diff mbox

[libfortran] Fix amount of memory allocation for matrix - vector calculation

Message ID 460358d6-6691-7a7d-75f0-dcbb32aba081@netcologne.de
State New
Headers show

Commit Message

Thomas Koenig May 12, 2017, 4:57 p.m. UTC 
Am 12.05.2017 um 10:16 schrieb Janne Blomqvist:
> On Fri, May 12, 2017 at 1:14 AM, Thomas Koenig <tkoenig@netcologne.de> wrote:
>> Hello world,
>>
>> the memory allocation for the buffer in the library matmul
>> routines still has one problem: The value of 0xdeadbeef meant
>> as poison could end up in the calculation of the size of the
>> buffer for the blocked matmul.
>>
>> The attached patch fixes that. Verified with regression-test,
>> also by running a few select test cases under valgrind.
>>
>> No test case because nothing appeared to fail.
>>
>> OK for trunk?
> 
> Patch missing?

Well, yes.

Here it is.

Regards

	Thomas

Comments

H.J. Lu May 15, 2017, 3:49 p.m. UTC | #1 
On Fri, May 12, 2017 at 9:57 AM, Thomas Koenig <tkoenig@netcologne.de> wrote:
> Am 12.05.2017 um 10:16 schrieb Janne Blomqvist:
>>
>> On Fri, May 12, 2017 at 1:14 AM, Thomas Koenig <tkoenig@netcologne.de>
>> wrote:
>>>
>>> Hello world,
>>>
>>> the memory allocation for the buffer in the library matmul
>>> routines still has one problem: The value of 0xdeadbeef meant
>>> as poison could end up in the calculation of the size of the
>>> buffer for the blocked matmul.
>>>
>>> The attached patch fixes that. Verified with regression-test,
>>> also by running a few select test cases under valgrind.
>>>
>>> No test case because nothing appeared to fail.
>>>
>>> OK for trunk?
>>
>>
>> Patch missing?
>
>
> Well, yes.
>
> Here it is.
>
> Regards
>
>         Thomas
>

This fixes:

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80765
Janne Blomqvist May 15, 2017, 4:28 p.m. UTC | #2 
On Fri, May 12, 2017 at 7:57 PM, Thomas Koenig <tkoenig@netcologne.de> wrote:
> Am 12.05.2017 um 10:16 schrieb Janne Blomqvist:
>>
>> On Fri, May 12, 2017 at 1:14 AM, Thomas Koenig <tkoenig@netcologne.de>
>> wrote:
>>>
>>> Hello world,
>>>
>>> the memory allocation for the buffer in the library matmul
>>> routines still has one problem: The value of 0xdeadbeef meant
>>> as poison could end up in the calculation of the size of the
>>> buffer for the blocked matmul.
>>>
>>> The attached patch fixes that. Verified with regression-test,
>>> also by running a few select test cases under valgrind.
>>>
>>> No test case because nothing appeared to fail.
>>>
>>> OK for trunk?
>>
>>
>> Patch missing?
>
>
> Well, yes.
>
> Here it is.

Looks good, Ok for trunk.

Also add PR 80765 to the changelog per HJL's message.
diff mbox

Patch

Index: generated/matmul_c10.c
===================================================================
--- generated/matmul_c10.c	(Revision 247839)
+++ generated/matmul_c10.c	(Arbeitskopie)
@@ -222,9 +222,9 @@  matmul_c10_avx (gfc_array_c10 * const restrict ret
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -774,9 +774,9 @@  matmul_c10_avx2 (gfc_array_c10 * const restrict re
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -1326,9 +1326,9 @@  matmul_c10_avx512f (gfc_array_c10 * const restrict
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -1874,9 +1874,9 @@  matmul_c10_vanilla (gfc_array_c10 * const restrict
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -2480,9 +2480,9 @@  matmul_c10 (gfc_array_c10 * const restrict retarra
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
Index: generated/matmul_c16.c
===================================================================
--- generated/matmul_c16.c	(Revision 247839)
+++ generated/matmul_c16.c	(Arbeitskopie)
@@ -222,9 +222,9 @@  matmul_c16_avx (gfc_array_c16 * const restrict ret
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -774,9 +774,9 @@  matmul_c16_avx2 (gfc_array_c16 * const restrict re
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -1326,9 +1326,9 @@  matmul_c16_avx512f (gfc_array_c16 * const restrict
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -1874,9 +1874,9 @@  matmul_c16_vanilla (gfc_array_c16 * const restrict
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -2480,9 +2480,9 @@  matmul_c16 (gfc_array_c16 * const restrict retarra
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
Index: generated/matmul_c4.c
===================================================================
--- generated/matmul_c4.c	(Revision 247839)
+++ generated/matmul_c4.c	(Arbeitskopie)
@@ -222,9 +222,9 @@  matmul_c4_avx (gfc_array_c4 * const restrict retar
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -774,9 +774,9 @@  matmul_c4_avx2 (gfc_array_c4 * const restrict reta
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -1326,9 +1326,9 @@  matmul_c4_avx512f (gfc_array_c4 * const restrict r
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -1874,9 +1874,9 @@  matmul_c4_vanilla (gfc_array_c4 * const restrict r
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -2480,9 +2480,9 @@  matmul_c4 (gfc_array_c4 * const restrict retarray,
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
Index: generated/matmul_c8.c
===================================================================
--- generated/matmul_c8.c	(Revision 247839)
+++ generated/matmul_c8.c	(Arbeitskopie)
@@ -222,9 +222,9 @@  matmul_c8_avx (gfc_array_c8 * const restrict retar
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -774,9 +774,9 @@  matmul_c8_avx2 (gfc_array_c8 * const restrict reta
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -1326,9 +1326,9 @@  matmul_c8_avx512f (gfc_array_c8 * const restrict r
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -1874,9 +1874,9 @@  matmul_c8_vanilla (gfc_array_c8 * const restrict r
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -2480,9 +2480,9 @@  matmul_c8 (gfc_array_c8 * const restrict retarray,
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
Index: generated/matmul_i1.c
===================================================================
--- generated/matmul_i1.c	(Revision 247839)
+++ generated/matmul_i1.c	(Arbeitskopie)
@@ -222,9 +222,9 @@  matmul_i1_avx (gfc_array_i1 * const restrict retar
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -774,9 +774,9 @@  matmul_i1_avx2 (gfc_array_i1 * const restrict reta
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -1326,9 +1326,9 @@  matmul_i1_avx512f (gfc_array_i1 * const restrict r
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -1874,9 +1874,9 @@  matmul_i1_vanilla (gfc_array_i1 * const restrict r
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -2480,9 +2480,9 @@  matmul_i1 (gfc_array_i1 * const restrict retarray,
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
Index: generated/matmul_i16.c
===================================================================
--- generated/matmul_i16.c	(Revision 247839)
+++ generated/matmul_i16.c	(Arbeitskopie)
@@ -222,9 +222,9 @@  matmul_i16_avx (gfc_array_i16 * const restrict ret
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -774,9 +774,9 @@  matmul_i16_avx2 (gfc_array_i16 * const restrict re
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -1326,9 +1326,9 @@  matmul_i16_avx512f (gfc_array_i16 * const restrict
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -1874,9 +1874,9 @@  matmul_i16_vanilla (gfc_array_i16 * const restrict
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -2480,9 +2480,9 @@  matmul_i16 (gfc_array_i16 * const restrict retarra
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
Index: generated/matmul_i2.c
===================================================================
--- generated/matmul_i2.c	(Revision 247839)
+++ generated/matmul_i2.c	(Arbeitskopie)
@@ -222,9 +222,9 @@  matmul_i2_avx (gfc_array_i2 * const restrict retar
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -774,9 +774,9 @@  matmul_i2_avx2 (gfc_array_i2 * const restrict reta
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -1326,9 +1326,9 @@  matmul_i2_avx512f (gfc_array_i2 * const restrict r
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -1874,9 +1874,9 @@  matmul_i2_vanilla (gfc_array_i2 * const restrict r
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -2480,9 +2480,9 @@  matmul_i2 (gfc_array_i2 * const restrict retarray,
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
Index: generated/matmul_i4.c
===================================================================
--- generated/matmul_i4.c	(Revision 247839)
+++ generated/matmul_i4.c	(Arbeitskopie)
@@ -222,9 +222,9 @@  matmul_i4_avx (gfc_array_i4 * const restrict retar
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -774,9 +774,9 @@  matmul_i4_avx2 (gfc_array_i4 * const restrict reta
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -1326,9 +1326,9 @@  matmul_i4_avx512f (gfc_array_i4 * const restrict r
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -1874,9 +1874,9 @@  matmul_i4_vanilla (gfc_array_i4 * const restrict r
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -2480,9 +2480,9 @@  matmul_i4 (gfc_array_i4 * const restrict retarray,
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
Index: generated/matmul_i8.c
===================================================================
--- generated/matmul_i8.c	(Revision 247839)
+++ generated/matmul_i8.c	(Arbeitskopie)
@@ -222,9 +222,9 @@  matmul_i8_avx (gfc_array_i8 * const restrict retar
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -774,9 +774,9 @@  matmul_i8_avx2 (gfc_array_i8 * const restrict reta
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -1326,9 +1326,9 @@  matmul_i8_avx512f (gfc_array_i8 * const restrict r
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -1874,9 +1874,9 @@  matmul_i8_vanilla (gfc_array_i8 * const restrict r
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -2480,9 +2480,9 @@  matmul_i8 (gfc_array_i8 * const restrict retarray,
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
Index: generated/matmul_r10.c
===================================================================
--- generated/matmul_r10.c	(Revision 247839)
+++ generated/matmul_r10.c	(Arbeitskopie)
@@ -222,9 +222,9 @@  matmul_r10_avx (gfc_array_r10 * const restrict ret
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -774,9 +774,9 @@  matmul_r10_avx2 (gfc_array_r10 * const restrict re
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -1326,9 +1326,9 @@  matmul_r10_avx512f (gfc_array_r10 * const restrict
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -1874,9 +1874,9 @@  matmul_r10_vanilla (gfc_array_r10 * const restrict
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -2480,9 +2480,9 @@  matmul_r10 (gfc_array_r10 * const restrict retarra
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
Index: generated/matmul_r16.c
===================================================================
--- generated/matmul_r16.c	(Revision 247839)
+++ generated/matmul_r16.c	(Arbeitskopie)
@@ -222,9 +222,9 @@  matmul_r16_avx (gfc_array_r16 * const restrict ret
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -774,9 +774,9 @@  matmul_r16_avx2 (gfc_array_r16 * const restrict re
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -1326,9 +1326,9 @@  matmul_r16_avx512f (gfc_array_r16 * const restrict
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -1874,9 +1874,9 @@  matmul_r16_vanilla (gfc_array_r16 * const restrict
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -2480,9 +2480,9 @@  matmul_r16 (gfc_array_r16 * const restrict retarra
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
Index: generated/matmul_r4.c
===================================================================
--- generated/matmul_r4.c	(Revision 247839)
+++ generated/matmul_r4.c	(Arbeitskopie)
@@ -222,9 +222,9 @@  matmul_r4_avx (gfc_array_r4 * const restrict retar
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -774,9 +774,9 @@  matmul_r4_avx2 (gfc_array_r4 * const restrict reta
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -1326,9 +1326,9 @@  matmul_r4_avx512f (gfc_array_r4 * const restrict r
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -1874,9 +1874,9 @@  matmul_r4_vanilla (gfc_array_r4 * const restrict r
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -2480,9 +2480,9 @@  matmul_r4 (gfc_array_r4 * const restrict retarray,
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
Index: generated/matmul_r8.c
===================================================================
--- generated/matmul_r8.c	(Revision 247839)
+++ generated/matmul_r8.c	(Arbeitskopie)
@@ -222,9 +222,9 @@  matmul_r8_avx (gfc_array_r8 * const restrict retar
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -774,9 +774,9 @@  matmul_r8_avx2 (gfc_array_r8 * const restrict reta
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -1326,9 +1326,9 @@  matmul_r8_avx512f (gfc_array_r8 * const restrict r
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -1874,9 +1874,9 @@  matmul_r8_vanilla (gfc_array_r8 * const restrict r
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
@@ -2480,9 +2480,9 @@  matmul_r8 (gfc_array_r8 * const restrict retarray,
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else
Index: m4/matmul_internal.m4
===================================================================
--- m4/matmul_internal.m4	(Revision 247839)
+++ m4/matmul_internal.m4	(Arbeitskopie)
@@ -138,9 +138,9 @@  sinclude(`matmul_asm_'rtype_code`.m4')dnl
       bxstride = GFC_DESCRIPTOR_STRIDE(b,0);
 
       /* bystride should never be used for 1-dimensional b.
-	 in case it is we want it to cause a segfault, rather than
-	 an incorrect result. */
-      bystride = 0xDEADBEEF;
+         The value is only used for calculation of the
+         memory by the buffer.  */
+      bystride = 256;
       ycount = 1;
     }
   else