Ok (please add a short comment on the decl_lineno which encodes
discriminator in it).
David
On Wed, Oct 9, 2013 at 4:57 PM, Dehao Chen <de...@google.com> wrote:
> In legacy AutoFDO, callsite is represented as a (lineno, callee_name)
> pair because there could be multiple calls in one line. However, as we
> enhanced the debug info by assigning discriminators for each function
> call in the same line, callee_name is not needed when indexing the
> callsite.
>
> This patch will improve AutoFDO performance because some functions
> have alias (e.g. constructors/destructors), which could make the
> function name matching fail.
>
> Bootstrapped and passed regression test.
>
> OK for google-4_8 branch.
> Dehao
>
> Index: gcc/auto-profile.c
> ===================================================================
> --- gcc/auto-profile.c (revision 203331)
> +++ gcc/auto-profile.c (working copy)
> @@ -174,10 +174,8 @@ class function_instance {
> const function_instance *get_function_instance_by_decl (unsigned lineno,
> tree decl) const;
>
> - /* Callsite, represented as (decl_lineno, callee_function_name_index). */
> - typedef std::pair<unsigned, unsigned> callsite;
> - /* Map from callsite to callee function_instance. */
> - typedef std::map<callsite, const function_instance *> callsite_map;
> + /* Map from callsite decl_lineno to callee function_instance. */
> + typedef std::map<unsigned, const function_instance *> callsite_map;
> /* Map from source location (decl_lineno) to profile (count_info). */
> typedef std::map<unsigned, count_info> position_count_map;
>
> @@ -430,8 +428,7 @@ const function_instance *function_instance::get_fu
> int func_name_idx = afdo_function_name_map->get_index_by_decl (decl);
> if (func_name_idx != -1)
> {
> - callsite_map::const_iterator ret = callsites.find (
> - std::make_pair (lineno, func_name_idx));
> + callsite_map::const_iterator ret = callsites.find (lineno);
> if (ret != callsites.end ())
> return ret->second;
> }
> @@ -439,8 +436,7 @@ const function_instance *function_instance::get_fu
> lang_hooks.dwarf_name (decl, 0));
> if (func_name_idx != -1)
> {
> - callsite_map::const_iterator ret = callsites.find (
> - std::make_pair (lineno, func_name_idx));
> + callsite_map::const_iterator ret = callsites.find (lineno);
> if (ret != callsites.end ())
> return ret->second;
> }
> @@ -500,10 +496,7 @@ const function_instance *function_instance::read_f
> }
> for (unsigned i = 0; i < num_callsites; i++) {
> unsigned offset = gcov_read_unsigned ();
> - const function_instance *callee_function_instance =
> - read_function_instance (stack, 0);
> - s->callsites[std::make_pair (offset, callee_function_instance->name ())]
> =
> - callee_function_instance;
> + s->callsites[offset] = read_function_instance (stack, 0);
> }
> stack->pop_back();
> return s;
