From 55a2bb35466651972b102f5f8b5ec53a17be5b55 Mon Sep 17 00:00:00 2001 From: Sriraman Tallam Date: Mon, 4 Jan 2010 19:08:39 +0000 Subject: * gc.h (gc_process_relocs): Call is_section_foldable_candidate to check for .text or .gnu.linkonce.t sections. * icf.cc (Icf::find_identical_sections): Ditto. Change the detection for mangled function name within the section name. * icf.h (is_section_foldable_candidate): New function. --- gold/icf.cc | 21 ++++++++++++--------- 1 file changed, 12 insertions(+), 9 deletions(-) (limited to 'gold/icf.cc') diff --git a/gold/icf.cc b/gold/icf.cc index 03b927a..48cb9bf 100644 --- a/gold/icf.cc +++ b/gold/icf.cc @@ -1,6 +1,6 @@ // icf.cc -- Identical Code Folding. // -// Copyright 2009 Free Software Foundation, Inc. +// Copyright 2009, 2010 Free Software Foundation, Inc. // Written by Sriraman Tallam . // This file is part of gold. @@ -23,7 +23,7 @@ // Identical Code Folding Algorithm // ---------------------------------- // Detecting identical functions is done here and the basic algorithm -// is as follows. A checksum is computed on each .text section using +// is as follows. A checksum is computed on each foldable section using // its contents and relocations. If the symbol name corresponding to // a relocation is known it is used to compute the checksum. If the // symbol name is not known the stringified name of the object and the @@ -34,8 +34,8 @@ // checking the contents when two sections have the same checksum. // // However, two functions A and B with identical text but with -// relocations pointing to different .text sections can be identical if -// the corresponding .text sections to which their relocations point to +// relocations pointing to different foldable sections can be identical if +// the corresponding foldable sections to which their relocations point to // turn out to be identical. Hence, this checksumming process must be // done repeatedly until convergence is obtained. Here is an example for // the following case : @@ -102,7 +102,7 @@ // behaviour. // // -// How to run : --icf +// How to run : --icf=[safe|all|none] // Optional parameters : --icf-iterations --print-icf-sections // // Performance : Less than 20 % link-time overhead on industry strength @@ -570,17 +570,20 @@ Icf::find_identical_sections(const Input_objects* input_objects, for (unsigned int i = 0;i < (*p)->shnum(); ++i) { const char* section_name = (*p)->section_name(i).c_str(); - // Only looking to fold functions, so just look at .text sections. - if (!is_prefix_of(".text.", section_name)) + if (!is_section_foldable_candidate(section_name)) continue; if (!(*p)->is_section_included(i)) continue; if (parameters->options().gc_sections() && symtab->gc()->is_section_garbage(*p, i)) continue; - // With --icf=safe, check if mangled name is a ctor or a dtor. + // With --icf=safe, check if the mangled function name is a ctor + // or a dtor. The mangled function name can be obtained from the + // section name by stripping the section prefix. + const char* mangled_func_name = strrchr(section_name, '.'); + gold_assert(mangled_func_name != NULL); if (parameters->options().icf_safe_folding() - && !is_function_ctor_or_dtor(section_name + 6)) + && !is_function_ctor_or_dtor(mangled_func_name + 1)) continue; this->id_section_.push_back(Section_id(*p, i)); this->section_id_[Section_id(*p, i)] = section_num; -- cgit v1.1