On 03/27/2018 01:17 AM, Tom de Vries wrote:
> On 03/26/2018 11:57 PM, Cesar Philippidis wrote:
>> As noted in PR85056, the nvptx BE isn't declaring external arrays using
>> PTX array notation. Specifically, it's emitting code that's missing the
>> empty angle brackets '[]'.
>
> [ FYI, see https://en.wikipedia.org/wiki/Bracket
>
> For '[]' I find "square brackets, closed brackets, hard brackets, third
> brackets, crotchets, or brackets (US)".
>
> Angle brackets are different symbols. ]
Sorry, you're correct. I meant square brackets.
>> This patch corrects that problem.
>>
>> Tom, in contrast to my earlier patch in the PR, this patch only
>> considers external arrays. The patch I posted incorrectly handled
>> zero-length arrays and empty structs.
>>
>> I tested this patch with a standalone nvptx toolchain using newlib 3.0,
>> and I found no new regressions. However I'm still waiting for the
>> results that are using the older version of newlib. Is this patch OK for
>> trunk if the results come back clean?
>>
>
> OK for stage4 trunk.
Can I backport this patch to GCC 6 and 7? That fix is necessary to build
an updated version of newlib that I'm working on.
Thanks,
Cesar
> [ A minor style nit: in submission emails, rather than having the very
> specific but rather non-descriptive subject "Fix PR85056", move the PR
> number to "[PATCH,nvptx,PR85056]" and add a subject line that describes
> the nature of the patch, f.i.: "Fix declaration of external array with
> unknown size".
>
> So, something like:
> ...
> [PATCH,nvptx,PR85056] Fix declaration of external array with unknown size
> ...
>
> Then, use the subject line as commit log header line (dropping "PATCH",
> and the PR number):
> ...
> [nvptx] Fix declaration of external array with unknown size
> ...
> ]
>
> Thanks,
> - Tom
>
>> Thanks,
>> Cesar
>>
>>
>> nvptx-extern-arrays.diff
>>
>>
>> 2018-03-26 Cesar Philippidis <ce...@codesourcery.com>
>>
>> gcc/
>>
>> PR target/85056
>> * config/nvptx/nvptx.c (nvptx_assemble_decl_begin): Add '[]' to
>> extern array declarations.
>>
>> gcc/testsuite/
>> * testsuite/gcc.target/nvptx/pr85056.c: New test.
>> * testsuite/gcc.target/nvptx/pr85056a.c: New test.
>>
>>
>> diff --git a/gcc/config/nvptx/nvptx.c b/gcc/config/nvptx/nvptx.c
>> index 3cb33ae8c2d..38f25add6ab 100644
>> --- a/gcc/config/nvptx/nvptx.c
>> +++ b/gcc/config/nvptx/nvptx.c
>> @@ -2038,6 +2038,9 @@ static void
>> nvptx_assemble_decl_begin (FILE *file, const char *name, const char
>> *section,
>> const_tree type, HOST_WIDE_INT size, unsigned align)
>> {
>> + bool atype = (TREE_CODE (type) == ARRAY_TYPE)
>> + && (TYPE_DOMAIN (type) == NULL_TREE);
>> +
>> while (TREE_CODE (type) == ARRAY_TYPE)
>> type = TREE_TYPE (type);
>> @@ -2077,6 +2080,8 @@ nvptx_assemble_decl_begin (FILE *file, const
>> char *name, const char *section,
>> /* We make everything an array, to simplify any initialization
>> emission. */
>> fprintf (file, "[" HOST_WIDE_INT_PRINT_DEC "]",
>> init_frag.remaining);
>> + else if (atype)
>> + fprintf (file, "[]");
>> }
>> /* Called when the initializer for a decl has been completely
>> output through
>> diff --git a/gcc/testsuite/gcc.target/nvptx/pr85056.c
>> b/gcc/testsuite/gcc.target/nvptx/pr85056.c
>> new file mode 100644
>> index 00000000000..fe7f8af856e
>> --- /dev/null
>> +++ b/gcc/testsuite/gcc.target/nvptx/pr85056.c
>> @@ -0,0 +1,20 @@
>> +/* { dg-do run } */
>> +/* { dg-additional-sources "pr85056a.c" } */
>> +
>> +extern void abort ();
>> +
>> +extern int a[];
>> +
>> +int
>> +main ()
>> +{
>> + int i, sum;
>> +
>> + for (i = 0; i < 10; i++)
>> + sum += a[i];
>> +
>> + if (sum != 55)
>> + abort ();
>> +
>> + return 0;
>> +}
>> diff --git a/gcc/testsuite/gcc.target/nvptx/pr85056a.c
>> b/gcc/testsuite/gcc.target/nvptx/pr85056a.c
>> new file mode 100644
>> index 00000000000..a45a5f2b07f
>> --- /dev/null
>> +++ b/gcc/testsuite/gcc.target/nvptx/pr85056a.c
>> @@ -0,0 +1,3 @@
>> +/* { dg-skip-if "" { *-*-* } } */
>> +
>> +int a[10] = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };
>>
>
