Import isl(+imath) as an external library into Polly

With this patch Polly is always GPL-free (no dependency on GMP any more). As a
result, building and distributing Polly will be easier. Furthermore, there is no
need to tightly coordinate isl and Polly releases anymore.

We import isl b3e0fa7a05d as well as imath 4d707e5ef2. These are the git
versions Polly currently was tested with when using utils/checkout_isl.sh. The
imported libraries are both MIT-style licensed.

We build isl and imath with -fvisibility=hidden to avoid clashes in case other
projects (such as gcc) use conflicting versions of isl. The use of imath can
temporarily reduce compile-time performance of Polly. We will work on
performance tuning in tree.

Patches to isl should be contributed first to the main isl repository and can
then later be reimported to Polly.

This patch is also a prerequisite for the upcoming isl C++ interface.

llvm-svn: 228193

1 files changed, 138 insertions, 0 deletions

diff --git a/polly/lib/External/isl/codegen.c b/polly/lib/External/isl/codegen.c
new file mode 100644
index 00000000000..e9cd692fe8d
--- /dev/null
+++ b/polly/lib/External/isl/codegen.c
@@ -0,0 +1,138 @@
+/*
+ * Copyright 2012      Ecole Normale Superieure
+ *
+ * Use of this software is governed by the MIT license
+ *
+ * Written by Sven Verdoolaege,
+ * Ecole Normale Superieure, 45 rue d’Ulm, 75230 Paris, France
+ */
+
+/* This program prints an AST that scans the domain elements of
+ * the domain of a given schedule in the order of their image(s).
+ *
+ * The input consists of three sets/relations.
+ * - a schedule
+ * - a context
+ * - a relation describing AST generation options
+ */
+
+#include <assert.h>
+#include <isl/ast.h>
+#include <isl/ast_build.h>
+#include <isl/options.h>
+#include <isl/set.h>
+
+struct options {
+	struct isl_options	*isl;
+	unsigned		 atomic;
+	unsigned		 separate;
+};
+
+ISL_ARGS_START(struct options, options_args)
+ISL_ARG_CHILD(struct options, isl, "isl", &isl_options_args, "isl options")
+ISL_ARG_BOOL(struct options, atomic, 0, "atomic", 0,
+	"globally set the atomic option")
+ISL_ARG_BOOL(struct options, separate, 0, "separate", 0,
+	"globally set the separate option")
+ISL_ARGS_END
+
+ISL_ARG_DEF(options, struct options, options_args)
+
+/* Return a universal, 1-dimensional set with the given name.
+ */
+static __isl_give isl_union_set *universe(isl_ctx *ctx, const char *name)
+{
+	isl_space *space;
+
+	space = isl_space_set_alloc(ctx, 0, 1);
+	space = isl_space_set_tuple_name(space, isl_dim_set, name);
+	return isl_union_set_from_set(isl_set_universe(space));
+}
+
+/* Set the "name" option for the entire schedule domain.
+ */
+static __isl_give isl_union_map *set_universe(__isl_take isl_union_map *opt,
+	__isl_keep isl_union_map *schedule, const char *name)
+{
+	isl_ctx *ctx;
+	isl_union_set *domain, *target;
+	isl_union_map *option;
+
+	ctx = isl_union_map_get_ctx(opt);
+
+	domain = isl_union_map_range(isl_union_map_copy(schedule));
+	domain = isl_union_set_universe(domain);
+	target = universe(ctx, name);
+	option = isl_union_map_from_domain_and_range(domain, target);
+	opt = isl_union_map_union(opt, option);
+
+	return opt;
+}
+
+/* Update the build options based on the user-specified options.
+ *
+ * If the --separate or --atomic options were specified, then
+ * we clear any separate or atomic options that may already exist in "opt".
+ */
+static __isl_give isl_ast_build *set_options(__isl_take isl_ast_build *build,
+	__isl_take isl_union_map *opt, struct options *options,
+	__isl_keep isl_union_map *schedule)
+{
+	if (options->separate || options->atomic) {
+		isl_ctx *ctx;
+		isl_union_set *target;
+
+		ctx = isl_union_map_get_ctx(schedule);
+
+		target = universe(ctx, "separate");
+		opt = isl_union_map_subtract_range(opt, target);
+		target = universe(ctx, "atomic");
+		opt = isl_union_map_subtract_range(opt, target);
+	}
+
+	if (options->separate)
+		opt = set_universe(opt, schedule, "separate");
+	if (options->atomic)
+		opt = set_universe(opt, schedule, "atomic");
+
+	build = isl_ast_build_set_options(build, opt);
+
+	return build;
+}
+
+int main(int argc, char **argv)
+{
+	isl_ctx *ctx;
+	isl_set *context;
+	isl_union_map *schedule;
+	isl_union_map *options_map;
+	isl_ast_build *build;
+	isl_ast_node *tree;
+	struct options *options;
+	isl_printer *p;
+
+	options = options_new_with_defaults();
+	assert(options);
+	argc = options_parse(options, argc, argv, ISL_ARG_ALL);
+
+	ctx = isl_ctx_alloc_with_options(&options_args, options);
+
+	schedule = isl_union_map_read_from_file(ctx, stdin);
+	context = isl_set_read_from_file(ctx, stdin);
+	options_map = isl_union_map_read_from_file(ctx, stdin);
+
+	build = isl_ast_build_from_context(context);
+	build = set_options(build, options_map, options, schedule);
+	tree = isl_ast_build_ast_from_schedule(build, schedule);
+	isl_ast_build_free(build);
+
+	p = isl_printer_to_file(ctx, stdout);
+	p = isl_printer_set_output_format(p, ISL_FORMAT_C);
+	p = isl_printer_print_ast_node(p, tree);
+	isl_printer_free(p);
+
+	isl_ast_node_free(tree);
+
+	isl_ctx_free(ctx);
+	return 0;
+}