[GOLD] ppc64 out-of-line register save/restore functions
Alan Modra
amodra@gmail.com
Wed Sep 2 08:14:00 GMT 2015
[GOLD] ppc64 out-of-line register save/restore functions
Gold version of a4b6fadd. Don't emit long branch or plt branch stubs
to save/restore functions. Copy them instead.
PR 18878
* powerpc.cc (Target_powerpc): Add savres_section_ and accessor.
(Target_powerpc::Branch_info::make_stub): Determine whether long
branch stub is for save/restore function.
(Branch_stub_ent): Add save_res_, and extra parm to constructor.
(Stub_table): Add need_save_res_.
(Stub_table:clear_stubs): Clear need_save_res_.
(Stub_table:set_address_and_size): Add save/restore section size.
(Stub_table::add_long_branch_entry): Add save_res param. Set
need_save_res_, but don't add space for save/restore stubs.
(Stub_table::find_long_branch_entry): Return offset to local copy
of save/restore func.
(Stub_table::do_write): Don't output save/restore stubs. Instead
copy the save/restore functions.
(Output_data_save_res:contents): New accessor.
(Target_powerpc::define_save_restore_funcs): Set savres_section_.
diff --git a/gold/powerpc.cc b/gold/powerpc.cc
index 3311a1d..80f9e33 100644
--- a/gold/powerpc.cc
+++ b/gold/powerpc.cc
@@ -63,6 +63,9 @@ template<int size, bool big_endian>
class Stub_table;
template<int size, bool big_endian>
+class Output_data_save_res;
+
+template<int size, bool big_endian>
class Target_powerpc;
struct Stub_table_owner
@@ -510,7 +513,7 @@ class Target_powerpc : public Sized_target<size, big_endian>
tlsld_got_offset_(-1U),
stub_tables_(), branch_lookup_table_(), branch_info_(),
plt_thread_safe_(false), relax_failed_(false), relax_fail_count_(0),
- stub_group_size_(0)
+ stub_group_size_(0), savres_section_(0)
{
}
@@ -775,6 +778,12 @@ class Target_powerpc : public Sized_target<size, big_endian>
return 24;
}
+ Output_data_save_res<size, big_endian>*
+ savres_section() const
+ {
+ return this->savres_section_;
+ }
+
// Add any special sections for this symbol to the gc work list.
// For powerpc64, this adds the code section of a function
// descriptor.
@@ -1315,6 +1324,8 @@ class Target_powerpc : public Sized_target<size, big_endian>
bool relax_failed_;
int relax_fail_count_;
int32_t stub_group_size_;
+
+ Output_data_save_res<size, big_endian> *savres_section_;
};
template<>
@@ -2740,8 +2751,13 @@ Target_powerpc<size, big_endian>::Branch_info::make_stub(
this->object_->section_name(this->shndx_).c_str());
return true;
}
+ bool save_res = (size == 64
+ && gsym != NULL
+ && gsym->source() == Symbol::IN_OUTPUT_DATA
+ && gsym->output_data() == target->savres_section());
return stub_table->add_long_branch_entry(this->object_,
- this->r_type_, from, to);
+ this->r_type_,
+ from, to, save_res);
}
}
return true;
@@ -3581,7 +3597,8 @@ class Stub_table : public Output_relaxed_input_section
targ_(targ), plt_call_stubs_(), long_branch_stubs_(),
orig_data_size_(owner->current_data_size()),
plt_size_(0), last_plt_size_(0),
- branch_size_(0), last_branch_size_(0), eh_frame_added_(false)
+ branch_size_(0), last_branch_size_(0), eh_frame_added_(false),
+ need_save_res_(false)
{
this->set_output_section(output_section);
@@ -3628,7 +3645,7 @@ class Stub_table : public Output_relaxed_input_section
// Add a long branch stub.
bool
add_long_branch_entry(const Powerpc_relobj<size, big_endian>*,
- unsigned int, Address, Address);
+ unsigned int, Address, Address, bool);
Address
find_long_branch_entry(const Powerpc_relobj<size, big_endian>*,
@@ -3652,6 +3669,7 @@ class Stub_table : public Output_relaxed_input_section
this->plt_size_ = 0;
this->long_branch_stubs_.clear();
this->branch_size_ = 0;
+ this->need_save_res_ = false;
if (all)
{
this->last_plt_size_ = 0;
@@ -3665,6 +3683,8 @@ class Stub_table : public Output_relaxed_input_section
Address start_off = off;
off += this->orig_data_size_;
Address my_size = this->plt_size_ + this->branch_size_;
+ if (this->need_save_res_)
+ my_size += this->targ_->savres_section()->data_size();
if (my_size != 0)
off = align_address(off, this->stub_align());
// Include original section size and alignment padding in size
@@ -3919,8 +3939,9 @@ class Stub_table : public Output_relaxed_input_section
class Branch_stub_ent
{
public:
- Branch_stub_ent(const Powerpc_relobj<size, big_endian>* obj, Address to)
- : dest_(to), toc_base_off_(0)
+ Branch_stub_ent(const Powerpc_relobj<size, big_endian>* obj,
+ Address to, bool save_res)
+ : dest_(to), toc_base_off_(0), save_res_(save_res)
{
if (size == 64)
toc_base_off_ = obj->toc_base_offset();
@@ -3935,6 +3956,7 @@ class Stub_table : public Output_relaxed_input_section
Address dest_;
unsigned int toc_base_off_;
+ bool save_res_;
};
class Branch_stub_ent_hash
@@ -3958,6 +3980,9 @@ class Stub_table : public Output_relaxed_input_section
section_size_type plt_size_, last_plt_size_, branch_size_, last_branch_size_;
// Whether .eh_frame info has been created for this stub section.
bool eh_frame_added_;
+ // Set if this stub group needs a copy of out-of-line register
+ // save/restore functions.
+ bool need_save_res_;
};
// Add a plt call stub, if we do not already have one for this
@@ -4056,21 +4081,27 @@ Stub_table<size, big_endian>::add_long_branch_entry(
const Powerpc_relobj<size, big_endian>* object,
unsigned int r_type,
Address from,
- Address to)
+ Address to,
+ bool save_res)
{
- Branch_stub_ent ent(object, to);
+ Branch_stub_ent ent(object, to, save_res);
Address off = this->branch_size_;
if (this->long_branch_stubs_.insert(std::make_pair(ent, off)).second)
{
- unsigned int stub_size = this->branch_stub_size(to);
- this->branch_size_ = off + stub_size;
- if (size == 64 && stub_size != 4)
- this->targ_->add_branch_lookup_table(to);
+ if (save_res)
+ this->need_save_res_ = true;
+ else
+ {
+ unsigned int stub_size = this->branch_stub_size(to);
+ this->branch_size_ = off + stub_size;
+ if (size == 64 && stub_size != 4)
+ this->targ_->add_branch_lookup_table(to);
+ }
}
return this->can_reach_stub(from, off, r_type);
}
-// Find long branch stub.
+// Find long branch stub offset.
template<int size, bool big_endian>
typename Stub_table<size, big_endian>::Address
@@ -4078,10 +4109,14 @@ Stub_table<size, big_endian>::find_long_branch_entry(
const Powerpc_relobj<size, big_endian>* object,
Address to) const
{
- Branch_stub_ent ent(object, to);
+ Branch_stub_ent ent(object, to, false);
typename Branch_stub_entries::const_iterator p
= this->long_branch_stubs_.find(ent);
- return p == this->long_branch_stubs_.end() ? invalid_address : p->second;
+ if (p == this->long_branch_stubs_.end())
+ return invalid_address;
+ if (p->first.save_res_)
+ return to - this->targ_->savres_section()->address() + this->branch_size_;
+ return p->second;
}
// A class to handle .glink.
@@ -4420,6 +4455,8 @@ Stub_table<size, big_endian>::do_write(Output_file* of)
bs != this->long_branch_stubs_.end();
++bs)
{
+ if (bs->first.save_res_)
+ continue;
p = oview + this->plt_size_ + bs->second;
Address loc = this->stub_address() + this->plt_size_ + bs->second;
Address delta = bs->first.dest_ - loc;
@@ -4531,6 +4568,8 @@ Stub_table<size, big_endian>::do_write(Output_file* of)
bs != this->long_branch_stubs_.end();
++bs)
{
+ if (bs->first.save_res_)
+ continue;
p = oview + this->plt_size_ + bs->second;
Address loc = this->stub_address() + this->plt_size_ + bs->second;
Address delta = bs->first.dest_ - loc;
@@ -4557,6 +4596,12 @@ Stub_table<size, big_endian>::do_write(Output_file* of)
}
}
}
+ if (this->need_save_res_)
+ {
+ p = oview + this->plt_size_ + this->branch_size_;
+ memcpy (p, this->targ_->savres_section()->contents(),
+ this->targ_->savres_section()->data_size());
+ }
}
// Write out .glink.
@@ -4767,6 +4812,12 @@ class Output_data_save_res : public Output_section_data_build
public:
Output_data_save_res(Symbol_table* symtab);
+ const unsigned char*
+ contents() const
+ {
+ return contents_;
+ }
+
protected:
// Write to a map file.
void
@@ -6685,8 +6736,9 @@ Target_powerpc<size, big_endian>::define_save_restore_funcs(
{
if (size == 64)
{
- Output_data_save_res<64, big_endian>* savres
- = new Output_data_save_res<64, big_endian>(symtab);
+ Output_data_save_res<size, big_endian>* savres
+ = new Output_data_save_res<size, big_endian>(symtab);
+ this->savres_section_ = savres;
layout->add_output_section_data(".text", elfcpp::SHT_PROGBITS,
elfcpp::SHF_ALLOC | elfcpp::SHF_EXECINSTR,
savres, ORDER_TEXT, false);
--
Alan Modra
Australia Development Lab, IBM
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