Re: [Patch] Bfin: Ensure rotrsi and rotlsi don't accept non-const INTVALS

[Bernd Schmidt]

On 03/31/2011 05:42 PM, Richard Henderson wrote:
>>      (rotate:SI (match_operand:SI 1 "register_operand" "")
>> -               (match_operand:SI 2 "immediate_operand" "")))]
>> +               (match_operand:SI 2 "const_int_operand" "")))]
>>    ""
>>  {
>> -  if (INTVAL (operands[2]) != 16)
>> +  if (GET_CODE (operands[2]) != CONST_INT || INTVAL (operands[2]) != 16)
>>      FAIL;
> 
> The point was, that you'd not need the CONST_INT check anymore,
> because it's handled by the predicate.

I have a dim memory of the problem being that something didn't check the
predicate. Sure enough, with the patch below applied to a 4.3 tree, I get

/local/src/egcs/gcc-4_3-branch/gcc/testsuite/gcc.c-torture/execute/20020226-1.c:43:
internal compiler error: in gen_rotrsi3, at config/bfin/bfin.md:1632
Please submit a full bug report,
with preprocessed source if appropriate.
See <http://gcc.gnu.org/bugs.html> for instructions.
compiler exited with status 1
output is:
(reg:SI 193)

Stuart, try to identify whether it still happens. If so, a better fix
would be to change the expanders to honour the predicate.


Bernd

Index: ../gcc-4_3-branch/gcc/config/bfin/bfin.md
===================================================================
--- ../gcc-4_3-branch/gcc/config/bfin/bfin.md   (revision 147761)
+++ ../gcc-4_3-branch/gcc/config/bfin/bfin.md   (working copy)
@@ -1611,6 +1611,11 @@ (define_expand "rotlsi3"
                   (match_operand:SI 2 "immediate_operand" "")))]
   ""
 {
+  if (GET_CODE (operands[2]) != CONST_INT)
+    {
+      debug_rtx (operands[2]);
+      abort ();
+    }
   if (INTVAL (operands[2]) != 16)
     FAIL;
 })
@@ -1621,6 +1626,11 @@ (define_expand "rotrsi3"
                     (match_operand:SI 2 "immediate_operand" "")))]
   ""
 {
+  if (GET_CODE (operands[2]) != CONST_INT)
+    {
+      debug_rtx (operands[2]);
+      abort ();
+    }
   if (INTVAL (operands[2]) != 16)
     FAIL;
   emit_insn (gen_rotl16 (operands[0], operands[1]));