[OpenMP] libomp: fix ittnotify usage.

Replaced storing of ittnotify domain array index into
location info structure (which is now read-only) with storing of
(location info address + ittnotify domain + team size) into hash map.
Replaced __kmp_itt_barrier_domains and __kmp_itt_imbalance_domains arrays with
__kmp_itt_barrier_domains hash map; __kmp_itt_region_domains and
__kmp_itt_region_team_size arrays with __kmp_itt_region_domains hash map.
Basic functionality did not change (at least tried to not change).

The patch fixes https://bugs.llvm.org/show_bug.cgi?id=48644.

Differential Revision: https://reviews.llvm.org/D111580

openmp/runtime/src/kmp_itt.cpp

@@ -24,12 +24,9 @@
 #include "ittnotify_config.h"
 __itt_global __kmp_ittapi_clean_global;
 extern __itt_global __kmp_itt__ittapi_global;
-kmp_int32 __kmp_barrier_domain_count;
-kmp_int32 __kmp_region_domain_count;
-__itt_domain *__kmp_itt_barrier_domains[KMP_MAX_FRAME_DOMAINS];
-__itt_domain *__kmp_itt_region_domains[KMP_MAX_FRAME_DOMAINS];
-__itt_domain *__kmp_itt_imbalance_domains[KMP_MAX_FRAME_DOMAINS];
-kmp_int32 __kmp_itt_region_team_size[KMP_MAX_FRAME_DOMAINS];
+
+kmp_itthash_t __kmp_itt_barrier_domains = {{0}, 0};
+kmp_itthash_t __kmp_itt_region_domains = {{0}, 0};
 __itt_domain *metadata_domain = NULL;
 __itt_string_handle *string_handle_imbl = NULL;
 __itt_string_handle *string_handle_loop = NULL;

openmp/runtime/src/kmp_itt.h

@@ -278,15 +278,21 @@ __kmp_inline void __kmp_itt_stack_callee_leave(__itt_caller);
     } /* if */                                                                 \
   } while (0)
 
-const int KMP_MAX_FRAME_DOMAINS =
-    512; // Maximum number of frame domains to use (maps to
+// Maximum number of frame domains to use (maps to
 // different OpenMP regions in the user source code).
-extern kmp_int32 __kmp_barrier_domain_count;
-extern kmp_int32 __kmp_region_domain_count;
-extern __itt_domain *__kmp_itt_barrier_domains[KMP_MAX_FRAME_DOMAINS];
-extern __itt_domain *__kmp_itt_region_domains[KMP_MAX_FRAME_DOMAINS];
-extern __itt_domain *__kmp_itt_imbalance_domains[KMP_MAX_FRAME_DOMAINS];
-extern kmp_int32 __kmp_itt_region_team_size[KMP_MAX_FRAME_DOMAINS];
+const int KMP_MAX_FRAME_DOMAINS = 997;
+typedef struct kmp_itthash_entry {
+  ident_t *loc;
+  int team_size;
+  __itt_domain *d;
+  struct kmp_itthash_entry *next_in_bucket;
+} kmp_itthash_entry_t;
+typedef struct kmp_itthash {
+  kmp_itthash_entry_t *buckets[KMP_MAX_FRAME_DOMAINS];
+  int count; // just a heuristic to limit number of entries
+} kmp_itthash_t;
+extern kmp_itthash_t __kmp_itt_region_domains;
+extern kmp_itthash_t __kmp_itt_barrier_domains;
 extern __itt_domain *metadata_domain;
 extern __itt_string_handle *string_handle_imbl;
 extern __itt_string_handle *string_handle_loop;