[PING^2][PATCH][final] Handle compiler-generated asm insn

[Tom de Vries <tdevries@suse.de>]

On 3/9/22 13:50, Tom de Vries wrote:
> On 2/22/22 14:55, Tom de Vries wrote:
>> Hi,
>>
>> For the nvptx port, with -mptx-comment we have in pr53465.s:
>> ...
>>          // #APP
>> // 9 "gcc/testsuite/gcc.c-torture/execute/pr53465.c" 1
>>          // Start: Added by -minit-regs=3:
>>          // #NO_APP
>>                  mov.u32 %r26, 0;
>>          // #APP
>> // 9 "gcc/testsuite/gcc.c-torture/execute/pr53465.c" 1
>>          // End: Added by -minit-regs=3:
>>          // #NO_APP
>> ...
>>
>> The comments where generated using the compiler-generated equivalent of:
>> ...
>>    asm ("// Comment");
>> ...
>> but both the printed location and the NO_APP/APP are unnecessary for a
>> compiler-generated asm insn.
>>
>> Fix this by handling ASM_INPUT_SOURCE_LOCATION == UNKNOWN_LOCATION in
>> final_scan_insn_1, such what we simply get:
>> ...
>>          // Start: Added by -minit-regs=3:
>>                  mov.u32 %r26, 0;
>>          // End: Added by -minit-regs=3:
>> ...
>>
>> Tested on nvptx.
>>
>> OK for trunk?
>>
> 

Ping^2.

Tobias just reported an ICE in PR104968, and this patch fixes it.

I'd like to known whether this patch is acceptable for stage 4 or not.

If not, I need to fix PR104968 in a different way.  Say, disable 
-mcomment by default, or trying harder to propagate source info on 
outlined functions.

Thanks,
- Tom

>> [final] Handle compiler-generated asm insn
>>
>> gcc/ChangeLog:
>>
>> 2022-02-21  Tom de Vries  <tdevries@suse.de>
>>
>>     PR rtl-optimization/104596
>>     * config/nvptx/nvptx.cc (gen_comment): Use gen_rtx_ASM_INPUT instead
>>     of gen_rtx_ASM_INPUT_loc.
>>     * final.cc (final_scan_insn_1): Handle
>>     ASM_INPUT_SOURCE_LOCATION == UNKNOWN_LOCATION.
>>
>> ---
>>   gcc/config/nvptx/nvptx.cc |  3 +--
>>   gcc/final.cc              | 17 +++++++++++------
>>   2 files changed, 12 insertions(+), 8 deletions(-)
>>
>> diff --git a/gcc/config/nvptx/nvptx.cc b/gcc/config/nvptx/nvptx.cc
>> index 858789e6df7..4124c597f24 100644
>> --- a/gcc/config/nvptx/nvptx.cc
>> +++ b/gcc/config/nvptx/nvptx.cc
>> @@ -5381,8 +5381,7 @@ gen_comment (const char *s)
>>     size_t len = strlen (ASM_COMMENT_START) + strlen (sep) + strlen 
>> (s) + 1;
>>     char *comment = (char *) alloca (len);
>>     snprintf (comment, len, "%s%s%s", ASM_COMMENT_START, sep, s);
>> -  return gen_rtx_ASM_INPUT_loc (VOIDmode, ggc_strdup (comment),
>> -                cfun->function_start_locus);
>> +  return gen_rtx_ASM_INPUT (VOIDmode, ggc_strdup (comment));
>>   }
>>   /* Initialize all declared regs at function entry.
>> diff --git a/gcc/final.cc b/gcc/final.cc
>> index a9868861bd2..e6443ef7a4f 100644
>> --- a/gcc/final.cc
>> +++ b/gcc/final.cc
>> @@ -2642,15 +2642,20 @@ final_scan_insn_1 (rtx_insn *insn, FILE *file, 
>> int optimize_p ATTRIBUTE_UNUSED,
>>           if (string[0])
>>             {
>>           expanded_location loc;
>> +        bool unknown_loc_p
>> +          = ASM_INPUT_SOURCE_LOCATION (body) == UNKNOWN_LOCATION;
>> -        app_enable ();
>> -        loc = expand_location (ASM_INPUT_SOURCE_LOCATION (body));
>> -        if (*loc.file && loc.line)
>> -          fprintf (asm_out_file, "%s %i \"%s\" 1\n",
>> -               ASM_COMMENT_START, loc.line, loc.file);
>> +        if (!unknown_loc_p)
>> +          {
>> +            app_enable ();
>> +            loc = expand_location (ASM_INPUT_SOURCE_LOCATION (body));
>> +            if (*loc.file && loc.line)
>> +              fprintf (asm_out_file, "%s %i \"%s\" 1\n",
>> +                   ASM_COMMENT_START, loc.line, loc.file);
>> +          }
>>           fprintf (asm_out_file, "\t%s\n", string);
>>   #if HAVE_AS_LINE_ZERO
>> -        if (*loc.file && loc.line)
>> +        if (!unknown_loc_p && loc.file && *loc.file && loc.line)
>>             fprintf (asm_out_file, "%s 0 \"\" 2\n", ASM_COMMENT_START);
>>   #endif
>>             }