Error: r13 not allowed here -- `cmp.w r0,r13'
 [^:]*:[0-9]+: Error: r15 not allowed here -- `cmp.w r0,r15'
diff --git a/gas/testsuite/gas/arm/thumb2_bad_reg.s b/gas/testsuite/gas/arm/thumb2_bad_reg.s
index 77134c3..90c82e6 100644
--- a/gas/testsuite/gas/arm/thumb2_bad_reg.s
+++ b/gas/testsuite/gas/arm/thumb2_bad_reg.s
@@ -114,6 +114,10 @@ test:
 	@ CMP (register)
 	cmp r13, r0			@ OK
 	cmp r15, r0
+	cmp r0, r13                     @ Deprecated
+	cmp r0, r15                     
+	cmp.n r0, r13                   @ Deprecated
+	cmp.n r0, r15                   
 	cmp.w r13, r0			@ OK
 	cmp.w r15, r0
 	cmp.w r0, r13