Re: [google] Add libgcov interface for accessing profile directory (issue8726046)

[Xinliang David Li <davidxl at google dot com>]

looks ok.

David

On Wed, Apr 17, 2013 at 9:00 AM, Teresa Johnson <tejohnson@google.com> wrote:
> Patch to add interface for querying the profile directory prefix
> specified to the -fprofile-generate= option.
>
> Google ref b/8629045.
>
> Tested with regression tests and internal test. Ok for google branches?
>
> 2013-04-17  Teresa Johnson  <tejohnson@google.com>
>
>         * libgcc/libgcov.c (__gcov_get_profile_prefix): New function.
>         * gcc/tree-profile.c (tree_init_instrumentation): New function.
>         * gcc/coverage.c (get_const_string_type): Make non-static.
>         (coverage_init): Invoke tree_init_instrumentation().
>         * gcc/coverage.h (get_const_string_type): Declare.
>         (tree_init_instrumentation): Ditto.
>
> Index: libgcc/libgcov.c
> ===================================================================
> --- libgcc/libgcov.c    (revision 197640)
> +++ libgcc/libgcov.c    (working copy)
> @@ -183,6 +183,14 @@ unsigned int __gcov_sampling_enabled ()
>    return __gcov_has_sampling;
>  }
>
> +/* Profile directory prefix specified to -fprofile-generate=.  */
> +extern char * __gcov_profile_prefix;
> +
> +char *__gcov_get_profile_prefix ()
> +{
> +  return __gcov_profile_prefix;
> +}
> +
>  /* Per thread sample counter.  */
>  THREAD_PREFIX gcov_unsigned_t __gcov_sample_counter = 0;
>
> Index: gcc/tree-profile.c
> ===================================================================
> --- gcc/tree-profile.c  (revision 197640)
> +++ gcc/tree-profile.c  (working copy)
> @@ -165,6 +165,9 @@ static struct pointer_set_t *instrumentation_to_be
>  /* extern __thread gcov_unsigned_t __gcov_sample_counter  */
>  static GTY(()) tree gcov_sample_counter_decl = NULL_TREE;
>
> +/* extern gcov_unsigned_t __gcov_profile_prefix  */
> +static tree GTY(()) gcov_profile_prefix_decl = NULL_TREE;
> +
>  /* extern gcov_unsigned_t __gcov_sampling_period  */
>  static tree GTY(()) gcov_sampling_period_decl = NULL_TREE;
>
> @@ -407,6 +410,41 @@ cleanup_instrumentation_sampling (void)
>      }
>  }
>
> +/* Initialization function for FDO instrumentation.  */
> +
> +void
> +tree_init_instrumentation (void)
> +{
> +  if (!gcov_profile_prefix_decl)
> +    {
> +      tree prefix_ptr;
> +      int prefix_len;
> +      tree prefix_string;
> +
> +      /* Construct an initializer for __gcov_profile_prefix.  */
> +      gcov_profile_prefix_decl =
> +        build_decl (UNKNOWN_LOCATION, VAR_DECL,
> +                    get_identifier ("__gcov_profile_prefix"),
> +                    get_const_string_type ());
> +      TREE_PUBLIC (gcov_profile_prefix_decl) = 1;
> +      DECL_ARTIFICIAL (gcov_profile_prefix_decl) = 1;
> +      make_decl_one_only (gcov_profile_prefix_decl,
> +                          DECL_ASSEMBLER_NAME (gcov_profile_prefix_decl));
> +      TREE_STATIC (gcov_profile_prefix_decl) = 1;
> +
> +      prefix_len = strlen (profile_data_prefix);
> +      prefix_string = build_string (prefix_len + 1, profile_data_prefix);
> +      TREE_TYPE (prefix_string) = build_array_type
> +          (char_type_node, build_index_type
> +           (build_int_cst (NULL_TREE, prefix_len)));
> +      prefix_ptr = build1 (ADDR_EXPR, get_const_string_type (),
> +                           prefix_string);
> +
> +      DECL_INITIAL (gcov_profile_prefix_decl) = prefix_ptr;
> +      varpool_finalize_decl (gcov_profile_prefix_decl);
> +    }
> +}
> +
>  /* Initialization function for FDO sampling.  */
>
>  void
> Index: gcc/coverage.c
> ===================================================================
> --- gcc/coverage.c      (revision 197640)
> +++ gcc/coverage.c      (working copy)
> @@ -227,7 +227,7 @@ get_gcov_unsigned_t (void)
>
>  /* Return the type node for const char *.  */
>
> -static tree
> +tree
>  get_const_string_type (void)
>  {
>    return build_pointer_type
> @@ -2879,6 +2879,7 @@ coverage_init (const char *filename, const char* s
>    /* Define variables which are referenced at runtime by libgcov.  */
>    if (profiling_enabled_p ())
>      {
> +      tree_init_instrumentation ();
>        tree_init_dyn_ipa_parameters ();
>        init_pmu_profiling ();
>        tree_init_instrumentation_sampling ();
> Index: gcc/coverage.h
> ===================================================================
> --- gcc/coverage.h      (revision 197640)
> +++ gcc/coverage.h      (working copy)
> @@ -82,6 +82,7 @@ extern bool pmu_data_present (void);
>
>  extern tree get_gcov_type (void);
>  extern tree get_gcov_unsigned_t (void);
> +extern tree get_const_string_type (void);
>
>  /* Mark this module as containing asm statements.  */
>  extern void coverage_has_asm_stmt (void);
> @@ -89,5 +90,6 @@ extern void coverage_has_asm_stmt (void);
>  /* Defined in tree-profile.c.  */
>  extern void tree_init_instrumentation_sampling (void);
>  extern void tree_init_dyn_ipa_parameters (void);
> +extern void tree_init_instrumentation (void);
>
>  #endif
>
> --
> This patch is available for review at http://codereview.appspot.com/8726046