Re: [Mesa3d-dev] Mesa (master): mesa: Remove pointless comparison of unsigned integer with a negative constant.

[Brian P. <br...@vm...>]

Vinson Lee wrote:
>> -----Original Message-----
>>
>>> mesa: Remove pointless comparison of unsigned integer with a negative
>> constant.
>>> ---
>>>
>>>  src/mesa/shader/prog_execute.c |   13 ++++---------
>>>  1 files changed, 4 insertions(+), 9 deletions(-)
>>>
>>> diff --git a/src/mesa/shader/prog_execute.c
>> b/src/mesa/shader/prog_execute.c
>>> index aea4b07..ee422e7 100644
>>> --- a/src/mesa/shader/prog_execute.c
>>> +++ b/src/mesa/shader/prog_execute.c
>>> @@ -1780,15 +1780,10 @@ _mesa_execute_program(GLcontext * ctx,
>>>           break;
>>>        case OPCODE_PRINT:
>>>           {
>>> -            if (inst->SrcReg[0].File != -1) {
>>> -               GLfloat a[4];
>>> -               fetch_vector4(&inst->SrcReg[0], machine, a);
>>> -               _mesa_printf("%s%g, %g, %g, %g\n", (const char *) inst-
>>> Data,
>>> -                            a[0], a[1], a[2], a[3]);
>>> -            }
>>> -            else {
>>> -               _mesa_printf("%s\n", (const char *) inst->Data);
>>> -            }
>>> +            GLfloat a[4];
>>> +            fetch_vector4(&inst->SrcReg[0], machine, a);
>>> +            _mesa_printf("%s%g, %g, %g, %g\n", (const char *) inst-
>>> Data,
>>> +                         a[0], a[1], a[2], a[3]);
>> I don't think this is correct.  The shader assembler used to set the
>> register file to -1 to note the difference between the following two
>> instructions:
>>
>> 	PRINT	"Hello, world";
>> 	PRINT	"vertex color", color;
>>
>> Even if comparing with -1 isn't entirely correct, removing the code
>> altogether is clearly wrong.
>>
>>>           }
>>>           break;
>>>        case OPCODE_END:
> 
> Where is the set of the register file to -1?

At nvvertparse.c:1099 it's set to zero.  I don't see where it's set to 
-1 either.


> Should the -1 comparison been against PROGRAM_FILE_MAX or PROGRAM_UNDEFINED instead?

The assignment above should probably use PROGRAM_UNDEFINED instead of 0.

-Brian