David Faust writes:
> On 3/13/24 07:24, Cupertino Miranda wrote:
>> Any unnamed structure field if not a member of the BTF_KIND_STRUCT.
> typo: if -> is
>
> I'd suggest to clarify that "any unnamed structure field" is really
> any unnamed non-struct-or-union field, since anonymous inner structs
> and unions certainly are present in BTF (and you handle them here).
>
>> For that reason, CO-RE access strings indexes should take that in
>> consideration. This patch adds a condition to the incrementer that
>> computes the index for the field access.
>
> Otherwise, OK.
> Thanks.
Corrected and Pushed. Thanks
>
>>
>> gcc/ChangeLog:
>> * config/bpf/core-builtins.cc (bpf_core_get_index): Check if
>> field contains a DECL_NAME.
>>
>> gcc/testsuite/ChangeLog:
>> * gcc.target/bpf/core-builtin-fieldinfo-offset-1.c: Add
>> testcase for unnamed fields.
>> ---
>> gcc/config/bpf/core-builtins.cc | 6 +++++-
>> .../gcc.target/bpf/core-builtin-fieldinfo-offset-1.c | 10 ++++++++--
>> 2 files changed, 13 insertions(+), 3 deletions(-)
>>
>> diff --git a/gcc/config/bpf/core-builtins.cc
>> b/gcc/config/bpf/core-builtins.cc
>> index 70b14e48e6e5..8333ad81d0e0 100644
>> --- a/gcc/config/bpf/core-builtins.cc
>> +++ b/gcc/config/bpf/core-builtins.cc
>> @@ -553,7 +553,11 @@ bpf_core_get_index (const tree node, bool *valid)
>> {
>> if (l == node)
>> return i;
>> - i++;
>> + /* Skip unnamed padding, not represented by BTF. */
>> + if (DECL_NAME(l) != NULL_TREE
>> + || TREE_CODE (TREE_TYPE (l)) == UNION_TYPE
>> + || TREE_CODE (TREE_TYPE (l)) == RECORD_TYPE)
>> + i++;
>> }
>> }
>> else if (code == ARRAY_REF || code == ARRAY_RANGE_REF || code == MEM_REF)
>> diff --git a/gcc/testsuite/gcc.target/bpf/core-builtin-fieldinfo-offset-1.c
>> b/gcc/testsuite/gcc.target/bpf/core-builtin-fieldinfo-offset-1.c
>> index 27654205287d..8b1d8b012a2a 100644
>> --- a/gcc/testsuite/gcc.target/bpf/core-builtin-fieldinfo-offset-1.c
>> +++ b/gcc/testsuite/gcc.target/bpf/core-builtin-fieldinfo-offset-1.c
>> @@ -14,6 +14,9 @@ struct T {
>> struct S s[2];
>> char c;
>> char d;
>> + int a: 1;
>> + int:31;
>> + int f;
>> };
>>
>> enum {
>> @@ -38,7 +41,9 @@ unsigned int foo (struct T *t)
>> unsigned e1 = __builtin_preserve_field_info (bar()->d, FIELD_BYTE_OFFSET);
>> unsigned e2 = __builtin_preserve_field_info (bar()->s[1].a4,
>> FIELD_BYTE_OFFSET);
>>
>> - return s0a1 + s0a4 + s0x + s1a1 + s1a4 + s1x + c + d + e1 + e2;
>> + unsigned f1 = __builtin_preserve_field_info (t->f, FIELD_BYTE_OFFSET);
>> +
>> + return s0a1 + s0a4 + s0x + s1a1 + s1a4 + s1x + c + d + e1 + e2 + f1;
>> }
>>
>> /* { dg-final { scan-assembler-times "\[\t \]mov\[\t \]%r\[0-9\],4" 2 } } */
>> @@ -65,5 +70,6 @@ unsigned int foo (struct T *t)
>> /* { dg-final { scan-assembler-times "bpfcr_astr_off \\(\"0:1:1:4\"\\)" 1 }
>> } */
>> /* { dg-final { scan-assembler-times "bpfcr_astr_off \\(\"0:2\"\\)" 1 } } */
>> /* { dg-final { scan-assembler-times "bpfcr_astr_off \\(\"0:3\"\\)" 2 } } */
>> +/* { dg-final { scan-assembler-times "bpfcr_astr_off \\(\"0:5\"\\)" 1 } } */
>>
>> -/* { dg-final { scan-assembler-times "0\[\t \]+\[^\n\]*bpfcr_kind" 10 } } */
>> +/* { dg-final { scan-assembler-times "0\[\t \]+\[^\n\]*bpfcr_kind" 11 } } */
