brw_clip_line.c File Reference

Include dependency graph for brw_clip_line.c:

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Functions
static void	brw_clip_line_alloc_regs (struct brw_clip_compile *c)
static void	clip_and_emit_line (struct brw_clip_compile *c)
void	brw_emit_line_clip (struct brw_clip_compile *c)

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Function Documentation

static void brw_clip_line_alloc_regs

(

struct brw_clip_compile *

c

)

[static]

Definition at line 40 of file brw_clip_line.c.

References BRW_REGISTER_TYPE_UD, brw_vec1_grf(), brw_vec4_grf(), brw_vec8_grf(), brw_clip_prog_data::curb_read_length, brw_clip_compile::dp1, brw_clip_compile::first_tmp, brw_clip_compile::fixed_planes, brw_clip_compile::key, brw_clip_compile::last_tmp, brw_clip_compile::nr_regs, brw_clip_prog_key::nr_userclip, brw_clip_compile::plane_equation, brw_clip_compile::planemask, brw_clip_compile::prog_data, brw_clip_compile::R0, brw_clip_compile::reg, retype(), brw_clip_compile::t, brw_clip_compile::t1, brw_clip_prog_data::total_grf, brw_clip_prog_data::urb_read_length, and brw_clip_compile::vertex.

{
   unsigned i = 0,j;

   /* Register usage is static, precompute here:
    */
   c->reg.R0 = retype(brw_vec8_grf(i, 0), BRW_REGISTER_TYPE_UD); i++;

   if (c->key.nr_userclip) {
      c->reg.fixed_planes = brw_vec4_grf(i, 0);
      i += (6 + c->key.nr_userclip + 1) / 2;

      c->prog_data.curb_read_length = (6 + c->key.nr_userclip + 1) / 2;
   }
   else
      c->prog_data.curb_read_length = 0;


   /* Payload vertices plus space for more generated vertices:
    */
   for (j = 0; j < 4; j++) {
      c->reg.vertex[j] = brw_vec4_grf(i, 0);
      i += c->nr_regs;
   }

   c->reg.t           = brw_vec1_grf(i, 0);
   c->reg.t0          = brw_vec1_grf(i, 1);
   c->reg.t1          = brw_vec1_grf(i, 2);
   c->reg.planemask   = retype(brw_vec1_grf(i, 3), BRW_REGISTER_TYPE_UD);
   c->reg.plane_equation = brw_vec4_grf(i, 4);
   i++;

   c->reg.dp0         = brw_vec1_grf(i, 0); /* fixme - dp4 will clobber r.1,2,3 */
   c->reg.dp1         = brw_vec1_grf(i, 4);
   i++;

   if (!c->key.nr_userclip) {
      c->reg.fixed_planes = brw_vec8_grf(i, 0);
      i++;
   }


   c->first_tmp = i;
   c->last_tmp = i;

   c->prog_data.urb_read_length = c->nr_regs; /* ? */
   c->prog_data.total_grf = i;
}

void brw_emit_line_clip

(

struct brw_clip_compile *

c

)

Definition at line 237 of file brw_clip_line.c.

References brw_clip_copy_colors(), brw_clip_line_alloc_regs(), clip_and_emit_line(), brw_clip_prog_key::do_flat_shading, and brw_clip_compile::key.

{
   brw_clip_line_alloc_regs(c);

   if (c->key.do_flat_shading)
      brw_clip_copy_colors(c, 0, 1);

   clip_and_emit_line(c);
}

static void clip_and_emit_line

(

struct brw_clip_compile *

c

)

[static]

Definition at line 115 of file brw_clip_line.c.

References _3DPRIM_LINESTRIP, brw_ADD(), brw_address(), brw_AND(), brw_clip_emit_vue(), brw_clip_init_clipmask(), brw_clip_init_planes(), brw_clip_interp_vertex(), brw_clip_kill_thread(), brw_clip_plane0_address(), brw_clip_plane_stride(), brw_CMP(), BRW_CONDITIONAL_G, BRW_CONDITIONAL_L, BRW_CONDITIONAL_NZ, brw_DO(), brw_DP4(), brw_ELSE(), brw_ENDIF(), BRW_EXECUTE_1, brw_IF(), brw_imm_f(), brw_imm_ud(), brw_indirect(), brw_math_invert(), brw_MOV(), brw_MUL(), brw_null_reg(), brw_OR(), BRW_PREDICATE_NONE, BRW_REGISTER_TYPE_UD, brw_set_conditionalmod(), brw_set_predicate_control(), brw_SHR(), brw_WHILE(), deref_4b(), deref_4f(), brw_clip_compile::dp1, FALSE, brw_clip_compile::func, get_addr_reg(), get_element_ud(), brw_clip_compile::key, negate(), brw_clip_prog_key::nr_userclip, brw_clip_compile::offset, brw_clip_compile::plane_equation, brw_clip_compile::planemask, brw_clip_compile::R0, R02_PRIM_END, R02_PRIM_START, brw_clip_compile::reg, retype(), brw_clip_compile::t, brw_clip_compile::t1, vec1(), vec2(), vec4(), and brw_clip_compile::vertex.

{
   struct brw_compile *p = &c->func;
   struct brw_indirect vtx0     = brw_indirect(0, 0);
   struct brw_indirect vtx1      = brw_indirect(1, 0);
   struct brw_indirect newvtx0   = brw_indirect(2, 0);
   struct brw_indirect newvtx1   = brw_indirect(3, 0);
   struct brw_indirect plane_ptr = brw_indirect(4, 0);
   struct brw_instruction *plane_loop;
   struct brw_instruction *plane_active;
   struct brw_instruction *is_negative;
   struct brw_instruction *is_neg2;
   struct brw_instruction *not_culled;
   struct brw_reg v1_null_ud = retype(vec1(brw_null_reg()), BRW_REGISTER_TYPE_UD);

   brw_MOV(p, get_addr_reg(vtx0),      brw_address(c->reg.vertex[0]));
   brw_MOV(p, get_addr_reg(vtx1),      brw_address(c->reg.vertex[1]));
   brw_MOV(p, get_addr_reg(newvtx0),   brw_address(c->reg.vertex[2]));
   brw_MOV(p, get_addr_reg(newvtx1),   brw_address(c->reg.vertex[3]));
   brw_MOV(p, get_addr_reg(plane_ptr), brw_clip_plane0_address(c));

   /* Note: init t0, t1 together:
    */
   brw_MOV(p, vec2(c->reg.t0), brw_imm_f(0));

   brw_clip_init_planes(c);
   brw_clip_init_clipmask(c);

   /* -ve rhw workaround */
   brw_set_conditionalmod(p, BRW_CONDITIONAL_NZ);
   brw_AND(p, brw_null_reg(), get_element_ud(c->reg.R0, 2),
           brw_imm_ud(1<<20));
   brw_OR(p, c->reg.planemask, c->reg.planemask, brw_imm_ud(0x3f));
   brw_set_predicate_control(p, BRW_PREDICATE_NONE);

   plane_loop = brw_DO(p, BRW_EXECUTE_1);
   {
      /* if (planemask & 1)
       */
      brw_set_conditionalmod(p, BRW_CONDITIONAL_NZ);
      brw_AND(p, v1_null_ud, c->reg.planemask, brw_imm_ud(1));

      plane_active = brw_IF(p, BRW_EXECUTE_1);
      {
         if (c->key.nr_userclip)
            brw_MOV(p, c->reg.plane_equation, deref_4f(plane_ptr, 0));
         else
            brw_MOV(p, c->reg.plane_equation, deref_4b(plane_ptr, 0));

#if 0
         /* dp = DP4(vtx->position, plane)
          */
         brw_DP4(p, vec4(c->reg.dp0), deref_4f(vtx0, c->offset[VERT_RESULT_HPOS]), c->reg.plane_equation);

         /* if (IS_NEGATIVE(dp1))
          */
         brw_set_conditionalmod(p, BRW_CONDITIONAL_L);
         brw_DP4(p, vec4(c->reg.dp1), deref_4f(vtx1, c->offset[VERT_RESULT_HPOS]), c->reg.plane_equation);
#else
         #warning "disabled"
#endif
         is_negative = brw_IF(p, BRW_EXECUTE_1);
         {
            brw_ADD(p, c->reg.t, c->reg.dp1, negate(c->reg.dp0));
            brw_math_invert(p, c->reg.t, c->reg.t);
            brw_MUL(p, c->reg.t, c->reg.t, c->reg.dp1);

            brw_CMP(p, vec1(brw_null_reg()), BRW_CONDITIONAL_G, c->reg.t, c->reg.t1 );
            brw_MOV(p, c->reg.t1, c->reg.t);
            brw_set_predicate_control(p, BRW_PREDICATE_NONE);
         }
         is_negative = brw_ELSE(p, is_negative);
         {
            /* Coming back in.  We know that both cannot be negative
             * because the line would have been culled in that case.
             */

            /* If both are positive, do nothing */
             brw_CMP(p, vec1(brw_null_reg()), BRW_CONDITIONAL_L, c->reg.dp0, brw_imm_f(0.0));
             is_neg2 = brw_IF(p, BRW_EXECUTE_1);
             {
                brw_ADD(p, c->reg.t, c->reg.dp0, negate(c->reg.dp1));
                brw_math_invert(p, c->reg.t, c->reg.t);
                brw_MUL(p, c->reg.t, c->reg.t, c->reg.dp0);

                brw_CMP(p, vec1(brw_null_reg()), BRW_CONDITIONAL_G, c->reg.t, c->reg.t0 );
                brw_MOV(p, c->reg.t0, c->reg.t);
                brw_set_predicate_control(p, BRW_PREDICATE_NONE);
             }
             brw_ENDIF(p, is_neg2);
         }
         brw_ENDIF(p, is_negative);
      }
      brw_ENDIF(p, plane_active);

      /* plane_ptr++;
       */
      brw_ADD(p, get_addr_reg(plane_ptr), get_addr_reg(plane_ptr), brw_clip_plane_stride(c));

      /* while (planemask>>=1) != 0
       */
      brw_set_conditionalmod(p, BRW_CONDITIONAL_NZ);
      brw_SHR(p, c->reg.planemask, c->reg.planemask, brw_imm_ud(1));
   }
   brw_WHILE(p, plane_loop);

   brw_ADD(p, c->reg.t, c->reg.t0, c->reg.t1);
   brw_CMP(p, vec1(brw_null_reg()), BRW_CONDITIONAL_L, c->reg.t, brw_imm_f(1.0));
   not_culled = brw_IF(p, BRW_EXECUTE_1);
   {
      brw_clip_interp_vertex(c, newvtx0, vtx0, vtx1, c->reg.t0, FALSE);
      brw_clip_interp_vertex(c, newvtx1, vtx1, vtx0, c->reg.t1, FALSE);

      brw_clip_emit_vue(c, newvtx0, 1, 0, (_3DPRIM_LINESTRIP << 2) | R02_PRIM_START);
      brw_clip_emit_vue(c, newvtx1, 0, 1, (_3DPRIM_LINESTRIP << 2) | R02_PRIM_END);
   }
   brw_ENDIF(p, not_culled);
   brw_clip_kill_thread(c);
}

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