[PATCH 1/2] nv40: don't crash on empty fragment program

[PATCH 1/2] nv40: don't crash on empty fragment program

[Luca Barbieri]

---
 src/gallium/drivers/nv40/nv40_fragprog.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/src/gallium/drivers/nv40/nv40_fragprog.c b/src/gallium/drivers/nv40/nv40_fragprog.c
index 1237066..209d211 100644
--- a/src/gallium/drivers/nv40/nv40_fragprog.c
+++ b/src/gallium/drivers/nv40/nv40_fragprog.c
@@ -843,7 +843,8 @@ nv40_fragprog_translate(struct nv40_context *nv40,
 	fp->fp_control |= fpc->num_regs << NV40TCL_FP_CONTROL_TEMP_COUNT_SHIFT;
 
 	/* Terminate final instruction */
-	fp->insn[fpc->inst_offset] |= 0x00000001;
+	if(fp->insn)
+                fp->insn[fpc->inst_offset] |= 0x00000001;
 
 	/* Append NOP + END instruction, may or may not be necessary. */
 	fpc->inst_offset = fp->insn_len;
-- 
1.6.3.3

[PATCH 2/2] st: don't assert on empty fragment program

[Luca Barbieri]

Sauerbraten triggers this assert.
---
 src/mesa/state_tracker/st_atom_shader.c |    2 --
 1 files changed, 0 insertions(+), 2 deletions(-)

diff --git a/src/mesa/state_tracker/st_atom_shader.c b/src/mesa/state_tracker/st_atom_shader.c
index 176f3ea..fce533a 100644
--- a/src/mesa/state_tracker/st_atom_shader.c
+++ b/src/mesa/state_tracker/st_atom_shader.c
@@ -79,8 +79,6 @@ translate_fp(struct st_context *st,
 
       stfp->num_input_slots = numIn;
 
-      assert(stfp->Base.Base.NumInstructions > 1);
-
       st_translate_fragment_program(st, stfp, stfp->input_to_slot);
    }
 }
-- 
1.6.3.3

Re: [PATCH 2/2] st: don't assert on empty fragment program

[Brian Paul]

Luca Barbieri wrote:
> Sauerbraten triggers this assert.
> ---
>  src/mesa/state_tracker/st_atom_shader.c |    2 --
>  1 files changed, 0 insertions(+), 2 deletions(-)
> 
> diff --git a/src/mesa/state_tracker/st_atom_shader.c b/src/mesa/state_tracker/st_atom_shader.c
> index 176f3ea..fce533a 100644
> --- a/src/mesa/state_tracker/st_atom_shader.c
> +++ b/src/mesa/state_tracker/st_atom_shader.c
> @@ -79,8 +79,6 @@ translate_fp(struct st_context *st,
>  
>        stfp->num_input_slots = numIn;
>  
> -      assert(stfp->Base.Base.NumInstructions > 1);
> -
>        st_translate_fragment_program(st, stfp, stfp->input_to_slot);
>     }
>  }

How do we end up with a shader that has only one instruction (or 
none)?  Is it an END instruction?  I'd like to learn more about what's 
happening before committing this.

-Brian


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Re: [Mesa3d-dev] [PATCH 2/2] st: don't assert on empty fragment program

[Luca Barbieri]

Breakpoint 3, _mesa_ProgramStringARB (target=34820, format=34933,
len=70, string=0x85922ba) at shader/arbprogram.c:434
434	   GET_CURRENT_CONTEXT(ctx);
$31 = 0x85922ba "!!ARBfp1.0\n    \n    OPTION
ARB_precision_hint_fastest;\n    \n\n\n    END\n"

Not sure why Sauerbraten does this, but it does, at least on my system
(Ubuntu Karmic, nv40 driver) and it should be legal.

Re: [PATCH 2/2] st: don't assert on empty fragment program

[Brian Paul]

Luca Barbieri wrote:
> Breakpoint 3, _mesa_ProgramStringARB (target=34820, format=34933,
> len=70, string=0x85922ba) at shader/arbprogram.c:434
> 434	   GET_CURRENT_CONTEXT(ctx);
> $31 = 0x85922ba "!!ARBfp1.0\n    \n    OPTION
> ARB_precision_hint_fastest;\n    \n\n\n    END\n"
> 
> Not sure why Sauerbraten does this, but it does, at least on my system
> (Ubuntu Karmic, nv40 driver) and it should be legal.

OK, GL_ARB_fragment_programs says a fragment program does not have to 
write a color result (so the color is undefined).

But the assertion should be changed to "num instructions > 0" and not 
removed.  I'll fix that.

-Brian


------------------------------------------------------------------------------
Throughout its 18-year history, RSA Conference consistently attracts the
world's best and brightest in the field, creating opportunities for Conference
attendees to learn about information security's most important issues through
interactions with peers, luminaries and emerging and established companies.
http://p.sf.net/sfu/rsaconf-dev2dev

Re: [PATCH 2/2] st: don't assert on empty fragment program

[Roland Scheidegger]

On 18.01.2010 19:15, Luca Barbieri wrote:
> Breakpoint 3, _mesa_ProgramStringARB (target=34820, format=34933,
> len=70, string=0x85922ba) at shader/arbprogram.c:434
> 434	   GET_CURRENT_CONTEXT(ctx);
> $31 = 0x85922ba "!!ARBfp1.0\n    \n    OPTION
> ARB_precision_hint_fastest;\n    \n\n\n    END\n"
> 
> Not sure why Sauerbraten does this, but it does, at least on my system
> (Ubuntu Karmic, nv40 driver) and it should be legal.

Probably depth writes only enabled for things like shadows?

Roland

------------------------------------------------------------------------------
Throughout its 18-year history, RSA Conference consistently attracts the
world's best and brightest in the field, creating opportunities for Conference
attendees to learn about information security's most important issues through
interactions with peers, luminaries and emerging and established companies.
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Re: [Mesa3d-dev] [PATCH 2/2] st: don't assert on empty fragment program

[Luca Barbieri]

> But the assertion should be changed to "num instructions > 0" and not
> removed.  I'll fix that.

OK.
Programs without END should be rejected by the parser anyway though.