Re: [vec-cmp, patch 1/6] Add optabs for vector comparison

[Jeff Law]

On 11/05/2015 09:01 AM, Ilya Enkovich wrote:

2015-10-27 23:52 GMT+03:00 Jeff Law :


Sigh.  I searched for the enum type, not for CODE_FOR_nothing ;(  My bad.

If it's easy to get rid of, yes.  I believe we've got 3 uses of
CODE_FOR_nothing.  AFAICT in none of those cases do we care about the code
other than does it correspond to CODE_FOR_nothing.

Ideally we'd like to have both optabs-query and optabs-tree not know about
insn codes.  The former is supposed to be IR agnostic, but insn codes are
part of the RTL IR, so that's a wart.  The latter is supposed to be tree
specific and thus shouldn't know about the RTL IR either.

I'd settle for getting the wart out of optabs-tree and we can put further
cleanup of optabs-query in the queue.

To get the wart out of optabs-tree all I think we need is a true boolean
function that tells us if there's a suitable optab.

It's unfortunate that the routines exported by optabs-query are
can_{extend,float,fix}_p since those would fairly natural for the boolean
query we want to make and they're used elsewhere, but not in a boolean form.

I think that we ought to rename the existing uses & definition of can_XXX_p
that are exported by optabs-query.c, then creating new can_XXX_p for those
uses that just care about the boolean status should work.  At that point we
remove insn-codes.h from optab-tree.c.


Do you want this refactoring be a part of this patch or series?
I would have preferred before, but I think we're at a state where doing 
it after makes more sense.  So let's unblock this patch and I'll make an 
exception for the minor refactoring to go in shortly after stage1 closes.


Jeff

Re: [vec-cmp, patch 1/6] Add optabs for vector comparison

[Ilya Enkovich]

2015-10-27 23:52 GMT+03:00 Jeff Law :
>
> Sigh.  I searched for the enum type, not for CODE_FOR_nothing ;(  My bad.
>
> If it's easy to get rid of, yes.  I believe we've got 3 uses of
> CODE_FOR_nothing.  AFAICT in none of those cases do we care about the code
> other than does it correspond to CODE_FOR_nothing.
>
> Ideally we'd like to have both optabs-query and optabs-tree not know about
> insn codes.  The former is supposed to be IR agnostic, but insn codes are
> part of the RTL IR, so that's a wart.  The latter is supposed to be tree
> specific and thus shouldn't know about the RTL IR either.
>
> I'd settle for getting the wart out of optabs-tree and we can put further
> cleanup of optabs-query in the queue.
>
> To get the wart out of optabs-tree all I think we need is a true boolean
> function that tells us if there's a suitable optab.
>
> It's unfortunate that the routines exported by optabs-query are
> can_{extend,float,fix}_p since those would fairly natural for the boolean
> query we want to make and they're used elsewhere, but not in a boolean form.
>
> I think that we ought to rename the existing uses & definition of can_XXX_p
> that are exported by optabs-query.c, then creating new can_XXX_p for those
> uses that just care about the boolean status should work.  At that point we
> remove insn-codes.h from optab-tree.c.

Do you want this refactoring be a part of this patch or series?

Thanks,
Ilya

>
> Jeff

Re: [vec-cmp, patch 1/6] Add optabs for vector comparison

[Jeff Law]

On 10/22/2015 10:12 AM, Ilya Enkovich wrote:

2015-10-22 18:52 GMT+03:00 Jeff Law :

On 10/22/2015 04:35 AM, Ilya Enkovich wrote:


2015-10-21 20:25 GMT+03:00 Jeff Law :


On 10/08/2015 08:52 AM, Ilya Enkovich wrote:



Hi,

This series introduces autogeneration of vector comparison and its
support
on i386 target.  It lets comparison statements to be vectorized into
vector
comparison instead of VEC_COND_EXPR.  This allows to avoid some
restrictions
implied by boolean patterns.  This series applies on top of bolean
vectors
series [1].

This patch introduces optabs for vector comparison.

[1] https://gcc.gnu.org/ml/gcc-patches/2015-10/msg00215.html

Thanks,
Ilya
--
gcc/

2015-10-08  Ilya Enkovich  

  * expr.c (do_store_flag): Use expand_vec_cmp_expr for mask
results.
  * optabs-query.h (get_vec_cmp_icode): New.
  * optabs-tree.c (expand_vec_cmp_expr_p): New.
  * optabs-tree.h (expand_vec_cmp_expr_p): New.
  * optabs.c (vector_compare_rtx): Add OPNO arg.
  (expand_vec_cond_expr): Adjust to vector_compare_rtx change.
  (expand_vec_cmp_expr): New.
  * optabs.def (vec_cmp_optab): New.
  (vec_cmpu_optab): New.
  * optabs.h (expand_vec_cmp_expr): New.
  * tree-vect-generic.c (expand_vector_comparison): Add vector
  comparison optabs check.


diff --git a/gcc/optabs-tree.c b/gcc/optabs-tree.c
index 3b03338..aa863cf 100644
--- a/gcc/optabs-tree.c
+++ b/gcc/optabs-tree.c
@@ -320,6 +320,19 @@ supportable_convert_operation (enum tree_code code,
  return false;
}

+/* Return TRUE if appropriate vector insn is available
+   for vector comparison expr with vector type VALUE_TYPE
+   and resulting mask with MASK_TYPE.  */
+
+bool
+expand_vec_cmp_expr_p (tree value_type, tree mask_type)
+{
+  enum insn_code icode = get_vec_cmp_icode (TYPE_MODE (value_type),
+   TYPE_MODE (mask_type),
+   TYPE_UNSIGNED (value_type));
+  return (icode != CODE_FOR_nothing);
+}
+



Nothing inherently wrong with the code, but it seems like it's in the
wrong
place.  Why optabs-tree rather than optabs-query?



Because it uses tree type for arguments. There is no single tree usage
in optabs-query.c. I think expand_vec_cond_expr_p is in optabs-tree
for the same reason.


Note that expand_vec_cond_expr_p doesn't rely on enum insn code.  Well, it
relies on enum insn code being an integer and CODE_FOR_nothing always having
the value zero, which is probably worse.


Actually it also uses CODE_FOR_nothing in comparison:

   || get_vcond_icode (TYPE_MODE (value_type), TYPE_MODE (cmp_op_type),
   TYPE_UNSIGNED (cmp_op_type)) == CODE_FOR_nothing)

There are also two other instances of CODE_FOR_nothing in
optabs-tree.c. Do you want to get rid of "#include insn-codes.h" in
optabs-tree.c? Will it be really better if we replace it with
"#include optabs-query.h"?

Sigh.  I searched for the enum type, not for CODE_FOR_nothing ;(  My bad.

If it's easy to get rid of, yes.  I believe we've got 3 uses of 
CODE_FOR_nothing.  AFAICT in none of those cases do we care about the 
code other than does it correspond to CODE_FOR_nothing.


Ideally we'd like to have both optabs-query and optabs-tree not know 
about insn codes.  The former is supposed to be IR agnostic, but insn 
codes are part of the RTL IR, so that's a wart.  The latter is supposed 
to be tree specific and thus shouldn't know about the RTL IR either.


I'd settle for getting the wart out of optabs-tree and we can put 
further cleanup of optabs-query in the queue.


To get the wart out of optabs-tree all I think we need is a true boolean 
function that tells us if there's a suitable optab.


It's unfortunate that the routines exported by optabs-query are 
can_{extend,float,fix}_p since those would fairly natural for the 
boolean query we want to make and they're used elsewhere, but not in a 
boolean form.


I think that we ought to rename the existing uses & definition of 
can_XXX_p that are exported by optabs-query.c, then creating new 
can_XXX_p for those uses that just care about the boolean status should 
work.  At that point we remove insn-codes.h from optab-tree.c.


Jeff

Re: [vec-cmp, patch 1/6] Add optabs for vector comparison

[Ilya Enkovich]

2015-10-21 20:25 GMT+03:00 Jeff Law :
> On 10/08/2015 08:52 AM, Ilya Enkovich wrote:
>>
>> Hi,
>>
>> This series introduces autogeneration of vector comparison and its support
>> on i386 target.  It lets comparison statements to be vectorized into vector
>> comparison instead of VEC_COND_EXPR.  This allows to avoid some restrictions
>> implied by boolean patterns.  This series applies on top of bolean vectors
>> series [1].
>>
>> This patch introduces optabs for vector comparison.
>>
>> [1] https://gcc.gnu.org/ml/gcc-patches/2015-10/msg00215.html
>>
>> Thanks,
>> Ilya
>> --
>> gcc/
>>
>> 2015-10-08  Ilya Enkovich  
>>
>> * expr.c (do_store_flag): Use expand_vec_cmp_expr for mask
>> results.
>> * optabs-query.h (get_vec_cmp_icode): New.
>> * optabs-tree.c (expand_vec_cmp_expr_p): New.
>> * optabs-tree.h (expand_vec_cmp_expr_p): New.
>> * optabs.c (vector_compare_rtx): Add OPNO arg.
>> (expand_vec_cond_expr): Adjust to vector_compare_rtx change.
>> (expand_vec_cmp_expr): New.
>> * optabs.def (vec_cmp_optab): New.
>> (vec_cmpu_optab): New.
>> * optabs.h (expand_vec_cmp_expr): New.
>> * tree-vect-generic.c (expand_vector_comparison): Add vector
>> comparison optabs check.
>>
>>
>> diff --git a/gcc/optabs-tree.c b/gcc/optabs-tree.c
>> index 3b03338..aa863cf 100644
>> --- a/gcc/optabs-tree.c
>> +++ b/gcc/optabs-tree.c
>> @@ -320,6 +320,19 @@ supportable_convert_operation (enum tree_code code,
>> return false;
>>   }
>>
>> +/* Return TRUE if appropriate vector insn is available
>> +   for vector comparison expr with vector type VALUE_TYPE
>> +   and resulting mask with MASK_TYPE.  */
>> +
>> +bool
>> +expand_vec_cmp_expr_p (tree value_type, tree mask_type)
>> +{
>> +  enum insn_code icode = get_vec_cmp_icode (TYPE_MODE (value_type),
>> +   TYPE_MODE (mask_type),
>> +   TYPE_UNSIGNED (value_type));
>> +  return (icode != CODE_FOR_nothing);
>> +}
>> +
>
> Nothing inherently wrong with the code, but it seems like it's in the wrong
> place.  Why optabs-tree rather than optabs-query?

Because it uses tree type for arguments. There is no single tree usage
in optabs-query.c. I think expand_vec_cond_expr_p is in optabs-tree
for the same reason.

Thanks,
Ilya

>
> I think with that fixed this patch will be ready to go onto the trunk.
>
> jeff
>

Re: [vec-cmp, patch 1/6] Add optabs for vector comparison

[Jeff Law]

On 10/22/2015 04:35 AM, Ilya Enkovich wrote:

2015-10-21 20:25 GMT+03:00 Jeff Law :

On 10/08/2015 08:52 AM, Ilya Enkovich wrote:


Hi,

This series introduces autogeneration of vector comparison and its support
on i386 target.  It lets comparison statements to be vectorized into vector
comparison instead of VEC_COND_EXPR.  This allows to avoid some restrictions
implied by boolean patterns.  This series applies on top of bolean vectors
series [1].

This patch introduces optabs for vector comparison.

[1] https://gcc.gnu.org/ml/gcc-patches/2015-10/msg00215.html

Thanks,
Ilya
--
gcc/

2015-10-08  Ilya Enkovich  

 * expr.c (do_store_flag): Use expand_vec_cmp_expr for mask
results.
 * optabs-query.h (get_vec_cmp_icode): New.
 * optabs-tree.c (expand_vec_cmp_expr_p): New.
 * optabs-tree.h (expand_vec_cmp_expr_p): New.
 * optabs.c (vector_compare_rtx): Add OPNO arg.
 (expand_vec_cond_expr): Adjust to vector_compare_rtx change.
 (expand_vec_cmp_expr): New.
 * optabs.def (vec_cmp_optab): New.
 (vec_cmpu_optab): New.
 * optabs.h (expand_vec_cmp_expr): New.
 * tree-vect-generic.c (expand_vector_comparison): Add vector
 comparison optabs check.


diff --git a/gcc/optabs-tree.c b/gcc/optabs-tree.c
index 3b03338..aa863cf 100644
--- a/gcc/optabs-tree.c
+++ b/gcc/optabs-tree.c
@@ -320,6 +320,19 @@ supportable_convert_operation (enum tree_code code,
 return false;
   }

+/* Return TRUE if appropriate vector insn is available
+   for vector comparison expr with vector type VALUE_TYPE
+   and resulting mask with MASK_TYPE.  */
+
+bool
+expand_vec_cmp_expr_p (tree value_type, tree mask_type)
+{
+  enum insn_code icode = get_vec_cmp_icode (TYPE_MODE (value_type),
+   TYPE_MODE (mask_type),
+   TYPE_UNSIGNED (value_type));
+  return (icode != CODE_FOR_nothing);
+}
+


Nothing inherently wrong with the code, but it seems like it's in the wrong
place.  Why optabs-tree rather than optabs-query?


Because it uses tree type for arguments. There is no single tree usage
in optabs-query.c. I think expand_vec_cond_expr_p is in optabs-tree
for the same reason.
Note that expand_vec_cond_expr_p doesn't rely on enum insn code.  Well, 
it relies on enum insn code being an integer and CODE_FOR_nothing always 
having the value zero, which is probably worse.


We should clean both of these up so that:

  1. We don't need enum insn_code in optabs-tree
  2. We don't implicitly rely on CODE_FOR_nothing == 0

It may be as simple as a adding a predicate function to optabs-query 
that returns true/false if there's a suitable icode, then using that 
predicate in optabs-tree.


jeff

Re: [vec-cmp, patch 1/6] Add optabs for vector comparison

[Ilya Enkovich]

2015-10-22 18:52 GMT+03:00 Jeff Law :
> On 10/22/2015 04:35 AM, Ilya Enkovich wrote:
>>
>> 2015-10-21 20:25 GMT+03:00 Jeff Law :
>>>
>>> On 10/08/2015 08:52 AM, Ilya Enkovich wrote:


 Hi,

 This series introduces autogeneration of vector comparison and its
 support
 on i386 target.  It lets comparison statements to be vectorized into
 vector
 comparison instead of VEC_COND_EXPR.  This allows to avoid some
 restrictions
 implied by boolean patterns.  This series applies on top of bolean
 vectors
 series [1].

 This patch introduces optabs for vector comparison.

 [1] https://gcc.gnu.org/ml/gcc-patches/2015-10/msg00215.html

 Thanks,
 Ilya
 --
 gcc/

 2015-10-08  Ilya Enkovich  

  * expr.c (do_store_flag): Use expand_vec_cmp_expr for mask
 results.
  * optabs-query.h (get_vec_cmp_icode): New.
  * optabs-tree.c (expand_vec_cmp_expr_p): New.
  * optabs-tree.h (expand_vec_cmp_expr_p): New.
  * optabs.c (vector_compare_rtx): Add OPNO arg.
  (expand_vec_cond_expr): Adjust to vector_compare_rtx change.
  (expand_vec_cmp_expr): New.
  * optabs.def (vec_cmp_optab): New.
  (vec_cmpu_optab): New.
  * optabs.h (expand_vec_cmp_expr): New.
  * tree-vect-generic.c (expand_vector_comparison): Add vector
  comparison optabs check.


 diff --git a/gcc/optabs-tree.c b/gcc/optabs-tree.c
 index 3b03338..aa863cf 100644
 --- a/gcc/optabs-tree.c
 +++ b/gcc/optabs-tree.c
 @@ -320,6 +320,19 @@ supportable_convert_operation (enum tree_code code,
  return false;
}

 +/* Return TRUE if appropriate vector insn is available
 +   for vector comparison expr with vector type VALUE_TYPE
 +   and resulting mask with MASK_TYPE.  */
 +
 +bool
 +expand_vec_cmp_expr_p (tree value_type, tree mask_type)
 +{
 +  enum insn_code icode = get_vec_cmp_icode (TYPE_MODE (value_type),
 +   TYPE_MODE (mask_type),
 +   TYPE_UNSIGNED (value_type));
 +  return (icode != CODE_FOR_nothing);
 +}
 +
>>>
>>>
>>> Nothing inherently wrong with the code, but it seems like it's in the
>>> wrong
>>> place.  Why optabs-tree rather than optabs-query?
>>
>>
>> Because it uses tree type for arguments. There is no single tree usage
>> in optabs-query.c. I think expand_vec_cond_expr_p is in optabs-tree
>> for the same reason.
>
> Note that expand_vec_cond_expr_p doesn't rely on enum insn code.  Well, it
> relies on enum insn code being an integer and CODE_FOR_nothing always having
> the value zero, which is probably worse.

Actually it also uses CODE_FOR_nothing in comparison:

  || get_vcond_icode (TYPE_MODE (value_type), TYPE_MODE (cmp_op_type),
  TYPE_UNSIGNED (cmp_op_type)) == CODE_FOR_nothing)

There are also two other instances of CODE_FOR_nothing in
optabs-tree.c. Do you want to get rid of "#include insn-codes.h" in
optabs-tree.c? Will it be really better if we replace it with
"#include optabs-query.h"?

Thanks,
Ilya

>
> We should clean both of these up so that:
>
>   1. We don't need enum insn_code in optabs-tree
>   2. We don't implicitly rely on CODE_FOR_nothing == 0
>
> It may be as simple as a adding a predicate function to optabs-query that
> returns true/false if there's a suitable icode, then using that predicate in
> optabs-tree.
>
> jeff
>
>

Re: [vec-cmp, patch 1/6] Add optabs for vector comparison

[Jeff Law]

On 10/08/2015 08:52 AM, Ilya Enkovich wrote:

Hi,

This series introduces autogeneration of vector comparison and its support on 
i386 target.  It lets comparison statements to be vectorized into vector 
comparison instead of VEC_COND_EXPR.  This allows to avoid some restrictions 
implied by boolean patterns.  This series applies on top of bolean vectors 
series [1].

This patch introduces optabs for vector comparison.

[1] https://gcc.gnu.org/ml/gcc-patches/2015-10/msg00215.html

Thanks,
Ilya
--
gcc/

2015-10-08  Ilya Enkovich  

* expr.c (do_store_flag): Use expand_vec_cmp_expr for mask results.
* optabs-query.h (get_vec_cmp_icode): New.
* optabs-tree.c (expand_vec_cmp_expr_p): New.
* optabs-tree.h (expand_vec_cmp_expr_p): New.
* optabs.c (vector_compare_rtx): Add OPNO arg.
(expand_vec_cond_expr): Adjust to vector_compare_rtx change.
(expand_vec_cmp_expr): New.
* optabs.def (vec_cmp_optab): New.
(vec_cmpu_optab): New.
* optabs.h (expand_vec_cmp_expr): New.
* tree-vect-generic.c (expand_vector_comparison): Add vector
comparison optabs check.


diff --git a/gcc/optabs-tree.c b/gcc/optabs-tree.c
index 3b03338..aa863cf 100644
--- a/gcc/optabs-tree.c
+++ b/gcc/optabs-tree.c
@@ -320,6 +320,19 @@ supportable_convert_operation (enum tree_code code,
return false;
  }

+/* Return TRUE if appropriate vector insn is available
+   for vector comparison expr with vector type VALUE_TYPE
+   and resulting mask with MASK_TYPE.  */
+
+bool
+expand_vec_cmp_expr_p (tree value_type, tree mask_type)
+{
+  enum insn_code icode = get_vec_cmp_icode (TYPE_MODE (value_type),
+   TYPE_MODE (mask_type),
+   TYPE_UNSIGNED (value_type));
+  return (icode != CODE_FOR_nothing);
+}
+
Nothing inherently wrong with the code, but it seems like it's in the 
wrong place.  Why optabs-tree rather than optabs-query?


I think with that fixed this patch will be ready to go onto the trunk.

jeff

[vec-cmp, patch 1/6] Add optabs for vector comparison

[Ilya Enkovich]

Hi,

This series introduces autogeneration of vector comparison and its support on 
i386 target.  It lets comparison statements to be vectorized into vector 
comparison instead of VEC_COND_EXPR.  This allows to avoid some restrictions 
implied by boolean patterns.  This series applies on top of bolean vectors 
series [1].

This patch introduces optabs for vector comparison.

[1] https://gcc.gnu.org/ml/gcc-patches/2015-10/msg00215.html

Thanks,
Ilya
--
gcc/

2015-10-08  Ilya Enkovich  

* expr.c (do_store_flag): Use expand_vec_cmp_expr for mask results.
* optabs-query.h (get_vec_cmp_icode): New.
* optabs-tree.c (expand_vec_cmp_expr_p): New.
* optabs-tree.h (expand_vec_cmp_expr_p): New.
* optabs.c (vector_compare_rtx): Add OPNO arg.
(expand_vec_cond_expr): Adjust to vector_compare_rtx change.
(expand_vec_cmp_expr): New.
* optabs.def (vec_cmp_optab): New.
(vec_cmpu_optab): New.
* optabs.h (expand_vec_cmp_expr): New.
* tree-vect-generic.c (expand_vector_comparison): Add vector
comparison optabs check.


diff --git a/gcc/expr.c b/gcc/expr.c
index 0bbfccd..88da8cb 100644
--- a/gcc/expr.c
+++ b/gcc/expr.c
@@ -11025,9 +11025,15 @@ do_store_flag (sepops ops, rtx target, machine_mode 
mode)
   if (TREE_CODE (ops->type) == VECTOR_TYPE)
 {
   tree ifexp = build2 (ops->code, ops->type, arg0, arg1);
-  tree if_true = constant_boolean_node (true, ops->type);
-  tree if_false = constant_boolean_node (false, ops->type);
-  return expand_vec_cond_expr (ops->type, ifexp, if_true, if_false, 
target);
+  if (VECTOR_BOOLEAN_TYPE_P (ops->type))
+   return expand_vec_cmp_expr (ops->type, ifexp, target);
+  else
+   {
+ tree if_true = constant_boolean_node (true, ops->type);
+ tree if_false = constant_boolean_node (false, ops->type);
+ return expand_vec_cond_expr (ops->type, ifexp, if_true,
+  if_false, target);
+   }
 }
 
   /* Get the rtx comparison code to use.  We know that EXP is a comparison
diff --git a/gcc/optabs-query.h b/gcc/optabs-query.h
index 73f2729..81ac362 100644
--- a/gcc/optabs-query.h
+++ b/gcc/optabs-query.h
@@ -74,6 +74,16 @@ trapv_binoptab_p (optab binoptab)
  || binoptab == smulv_optab);
 }
 
+/* Return insn code for a comparison operator with VMODE
+   resultin MASK_MODE, unsigned if UNS is true.  */
+
+static inline enum insn_code
+get_vec_cmp_icode (machine_mode vmode, machine_mode mask_mode, bool uns)
+{
+  optab tab = uns ? vec_cmpu_optab : vec_cmp_optab;
+  return convert_optab_handler (tab, vmode, mask_mode);
+}
+
 /* Return insn code for a conditional operator with a comparison in
mode CMODE, unsigned if UNS is true, resulting in a value of mode VMODE.  */
 
diff --git a/gcc/optabs-tree.c b/gcc/optabs-tree.c
index 3b03338..aa863cf 100644
--- a/gcc/optabs-tree.c
+++ b/gcc/optabs-tree.c
@@ -320,6 +320,19 @@ supportable_convert_operation (enum tree_code code,
   return false;
 }
 
+/* Return TRUE if appropriate vector insn is available
+   for vector comparison expr with vector type VALUE_TYPE
+   and resulting mask with MASK_TYPE.  */
+
+bool
+expand_vec_cmp_expr_p (tree value_type, tree mask_type)
+{
+  enum insn_code icode = get_vec_cmp_icode (TYPE_MODE (value_type),
+   TYPE_MODE (mask_type),
+   TYPE_UNSIGNED (value_type));
+  return (icode != CODE_FOR_nothing);
+}
+
 /* Return TRUE iff, appropriate vector insns are available
for vector cond expr with vector type VALUE_TYPE and a comparison
with operand vector types in CMP_OP_TYPE.  */
diff --git a/gcc/optabs-tree.h b/gcc/optabs-tree.h
index bf6c9e3..5b966ca 100644
--- a/gcc/optabs-tree.h
+++ b/gcc/optabs-tree.h
@@ -39,6 +39,7 @@ optab optab_for_tree_code (enum tree_code, const_tree, enum 
optab_subtype);
 optab scalar_reduc_to_vector (optab, const_tree);
 bool supportable_convert_operation (enum tree_code, tree, tree, tree *,
enum tree_code *);
+bool expand_vec_cmp_expr_p (tree, tree);
 bool expand_vec_cond_expr_p (tree, tree);
 void init_tree_optimization_optabs (tree);
 
diff --git a/gcc/optabs.c b/gcc/optabs.c
index 8d9d742..ca1a6e7 100644
--- a/gcc/optabs.c
+++ b/gcc/optabs.c
@@ -5100,11 +5100,13 @@ get_rtx_code (enum tree_code tcode, bool unsignedp)
 }
 
 /* Return comparison rtx for COND. Use UNSIGNEDP to select signed or
-   unsigned operators. Do not generate compare instruction.  */
+   unsigned operators.  OPNO holds an index of the first comparison
+   operand in insn with code ICODE.  Do not generate compare instruction.  */
 
 static rtx
 vector_compare_rtx (enum tree_code tcode, tree t_op0, tree t_op1,
-   bool unsignedp, enum insn_code icode)
+   bool unsignedp, enum insn_code icode,
+   unsigned int opno)
 {
   struct