mesa pixman git update 5 aug 2011

1 files changed, 1895 insertions, 1895 deletions

diff --git a/mesalib/src/mesa/program/prog_execute.c b/mesalib/src/mesa/program/prog_execute.c
index 28a3e1e20..dbfd1b918 100644
--- a/mesalib/src/mesa/program/prog_execute.c
+++ b/mesalib/src/mesa/program/prog_execute.c
@@ -1,1895 +1,1895 @@
-/*

- * Mesa 3-D graphics library

- * Version:  7.3

- *

- * Copyright (C) 1999-2008  Brian Paul   All Rights Reserved.

- *

- * Permission is hereby granted, free of charge, to any person obtaining a

- * copy of this software and associated documentation files (the "Software"),

- * to deal in the Software without restriction, including without limitation

- * the rights to use, copy, modify, merge, publish, distribute, sublicense,

- * and/or sell copies of the Software, and to permit persons to whom the

- * Software is furnished to do so, subject to the following conditions:

- *

- * The above copyright notice and this permission notice shall be included

- * in all copies or substantial portions of the Software.

- *

- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS

- * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL

- * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN

- * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN

- * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

- */

-

-/**

- * \file prog_execute.c

- * Software interpreter for vertex/fragment programs.

- * \author Brian Paul

- */

-

-/*

- * NOTE: we do everything in single-precision floating point; we don't

- * currently observe the single/half/fixed-precision qualifiers.

- *

- */

-

-

-#include "main/glheader.h"

-#include "main/colormac.h"

-#include "main/macros.h"

-#include "prog_execute.h"

-#include "prog_instruction.h"

-#include "prog_parameter.h"

-#include "prog_print.h"

-#include "prog_noise.h"

-

-

-/* debug predicate */

-#define DEBUG_PROG 0

-

-

-/**

- * Set x to positive or negative infinity.

- */

-#if defined(USE_IEEE) || defined(_WIN32)

-#define SET_POS_INFINITY(x)                  \

-   do {                                      \

-         fi_type fi;                         \

-         fi.i = 0x7F800000;                  \

-         x = fi.f;                           \

-   } while (0)

-#define SET_NEG_INFINITY(x)                  \

-   do {                                      \

-         fi_type fi;                         \

-         fi.i = 0xFF800000;                  \

-         x = fi.f;                           \

-   } while (0)

-#elif defined(VMS)

-#define SET_POS_INFINITY(x)  x = __MAXFLOAT

-#define SET_NEG_INFINITY(x)  x = -__MAXFLOAT

-#else

-#define SET_POS_INFINITY(x)  x = (GLfloat) HUGE_VAL

-#define SET_NEG_INFINITY(x)  x = (GLfloat) -HUGE_VAL

-#endif

-

-#define SET_FLOAT_BITS(x, bits) ((fi_type *) (void *) &(x))->i = bits

-

-

-static const GLfloat ZeroVec[4] = { 0.0F, 0.0F, 0.0F, 0.0F };

-

-

-

-/**

- * Return TRUE for +0 and other positive values, FALSE otherwise.

- * Used for RCC opcode.

- */

-static INLINE GLboolean

-positive(float x)

-{

-   fi_type fi;

-   fi.f = x;

-   if (fi.i & 0x80000000)

-      return GL_FALSE;

-   return GL_TRUE;

-}

-

-

-

-/**

- * Return a pointer to the 4-element float vector specified by the given

- * source register.

- */

-static INLINE const GLfloat *

-get_src_register_pointer(const struct prog_src_register *source,

-                         const struct gl_program_machine *machine)

-{

-   const struct gl_program *prog = machine->CurProgram;

-   GLint reg = source->Index;

-

-   if (source->RelAddr) {

-      /* add address register value to src index/offset */

-      reg += machine->AddressReg[0][0];

-      if (reg < 0) {

-         return ZeroVec;

-      }

-   }

-

-   switch (source->File) {

-   case PROGRAM_TEMPORARY:

-      if (reg >= MAX_PROGRAM_TEMPS)

-         return ZeroVec;

-      return machine->Temporaries[reg];

-

-   case PROGRAM_INPUT:

-      if (prog->Target == GL_VERTEX_PROGRAM_ARB) {

-         if (reg >= VERT_ATTRIB_MAX)

-            return ZeroVec;

-         return machine->VertAttribs[reg];

-      }

-      else {

-         if (reg >= FRAG_ATTRIB_MAX)

-            return ZeroVec;

-         return machine->Attribs[reg][machine->CurElement];

-      }

-

-   case PROGRAM_OUTPUT:

-      if (reg >= MAX_PROGRAM_OUTPUTS)

-         return ZeroVec;

-      return machine->Outputs[reg];

-

-   case PROGRAM_LOCAL_PARAM:

-      if (reg >= MAX_PROGRAM_LOCAL_PARAMS)

-         return ZeroVec;

-      return machine->CurProgram->LocalParams[reg];

-

-   case PROGRAM_ENV_PARAM:

-      if (reg >= MAX_PROGRAM_ENV_PARAMS)

-         return ZeroVec;

-      return machine->EnvParams[reg];

-

-   case PROGRAM_STATE_VAR:

-      /* Fallthrough */

-   case PROGRAM_CONSTANT:

-      /* Fallthrough */

-   case PROGRAM_UNIFORM:

-      /* Fallthrough */

-   case PROGRAM_NAMED_PARAM:

-      if (reg >= (GLint) prog->Parameters->NumParameters)

-         return ZeroVec;

-      return prog->Parameters->ParameterValues[reg];

-

-   case PROGRAM_SYSTEM_VALUE:

-      assert(reg < Elements(machine->SystemValues));

-      return machine->SystemValues[reg];

-

-   default:

-      _mesa_problem(NULL,

-         "Invalid src register file %d in get_src_register_pointer()",

-         source->File);

-      return NULL;

-   }

-}

-

-

-/**

- * Return a pointer to the 4-element float vector specified by the given

- * destination register.

- */

-static INLINE GLfloat *

-get_dst_register_pointer(const struct prog_dst_register *dest,

-                         struct gl_program_machine *machine)

-{

-   static GLfloat dummyReg[4];

-   GLint reg = dest->Index;

-

-   if (dest->RelAddr) {

-      /* add address register value to src index/offset */

-      reg += machine->AddressReg[0][0];

-      if (reg < 0) {

-         return dummyReg;

-      }

-   }

-

-   switch (dest->File) {

-   case PROGRAM_TEMPORARY:

-      if (reg >= MAX_PROGRAM_TEMPS)

-         return dummyReg;

-      return machine->Temporaries[reg];

-

-   case PROGRAM_OUTPUT:

-      if (reg >= MAX_PROGRAM_OUTPUTS)

-         return dummyReg;

-      return machine->Outputs[reg];

-

-   case PROGRAM_WRITE_ONLY:

-      return dummyReg;

-

-   default:

-      _mesa_problem(NULL,

-         "Invalid dest register file %d in get_dst_register_pointer()",

-         dest->File);

-      return NULL;

-   }

-}

-

-

-

-/**

- * Fetch a 4-element float vector from the given source register.

- * Apply swizzling and negating as needed.

- */

-static void

-fetch_vector4(const struct prog_src_register *source,

-              const struct gl_program_machine *machine, GLfloat result[4])

-{

-   const GLfloat *src = get_src_register_pointer(source, machine);

-   ASSERT(src);

-

-   if (source->Swizzle == SWIZZLE_NOOP) {

-      /* no swizzling */

-      COPY_4V(result, src);

-   }

-   else {

-      ASSERT(GET_SWZ(source->Swizzle, 0) <= 3);

-      ASSERT(GET_SWZ(source->Swizzle, 1) <= 3);

-      ASSERT(GET_SWZ(source->Swizzle, 2) <= 3);

-      ASSERT(GET_SWZ(source->Swizzle, 3) <= 3);

-      result[0] = src[GET_SWZ(source->Swizzle, 0)];

-      result[1] = src[GET_SWZ(source->Swizzle, 1)];

-      result[2] = src[GET_SWZ(source->Swizzle, 2)];

-      result[3] = src[GET_SWZ(source->Swizzle, 3)];

-   }

-

-   if (source->Abs) {

-      result[0] = FABSF(result[0]);

-      result[1] = FABSF(result[1]);

-      result[2] = FABSF(result[2]);

-      result[3] = FABSF(result[3]);

-   }

-   if (source->Negate) {

-      ASSERT(source->Negate == NEGATE_XYZW);

-      result[0] = -result[0];

-      result[1] = -result[1];

-      result[2] = -result[2];

-      result[3] = -result[3];

-   }

-

-#ifdef NAN_CHECK

-   assert(!IS_INF_OR_NAN(result[0]));

-   assert(!IS_INF_OR_NAN(result[0]));

-   assert(!IS_INF_OR_NAN(result[0]));

-   assert(!IS_INF_OR_NAN(result[0]));

-#endif

-}

-

-

-/**

- * Fetch a 4-element uint vector from the given source register.

- * Apply swizzling but not negation/abs.

- */

-static void

-fetch_vector4ui(const struct prog_src_register *source,

-                const struct gl_program_machine *machine, GLuint result[4])

-{

-   const GLuint *src = (GLuint *) get_src_register_pointer(source, machine);

-   ASSERT(src);

-

-   if (source->Swizzle == SWIZZLE_NOOP) {

-      /* no swizzling */

-      COPY_4V(result, src);

-   }

-   else {

-      ASSERT(GET_SWZ(source->Swizzle, 0) <= 3);

-      ASSERT(GET_SWZ(source->Swizzle, 1) <= 3);

-      ASSERT(GET_SWZ(source->Swizzle, 2) <= 3);

-      ASSERT(GET_SWZ(source->Swizzle, 3) <= 3);

-      result[0] = src[GET_SWZ(source->Swizzle, 0)];

-      result[1] = src[GET_SWZ(source->Swizzle, 1)];

-      result[2] = src[GET_SWZ(source->Swizzle, 2)];

-      result[3] = src[GET_SWZ(source->Swizzle, 3)];

-   }

-

-   /* Note: no Negate or Abs here */

-}

-

-

-

-/**

- * Fetch the derivative with respect to X or Y for the given register.

- * XXX this currently only works for fragment program input attribs.

- */

-static void

-fetch_vector4_deriv(struct gl_context * ctx,

-                    const struct prog_src_register *source,

-                    const struct gl_program_machine *machine,

-                    char xOrY, GLfloat result[4])

-{

-   if (source->File == PROGRAM_INPUT &&

-       source->Index < (GLint) machine->NumDeriv) {

-      const GLint col = machine->CurElement;

-      const GLfloat w = machine->Attribs[FRAG_ATTRIB_WPOS][col][3];

-      const GLfloat invQ = 1.0f / w;

-      GLfloat deriv[4];

-

-      if (xOrY == 'X') {

-         deriv[0] = machine->DerivX[source->Index][0] * invQ;

-         deriv[1] = machine->DerivX[source->Index][1] * invQ;

-         deriv[2] = machine->DerivX[source->Index][2] * invQ;

-         deriv[3] = machine->DerivX[source->Index][3] * invQ;

-      }

-      else {

-         deriv[0] = machine->DerivY[source->Index][0] * invQ;

-         deriv[1] = machine->DerivY[source->Index][1] * invQ;

-         deriv[2] = machine->DerivY[source->Index][2] * invQ;

-         deriv[3] = machine->DerivY[source->Index][3] * invQ;

-      }

-

-      result[0] = deriv[GET_SWZ(source->Swizzle, 0)];

-      result[1] = deriv[GET_SWZ(source->Swizzle, 1)];

-      result[2] = deriv[GET_SWZ(source->Swizzle, 2)];

-      result[3] = deriv[GET_SWZ(source->Swizzle, 3)];

-      

-      if (source->Abs) {

-         result[0] = FABSF(result[0]);

-         result[1] = FABSF(result[1]);

-         result[2] = FABSF(result[2]);

-         result[3] = FABSF(result[3]);

-      }

-      if (source->Negate) {

-         ASSERT(source->Negate == NEGATE_XYZW);

-         result[0] = -result[0];

-         result[1] = -result[1];

-         result[2] = -result[2];

-         result[3] = -result[3];

-      }

-   }

-   else {

-      ASSIGN_4V(result, 0.0, 0.0, 0.0, 0.0);

-   }

-}

-

-

-/**

- * As above, but only return result[0] element.

- */

-static void

-fetch_vector1(const struct prog_src_register *source,

-              const struct gl_program_machine *machine, GLfloat result[4])

-{

-   const GLfloat *src = get_src_register_pointer(source, machine);

-   ASSERT(src);

-

-   result[0] = src[GET_SWZ(source->Swizzle, 0)];

-

-   if (source->Abs) {

-      result[0] = FABSF(result[0]);

-   }

-   if (source->Negate) {

-      result[0] = -result[0];

-   }

-}

-

-

-static GLuint

-fetch_vector1ui(const struct prog_src_register *source,

-                const struct gl_program_machine *machine)

-{

-   const GLuint *src = (GLuint *) get_src_register_pointer(source, machine);

-   return src[GET_SWZ(source->Swizzle, 0)];

-}

-

-

-/**

- * Fetch texel from texture.  Use partial derivatives when possible.

- */

-static INLINE void

-fetch_texel(struct gl_context *ctx,

-            const struct gl_program_machine *machine,

-            const struct prog_instruction *inst,

-            const GLfloat texcoord[4], GLfloat lodBias,

-            GLfloat color[4])

-{

-   const GLuint unit = machine->Samplers[inst->TexSrcUnit];

-

-   /* Note: we only have the right derivatives for fragment input attribs.

-    */

-   if (machine->NumDeriv > 0 &&

-       inst->SrcReg[0].File == PROGRAM_INPUT &&

-       inst->SrcReg[0].Index == FRAG_ATTRIB_TEX0 + inst->TexSrcUnit) {

-      /* simple texture fetch for which we should have derivatives */

-      GLuint attr = inst->SrcReg[0].Index;

-      machine->FetchTexelDeriv(ctx, texcoord,

-                               machine->DerivX[attr],

-                               machine->DerivY[attr],

-                               lodBias, unit, color);

-   }

-   else {

-      machine->FetchTexelLod(ctx, texcoord, lodBias, unit, color);

-   }

-}

-

-

-/**

- * Test value against zero and return GT, LT, EQ or UN if NaN.

- */

-static INLINE GLuint

-generate_cc(float value)

-{

-   if (value != value)

-      return COND_UN;           /* NaN */

-   if (value > 0.0F)

-      return COND_GT;

-   if (value < 0.0F)

-      return COND_LT;

-   return COND_EQ;

-}

-

-

-/**

- * Test if the ccMaskRule is satisfied by the given condition code.

- * Used to mask destination writes according to the current condition code.

- */

-static INLINE GLboolean

-test_cc(GLuint condCode, GLuint ccMaskRule)

-{

-   switch (ccMaskRule) {

-   case COND_EQ: return (condCode == COND_EQ);

-   case COND_NE: return (condCode != COND_EQ);

-   case COND_LT: return (condCode == COND_LT);

-   case COND_GE: return (condCode == COND_GT || condCode == COND_EQ);

-   case COND_LE: return (condCode == COND_LT || condCode == COND_EQ);

-   case COND_GT: return (condCode == COND_GT);

-   case COND_TR: return GL_TRUE;

-   case COND_FL: return GL_FALSE;

-   default:      return GL_TRUE;

-   }

-}

-

-

-/**

- * Evaluate the 4 condition codes against a predicate and return GL_TRUE

- * or GL_FALSE to indicate result.

- */

-static INLINE GLboolean

-eval_condition(const struct gl_program_machine *machine,

-               const struct prog_instruction *inst)

-{

-   const GLuint swizzle = inst->DstReg.CondSwizzle;

-   const GLuint condMask = inst->DstReg.CondMask;

-   if (test_cc(machine->CondCodes[GET_SWZ(swizzle, 0)], condMask) ||

-       test_cc(machine->CondCodes[GET_SWZ(swizzle, 1)], condMask) ||

-       test_cc(machine->CondCodes[GET_SWZ(swizzle, 2)], condMask) ||

-       test_cc(machine->CondCodes[GET_SWZ(swizzle, 3)], condMask)) {

-      return GL_TRUE;

-   }

-   else {

-      return GL_FALSE;

-   }

-}

-

-

-

-/**

- * Store 4 floats into a register.  Observe the instructions saturate and

- * set-condition-code flags.

- */

-static void

-store_vector4(const struct prog_instruction *inst,

-              struct gl_program_machine *machine, const GLfloat value[4])

-{

-   const struct prog_dst_register *dstReg = &(inst->DstReg);

-   const GLboolean clamp = inst->SaturateMode == SATURATE_ZERO_ONE;

-   GLuint writeMask = dstReg->WriteMask;

-   GLfloat clampedValue[4];

-   GLfloat *dst = get_dst_register_pointer(dstReg, machine);

-

-#if 0

-   if (value[0] > 1.0e10 ||

-       IS_INF_OR_NAN(value[0]) ||

-       IS_INF_OR_NAN(value[1]) ||

-       IS_INF_OR_NAN(value[2]) || IS_INF_OR_NAN(value[3]))

-      printf("store %g %g %g %g\n", value[0], value[1], value[2], value[3]);

-#endif

-

-   if (clamp) {

-      clampedValue[0] = CLAMP(value[0], 0.0F, 1.0F);

-      clampedValue[1] = CLAMP(value[1], 0.0F, 1.0F);

-      clampedValue[2] = CLAMP(value[2], 0.0F, 1.0F);

-      clampedValue[3] = CLAMP(value[3], 0.0F, 1.0F);

-      value = clampedValue;

-   }

-

-   if (dstReg->CondMask != COND_TR) {

-      /* condition codes may turn off some writes */

-      if (writeMask & WRITEMASK_X) {

-         if (!test_cc(machine->CondCodes[GET_SWZ(dstReg->CondSwizzle, 0)],

-                      dstReg->CondMask))

-            writeMask &= ~WRITEMASK_X;

-      }

-      if (writeMask & WRITEMASK_Y) {

-         if (!test_cc(machine->CondCodes[GET_SWZ(dstReg->CondSwizzle, 1)],

-                      dstReg->CondMask))

-            writeMask &= ~WRITEMASK_Y;

-      }

-      if (writeMask & WRITEMASK_Z) {

-         if (!test_cc(machine->CondCodes[GET_SWZ(dstReg->CondSwizzle, 2)],

-                      dstReg->CondMask))

-            writeMask &= ~WRITEMASK_Z;

-      }

-      if (writeMask & WRITEMASK_W) {

-         if (!test_cc(machine->CondCodes[GET_SWZ(dstReg->CondSwizzle, 3)],

-                      dstReg->CondMask))

-            writeMask &= ~WRITEMASK_W;

-      }

-   }

-

-#ifdef NAN_CHECK

-   assert(!IS_INF_OR_NAN(value[0]));

-   assert(!IS_INF_OR_NAN(value[0]));

-   assert(!IS_INF_OR_NAN(value[0]));

-   assert(!IS_INF_OR_NAN(value[0]));

-#endif

-

-   if (writeMask & WRITEMASK_X)

-      dst[0] = value[0];

-   if (writeMask & WRITEMASK_Y)

-      dst[1] = value[1];

-   if (writeMask & WRITEMASK_Z)

-      dst[2] = value[2];

-   if (writeMask & WRITEMASK_W)

-      dst[3] = value[3];

-

-   if (inst->CondUpdate) {

-      if (writeMask & WRITEMASK_X)

-         machine->CondCodes[0] = generate_cc(value[0]);

-      if (writeMask & WRITEMASK_Y)

-         machine->CondCodes[1] = generate_cc(value[1]);

-      if (writeMask & WRITEMASK_Z)

-         machine->CondCodes[2] = generate_cc(value[2]);

-      if (writeMask & WRITEMASK_W)

-         machine->CondCodes[3] = generate_cc(value[3]);

-#if DEBUG_PROG

-      printf("CondCodes=(%s,%s,%s,%s) for:\n",

-             _mesa_condcode_string(machine->CondCodes[0]),

-             _mesa_condcode_string(machine->CondCodes[1]),

-             _mesa_condcode_string(machine->CondCodes[2]),

-             _mesa_condcode_string(machine->CondCodes[3]));

-#endif

-   }

-}

-

-

-/**

- * Store 4 uints into a register.  Observe the set-condition-code flags.

- */

-static void

-store_vector4ui(const struct prog_instruction *inst,

-                struct gl_program_machine *machine, const GLuint value[4])

-{

-   const struct prog_dst_register *dstReg = &(inst->DstReg);

-   GLuint writeMask = dstReg->WriteMask;

-   GLuint *dst = (GLuint *) get_dst_register_pointer(dstReg, machine);

-

-   if (dstReg->CondMask != COND_TR) {

-      /* condition codes may turn off some writes */

-      if (writeMask & WRITEMASK_X) {

-         if (!test_cc(machine->CondCodes[GET_SWZ(dstReg->CondSwizzle, 0)],

-                      dstReg->CondMask))

-            writeMask &= ~WRITEMASK_X;

-      }

-      if (writeMask & WRITEMASK_Y) {

-         if (!test_cc(machine->CondCodes[GET_SWZ(dstReg->CondSwizzle, 1)],

-                      dstReg->CondMask))

-            writeMask &= ~WRITEMASK_Y;

-      }

-      if (writeMask & WRITEMASK_Z) {

-         if (!test_cc(machine->CondCodes[GET_SWZ(dstReg->CondSwizzle, 2)],

-                      dstReg->CondMask))

-            writeMask &= ~WRITEMASK_Z;

-      }

-      if (writeMask & WRITEMASK_W) {

-         if (!test_cc(machine->CondCodes[GET_SWZ(dstReg->CondSwizzle, 3)],

-                      dstReg->CondMask))

-            writeMask &= ~WRITEMASK_W;

-      }

-   }

-

-   if (writeMask & WRITEMASK_X)

-      dst[0] = value[0];

-   if (writeMask & WRITEMASK_Y)

-      dst[1] = value[1];

-   if (writeMask & WRITEMASK_Z)

-      dst[2] = value[2];

-   if (writeMask & WRITEMASK_W)

-      dst[3] = value[3];

-

-   if (inst->CondUpdate) {

-      if (writeMask & WRITEMASK_X)

-         machine->CondCodes[0] = generate_cc((float)value[0]);

-      if (writeMask & WRITEMASK_Y)

-         machine->CondCodes[1] = generate_cc((float)value[1]);

-      if (writeMask & WRITEMASK_Z)

-         machine->CondCodes[2] = generate_cc((float)value[2]);

-      if (writeMask & WRITEMASK_W)

-         machine->CondCodes[3] = generate_cc((float)value[3]);

-#if DEBUG_PROG

-      printf("CondCodes=(%s,%s,%s,%s) for:\n",

-             _mesa_condcode_string(machine->CondCodes[0]),

-             _mesa_condcode_string(machine->CondCodes[1]),

-             _mesa_condcode_string(machine->CondCodes[2]),

-             _mesa_condcode_string(machine->CondCodes[3]));

-#endif

-   }

-}

-

-

-

-/**

- * Execute the given vertex/fragment program.

- *

- * \param ctx  rendering context

- * \param program  the program to execute

- * \param machine  machine state (must be initialized)

- * \return GL_TRUE if program completed or GL_FALSE if program executed KIL.

- */

-GLboolean

-_mesa_execute_program(struct gl_context * ctx,

-                      const struct gl_program *program,

-                      struct gl_program_machine *machine)

-{

-   const GLuint numInst = program->NumInstructions;

-   const GLuint maxExec = 10000;

-   GLuint pc, numExec = 0;

-

-   machine->CurProgram = program;

-

-   if (DEBUG_PROG) {

-      printf("execute program %u --------------------\n", program->Id);

-   }

-

-   if (program->Target == GL_VERTEX_PROGRAM_ARB) {

-      machine->EnvParams = ctx->VertexProgram.Parameters;

-   }

-   else {

-      machine->EnvParams = ctx->FragmentProgram.Parameters;

-   }

-

-   for (pc = 0; pc < numInst; pc++) {

-      const struct prog_instruction *inst = program->Instructions + pc;

-

-      if (DEBUG_PROG) {

-         _mesa_print_instruction(inst);

-      }

-

-      switch (inst->Opcode) {

-      case OPCODE_ABS:

-         {

-            GLfloat a[4], result[4];

-            fetch_vector4(&inst->SrcReg[0], machine, a);

-            result[0] = FABSF(a[0]);

-            result[1] = FABSF(a[1]);

-            result[2] = FABSF(a[2]);

-            result[3] = FABSF(a[3]);

-            store_vector4(inst, machine, result);

-         }

-         break;

-      case OPCODE_ADD:

-         {

-            GLfloat a[4], b[4], result[4];

-            fetch_vector4(&inst->SrcReg[0], machine, a);

-            fetch_vector4(&inst->SrcReg[1], machine, b);

-            result[0] = a[0] + b[0];

-            result[1] = a[1] + b[1];

-            result[2] = a[2] + b[2];

-            result[3] = a[3] + b[3];

-            store_vector4(inst, machine, result);

-            if (DEBUG_PROG) {

-               printf("ADD (%g %g %g %g) = (%g %g %g %g) + (%g %g %g %g)\n",

-                      result[0], result[1], result[2], result[3],

-                      a[0], a[1], a[2], a[3], b[0], b[1], b[2], b[3]);

-            }

-         }

-         break;

-      case OPCODE_AND:     /* bitwise AND */

-         {

-            GLuint a[4], b[4], result[4];

-            fetch_vector4ui(&inst->SrcReg[0], machine, a);

-            fetch_vector4ui(&inst->SrcReg[1], machine, b);

-            result[0] = a[0] & b[0];

-            result[1] = a[1] & b[1];

-            result[2] = a[2] & b[2];

-            result[3] = a[3] & b[3];

-            store_vector4ui(inst, machine, result);

-         }

-         break;

-      case OPCODE_ARL:

-         {

-            GLfloat t[4];

-            fetch_vector4(&inst->SrcReg[0], machine, t);

-            machine->AddressReg[0][0] = IFLOOR(t[0]);

-            if (DEBUG_PROG) {

-               printf("ARL %d\n", machine->AddressReg[0][0]);

-            }

-         }

-         break;

-      case OPCODE_BGNLOOP:

-         /* no-op */

-         ASSERT(program->Instructions[inst->BranchTarget].Opcode

-                == OPCODE_ENDLOOP);

-         break;

-      case OPCODE_ENDLOOP:

-         /* subtract 1 here since pc is incremented by for(pc) loop */

-         ASSERT(program->Instructions[inst->BranchTarget].Opcode

-                == OPCODE_BGNLOOP);

-         pc = inst->BranchTarget - 1;   /* go to matching BNGLOOP */

-         break;

-      case OPCODE_BGNSUB:      /* begin subroutine */

-         break;

-      case OPCODE_ENDSUB:      /* end subroutine */

-         break;

-      case OPCODE_BRA:         /* branch (conditional) */

-         if (eval_condition(machine, inst)) {

-            /* take branch */

-            /* Subtract 1 here since we'll do pc++ below */

-            pc = inst->BranchTarget - 1;

-         }

-         break;

-      case OPCODE_BRK:         /* break out of loop (conditional) */

-         ASSERT(program->Instructions[inst->BranchTarget].Opcode

-                == OPCODE_ENDLOOP);

-         if (eval_condition(machine, inst)) {

-            /* break out of loop */

-            /* pc++ at end of for-loop will put us after the ENDLOOP inst */

-            pc = inst->BranchTarget;

-         }

-         break;

-      case OPCODE_CONT:        /* continue loop (conditional) */

-         ASSERT(program->Instructions[inst->BranchTarget].Opcode

-                == OPCODE_ENDLOOP);

-         if (eval_condition(machine, inst)) {

-            /* continue at ENDLOOP */

-            /* Subtract 1 here since we'll do pc++ at end of for-loop */

-            pc = inst->BranchTarget - 1;

-         }

-         break;

-      case OPCODE_CAL:         /* Call subroutine (conditional) */

-         if (eval_condition(machine, inst)) {

-            /* call the subroutine */

-            if (machine->StackDepth >= MAX_PROGRAM_CALL_DEPTH) {

-               return GL_TRUE;  /* Per GL_NV_vertex_program2 spec */

-            }

-            machine->CallStack[machine->StackDepth++] = pc + 1; /* next inst */

-            /* Subtract 1 here since we'll do pc++ at end of for-loop */

-            pc = inst->BranchTarget - 1;

-         }

-         break;

-      case OPCODE_CMP:

-         {

-            GLfloat a[4], b[4], c[4], result[4];

-            fetch_vector4(&inst->SrcReg[0], machine, a);

-            fetch_vector4(&inst->SrcReg[1], machine, b);

-            fetch_vector4(&inst->SrcReg[2], machine, c);

-            result[0] = a[0] < 0.0F ? b[0] : c[0];

-            result[1] = a[1] < 0.0F ? b[1] : c[1];

-            result[2] = a[2] < 0.0F ? b[2] : c[2];

-            result[3] = a[3] < 0.0F ? b[3] : c[3];

-            store_vector4(inst, machine, result);

-            if (DEBUG_PROG) {

-               printf("CMP (%g %g %g %g) = (%g %g %g %g) < 0 ? (%g %g %g %g) : (%g %g %g %g)\n",

-                      result[0], result[1], result[2], result[3],

-                      a[0], a[1], a[2], a[3],

-                      b[0], b[1], b[2], b[3],

-                      c[0], c[1], c[2], c[3]);

-            }

-         }

-         break;

-      case OPCODE_COS:

-         {

-            GLfloat a[4], result[4];

-            fetch_vector1(&inst->SrcReg[0], machine, a);

-            result[0] = result[1] = result[2] = result[3]

-               = (GLfloat) cos(a[0]);

-            store_vector4(inst, machine, result);

-         }

-         break;

-      case OPCODE_DDX:         /* Partial derivative with respect to X */

-         {

-            GLfloat result[4];

-            fetch_vector4_deriv(ctx, &inst->SrcReg[0], machine,

-                                'X', result);

-            store_vector4(inst, machine, result);

-         }

-         break;

-      case OPCODE_DDY:         /* Partial derivative with respect to Y */

-         {

-            GLfloat result[4];

-            fetch_vector4_deriv(ctx, &inst->SrcReg[0], machine,

-                                'Y', result);

-            store_vector4(inst, machine, result);

-         }

-         break;

-      case OPCODE_DP2:

-         {

-            GLfloat a[4], b[4], result[4];

-            fetch_vector4(&inst->SrcReg[0], machine, a);

-            fetch_vector4(&inst->SrcReg[1], machine, b);

-            result[0] = result[1] = result[2] = result[3] = DOT2(a, b);

-            store_vector4(inst, machine, result);

-            if (DEBUG_PROG) {

-               printf("DP2 %g = (%g %g) . (%g %g)\n",

-                      result[0], a[0], a[1], b[0], b[1]);

-            }

-         }

-         break;

-      case OPCODE_DP2A:

-         {

-            GLfloat a[4], b[4], c, result[4];

-            fetch_vector4(&inst->SrcReg[0], machine, a);

-            fetch_vector4(&inst->SrcReg[1], machine, b);

-            fetch_vector1(&inst->SrcReg[1], machine, &c);

-            result[0] = result[1] = result[2] = result[3] = DOT2(a, b) + c;

-            store_vector4(inst, machine, result);

-            if (DEBUG_PROG) {

-               printf("DP2A %g = (%g %g) . (%g %g) + %g\n",

-                      result[0], a[0], a[1], b[0], b[1], c);

-            }

-         }

-         break;

-      case OPCODE_DP3:

-         {

-            GLfloat a[4], b[4], result[4];

-            fetch_vector4(&inst->SrcReg[0], machine, a);

-            fetch_vector4(&inst->SrcReg[1], machine, b);

-            result[0] = result[1] = result[2] = result[3] = DOT3(a, b);

-            store_vector4(inst, machine, result);

-            if (DEBUG_PROG) {

-               printf("DP3 %g = (%g %g %g) . (%g %g %g)\n",

-                      result[0], a[0], a[1], a[2], b[0], b[1], b[2]);

-            }

-         }

-         break;

-      case OPCODE_DP4:

-         {

-            GLfloat a[4], b[4], result[4];

-            fetch_vector4(&inst->SrcReg[0], machine, a);

-            fetch_vector4(&inst->SrcReg[1], machine, b);

-            result[0] = result[1] = result[2] = result[3] = DOT4(a, b);

-            store_vector4(inst, machine, result);

-            if (DEBUG_PROG) {

-               printf("DP4 %g = (%g, %g %g %g) . (%g, %g %g %g)\n",

-                      result[0], a[0], a[1], a[2], a[3],

-                      b[0], b[1], b[2], b[3]);

-            }

-         }

-         break;

-      case OPCODE_DPH:

-         {

-            GLfloat a[4], b[4], result[4];

-            fetch_vector4(&inst->SrcReg[0], machine, a);

-            fetch_vector4(&inst->SrcReg[1], machine, b);

-            result[0] = result[1] = result[2] = result[3] = DOT3(a, b) + b[3];

-            store_vector4(inst, machine, result);

-         }

-         break;

-      case OPCODE_DST:         /* Distance vector */

-         {

-            GLfloat a[4], b[4], result[4];

-            fetch_vector4(&inst->SrcReg[0], machine, a);

-            fetch_vector4(&inst->SrcReg[1], machine, b);

-            result[0] = 1.0F;

-            result[1] = a[1] * b[1];

-            result[2] = a[2];

-            result[3] = b[3];

-            store_vector4(inst, machine, result);

-         }

-         break;

-      case OPCODE_EXP:

-         {

-            GLfloat t[4], q[4], floor_t0;

-            fetch_vector1(&inst->SrcReg[0], machine, t);

-            floor_t0 = FLOORF(t[0]);

-            if (floor_t0 > FLT_MAX_EXP) {

-               SET_POS_INFINITY(q[0]);

-               SET_POS_INFINITY(q[2]);

-            }

-            else if (floor_t0 < FLT_MIN_EXP) {

-               q[0] = 0.0F;

-               q[2] = 0.0F;

-            }

-            else {

-               q[0] = LDEXPF(1.0, (int) floor_t0);

-               /* Note: GL_NV_vertex_program expects 

-                * result.z = result.x * APPX(result.y)

-                * We do what the ARB extension says.

-                */

-               q[2] = (GLfloat) pow(2.0, t[0]);

-            }

-            q[1] = t[0] - floor_t0;

-            q[3] = 1.0F;

-            store_vector4( inst, machine, q );

-         }

-         break;

-      case OPCODE_EX2:         /* Exponential base 2 */

-         {

-            GLfloat a[4], result[4], val;

-            fetch_vector1(&inst->SrcReg[0], machine, a);

-            val = (GLfloat) pow(2.0, a[0]);

-            /*

-            if (IS_INF_OR_NAN(val))

-               val = 1.0e10;

-            */

-            result[0] = result[1] = result[2] = result[3] = val;

-            store_vector4(inst, machine, result);

-         }

-         break;

-      case OPCODE_FLR:

-         {

-            GLfloat a[4], result[4];

-            fetch_vector4(&inst->SrcReg[0], machine, a);

-            result[0] = FLOORF(a[0]);

-            result[1] = FLOORF(a[1]);

-            result[2] = FLOORF(a[2]);

-            result[3] = FLOORF(a[3]);

-            store_vector4(inst, machine, result);

-         }

-         break;

-      case OPCODE_FRC:

-         {

-            GLfloat a[4], result[4];

-            fetch_vector4(&inst->SrcReg[0], machine, a);

-            result[0] = a[0] - FLOORF(a[0]);

-            result[1] = a[1] - FLOORF(a[1]);

-            result[2] = a[2] - FLOORF(a[2]);

-            result[3] = a[3] - FLOORF(a[3]);

-            store_vector4(inst, machine, result);

-         }

-         break;

-      case OPCODE_IF:

-         {

-            GLboolean cond;

-            ASSERT(program->Instructions[inst->BranchTarget].Opcode

-                   == OPCODE_ELSE ||

-                   program->Instructions[inst->BranchTarget].Opcode

-                   == OPCODE_ENDIF);

-            /* eval condition */

-            if (inst->SrcReg[0].File != PROGRAM_UNDEFINED) {

-               GLfloat a[4];

-               fetch_vector1(&inst->SrcReg[0], machine, a);

-               cond = (a[0] != 0.0);

-            }

-            else {

-               cond = eval_condition(machine, inst);

-            }

-            if (DEBUG_PROG) {

-               printf("IF: %d\n", cond);

-            }

-            /* do if/else */

-            if (cond) {

-               /* do if-clause (just continue execution) */

-            }

-            else {

-               /* go to the instruction after ELSE or ENDIF */

-               assert(inst->BranchTarget >= 0);

-               pc = inst->BranchTarget;

-            }

-         }

-         break;

-      case OPCODE_ELSE:

-         /* goto ENDIF */

-         ASSERT(program->Instructions[inst->BranchTarget].Opcode

-                == OPCODE_ENDIF);

-         assert(inst->BranchTarget >= 0);

-         pc = inst->BranchTarget;

-         break;

-      case OPCODE_ENDIF:

-         /* nothing */

-         break;

-      case OPCODE_KIL_NV:      /* NV_f_p only (conditional) */

-         if (eval_condition(machine, inst)) {

-            return GL_FALSE;

-         }

-         break;

-      case OPCODE_KIL:         /* ARB_f_p only */

-         {

-            GLfloat a[4];

-            fetch_vector4(&inst->SrcReg[0], machine, a);

-            if (DEBUG_PROG) {

-               printf("KIL if (%g %g %g %g) <= 0.0\n",

-                      a[0], a[1], a[2], a[3]);

-            }

-

-            if (a[0] < 0.0F || a[1] < 0.0F || a[2] < 0.0F || a[3] < 0.0F) {

-               return GL_FALSE;

-            }

-         }

-         break;

-      case OPCODE_LG2:         /* log base 2 */

-         {

-            GLfloat a[4], result[4], val;

-            fetch_vector1(&inst->SrcReg[0], machine, a);

-	    /* The fast LOG2 macro doesn't meet the precision requirements.

-	     */

-            if (a[0] == 0.0F) {

-               val = -FLT_MAX;

-            }

-            else {

-               val = (float)(log(a[0]) * 1.442695F);

-            }

-            result[0] = result[1] = result[2] = result[3] = val;

-            store_vector4(inst, machine, result);

-         }

-         break;

-      case OPCODE_LIT:

-         {

-            const GLfloat epsilon = 1.0F / 256.0F;      /* from NV VP spec */

-            GLfloat a[4], result[4];

-            fetch_vector4(&inst->SrcReg[0], machine, a);

-            a[0] = MAX2(a[0], 0.0F);

-            a[1] = MAX2(a[1], 0.0F);

-            /* XXX ARB version clamps a[3], NV version doesn't */

-            a[3] = CLAMP(a[3], -(128.0F - epsilon), (128.0F - epsilon));

-            result[0] = 1.0F;

-            result[1] = a[0];

-            /* XXX we could probably just use pow() here */

-            if (a[0] > 0.0F) {

-               if (a[1] == 0.0 && a[3] == 0.0)

-                  result[2] = 1.0F;

-               else

-                  result[2] = (GLfloat) pow(a[1], a[3]);

-            }

-            else {

-               result[2] = 0.0F;

-            }

-            result[3] = 1.0F;

-            store_vector4(inst, machine, result);

-            if (DEBUG_PROG) {

-               printf("LIT (%g %g %g %g) : (%g %g %g %g)\n",

-                      result[0], result[1], result[2], result[3],

-                      a[0], a[1], a[2], a[3]);

-            }

-         }

-         break;

-      case OPCODE_LOG:

-         {

-            GLfloat t[4], q[4], abs_t0;

-            fetch_vector1(&inst->SrcReg[0], machine, t);

-            abs_t0 = FABSF(t[0]);

-            if (abs_t0 != 0.0F) {

-               /* Since we really can't handle infinite values on VMS

-                * like other OSes we'll use __MAXFLOAT to represent

-                * infinity.  This may need some tweaking.

-                */

-#ifdef VMS

-               if (abs_t0 == __MAXFLOAT)

-#else

-               if (IS_INF_OR_NAN(abs_t0))

-#endif

-               {

-                  SET_POS_INFINITY(q[0]);

-                  q[1] = 1.0F;

-                  SET_POS_INFINITY(q[2]);

-               }

-               else {

-                  int exponent;

-                  GLfloat mantissa = FREXPF(t[0], &exponent);

-                  q[0] = (GLfloat) (exponent - 1);

-                  q[1] = (GLfloat) (2.0 * mantissa); /* map [.5, 1) -> [1, 2) */

-

-		  /* The fast LOG2 macro doesn't meet the precision

-		   * requirements.

-		   */

-                  q[2] = (float)(log(t[0]) * 1.442695F);

-               }

-            }

-            else {

-               SET_NEG_INFINITY(q[0]);

-               q[1] = 1.0F;

-               SET_NEG_INFINITY(q[2]);

-            }

-            q[3] = 1.0;

-            store_vector4(inst, machine, q);

-         }

-         break;

-      case OPCODE_LRP:

-         {

-            GLfloat a[4], b[4], c[4], result[4];

-            fetch_vector4(&inst->SrcReg[0], machine, a);

-            fetch_vector4(&inst->SrcReg[1], machine, b);

-            fetch_vector4(&inst->SrcReg[2], machine, c);

-            result[0] = a[0] * b[0] + (1.0F - a[0]) * c[0];

-            result[1] = a[1] * b[1] + (1.0F - a[1]) * c[1];

-            result[2] = a[2] * b[2] + (1.0F - a[2]) * c[2];

-            result[3] = a[3] * b[3] + (1.0F - a[3]) * c[3];

-            store_vector4(inst, machine, result);

-            if (DEBUG_PROG) {

-               printf("LRP (%g %g %g %g) = (%g %g %g %g), "

-                      "(%g %g %g %g), (%g %g %g %g)\n",

-                      result[0], result[1], result[2], result[3],

-                      a[0], a[1], a[2], a[3],

-                      b[0], b[1], b[2], b[3], c[0], c[1], c[2], c[3]);

-            }

-         }

-         break;

-      case OPCODE_MAD:

-         {

-            GLfloat a[4], b[4], c[4], result[4];

-            fetch_vector4(&inst->SrcReg[0], machine, a);

-            fetch_vector4(&inst->SrcReg[1], machine, b);

-            fetch_vector4(&inst->SrcReg[2], machine, c);

-            result[0] = a[0] * b[0] + c[0];

-            result[1] = a[1] * b[1] + c[1];

-            result[2] = a[2] * b[2] + c[2];

-            result[3] = a[3] * b[3] + c[3];

-            store_vector4(inst, machine, result);

-            if (DEBUG_PROG) {

-               printf("MAD (%g %g %g %g) = (%g %g %g %g) * "

-                      "(%g %g %g %g) + (%g %g %g %g)\n",

-                      result[0], result[1], result[2], result[3],

-                      a[0], a[1], a[2], a[3],

-                      b[0], b[1], b[2], b[3], c[0], c[1], c[2], c[3]);

-            }

-         }

-         break;

-      case OPCODE_MAX:

-         {

-            GLfloat a[4], b[4], result[4];

-            fetch_vector4(&inst->SrcReg[0], machine, a);

-            fetch_vector4(&inst->SrcReg[1], machine, b);

-            result[0] = MAX2(a[0], b[0]);

-            result[1] = MAX2(a[1], b[1]);

-            result[2] = MAX2(a[2], b[2]);

-            result[3] = MAX2(a[3], b[3]);

-            store_vector4(inst, machine, result);

-            if (DEBUG_PROG) {

-               printf("MAX (%g %g %g %g) = (%g %g %g %g), (%g %g %g %g)\n",

-                      result[0], result[1], result[2], result[3],

-                      a[0], a[1], a[2], a[3], b[0], b[1], b[2], b[3]);

-            }

-         }

-         break;

-      case OPCODE_MIN:

-         {

-            GLfloat a[4], b[4], result[4];

-            fetch_vector4(&inst->SrcReg[0], machine, a);

-            fetch_vector4(&inst->SrcReg[1], machine, b);

-            result[0] = MIN2(a[0], b[0]);

-            result[1] = MIN2(a[1], b[1]);

-            result[2] = MIN2(a[2], b[2]);

-            result[3] = MIN2(a[3], b[3]);

-            store_vector4(inst, machine, result);

-         }

-         break;

-      case OPCODE_MOV:

-         {

-            GLfloat result[4];

-            fetch_vector4(&inst->SrcReg[0], machine, result);

-            store_vector4(inst, machine, result);

-            if (DEBUG_PROG) {

-               printf("MOV (%g %g %g %g)\n",

-                      result[0], result[1], result[2], result[3]);

-            }

-         }

-         break;

-      case OPCODE_MUL:

-         {

-            GLfloat a[4], b[4], result[4];

-            fetch_vector4(&inst->SrcReg[0], machine, a);

-            fetch_vector4(&inst->SrcReg[1], machine, b);

-            result[0] = a[0] * b[0];

-            result[1] = a[1] * b[1];

-            result[2] = a[2] * b[2];

-            result[3] = a[3] * b[3];

-            store_vector4(inst, machine, result);

-            if (DEBUG_PROG) {

-               printf("MUL (%g %g %g %g) = (%g %g %g %g) * (%g %g %g %g)\n",

-                      result[0], result[1], result[2], result[3],

-                      a[0], a[1], a[2], a[3], b[0], b[1], b[2], b[3]);

-            }

-         }

-         break;

-      case OPCODE_NOISE1:

-         {

-            GLfloat a[4], result[4];

-            fetch_vector1(&inst->SrcReg[0], machine, a);

-            result[0] =

-               result[1] =

-               result[2] =

-               result[3] = _mesa_noise1(a[0]);

-            store_vector4(inst, machine, result);

-         }

-         break;

-      case OPCODE_NOISE2:

-         {

-            GLfloat a[4], result[4];

-            fetch_vector4(&inst->SrcReg[0], machine, a);

-            result[0] =

-               result[1] =

-               result[2] = result[3] = _mesa_noise2(a[0], a[1]);

-            store_vector4(inst, machine, result);

-         }

-         break;

-      case OPCODE_NOISE3:

-         {

-            GLfloat a[4], result[4];

-            fetch_vector4(&inst->SrcReg[0], machine, a);

-            result[0] =

-               result[1] =

-               result[2] =

-               result[3] = _mesa_noise3(a[0], a[1], a[2]);

-            store_vector4(inst, machine, result);

-         }

-         break;

-      case OPCODE_NOISE4:

-         {

-            GLfloat a[4], result[4];

-            fetch_vector4(&inst->SrcReg[0], machine, a);

-            result[0] =

-               result[1] =

-               result[2] =

-               result[3] = _mesa_noise4(a[0], a[1], a[2], a[3]);

-            store_vector4(inst, machine, result);

-         }

-         break;

-      case OPCODE_NOP:

-         break;

-      case OPCODE_NOT:         /* bitwise NOT */

-         {

-            GLuint a[4], result[4];

-            fetch_vector4ui(&inst->SrcReg[0], machine, a);

-            result[0] = ~a[0];

-            result[1] = ~a[1];

-            result[2] = ~a[2];

-            result[3] = ~a[3];

-            store_vector4ui(inst, machine, result);

-         }

-         break;

-      case OPCODE_NRM3:        /* 3-component normalization */

-         {

-            GLfloat a[4], result[4];

-            GLfloat tmp;

-            fetch_vector4(&inst->SrcReg[0], machine, a);

-            tmp = a[0] * a[0] + a[1] * a[1] + a[2] * a[2];

-            if (tmp != 0.0F)

-               tmp = INV_SQRTF(tmp);

-            result[0] = tmp * a[0];

-            result[1] = tmp * a[1];

-            result[2] = tmp * a[2];

-            result[3] = 0.0;  /* undefined, but prevent valgrind warnings */

-            store_vector4(inst, machine, result);

-         }

-         break;

-      case OPCODE_NRM4:        /* 4-component normalization */

-         {

-            GLfloat a[4], result[4];

-            GLfloat tmp;

-            fetch_vector4(&inst->SrcReg[0], machine, a);

-            tmp = a[0] * a[0] + a[1] * a[1] + a[2] * a[2] + a[3] * a[3];

-            if (tmp != 0.0F)

-               tmp = INV_SQRTF(tmp);

-            result[0] = tmp * a[0];

-            result[1] = tmp * a[1];

-            result[2] = tmp * a[2];

-            result[3] = tmp * a[3];

-            store_vector4(inst, machine, result);

-         }

-         break;

-      case OPCODE_OR:          /* bitwise OR */

-         {

-            GLuint a[4], b[4], result[4];

-            fetch_vector4ui(&inst->SrcReg[0], machine, a);

-            fetch_vector4ui(&inst->SrcReg[1], machine, b);

-            result[0] = a[0] | b[0];

-            result[1] = a[1] | b[1];

-            result[2] = a[2] | b[2];

-            result[3] = a[3] | b[3];

-            store_vector4ui(inst, machine, result);

-         }

-         break;

-      case OPCODE_PK2H:        /* pack two 16-bit floats in one 32-bit float */

-         {

-            GLfloat a[4];

-            GLuint result[4];

-            GLhalfNV hx, hy;

-            fetch_vector4(&inst->SrcReg[0], machine, a);

-            hx = _mesa_float_to_half(a[0]);

-            hy = _mesa_float_to_half(a[1]);

-            result[0] =

-            result[1] =

-            result[2] =

-            result[3] = hx | (hy << 16);

-            store_vector4ui(inst, machine, result);

-         }

-         break;

-      case OPCODE_PK2US:       /* pack two GLushorts into one 32-bit float */

-         {

-            GLfloat a[4];

-            GLuint result[4], usx, usy;

-            fetch_vector4(&inst->SrcReg[0], machine, a);

-            a[0] = CLAMP(a[0], 0.0F, 1.0F);

-            a[1] = CLAMP(a[1], 0.0F, 1.0F);

-            usx = IROUND(a[0] * 65535.0F);

-            usy = IROUND(a[1] * 65535.0F);

-            result[0] =

-            result[1] =

-            result[2] =

-            result[3] = usx | (usy << 16);

-            store_vector4ui(inst, machine, result);

-         }

-         break;

-      case OPCODE_PK4B:        /* pack four GLbytes into one 32-bit float */

-         {

-            GLfloat a[4];

-            GLuint result[4], ubx, uby, ubz, ubw;

-            fetch_vector4(&inst->SrcReg[0], machine, a);

-            a[0] = CLAMP(a[0], -128.0F / 127.0F, 1.0F);

-            a[1] = CLAMP(a[1], -128.0F / 127.0F, 1.0F);

-            a[2] = CLAMP(a[2], -128.0F / 127.0F, 1.0F);

-            a[3] = CLAMP(a[3], -128.0F / 127.0F, 1.0F);

-            ubx = IROUND(127.0F * a[0] + 128.0F);

-            uby = IROUND(127.0F * a[1] + 128.0F);

-            ubz = IROUND(127.0F * a[2] + 128.0F);

-            ubw = IROUND(127.0F * a[3] + 128.0F);

-            result[0] =

-            result[1] =

-            result[2] =

-            result[3] = ubx | (uby << 8) | (ubz << 16) | (ubw << 24);

-            store_vector4ui(inst, machine, result);

-         }

-         break;

-      case OPCODE_PK4UB:       /* pack four GLubytes into one 32-bit float */

-         {

-            GLfloat a[4];

-            GLuint result[4], ubx, uby, ubz, ubw;

-            fetch_vector4(&inst->SrcReg[0], machine, a);

-            a[0] = CLAMP(a[0], 0.0F, 1.0F);

-            a[1] = CLAMP(a[1], 0.0F, 1.0F);

-            a[2] = CLAMP(a[2], 0.0F, 1.0F);

-            a[3] = CLAMP(a[3], 0.0F, 1.0F);

-            ubx = IROUND(255.0F * a[0]);

-            uby = IROUND(255.0F * a[1]);

-            ubz = IROUND(255.0F * a[2]);

-            ubw = IROUND(255.0F * a[3]);

-            result[0] =

-            result[1] =

-            result[2] =

-            result[3] = ubx | (uby << 8) | (ubz << 16) | (ubw << 24);

-            store_vector4ui(inst, machine, result);

-         }

-         break;

-      case OPCODE_POW:

-         {

-            GLfloat a[4], b[4], result[4];

-            fetch_vector1(&inst->SrcReg[0], machine, a);

-            fetch_vector1(&inst->SrcReg[1], machine, b);

-            result[0] = result[1] = result[2] = result[3]

-               = (GLfloat) pow(a[0], b[0]);

-            store_vector4(inst, machine, result);

-         }

-         break;

-      case OPCODE_RCC:  /* clamped riciprocal */

-         {

-            const float largest = 1.884467e+19, smallest = 5.42101e-20;

-            GLfloat a[4], r, result[4];

-            fetch_vector1(&inst->SrcReg[0], machine, a);

-            if (DEBUG_PROG) {

-               if (a[0] == 0)

-                  printf("RCC(0)\n");

-               else if (IS_INF_OR_NAN(a[0]))

-                  printf("RCC(inf)\n");

-            }

-            if (a[0] == 1.0F) {

-               r = 1.0F;

-            }

-            else {

-               r = 1.0F / a[0];

-            }

-            if (positive(r)) {

-               if (r > largest) {

-                  r = largest;

-               }

-               else if (r < smallest) {

-                  r = smallest;

-               }

-            }

-            else {

-               if (r < -largest) {

-                  r = -largest;

-               }

-               else if (r > -smallest) {

-                  r = -smallest;

-               }

-            }

-            result[0] = result[1] = result[2] = result[3] = r;

-            store_vector4(inst, machine, result);

-         }

-         break;

-

-      case OPCODE_RCP:

-         {

-            GLfloat a[4], result[4];

-            fetch_vector1(&inst->SrcReg[0], machine, a);

-            if (DEBUG_PROG) {

-               if (a[0] == 0)

-                  printf("RCP(0)\n");

-               else if (IS_INF_OR_NAN(a[0]))

-                  printf("RCP(inf)\n");

-            }

-            result[0] = result[1] = result[2] = result[3] = 1.0F / a[0];

-            store_vector4(inst, machine, result);

-         }

-         break;

-      case OPCODE_RET:         /* return from subroutine (conditional) */

-         if (eval_condition(machine, inst)) {

-            if (machine->StackDepth == 0) {

-               return GL_TRUE;  /* Per GL_NV_vertex_program2 spec */

-            }

-            /* subtract one because of pc++ in the for loop */

-            pc = machine->CallStack[--machine->StackDepth] - 1;

-         }

-         break;

-      case OPCODE_RFL:         /* reflection vector */

-         {

-            GLfloat axis[4], dir[4], result[4], tmpX, tmpW;

-            fetch_vector4(&inst->SrcReg[0], machine, axis);

-            fetch_vector4(&inst->SrcReg[1], machine, dir);

-            tmpW = DOT3(axis, axis);

-            tmpX = (2.0F * DOT3(axis, dir)) / tmpW;

-            result[0] = tmpX * axis[0] - dir[0];

-            result[1] = tmpX * axis[1] - dir[1];

-            result[2] = tmpX * axis[2] - dir[2];

-            /* result[3] is never written! XXX enforce in parser! */

-            store_vector4(inst, machine, result);

-         }

-         break;

-      case OPCODE_RSQ:         /* 1 / sqrt() */

-         {

-            GLfloat a[4], result[4];

-            fetch_vector1(&inst->SrcReg[0], machine, a);

-            a[0] = FABSF(a[0]);

-            result[0] = result[1] = result[2] = result[3] = INV_SQRTF(a[0]);

-            store_vector4(inst, machine, result);

-            if (DEBUG_PROG) {

-               printf("RSQ %g = 1/sqrt(|%g|)\n", result[0], a[0]);

-            }

-         }

-         break;

-      case OPCODE_SCS:         /* sine and cos */

-         {

-            GLfloat a[4], result[4];

-            fetch_vector1(&inst->SrcReg[0], machine, a);

-            result[0] = (GLfloat) cos(a[0]);

-            result[1] = (GLfloat) sin(a[0]);

-            result[2] = 0.0;    /* undefined! */

-            result[3] = 0.0;    /* undefined! */

-            store_vector4(inst, machine, result);

-         }

-         break;

-      case OPCODE_SEQ:         /* set on equal */

-         {

-            GLfloat a[4], b[4], result[4];

-            fetch_vector4(&inst->SrcReg[0], machine, a);

-            fetch_vector4(&inst->SrcReg[1], machine, b);

-            result[0] = (a[0] == b[0]) ? 1.0F : 0.0F;

-            result[1] = (a[1] == b[1]) ? 1.0F : 0.0F;

-            result[2] = (a[2] == b[2]) ? 1.0F : 0.0F;

-            result[3] = (a[3] == b[3]) ? 1.0F : 0.0F;

-            store_vector4(inst, machine, result);

-            if (DEBUG_PROG) {

-               printf("SEQ (%g %g %g %g) = (%g %g %g %g) == (%g %g %g %g)\n",

-                      result[0], result[1], result[2], result[3],

-                      a[0], a[1], a[2], a[3],

-                      b[0], b[1], b[2], b[3]);

-            }

-         }

-         break;

-      case OPCODE_SFL:         /* set false, operands ignored */

-         {

-            static const GLfloat result[4] = { 0.0F, 0.0F, 0.0F, 0.0F };

-            store_vector4(inst, machine, result);

-         }

-         break;

-      case OPCODE_SGE:         /* set on greater or equal */

-         {

-            GLfloat a[4], b[4], result[4];

-            fetch_vector4(&inst->SrcReg[0], machine, a);

-            fetch_vector4(&inst->SrcReg[1], machine, b);

-            result[0] = (a[0] >= b[0]) ? 1.0F : 0.0F;

-            result[1] = (a[1] >= b[1]) ? 1.0F : 0.0F;

-            result[2] = (a[2] >= b[2]) ? 1.0F : 0.0F;

-            result[3] = (a[3] >= b[3]) ? 1.0F : 0.0F;

-            store_vector4(inst, machine, result);

-            if (DEBUG_PROG) {

-               printf("SGE (%g %g %g %g) = (%g %g %g %g) >= (%g %g %g %g)\n",

-                      result[0], result[1], result[2], result[3],

-                      a[0], a[1], a[2], a[3],

-                      b[0], b[1], b[2], b[3]);

-            }

-         }

-         break;

-      case OPCODE_SGT:         /* set on greater */

-         {

-            GLfloat a[4], b[4], result[4];

-            fetch_vector4(&inst->SrcReg[0], machine, a);

-            fetch_vector4(&inst->SrcReg[1], machine, b);

-            result[0] = (a[0] > b[0]) ? 1.0F : 0.0F;

-            result[1] = (a[1] > b[1]) ? 1.0F : 0.0F;

-            result[2] = (a[2] > b[2]) ? 1.0F : 0.0F;

-            result[3] = (a[3] > b[3]) ? 1.0F : 0.0F;

-            store_vector4(inst, machine, result);

-            if (DEBUG_PROG) {

-               printf("SGT (%g %g %g %g) = (%g %g %g %g) > (%g %g %g %g)\n",

-                      result[0], result[1], result[2], result[3],

-                      a[0], a[1], a[2], a[3],

-                      b[0], b[1], b[2], b[3]);

-            }

-         }

-         break;

-      case OPCODE_SIN:

-         {

-            GLfloat a[4], result[4];

-            fetch_vector1(&inst->SrcReg[0], machine, a);

-            result[0] = result[1] = result[2] = result[3]

-               = (GLfloat) sin(a[0]);

-            store_vector4(inst, machine, result);

-         }

-         break;

-      case OPCODE_SLE:         /* set on less or equal */

-         {

-            GLfloat a[4], b[4], result[4];

-            fetch_vector4(&inst->SrcReg[0], machine, a);

-            fetch_vector4(&inst->SrcReg[1], machine, b);

-            result[0] = (a[0] <= b[0]) ? 1.0F : 0.0F;

-            result[1] = (a[1] <= b[1]) ? 1.0F : 0.0F;

-            result[2] = (a[2] <= b[2]) ? 1.0F : 0.0F;

-            result[3] = (a[3] <= b[3]) ? 1.0F : 0.0F;

-            store_vector4(inst, machine, result);

-            if (DEBUG_PROG) {

-               printf("SLE (%g %g %g %g) = (%g %g %g %g) <= (%g %g %g %g)\n",

-                      result[0], result[1], result[2], result[3],

-                      a[0], a[1], a[2], a[3],

-                      b[0], b[1], b[2], b[3]);

-            }

-         }

-         break;

-      case OPCODE_SLT:         /* set on less */

-         {

-            GLfloat a[4], b[4], result[4];

-            fetch_vector4(&inst->SrcReg[0], machine, a);

-            fetch_vector4(&inst->SrcReg[1], machine, b);

-            result[0] = (a[0] < b[0]) ? 1.0F : 0.0F;

-            result[1] = (a[1] < b[1]) ? 1.0F : 0.0F;

-            result[2] = (a[2] < b[2]) ? 1.0F : 0.0F;

-            result[3] = (a[3] < b[3]) ? 1.0F : 0.0F;

-            store_vector4(inst, machine, result);

-            if (DEBUG_PROG) {

-               printf("SLT (%g %g %g %g) = (%g %g %g %g) < (%g %g %g %g)\n",

-                      result[0], result[1], result[2], result[3],

-                      a[0], a[1], a[2], a[3],

-                      b[0], b[1], b[2], b[3]);

-            }

-         }

-         break;

-      case OPCODE_SNE:         /* set on not equal */

-         {

-            GLfloat a[4], b[4], result[4];

-            fetch_vector4(&inst->SrcReg[0], machine, a);

-            fetch_vector4(&inst->SrcReg[1], machine, b);

-            result[0] = (a[0] != b[0]) ? 1.0F : 0.0F;

-            result[1] = (a[1] != b[1]) ? 1.0F : 0.0F;

-            result[2] = (a[2] != b[2]) ? 1.0F : 0.0F;

-            result[3] = (a[3] != b[3]) ? 1.0F : 0.0F;

-            store_vector4(inst, machine, result);

-            if (DEBUG_PROG) {

-               printf("SNE (%g %g %g %g) = (%g %g %g %g) != (%g %g %g %g)\n",

-                      result[0], result[1], result[2], result[3],

-                      a[0], a[1], a[2], a[3],

-                      b[0], b[1], b[2], b[3]);

-            }

-         }

-         break;

-      case OPCODE_SSG:         /* set sign (-1, 0 or +1) */

-         {

-            GLfloat a[4], result[4];

-            fetch_vector4(&inst->SrcReg[0], machine, a);

-            result[0] = (GLfloat) ((a[0] > 0.0F) - (a[0] < 0.0F));

-            result[1] = (GLfloat) ((a[1] > 0.0F) - (a[1] < 0.0F));

-            result[2] = (GLfloat) ((a[2] > 0.0F) - (a[2] < 0.0F));

-            result[3] = (GLfloat) ((a[3] > 0.0F) - (a[3] < 0.0F));

-            store_vector4(inst, machine, result);

-         }

-         break;

-      case OPCODE_STR:         /* set true, operands ignored */

-         {

-            static const GLfloat result[4] = { 1.0F, 1.0F, 1.0F, 1.0F };

-            store_vector4(inst, machine, result);

-         }

-         break;

-      case OPCODE_SUB:

-         {

-            GLfloat a[4], b[4], result[4];

-            fetch_vector4(&inst->SrcReg[0], machine, a);

-            fetch_vector4(&inst->SrcReg[1], machine, b);

-            result[0] = a[0] - b[0];

-            result[1] = a[1] - b[1];

-            result[2] = a[2] - b[2];

-            result[3] = a[3] - b[3];

-            store_vector4(inst, machine, result);

-            if (DEBUG_PROG) {

-               printf("SUB (%g %g %g %g) = (%g %g %g %g) - (%g %g %g %g)\n",

-                      result[0], result[1], result[2], result[3],

-                      a[0], a[1], a[2], a[3], b[0], b[1], b[2], b[3]);

-            }

-         }

-         break;

-      case OPCODE_SWZ:         /* extended swizzle */

-         {

-            const struct prog_src_register *source = &inst->SrcReg[0];

-            const GLfloat *src = get_src_register_pointer(source, machine);

-            GLfloat result[4];

-            GLuint i;

-            for (i = 0; i < 4; i++) {

-               const GLuint swz = GET_SWZ(source->Swizzle, i);

-               if (swz == SWIZZLE_ZERO)

-                  result[i] = 0.0;

-               else if (swz == SWIZZLE_ONE)

-                  result[i] = 1.0;

-               else {

-                  ASSERT(swz >= 0);

-                  ASSERT(swz <= 3);

-                  result[i] = src[swz];

-               }

-               if (source->Negate & (1 << i))

-                  result[i] = -result[i];

-            }

-            store_vector4(inst, machine, result);

-         }

-         break;

-      case OPCODE_TEX:         /* Both ARB and NV frag prog */

-         /* Simple texel lookup */

-         {

-            GLfloat texcoord[4], color[4];

-            fetch_vector4(&inst->SrcReg[0], machine, texcoord);

-

-            fetch_texel(ctx, machine, inst, texcoord, 0.0, color);

-

-            if (DEBUG_PROG) {

-               printf("TEX (%g, %g, %g, %g) = texture[%d][%g, %g, %g, %g]\n",

-                      color[0], color[1], color[2], color[3],

-                      inst->TexSrcUnit,

-                      texcoord[0], texcoord[1], texcoord[2], texcoord[3]);

-            }

-            store_vector4(inst, machine, color);

-         }

-         break;

-      case OPCODE_TXB:         /* GL_ARB_fragment_program only */

-         /* Texel lookup with LOD bias */

-         {

-            GLfloat texcoord[4], color[4], lodBias;

-

-            fetch_vector4(&inst->SrcReg[0], machine, texcoord);

-

-            /* texcoord[3] is the bias to add to lambda */

-            lodBias = texcoord[3];

-

-            fetch_texel(ctx, machine, inst, texcoord, lodBias, color);

-

-            if (DEBUG_PROG) {

-               printf("TXB (%g, %g, %g, %g) = texture[%d][%g %g %g %g]"

-                      "  bias %g\n",

-                      color[0], color[1], color[2], color[3],

-                      inst->TexSrcUnit,

-                      texcoord[0],

-                      texcoord[1],

-                      texcoord[2],

-                      texcoord[3],

-                      lodBias);

-            }

-

-            store_vector4(inst, machine, color);

-         }

-         break;

-      case OPCODE_TXD:         /* GL_NV_fragment_program only */

-         /* Texture lookup w/ partial derivatives for LOD */

-         {

-            GLfloat texcoord[4], dtdx[4], dtdy[4], color[4];

-            fetch_vector4(&inst->SrcReg[0], machine, texcoord);

-            fetch_vector4(&inst->SrcReg[1], machine, dtdx);

-            fetch_vector4(&inst->SrcReg[2], machine, dtdy);

-            machine->FetchTexelDeriv(ctx, texcoord, dtdx, dtdy,

-                                     0.0, /* lodBias */

-                                     inst->TexSrcUnit, color);

-            store_vector4(inst, machine, color);

-         }

-         break;

-      case OPCODE_TXL:

-         /* Texel lookup with explicit LOD */

-         {

-            GLfloat texcoord[4], color[4], lod;

-

-            fetch_vector4(&inst->SrcReg[0], machine, texcoord);

-

-            /* texcoord[3] is the LOD */

-            lod = texcoord[3];

-

-	    machine->FetchTexelLod(ctx, texcoord, lod,

-				   machine->Samplers[inst->TexSrcUnit], color);

-

-            store_vector4(inst, machine, color);

-         }

-         break;

-      case OPCODE_TXP:         /* GL_ARB_fragment_program only */

-         /* Texture lookup w/ projective divide */

-         {

-            GLfloat texcoord[4], color[4];

-

-            fetch_vector4(&inst->SrcReg[0], machine, texcoord);

-            /* Not so sure about this test - if texcoord[3] is

-             * zero, we'd probably be fine except for an ASSERT in

-             * IROUND_POS() which gets triggered by the inf values created.

-             */

-            if (texcoord[3] != 0.0) {

-               texcoord[0] /= texcoord[3];

-               texcoord[1] /= texcoord[3];

-               texcoord[2] /= texcoord[3];

-            }

-

-            fetch_texel(ctx, machine, inst, texcoord, 0.0, color);

-

-            store_vector4(inst, machine, color);

-         }

-         break;

-      case OPCODE_TXP_NV:      /* GL_NV_fragment_program only */

-         /* Texture lookup w/ projective divide, as above, but do not

-          * do the divide by w if sampling from a cube map.

-          */

-         {

-            GLfloat texcoord[4], color[4];

-

-            fetch_vector4(&inst->SrcReg[0], machine, texcoord);

-            if (inst->TexSrcTarget != TEXTURE_CUBE_INDEX &&

-                texcoord[3] != 0.0) {

-               texcoord[0] /= texcoord[3];

-               texcoord[1] /= texcoord[3];

-               texcoord[2] /= texcoord[3];

-            }

-

-            fetch_texel(ctx, machine, inst, texcoord, 0.0, color);

-

-            store_vector4(inst, machine, color);

-         }

-         break;

-      case OPCODE_TRUNC:       /* truncate toward zero */

-         {

-            GLfloat a[4], result[4];

-            fetch_vector4(&inst->SrcReg[0], machine, a);

-            result[0] = (GLfloat) (GLint) a[0];

-            result[1] = (GLfloat) (GLint) a[1];

-            result[2] = (GLfloat) (GLint) a[2];

-            result[3] = (GLfloat) (GLint) a[3];

-            store_vector4(inst, machine, result);

-         }

-         break;

-      case OPCODE_UP2H:        /* unpack two 16-bit floats */

-         {

-            const GLuint raw = fetch_vector1ui(&inst->SrcReg[0], machine);

-            GLfloat result[4];

-            GLushort hx, hy;

-            hx = raw & 0xffff;

-            hy = raw >> 16;

-            result[0] = result[2] = _mesa_half_to_float(hx);

-            result[1] = result[3] = _mesa_half_to_float(hy);

-            store_vector4(inst, machine, result);

-         }

-         break;

-      case OPCODE_UP2US:       /* unpack two GLushorts */

-         {

-            const GLuint raw = fetch_vector1ui(&inst->SrcReg[0], machine);

-            GLfloat result[4];

-            GLushort usx, usy;

-            usx = raw & 0xffff;

-            usy = raw >> 16;

-            result[0] = result[2] = usx * (1.0f / 65535.0f);

-            result[1] = result[3] = usy * (1.0f / 65535.0f);

-            store_vector4(inst, machine, result);

-         }

-         break;

-      case OPCODE_UP4B:        /* unpack four GLbytes */

-         {

-            const GLuint raw = fetch_vector1ui(&inst->SrcReg[0], machine);

-            GLfloat result[4];

-            result[0] = (((raw >> 0) & 0xff) - 128) / 127.0F;

-            result[1] = (((raw >> 8) & 0xff) - 128) / 127.0F;

-            result[2] = (((raw >> 16) & 0xff) - 128) / 127.0F;

-            result[3] = (((raw >> 24) & 0xff) - 128) / 127.0F;

-            store_vector4(inst, machine, result);

-         }

-         break;

-      case OPCODE_UP4UB:       /* unpack four GLubytes */

-         {

-            const GLuint raw = fetch_vector1ui(&inst->SrcReg[0], machine);

-            GLfloat result[4];

-            result[0] = ((raw >> 0) & 0xff) / 255.0F;

-            result[1] = ((raw >> 8) & 0xff) / 255.0F;

-            result[2] = ((raw >> 16) & 0xff) / 255.0F;

-            result[3] = ((raw >> 24) & 0xff) / 255.0F;

-            store_vector4(inst, machine, result);

-         }

-         break;

-      case OPCODE_XOR:         /* bitwise XOR */

-         {

-            GLuint a[4], b[4], result[4];

-            fetch_vector4ui(&inst->SrcReg[0], machine, a);

-            fetch_vector4ui(&inst->SrcReg[1], machine, b);

-            result[0] = a[0] ^ b[0];

-            result[1] = a[1] ^ b[1];

-            result[2] = a[2] ^ b[2];

-            result[3] = a[3] ^ b[3];

-            store_vector4ui(inst, machine, result);

-         }

-         break;

-      case OPCODE_XPD:         /* cross product */

-         {

-            GLfloat a[4], b[4], result[4];

-            fetch_vector4(&inst->SrcReg[0], machine, a);

-            fetch_vector4(&inst->SrcReg[1], machine, b);

-            result[0] = a[1] * b[2] - a[2] * b[1];

-            result[1] = a[2] * b[0] - a[0] * b[2];

-            result[2] = a[0] * b[1] - a[1] * b[0];

-            result[3] = 1.0;

-            store_vector4(inst, machine, result);

-            if (DEBUG_PROG) {

-               printf("XPD (%g %g %g %g) = (%g %g %g) X (%g %g %g)\n",

-                      result[0], result[1], result[2], result[3],

-                      a[0], a[1], a[2], b[0], b[1], b[2]);

-            }

-         }

-         break;

-      case OPCODE_X2D:         /* 2-D matrix transform */

-         {

-            GLfloat a[4], b[4], c[4], result[4];

-            fetch_vector4(&inst->SrcReg[0], machine, a);

-            fetch_vector4(&inst->SrcReg[1], machine, b);

-            fetch_vector4(&inst->SrcReg[2], machine, c);

-            result[0] = a[0] + b[0] * c[0] + b[1] * c[1];

-            result[1] = a[1] + b[0] * c[2] + b[1] * c[3];

-            result[2] = a[2] + b[0] * c[0] + b[1] * c[1];

-            result[3] = a[3] + b[0] * c[2] + b[1] * c[3];

-            store_vector4(inst, machine, result);

-         }

-         break;

-      case OPCODE_PRINT:

-         {

-            if (inst->SrcReg[0].File != PROGRAM_UNDEFINED) {

-               GLfloat a[4];

-               fetch_vector4(&inst->SrcReg[0], machine, a);

-               printf("%s%g, %g, %g, %g\n", (const char *) inst->Data,

-                            a[0], a[1], a[2], a[3]);

-            }

-            else {

-               printf("%s\n", (const char *) inst->Data);

-            }

-         }

-         break;

-      case OPCODE_END:

-         return GL_TRUE;

-      default:

-         _mesa_problem(ctx, "Bad opcode %d in _mesa_execute_program",

-                       inst->Opcode);

-         return GL_TRUE;        /* return value doesn't matter */

-      }

-

-      numExec++;

-      if (numExec > maxExec) {

-	 static GLboolean reported = GL_FALSE;

-	 if (!reported) {

-	    _mesa_problem(ctx, "Infinite loop detected in fragment program");

-	    reported = GL_TRUE;

-	 }

-         return GL_TRUE;

-      }

-

-   } /* for pc */

-

-   return GL_TRUE;

-}

+/*
+ * Mesa 3-D graphics library
+ * Version:  7.3
+ *
+ * Copyright (C) 1999-2008  Brian Paul   All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+/**
+ * \file prog_execute.c
+ * Software interpreter for vertex/fragment programs.
+ * \author Brian Paul
+ */
+
+/*
+ * NOTE: we do everything in single-precision floating point; we don't
+ * currently observe the single/half/fixed-precision qualifiers.
+ *
+ */
+
+
+#include "main/glheader.h"
+#include "main/colormac.h"
+#include "main/macros.h"
+#include "prog_execute.h"
+#include "prog_instruction.h"
+#include "prog_parameter.h"
+#include "prog_print.h"
+#include "prog_noise.h"
+
+
+/* debug predicate */
+#define DEBUG_PROG 0
+
+
+/**
+ * Set x to positive or negative infinity.
+ */
+#if defined(USE_IEEE) || defined(_WIN32)
+#define SET_POS_INFINITY(x)                  \
+   do {                                      \
+         fi_type fi;                         \
+         fi.i = 0x7F800000;                  \
+         x = fi.f;                           \
+   } while (0)
+#define SET_NEG_INFINITY(x)                  \
+   do {                                      \
+         fi_type fi;                         \
+         fi.i = 0xFF800000;                  \
+         x = fi.f;                           \
+   } while (0)
+#elif defined(VMS)
+#define SET_POS_INFINITY(x)  x = __MAXFLOAT
+#define SET_NEG_INFINITY(x)  x = -__MAXFLOAT
+#else
+#define SET_POS_INFINITY(x)  x = (GLfloat) HUGE_VAL
+#define SET_NEG_INFINITY(x)  x = (GLfloat) -HUGE_VAL
+#endif
+
+#define SET_FLOAT_BITS(x, bits) ((fi_type *) (void *) &(x))->i = bits
+
+
+static const GLfloat ZeroVec[4] = { 0.0F, 0.0F, 0.0F, 0.0F };
+
+
+
+/**
+ * Return TRUE for +0 and other positive values, FALSE otherwise.
+ * Used for RCC opcode.
+ */
+static INLINE GLboolean
+positive(float x)
+{
+   fi_type fi;
+   fi.f = x;
+   if (fi.i & 0x80000000)
+      return GL_FALSE;
+   return GL_TRUE;
+}
+
+
+
+/**
+ * Return a pointer to the 4-element float vector specified by the given
+ * source register.
+ */
+static INLINE const GLfloat *
+get_src_register_pointer(const struct prog_src_register *source,
+                         const struct gl_program_machine *machine)
+{
+   const struct gl_program *prog = machine->CurProgram;
+   GLint reg = source->Index;
+
+   if (source->RelAddr) {
+      /* add address register value to src index/offset */
+      reg += machine->AddressReg[0][0];
+      if (reg < 0) {
+         return ZeroVec;
+      }
+   }
+
+   switch (source->File) {
+   case PROGRAM_TEMPORARY:
+      if (reg >= MAX_PROGRAM_TEMPS)
+         return ZeroVec;
+      return machine->Temporaries[reg];
+
+   case PROGRAM_INPUT:
+      if (prog->Target == GL_VERTEX_PROGRAM_ARB) {
+         if (reg >= VERT_ATTRIB_MAX)
+            return ZeroVec;
+         return machine->VertAttribs[reg];
+      }
+      else {
+         if (reg >= FRAG_ATTRIB_MAX)
+            return ZeroVec;
+         return machine->Attribs[reg][machine->CurElement];
+      }
+
+   case PROGRAM_OUTPUT:
+      if (reg >= MAX_PROGRAM_OUTPUTS)
+         return ZeroVec;
+      return machine->Outputs[reg];
+
+   case PROGRAM_LOCAL_PARAM:
+      if (reg >= MAX_PROGRAM_LOCAL_PARAMS)
+         return ZeroVec;
+      return machine->CurProgram->LocalParams[reg];
+
+   case PROGRAM_ENV_PARAM:
+      if (reg >= MAX_PROGRAM_ENV_PARAMS)
+         return ZeroVec;
+      return machine->EnvParams[reg];
+
+   case PROGRAM_STATE_VAR:
+      /* Fallthrough */
+   case PROGRAM_CONSTANT:
+      /* Fallthrough */
+   case PROGRAM_UNIFORM:
+      /* Fallthrough */
+   case PROGRAM_NAMED_PARAM:
+      if (reg >= (GLint) prog->Parameters->NumParameters)
+         return ZeroVec;
+      return (GLfloat *) prog->Parameters->ParameterValues[reg];
+
+   case PROGRAM_SYSTEM_VALUE:
+      assert(reg < Elements(machine->SystemValues));
+      return machine->SystemValues[reg];
+
+   default:
+      _mesa_problem(NULL,
+         "Invalid src register file %d in get_src_register_pointer()",
+         source->File);
+      return NULL;
+   }
+}
+
+
+/**
+ * Return a pointer to the 4-element float vector specified by the given
+ * destination register.
+ */
+static INLINE GLfloat *
+get_dst_register_pointer(const struct prog_dst_register *dest,
+                         struct gl_program_machine *machine)
+{
+   static GLfloat dummyReg[4];
+   GLint reg = dest->Index;
+
+   if (dest->RelAddr) {
+      /* add address register value to src index/offset */
+      reg += machine->AddressReg[0][0];
+      if (reg < 0) {
+         return dummyReg;
+      }
+   }
+
+   switch (dest->File) {
+   case PROGRAM_TEMPORARY:
+      if (reg >= MAX_PROGRAM_TEMPS)
+         return dummyReg;
+      return machine->Temporaries[reg];
+
+   case PROGRAM_OUTPUT:
+      if (reg >= MAX_PROGRAM_OUTPUTS)
+         return dummyReg;
+      return machine->Outputs[reg];
+
+   case PROGRAM_WRITE_ONLY:
+      return dummyReg;
+
+   default:
+      _mesa_problem(NULL,
+         "Invalid dest register file %d in get_dst_register_pointer()",
+         dest->File);
+      return NULL;
+   }
+}
+
+
+
+/**
+ * Fetch a 4-element float vector from the given source register.
+ * Apply swizzling and negating as needed.
+ */
+static void
+fetch_vector4(const struct prog_src_register *source,
+              const struct gl_program_machine *machine, GLfloat result[4])
+{
+   const GLfloat *src = get_src_register_pointer(source, machine);
+   ASSERT(src);
+
+   if (source->Swizzle == SWIZZLE_NOOP) {
+      /* no swizzling */
+      COPY_4V(result, src);
+   }
+   else {
+      ASSERT(GET_SWZ(source->Swizzle, 0) <= 3);
+      ASSERT(GET_SWZ(source->Swizzle, 1) <= 3);
+      ASSERT(GET_SWZ(source->Swizzle, 2) <= 3);
+      ASSERT(GET_SWZ(source->Swizzle, 3) <= 3);
+      result[0] = src[GET_SWZ(source->Swizzle, 0)];
+      result[1] = src[GET_SWZ(source->Swizzle, 1)];
+      result[2] = src[GET_SWZ(source->Swizzle, 2)];
+      result[3] = src[GET_SWZ(source->Swizzle, 3)];
+   }
+
+   if (source->Abs) {
+      result[0] = FABSF(result[0]);
+      result[1] = FABSF(result[1]);
+      result[2] = FABSF(result[2]);
+      result[3] = FABSF(result[3]);
+   }
+   if (source->Negate) {
+      ASSERT(source->Negate == NEGATE_XYZW);
+      result[0] = -result[0];
+      result[1] = -result[1];
+      result[2] = -result[2];
+      result[3] = -result[3];
+   }
+
+#ifdef NAN_CHECK
+   assert(!IS_INF_OR_NAN(result[0]));
+   assert(!IS_INF_OR_NAN(result[0]));
+   assert(!IS_INF_OR_NAN(result[0]));
+   assert(!IS_INF_OR_NAN(result[0]));
+#endif
+}
+
+
+/**
+ * Fetch a 4-element uint vector from the given source register.
+ * Apply swizzling but not negation/abs.
+ */
+static void
+fetch_vector4ui(const struct prog_src_register *source,
+                const struct gl_program_machine *machine, GLuint result[4])
+{
+   const GLuint *src = (GLuint *) get_src_register_pointer(source, machine);
+   ASSERT(src);
+
+   if (source->Swizzle == SWIZZLE_NOOP) {
+      /* no swizzling */
+      COPY_4V(result, src);
+   }
+   else {
+      ASSERT(GET_SWZ(source->Swizzle, 0) <= 3);
+      ASSERT(GET_SWZ(source->Swizzle, 1) <= 3);
+      ASSERT(GET_SWZ(source->Swizzle, 2) <= 3);
+      ASSERT(GET_SWZ(source->Swizzle, 3) <= 3);
+      result[0] = src[GET_SWZ(source->Swizzle, 0)];
+      result[1] = src[GET_SWZ(source->Swizzle, 1)];
+      result[2] = src[GET_SWZ(source->Swizzle, 2)];
+      result[3] = src[GET_SWZ(source->Swizzle, 3)];
+   }
+
+   /* Note: no Negate or Abs here */
+}
+
+
+
+/**
+ * Fetch the derivative with respect to X or Y for the given register.
+ * XXX this currently only works for fragment program input attribs.
+ */
+static void
+fetch_vector4_deriv(struct gl_context * ctx,
+                    const struct prog_src_register *source,
+                    const struct gl_program_machine *machine,
+                    char xOrY, GLfloat result[4])
+{
+   if (source->File == PROGRAM_INPUT &&
+       source->Index < (GLint) machine->NumDeriv) {
+      const GLint col = machine->CurElement;
+      const GLfloat w = machine->Attribs[FRAG_ATTRIB_WPOS][col][3];
+      const GLfloat invQ = 1.0f / w;
+      GLfloat deriv[4];
+
+      if (xOrY == 'X') {
+         deriv[0] = machine->DerivX[source->Index][0] * invQ;
+         deriv[1] = machine->DerivX[source->Index][1] * invQ;
+         deriv[2] = machine->DerivX[source->Index][2] * invQ;
+         deriv[3] = machine->DerivX[source->Index][3] * invQ;
+      }
+      else {
+         deriv[0] = machine->DerivY[source->Index][0] * invQ;
+         deriv[1] = machine->DerivY[source->Index][1] * invQ;
+         deriv[2] = machine->DerivY[source->Index][2] * invQ;
+         deriv[3] = machine->DerivY[source->Index][3] * invQ;
+      }
+
+      result[0] = deriv[GET_SWZ(source->Swizzle, 0)];
+      result[1] = deriv[GET_SWZ(source->Swizzle, 1)];
+      result[2] = deriv[GET_SWZ(source->Swizzle, 2)];
+      result[3] = deriv[GET_SWZ(source->Swizzle, 3)];
+      
+      if (source->Abs) {
+         result[0] = FABSF(result[0]);
+         result[1] = FABSF(result[1]);
+         result[2] = FABSF(result[2]);
+         result[3] = FABSF(result[3]);
+      }
+      if (source->Negate) {
+         ASSERT(source->Negate == NEGATE_XYZW);
+         result[0] = -result[0];
+         result[1] = -result[1];
+         result[2] = -result[2];
+         result[3] = -result[3];
+      }
+   }
+   else {
+      ASSIGN_4V(result, 0.0, 0.0, 0.0, 0.0);
+   }
+}
+
+
+/**
+ * As above, but only return result[0] element.
+ */
+static void
+fetch_vector1(const struct prog_src_register *source,
+              const struct gl_program_machine *machine, GLfloat result[4])
+{
+   const GLfloat *src = get_src_register_pointer(source, machine);
+   ASSERT(src);
+
+   result[0] = src[GET_SWZ(source->Swizzle, 0)];
+
+   if (source->Abs) {
+      result[0] = FABSF(result[0]);
+   }
+   if (source->Negate) {
+      result[0] = -result[0];
+   }
+}
+
+
+static GLuint
+fetch_vector1ui(const struct prog_src_register *source,
+                const struct gl_program_machine *machine)
+{
+   const GLuint *src = (GLuint *) get_src_register_pointer(source, machine);
+   return src[GET_SWZ(source->Swizzle, 0)];
+}
+
+
+/**
+ * Fetch texel from texture.  Use partial derivatives when possible.
+ */
+static INLINE void
+fetch_texel(struct gl_context *ctx,
+            const struct gl_program_machine *machine,
+            const struct prog_instruction *inst,
+            const GLfloat texcoord[4], GLfloat lodBias,
+            GLfloat color[4])
+{
+   const GLuint unit = machine->Samplers[inst->TexSrcUnit];
+
+   /* Note: we only have the right derivatives for fragment input attribs.
+    */
+   if (machine->NumDeriv > 0 &&
+       inst->SrcReg[0].File == PROGRAM_INPUT &&
+       inst->SrcReg[0].Index == FRAG_ATTRIB_TEX0 + inst->TexSrcUnit) {
+      /* simple texture fetch for which we should have derivatives */
+      GLuint attr = inst->SrcReg[0].Index;
+      machine->FetchTexelDeriv(ctx, texcoord,
+                               machine->DerivX[attr],
+                               machine->DerivY[attr],
+                               lodBias, unit, color);
+   }
+   else {
+      machine->FetchTexelLod(ctx, texcoord, lodBias, unit, color);
+   }
+}
+
+
+/**
+ * Test value against zero and return GT, LT, EQ or UN if NaN.
+ */
+static INLINE GLuint
+generate_cc(float value)
+{
+   if (value != value)
+      return COND_UN;           /* NaN */
+   if (value > 0.0F)
+      return COND_GT;
+   if (value < 0.0F)
+      return COND_LT;
+   return COND_EQ;
+}
+
+
+/**
+ * Test if the ccMaskRule is satisfied by the given condition code.
+ * Used to mask destination writes according to the current condition code.
+ */
+static INLINE GLboolean
+test_cc(GLuint condCode, GLuint ccMaskRule)
+{
+   switch (ccMaskRule) {
+   case COND_EQ: return (condCode == COND_EQ);
+   case COND_NE: return (condCode != COND_EQ);
+   case COND_LT: return (condCode == COND_LT);
+   case COND_GE: return (condCode == COND_GT || condCode == COND_EQ);
+   case COND_LE: return (condCode == COND_LT || condCode == COND_EQ);
+   case COND_GT: return (condCode == COND_GT);
+   case COND_TR: return GL_TRUE;
+   case COND_FL: return GL_FALSE;
+   default:      return GL_TRUE;
+   }
+}
+
+
+/**
+ * Evaluate the 4 condition codes against a predicate and return GL_TRUE
+ * or GL_FALSE to indicate result.
+ */
+static INLINE GLboolean
+eval_condition(const struct gl_program_machine *machine,
+               const struct prog_instruction *inst)
+{
+   const GLuint swizzle = inst->DstReg.CondSwizzle;
+   const GLuint condMask = inst->DstReg.CondMask;
+   if (test_cc(machine->CondCodes[GET_SWZ(swizzle, 0)], condMask) ||
+       test_cc(machine->CondCodes[GET_SWZ(swizzle, 1)], condMask) ||
+       test_cc(machine->CondCodes[GET_SWZ(swizzle, 2)], condMask) ||
+       test_cc(machine->CondCodes[GET_SWZ(swizzle, 3)], condMask)) {
+      return GL_TRUE;
+   }
+   else {
+      return GL_FALSE;
+   }
+}
+
+
+
+/**
+ * Store 4 floats into a register.  Observe the instructions saturate and
+ * set-condition-code flags.
+ */
+static void
+store_vector4(const struct prog_instruction *inst,
+              struct gl_program_machine *machine, const GLfloat value[4])
+{
+   const struct prog_dst_register *dstReg = &(inst->DstReg);
+   const GLboolean clamp = inst->SaturateMode == SATURATE_ZERO_ONE;
+   GLuint writeMask = dstReg->WriteMask;
+   GLfloat clampedValue[4];
+   GLfloat *dst = get_dst_register_pointer(dstReg, machine);
+
+#if 0
+   if (value[0] > 1.0e10 ||
+       IS_INF_OR_NAN(value[0]) ||
+       IS_INF_OR_NAN(value[1]) ||
+       IS_INF_OR_NAN(value[2]) || IS_INF_OR_NAN(value[3]))
+      printf("store %g %g %g %g\n", value[0], value[1], value[2], value[3]);
+#endif
+
+   if (clamp) {
+      clampedValue[0] = CLAMP(value[0], 0.0F, 1.0F);
+      clampedValue[1] = CLAMP(value[1], 0.0F, 1.0F);
+      clampedValue[2] = CLAMP(value[2], 0.0F, 1.0F);
+      clampedValue[3] = CLAMP(value[3], 0.0F, 1.0F);
+      value = clampedValue;
+   }
+
+   if (dstReg->CondMask != COND_TR) {
+      /* condition codes may turn off some writes */
+      if (writeMask & WRITEMASK_X) {
+         if (!test_cc(machine->CondCodes[GET_SWZ(dstReg->CondSwizzle, 0)],
+                      dstReg->CondMask))
+            writeMask &= ~WRITEMASK_X;
+      }
+      if (writeMask & WRITEMASK_Y) {
+         if (!test_cc(machine->CondCodes[GET_SWZ(dstReg->CondSwizzle, 1)],
+                      dstReg->CondMask))
+            writeMask &= ~WRITEMASK_Y;
+      }
+      if (writeMask & WRITEMASK_Z) {
+         if (!test_cc(machine->CondCodes[GET_SWZ(dstReg->CondSwizzle, 2)],
+                      dstReg->CondMask))
+            writeMask &= ~WRITEMASK_Z;
+      }
+      if (writeMask & WRITEMASK_W) {
+         if (!test_cc(machine->CondCodes[GET_SWZ(dstReg->CondSwizzle, 3)],
+                      dstReg->CondMask))
+            writeMask &= ~WRITEMASK_W;
+      }
+   }
+
+#ifdef NAN_CHECK
+   assert(!IS_INF_OR_NAN(value[0]));
+   assert(!IS_INF_OR_NAN(value[0]));
+   assert(!IS_INF_OR_NAN(value[0]));
+   assert(!IS_INF_OR_NAN(value[0]));
+#endif
+
+   if (writeMask & WRITEMASK_X)
+      dst[0] = value[0];
+   if (writeMask & WRITEMASK_Y)
+      dst[1] = value[1];
+   if (writeMask & WRITEMASK_Z)
+      dst[2] = value[2];
+   if (writeMask & WRITEMASK_W)
+      dst[3] = value[3];
+
+   if (inst->CondUpdate) {
+      if (writeMask & WRITEMASK_X)
+         machine->CondCodes[0] = generate_cc(value[0]);
+      if (writeMask & WRITEMASK_Y)
+         machine->CondCodes[1] = generate_cc(value[1]);
+      if (writeMask & WRITEMASK_Z)
+         machine->CondCodes[2] = generate_cc(value[2]);
+      if (writeMask & WRITEMASK_W)
+         machine->CondCodes[3] = generate_cc(value[3]);
+#if DEBUG_PROG
+      printf("CondCodes=(%s,%s,%s,%s) for:\n",
+             _mesa_condcode_string(machine->CondCodes[0]),
+             _mesa_condcode_string(machine->CondCodes[1]),
+             _mesa_condcode_string(machine->CondCodes[2]),
+             _mesa_condcode_string(machine->CondCodes[3]));
+#endif
+   }
+}
+
+
+/**
+ * Store 4 uints into a register.  Observe the set-condition-code flags.
+ */
+static void
+store_vector4ui(const struct prog_instruction *inst,
+                struct gl_program_machine *machine, const GLuint value[4])
+{
+   const struct prog_dst_register *dstReg = &(inst->DstReg);
+   GLuint writeMask = dstReg->WriteMask;
+   GLuint *dst = (GLuint *) get_dst_register_pointer(dstReg, machine);
+
+   if (dstReg->CondMask != COND_TR) {
+      /* condition codes may turn off some writes */
+      if (writeMask & WRITEMASK_X) {
+         if (!test_cc(machine->CondCodes[GET_SWZ(dstReg->CondSwizzle, 0)],
+                      dstReg->CondMask))
+            writeMask &= ~WRITEMASK_X;
+      }
+      if (writeMask & WRITEMASK_Y) {
+         if (!test_cc(machine->CondCodes[GET_SWZ(dstReg->CondSwizzle, 1)],
+                      dstReg->CondMask))
+            writeMask &= ~WRITEMASK_Y;
+      }
+      if (writeMask & WRITEMASK_Z) {
+         if (!test_cc(machine->CondCodes[GET_SWZ(dstReg->CondSwizzle, 2)],
+                      dstReg->CondMask))
+            writeMask &= ~WRITEMASK_Z;
+      }
+      if (writeMask & WRITEMASK_W) {
+         if (!test_cc(machine->CondCodes[GET_SWZ(dstReg->CondSwizzle, 3)],
+                      dstReg->CondMask))
+            writeMask &= ~WRITEMASK_W;
+      }
+   }
+
+   if (writeMask & WRITEMASK_X)
+      dst[0] = value[0];
+   if (writeMask & WRITEMASK_Y)
+      dst[1] = value[1];
+   if (writeMask & WRITEMASK_Z)
+      dst[2] = value[2];
+   if (writeMask & WRITEMASK_W)
+      dst[3] = value[3];
+
+   if (inst->CondUpdate) {
+      if (writeMask & WRITEMASK_X)
+         machine->CondCodes[0] = generate_cc((float)value[0]);
+      if (writeMask & WRITEMASK_Y)
+         machine->CondCodes[1] = generate_cc((float)value[1]);
+      if (writeMask & WRITEMASK_Z)
+         machine->CondCodes[2] = generate_cc((float)value[2]);
+      if (writeMask & WRITEMASK_W)
+         machine->CondCodes[3] = generate_cc((float)value[3]);
+#if DEBUG_PROG
+      printf("CondCodes=(%s,%s,%s,%s) for:\n",
+             _mesa_condcode_string(machine->CondCodes[0]),
+             _mesa_condcode_string(machine->CondCodes[1]),
+             _mesa_condcode_string(machine->CondCodes[2]),
+             _mesa_condcode_string(machine->CondCodes[3]));
+#endif
+   }
+}
+
+
+
+/**
+ * Execute the given vertex/fragment program.
+ *
+ * \param ctx  rendering context
+ * \param program  the program to execute
+ * \param machine  machine state (must be initialized)
+ * \return GL_TRUE if program completed or GL_FALSE if program executed KIL.
+ */
+GLboolean
+_mesa_execute_program(struct gl_context * ctx,
+                      const struct gl_program *program,
+                      struct gl_program_machine *machine)
+{
+   const GLuint numInst = program->NumInstructions;
+   const GLuint maxExec = 10000;
+   GLuint pc, numExec = 0;
+
+   machine->CurProgram = program;
+
+   if (DEBUG_PROG) {
+      printf("execute program %u --------------------\n", program->Id);
+   }
+
+   if (program->Target == GL_VERTEX_PROGRAM_ARB) {
+      machine->EnvParams = ctx->VertexProgram.Parameters;
+   }
+   else {
+      machine->EnvParams = ctx->FragmentProgram.Parameters;
+   }
+
+   for (pc = 0; pc < numInst; pc++) {
+      const struct prog_instruction *inst = program->Instructions + pc;
+
+      if (DEBUG_PROG) {
+         _mesa_print_instruction(inst);
+      }
+
+      switch (inst->Opcode) {
+      case OPCODE_ABS:
+         {
+            GLfloat a[4], result[4];
+            fetch_vector4(&inst->SrcReg[0], machine, a);
+            result[0] = FABSF(a[0]);
+            result[1] = FABSF(a[1]);
+            result[2] = FABSF(a[2]);
+            result[3] = FABSF(a[3]);
+            store_vector4(inst, machine, result);
+         }
+         break;
+      case OPCODE_ADD:
+         {
+            GLfloat a[4], b[4], result[4];
+            fetch_vector4(&inst->SrcReg[0], machine, a);
+            fetch_vector4(&inst->SrcReg[1], machine, b);
+            result[0] = a[0] + b[0];
+            result[1] = a[1] + b[1];
+            result[2] = a[2] + b[2];
+            result[3] = a[3] + b[3];
+            store_vector4(inst, machine, result);
+            if (DEBUG_PROG) {
+               printf("ADD (%g %g %g %g) = (%g %g %g %g) + (%g %g %g %g)\n",
+                      result[0], result[1], result[2], result[3],
+                      a[0], a[1], a[2], a[3], b[0], b[1], b[2], b[3]);
+            }
+         }
+         break;
+      case OPCODE_AND:     /* bitwise AND */
+         {
+            GLuint a[4], b[4], result[4];
+            fetch_vector4ui(&inst->SrcReg[0], machine, a);
+            fetch_vector4ui(&inst->SrcReg[1], machine, b);
+            result[0] = a[0] & b[0];
+            result[1] = a[1] & b[1];
+            result[2] = a[2] & b[2];
+            result[3] = a[3] & b[3];
+            store_vector4ui(inst, machine, result);
+         }
+         break;
+      case OPCODE_ARL:
+         {
+            GLfloat t[4];
+            fetch_vector4(&inst->SrcReg[0], machine, t);
+            machine->AddressReg[0][0] = IFLOOR(t[0]);
+            if (DEBUG_PROG) {
+               printf("ARL %d\n", machine->AddressReg[0][0]);
+            }
+         }
+         break;
+      case OPCODE_BGNLOOP:
+         /* no-op */
+         ASSERT(program->Instructions[inst->BranchTarget].Opcode
+                == OPCODE_ENDLOOP);
+         break;
+      case OPCODE_ENDLOOP:
+         /* subtract 1 here since pc is incremented by for(pc) loop */
+         ASSERT(program->Instructions[inst->BranchTarget].Opcode
+                == OPCODE_BGNLOOP);
+         pc = inst->BranchTarget - 1;   /* go to matching BNGLOOP */
+         break;
+      case OPCODE_BGNSUB:      /* begin subroutine */
+         break;
+      case OPCODE_ENDSUB:      /* end subroutine */
+         break;
+      case OPCODE_BRA:         /* branch (conditional) */
+         if (eval_condition(machine, inst)) {
+            /* take branch */
+            /* Subtract 1 here since we'll do pc++ below */
+            pc = inst->BranchTarget - 1;
+         }
+         break;
+      case OPCODE_BRK:         /* break out of loop (conditional) */
+         ASSERT(program->Instructions[inst->BranchTarget].Opcode
+                == OPCODE_ENDLOOP);
+         if (eval_condition(machine, inst)) {
+            /* break out of loop */
+            /* pc++ at end of for-loop will put us after the ENDLOOP inst */
+            pc = inst->BranchTarget;
+         }
+         break;
+      case OPCODE_CONT:        /* continue loop (conditional) */
+         ASSERT(program->Instructions[inst->BranchTarget].Opcode
+                == OPCODE_ENDLOOP);
+         if (eval_condition(machine, inst)) {
+            /* continue at ENDLOOP */
+            /* Subtract 1 here since we'll do pc++ at end of for-loop */
+            pc = inst->BranchTarget - 1;
+         }
+         break;
+      case OPCODE_CAL:         /* Call subroutine (conditional) */
+         if (eval_condition(machine, inst)) {
+            /* call the subroutine */
+            if (machine->StackDepth >= MAX_PROGRAM_CALL_DEPTH) {
+               return GL_TRUE;  /* Per GL_NV_vertex_program2 spec */
+            }
+            machine->CallStack[machine->StackDepth++] = pc + 1; /* next inst */
+            /* Subtract 1 here since we'll do pc++ at end of for-loop */
+            pc = inst->BranchTarget - 1;
+         }
+         break;
+      case OPCODE_CMP:
+         {
+            GLfloat a[4], b[4], c[4], result[4];
+            fetch_vector4(&inst->SrcReg[0], machine, a);
+            fetch_vector4(&inst->SrcReg[1], machine, b);
+            fetch_vector4(&inst->SrcReg[2], machine, c);
+            result[0] = a[0] < 0.0F ? b[0] : c[0];
+            result[1] = a[1] < 0.0F ? b[1] : c[1];
+            result[2] = a[2] < 0.0F ? b[2] : c[2];
+            result[3] = a[3] < 0.0F ? b[3] : c[3];
+            store_vector4(inst, machine, result);
+            if (DEBUG_PROG) {
+               printf("CMP (%g %g %g %g) = (%g %g %g %g) < 0 ? (%g %g %g %g) : (%g %g %g %g)\n",
+                      result[0], result[1], result[2], result[3],
+                      a[0], a[1], a[2], a[3],
+                      b[0], b[1], b[2], b[3],
+                      c[0], c[1], c[2], c[3]);
+            }
+         }
+         break;
+      case OPCODE_COS:
+         {
+            GLfloat a[4], result[4];
+            fetch_vector1(&inst->SrcReg[0], machine, a);
+            result[0] = result[1] = result[2] = result[3]
+               = (GLfloat) cos(a[0]);
+            store_vector4(inst, machine, result);
+         }
+         break;
+      case OPCODE_DDX:         /* Partial derivative with respect to X */
+         {
+            GLfloat result[4];
+            fetch_vector4_deriv(ctx, &inst->SrcReg[0], machine,
+                                'X', result);
+            store_vector4(inst, machine, result);
+         }
+         break;
+      case OPCODE_DDY:         /* Partial derivative with respect to Y */
+         {
+            GLfloat result[4];
+            fetch_vector4_deriv(ctx, &inst->SrcReg[0], machine,
+                                'Y', result);
+            store_vector4(inst, machine, result);
+         }
+         break;
+      case OPCODE_DP2:
+         {
+            GLfloat a[4], b[4], result[4];
+            fetch_vector4(&inst->SrcReg[0], machine, a);
+            fetch_vector4(&inst->SrcReg[1], machine, b);
+            result[0] = result[1] = result[2] = result[3] = DOT2(a, b);
+            store_vector4(inst, machine, result);
+            if (DEBUG_PROG) {
+               printf("DP2 %g = (%g %g) . (%g %g)\n",
+                      result[0], a[0], a[1], b[0], b[1]);
+            }
+         }
+         break;
+      case OPCODE_DP2A:
+         {
+            GLfloat a[4], b[4], c, result[4];
+            fetch_vector4(&inst->SrcReg[0], machine, a);
+            fetch_vector4(&inst->SrcReg[1], machine, b);
+            fetch_vector1(&inst->SrcReg[1], machine, &c);
+            result[0] = result[1] = result[2] = result[3] = DOT2(a, b) + c;
+            store_vector4(inst, machine, result);
+            if (DEBUG_PROG) {
+               printf("DP2A %g = (%g %g) . (%g %g) + %g\n",
+                      result[0], a[0], a[1], b[0], b[1], c);
+            }
+         }
+         break;
+      case OPCODE_DP3:
+         {
+            GLfloat a[4], b[4], result[4];
+            fetch_vector4(&inst->SrcReg[0], machine, a);
+            fetch_vector4(&inst->SrcReg[1], machine, b);
+            result[0] = result[1] = result[2] = result[3] = DOT3(a, b);
+            store_vector4(inst, machine, result);
+            if (DEBUG_PROG) {
+               printf("DP3 %g = (%g %g %g) . (%g %g %g)\n",
+                      result[0], a[0], a[1], a[2], b[0], b[1], b[2]);
+            }
+         }
+         break;
+      case OPCODE_DP4:
+         {
+            GLfloat a[4], b[4], result[4];
+            fetch_vector4(&inst->SrcReg[0], machine, a);
+            fetch_vector4(&inst->SrcReg[1], machine, b);
+            result[0] = result[1] = result[2] = result[3] = DOT4(a, b);
+            store_vector4(inst, machine, result);
+            if (DEBUG_PROG) {
+               printf("DP4 %g = (%g, %g %g %g) . (%g, %g %g %g)\n",
+                      result[0], a[0], a[1], a[2], a[3],
+                      b[0], b[1], b[2], b[3]);
+            }
+         }
+         break;
+      case OPCODE_DPH:
+         {
+            GLfloat a[4], b[4], result[4];
+            fetch_vector4(&inst->SrcReg[0], machine, a);
+            fetch_vector4(&inst->SrcReg[1], machine, b);
+            result[0] = result[1] = result[2] = result[3] = DOT3(a, b) + b[3];
+            store_vector4(inst, machine, result);
+         }
+         break;
+      case OPCODE_DST:         /* Distance vector */
+         {
+            GLfloat a[4], b[4], result[4];
+            fetch_vector4(&inst->SrcReg[0], machine, a);
+            fetch_vector4(&inst->SrcReg[1], machine, b);
+            result[0] = 1.0F;
+            result[1] = a[1] * b[1];
+            result[2] = a[2];
+            result[3] = b[3];
+            store_vector4(inst, machine, result);
+         }
+         break;
+      case OPCODE_EXP:
+         {
+            GLfloat t[4], q[4], floor_t0;
+            fetch_vector1(&inst->SrcReg[0], machine, t);
+            floor_t0 = FLOORF(t[0]);
+            if (floor_t0 > FLT_MAX_EXP) {
+               SET_POS_INFINITY(q[0]);
+               SET_POS_INFINITY(q[2]);
+            }
+            else if (floor_t0 < FLT_MIN_EXP) {
+               q[0] = 0.0F;
+               q[2] = 0.0F;
+            }
+            else {
+               q[0] = LDEXPF(1.0, (int) floor_t0);
+               /* Note: GL_NV_vertex_program expects 
+                * result.z = result.x * APPX(result.y)
+                * We do what the ARB extension says.
+                */
+               q[2] = (GLfloat) pow(2.0, t[0]);
+            }
+            q[1] = t[0] - floor_t0;
+            q[3] = 1.0F;
+            store_vector4( inst, machine, q );
+         }
+         break;
+      case OPCODE_EX2:         /* Exponential base 2 */
+         {
+            GLfloat a[4], result[4], val;
+            fetch_vector1(&inst->SrcReg[0], machine, a);
+            val = (GLfloat) pow(2.0, a[0]);
+            /*
+            if (IS_INF_OR_NAN(val))
+               val = 1.0e10;
+            */
+            result[0] = result[1] = result[2] = result[3] = val;
+            store_vector4(inst, machine, result);
+         }
+         break;
+      case OPCODE_FLR:
+         {
+            GLfloat a[4], result[4];
+            fetch_vector4(&inst->SrcReg[0], machine, a);
+            result[0] = FLOORF(a[0]);
+            result[1] = FLOORF(a[1]);
+            result[2] = FLOORF(a[2]);
+            result[3] = FLOORF(a[3]);
+            store_vector4(inst, machine, result);
+         }
+         break;
+      case OPCODE_FRC:
+         {
+            GLfloat a[4], result[4];
+            fetch_vector4(&inst->SrcReg[0], machine, a);
+            result[0] = a[0] - FLOORF(a[0]);
+            result[1] = a[1] - FLOORF(a[1]);
+            result[2] = a[2] - FLOORF(a[2]);
+            result[3] = a[3] - FLOORF(a[3]);
+            store_vector4(inst, machine, result);
+         }
+         break;
+      case OPCODE_IF:
+         {
+            GLboolean cond;
+            ASSERT(program->Instructions[inst->BranchTarget].Opcode
+                   == OPCODE_ELSE ||
+                   program->Instructions[inst->BranchTarget].Opcode
+                   == OPCODE_ENDIF);
+            /* eval condition */
+            if (inst->SrcReg[0].File != PROGRAM_UNDEFINED) {
+               GLfloat a[4];
+               fetch_vector1(&inst->SrcReg[0], machine, a);
+               cond = (a[0] != 0.0);
+            }
+            else {
+               cond = eval_condition(machine, inst);
+            }
+            if (DEBUG_PROG) {
+               printf("IF: %d\n", cond);
+            }
+            /* do if/else */
+            if (cond) {
+               /* do if-clause (just continue execution) */
+            }
+            else {
+               /* go to the instruction after ELSE or ENDIF */
+               assert(inst->BranchTarget >= 0);
+               pc = inst->BranchTarget;
+            }
+         }
+         break;
+      case OPCODE_ELSE:
+         /* goto ENDIF */
+         ASSERT(program->Instructions[inst->BranchTarget].Opcode
+                == OPCODE_ENDIF);
+         assert(inst->BranchTarget >= 0);
+         pc = inst->BranchTarget;
+         break;
+      case OPCODE_ENDIF:
+         /* nothing */
+         break;
+      case OPCODE_KIL_NV:      /* NV_f_p only (conditional) */
+         if (eval_condition(machine, inst)) {
+            return GL_FALSE;
+         }
+         break;
+      case OPCODE_KIL:         /* ARB_f_p only */
+         {
+            GLfloat a[4];
+            fetch_vector4(&inst->SrcReg[0], machine, a);
+            if (DEBUG_PROG) {
+               printf("KIL if (%g %g %g %g) <= 0.0\n",
+                      a[0], a[1], a[2], a[3]);
+            }
+
+            if (a[0] < 0.0F || a[1] < 0.0F || a[2] < 0.0F || a[3] < 0.0F) {
+               return GL_FALSE;
+            }
+         }
+         break;
+      case OPCODE_LG2:         /* log base 2 */
+         {
+            GLfloat a[4], result[4], val;
+            fetch_vector1(&inst->SrcReg[0], machine, a);
+	    /* The fast LOG2 macro doesn't meet the precision requirements.
+	     */
+            if (a[0] == 0.0F) {
+               val = -FLT_MAX;
+            }
+            else {
+               val = (float)(log(a[0]) * 1.442695F);
+            }
+            result[0] = result[1] = result[2] = result[3] = val;
+            store_vector4(inst, machine, result);
+         }
+         break;
+      case OPCODE_LIT:
+         {
+            const GLfloat epsilon = 1.0F / 256.0F;      /* from NV VP spec */
+            GLfloat a[4], result[4];
+            fetch_vector4(&inst->SrcReg[0], machine, a);
+            a[0] = MAX2(a[0], 0.0F);
+            a[1] = MAX2(a[1], 0.0F);
+            /* XXX ARB version clamps a[3], NV version doesn't */
+            a[3] = CLAMP(a[3], -(128.0F - epsilon), (128.0F - epsilon));
+            result[0] = 1.0F;
+            result[1] = a[0];
+            /* XXX we could probably just use pow() here */
+            if (a[0] > 0.0F) {
+               if (a[1] == 0.0 && a[3] == 0.0)
+                  result[2] = 1.0F;
+               else
+                  result[2] = (GLfloat) pow(a[1], a[3]);
+            }
+            else {
+               result[2] = 0.0F;
+            }
+            result[3] = 1.0F;
+            store_vector4(inst, machine, result);
+            if (DEBUG_PROG) {
+               printf("LIT (%g %g %g %g) : (%g %g %g %g)\n",
+                      result[0], result[1], result[2], result[3],
+                      a[0], a[1], a[2], a[3]);
+            }
+         }
+         break;
+      case OPCODE_LOG:
+         {
+            GLfloat t[4], q[4], abs_t0;
+            fetch_vector1(&inst->SrcReg[0], machine, t);
+            abs_t0 = FABSF(t[0]);
+            if (abs_t0 != 0.0F) {
+               /* Since we really can't handle infinite values on VMS
+                * like other OSes we'll use __MAXFLOAT to represent
+                * infinity.  This may need some tweaking.
+                */
+#ifdef VMS
+               if (abs_t0 == __MAXFLOAT)
+#else
+               if (IS_INF_OR_NAN(abs_t0))
+#endif
+               {
+                  SET_POS_INFINITY(q[0]);
+                  q[1] = 1.0F;
+                  SET_POS_INFINITY(q[2]);
+               }
+               else {
+                  int exponent;
+                  GLfloat mantissa = FREXPF(t[0], &exponent);
+                  q[0] = (GLfloat) (exponent - 1);
+                  q[1] = (GLfloat) (2.0 * mantissa); /* map [.5, 1) -> [1, 2) */
+
+		  /* The fast LOG2 macro doesn't meet the precision
+		   * requirements.
+		   */
+                  q[2] = (float)(log(t[0]) * 1.442695F);
+               }
+            }
+            else {
+               SET_NEG_INFINITY(q[0]);
+               q[1] = 1.0F;
+               SET_NEG_INFINITY(q[2]);
+            }
+            q[3] = 1.0;
+            store_vector4(inst, machine, q);
+         }
+         break;
+      case OPCODE_LRP:
+         {
+            GLfloat a[4], b[4], c[4], result[4];
+            fetch_vector4(&inst->SrcReg[0], machine, a);
+            fetch_vector4(&inst->SrcReg[1], machine, b);
+            fetch_vector4(&inst->SrcReg[2], machine, c);
+            result[0] = a[0] * b[0] + (1.0F - a[0]) * c[0];
+            result[1] = a[1] * b[1] + (1.0F - a[1]) * c[1];
+            result[2] = a[2] * b[2] + (1.0F - a[2]) * c[2];
+            result[3] = a[3] * b[3] + (1.0F - a[3]) * c[3];
+            store_vector4(inst, machine, result);
+            if (DEBUG_PROG) {
+               printf("LRP (%g %g %g %g) = (%g %g %g %g), "
+                      "(%g %g %g %g), (%g %g %g %g)\n",
+                      result[0], result[1], result[2], result[3],
+                      a[0], a[1], a[2], a[3],
+                      b[0], b[1], b[2], b[3], c[0], c[1], c[2], c[3]);
+            }
+         }
+         break;
+      case OPCODE_MAD:
+         {
+            GLfloat a[4], b[4], c[4], result[4];
+            fetch_vector4(&inst->SrcReg[0], machine, a);
+            fetch_vector4(&inst->SrcReg[1], machine, b);
+            fetch_vector4(&inst->SrcReg[2], machine, c);
+            result[0] = a[0] * b[0] + c[0];
+            result[1] = a[1] * b[1] + c[1];
+            result[2] = a[2] * b[2] + c[2];
+            result[3] = a[3] * b[3] + c[3];
+            store_vector4(inst, machine, result);
+            if (DEBUG_PROG) {
+               printf("MAD (%g %g %g %g) = (%g %g %g %g) * "
+                      "(%g %g %g %g) + (%g %g %g %g)\n",
+                      result[0], result[1], result[2], result[3],
+                      a[0], a[1], a[2], a[3],
+                      b[0], b[1], b[2], b[3], c[0], c[1], c[2], c[3]);
+            }
+         }
+         break;
+      case OPCODE_MAX:
+         {
+            GLfloat a[4], b[4], result[4];
+            fetch_vector4(&inst->SrcReg[0], machine, a);
+            fetch_vector4(&inst->SrcReg[1], machine, b);
+            result[0] = MAX2(a[0], b[0]);
+            result[1] = MAX2(a[1], b[1]);
+            result[2] = MAX2(a[2], b[2]);
+            result[3] = MAX2(a[3], b[3]);
+            store_vector4(inst, machine, result);
+            if (DEBUG_PROG) {
+               printf("MAX (%g %g %g %g) = (%g %g %g %g), (%g %g %g %g)\n",
+                      result[0], result[1], result[2], result[3],
+                      a[0], a[1], a[2], a[3], b[0], b[1], b[2], b[3]);
+            }
+         }
+         break;
+      case OPCODE_MIN:
+         {
+            GLfloat a[4], b[4], result[4];
+            fetch_vector4(&inst->SrcReg[0], machine, a);
+            fetch_vector4(&inst->SrcReg[1], machine, b);
+            result[0] = MIN2(a[0], b[0]);
+            result[1] = MIN2(a[1], b[1]);
+            result[2] = MIN2(a[2], b[2]);
+            result[3] = MIN2(a[3], b[3]);
+            store_vector4(inst, machine, result);
+         }
+         break;
+      case OPCODE_MOV:
+         {
+            GLfloat result[4];
+            fetch_vector4(&inst->SrcReg[0], machine, result);
+            store_vector4(inst, machine, result);
+            if (DEBUG_PROG) {
+               printf("MOV (%g %g %g %g)\n",
+                      result[0], result[1], result[2], result[3]);
+            }
+         }
+         break;
+      case OPCODE_MUL:
+         {
+            GLfloat a[4], b[4], result[4];
+            fetch_vector4(&inst->SrcReg[0], machine, a);
+            fetch_vector4(&inst->SrcReg[1], machine, b);
+            result[0] = a[0] * b[0];
+            result[1] = a[1] * b[1];
+            result[2] = a[2] * b[2];
+            result[3] = a[3] * b[3];
+            store_vector4(inst, machine, result);
+            if (DEBUG_PROG) {
+               printf("MUL (%g %g %g %g) = (%g %g %g %g) * (%g %g %g %g)\n",
+                      result[0], result[1], result[2], result[3],
+                      a[0], a[1], a[2], a[3], b[0], b[1], b[2], b[3]);
+            }
+         }
+         break;
+      case OPCODE_NOISE1:
+         {
+            GLfloat a[4], result[4];
+            fetch_vector1(&inst->SrcReg[0], machine, a);
+            result[0] =
+               result[1] =
+               result[2] =
+               result[3] = _mesa_noise1(a[0]);
+            store_vector4(inst, machine, result);
+         }
+         break;
+      case OPCODE_NOISE2:
+         {
+            GLfloat a[4], result[4];
+            fetch_vector4(&inst->SrcReg[0], machine, a);
+            result[0] =
+               result[1] =
+               result[2] = result[3] = _mesa_noise2(a[0], a[1]);
+            store_vector4(inst, machine, result);
+         }
+         break;
+      case OPCODE_NOISE3:
+         {
+            GLfloat a[4], result[4];
+            fetch_vector4(&inst->SrcReg[0], machine, a);
+            result[0] =
+               result[1] =
+               result[2] =
+               result[3] = _mesa_noise3(a[0], a[1], a[2]);
+            store_vector4(inst, machine, result);
+         }
+         break;
+      case OPCODE_NOISE4:
+         {
+            GLfloat a[4], result[4];
+            fetch_vector4(&inst->SrcReg[0], machine, a);
+            result[0] =
+               result[1] =
+               result[2] =
+               result[3] = _mesa_noise4(a[0], a[1], a[2], a[3]);
+            store_vector4(inst, machine, result);
+         }
+         break;
+      case OPCODE_NOP:
+         break;
+      case OPCODE_NOT:         /* bitwise NOT */
+         {
+            GLuint a[4], result[4];
+            fetch_vector4ui(&inst->SrcReg[0], machine, a);
+            result[0] = ~a[0];
+            result[1] = ~a[1];
+            result[2] = ~a[2];
+            result[3] = ~a[3];
+            store_vector4ui(inst, machine, result);
+         }
+         break;
+      case OPCODE_NRM3:        /* 3-component normalization */
+         {
+            GLfloat a[4], result[4];
+            GLfloat tmp;
+            fetch_vector4(&inst->SrcReg[0], machine, a);
+            tmp = a[0] * a[0] + a[1] * a[1] + a[2] * a[2];
+            if (tmp != 0.0F)
+               tmp = INV_SQRTF(tmp);
+            result[0] = tmp * a[0];
+            result[1] = tmp * a[1];
+            result[2] = tmp * a[2];
+            result[3] = 0.0;  /* undefined, but prevent valgrind warnings */
+            store_vector4(inst, machine, result);
+         }
+         break;
+      case OPCODE_NRM4:        /* 4-component normalization */
+         {
+            GLfloat a[4], result[4];
+            GLfloat tmp;
+            fetch_vector4(&inst->SrcReg[0], machine, a);
+            tmp = a[0] * a[0] + a[1] * a[1] + a[2] * a[2] + a[3] * a[3];
+            if (tmp != 0.0F)
+               tmp = INV_SQRTF(tmp);
+            result[0] = tmp * a[0];
+            result[1] = tmp * a[1];
+            result[2] = tmp * a[2];
+            result[3] = tmp * a[3];
+            store_vector4(inst, machine, result);
+         }
+         break;
+      case OPCODE_OR:          /* bitwise OR */
+         {
+            GLuint a[4], b[4], result[4];
+            fetch_vector4ui(&inst->SrcReg[0], machine, a);
+            fetch_vector4ui(&inst->SrcReg[1], machine, b);
+            result[0] = a[0] | b[0];
+            result[1] = a[1] | b[1];
+            result[2] = a[2] | b[2];
+            result[3] = a[3] | b[3];
+            store_vector4ui(inst, machine, result);
+         }
+         break;
+      case OPCODE_PK2H:        /* pack two 16-bit floats in one 32-bit float */
+         {
+            GLfloat a[4];
+            GLuint result[4];
+            GLhalfNV hx, hy;
+            fetch_vector4(&inst->SrcReg[0], machine, a);
+            hx = _mesa_float_to_half(a[0]);
+            hy = _mesa_float_to_half(a[1]);
+            result[0] =
+            result[1] =
+            result[2] =
+            result[3] = hx | (hy << 16);
+            store_vector4ui(inst, machine, result);
+         }
+         break;
+      case OPCODE_PK2US:       /* pack two GLushorts into one 32-bit float */
+         {
+            GLfloat a[4];
+            GLuint result[4], usx, usy;
+            fetch_vector4(&inst->SrcReg[0], machine, a);
+            a[0] = CLAMP(a[0], 0.0F, 1.0F);
+            a[1] = CLAMP(a[1], 0.0F, 1.0F);
+            usx = IROUND(a[0] * 65535.0F);
+            usy = IROUND(a[1] * 65535.0F);
+            result[0] =
+            result[1] =
+            result[2] =
+            result[3] = usx | (usy << 16);
+            store_vector4ui(inst, machine, result);
+         }
+         break;
+      case OPCODE_PK4B:        /* pack four GLbytes into one 32-bit float */
+         {
+            GLfloat a[4];
+            GLuint result[4], ubx, uby, ubz, ubw;
+            fetch_vector4(&inst->SrcReg[0], machine, a);
+            a[0] = CLAMP(a[0], -128.0F / 127.0F, 1.0F);
+            a[1] = CLAMP(a[1], -128.0F / 127.0F, 1.0F);
+            a[2] = CLAMP(a[2], -128.0F / 127.0F, 1.0F);
+            a[3] = CLAMP(a[3], -128.0F / 127.0F, 1.0F);
+            ubx = IROUND(127.0F * a[0] + 128.0F);
+            uby = IROUND(127.0F * a[1] + 128.0F);
+            ubz = IROUND(127.0F * a[2] + 128.0F);
+            ubw = IROUND(127.0F * a[3] + 128.0F);
+            result[0] =
+            result[1] =
+            result[2] =
+            result[3] = ubx | (uby << 8) | (ubz << 16) | (ubw << 24);
+            store_vector4ui(inst, machine, result);
+         }
+         break;
+      case OPCODE_PK4UB:       /* pack four GLubytes into one 32-bit float */
+         {
+            GLfloat a[4];
+            GLuint result[4], ubx, uby, ubz, ubw;
+            fetch_vector4(&inst->SrcReg[0], machine, a);
+            a[0] = CLAMP(a[0], 0.0F, 1.0F);
+            a[1] = CLAMP(a[1], 0.0F, 1.0F);
+            a[2] = CLAMP(a[2], 0.0F, 1.0F);
+            a[3] = CLAMP(a[3], 0.0F, 1.0F);
+            ubx = IROUND(255.0F * a[0]);
+            uby = IROUND(255.0F * a[1]);
+            ubz = IROUND(255.0F * a[2]);
+            ubw = IROUND(255.0F * a[3]);
+            result[0] =
+            result[1] =
+            result[2] =
+            result[3] = ubx | (uby << 8) | (ubz << 16) | (ubw << 24);
+            store_vector4ui(inst, machine, result);
+         }
+         break;
+      case OPCODE_POW:
+         {
+            GLfloat a[4], b[4], result[4];
+            fetch_vector1(&inst->SrcReg[0], machine, a);
+            fetch_vector1(&inst->SrcReg[1], machine, b);
+            result[0] = result[1] = result[2] = result[3]
+               = (GLfloat) pow(a[0], b[0]);
+            store_vector4(inst, machine, result);
+         }
+         break;
+      case OPCODE_RCC:  /* clamped riciprocal */
+         {
+            const float largest = 1.884467e+19, smallest = 5.42101e-20;
+            GLfloat a[4], r, result[4];
+            fetch_vector1(&inst->SrcReg[0], machine, a);
+            if (DEBUG_PROG) {
+               if (a[0] == 0)
+                  printf("RCC(0)\n");
+               else if (IS_INF_OR_NAN(a[0]))
+                  printf("RCC(inf)\n");
+            }
+            if (a[0] == 1.0F) {
+               r = 1.0F;
+            }
+            else {
+               r = 1.0F / a[0];
+            }
+            if (positive(r)) {
+               if (r > largest) {
+                  r = largest;
+               }
+               else if (r < smallest) {
+                  r = smallest;
+               }
+            }
+            else {
+               if (r < -largest) {
+                  r = -largest;
+               }
+               else if (r > -smallest) {
+                  r = -smallest;
+               }
+            }
+            result[0] = result[1] = result[2] = result[3] = r;
+            store_vector4(inst, machine, result);
+         }
+         break;
+
+      case OPCODE_RCP:
+         {
+            GLfloat a[4], result[4];
+            fetch_vector1(&inst->SrcReg[0], machine, a);
+            if (DEBUG_PROG) {
+               if (a[0] == 0)
+                  printf("RCP(0)\n");
+               else if (IS_INF_OR_NAN(a[0]))
+                  printf("RCP(inf)\n");
+            }
+            result[0] = result[1] = result[2] = result[3] = 1.0F / a[0];
+            store_vector4(inst, machine, result);
+         }
+         break;
+      case OPCODE_RET:         /* return from subroutine (conditional) */
+         if (eval_condition(machine, inst)) {
+            if (machine->StackDepth == 0) {
+               return GL_TRUE;  /* Per GL_NV_vertex_program2 spec */
+            }
+            /* subtract one because of pc++ in the for loop */
+            pc = machine->CallStack[--machine->StackDepth] - 1;
+         }
+         break;
+      case OPCODE_RFL:         /* reflection vector */
+         {
+            GLfloat axis[4], dir[4], result[4], tmpX, tmpW;
+            fetch_vector4(&inst->SrcReg[0], machine, axis);
+            fetch_vector4(&inst->SrcReg[1], machine, dir);
+            tmpW = DOT3(axis, axis);
+            tmpX = (2.0F * DOT3(axis, dir)) / tmpW;
+            result[0] = tmpX * axis[0] - dir[0];
+            result[1] = tmpX * axis[1] - dir[1];
+            result[2] = tmpX * axis[2] - dir[2];
+            /* result[3] is never written! XXX enforce in parser! */
+            store_vector4(inst, machine, result);
+         }
+         break;
+      case OPCODE_RSQ:         /* 1 / sqrt() */
+         {
+            GLfloat a[4], result[4];
+            fetch_vector1(&inst->SrcReg[0], machine, a);
+            a[0] = FABSF(a[0]);
+            result[0] = result[1] = result[2] = result[3] = INV_SQRTF(a[0]);
+            store_vector4(inst, machine, result);
+            if (DEBUG_PROG) {
+               printf("RSQ %g = 1/sqrt(|%g|)\n", result[0], a[0]);
+            }
+         }
+         break;
+      case OPCODE_SCS:         /* sine and cos */
+         {
+            GLfloat a[4], result[4];
+            fetch_vector1(&inst->SrcReg[0], machine, a);
+            result[0] = (GLfloat) cos(a[0]);
+            result[1] = (GLfloat) sin(a[0]);
+            result[2] = 0.0;    /* undefined! */
+            result[3] = 0.0;    /* undefined! */
+            store_vector4(inst, machine, result);
+         }
+         break;
+      case OPCODE_SEQ:         /* set on equal */
+         {
+            GLfloat a[4], b[4], result[4];
+            fetch_vector4(&inst->SrcReg[0], machine, a);
+            fetch_vector4(&inst->SrcReg[1], machine, b);
+            result[0] = (a[0] == b[0]) ? 1.0F : 0.0F;
+            result[1] = (a[1] == b[1]) ? 1.0F : 0.0F;
+            result[2] = (a[2] == b[2]) ? 1.0F : 0.0F;
+            result[3] = (a[3] == b[3]) ? 1.0F : 0.0F;
+            store_vector4(inst, machine, result);
+            if (DEBUG_PROG) {
+               printf("SEQ (%g %g %g %g) = (%g %g %g %g) == (%g %g %g %g)\n",
+                      result[0], result[1], result[2], result[3],
+                      a[0], a[1], a[2], a[3],
+                      b[0], b[1], b[2], b[3]);
+            }
+         }
+         break;
+      case OPCODE_SFL:         /* set false, operands ignored */
+         {
+            static const GLfloat result[4] = { 0.0F, 0.0F, 0.0F, 0.0F };
+            store_vector4(inst, machine, result);
+         }
+         break;
+      case OPCODE_SGE:         /* set on greater or equal */
+         {
+            GLfloat a[4], b[4], result[4];
+            fetch_vector4(&inst->SrcReg[0], machine, a);
+            fetch_vector4(&inst->SrcReg[1], machine, b);
+            result[0] = (a[0] >= b[0]) ? 1.0F : 0.0F;
+            result[1] = (a[1] >= b[1]) ? 1.0F : 0.0F;
+            result[2] = (a[2] >= b[2]) ? 1.0F : 0.0F;
+            result[3] = (a[3] >= b[3]) ? 1.0F : 0.0F;
+            store_vector4(inst, machine, result);
+            if (DEBUG_PROG) {
+               printf("SGE (%g %g %g %g) = (%g %g %g %g) >= (%g %g %g %g)\n",
+                      result[0], result[1], result[2], result[3],
+                      a[0], a[1], a[2], a[3],
+                      b[0], b[1], b[2], b[3]);
+            }
+         }
+         break;
+      case OPCODE_SGT:         /* set on greater */
+         {
+            GLfloat a[4], b[4], result[4];
+            fetch_vector4(&inst->SrcReg[0], machine, a);
+            fetch_vector4(&inst->SrcReg[1], machine, b);
+            result[0] = (a[0] > b[0]) ? 1.0F : 0.0F;
+            result[1] = (a[1] > b[1]) ? 1.0F : 0.0F;
+            result[2] = (a[2] > b[2]) ? 1.0F : 0.0F;
+            result[3] = (a[3] > b[3]) ? 1.0F : 0.0F;
+            store_vector4(inst, machine, result);
+            if (DEBUG_PROG) {
+               printf("SGT (%g %g %g %g) = (%g %g %g %g) > (%g %g %g %g)\n",
+                      result[0], result[1], result[2], result[3],
+                      a[0], a[1], a[2], a[3],
+                      b[0], b[1], b[2], b[3]);
+            }
+         }
+         break;
+      case OPCODE_SIN:
+         {
+            GLfloat a[4], result[4];
+            fetch_vector1(&inst->SrcReg[0], machine, a);
+            result[0] = result[1] = result[2] = result[3]
+               = (GLfloat) sin(a[0]);
+            store_vector4(inst, machine, result);
+         }
+         break;
+      case OPCODE_SLE:         /* set on less or equal */
+         {
+            GLfloat a[4], b[4], result[4];
+            fetch_vector4(&inst->SrcReg[0], machine, a);
+            fetch_vector4(&inst->SrcReg[1], machine, b);
+            result[0] = (a[0] <= b[0]) ? 1.0F : 0.0F;
+            result[1] = (a[1] <= b[1]) ? 1.0F : 0.0F;
+            result[2] = (a[2] <= b[2]) ? 1.0F : 0.0F;
+            result[3] = (a[3] <= b[3]) ? 1.0F : 0.0F;
+            store_vector4(inst, machine, result);
+            if (DEBUG_PROG) {
+               printf("SLE (%g %g %g %g) = (%g %g %g %g) <= (%g %g %g %g)\n",
+                      result[0], result[1], result[2], result[3],
+                      a[0], a[1], a[2], a[3],
+                      b[0], b[1], b[2], b[3]);
+            }
+         }
+         break;
+      case OPCODE_SLT:         /* set on less */
+         {
+            GLfloat a[4], b[4], result[4];
+            fetch_vector4(&inst->SrcReg[0], machine, a);
+            fetch_vector4(&inst->SrcReg[1], machine, b);
+            result[0] = (a[0] < b[0]) ? 1.0F : 0.0F;
+            result[1] = (a[1] < b[1]) ? 1.0F : 0.0F;
+            result[2] = (a[2] < b[2]) ? 1.0F : 0.0F;
+            result[3] = (a[3] < b[3]) ? 1.0F : 0.0F;
+            store_vector4(inst, machine, result);
+            if (DEBUG_PROG) {
+               printf("SLT (%g %g %g %g) = (%g %g %g %g) < (%g %g %g %g)\n",
+                      result[0], result[1], result[2], result[3],
+                      a[0], a[1], a[2], a[3],
+                      b[0], b[1], b[2], b[3]);
+            }
+         }
+         break;
+      case OPCODE_SNE:         /* set on not equal */
+         {
+            GLfloat a[4], b[4], result[4];
+            fetch_vector4(&inst->SrcReg[0], machine, a);
+            fetch_vector4(&inst->SrcReg[1], machine, b);
+            result[0] = (a[0] != b[0]) ? 1.0F : 0.0F;
+            result[1] = (a[1] != b[1]) ? 1.0F : 0.0F;
+            result[2] = (a[2] != b[2]) ? 1.0F : 0.0F;
+            result[3] = (a[3] != b[3]) ? 1.0F : 0.0F;
+            store_vector4(inst, machine, result);
+            if (DEBUG_PROG) {
+               printf("SNE (%g %g %g %g) = (%g %g %g %g) != (%g %g %g %g)\n",
+                      result[0], result[1], result[2], result[3],
+                      a[0], a[1], a[2], a[3],
+                      b[0], b[1], b[2], b[3]);
+            }
+         }
+         break;
+      case OPCODE_SSG:         /* set sign (-1, 0 or +1) */
+         {
+            GLfloat a[4], result[4];
+            fetch_vector4(&inst->SrcReg[0], machine, a);
+            result[0] = (GLfloat) ((a[0] > 0.0F) - (a[0] < 0.0F));
+            result[1] = (GLfloat) ((a[1] > 0.0F) - (a[1] < 0.0F));
+            result[2] = (GLfloat) ((a[2] > 0.0F) - (a[2] < 0.0F));
+            result[3] = (GLfloat) ((a[3] > 0.0F) - (a[3] < 0.0F));
+            store_vector4(inst, machine, result);
+         }
+         break;
+      case OPCODE_STR:         /* set true, operands ignored */
+         {
+            static const GLfloat result[4] = { 1.0F, 1.0F, 1.0F, 1.0F };
+            store_vector4(inst, machine, result);
+         }
+         break;
+      case OPCODE_SUB:
+         {
+            GLfloat a[4], b[4], result[4];
+            fetch_vector4(&inst->SrcReg[0], machine, a);
+            fetch_vector4(&inst->SrcReg[1], machine, b);
+            result[0] = a[0] - b[0];
+            result[1] = a[1] - b[1];
+            result[2] = a[2] - b[2];
+            result[3] = a[3] - b[3];
+            store_vector4(inst, machine, result);
+            if (DEBUG_PROG) {
+               printf("SUB (%g %g %g %g) = (%g %g %g %g) - (%g %g %g %g)\n",
+                      result[0], result[1], result[2], result[3],
+                      a[0], a[1], a[2], a[3], b[0], b[1], b[2], b[3]);
+            }
+         }
+         break;
+      case OPCODE_SWZ:         /* extended swizzle */
+         {
+            const struct prog_src_register *source = &inst->SrcReg[0];
+            const GLfloat *src = get_src_register_pointer(source, machine);
+            GLfloat result[4];
+            GLuint i;
+            for (i = 0; i < 4; i++) {
+               const GLuint swz = GET_SWZ(source->Swizzle, i);
+               if (swz == SWIZZLE_ZERO)
+                  result[i] = 0.0;
+               else if (swz == SWIZZLE_ONE)
+                  result[i] = 1.0;
+               else {
+                  ASSERT(swz >= 0);
+                  ASSERT(swz <= 3);
+                  result[i] = src[swz];
+               }
+               if (source->Negate & (1 << i))
+                  result[i] = -result[i];
+            }
+            store_vector4(inst, machine, result);
+         }
+         break;
+      case OPCODE_TEX:         /* Both ARB and NV frag prog */
+         /* Simple texel lookup */
+         {
+            GLfloat texcoord[4], color[4];
+            fetch_vector4(&inst->SrcReg[0], machine, texcoord);
+
+            fetch_texel(ctx, machine, inst, texcoord, 0.0, color);
+
+            if (DEBUG_PROG) {
+               printf("TEX (%g, %g, %g, %g) = texture[%d][%g, %g, %g, %g]\n",
+                      color[0], color[1], color[2], color[3],
+                      inst->TexSrcUnit,
+                      texcoord[0], texcoord[1], texcoord[2], texcoord[3]);
+            }
+            store_vector4(inst, machine, color);
+         }
+         break;
+      case OPCODE_TXB:         /* GL_ARB_fragment_program only */
+         /* Texel lookup with LOD bias */
+         {
+            GLfloat texcoord[4], color[4], lodBias;
+
+            fetch_vector4(&inst->SrcReg[0], machine, texcoord);
+
+            /* texcoord[3] is the bias to add to lambda */
+            lodBias = texcoord[3];
+
+            fetch_texel(ctx, machine, inst, texcoord, lodBias, color);
+
+            if (DEBUG_PROG) {
+               printf("TXB (%g, %g, %g, %g) = texture[%d][%g %g %g %g]"
+                      "  bias %g\n",
+                      color[0], color[1], color[2], color[3],
+                      inst->TexSrcUnit,
+                      texcoord[0],
+                      texcoord[1],
+                      texcoord[2],
+                      texcoord[3],
+                      lodBias);
+            }
+
+            store_vector4(inst, machine, color);
+         }
+         break;
+      case OPCODE_TXD:         /* GL_NV_fragment_program only */
+         /* Texture lookup w/ partial derivatives for LOD */
+         {
+            GLfloat texcoord[4], dtdx[4], dtdy[4], color[4];
+            fetch_vector4(&inst->SrcReg[0], machine, texcoord);
+            fetch_vector4(&inst->SrcReg[1], machine, dtdx);
+            fetch_vector4(&inst->SrcReg[2], machine, dtdy);
+            machine->FetchTexelDeriv(ctx, texcoord, dtdx, dtdy,
+                                     0.0, /* lodBias */
+                                     inst->TexSrcUnit, color);
+            store_vector4(inst, machine, color);
+         }
+         break;
+      case OPCODE_TXL:
+         /* Texel lookup with explicit LOD */
+         {
+            GLfloat texcoord[4], color[4], lod;
+
+            fetch_vector4(&inst->SrcReg[0], machine, texcoord);
+
+            /* texcoord[3] is the LOD */
+            lod = texcoord[3];
+
+	    machine->FetchTexelLod(ctx, texcoord, lod,
+				   machine->Samplers[inst->TexSrcUnit], color);
+
+            store_vector4(inst, machine, color);
+         }
+         break;
+      case OPCODE_TXP:         /* GL_ARB_fragment_program only */
+         /* Texture lookup w/ projective divide */
+         {
+            GLfloat texcoord[4], color[4];
+
+            fetch_vector4(&inst->SrcReg[0], machine, texcoord);
+            /* Not so sure about this test - if texcoord[3] is
+             * zero, we'd probably be fine except for an ASSERT in
+             * IROUND_POS() which gets triggered by the inf values created.
+             */
+            if (texcoord[3] != 0.0) {
+               texcoord[0] /= texcoord[3];
+               texcoord[1] /= texcoord[3];
+               texcoord[2] /= texcoord[3];
+            }
+
+            fetch_texel(ctx, machine, inst, texcoord, 0.0, color);
+
+            store_vector4(inst, machine, color);
+         }
+         break;
+      case OPCODE_TXP_NV:      /* GL_NV_fragment_program only */
+         /* Texture lookup w/ projective divide, as above, but do not
+          * do the divide by w if sampling from a cube map.
+          */
+         {
+            GLfloat texcoord[4], color[4];
+
+            fetch_vector4(&inst->SrcReg[0], machine, texcoord);
+            if (inst->TexSrcTarget != TEXTURE_CUBE_INDEX &&
+                texcoord[3] != 0.0) {
+               texcoord[0] /= texcoord[3];
+               texcoord[1] /= texcoord[3];
+               texcoord[2] /= texcoord[3];
+            }
+
+            fetch_texel(ctx, machine, inst, texcoord, 0.0, color);
+
+            store_vector4(inst, machine, color);
+         }
+         break;
+      case OPCODE_TRUNC:       /* truncate toward zero */
+         {
+            GLfloat a[4], result[4];
+            fetch_vector4(&inst->SrcReg[0], machine, a);
+            result[0] = (GLfloat) (GLint) a[0];
+            result[1] = (GLfloat) (GLint) a[1];
+            result[2] = (GLfloat) (GLint) a[2];
+            result[3] = (GLfloat) (GLint) a[3];
+            store_vector4(inst, machine, result);
+         }
+         break;
+      case OPCODE_UP2H:        /* unpack two 16-bit floats */
+         {
+            const GLuint raw = fetch_vector1ui(&inst->SrcReg[0], machine);
+            GLfloat result[4];
+            GLushort hx, hy;
+            hx = raw & 0xffff;
+            hy = raw >> 16;
+            result[0] = result[2] = _mesa_half_to_float(hx);
+            result[1] = result[3] = _mesa_half_to_float(hy);
+            store_vector4(inst, machine, result);
+         }
+         break;
+      case OPCODE_UP2US:       /* unpack two GLushorts */
+         {
+            const GLuint raw = fetch_vector1ui(&inst->SrcReg[0], machine);
+            GLfloat result[4];
+            GLushort usx, usy;
+            usx = raw & 0xffff;
+            usy = raw >> 16;
+            result[0] = result[2] = usx * (1.0f / 65535.0f);
+            result[1] = result[3] = usy * (1.0f / 65535.0f);
+            store_vector4(inst, machine, result);
+         }
+         break;
+      case OPCODE_UP4B:        /* unpack four GLbytes */
+         {
+            const GLuint raw = fetch_vector1ui(&inst->SrcReg[0], machine);
+            GLfloat result[4];
+            result[0] = (((raw >> 0) & 0xff) - 128) / 127.0F;
+            result[1] = (((raw >> 8) & 0xff) - 128) / 127.0F;
+            result[2] = (((raw >> 16) & 0xff) - 128) / 127.0F;
+            result[3] = (((raw >> 24) & 0xff) - 128) / 127.0F;
+            store_vector4(inst, machine, result);
+         }
+         break;
+      case OPCODE_UP4UB:       /* unpack four GLubytes */
+         {
+            const GLuint raw = fetch_vector1ui(&inst->SrcReg[0], machine);
+            GLfloat result[4];
+            result[0] = ((raw >> 0) & 0xff) / 255.0F;
+            result[1] = ((raw >> 8) & 0xff) / 255.0F;
+            result[2] = ((raw >> 16) & 0xff) / 255.0F;
+            result[3] = ((raw >> 24) & 0xff) / 255.0F;
+            store_vector4(inst, machine, result);
+         }
+         break;
+      case OPCODE_XOR:         /* bitwise XOR */
+         {
+            GLuint a[4], b[4], result[4];
+            fetch_vector4ui(&inst->SrcReg[0], machine, a);
+            fetch_vector4ui(&inst->SrcReg[1], machine, b);
+            result[0] = a[0] ^ b[0];
+            result[1] = a[1] ^ b[1];
+            result[2] = a[2] ^ b[2];
+            result[3] = a[3] ^ b[3];
+            store_vector4ui(inst, machine, result);
+         }
+         break;
+      case OPCODE_XPD:         /* cross product */
+         {
+            GLfloat a[4], b[4], result[4];
+            fetch_vector4(&inst->SrcReg[0], machine, a);
+            fetch_vector4(&inst->SrcReg[1], machine, b);
+            result[0] = a[1] * b[2] - a[2] * b[1];
+            result[1] = a[2] * b[0] - a[0] * b[2];
+            result[2] = a[0] * b[1] - a[1] * b[0];
+            result[3] = 1.0;
+            store_vector4(inst, machine, result);
+            if (DEBUG_PROG) {
+               printf("XPD (%g %g %g %g) = (%g %g %g) X (%g %g %g)\n",
+                      result[0], result[1], result[2], result[3],
+                      a[0], a[1], a[2], b[0], b[1], b[2]);
+            }
+         }
+         break;
+      case OPCODE_X2D:         /* 2-D matrix transform */
+         {
+            GLfloat a[4], b[4], c[4], result[4];
+            fetch_vector4(&inst->SrcReg[0], machine, a);
+            fetch_vector4(&inst->SrcReg[1], machine, b);
+            fetch_vector4(&inst->SrcReg[2], machine, c);
+            result[0] = a[0] + b[0] * c[0] + b[1] * c[1];
+            result[1] = a[1] + b[0] * c[2] + b[1] * c[3];
+            result[2] = a[2] + b[0] * c[0] + b[1] * c[1];
+            result[3] = a[3] + b[0] * c[2] + b[1] * c[3];
+            store_vector4(inst, machine, result);
+         }
+         break;
+      case OPCODE_PRINT:
+         {
+            if (inst->SrcReg[0].File != PROGRAM_UNDEFINED) {
+               GLfloat a[4];
+               fetch_vector4(&inst->SrcReg[0], machine, a);
+               printf("%s%g, %g, %g, %g\n", (const char *) inst->Data,
+                            a[0], a[1], a[2], a[3]);
+            }
+            else {
+               printf("%s\n", (const char *) inst->Data);
+            }
+         }
+         break;
+      case OPCODE_END:
+         return GL_TRUE;
+      default:
+         _mesa_problem(ctx, "Bad opcode %d in _mesa_execute_program",
+                       inst->Opcode);
+         return GL_TRUE;        /* return value doesn't matter */
+      }
+
+      numExec++;
+      if (numExec > maxExec) {
+	 static GLboolean reported = GL_FALSE;
+	 if (!reported) {
+	    _mesa_problem(ctx, "Infinite loop detected in fragment program");
+	    reported = GL_TRUE;
+	 }
+         return GL_TRUE;
+      }
+
+   } /* for pc */
+
+   return GL_TRUE;
+}