gpu.h

   1 #ifndef _GPU_H
   2 #define _GPU_H
   3
   4 #include "ppcg.h"
   5 #include "ppcg_options.h"
   6
   7 struct gpu_array_info {
   8         isl_space *dim;
   9         /* Element type. */
  10         char *type;
  11         /* Element size. */
  12         int size;
  13         /* Name of the array. */
  14         char *name;
  15         /* Number of indices. */
  16         unsigned n_index;
  17         /* For each index, a bound on the array in that direction. */
  18         isl_pw_aff **bound;
  19
  20         /* All references to this array; point to elements of a linked list. */
  21         int n_ref;
  22         struct gpu_stmt_access **refs;
  23
  24         /* The reference groups associated to this array. */
  25         int n_group;
  26         struct gpu_array_ref_group **groups;
  27
  28         /* For scalars, is this scalar read-only within the entire program? */
  29         int read_only;
  30 };
  31
  32 /* For each index i, array->bound[i] specialized to the current kernel. */
  33 struct gpu_local_array_info {
  34         isl_pw_aff_list *bound;
  35 };
  36
  37 struct gpu_prog {
  38         isl_ctx *ctx;
  39
  40         struct ppcg_scop *scop;
  41
  42         /* Set of parameter values */
  43         isl_set *context;
  44
  45         /* All read accesses in the entire program */
  46         isl_union_map *read;
  47
  48         /* All write accesses in the entire program */
  49         isl_union_map *write;
  50
  51         /* Uninitialized data elements (or an overapproximation) */
  52         isl_union_set *copy_in;
  53
  54         /* Array of statements */
  55         int n_stmts;
  56         struct gpu_stmt *stmts;
  57
  58         int n_array;
  59         struct gpu_array_info *array;
  60 };
  61
  62 enum ppcg_kernel_access_type {
  63         ppcg_access_global,
  64         ppcg_access_shared,
  65         ppcg_access_private
  66 };
  67
  68 enum ppcg_kernel_stmt_type {
  69         ppcg_kernel_copy,
  70         ppcg_kernel_domain,
  71         ppcg_kernel_sync
  72 };
  73
  74 /* Instance specific information about an access inside a kernel statement.
  75  *
  76  * type indicates whether it is a global, shared or private access
  77  * array is the original array information and may be NULL in case
  78  *      of an affine expression
  79  * local_array is a pointer to the appropriate element in the "array"
  80  *      array of the ppcg_kernel to which this access belongs.  It is
  81  *      NULL whenever array is NULL.
  82  * local_name is the name of the array or its local copy
  83  * index is the sequence of local index expressions
  84  */
  85 struct ppcg_kernel_access {
  86         enum ppcg_kernel_access_type type;
  87         struct gpu_array_info *array;
  88         struct gpu_local_array_info *local_array;
  89         char *local_name;
  90         isl_ast_expr_list *index;
  91 };
  92
  93 /* Representation of special statements, in particular copy statements
  94  * and __syncthreads statements, inside a kernel.
  95  *
  96  * type represents the kind of statement
  97  *
  98  *
  99  * for ppcg_kernel_copy statements we have
 100  *
 101  * read is set if the statement should copy data from global memory
 102  * to shared memory or registers.
 103  *
 104  * index expresses the array element that needs to be copied as a "call"
 105  * to the array
 106  * local_index expresses the corresponding element in the tile
 107  *
 108  * array refers to the original array being copied
 109  * local_array is a pointer to the appropriate element in the "array"
 110  *      array of the ppcg_kernel to which this copy access belongs
 111  *
 112  *
 113  * for ppcg_kernel_domain statements we have
 114  *
 115  * stmt is the corresponding input statement
 116  *
 117  * n_access is the number of accesses in stmt
 118  * access is an array of local information about the accesses
 119  */
 120 struct ppcg_kernel_stmt {
 121         enum ppcg_kernel_stmt_type type;
 122
 123         union {
 124                 struct {
 125                         int read;
 126                         isl_ast_expr *index;
 127                         isl_ast_expr *local_index;
 128                         struct gpu_array_info *array;
 129                         struct gpu_local_array_info *local_array;
 130                 } c;
 131                 struct {
 132                         struct gpu_stmt *stmt;
 133
 134                         int n_access;
 135                         struct ppcg_kernel_access *access;
 136                 } d;
 137         } u;
 138 };
 139
 140 /* Representation of a local variable in a kernel.
 141  */
 142 struct ppcg_kernel_var {
 143         struct gpu_array_info *array;
 144         enum ppcg_kernel_access_type type;
 145         char *name;
 146         isl_vec *size;
 147 };
 148
 149 /* Representation of a kernel.
 150  *
 151  * id is the sequence number of the kernel.
 152  *
 153  * the first n_block elements of block_dim represent the size of the block.
 154  *
 155  * grid_size reflects the effect grid size.
 156  *
 157  * context is a parametric set containing the values of the parameters
 158  * for which this kernel may be run.
 159  *
 160  * arrays is the set of accessed array elements.
 161  *
 162  * space is the schedule space of the AST context.  That is, it represents
 163  * the loops of the generated host code containing the kernel launch.
 164  *
 165  * n_array is the total number of arrays in the input program and also
 166  * the number of element in the array array.
 167  * array contains information about each array that is local
 168  * to the current kernel.  If an array is not ussed in a kernel,
 169  * then the corresponding entry does not contain any information.
 170  */
 171 struct ppcg_kernel {
 172         int id;
 173
 174         int n_grid;
 175         int grid_dim[2];
 176
 177         int n_block;
 178         int block_dim[3];
 179
 180         isl_multi_pw_aff *grid_size;
 181         isl_set *context;
 182
 183         isl_union_set *arrays;
 184
 185         isl_space *space;
 186
 187         int n_array;
 188         struct gpu_local_array_info *array;
 189
 190         int n_var;
 191         struct ppcg_kernel_var *var;
 192
 193         isl_ast_node *tree;
 194 };
 195
 196 int gpu_array_is_scalar(struct gpu_array_info *array);
 197 int gpu_array_is_read_only_scalar(struct gpu_array_info *array);
 198
 199 struct gpu_prog *gpu_prog_alloc(isl_ctx *ctx, struct ppcg_scop *scop);
 200 void gpu_prog_free(struct gpu_prog *prog);
 201
 202 __isl_give isl_set *add_context_from_str(__isl_take isl_set *set,
 203         const char *str);
 204
 205 __isl_give isl_ast_node *generate_gpu(isl_ctx *ctx, struct gpu_prog *prog,
 206         struct ppcg_options *options);
 207
 208 #endif