[Polly] [PPCG] [2/3] Collect all changes to `lib/External/*` due to PPCG update.

[bollu]

Summary

• Has polly-speific changes to PPCG. Polly exports certain functionality that is private to PPCG. It also creates stubs for large parts of the pet API as well as other functions in ppcg/external.c to keep the linker happy.

• This commit includes changes to CMakeLists.txt.

[grosser]

lib/External/pet/include/pet.h

315 ↗

(On Diff #107483)

These changes belong to 1!

lib/External/ppcg/GIT_HEAD_ID

1 ↗

(On Diff #107483)

Previous commit!

lib/External/ppcg/cuda.c

23

???

lib/External/ppcg/external.c

50

Remove?

lib/External/ppcg/gpu.c

2477

Alignment

[bollu]

• diff with stuff moved to [1/3].

[bollu]

• Update again because SHA hashes changed, leading to an incorrect diff previously.

[bollu]

• Change spaces to tabs, looks like PPCG uses tabs.

[bollu]

• Remove commented code.

[bollu]

closed by r308624

lib/External/CMakeLists.txt

elseif ()
   set(PPCG_GIT_HEAD_ID "UNKNOWN")
 endif ()
 
 message(STATUS "PPCG version: ${PPCG_GIT_HEAD_ID}")
 
 set (PPCG_FILES
      ppcg/cuda.c
      ppcg/cuda_common.c
+     ppcg/external.c
      ppcg/gpu_array_tile.c
      ppcg/gpu.c
+     ppcg/gpu_array_tile.c
      ppcg/gpu_group.c
+     ppcg/gpu_hybrid.c
      ppcg/gpu_print.c
      ppcg/gpu_tree.c
+     ppcg/grouping.c
+     ppcg/hybrid.c
      ppcg/ppcg.c
      ppcg/ppcg_options.c
+     ppcg/print.c
      ppcg/schedule.c
-     ppcg/external.c
+     ppcg/util.c
      )
 
 include_directories(BEFORE
   ${PPCG_BINARY_DIR}
   ${PPCG_SOURCE_DIR}/imath
   ${PPCG_SOURCE_DIR}/include
   ${PET_SOURCE_DIR}/include
 )

lib/External/ppcg/cuda.h

 #ifndef _CUDA_H
 #define _CUDA_H
 
 #include "ppcg_options.h"
 #include "ppcg.h"
 
 int generate_cuda(isl_ctx *ctx, struct ppcg_options *options,
   const char *input);
 
+__isl_give isl_printer *print_host_user(__isl_take isl_printer *p,
+  __isl_take isl_ast_print_options *print_options,
+  __isl_keep isl_ast_node *node, void *user);
 #endif

lib/External/ppcg/cuda.c

 #include "gpu.h"
 #include "gpu_print.h"
 #include "print.h"
 #include "util.h"
 
 static __isl_give isl_printer *print_cuda_macros(__isl_take isl_printer *p)
 {
   const char *macros =
     "#define cudaCheckReturn(ret) \\\n"
     "  do { \\\n"
     "    cudaError_t cudaCheckReturn_e = (ret); \\\n"
     "    if (cudaCheckReturn_e != cudaSuccess) { \\\n"
     "      fprintf(stderr, \"CUDA error: %s\\n\", "
     "cudaGetErrorString(cudaCheckReturn_e)); \\\n"
     "      fflush(stderr); \\\n"
     "    } \\\n"
     "    assert(cudaCheckReturn_e == cudaSuccess); \\\n"
static __isl_give isl_printer *copy_array_from_device(
   p = isl_printer_print_str(p, ", ");
   p = gpu_array_info_print_size(p, array);
   p = isl_printer_print_str(p, ", cudaMemcpyDeviceToHost));");
   p = isl_printer_end_line(p);
 
   return p;
 }
 
-static void print_reverse_list(FILE *out, int len, int *list)
+static __isl_give isl_printer* print_reverse_list(__isl_take isl_printer *p, int len, int *list)
 {
   int i;
 
-  if (!out || len == 0)
-    return;
+  if (len == 0)
+    return p;
 
-  fprintf(out, "(");
+  p = isl_printer_print_str(p, "(");
   for (i = 0; i < len; ++i) {
     if (i)
-      fprintf(out, ", ");
-    fprintf(out, "%d", list[len - 1 - i]);
+      p = isl_printer_print_str(p, ", ");
+    p = isl_printer_print_int(p, list[len - 1 - i]);
   }
-  fprintf(out, ")");
+  return isl_printer_print_str(p, ")");
 }
 
 /* Print the effective grid size as a list of the sizes in each
  * dimension, from innermost to outermost.
  */
 static __isl_give isl_printer *print_grid_size(__isl_take isl_printer *p,
   struct ppcg_kernel *kernel)
 {
static void print_kernel(struct gpu_prog *prog, struct ppcg_kernel *kernel,
 
   p = print_kernel_vars(p, kernel);
   p = isl_printer_end_line(p);
   p = ppcg_set_macro_names(p);
   p = gpu_print_macros(p, kernel->tree);
 
   print_options = isl_ast_print_options_alloc(ctx);
   print_options = isl_ast_print_options_set_print_user(print_options,
-                &print_kernel_stmt, NULL);
+              &print_kernel_stmt, NULL);
   p = isl_ast_node_print(kernel->tree, p, print_options);
   isl_printer_free(p);
 
   fprintf(cuda->kernel_c, "}\n");
 }
 
 /* Print code for initializing the device for execution of the transformed
  * code.  This includes declaring locally defined variables as well as

  * The original user statements and the kernel launches have
  * an associated annotation, while the other statements do not.
  * The latter are handled by print_device_node.
  * The annotation on the user statements is called "user".
  *
  * In case of a kernel launch, print a block of statements that
  * defines the grid and the block and then launches the kernel.
  */
-static __isl_give isl_printer *print_host_user(__isl_take isl_printer *p,
+__isl_give isl_printer *print_host_user(__isl_take isl_printer *p,
   __isl_take isl_ast_print_options *print_options,
   __isl_keep isl_ast_node *node, void *user)
 {
   isl_id *id;
   int is_user;
   struct ppcg_kernel *kernel;
   struct ppcg_kernel_stmt *stmt;
   struct print_host_user_data *data;
if (is_user)
     return ppcg_kernel_print_domain(p, stmt);
 
   p = ppcg_start_block(p);
 
   p = isl_printer_start_line(p);
   p = isl_printer_print_str(p, "dim3 k");
   p = isl_printer_print_int(p, kernel->id);
   p = isl_printer_print_str(p, "_dimBlock");
-  print_reverse_list(isl_printer_get_file(p),
-        kernel->n_block, kernel->block_dim);
+  p = print_reverse_list(p, kernel->n_block, kernel->block_dim);
   p = isl_printer_print_str(p, ";");
   p = isl_printer_end_line(p);
 
   p = print_grid(p, kernel);
 
   p = isl_printer_start_line(p);
   p = isl_printer_print_str(p, "kernel");
   p = isl_printer_print_int(p, kernel->id);
__isl_give isl_printer *print_host_user(__isl_take isl_printer *p,
   p = isl_printer_print_str(p, "cudaCheckKernel();");
   p = isl_printer_end_line(p);
 
   p = ppcg_end_block(p);
 
   p = isl_printer_start_line(p);
   p = isl_printer_end_line(p);
 
+#if 0
   print_kernel(data->prog, kernel, data->cuda);
+#endif
 
   return p;
 }
 
 static __isl_give isl_printer *print_host_code(__isl_take isl_printer *p,
   struct gpu_prog *prog, __isl_keep isl_ast_node *tree,
   struct cuda_info *cuda)
 {

lib/External/ppcg/external.c

 #include "assert.h"
 #include "stdio.h"
 #include "stdlib.h"
 
 #define die() { \
   fprintf(stderr, "Dummy function %s called\n", __FUNCTION__); \
   abort(); \
 }
 
-void ppcg_start_block() {
-  die();
-}
-void ppcg_end_block(){
-  die();
-}
-void ppcg_print_macros(){
-  die();
-}
 void pet_scop_compute_outer_to_any(){
   die();
 }
 void pet_scop_compute_outer_to_inner(){
   die();
 }
 void pet_tree_get_type(){
   die();
void pet_expr_access_get_index(){
   die();
 }
 void pet_expr_access_get_ref_id(){
   die();
 }
 void print_cpu(){
   die();
 }
-void ppcg_print_exposed_declarations(){
-  die();
-}
-void ppcg_print_declaration(){
-  die();
-}
+
 void pet_stmt_print_body(){
   die();
 }
 void pet_loc_get_start(){
   die();
 }
 void pet_loc_get_end(){
   die();
 }
void generate_opencl() {
   die();
 }
 void generate_cpu() {
   die();
 }
 void pet_stmt_build_ast_exprs() {
   die();
 }
+ void pet_scop_get_tagged_may_reads() {
+  die();
+}
+ void pet_scop_get_may_reads() {
+  die();
+}
+void pet_scop_get_may_writes() {
+  die();
+}
+void pet_scop_get_must_writes() {
+  die();
+}
+void pet_scop_get_tagged_may_writes() {
+  die();
+}
+void pet_scop_get_tagged_must_writes() {
+die();
+}
+void pet_scop_get_must_kills() {
+  die();
+}
+void pet_scop_get_tagged_must_kills() {
+  die();
+}
+void pet_expr_call_get_name() {
+  die();
+}
+void pet_expr_call_set_name() {
+  die();
+}
+void pet_expr_get_arg() {
+  die();
+}
+void pet_expr_new_cast() {
+  die();
+}
+void pet_expr_set_arg() {
+  die();
+}
+void pet_tree_copy() {
+  die();
+}
+void pet_tree_free() {
+  die();
+}
+void pet_tree_map_call_expr() {
+  die();
+}
+void pet_expr_access_get_may_read() {
+  die();
+}
+void pet_expr_access_get_may_write() {
+  die();
+}

lib/External/ppcg/gpu.h

struct gpu_array_info {
   /* Should the array be linearized? */
   int linearize;
 
   /* Order dependences on this array.
    * Only used if live_range_reordering option is set.
    * It is set to NULL otherwise.
    */
   isl_union_map *dep_order;
+
+    void *user;
 };
 
 /* Represents an outer array accessed by a ppcg_kernel, localized
  * to the context of this kernel.
  *
  * "array" points to the corresponding array in the gpu_prog.
  * The "n_group" "groups" are the reference groups associated to the array.
  * If "force_private" is set, then the array (in practice a scalar)
struct gpu_gen {
   struct ppcg_options *options;
 
   /* Callback for printing of AST in appropriate format. */
   __isl_give isl_printer *(*print)(__isl_take isl_printer *p,
     struct gpu_prog *prog, __isl_keep isl_ast_node *tree,
     struct gpu_types *types, void *user);
   void *print_user;
 
+    isl_id_to_ast_expr *(*build_ast_expr)(void *stmt,
+            isl_ast_build *build,
+            isl_multi_pw_aff *(*fn_index)(
+                __isl_take isl_multi_pw_aff *mpa, isl_id *id,
+                void *user),
+            void *user_index,
+            isl_ast_expr *(*fn_expr)(isl_ast_expr *expr,
+                isl_id *id, void *user),
+        void *user_expr);
+
   struct gpu_prog *prog;
   /* The generated AST. */
   isl_ast_node *tree;
 
   /* The sequence of types for which a definition has been printed. */
   struct gpu_types types;
 
   /* User specified tile, grid and block sizes for each kernel */
int generate_gpu(isl_ctx *ctx, const char *input, FILE *out,
   __isl_give isl_printer *(*print)(__isl_take isl_printer *p,
     struct gpu_prog *prog, __isl_keep isl_ast_node *tree,
     struct gpu_types *types, void *user), void *user);
 
 __isl_give isl_schedule_node *gpu_create_kernel(struct gpu_gen *gen,
   __isl_take isl_schedule_node *node, int scale,
   __isl_keep isl_multi_val *sizes);
 
+__isl_give isl_schedule *get_schedule(struct gpu_gen *gen);
+int has_any_permutable_node(__isl_keep isl_schedule *schedule);
+__isl_give isl_schedule *map_to_device(struct gpu_gen *gen,
+                                       __isl_take isl_schedule *schedule);
+__isl_give isl_ast_node *generate_code(struct gpu_gen *gen,
+                                       __isl_take isl_schedule *schedule);
+
+__isl_give isl_union_set *compute_may_persist(struct gpu_prog *prog);
+void collect_references(struct gpu_prog *prog, struct gpu_array_info *array);
 #endif

lib/External/ppcg/gpu.c

static const char *get_outer_array_name(__isl_keep isl_map *access)
   isl_space_free(space);
 
   return name;
 }
 
 /* Collect all references to the given array and store pointers to them
  * in array->refs.
  */
-static void collect_references(struct gpu_prog *prog,
+void collect_references(struct gpu_prog *prog,
   struct gpu_array_info *array)
 {
   int i;
   int n;
 
   n = 0;
   for (i = 0; i < prog->n_stmts; ++i) {
     struct gpu_stmt *stmt = &prog->stmts[i];

  * The following fields are set in transform_index and used in transform_expr.
  * "array" is the array that is being accessed.
  * "global" is set if the global array is accessed (rather than
  * shared/private memory).
  * "local_array" refers to information on the array specialized
  * to the current kernel.
  */
 struct ppcg_transform_data {
-  struct ppcg_kernel *kernel;
+    struct ppcg_options *options;
+    struct ppcg_kernel *kernel;
   struct gpu_stmt_access *accesses;
   isl_pw_multi_aff *iterator_map;
   isl_pw_multi_aff *sched2copy;
 
   struct gpu_array_info *array;
   int global;
   struct gpu_local_array_info *local_array;
 };

  * These AST expressions are computed from iterator_map,
  * which expresses the domain
  * elements in terms of the generated loops, and sched2copy,
  * which expresses the outer copy_schedule_dim dimensions of
  * the kernel schedule computed by PPCG in terms of the generated loops.
  */
 static __isl_give isl_ast_node *create_domain_leaf(
   struct ppcg_kernel *kernel, __isl_take isl_ast_node *node,
-  __isl_keep isl_ast_build *build, struct gpu_stmt *gpu_stmt)
+  __isl_keep isl_ast_build *build, struct gpu_stmt *gpu_stmt,
+    struct gpu_gen *gen)
 {
   struct ppcg_transform_data data;
   struct ppcg_kernel_stmt *stmt;
   isl_ctx *ctx;
   isl_id *id;
   isl_pw_multi_aff *sched2copy;
   isl_map *map;
   isl_pw_multi_aff *iterator_map;
static __isl_give isl_ast_node *create_domain_leaf(
 
   stmt->type = ppcg_kernel_domain;
   stmt->u.d.stmt = gpu_stmt;
 
   data.kernel = kernel;
   data.accesses = stmt->u.d.stmt->accesses;
   data.iterator_map = iterator_map;
   data.sched2copy = sched2copy;
-  stmt->u.d.ref2expr = pet_stmt_build_ast_exprs(stmt->u.d.stmt->stmt,
+  stmt->u.d.ref2expr = gen->build_ast_expr(stmt->u.d.stmt->stmt,
               build, &transform_index, &data,
               &transform_expr, &data);
 
   isl_pw_multi_aff_free(iterator_map);
   isl_pw_multi_aff_free(sched2copy);
 
   id = isl_id_alloc(ctx, "user", stmt);
   id = isl_id_set_free_user(id, &ppcg_kernel_stmt_free);

 /* Internal data structure for at_domain.
  *
  * "prog" represents the entire scop.
  * "kernel" points to the kernel to which the current schedule node
  * belongs.  It is set by before_mark and reset by after_mark.
  * It may be NULL if we are outside any kernel.
  */
 struct ppcg_at_domain_data {
-  struct gpu_prog *prog;
-  struct ppcg_kernel *kernel;
+    struct gpu_prog *prog;
+    struct gpu_gen *gen;
+    struct ppcg_kernel *kernel;
 };
 
 /* This function is called for each instance of a user statement
  * in the kernel.  This may be one of the original user statements
  * or a statement introduced by PPCG.
  *
  * We first check if the statement id corresponds to a gpu statement,
  * which indicates the statement is an original user statement. Any statement
static __isl_give isl_ast_node *at_domain(__isl_take isl_ast_node *node,
   isl_ast_expr_free(expr);
   isl_ast_expr_free(arg);
 
   gpu_stmt = find_stmt(data->prog, id);
   is_sync = gpu_tree_id_is_sync(id, data->kernel);
   isl_id_free(id);
 
   if (gpu_stmt)
-    return create_domain_leaf(data->kernel, node, build, gpu_stmt);
+    return create_domain_leaf(data->kernel, node, build, gpu_stmt,
+                                  data->gen);
 
   if (!prefixcmp(name, "to_device_") || !prefixcmp(name, "from_device_"))
     return node;
   if (!strcmp(name, "init_device"))
     return build_array_bounds(node, data->prog, build);
   if (!strcmp(name, "clear_device"))
     return node;
   if (is_sync < 0)

 /* Use isl to generate code for both the host and the device
  * from "schedule".
  * The device code is marked by "kernel" mark nodes in the schedule tree,
  * containing a pointer to a ppcg_kernel object.
  * The returned AST only contains the AST for the host code.
  * The ASTs for the device code are embedded in ppcg_kernel objects
  * attached to the leaf nodes that call "kernel".
  */
-static __isl_give isl_ast_node *generate_code(struct gpu_gen *gen,
+__isl_give isl_ast_node *generate_code(struct gpu_gen *gen,
   __isl_take isl_schedule *schedule)
 {
   struct ppcg_at_domain_data data;
   isl_ast_build *build;
   isl_ast_node *tree;
   isl_id_list *iterators;
   int depth;
 
-  data.prog = gen->prog;
+    data.prog = gen->prog;
+    data.gen = gen;
   data.kernel = NULL;
 
   depth = 0;
   if (isl_schedule_foreach_schedule_node_top_down(schedule, &update_depth,
             &depth) < 0)
     return NULL;
   build = isl_ast_build_alloc(gen->prog->ctx);
   iterators = ppcg_scop_generate_names(gen->prog->scop, depth, "c");
if (isl_schedule_node_foreach_descendant_top_down(node, &set_permutable,
     return -1;
 
   return any_parallelism;
 }
 
 /* Does "schedule" contain any permutable band with at least one coincident
  * member?
  */
-static int has_any_permutable_node(__isl_keep isl_schedule *schedule)
+int has_any_permutable_node(__isl_keep isl_schedule *schedule)
 {
   isl_schedule_node *root;
   int any_permutable;
 
   root = isl_schedule_get_root(schedule);
   any_permutable = subtree_has_permutable_bands(root);
   isl_schedule_node_free(root);
 
static __isl_give isl_schedule *compute_or_set_properties(void *user)
   else
     return determine_properties_original_schedule(gen);
 }
 
 /* Obtain a schedule for the scop, by reading it from
  * a file, by computing one or by determining the properties
  * of the original schedule.
  */
-static __isl_give isl_schedule *get_schedule(struct gpu_gen *gen)
+__isl_give isl_schedule *get_schedule(struct gpu_gen *gen)
 {
   return ppcg_get_schedule(gen->ctx, gen->options,
         &compute_or_set_properties, gen);
 }
 
 /* Construct the string "<a>_<b>".
  */
 static char *concat(isl_ctx *ctx, const char *a, const char *b)

  * then children of this node that do not contain any tilable bands
  * are separated from the other children and are not mapped to
  * the device.
  *
  * The GPU code is generated in a context where at least one
  * statement instance is executed.  The corresponding guard is inserted
  * around the entire schedule.
  */
-static __isl_give isl_schedule *map_to_device(struct gpu_gen *gen,
+__isl_give isl_schedule *map_to_device(struct gpu_gen *gen,
   __isl_take isl_schedule *schedule)
 {
   isl_schedule_node *node;
   isl_set *context;
   isl_set *guard;
   isl_union_set *domain;
   isl_union_map *prefix;
   isl_union_pw_multi_aff *contraction;
int generate_gpu(isl_ctx *ctx, const char *input, FILE *out,
   return r;
 }
 
 /* Compute the set of inner array elements that may have their values
  * preserved by "prog".  In particular, collect the array elements of
  * arrays that are not local to "prog" and remove those elements that
  * are definitely killed or definitely written by "prog".
  */
-static __isl_give isl_union_set *compute_may_persist(struct gpu_prog *prog)
+__isl_give isl_union_set *compute_may_persist(struct gpu_prog *prog)
 {
   int i;
   isl_union_set *may_persist, *killed;
   isl_union_map *must_kill;
 
   may_persist = isl_union_set_empty(isl_set_get_space(prog->context));
   for (i = 0; i < prog->n_array; ++i) {
     isl_set *extent;

lib/External/ppcg/opencl.c

-/*
- * Copyright 2013      Ecole Normale Superieure
- *
- * Use of this software is governed by the MIT license
- *
- * Written by Sven Verdoolaege and Riyadh Baghdadi,
- * Ecole Normale Superieure, 45 rue d’Ulm, 75230 Paris, France
- */
-
-#include <ctype.h>
-#include <limits.h>
-#include <string.h>
-
-#include <isl/aff.h>
-#include <isl/ast.h>
-
-#include "opencl.h"
-#include "gpu_print.h"
-#include "gpu.h"
-#include "ppcg.h"
-#include "print.h"
-#include "schedule.h"
-#include "util.h"
-
-#define min(a, b)  (((a) < (b)) ? (a) : (b))
-#define max(a, b)  (((a) > (b)) ? (a) : (b))
-
-/* options are the global options passed to generate_opencl.
- * input is the name of the input file.
- * output is the user-specified output file name and may be NULL
- *  if not specified by the user.
- * kernel_c_name is the name of the kernel_c file.
- * kprinter is an isl_printer for the kernel file.
- * host_c is the generated source file for the host code.  kernel_c is
- * the generated source file for the kernel.
- */
-struct opencl_info {
-  struct ppcg_options *options;
-  const char *input;
-  const char *output;
-  char kernel_c_name[PATH_MAX];
-
-  isl_printer *kprinter;
-
-  FILE *host_c;
-  FILE *kernel_c;
-};
-
-/* Open the file called "name" for writing or print an error message.
- */
-static FILE *open_or_croak(const char *name)
-{
-  FILE *file;
-
-  file = fopen(name, "w");
-  if (!file)
-    fprintf(stderr, "Failed to open \"%s\" for writing\n", name);
-  return file;
-}
-
-/* Open the host .c file and the kernel .h and .cl files for writing.
- * Their names are derived from info->output (or info->input if
- * the user did not specify an output file name).
- * Add the necessary includes to these files, including those specified
- * by the user.
- *
- * Return 0 on success and -1 on failure.
- */
-static int opencl_open_files(struct opencl_info *info)
-{
-  char name[PATH_MAX];
-  int i;
-  int len;
-
-  if (info->output) {
-    const char *ext;
-
-    ext = strrchr(info->output, '.');
-    len = ext ? ext - info->output : strlen(info->output);
-    memcpy(name, info->output, len);
-
-    info->host_c = open_or_croak(info->output);
-  } else {
-    len = ppcg_extract_base_name(name, info->input);
-
-    strcpy(name + len, "_host.c");
-    info->host_c = open_or_croak(name);
-  }
-
-  memcpy(info->kernel_c_name, name, len);
-  strcpy(info->kernel_c_name + len, "_kernel.cl");
-  info->kernel_c = open_or_croak(info->kernel_c_name);
-
-  if (!info->host_c || !info->kernel_c)
-    return -1;
-
-  fprintf(info->host_c, "#include <assert.h>\n");
-  fprintf(info->host_c, "#include <stdio.h>\n");
-  fprintf(info->host_c, "#include \"ocl_utilities.h\"\n");
-  if (info->options->opencl_embed_kernel_code) {
-    fprintf(info->host_c, "#include \"%s\"\n\n",
-      info->kernel_c_name);
-  }
-
-  for (i = 0; i < info->options->opencl_n_include_file; ++i) {
-    info->kprinter = isl_printer_print_str(info->kprinter,
-          "#include <");
-    info->kprinter = isl_printer_print_str(info->kprinter,
-          info->options->opencl_include_files[i]);
-    info->kprinter = isl_printer_print_str(info->kprinter, ">\n");
-  }
-
-  return 0;
-}
-
-/* Write text to a file and escape some special characters that would break a
- * C string.
- */
-static void opencl_print_escaped(const char *str, const char *end, FILE *file)
-{
-  const char *prev = str;
-
-  while ((str = strpbrk(prev, "\"\\")) && str < end) {
-    fwrite(prev, 1, str - prev, file);
-    fprintf(file, "\\%c", *str);
-    prev = str + 1;
-  }
-
-  if (*prev)
-    fwrite(prev, 1, end - prev, file);
-}
-
-/* Write text to a file as a C string literal.
- *
- * This function also prints any characters after the last newline, although
- * normally the input string should end with a newline.
- */
-static void opencl_print_as_c_string(const char *str, FILE *file)
-{
-  const char *prev = str;
-
-  while ((str = strchr(prev, '\n'))) {
-    fprintf(file, "\n\"");
-    opencl_print_escaped(prev, str, file);
-    fprintf(file, "\\n\"");
-
-    prev = str + 1;
-  }
-
-  if (*prev) {
-    fprintf(file, "\n\"");
-    opencl_print_escaped(prev, prev + strlen(prev), file);
-    fprintf(file, "\"");
-  }
-}
-
-/* Write the code that we have accumulated in the kernel isl_printer to the
- * kernel.cl file.  If the opencl_embed_kernel_code option has been set, print
- * the code as a C string literal.  Start that string literal with an empty
- * line, such that line numbers reported by the OpenCL C compiler match those
- * of the kernel file.
- *
- * Return 0 on success and -1 on failure.
- */
-static int opencl_write_kernel_file(struct opencl_info *opencl)
-{
-  char *raw = isl_printer_get_str(opencl->kprinter);
-
-  if (!raw)
-    return -1;
-
-  if (opencl->options->opencl_embed_kernel_code) {
-    fprintf(opencl->kernel_c,
-      "static const char kernel_code[] = \"\\n\"");
-    opencl_print_as_c_string(raw, opencl->kernel_c);
-    fprintf(opencl->kernel_c, ";\n");
-  } else
-    fprintf(opencl->kernel_c, "%s", raw);
-
-  free(raw);
-
-  return 0;
-}
-
-/* Close all output files.  Write the kernel contents to the kernel file before
- * closing it.
- *
- * Return 0 on success and -1 on failure.
- */
-static int opencl_close_files(struct opencl_info *info)
-{
-  int r = 0;
-
-  if (info->kernel_c) {
-    r = opencl_write_kernel_file(info);
-    fclose(info->kernel_c);
-  }
-  if (info->host_c)
-    fclose(info->host_c);
-
-  return r;
-}
-
-static __isl_give isl_printer *opencl_print_host_macros(
-  __isl_take isl_printer *p)
-{
-  const char *macros =
-    "#define openclCheckReturn(ret) \\\n"
-    "  if (ret != CL_SUCCESS) {\\\n"
-    "    fprintf(stderr, \"OpenCL error: %s\\n\", "
-    "opencl_error_string(ret)); \\\n"
-    "    fflush(stderr); \\\n"
-    "    assert(ret == CL_SUCCESS);\\\n  }\n";
-
-  p = isl_printer_start_line(p);
-  p = isl_printer_print_str(p, macros);
-  p = isl_printer_end_line(p);
-
-  return p;
-}
-
-static __isl_give isl_printer *opencl_declare_device_arrays(
-  __isl_take isl_printer *p, struct gpu_prog *prog)
-{
-  int i;
-
-  for (i = 0; i < prog->n_array; ++i) {
-    if (!gpu_array_requires_device_allocation(&prog->array[i]))
-      continue;
-    p = isl_printer_start_line(p);
-    p = isl_printer_print_str(p, "cl_mem dev_");
-    p = isl_printer_print_str(p, prog->array[i].name);
-    p = isl_printer_print_str(p, ";");
-    p = isl_printer_end_line(p);
-  }
-  p = isl_printer_start_line(p);
-  p = isl_printer_end_line(p);
-  return p;
-}
-
-/* Given an array, check whether its positive size guard expression is
- * trivial.
- */
-static int is_array_positive_size_guard_trivial(struct gpu_array_info *array)
-{
-  isl_set *guard;
-  int is_trivial;
-
-  guard = gpu_array_positive_size_guard(array);
-  is_trivial = isl_set_plain_is_universe(guard);
-  isl_set_free(guard);
-  return is_trivial;
-}
-
-/* Allocate a device array for "array'.
- *
- * Emit a max-expression to ensure the device array can contain at least one
- * element if the array's positive size guard expression is not trivial.
- */
-static __isl_give isl_printer *allocate_device_array(__isl_take isl_printer *p,
-  struct gpu_array_info *array)
-{
-  int need_lower_bound;
-
-  need_lower_bound = !is_array_positive_size_guard_trivial(array);
-  if (need_lower_bound)
-    p = ppcg_print_macro(isl_ast_op_max, p);
-
-  p = ppcg_ast_expr_print_macros(array->bound_expr, p);
-  p = ppcg_start_block(p);
-
-  p = isl_printer_start_line(p);
-  p = isl_printer_print_str(p, "dev_");
-  p = isl_printer_print_str(p, array->name);
-  p = isl_printer_print_str(p, " = clCreateBuffer(context, ");
-  p = isl_printer_print_str(p, "CL_MEM_READ_WRITE, ");
-
-  if (need_lower_bound) {
-    p = isl_printer_print_str(p, ppcg_max);
-    p = isl_printer_print_str(p, "(sizeof(");
-    p = isl_printer_print_str(p, array->type);
-    p = isl_printer_print_str(p, "), ");
-  }
-  p = gpu_array_info_print_size(p, array);
-  if (need_lower_bound)
-    p = isl_printer_print_str(p, ")");
-
-  p = isl_printer_print_str(p, ", NULL, &err);");
-  p = isl_printer_end_line(p);
-  p = isl_printer_start_line(p);
-  p = isl_printer_print_str(p, "openclCheckReturn(err);");
-  p = isl_printer_end_line(p);
-
-  p = ppcg_end_block(p);
-
-  return p;
-}
-
-/* Allocate accessed device arrays.
- */
-static __isl_give isl_printer *opencl_allocate_device_arrays(
-  __isl_take isl_printer *p, struct gpu_prog *prog)
-{
-  int i;
-
-  for (i = 0; i < prog->n_array; ++i) {
-    struct gpu_array_info *array = &prog->array[i];
-
-    if (!gpu_array_requires_device_allocation(array))
-      continue;
-
-    p = allocate_device_array(p, array);
-  }
-  p = isl_printer_start_line(p);
-  p = isl_printer_end_line(p);
-  return p;
-}
-
-/* Free the device array corresponding to "array"
- */
-static __isl_give isl_printer *release_device_array(__isl_take isl_printer *p,
-  struct gpu_array_info *array)
-{
-  p = isl_printer_start_line(p);
-  p = isl_printer_print_str(p, "openclCheckReturn("
-          "clReleaseMemObject(dev_");
-  p = isl_printer_print_str(p, array->name);
-  p = isl_printer_print_str(p, "));");
-  p = isl_printer_end_line(p);
-
-  return p;
-}
-
-/* Free the accessed device arrays.
- */
-static __isl_give isl_printer *opencl_release_device_arrays(
-  __isl_take isl_printer *p, struct gpu_prog *prog)
-{
-  int i;
-
-  for (i = 0; i < prog->n_array; ++i) {
-    struct gpu_array_info *array = &prog->array[i];
-    if (!gpu_array_requires_device_allocation(array))
-      continue;
-
-    p = release_device_array(p, array);
-  }
-  return p;
-}
-
-/* Create an OpenCL device, context, command queue and build the kernel.
- * input is the name of the input file provided to ppcg.
- */
-static __isl_give isl_printer *opencl_setup(__isl_take isl_printer *p,
-  const char *input, struct opencl_info *info)
-{
-  p = isl_printer_start_line(p);
-  p = isl_printer_print_str(p, "cl_device_id device;");
-  p = isl_printer_end_line(p);
-  p = isl_printer_start_line(p);
-  p = isl_printer_print_str(p, "cl_context context;");
-  p = isl_printer_end_line(p);
-  p = isl_printer_start_line(p);
-  p = isl_printer_print_str(p, "cl_program program;");
-  p = isl_printer_end_line(p);
-  p = isl_printer_start_line(p);
-  p = isl_printer_print_str(p, "cl_command_queue queue;");
-  p = isl_printer_end_line(p);
-  p = isl_printer_start_line(p);
-  p = isl_printer_print_str(p, "cl_int err;");
-  p = isl_printer_end_line(p);
-  p = isl_printer_start_line(p);
-  p = isl_printer_print_str(p, "device = opencl_create_device(");
-  p = isl_printer_print_int(p, info->options->opencl_use_gpu);
-  p = isl_printer_print_str(p, ");");
-  p = isl_printer_end_line(p);
-  p = isl_printer_start_line(p);
-  p = isl_printer_print_str(p, "context = clCreateContext(NULL, 1, "
-    "&device, NULL, NULL, &err);");
-  p = isl_printer_end_line(p);
-  p = isl_printer_start_line(p);
-  p = isl_printer_print_str(p, "openclCheckReturn(err);");
-  p = isl_printer_end_line(p);
-  p = isl_printer_start_line(p);
-  p = isl_printer_print_str(p, "queue = clCreateCommandQueue"
-          "(context, device, 0, &err);");
-  p = isl_printer_end_line(p);
-  p = isl_printer_start_line(p);
-  p = isl_printer_print_str(p, "openclCheckReturn(err);");
-  p = isl_printer_end_line(p);
-
-  p = isl_printer_start_line(p);
-  p = isl_printer_print_str(p, "program = ");
-
-  if (info->options->opencl_embed_kernel_code) {
-    p = isl_printer_print_str(p, "opencl_build_program_from_string("
-            "context, device, kernel_code, "
-            "sizeof(kernel_code), \"");
-  } else {
-    p = isl_printer_print_str(p, "opencl_build_program_from_file("
-            "context, device, \"");
-    p = isl_printer_print_str(p, info->kernel_c_name);
-    p = isl_printer_print_str(p, "\", \"");
-  }
-
-  if (info->options->opencl_compiler_options)
-    p = isl_printer_print_str(p,
-          info->options->opencl_compiler_options);
-
-  p = isl_printer_print_str(p, "\");");
-  p = isl_printer_end_line(p);
-  p = isl_printer_start_line(p);
-  p = isl_printer_end_line(p);
-
-  return p;
-}
-
-static __isl_give isl_printer *opencl_release_cl_objects(
-  __isl_take isl_printer *p, struct opencl_info *info)
-{
-  p = isl_printer_start_line(p);
-  p = isl_printer_print_str(p, "openclCheckReturn(clReleaseCommandQueue"
-          "(queue));");
-  p = isl_printer_end_line(p);
-  p = isl_printer_start_line(p);
-  p = isl_printer_print_str(p, "openclCheckReturn(clReleaseProgram"
-          "(program));");
-  p = isl_printer_end_line(p);
-  p = isl_printer_start_line(p);
-  p = isl_printer_print_str(p, "openclCheckReturn(clReleaseContext"
-          "(context));");
-  p = isl_printer_end_line(p);
-
-  return p;
-}
-
-/* Print a call to the OpenCL clSetKernelArg() function which sets
- * the arguments of the kernel.  arg_name and arg_index are the name and the
- * index of the kernel argument.  The index of the leftmost argument of
- * the kernel is 0 whereas the index of the rightmost argument of the kernel
- * is n - 1, where n is the total number of the kernel arguments.
- * read_only_scalar is a boolean that indicates whether the argument is a read
- * only scalar.
- */
-static __isl_give isl_printer *opencl_set_kernel_argument(
-  __isl_take isl_printer *p, int kernel_id,
-  const char *arg_name, int arg_index, int read_only_scalar)
-{
-  p = isl_printer_start_line(p);
-  p = isl_printer_print_str(p,
-    "openclCheckReturn(clSetKernelArg(kernel");
-  p = isl_printer_print_int(p, kernel_id);
-  p = isl_printer_print_str(p, ", ");
-  p = isl_printer_print_int(p, arg_index);
-  p = isl_printer_print_str(p, ", sizeof(");
-
-  if (read_only_scalar) {
-    p = isl_printer_print_str(p, arg_name);
-    p = isl_printer_print_str(p, "), &");
-  } else
-    p = isl_printer_print_str(p, "cl_mem), (void *) &dev_");
-
-  p = isl_printer_print_str(p, arg_name);
-  p = isl_printer_print_str(p, "));");
-  p = isl_printer_end_line(p);
-
-  return p;
-}
-
-/* Print the block sizes as a list of the sizes in each
- * dimension.
- */
-static __isl_give isl_printer *opencl_print_block_sizes(
-  __isl_take isl_printer *p, struct ppcg_kernel *kernel)
-{
-  int i;
-
-  if (kernel->n_block > 0)
-    for (i = 0; i < kernel->n_block; ++i) {
-      if (i)
-        p = isl_printer_print_str(p, ", ");
-      p = isl_printer_print_int(p, kernel->block_dim[i]);
-    }
-  else
-    p = isl_printer_print_str(p, "1");
-
-  return p;
-}
-
-/* Set the arguments of the OpenCL kernel by printing a call to the OpenCL
- * clSetKernelArg() function for each kernel argument.
- */
-static __isl_give isl_printer *opencl_set_kernel_arguments(
-  __isl_take isl_printer *p, struct gpu_prog *prog,
-  struct ppcg_kernel *kernel)
-{
-  int i, n, ro;
-  unsigned nparam;
-  isl_space *space;
-  int arg_index = 0;
-
-  for (i = 0; i < prog->n_array; ++i) {
-    int required;
-
-    required = ppcg_kernel_requires_array_argument(kernel, i);
-    if (required < 0)
-      return isl_printer_free(p);
-    if (!required)
-      continue;
-    ro = gpu_array_is_read_only_scalar(&prog->array[i]);
-    opencl_set_kernel_argument(p, kernel->id, prog->array[i].name,
-      arg_index, ro);
-    arg_index++;
-  }
-
-  space = isl_union_set_get_space(kernel->arrays);
-  nparam = isl_space_dim(space, isl_dim_param);
-  for (i = 0; i < nparam; ++i) {
-    const char *name;
-
-    name = isl_space_get_dim_name(space, isl_dim_param, i);
-    opencl_set_kernel_argument(p, kernel->id, name, arg_index, 1);
-    arg_index++;
-  }
-  isl_space_free(space);
-
-  n = isl_space_dim(kernel->space, isl_dim_set);
-  for (i = 0; i < n; ++i) {
-    const char *name;
-
-    name = isl_space_get_dim_name(kernel->space, isl_dim_set, i);
-    opencl_set_kernel_argument(p, kernel->id, name, arg_index, 1);
-    arg_index++;
-  }
-
-  return p;
-}
-
-/* Print the arguments to a kernel declaration or call.  If "types" is set,
- * then print a declaration (including the types of the arguments).
- *
- * The arguments are printed in the following order
- * - the arrays accessed by the kernel
- * - the parameters
- * - the host loop iterators
- */
-static __isl_give isl_printer *opencl_print_kernel_arguments(
-  __isl_take isl_printer *p, struct gpu_prog *prog,
-  struct ppcg_kernel *kernel, int types)
-{
-  int i, n;
-  int first = 1;
-  unsigned nparam;
-  isl_space *space;
-  const char *type;
-
-  for (i = 0; i < prog->n_array; ++i) {
-    int required;
-
-    required = ppcg_kernel_requires_array_argument(kernel, i);
-    if (required < 0)
-      return isl_printer_free(p);
-    if (!required)
-      continue;
-
-    if (!first)
-      p = isl_printer_print_str(p, ", ");
-
-    if (types)
-      p = gpu_array_info_print_declaration_argument(p,
-        &prog->array[i], "__global");
-    else
-      p = gpu_array_info_print_call_argument(p,
-        &prog->array[i]);
-
-    first = 0;
-  }
-
-  space = isl_union_set_get_space(kernel->arrays);
-  nparam = isl_space_dim(space, isl_dim_param);
-  for (i = 0; i < nparam; ++i) {
-    const char *name;
-
-    name = isl_space_get_dim_name(space, isl_dim_param, i);
-
-    if (!first)
-      p = isl_printer_print_str(p, ", ");
-    if (types)
-      p = isl_printer_print_str(p, "int ");
-    p = isl_printer_print_str(p, name);
-
-    first = 0;
-  }
-  isl_space_free(space);
-
-  n = isl_space_dim(kernel->space, isl_dim_set);
-  type = isl_options_get_ast_iterator_type(prog->ctx);
-  for (i = 0; i < n; ++i) {
-    const char *name;
-
-    if (!first)
-      p = isl_printer_print_str(p, ", ");
-    name = isl_space_get_dim_name(kernel->space, isl_dim_set, i);
-    if (types) {
-      p = isl_printer_print_str(p, type);
-      p = isl_printer_print_str(p, " ");
-    }
-    p = isl_printer_print_str(p, name);
-
-    first = 0;
-  }
-
-  return p;
-}
-
-/* Print the header of the given kernel.
- */
-static __isl_give isl_printer *opencl_print_kernel_header(
-  __isl_take isl_printer *p, struct gpu_prog *prog,
-  struct ppcg_kernel *kernel)
-{
-  p = isl_printer_start_line(p);
-  p = isl_printer_print_str(p, "__kernel void kernel");
-  p = isl_printer_print_int(p, kernel->id);
-  p = isl_printer_print_str(p, "(");
-  p = opencl_print_kernel_arguments(p, prog, kernel, 1);
-  p = isl_printer_print_str(p, ")");
-  p = isl_printer_end_line(p);
-
-  return p;
-}
-
-/* Print a list of iterators of type "type" with names "ids" to "p".
- * Each iterator is assigned the corresponding opencl identifier returned
- * by the function "opencl_id".
- * Unlike the equivalent function in the CUDA backend which prints iterators
- * in reverse order to promote coalescing, this function does not print
- * iterators in reverse order.  The OpenCL backend currently does not take
- * into account any coalescing considerations.
- */
-static __isl_give isl_printer *print_iterators(__isl_take isl_printer *p,
-  const char *type, __isl_keep isl_id_list *ids, const char *opencl_id)
-{
-  int i, n;
-
-  n = isl_id_list_n_id(ids);
-  if (n <= 0)
-    return p;
-  p = isl_printer_start_line(p);
-  p = isl_printer_print_str(p, type);
-  p = isl_printer_print_str(p, " ");
-  for (i = 0; i < n; ++i) {
-    isl_id *id;
-
-    if (i)
-      p = isl_printer_print_str(p, ", ");
-    id = isl_id_list_get_id(ids, i);
-    p = isl_printer_print_id(p, id);
-    isl_id_free(id);
-    p = isl_printer_print_str(p, " = ");
-    p = isl_printer_print_str(p, opencl_id);
-    p = isl_printer_print_str(p, "(");
-    p = isl_printer_print_int(p, i);
-    p = isl_printer_print_str(p, ")");
-  }
-  p = isl_printer_print_str(p, ";");
-  p = isl_printer_end_line(p);
-
-  return p;
-}
-
-static __isl_give isl_printer *opencl_print_kernel_iterators(
-  __isl_take isl_printer *p, struct ppcg_kernel *kernel)
-{
-  isl_ctx *ctx = isl_ast_node_get_ctx(kernel->tree);
-  const char *type;
-
-  type = isl_options_get_ast_iterator_type(ctx);
-
-  p = print_iterators(p, type, kernel->block_ids, "get_group_id");
-  p = print_iterators(p, type, kernel->thread_ids, "get_local_id");
-
-  return p;
-}
-
-static __isl_give isl_printer *opencl_print_kernel_var(
-  __isl_take isl_printer *p, struct ppcg_kernel_var *var)
-{
-  int j;
-  isl_val *v;
-
-  p = isl_printer_start_line(p);
-  if (var->type == ppcg_access_shared)
-    p = isl_printer_print_str(p, "__local ");
-  p = isl_printer_print_str(p, var->array->type);
-  p = isl_printer_print_str(p, " ");
-  p = isl_printer_print_str(p, var->name);
-  for (j = 0; j < var->array->n_index; ++j) {
-    p = isl_printer_print_str(p, "[");
-    v = isl_vec_get_element_val(var->size, j);
-    p = isl_printer_print_val(p, v);
-    p = isl_printer_print_str(p, "]");
-    isl_val_free(v);
-  }
-  p = isl_printer_print_str(p, ";");
-  p = isl_printer_end_line(p);
-
-  return p;
-}
-
-static __isl_give isl_printer *opencl_print_kernel_vars(
-    __isl_take isl_printer *p, struct ppcg_kernel *kernel)
-{
-  int i;
-
-  for (i = 0; i < kernel->n_var; ++i)
-    p = opencl_print_kernel_var(p, &kernel->var[i]);
-
-  return p;
-}
-
-/* Print a call to barrier() which is a sync statement.
- * All work-items in a work-group executing the kernel on a processor must
- * execute the barrier() function before any are allowed to continue execution
- * beyond the barrier.
- * The flag CLK_LOCAL_MEM_FENCE makes the barrier function either flush any
- * variables stored in local memory or queue a memory fence to ensure correct
- * ordering of memory operations to local memory.
- * The flag CLK_GLOBAL_MEM_FENCE makes the barrier function queue a memory
- * fence to ensure correct ordering of memory operations to global memory.
- */
-static __isl_give isl_printer *opencl_print_sync(__isl_take isl_printer *p,
-  struct ppcg_kernel_stmt *stmt)
-{
-  p = isl_printer_start_line(p);
-  p = isl_printer_print_str(p,
-    "barrier(CLK_LOCAL_MEM_FENCE | CLK_GLOBAL_MEM_FENCE);");
-  p = isl_printer_end_line(p);
-
-  return p;
-}
-
-/* Data structure containing function names for which the calls
- * should be changed from
- *
- *  name(arg)
- *
- * to
- *
- *  opencl_name((type) (arg))
- */
-static struct ppcg_opencl_fn {
-  const char *name;
-  const char *opencl_name;
-  const char *type;
-} opencl_fn[] = {
-  { "expf", "exp",    "float" },
-  { "powf", "pow",    "float" },
-  { "sqrtf",  "sqrt",   "float" },
-};
-
-#define ARRAY_SIZE(array) (sizeof(array)/sizeof(*array))
-
-/* If the name of function called by "expr" matches any of those
- * in ppcg_opencl_fn, then replace the call by a cast to the corresponding
- * type in ppcg_opencl_fn and a call to corresponding OpenCL function.
- */
-static __isl_give pet_expr *map_opencl_call(__isl_take pet_expr *expr,
-  void *user)
-{
-  const char *name;
-  int i;
-
-  name = pet_expr_call_get_name(expr);
-  for (i = 0; i < ARRAY_SIZE(opencl_fn); ++i) {
-    pet_expr *arg;
-
-    if (strcmp(name, opencl_fn[i].name))
-      continue;
-    expr = pet_expr_call_set_name(expr, opencl_fn[i].opencl_name);
-    arg = pet_expr_get_arg(expr, 0);
-    arg = pet_expr_new_cast(opencl_fn[i].type, arg);
-    expr = pet_expr_set_arg(expr, 0, arg);
-  }
-  return expr;
-}
-
-/* Print the body of a statement from the input program,
- * for use in OpenCL code.
- *
- * Before calling ppcg_kernel_print_domain to print the actual statement body,
- * we first modify this body to take into account that the output code
- * is OpenCL code.  In particular, if the statement calls any function
- * with a "f" suffix, then it needs to be replaced by a call to
- * the corresponding function without suffix after casting the argument
- * to a float.
- */
-static __isl_give isl_printer *print_opencl_kernel_domain(
-  __isl_take isl_printer *p, struct ppcg_kernel_stmt *stmt)
-{
-  struct pet_stmt *ps;
-  pet_tree *tree;
-
-  ps = stmt->u.d.stmt->stmt;
-  tree = pet_tree_copy(ps->body);
-  ps->body = pet_tree_map_call_expr(ps->body, &map_opencl_call, NULL);
-  p = ppcg_kernel_print_domain(p, stmt);
-  pet_tree_free(ps->body);
-  ps->body = tree;
-
-  return p;
-}
-
-/* This function is called for each user statement in the AST,
- * i.e., for each kernel body statement, copy statement or sync statement.
- */
-static __isl_give isl_printer *opencl_print_kernel_stmt(
-  __isl_take isl_printer *p,
-  __isl_take isl_ast_print_options *print_options,
-  __isl_keep isl_ast_node *node, void *user)
-{
-  isl_id *id;
-  struct ppcg_kernel_stmt *stmt;
-
-  id = isl_ast_node_get_annotation(node);
-  stmt = isl_id_get_user(id);
-  isl_id_free(id);
-
-  isl_ast_print_options_free(print_options);
-
-  switch (stmt->type) {
-  case ppcg_kernel_copy:
-    return ppcg_kernel_print_copy(p, stmt);
-  case ppcg_kernel_sync:
-    return opencl_print_sync(p, stmt);
-  case ppcg_kernel_domain:
-    return print_opencl_kernel_domain(p, stmt);
-  }
-
-  return p;
-}
-
-/* Return true if there is a double array in prog->array or
- * if any of the types in prog->scop involve any doubles.
- * To check the latter condition, we simply search for the string "double"
- * in the type definitions, which may result in false positives.
- */
-static __isl_give int any_double_elements(struct gpu_prog *prog)
-{
-  int i;
-
-  for (i = 0; i < prog->n_array; ++i)
-    if (strcmp(prog->array[i].type, "double") == 0)
-      return 1;
-
-  for (i = 0; i < prog->scop->pet->n_type; ++i) {
-    struct pet_type *type = prog->scop->pet->types[i];
-
-    if (strstr(type->definition, "double"))
-      return 1;
-  }
-
-  return 0;
-}
-
-/* Prints a #pragma to enable support for double floating-point
- * precision.  OpenCL 1.0 adds support for double precision floating-point as
- * an optional extension. An application that wants to use double will need to
- * include the #pragma OPENCL EXTENSION cl_khr_fp64 : enable directive before
- * any double precision data type is declared in the kernel code.
- */
-static __isl_give isl_printer *opencl_enable_double_support(
-  __isl_take isl_printer *p)
-{
-  p = isl_printer_start_line(p);
-  p = isl_printer_print_str(p, "#pragma OPENCL EXTENSION cl_khr_fp64 :"
-    " enable");
-  p = isl_printer_end_line(p);
-  p = isl_printer_start_line(p);
-  p = isl_printer_end_line(p);
-
-  return p;
-}
-
-/* Macro definitions for ppcg_min and ppcg_max for use
- * in OpenCL kernel code.
- * These macro definitions essentially call the corresponding
- * OpenCL macros/functions, but first ensure that the two arguments
- * have the same type, since the OpenCL versions are only defined
- * in case those arguments have the same type.
- */
-static const char *opencl_min =
-  "(x,y)    min((__typeof__(x + y)) x, (__typeof__(x + y)) y)";
-static const char *opencl_max =
-  "(x,y)    max((__typeof__(x + y)) x, (__typeof__(x + y)) y)";
-
-/* Set the macro definitions for ppcg_min and ppcg_max to
- * OpenCL specific versions.
- */
-static __isl_give isl_printer *set_opencl_macros(__isl_take isl_printer *p)
-{
-  return ppcg_set_macros(p, opencl_min, opencl_max);
-}
-
-static __isl_give isl_printer *opencl_print_kernel(struct gpu_prog *prog,
-  struct ppcg_kernel *kernel, __isl_take isl_printer *p)
-{
-  isl_ctx *ctx = isl_ast_node_get_ctx(kernel->tree);
-  isl_ast_print_options *print_options;
-
-  print_options = isl_ast_print_options_alloc(ctx);
-  print_options = isl_ast_print_options_set_print_user(print_options,
-        &opencl_print_kernel_stmt, NULL);
-
-  p = isl_printer_set_output_format(p, ISL_FORMAT_C);
-  p = opencl_print_kernel_header(p, prog, kernel);
-  p = isl_printer_print_str(p, "{");
-  p = isl_printer_end_line(p);
-  p = isl_printer_indent(p, 4);
-  p = opencl_print_kernel_iterators(p, kernel);
-  p = opencl_print_kernel_vars(p, kernel);
-  p = isl_printer_end_line(p);
-  p = ppcg_set_macro_names(p);
-  p = set_opencl_macros(p);
-  p = gpu_print_macros(p, kernel->tree);
-  p = isl_ast_node_print(kernel->tree, p, print_options);
-  p = isl_printer_indent(p, -4);
-  p = isl_printer_start_line(p);
-  p = isl_printer_print_str(p, "}");
-  p = isl_printer_end_line(p);
-
-  return p;
-}
-
-struct print_host_user_data_opencl {
-  struct opencl_info *opencl;
-  struct gpu_prog *prog;
-};
-
-/* This function prints the i'th block size multiplied by the i'th grid size,
- * where i (a parameter to this function) is one of the possible dimensions of
- * grid sizes and block sizes.
- * If the dimension of block sizes is not equal to the dimension of grid sizes
- * the output is calculated as follows:
- *
- * Suppose that:
- * block_sizes[dim1] is the list of blocks sizes and it contains dim1 elements.
- * grid_sizes[dim2] is the list of grid sizes and it contains dim2 elements.
- *
- * The output is:
- * If (i > dim2) then the output is block_sizes[i]
- * If (i > dim1) then the output is grid_sizes[i]
- */
-static __isl_give isl_printer *opencl_print_total_number_of_work_items_for_dim(
-  __isl_take isl_printer *p, struct ppcg_kernel *kernel, int i)
-{
-  int grid_dim, block_dim;
-  isl_ast_expr *grid_size_expr;
-  isl_ast_expr *bound_grid;
-
-  grid_dim = isl_multi_pw_aff_dim(kernel->grid_size, isl_dim_set);
-  block_dim = kernel->n_block;
-
-  if (i < min(grid_dim, block_dim)) {
-    grid_size_expr = kernel->grid_size_expr;
-    bound_grid = isl_ast_expr_get_op_arg(grid_size_expr, 1 + i);
-    p = isl_printer_print_str(p, "(");
-    p = isl_printer_print_ast_expr(p, bound_grid);
-    p = isl_printer_print_str(p, ") * ");
-    p = isl_printer_print_int(p, kernel->block_dim[i]);
-    isl_ast_expr_free(bound_grid);
-  } else if (i >= grid_dim) {
-    p = isl_printer_print_int(p, kernel->block_dim[i]);
-  } else {
-    grid_size_expr = kernel->grid_size_expr;
-    bound_grid = isl_ast_expr_get_op_arg(grid_size_expr, 1 + i);
-    p = isl_printer_print_ast_expr(p, bound_grid);
-    isl_ast_expr_free(bound_grid);
-  }
-
-  return p;
-}
-
-/* Print a list that represents the total number of work items.  The list is
- * constructed by performing an element-wise multiplication of the block sizes
- * and the grid sizes.  To explain how the list is constructed, suppose that:
- * block_sizes[dim1] is the list of blocks sizes and it contains dim1 elements.
- * grid_sizes[dim2] is the list of grid sizes and it contains dim2 elements.
- *
- * The output of this function is constructed as follows:
- * If (dim1 > dim2) then the output is the following list:
- * grid_sizes[0]*block_sizes[0], ..., grid_sizes[dim2-1]*block_sizes[dim2-1],
- * block_sizes[dim2], ..., block_sizes[dim1-2], block_sizes[dim1-1].
- *
- * If (dim2 > dim1) then the output is the following list:
- * grid_sizes[0]*block_sizes[0], ..., grid_sizes[dim1-1] * block_sizes[dim1-1],
- * grid_sizes[dim1], grid_sizes[dim2-2], grid_sizes[dim2-1].
- *
- * To calculate the total number of work items out of the list constructed by
- * this function, the user should multiply the elements of the list.
- */
-static __isl_give isl_printer *opencl_print_total_number_of_work_items_as_list(
-  __isl_take isl_printer *p, struct ppcg_kernel *kernel)
-{
-  int i;
-  int grid_dim, block_dim;
-
-  grid_dim = isl_multi_pw_aff_dim(kernel->grid_size, isl_dim_set);
-  block_dim = kernel->n_block;
-
-  if ((grid_dim <= 0) || (block_dim <= 0)) {
-    p = isl_printer_print_str(p, "1");
-    return p;
-  }
-
-  for (i = 0; i <= max(grid_dim, block_dim) - 1; i++) {
-    if (i > 0)
-      p = isl_printer_print_str(p, ", ");
-
-    p = opencl_print_total_number_of_work_items_for_dim(p,
-      kernel, i);
-  }
-
-  return p;
-}
-
-/* Copy "array" from the host to the device (to_host = 0) or
- * back from the device to the host (to_host = 1).
- */
-static __isl_give isl_printer *copy_array(__isl_take isl_printer *p,
-  struct gpu_array_info *array, int to_host)
-{
-  p = isl_printer_start_line(p);
-  p = isl_printer_print_str(p, "openclCheckReturn(");
-  if (to_host)
-    p = isl_printer_print_str(p, "clEnqueueReadBuffer");
-  else
-    p = isl_printer_print_str(p, "clEnqueueWriteBuffer");
-  p = isl_printer_print_str(p, "(queue, dev_");
-  p = isl_printer_print_str(p, array->name);
-  p = isl_printer_print_str(p, ", CL_TRUE, 0, ");
-  p = gpu_array_info_print_size(p, array);
-
-  if (gpu_array_is_scalar(array))
-    p = isl_printer_print_str(p, ", &");
-  else
-    p = isl_printer_print_str(p, ", ");
-  p = isl_printer_print_str(p, array->name);
-  p = isl_printer_print_str(p, ", 0, NULL, NULL));");
-  p = isl_printer_end_line(p);
-
-  return p;
-}
-
-/* Print code for initializing the device for execution of the transformed
- * code.  This includes declaring locally defined variables as well as
- * declaring and allocating the required copies of arrays on the device.
- */
-static __isl_give isl_printer *init_device(__isl_take isl_printer *p,
-  struct gpu_prog *prog, struct opencl_info *opencl)
-{
-  p = opencl_print_host_macros(p);
-
-  p = gpu_print_local_declarations(p, prog);
-  p = opencl_declare_device_arrays(p, prog);
-  p = opencl_setup(p, opencl->input, opencl);
-  p = opencl_allocate_device_arrays(p, prog);
-
-  return p;
-}
-
-/* Print code for clearing the device after execution of the transformed code.
- * In particular, free the memory that was allocated on the device.
- */
-static __isl_give isl_printer *clear_device(__isl_take isl_printer *p,
-  struct gpu_prog *prog, struct opencl_info *opencl)
-{
-  p = opencl_release_device_arrays(p, prog);
-  p = opencl_release_cl_objects(p, opencl);
-
-  return p;
-}
-
-/* Print a statement for copying an array to or from the device,
- * or for initializing or clearing the device.
- * The statement identifier of a copying node is called
- * "to_device_<array name>" or "from_device_<array name>" and
- * its user pointer points to the gpu_array_info of the array
- * that needs to be copied.
- * The node for initializing the device is called "init_device".
- * The node for clearing the device is called "clear_device".
- *
- * Extract the array (if any) from the identifier and call
- * init_device, clear_device, copy_array_to_device or copy_array_from_device.
- */
-static __isl_give isl_printer *print_device_node(__isl_take isl_printer *p,
-  __isl_keep isl_ast_node *node, struct gpu_prog *prog,
-  struct opencl_info *opencl)
-{
-  isl_ast_expr *expr, *arg;
-  isl_id *id;
-  const char *name;
-  struct gpu_array_info *array;
-
-  expr = isl_ast_node_user_get_expr(node);
-  arg = isl_ast_expr_get_op_arg(expr, 0);
-  id = isl_ast_expr_get_id(arg);
-  name = isl_id_get_name(id);
-  array = isl_id_get_user(id);
-  isl_id_free(id);
-  isl_ast_expr_free(arg);
-  isl_ast_expr_free(expr);
-
-  if (!name)
-    return isl_printer_free(p);
-  if (!strcmp(name, "init_device"))
-    return init_device(p, prog, opencl);
-  if (!strcmp(name, "clear_device"))
-    return clear_device(p, prog, opencl);
-  if (!array)
-    return isl_printer_free(p);
-
-  if (!prefixcmp(name, "to_device"))
-    return copy_array(p, array, 0);
-  else
-    return copy_array(p, array, 1);
-}
-
-/* Print the user statement of the host code to "p".
- *
- * The host code may contain original user statements, kernel launches,
- * statements that copy data to/from the device and statements
- * the initialize or clear the device.
- * The original user statements and the kernel launches have
- * an associated annotation, while the other statements do not.
- * The latter are handled by print_device_node.
- * The annotation on the user statements is called "user".
- *
- * In case of a kernel launch, print a block of statements that
- * defines the grid and the work group and then launches the kernel.
- *
- * A grid is composed of many work groups (blocks), each work group holds
- * many work-items (threads).
- *
- * global_work_size[kernel->n_block] represents the total number of work
- * items.  It points to an array of kernel->n_block unsigned
- * values that describe the total number of work-items that will execute
- * the kernel.  The total number of work-items is computed as:
- * global_work_size[0] *...* global_work_size[kernel->n_block - 1].
- *
- * The size of each work group (i.e. the number of work-items in each work
- * group) is described using block_size[kernel->n_block].  The total
- * number of work-items in a block (work-group) is computed as:
- * block_size[0] *... * block_size[kernel->n_block - 1].
- *
- * For more information check:
- * http://www.khronos.org/registry/cl/sdk/1.0/docs/man/xhtml/clEnqueueNDRangeKernel.html
- */
-static __isl_give isl_printer *opencl_print_host_user(
-  __isl_take isl_printer *p,
-  __isl_take isl_ast_print_options *print_options,
-  __isl_keep isl_ast_node *node, void *user)
-{
-  isl_id *id;
-  int is_user;
-  struct ppcg_kernel *kernel;
-  struct ppcg_kernel_stmt *stmt;
-  struct print_host_user_data_opencl *data;
-
-  isl_ast_print_options_free(print_options);
-
-  data = (struct print_host_user_data_opencl *) user;
-
-  id = isl_ast_node_get_annotation(node);
-  if (!id)
-    return print_device_node(p, node, data->prog, data->opencl);
-
-  is_user = !strcmp(isl_id_get_name(id), "user");
-  kernel = is_user ? NULL : isl_id_get_user(id);
-  stmt = is_user ? isl_id_get_user(id) : NULL;
-  isl_id_free(id);
-
-  if (is_user)
-    return ppcg_kernel_print_domain(p, stmt);
-
-  p = isl_printer_start_line(p);
-  p = isl_printer_print_str(p, "{");
-  p = isl_printer_end_line(p);
-  p = isl_printer_indent(p, 2);
-
-  p = isl_printer_start_line(p);
-  p = isl_printer_print_str(p, "size_t global_work_size[");
-
-  if (kernel->n_block > 0)
-    p = isl_printer_print_int(p, kernel->n_block);
-  else
-    p = isl_printer_print_int(p, 1);
-
-  p = isl_printer_print_str(p, "] = {");
-  p = opencl_print_total_number_of_work_items_as_list(p, kernel);
-  p = isl_printer_print_str(p, "};");
-  p = isl_printer_end_line(p);
-
-  p = isl_printer_start_line(p);
-  p = isl_printer_print_str(p, "size_t block_size[");
-
-  if (kernel->n_block > 0)
-    p = isl_printer_print_int(p, kernel->n_block);
-  else
-    p = isl_printer_print_int(p, 1);
-
-  p = isl_printer_print_str(p, "] = {");
-  p = opencl_print_block_sizes(p, kernel);
-  p = isl_printer_print_str(p, "};");
-  p = isl_printer_end_line(p);
-
-  p = isl_printer_start_line(p);
-  p = isl_printer_print_str(p, "cl_kernel kernel");
-  p = isl_printer_print_int(p, kernel->id);
-  p = isl_printer_print_str(p, " = clCreateKernel(program, \"kernel");
-  p = isl_printer_print_int(p, kernel->id);
-  p = isl_printer_print_str(p, "\", &err);");
-  p = isl_printer_end_line(p);
-  p = isl_printer_start_line(p);
-  p = isl_printer_print_str(p, "openclCheckReturn(err);");
-  p = isl_printer_end_line(p);
-
-  opencl_set_kernel_arguments(p, data->prog, kernel);
-
-  p = isl_printer_start_line(p);
-  p = isl_printer_print_str(p, "openclCheckReturn(clEnqueueNDRangeKernel"
-    "(queue, kernel");
-  p = isl_printer_print_int(p, kernel->id);
-  p = isl_printer_print_str(p, ", ");
-  if (kernel->n_block > 0)
-    p = isl_printer_print_int(p, kernel->n_block);
-  else
-    p = isl_printer_print_int(p, 1);
-
-  p = isl_printer_print_str(p, ", NULL, global_work_size, "
-          "block_size, "
-          "0, NULL, NULL));");
-  p = isl_printer_end_line(p);
-  p = isl_printer_start_line(p);
-  p = isl_printer_print_str(p, "openclCheckReturn("
-          "clReleaseKernel(kernel");
-  p = isl_printer_print_int(p, kernel->id);
-  p = isl_printer_print_str(p, "));");
-  p = isl_printer_end_line(p);
-  p = isl_printer_start_line(p);
-  p = isl_printer_print_str(p, "clFinish(queue);");
-  p = isl_printer_end_line(p);
-  p = isl_printer_indent(p, -2);
-  p = isl_printer_start_line(p);
-  p = isl_printer_print_str(p, "}");
-  p = isl_printer_end_line(p);
-
-  p = isl_printer_start_line(p);
-  p = isl_printer_end_line(p);
-
-  data->opencl->kprinter = opencl_print_kernel(data->prog, kernel,
-            data->opencl->kprinter);
-
-  return p;
-}
-
-static __isl_give isl_printer *opencl_print_host_code(
-  __isl_take isl_printer *p, struct gpu_prog *prog,
-  __isl_keep isl_ast_node *tree, struct opencl_info *opencl)
-{
-  isl_ast_print_options *print_options;
-  isl_ctx *ctx = isl_ast_node_get_ctx(tree);
-  struct print_host_user_data_opencl data = { opencl, prog };
-
-  print_options = isl_ast_print_options_alloc(ctx);
-  print_options = isl_ast_print_options_set_print_user(print_options,
-        &opencl_print_host_user, &data);
-
-  p = gpu_print_macros(p, tree);
-  p = isl_ast_node_print(tree, p, print_options);
-
-  return p;
-}
-
-/* Given a gpu_prog "prog" and the corresponding transformed AST
- * "tree", print the entire OpenCL code to "p".
- */
-static __isl_give isl_printer *print_opencl(__isl_take isl_printer *p,
-  struct gpu_prog *prog, __isl_keep isl_ast_node *tree,
-  struct gpu_types *types, void *user)
-{
-  struct opencl_info *opencl = user;
-
-  opencl->kprinter = isl_printer_set_output_format(opencl->kprinter,
-              ISL_FORMAT_C);
-  if (any_double_elements(prog))
-    opencl->kprinter = opencl_enable_double_support(
-              opencl->kprinter);
-  if (opencl->options->opencl_print_kernel_types)
-    opencl->kprinter = gpu_print_types(opencl->kprinter, types,
-                prog);
-
-  if (!opencl->kprinter)
-    return isl_printer_free(p);
-
-  p = opencl_print_host_code(p, prog, tree, opencl);
-
-  return p;
-}
-
-/* Transform the code in the file called "input" by replacing
- * all scops by corresponding OpenCL code.
- * The host code is written to "output" or a name derived from
- * "input" if "output" is NULL.
- * The kernel code is placed in separate files with names
- * derived from "output" or "input".
- *
- * We let generate_gpu do all the hard work and then let it call
- * us back for printing the AST in print_opencl.
- *
- * To prepare for this printing, we first open the output files
- * and we close them after generate_gpu has finished.
- */
-int generate_opencl(isl_ctx *ctx, struct ppcg_options *options,
-  const char *input, const char *output)
-{
-  struct opencl_info opencl = { options, input, output };
-  int r;
-
-  opencl.kprinter = isl_printer_to_str(ctx);
-  r = opencl_open_files(&opencl);
-
-  if (r >= 0)
-    r = generate_gpu(ctx, input, opencl.host_c, options,
-        &print_opencl, &opencl);
-
-  if (opencl_close_files(&opencl) < 0)
-    r = -1;
-  isl_printer_free(opencl.kprinter);
-
-  return r;
-}

lib/External/ppcg/ppcg.h

int ppcg_transform(isl_ctx *ctx, const char *input, FILE *out,
   struct ppcg_options *options,
   __isl_give isl_printer *(*fn)(__isl_take isl_printer *p,
     struct ppcg_scop *scop, void *user), void *user);
 
 __isl_give isl_schedule *ppcg_compute_schedule(
   __isl_take isl_schedule_constraints *sc,
   __isl_keep isl_schedule *schedule, struct ppcg_options *options);
 
+void compute_tagger(struct ppcg_scop *ps);
+void compute_dependences(struct ppcg_scop *scop);
+void eliminate_dead_code(struct ppcg_scop *ps);
+void *ppcg_scop_free(struct ppcg_scop *ps);
 #endif

lib/External/ppcg/ppcg.c

  */
 int ppcg_scop_any_hidden_declarations(struct ppcg_scop *scop)
 {
   int i;
 
   if (!scop)
     return 0;
 
+    // This is a pet feature not available in Polly.
+    return 0;
+
   for (i = 0; i < scop->pet->n_array; ++i)
     if (scop->pet->arrays[i]->declared &&
         !scop->pet->arrays[i]->exposed)
       return 1;
 
   return 0;
 }
 

  * the reference tags that appear in any of the reads, writes or kills.
  * Store the result in ps->tagger.
  *
  * For example, if the statement with iteration space S[i,j]
  * contains two array references R_1[] and R_2[], then ps->tagger will contain
  *
  *  { [S[i,j] -> R_1[]] -> S[i,j]; [S[i,j] -> R_2[]] -> S[i,j] }
  */
-static void compute_tagger(struct ppcg_scop *ps)
+void compute_tagger(struct ppcg_scop *ps)
 {
   isl_union_map *tagged;
   isl_union_pw_multi_aff *tagger;
 
   tagged = isl_union_map_copy(ps->tagged_reads);
   tagged = isl_union_map_union(tagged,
         isl_union_map_copy(ps->tagged_may_writes));
   tagged = isl_union_map_union(tagged,

  * scop->live_in.
  * Store the potential live out accesses in scop->live_out.
  * Store the potential false (anti and output) dependences in scop->dep_false.
  *
  * If live range reordering is allowed, then we compute a separate
  * set of order dependences and a set of external false dependences
  * in compute_live_range_reordering_dependences.
  */
-static void compute_dependences(struct ppcg_scop *scop)
+void compute_dependences(struct ppcg_scop *scop)
 {
   isl_union_map *may_source;
   isl_union_access_info *access;
   isl_union_flow *flow;
 
   if (!scop)
     return;
 

  *
  * Then we add those statement iterations that produce
  * something needed by the "live" statements iterations.
  * We keep doing this until no more statement iterations can be added.
  * To ensure that the procedure terminates, we compute the affine
  * hull of the live iterations (bounded to the original iteration
  * domains) each time we have added extra iterations.
  */
-static void eliminate_dead_code(struct ppcg_scop *ps)
+void eliminate_dead_code(struct ppcg_scop *ps)
 {
   isl_union_set *live;
   isl_union_map *dep;
   isl_union_pw_multi_aff *tagger;
 
   live = isl_union_map_domain(isl_union_map_copy(ps->live_out));
   if (!isl_union_set_is_empty(ps->call)) {
     live = isl_union_set_union(live, isl_union_set_copy(ps->call));
static __isl_give isl_set *set_intersect_str(__isl_take isl_set *set,
 
   ctx = isl_set_get_ctx(set);
   set2 = isl_set_read_from_str(ctx, str);
   set = isl_set_intersect(set, set2);
 
   return set;
 }
 
-static void *ppcg_scop_free(struct ppcg_scop *ps)
+void *ppcg_scop_free(struct ppcg_scop *ps)
 {
   if (!ps)
     return NULL;
 
   isl_set_free(ps->context);
   isl_union_set_free(ps->domain);
   isl_union_set_free(ps->call);
   isl_union_map_free(ps->tagged_reads);
static int check_options(isl_ctx *ctx)
   if (options->ppcg->openmp &&
       !isl_options_get_ast_build_atomic_upper_bound(ctx))
     isl_die(ctx, isl_error_invalid,
       "OpenMP requires atomic bounds", return -1);
 
   return 0;
 }
 
+#if 0
 int main(int argc, char **argv)
 {
   int r;
   isl_ctx *ctx;
   struct options *options;
 
   options = options_new_with_defaults();
   assert(options);
int main(int argc, char **argv)
   else
     r = generate_cpu(ctx, options->ppcg, options->input,
         options->output);
 
   isl_ctx_free(ctx);
 
   return r;
 }
+#endif