// target.h -- target support for gold -*- C++ -*-
-// Copyright 2006, 2007, 2008, 2009 Free Software Foundation, Inc.
+// Copyright 2006, 2007, 2008, 2009, 2010 Free Software Foundation, Inc.
// Written by Ian Lance Taylor <iant@google.com>.
// This file is part of gold.
template<int size>
class Sized_symbol;
class Symbol_table;
+class Output_data;
class Output_section;
class Input_objects;
+class Task;
// The abstract class for target specific handling.
virtual ~Target()
{ }
+ // Virtual function which is set to return true by a target if
+ // it can use relocation types to determine if a function's
+ // pointer is taken.
+ virtual bool
+ can_check_for_function_pointers() const
+ { return false; }
+
+ // This function is used in ICF (icf.cc). This is set to true by
+ // the target if a relocation to a merged section can be processed
+ // to retrieve the contents of the merged section.
+ virtual bool
+ can_icf_inline_merge_sections () const
+ { return false; }
+
+ // Whether a section called SECTION_NAME may have function pointers to
+ // sections not eligible for safe ICF folding.
+ virtual bool
+ section_may_have_icf_unsafe_pointers(const char* section_name) const
+ {
+ // We recognize sections for normal vtables, construction vtables and
+ // EH frames.
+ return (!is_prefix_of(".rodata._ZTV", section_name)
+ && !is_prefix_of(".data.rel.ro._ZTV", section_name)
+ && !is_prefix_of(".rodata._ZTC", section_name)
+ && !is_prefix_of(".data.rel.ro._ZTC", section_name)
+ && !is_prefix_of(".eh_frame", section_name));
+ }
+
// Return the bit size that this target implements. This should
// return 32 or 64.
int
is_local_label_name(const char* name) const
{ return this->do_is_local_label_name(name); }
+ // Get the symbol index to use for a target specific reloc.
+ unsigned int
+ reloc_symbol_index(void* arg, unsigned int type) const
+ { return this->do_reloc_symbol_index(arg, type); }
+
+ // Get the addend to use for a target specific reloc.
+ uint64_t
+ reloc_addend(void* arg, unsigned int type, uint64_t addend) const
+ { return this->do_reloc_addend(arg, type, addend); }
+
+ // Return the PLT section to use for a global symbol. This is used
+ // for STT_GNU_IFUNC symbols.
+ Output_data*
+ plt_section_for_global(const Symbol* sym) const
+ { return this->do_plt_section_for_global(sym); }
+
+ // Return the PLT section to use for a local symbol. This is used
+ // for STT_GNU_IFUNC symbols.
+ Output_data*
+ plt_section_for_local(const Relobj* object, unsigned int symndx) const
+ { return this->do_plt_section_for_local(object, symndx); }
+
+ // Return true if a reference to SYM from a reloc of type R_TYPE
+ // means that the current function may call an object compiled
+ // without -fsplit-stack. SYM is known to be defined in an object
+ // compiled without -fsplit-stack.
+ bool
+ is_call_to_non_split(const Symbol* sym, unsigned int r_type) const
+ { return this->do_is_call_to_non_split(sym, r_type); }
+
// A function starts at OFFSET in section SHNDX in OBJECT. That
// function was compiled with -fsplit-stack, but it refers to a
// function which was compiled without -fsplit-stack. VIEW is a
// Perform a relaxation pass. Return true if layout may be changed.
bool
relax(int pass, const Input_objects* input_objects, Symbol_table* symtab,
- Layout* layout)
+ Layout* layout, const Task* task)
{
// Run the dummy relaxation pass twice if relaxation debugging is enabled.
if (is_debugging_enabled(DEBUG_RELAXATION))
return pass < 2;
- return this->do_relax(pass, input_objects, symtab, layout);
+ return this->do_relax(pass, input_objects, symtab, layout, task);
}
// Return the target-specific name of attributes section. This is
attributes_order(int num) const
{ return this->do_attributes_order(num); }
+ // When a target is selected as the default target, we call this method,
+ // which may be used for expensive, target-specific initialization.
+ void
+ select_as_default_target()
+ { this->do_select_as_default_target(); }
+
protected:
// This struct holds the constant information for a child class. We
// use a struct to avoid the overhead of virtual function calls for
do_adjust_elf_header(unsigned char*, int) const
{ }
- // Virtual function which may be overriden by the child class.
+ // Virtual function which may be overridden by the child class.
virtual bool
do_is_local_label_name(const char*) const;
+ // Virtual function that must be overridden by a target which uses
+ // target specific relocations.
+ virtual unsigned int
+ do_reloc_symbol_index(void*, unsigned int) const
+ { gold_unreachable(); }
+
+ // Virtual function that must be overridden by a target which uses
+ // target specific relocations.
+ virtual uint64_t
+ do_reloc_addend(void*, unsigned int, uint64_t) const
+ { gold_unreachable(); }
+
+ // Virtual functions that must be overridden by a target that uses
+ // STT_GNU_IFUNC symbols.
+ virtual Output_data*
+ do_plt_section_for_global(const Symbol*) const
+ { gold_unreachable(); }
+
+ virtual Output_data*
+ do_plt_section_for_local(const Relobj*, unsigned int) const
+ { gold_unreachable(); }
+
+ // Virtual function which may be overridden by the child class. The
+ // default implementation is that any function not defined by the
+ // ABI is a call to a non-split function.
+ virtual bool
+ do_is_call_to_non_split(const Symbol* sym, unsigned int) const;
+
// Virtual function which may be overridden by the child class.
virtual void
do_calls_non_split(Relobj* object, unsigned int, section_offset_type,
std::string*, std::string*) const;
// make_elf_object hooks. There are four versions of these for
- // different address sizes and endianities.
+ // different address sizes and endianness.
// Set processor specific flags.
void
}
#ifdef HAVE_TARGET_32_LITTLE
- // Virtual functions which may be overriden by the child class.
+ // Virtual functions which may be overridden by the child class.
virtual Object*
do_make_elf_object(const std::string&, Input_file*, off_t,
const elfcpp::Ehdr<32, false>&);
#endif
#ifdef HAVE_TARGET_32_BIG
- // Virtual functions which may be overriden by the child class.
+ // Virtual functions which may be overridden by the child class.
virtual Object*
do_make_elf_object(const std::string&, Input_file*, off_t,
const elfcpp::Ehdr<32, true>&);
#endif
#ifdef HAVE_TARGET_64_LITTLE
- // Virtual functions which may be overriden by the child class.
+ // Virtual functions which may be overridden by the child class.
virtual Object*
do_make_elf_object(const std::string&, Input_file*, off_t,
const elfcpp::Ehdr<64, false>& ehdr);
#endif
#ifdef HAVE_TARGET_64_BIG
- // Virtual functions which may be overriden by the child class.
+ // Virtual functions which may be overridden by the child class.
virtual Object*
do_make_elf_object(const std::string& name, Input_file* input_file,
off_t offset, const elfcpp::Ehdr<64, true>& ehdr);
#endif
- // Virtual functions which may be overriden by the child class.
+ // Virtual functions which may be overridden by the child class.
virtual Output_section*
do_make_output_section(const char* name, elfcpp::Elf_Word type,
elfcpp::Elf_Xword flags);
- // Virtual function which may be overriden by the child class.
+ // Virtual function which may be overridden by the child class.
virtual bool
do_may_relax() const
{ return parameters->options().relax(); }
- // Virtual function which may be overriden by the child class.
+ // Virtual function which may be overridden by the child class.
virtual bool
- do_relax(int, const Input_objects*, Symbol_table*, Layout*)
+ do_relax(int, const Input_objects*, Symbol_table*, Layout*, const Task*)
{ return false; }
// A function for targets to call. Return whether BYTES/LEN matches
set_view_to_nop(unsigned char* view, section_size_type view_size,
section_offset_type offset, size_t len) const;
- // This must be overriden by the child class if it has target-specific
+ // This must be overridden by the child class if it has target-specific
// attributes subsection in the attribute section.
virtual int
do_attribute_arg_type(int) const
do_attributes_order(int num) const
{ return num; }
+ // This may be overridden by the child class.
+ virtual void
+ do_select_as_default_target()
+ { }
+
private:
// The implementations of the four do_make_elf_object virtual functions are
- // almost identical except for their sizes and endianity. We use a template.
+ // almost identical except for their sizes and endianness. We use a template.
// for their implementations.
template<int size, bool big_endian>
inline Object*
section_size_type view_size,
unsigned char* reloc_view,
section_size_type reloc_view_size) = 0;
+
+ // Perform target-specific processing in a relocatable link. This is
+ // only used if we use the relocation strategy RELOC_SPECIAL.
+ // RELINFO points to a Relocation_info structure. SH_TYPE is the relocation
+ // section type. PRELOC_IN points to the original relocation. RELNUM is
+ // the index number of the relocation in the relocation section.
+ // OUTPUT_SECTION is the output section to which the relocation is applied.
+ // OFFSET_IN_OUTPUT_SECTION is the offset of the relocation input section
+ // within the output section. VIEW points to the output view of the
+ // output section. VIEW_ADDRESS is output address of the view. VIEW_SIZE
+ // is the size of the output view and PRELOC_OUT points to the new
+ // relocation in the output object.
+ //
+ // A target only needs to override this if the generic code in
+ // target-reloc.h cannot handle some relocation types.
+
+ virtual void
+ relocate_special_relocatable(const Relocate_info<size, big_endian>*
+ /*relinfo */,
+ unsigned int /* sh_type */,
+ const unsigned char* /* preloc_in */,
+ size_t /* relnum */,
+ Output_section* /* output_section */,
+ off_t /* offset_in_output_section */,
+ unsigned char* /* view */,
+ typename elfcpp::Elf_types<size>::Elf_Addr
+ /* view_address */,
+ section_size_type /* view_size */,
+ unsigned char* /* preloc_out*/)
+ { gold_unreachable(); }
+
+ // Return the number of entries in the GOT. This is only used for
+ // laying out the incremental link info sections. A target needs
+ // to implement this to support incremental linking.
+
+ virtual unsigned int
+ got_entry_count() const
+ { gold_unreachable(); }
+
+ // Return the number of entries in the PLT. This is only used for
+ // laying out the incremental link info sections. A target needs
+ // to implement this to support incremental linking.
+
+ virtual unsigned int
+ plt_entry_count() const
+ { gold_unreachable(); }
+
+ // Return the offset of the first non-reserved PLT entry. This is
+ // only used for laying out the incremental link info sections.
+ // A target needs to implement this to support incremental linking.
+
+ virtual unsigned int
+ first_plt_entry_offset() const
+ { gold_unreachable(); }
+
+ // Return the size of each PLT entry. This is only used for
+ // laying out the incremental link info sections. A target needs
+ // to implement this to support incremental linking.
+
+ virtual unsigned int
+ plt_entry_size() const
+ { gold_unreachable(); }
protected:
Sized_target(const Target::Target_info* pti)