1//
2// Copyright 2019 Karol Herbst
3//
4// Permission is hereby granted, free of charge, to any person obtaining a
5// copy of this software and associated documentation files (the "Software"),
6// to deal in the Software without restriction, including without limitation
7// the rights to use, copy, modify, merge, publish, distribute, sublicense,
8// and/or sell copies of the Software, and to permit persons to whom the
9// Software is furnished to do so, subject to the following conditions:
10//
11// The above copyright notice and this permission notice shall be included in
12// all copies or substantial portions of the Software.
13//
14// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
17// THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
18// OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
19// ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
20// OTHER DEALINGS IN THE SOFTWARE.
21//
22
23#include "invocation.hpp"
24
25#include <tuple>
26
27#include "core/device.hpp"
28#include "core/error.hpp"
29#include "core/binary.hpp"
30#include "pipe/p_state.h"
31#include "util/algorithm.hpp"
32#include "util/functional.hpp"
33
34#include <compiler/glsl_types.h>
35#include <compiler/nir/nir_builder.h>
36#include <compiler/nir/nir_serialize.h>
37#include <compiler/spirv/nir_spirv.h>
38#include <util/u_math.h>
39
40using namespace clover;
41
42#ifdef HAVE_CLOVER_SPIRV
43
44// Refs and unrefs the glsl_type_singleton.
45static class glsl_type_ref {
46public:
47   glsl_type_ref() {
48      glsl_type_singleton_init_or_ref();
49   }
50
51   ~glsl_type_ref() {
52      glsl_type_singleton_decref();
53   }
54} glsl_type_ref;
55
56static const nir_shader_compiler_options *
57dev_get_nir_compiler_options(const device &dev)
58{
59   const void *co = dev.get_compiler_options(PIPE_SHADER_IR_NIR);
60   return static_cast<const nir_shader_compiler_options*>(co);
61}
62
63static void debug_function(void *private_data,
64                   enum nir_spirv_debug_level level, size_t spirv_offset,
65                   const char *message)
66{
67   assert(private_data);
68   auto r_log = reinterpret_cast<std::string *>(private_data);
69   *r_log += message;
70}
71
72static void
73clover_arg_size_align(const glsl_type *type, unsigned *size, unsigned *align)
74{
75   if (type == glsl_type::sampler_type) {
76      *size = 0;
77      *align = 1;
78   } else if (type->is_image()) {
79      *size = *align = sizeof(cl_mem);
80   } else {
81      *size = type->cl_size();
82      *align = type->cl_alignment();
83   }
84}
85
86static bool
87clover_nir_lower_images(nir_shader *shader)
88{
89   nir_function_impl *impl = nir_shader_get_entrypoint(shader);
90
91   ASSERTED int last_loc = -1;
92   int num_rd_images = 0, num_wr_images = 0, num_samplers = 0;
93   nir_foreach_uniform_variable(var, shader) {
94      if (glsl_type_is_image(var->type) || glsl_type_is_sampler(var->type)) {
95         /* Assume they come in order */
96         assert(var->data.location > last_loc);
97         last_loc = var->data.location;
98      }
99
100      /* TODO: Constant samplers */
101      if (var->type == glsl_bare_sampler_type()) {
102         var->data.driver_location = num_samplers++;
103      } else if (glsl_type_is_image(var->type)) {
104         if (var->data.access & ACCESS_NON_WRITEABLE)
105            var->data.driver_location = num_rd_images++;
106         else
107            var->data.driver_location = num_wr_images++;
108      } else {
109         /* CL shouldn't have any sampled images */
110         assert(!glsl_type_is_sampler(var->type));
111      }
112   }
113   shader->info.num_textures = num_rd_images;
114   BITSET_ZERO(shader->info.textures_used);
115   if (num_rd_images)
116      BITSET_SET_RANGE_INSIDE_WORD(shader->info.textures_used, 0, num_rd_images - 1);
117   shader->info.num_images = num_wr_images;
118
119   nir_builder b;
120   nir_builder_init(&b, impl);
121
122   bool progress = false;
123   nir_foreach_block_reverse(block, impl) {
124      nir_foreach_instr_reverse_safe(instr, block) {
125         switch (instr->type) {
126         case nir_instr_type_deref: {
127            nir_deref_instr *deref = nir_instr_as_deref(instr);
128            if (deref->deref_type != nir_deref_type_var)
129               break;
130
131            if (!glsl_type_is_image(deref->type) &&
132                !glsl_type_is_sampler(deref->type))
133               break;
134
135            b.cursor = nir_instr_remove(&deref->instr);
136            nir_ssa_def *loc =
137               nir_imm_intN_t(&b, deref->var->data.driver_location,
138                                  deref->dest.ssa.bit_size);
139            nir_ssa_def_rewrite_uses(&deref->dest.ssa, loc);
140            progress = true;
141            break;
142         }
143
144         case nir_instr_type_tex: {
145            nir_tex_instr *tex = nir_instr_as_tex(instr);
146            unsigned count = 0;
147            for (unsigned i = 0; i < tex->num_srcs; i++) {
148               if (tex->src[i].src_type == nir_tex_src_texture_deref ||
149                   tex->src[i].src_type == nir_tex_src_sampler_deref) {
150                  nir_deref_instr *deref = nir_src_as_deref(tex->src[i].src);
151                  if (deref->deref_type == nir_deref_type_var) {
152                     /* In this case, we know the actual variable */
153                     if (tex->src[i].src_type == nir_tex_src_texture_deref)
154                        tex->texture_index = deref->var->data.driver_location;
155                     else
156                        tex->sampler_index = deref->var->data.driver_location;
157                     /* This source gets discarded */
158                     nir_instr_rewrite_src(&tex->instr, &tex->src[i].src,
159                                           NIR_SRC_INIT);
160                     continue;
161                  } else {
162                     assert(tex->src[i].src.is_ssa);
163                     b.cursor = nir_before_instr(&tex->instr);
164                     /* Back-ends expect a 32-bit thing, not 64-bit */
165                     nir_ssa_def *offset = nir_u2u32(&b, tex->src[i].src.ssa);
166                     if (tex->src[i].src_type == nir_tex_src_texture_deref)
167                        tex->src[count].src_type = nir_tex_src_texture_offset;
168                     else
169                        tex->src[count].src_type = nir_tex_src_sampler_offset;
170                     nir_instr_rewrite_src(&tex->instr, &tex->src[count].src,
171                                           nir_src_for_ssa(offset));
172                  }
173               } else {
174                  /* If we've removed a source, move this one down */
175                  if (count != i) {
176                     assert(count < i);
177                     tex->src[count].src_type = tex->src[i].src_type;
178                     nir_instr_move_src(&tex->instr, &tex->src[count].src,
179                                        &tex->src[i].src);
180                  }
181               }
182               count++;
183            }
184            tex->num_srcs = count;
185            progress = true;
186            break;
187         }
188
189         case nir_instr_type_intrinsic: {
190            nir_intrinsic_instr *intrin = nir_instr_as_intrinsic(instr);
191            switch (intrin->intrinsic) {
192            case nir_intrinsic_image_deref_load:
193            case nir_intrinsic_image_deref_store:
194            case nir_intrinsic_image_deref_atomic_add:
195            case nir_intrinsic_image_deref_atomic_imin:
196            case nir_intrinsic_image_deref_atomic_umin:
197            case nir_intrinsic_image_deref_atomic_imax:
198            case nir_intrinsic_image_deref_atomic_umax:
199            case nir_intrinsic_image_deref_atomic_and:
200            case nir_intrinsic_image_deref_atomic_or:
201            case nir_intrinsic_image_deref_atomic_xor:
202            case nir_intrinsic_image_deref_atomic_exchange:
203            case nir_intrinsic_image_deref_atomic_comp_swap:
204            case nir_intrinsic_image_deref_atomic_fadd:
205            case nir_intrinsic_image_deref_atomic_inc_wrap:
206            case nir_intrinsic_image_deref_atomic_dec_wrap:
207            case nir_intrinsic_image_deref_size:
208            case nir_intrinsic_image_deref_samples: {
209               assert(intrin->src[0].is_ssa);
210               b.cursor = nir_before_instr(&intrin->instr);
211               /* Back-ends expect a 32-bit thing, not 64-bit */
212               nir_ssa_def *offset = nir_u2u32(&b, intrin->src[0].ssa);
213               nir_rewrite_image_intrinsic(intrin, offset, false);
214               progress = true;
215               break;
216            }
217
218            default:
219               break;
220            }
221            break;
222         }
223
224         default:
225            break;
226         }
227      }
228   }
229
230   if (progress) {
231      nir_metadata_preserve(impl, nir_metadata_block_index |
232                                  nir_metadata_dominance);
233   } else {
234      nir_metadata_preserve(impl, nir_metadata_all);
235   }
236
237   return progress;
238}
239
240struct clover_lower_nir_state {
241   std::vector<binary::argument> &args;
242   uint32_t global_dims;
243   nir_variable *constant_var;
244   nir_variable *printf_buffer;
245   nir_variable *offset_vars[3];
246};
247
248static bool
249clover_lower_nir_filter(const nir_instr *instr, const void *)
250{
251   return instr->type == nir_instr_type_intrinsic;
252}
253
254static nir_ssa_def *
255clover_lower_nir_instr(nir_builder *b, nir_instr *instr, void *_state)
256{
257   clover_lower_nir_state *state = reinterpret_cast<clover_lower_nir_state*>(_state);
258   nir_intrinsic_instr *intrinsic = nir_instr_as_intrinsic(instr);
259
260   switch (intrinsic->intrinsic) {
261   case nir_intrinsic_load_printf_buffer_address: {
262      if (!state->printf_buffer) {
263         unsigned location = state->args.size();
264         state->args.emplace_back(binary::argument::global, sizeof(size_t),
265                                  8, 8, binary::argument::zero_ext,
266                                  binary::argument::printf_buffer);
267
268         const glsl_type *type = glsl_uint64_t_type();
269         state->printf_buffer = nir_variable_create(b->shader, nir_var_uniform,
270                                                    type, "global_printf_buffer");
271         state->printf_buffer->data.location = location;
272      }
273      return nir_load_var(b, state->printf_buffer);
274   }
275   case nir_intrinsic_load_base_global_invocation_id: {
276      nir_ssa_def *loads[3];
277
278      /* create variables if we didn't do so alrady */
279      if (!state->offset_vars[0]) {
280         /* TODO: fix for 64 bit */
281         /* Even though we only place one scalar argument, clover will bind up to
282          * three 32 bit values
283         */
284         unsigned location = state->args.size();
285         state->args.emplace_back(binary::argument::scalar, 4, 4, 4,
286                                  binary::argument::zero_ext,
287                                  binary::argument::grid_offset);
288
289         const glsl_type *type = glsl_uint_type();
290         for (uint32_t i = 0; i < 3; i++) {
291            state->offset_vars[i] =
292               nir_variable_create(b->shader, nir_var_uniform, type,
293                                   "global_invocation_id_offsets");
294            state->offset_vars[i]->data.location = location + i;
295         }
296      }
297
298      for (int i = 0; i < 3; i++) {
299         nir_variable *var = state->offset_vars[i];
300         loads[i] = var ? nir_load_var(b, var) : nir_imm_int(b, 0);
301      }
302
303      return nir_u2u(b, nir_vec(b, loads, state->global_dims),
304                     nir_dest_bit_size(intrinsic->dest));
305   }
306   case nir_intrinsic_load_constant_base_ptr: {
307      return nir_load_var(b, state->constant_var);
308   }
309
310   default:
311      return NULL;
312   }
313}
314
315static bool
316clover_lower_nir(nir_shader *nir, std::vector<binary::argument> &args,
317                 uint32_t dims, uint32_t pointer_bit_size)
318{
319   nir_variable *constant_var = NULL;
320   if (nir->constant_data_size) {
321      const glsl_type *type = pointer_bit_size == 64 ? glsl_uint64_t_type() : glsl_uint_type();
322
323      constant_var = nir_variable_create(nir, nir_var_uniform, type,
324                                         "constant_buffer_addr");
325      constant_var->data.location = args.size();
326
327      args.emplace_back(binary::argument::global, sizeof(cl_mem),
328                        pointer_bit_size / 8, pointer_bit_size / 8,
329                        binary::argument::zero_ext,
330                        binary::argument::constant_buffer);
331   }
332
333   clover_lower_nir_state state = { args, dims, constant_var };
334   return nir_shader_lower_instructions(nir,
335      clover_lower_nir_filter, clover_lower_nir_instr, &state);
336}
337
338static spirv_to_nir_options
339create_spirv_options(const device &dev, std::string &r_log)
340{
341   struct spirv_to_nir_options spirv_options = {};
342   spirv_options.environment = NIR_SPIRV_OPENCL;
343   if (dev.address_bits() == 32u) {
344      spirv_options.shared_addr_format = nir_address_format_32bit_offset;
345      spirv_options.global_addr_format = nir_address_format_32bit_global;
346      spirv_options.temp_addr_format = nir_address_format_32bit_offset;
347      spirv_options.constant_addr_format = nir_address_format_32bit_global;
348   } else {
349      spirv_options.shared_addr_format = nir_address_format_32bit_offset_as_64bit;
350      spirv_options.global_addr_format = nir_address_format_64bit_global;
351      spirv_options.temp_addr_format = nir_address_format_32bit_offset_as_64bit;
352      spirv_options.constant_addr_format = nir_address_format_64bit_global;
353   }
354   spirv_options.caps.address = true;
355   spirv_options.caps.float64 = true;
356   spirv_options.caps.int8 = true;
357   spirv_options.caps.int16 = true;
358   spirv_options.caps.int64 = true;
359   spirv_options.caps.kernel = true;
360   spirv_options.caps.kernel_image = dev.image_support();
361   spirv_options.caps.int64_atomics = dev.has_int64_atomics();
362   spirv_options.debug.func = &debug_function;
363   spirv_options.debug.private_data = &r_log;
364   spirv_options.caps.printf = true;
365   return spirv_options;
366}
367
368struct disk_cache *clover::nir::create_clc_disk_cache(void)
369{
370   struct mesa_sha1 ctx;
371   unsigned char sha1[20];
372   char cache_id[20 * 2 + 1];
373   _mesa_sha1_init(&ctx);
374
375   if (!disk_cache_get_function_identifier((void *)clover::nir::create_clc_disk_cache, &ctx))
376      return NULL;
377
378   _mesa_sha1_final(&ctx, sha1);
379
380   disk_cache_format_hex_id(cache_id, sha1, 20 * 2);
381   return disk_cache_create("clover-clc", cache_id, 0);
382}
383
384void clover::nir::check_for_libclc(const device &dev)
385{
386   if (!nir_can_find_libclc(dev.address_bits()))
387      throw error(CL_COMPILER_NOT_AVAILABLE);
388}
389
390nir_shader *clover::nir::load_libclc_nir(const device &dev, std::string &r_log)
391{
392   spirv_to_nir_options spirv_options = create_spirv_options(dev, r_log);
393   auto *compiler_options = dev_get_nir_compiler_options(dev);
394
395   return nir_load_libclc_shader(dev.address_bits(), dev.clc_cache,
396				 &spirv_options, compiler_options);
397}
398
399static bool
400can_remove_var(nir_variable *var, void *data)
401{
402   return !(var->type->is_sampler() || var->type->is_image());
403}
404
405binary clover::nir::spirv_to_nir(const binary &mod, const device &dev,
406                                 std::string &r_log)
407{
408   spirv_to_nir_options spirv_options = create_spirv_options(dev, r_log);
409   std::shared_ptr<nir_shader> nir = dev.clc_nir;
410   spirv_options.clc_shader = nir.get();
411
412   binary b;
413   // We only insert one section.
414   assert(mod.secs.size() == 1);
415   auto &section = mod.secs[0];
416
417   binary::resource_id section_id = 0;
418   for (const auto &sym : mod.syms) {
419      assert(sym.section == 0);
420
421      const auto *binary =
422         reinterpret_cast<const pipe_binary_program_header *>(section.data.data());
423      const uint32_t *data = reinterpret_cast<const uint32_t *>(binary->blob);
424      const size_t num_words = binary->num_bytes / 4;
425      const char *name = sym.name.c_str();
426      auto *compiler_options = dev_get_nir_compiler_options(dev);
427
428      nir_shader *nir = spirv_to_nir(data, num_words, nullptr, 0,
429                                     MESA_SHADER_KERNEL, name,
430                                     &spirv_options, compiler_options);
431      if (!nir) {
432         r_log += "Translation from SPIR-V to NIR for kernel \"" + sym.name +
433                  "\" failed.\n";
434         throw build_error();
435      }
436
437      nir->info.workgroup_size_variable = sym.reqd_work_group_size[0] == 0;
438      nir->info.workgroup_size[0] = sym.reqd_work_group_size[0];
439      nir->info.workgroup_size[1] = sym.reqd_work_group_size[1];
440      nir->info.workgroup_size[2] = sym.reqd_work_group_size[2];
441      nir_validate_shader(nir, "clover");
442
443      // Inline all functions first.
444      // according to the comment on nir_inline_functions
445      NIR_PASS_V(nir, nir_lower_variable_initializers, nir_var_function_temp);
446      NIR_PASS_V(nir, nir_lower_returns);
447      NIR_PASS_V(nir, nir_lower_libclc, spirv_options.clc_shader);
448
449      NIR_PASS_V(nir, nir_inline_functions);
450      NIR_PASS_V(nir, nir_copy_prop);
451      NIR_PASS_V(nir, nir_opt_deref);
452
453      // Pick off the single entrypoint that we want.
454      foreach_list_typed_safe(nir_function, func, node, &nir->functions) {
455         if (!func->is_entrypoint)
456            exec_node_remove(&func->node);
457      }
458      assert(exec_list_length(&nir->functions) == 1);
459
460      nir_validate_shader(nir, "clover after function inlining");
461
462      NIR_PASS_V(nir, nir_lower_variable_initializers, ~nir_var_function_temp);
463
464      struct nir_lower_printf_options printf_options;
465      printf_options.treat_doubles_as_floats = false;
466      printf_options.max_buffer_size = dev.max_printf_buffer_size();
467
468      NIR_PASS_V(nir, nir_lower_printf, &printf_options);
469
470      NIR_PASS_V(nir, nir_remove_dead_variables, nir_var_function_temp, NULL);
471
472      // copy propagate to prepare for lower_explicit_io
473      NIR_PASS_V(nir, nir_split_var_copies);
474      NIR_PASS_V(nir, nir_opt_copy_prop_vars);
475      NIR_PASS_V(nir, nir_lower_var_copies);
476      NIR_PASS_V(nir, nir_lower_vars_to_ssa);
477      NIR_PASS_V(nir, nir_opt_dce);
478      NIR_PASS_V(nir, nir_lower_convert_alu_types, NULL);
479
480      NIR_PASS_V(nir, nir_lower_system_values);
481      nir_lower_compute_system_values_options sysval_options = { 0 };
482      sysval_options.has_base_global_invocation_id = true;
483      NIR_PASS_V(nir, nir_lower_compute_system_values, &sysval_options);
484
485      // constant fold before lowering mem constants
486      NIR_PASS_V(nir, nir_opt_constant_folding);
487
488      NIR_PASS_V(nir, nir_remove_dead_variables, nir_var_mem_constant, NULL);
489      NIR_PASS_V(nir, nir_lower_vars_to_explicit_types, nir_var_mem_constant,
490                 glsl_get_cl_type_size_align);
491      if (nir->constant_data_size > 0) {
492         assert(nir->constant_data == NULL);
493         nir->constant_data = rzalloc_size(nir, nir->constant_data_size);
494         nir_gather_explicit_io_initializers(nir, nir->constant_data,
495                                             nir->constant_data_size,
496                                             nir_var_mem_constant);
497      }
498      NIR_PASS_V(nir, nir_lower_explicit_io, nir_var_mem_constant,
499                 spirv_options.constant_addr_format);
500
501      auto args = sym.args;
502      NIR_PASS_V(nir, clover_lower_nir, args, dev.max_block_size().size(),
503                 dev.address_bits());
504
505      NIR_PASS_V(nir, nir_lower_vars_to_explicit_types,
506                 nir_var_uniform, clover_arg_size_align);
507      NIR_PASS_V(nir, nir_lower_vars_to_explicit_types,
508                 nir_var_mem_shared | nir_var_mem_global |
509                 nir_var_function_temp,
510                 glsl_get_cl_type_size_align);
511
512      NIR_PASS_V(nir, nir_opt_deref);
513      NIR_PASS_V(nir, nir_lower_readonly_images_to_tex, false);
514      NIR_PASS_V(nir, clover_nir_lower_images);
515      NIR_PASS_V(nir, nir_lower_memcpy);
516
517      /* use offsets for kernel inputs (uniform) */
518      NIR_PASS_V(nir, nir_lower_explicit_io, nir_var_uniform,
519                 nir->info.cs.ptr_size == 64 ?
520                 nir_address_format_32bit_offset_as_64bit :
521                 nir_address_format_32bit_offset);
522
523      NIR_PASS_V(nir, nir_lower_explicit_io, nir_var_mem_constant,
524                 spirv_options.constant_addr_format);
525      NIR_PASS_V(nir, nir_lower_explicit_io, nir_var_mem_shared,
526                 spirv_options.shared_addr_format);
527
528      NIR_PASS_V(nir, nir_lower_explicit_io, nir_var_function_temp,
529                 spirv_options.temp_addr_format);
530
531      NIR_PASS_V(nir, nir_lower_explicit_io, nir_var_mem_global,
532                 spirv_options.global_addr_format);
533
534      struct nir_remove_dead_variables_options remove_dead_variables_options = {
535            .can_remove_var = can_remove_var,
536      };
537      NIR_PASS_V(nir, nir_remove_dead_variables, nir_var_all, &remove_dead_variables_options);
538
539      if (compiler_options->lower_int64_options)
540         NIR_PASS_V(nir, nir_lower_int64);
541
542      NIR_PASS_V(nir, nir_opt_dce);
543
544      if (nir->constant_data_size) {
545         const char *ptr = reinterpret_cast<const char *>(nir->constant_data);
546         const binary::section constants {
547            section_id,
548            binary::section::data_constant,
549            nir->constant_data_size,
550            { ptr, ptr + nir->constant_data_size }
551         };
552         nir->constant_data = NULL;
553         nir->constant_data_size = 0;
554         b.secs.push_back(constants);
555      }
556
557      void *mem_ctx = ralloc_context(NULL);
558      unsigned printf_info_count = nir->printf_info_count;
559      nir_printf_info *printf_infos = nir->printf_info;
560
561      ralloc_steal(mem_ctx, printf_infos);
562
563      struct blob blob;
564      blob_init(&blob);
565      nir_serialize(&blob, nir, false);
566
567      ralloc_free(nir);
568
569      const pipe_binary_program_header header { uint32_t(blob.size) };
570      binary::section text { section_id, binary::section::text_executable, header.num_bytes, {} };
571      text.data.insert(text.data.end(), reinterpret_cast<const char *>(&header),
572                       reinterpret_cast<const char *>(&header) + sizeof(header));
573      text.data.insert(text.data.end(), blob.data, blob.data + blob.size);
574
575      free(blob.data);
576
577      b.printf_strings_in_buffer = false;
578      b.printf_infos.reserve(printf_info_count);
579      for (unsigned i = 0; i < printf_info_count; i++) {
580         binary::printf_info info;
581
582         info.arg_sizes.reserve(printf_infos[i].num_args);
583         for (unsigned j = 0; j < printf_infos[i].num_args; j++)
584            info.arg_sizes.push_back(printf_infos[i].arg_sizes[j]);
585
586         info.strings.resize(printf_infos[i].string_size);
587         memcpy(info.strings.data(), printf_infos[i].strings, printf_infos[i].string_size);
588         b.printf_infos.push_back(info);
589      }
590
591      ralloc_free(mem_ctx);
592
593      b.syms.emplace_back(sym.name, sym.attributes,
594                          sym.reqd_work_group_size, section_id, 0, args);
595      b.secs.push_back(text);
596      section_id++;
597   }
598   return b;
599}
600#else
601binary clover::nir::spirv_to_nir(const binary &mod, const device &dev, std::string &r_log)
602{
603   r_log += "SPIR-V support in clover is not enabled.\n";
604   throw error(CL_LINKER_NOT_AVAILABLE);
605}
606#endif
607