i915_fragprog.c

Mesa is an open-source implementation of the OpenGL specification - a system for rendering interacti

	  */

	 /* tmp.y = abs(tmp.x); {x, abs(x), 0, 0} */
	 i915_emit_arith(p,
                         A0_MAX,
			 tmp, A0_DEST_CHANNEL_Y, 0,
			 swizzle(tmp, ZERO, X, ZERO, ZERO),
			 negate(swizzle(tmp, ZERO, X, ZERO, ZERO), 0, 1, 0, 0),
			 0);

	 /* tmp.y = tmp.y * tmp.x; {x, x * abs(x), 0, 0} */
	 i915_emit_arith(p,
			 A0_MUL,
			 tmp, A0_DEST_CHANNEL_Y, 0,
			 swizzle(tmp, ZERO, X, ZERO, ZERO),
			 tmp,
			 0);

	 /* tmp.x = tmp.xy DP sin_quad_constants[2].xy */
         i915_emit_arith(p,
                         A0_DP3,
                         tmp, A0_DEST_CHANNEL_X, 0,
			 tmp,
                         swizzle(consts1, X, Y, ZERO, ZERO),
			 0);

	 /* tmp.x now contains a first approximation (y).  Now, weight it
	  * against tmp.y**2 to get closer.
	  */
	 i915_emit_arith(p,
                         A0_MAX,
			 tmp, A0_DEST_CHANNEL_Y, 0,
			 swizzle(tmp, ZERO, X, ZERO, ZERO),
			 negate(swizzle(tmp, ZERO, X, ZERO, ZERO), 0, 1, 0, 0),
			 0);

	 /* tmp.y = tmp.x * tmp.y - tmp.x; {y, y * abs(y) - y, 0, 0} */
	 i915_emit_arith(p,
			 A0_MAD,
			 tmp, A0_DEST_CHANNEL_Y, 0,
			 swizzle(tmp, ZERO, X, ZERO, ZERO),
			 swizzle(tmp, ZERO, Y, ZERO, ZERO),
			 negate(swizzle(tmp, ZERO, X, ZERO, ZERO), 0, 1, 0, 0));

	 /* result = .2225 * tmp.y + tmp.x =.2225(y * abs(y) - y) + y= */
	 i915_emit_arith(p,
			 A0_MAD,
                         get_result_vector(p, inst),
                         get_result_flags(inst), 0,
			 swizzle(consts1, W, W, W, W),
			 swizzle(tmp, Y, Y, Y, Y),
			 swizzle(tmp, X, X, X, X));
         break;

      case OPCODE_DP3:
         EMIT_2ARG_ARITH(A0_DP3);
         break;

      case OPCODE_DP4:
         EMIT_2ARG_ARITH(A0_DP4);
         break;

      case OPCODE_DPH:
         src0 = src_vector(p, &inst->SrcReg[0], program);
         src1 = src_vector(p, &inst->SrcReg[1], program);

         i915_emit_arith(p,
                         A0_DP4,
                         get_result_vector(p, inst),
                         get_result_flags(inst), 0,
                         swizzle(src0, X, Y, Z, ONE), src1, 0);
         break;

      case OPCODE_DST:
         src0 = src_vector(p, &inst->SrcReg[0], program);
         src1 = src_vector(p, &inst->SrcReg[1], program);

         /* result[0] = 1    * 1;
          * result[1] = a[1] * b[1];
          * result[2] = a[2] * 1;
          * result[3] = 1    * b[3];
          */
         i915_emit_arith(p,
                         A0_MUL,
                         get_result_vector(p, inst),
                         get_result_flags(inst), 0,
                         swizzle(src0, ONE, Y, Z, ONE),
                         swizzle(src1, ONE, Y, ONE, W), 0);
         break;

      case OPCODE_EX2:
         src0 = src_vector(p, &inst->SrcReg[0], program);

         i915_emit_arith(p,
                         A0_EXP,
                         get_result_vector(p, inst),
                         get_result_flags(inst), 0,
                         swizzle(src0, X, X, X, X), 0, 0);
         break;

      case OPCODE_FLR:
         EMIT_1ARG_ARITH(A0_FLR);
         break;

      case OPCODE_FRC:
         EMIT_1ARG_ARITH(A0_FRC);
         break;

      case OPCODE_KIL:
         src0 = src_vector(p, &inst->SrcReg[0], program);
         tmp = i915_get_utemp(p);

         i915_emit_texld(p, get_live_regs(p, inst),
                         tmp, A0_DEST_CHANNEL_ALL,   /* use a dummy dest reg */
                         0, src0, T0_TEXKILL);
         break;

      case OPCODE_LG2:
         src0 = src_vector(p, &inst->SrcReg[0], program);

         i915_emit_arith(p,
                         A0_LOG,
                         get_result_vector(p, inst),
                         get_result_flags(inst), 0,
                         swizzle(src0, X, X, X, X), 0, 0);
         break;

      case OPCODE_LIT:
         src0 = src_vector(p, &inst->SrcReg[0], program);
         tmp = i915_get_utemp(p);

         /* tmp = max( a.xyzw, a.00zw )
          * XXX: Clamp tmp.w to -128..128
          * tmp.y = log(tmp.y)
          * tmp.y = tmp.w * tmp.y
          * tmp.y = exp(tmp.y)
          * result = cmp (a.11-x1, a.1x01, a.1xy1 )
          */
         i915_emit_arith(p, A0_MAX, tmp, A0_DEST_CHANNEL_ALL, 0,
                         src0, swizzle(src0, ZERO, ZERO, Z, W), 0);

         i915_emit_arith(p, A0_LOG, tmp, A0_DEST_CHANNEL_Y, 0,
                         swizzle(tmp, Y, Y, Y, Y), 0, 0);

         i915_emit_arith(p, A0_MUL, tmp, A0_DEST_CHANNEL_Y, 0,
                         swizzle(tmp, ZERO, Y, ZERO, ZERO),
                         swizzle(tmp, ZERO, W, ZERO, ZERO), 0);

         i915_emit_arith(p, A0_EXP, tmp, A0_DEST_CHANNEL_Y, 0,
                         swizzle(tmp, Y, Y, Y, Y), 0, 0);

         i915_emit_arith(p, A0_CMP,
                         get_result_vector(p, inst),
                         get_result_flags(inst), 0,
                         negate(swizzle(tmp, ONE, ONE, X, ONE), 0, 0, 1, 0),
                         swizzle(tmp, ONE, X, ZERO, ONE),
                         swizzle(tmp, ONE, X, Y, ONE));

         break;

      case OPCODE_LRP:
         src0 = src_vector(p, &inst->SrcReg[0], program);
         src1 = src_vector(p, &inst->SrcReg[1], program);
         src2 = src_vector(p, &inst->SrcReg[2], program);
         flags = get_result_flags(inst);
         tmp = i915_get_utemp(p);

         /* b*a + c*(1-a)
          *
          * b*a + c - ca 
          *
          * tmp = b*a + c, 
          * result = (-c)*a + tmp 
          */
         i915_emit_arith(p, A0_MAD, tmp,
                         flags & A0_DEST_CHANNEL_ALL, 0, src1, src0, src2);

         i915_emit_arith(p, A0_MAD,
                         get_result_vector(p, inst),
                         flags, 0, negate(src2, 1, 1, 1, 1), src0, tmp);
         break;

      case OPCODE_MAD:
         EMIT_3ARG_ARITH(A0_MAD);
         break;

      case OPCODE_MAX:
         EMIT_2ARG_ARITH(A0_MAX);
         break;

      case OPCODE_MIN:
         src0 = src_vector(p, &inst->SrcReg[0], program);
         src1 = src_vector(p, &inst->SrcReg[1], program);
         tmp = i915_get_utemp(p);
         flags = get_result_flags(inst);

         i915_emit_arith(p,
                         A0_MAX,
                         tmp, flags & A0_DEST_CHANNEL_ALL, 0,
                         negate(src0, 1, 1, 1, 1),
                         negate(src1, 1, 1, 1, 1), 0);

         i915_emit_arith(p,
                         A0_MOV,
                         get_result_vector(p, inst),
                         flags, 0, negate(tmp, 1, 1, 1, 1), 0, 0);
         break;

      case OPCODE_MOV:
         EMIT_1ARG_ARITH(A0_MOV);
         break;

      case OPCODE_MUL:
         EMIT_2ARG_ARITH(A0_MUL);
         break;

      case OPCODE_POW:
         src0 = src_vector(p, &inst->SrcReg[0], program);
         src1 = src_vector(p, &inst->SrcReg[1], program);
         tmp = i915_get_utemp(p);
         flags = get_result_flags(inst);

         /* XXX: masking on intermediate values, here and elsewhere.
          */
         i915_emit_arith(p,
                         A0_LOG,
                         tmp, A0_DEST_CHANNEL_X, 0,
                         swizzle(src0, X, X, X, X), 0, 0);

         i915_emit_arith(p, A0_MUL, tmp, A0_DEST_CHANNEL_X, 0, tmp, src1, 0);


         i915_emit_arith(p,
                         A0_EXP,
                         get_result_vector(p, inst),
                         flags, 0, swizzle(tmp, X, X, X, X), 0, 0);

         break;

      case OPCODE_RCP:
         src0 = src_vector(p, &inst->SrcReg[0], program);

         i915_emit_arith(p,
                         A0_RCP,
                         get_result_vector(p, inst),
                         get_result_flags(inst), 0,
                         swizzle(src0, X, X, X, X), 0, 0);
         break;

      case OPCODE_RSQ:

         src0 = src_vector(p, &inst->SrcReg[0], program);

         i915_emit_arith(p,
                         A0_RSQ,
                         get_result_vector(p, inst),
                         get_result_flags(inst), 0,
                         swizzle(src0, X, X, X, X), 0, 0);
         break;

      case OPCODE_SCS:
         src0 = src_vector(p, &inst->SrcReg[0], program);
         tmp = i915_get_utemp(p);

         /* 
          * t0.xy = MUL x.xx11, x.x1111  ; x^2, x, 1, 1
          * t0 = MUL t0.xyxy t0.xx11 ; x^4, x^3, x^2, x
          * t1 = MUL t0.xyyw t0.yz11    ; x^7 x^5 x^3 x
          * scs.x = DP4 t1, sin_constants
          * t1 = MUL t0.xxz1 t0.z111    ; x^6 x^4 x^2 1
          * scs.y = DP4 t1, cos_constants
          */
         i915_emit_arith(p,
                         A0_MUL,
                         tmp, A0_DEST_CHANNEL_XY, 0,
                         swizzle(src0, X, X, ONE, ONE),
                         swizzle(src0, X, ONE, ONE, ONE), 0);

         i915_emit_arith(p,
                         A0_MUL,
                         tmp, A0_DEST_CHANNEL_ALL, 0,
                         swizzle(tmp, X, Y, X, Y),
                         swizzle(tmp, X, X, ONE, ONE), 0);

         if (inst->DstReg.WriteMask & WRITEMASK_Y) {
            GLuint tmp1;

            if (inst->DstReg.WriteMask & WRITEMASK_X)
               tmp1 = i915_get_utemp(p);
            else
               tmp1 = tmp;

            i915_emit_arith(p,
                            A0_MUL,
                            tmp1, A0_DEST_CHANNEL_ALL, 0,
                            swizzle(tmp, X, Y, Y, W),
                            swizzle(tmp, X, Z, ONE, ONE), 0);

            i915_emit_arith(p,
                            A0_DP4,
                            get_result_vector(p, inst),
                            A0_DEST_CHANNEL_Y, 0,
                            swizzle(tmp1, W, Z, Y, X),
                            i915_emit_const4fv(p, sin_constants), 0);
         }

         if (inst->DstReg.WriteMask & WRITEMASK_X) {
            i915_emit_arith(p,
                            A0_MUL,
                            tmp, A0_DEST_CHANNEL_XYZ, 0,
                            swizzle(tmp, X, X, Z, ONE),
                            swizzle(tmp, Z, ONE, ONE, ONE), 0);

            i915_emit_arith(p,
                            A0_DP4,
                            get_result_vector(p, inst),
                            A0_DEST_CHANNEL_X, 0,
                            swizzle(tmp, ONE, Z, Y, X),
                            i915_emit_const4fv(p, cos_constants), 0);
         }
         break;

      case OPCODE_SGE:
         EMIT_2ARG_ARITH(A0_SGE);
         break;

      case OPCODE_SIN:
         src0 = src_vector(p, &inst->SrcReg[0], program);
         tmp = i915_get_utemp(p);
	 consts0 = i915_emit_const4fv(p, sin_quad_constants[0]);
	 consts1 = i915_emit_const4fv(p, sin_quad_constants[1]);

	 /* Reduce range from repeating about [-pi,pi] to [-1,1] */
         i915_emit_arith(p,
                         A0_MAD,
                         tmp, A0_DEST_CHANNEL_X, 0,
                         src0,
			 swizzle(consts1, Z, ZERO, ZERO, ZERO), /* 1/(2pi) */
			 swizzle(consts0, Z, ZERO, ZERO, ZERO)); /* .5 */

         i915_emit_arith(p, A0_FRC, tmp, A0_DEST_CHANNEL_X, 0, tmp, 0, 0);

	 i915_emit_arith(p,
			 A0_MAD,
			 tmp, A0_DEST_CHANNEL_X, 0,
			 tmp,
			 swizzle(consts0, X, ZERO, ZERO, ZERO), /* 2 */
			 swizzle(consts0, Y, ZERO, ZERO, ZERO)); /* -1 */

	 /* Compute sin using a quadratic and quartic.  It gives continuity
	  * that repeating the Taylor series lacks every 2*pi, and has
	  * reduced error.
	  *
	  * The idea was described at:
	  * http://www.devmaster.net/forums/showthread.php?t=5784
	  */

	 /* tmp.y = abs(tmp.x); {x, abs(x), 0, 0} */
	 i915_emit_arith(p,
                         A0_MAX,
			 tmp, A0_DEST_CHANNEL_Y, 0,
			 swizzle(tmp, ZERO, X, ZERO, ZERO),
			 negate(swizzle(tmp, ZERO, X, ZERO, ZERO), 0, 1, 0, 0),
			 0);

	 /* tmp.y = tmp.y * tmp.x; {x, x * abs(x), 0, 0} */
	 i915_emit_arith(p,
			 A0_MUL,
			 tmp, A0_DEST_CHANNEL_Y, 0,
			 swizzle(tmp, ZERO, X, ZERO, ZERO),
			 tmp,
			 0);

	 /* tmp.x = tmp.xy DP sin_quad_constants[2].xy */
         i915_emit_arith(p,
                         A0_DP3,
                         tmp, A0_DEST_CHANNEL_X, 0,
			 tmp,
                         swizzle(consts1, X, Y, ZERO, ZERO),
			 0);

	 /* tmp.x now contains a first approximation (y).  Now, weight it
	  * against tmp.y**2 to get closer.
	  */
	 i915_emit_arith(p,
                         A0_MAX,
			 tmp, A0_DEST_CHANNEL_Y, 0,
			 swizzle(tmp, ZERO, X, ZERO, ZERO),
			 negate(swizzle(tmp, ZERO, X, ZERO, ZERO), 0, 1, 0, 0),
			 0);

	 /* tmp.y = tmp.x * tmp.y - tmp.x; {y, y * abs(y) - y, 0, 0} */
	 i915_emit_arith(p,
			 A0_MAD,
			 tmp, A0_DEST_CHANNEL_Y, 0,
			 swizzle(tmp, ZERO, X, ZERO, ZERO),
			 swizzle(tmp, ZERO, Y, ZERO, ZERO),
			 negate(swizzle(tmp, ZERO, X, ZERO, ZERO), 0, 1, 0, 0));