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Diffstat (limited to 'polly/lib/External/ppcg/opencl.c')
| -rw-r--r-- | polly/lib/External/ppcg/opencl.c | 1290 |
1 files changed, 1290 insertions, 0 deletions
diff --git a/polly/lib/External/ppcg/opencl.c b/polly/lib/External/ppcg/opencl.c new file mode 100644 index 00000000000..c61382f2066 --- /dev/null +++ b/polly/lib/External/ppcg/opencl.c @@ -0,0 +1,1290 @@ +/* + * 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); + + p = isl_ast_op_type_print_macro(isl_ast_op_max, 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; + + 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, "); + + need_lower_bound = !is_array_positive_size_guard_trivial(array); + if (need_lower_bound) { + p = isl_printer_print_str(p, "max(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; +} + +/* 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; +} + +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 = isl_ast_op_type_print_macro(isl_ast_op_fdiv_q, p); + p = ppcg_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_pw_aff *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)) { + bound_grid = isl_multi_pw_aff_get_pw_aff(kernel->grid_size, i); + p = isl_printer_print_str(p, "("); + p = isl_printer_print_pw_aff(p, bound_grid); + p = isl_printer_print_str(p, ") * "); + p = isl_printer_print_int(p, kernel->block_dim[i]); + isl_pw_aff_free(bound_grid); + } else if (i >= grid_dim) + p = isl_printer_print_int(p, kernel->block_dim[i]); + else { + bound_grid = isl_multi_pw_aff_get_pw_aff(kernel->grid_size, i); + p = isl_printer_print_pw_aff(p, bound_grid); + isl_pw_aff_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 a statement for copying an array to or from the device. + * The statement identifier 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. + * + * Extract the array from the identifier and call + * copy_array_to_device or copy_array_from_device. + */ +static __isl_give isl_printer *print_to_from_device(__isl_take isl_printer *p, + __isl_keep isl_ast_node *node, struct gpu_prog *prog) +{ + 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) + array = NULL; + 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 and + * statements that copy data to/from the device. + * The original user statements and the kernel launches have + * an associated annotation, while the data copy statements do not. + * The latter are handled by print_to_from_device. + * 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_to_from_device(p, node, data->prog); + + 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 = ppcg_print_macros(p, tree); + p = isl_ast_node_print(tree, p, print_options); + + 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; +} + +/* 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; +} + +/* 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 = ppcg_start_block(p); + + 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); + + p = opencl_print_host_code(p, prog, tree, opencl); + + p = opencl_release_device_arrays(p, prog); + p = opencl_release_cl_objects(p, opencl); + + p = ppcg_end_block(p); + + 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; +} |
