[PATCH] pdp11: Fix handling of common (local and global) vars [PR94134]

[Paul Koning]

Ok, thanks.  

	paul

> On Mar 11, 2020, at 1:12 PM, Jakub Jelinek <jakub@redhat.com> wrote:
> 
> Hi!
> 
> As mentioned in the PR, the generic code decides to put the a variable into
> lcomm_section, which is a NOSWITCH section and thus the generic code doesn't
> switch into a particular section before using
> ASM_OUTPUT{_ALIGNED{,_DECL}_}_LOCAL, on many targets that results just in
> .lcomm (or for non-local .comm) directives which don't need a switch to some
> section, other targets put switch_to_section (bss_section) at the start of
> that macro.
> pdp11 doesn't do that (and doesn't have bss_section), and so emits the
> lcomm/comm variables in whatever section is current (it has only .text/.data
> and for DEC assembler rodata).
> 
> The following patch fixes that by putting it always into data section, and
> additionally avoids emitting an empty line in the assembly for the lcomm
> vars.
> 
> Tested on the testcase, I'm afraid I have no other way to test this target.
> Ok for trunk?
> 
> 2020-03-11  Jakub Jelinek  <jakub@redhat.com>
> 
> 	PR target/94134
> 	* config/pdp11/pdp11.c (pdp11_asm_output_var): Call switch_to_section
> 	at the start to switch to data section.  Don't print extra newline if
> 	.globl directive has not been emitted.
> 
> 	* gcc.c-torture/execute/pr94134.c: New test.
> 
> --- gcc/config/pdp11/pdp11.c.jj	2020-01-12 11:54:36.382413876 +0100
> +++ gcc/config/pdp11/pdp11.c	2020-03-11 15:44:43.373970000 +0100
> @@ -743,6 +743,7 @@ void
> pdp11_asm_output_var (FILE *file, const char *name, int size,
> 		      int align, bool global)
> {
> +  switch_to_section (data_section);
>   if (align > 8)
>     fprintf (file, "\t.even\n");
>   if (TARGET_DEC_ASM)
> @@ -763,8 +764,8 @@ pdp11_asm_output_var (FILE *file, const
> 	{
> 	  fprintf (file, ".globl ");
> 	  assemble_name (file, name);
> +	  fprintf (file, "\n");
> 	}
> -      fprintf (file, "\n");
>       assemble_name (file, name);
>       fputs (":", file);
>       ASM_OUTPUT_SKIP (file, size);
> --- gcc/testsuite/gcc.c-torture/execute/pr94134.c.jj	2020-03-11 15:46:09.540710642 +0100
> +++ gcc/testsuite/gcc.c-torture/execute/pr94134.c	2020-03-11 15:40:18.538840663 +0100
> @@ -0,0 +1,14 @@
> +/* PR target/94134 */
> +
> +static volatile int a = 0;
> +static volatile int b = 1;
> +
> +int
> +main ()
> +{
> +  a++;
> +  b++;
> +  if (a != 1 || b != 2)
> +    __builtin_abort ();
> +  return 0;
> +}
> 
> 	Jakub
>