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-rw-r--r--gold/ChangeLog26
-rw-r--r--gold/arm.cc276
2 files changed, 296 insertions, 6 deletions
diff --git a/gold/ChangeLog b/gold/ChangeLog
index 2bf56d4..0752d08 100644
--- a/gold/ChangeLog
+++ b/gold/ChangeLog
@@ -1,3 +1,29 @@
+2010-01-20 Viktor Kutuzov <vkutuzov@accesssoftek.com>
+
+ * gold/arm.cc: Added support for R_ARM_V4BX relocation
+ (class Arm_v4bx_stub): New class.
+ (DEF_STUBS): Updated definition to support v4_veneer_bx.
+ (Stub_factory::make_arm_v4bx_stub): New method.
+ (Stub_factory::elf32_arm_stub_v4_veneer_bx): New veneer template.
+ (Stub_table::empty): Handle v4bx stubs.
+ (Stub_table::add_arm_v4bx_stub): New method.
+ (Stub_table::find_arm_v4bx_stub): New method.
+ (Arm_relocate_functions::v4bx): New method.
+ (Target_arm::fix_v4bx): New method.
+ (Target_arm::Target_arm): Handle R_ARM_V4BX.
+ (Stub_table::relocate_stubs): Likewise.
+ (Stub_table::do_write): Likewise.
+ (Stub_table::update_data_size_and_addralign): Likewise.
+ (Stub_table::finalize_stubs): Likewise.
+ (Target_arm::Scan::local): Likewise.
+ (Target_arm::Scan::global): Likewise.
+ (Target_arm::do_finalize_sections): Likewise.
+ (Target_arm::Relocate::relocate): Likewise.
+ (Target_arm::Relocatable_size_for_reloc::get_size_for_reloc):
+ Likewise.
+ (Target_arm::scan_reloc_for_stub): Likewise.
+ (Target_arm::scan_reloc_section_for_stubs): Likewise.
+
2010-01-19 Ian Lance Taylor <iant@google.com>
* output.cc (Output_section_headers::do_sized_write): Write large
diff --git a/gold/arm.cc b/gold/arm.cc
index 1ab909e..87459a5 100644
--- a/gold/arm.cc
+++ b/gold/arm.cc
@@ -122,6 +122,7 @@ const int32_t THM2_MAX_BWD_BRANCH_OFFSET = (-(1 << 24) + 4);
// R_ARM_MOVT_PREL
// R_ARM_THM_MOVW_PREL_NC
// R_ARM_THM_MOVT_PREL
+// R_ARM_V4BX
// R_ARM_THM_JUMP6
// R_ARM_THM_JUMP8
// R_ARM_THM_JUMP11
@@ -254,7 +255,8 @@ class Insn_template
DEF_STUB(a8_veneer_b_cond) \
DEF_STUB(a8_veneer_b) \
DEF_STUB(a8_veneer_bl) \
- DEF_STUB(a8_veneer_blx)
+ DEF_STUB(a8_veneer_blx) \
+ DEF_STUB(v4_veneer_bx)
// Stub types.
@@ -275,7 +277,7 @@ typedef enum
arm_stub_cortex_a8_last = arm_stub_a8_veneer_blx,
// Last stub type.
- arm_stub_type_last = arm_stub_a8_veneer_blx
+ arm_stub_type_last = arm_stub_v4_veneer_bx
} Stub_type;
#undef DEF_STUB
@@ -748,6 +750,64 @@ class Cortex_a8_stub : public Stub
uint32_t original_insn_;
};
+// ARMv4 BX Rx branch relocation stub class.
+class Arm_v4bx_stub : public Stub
+{
+ public:
+ ~Arm_v4bx_stub()
+ { }
+
+ // Return the associated register.
+ uint32_t
+ reg() const
+ { return this->reg_; }
+
+ protected:
+ // Arm V4BX stubs are created via a stub factory. So these are protected.
+ Arm_v4bx_stub(const Stub_template* stub_template, const uint32_t reg)
+ : Stub(stub_template), reg_(reg)
+ { }
+
+ friend class Stub_factory;
+
+ // Return the relocation target address of the i-th relocation in the
+ // stub.
+ Arm_address
+ do_reloc_target(size_t)
+ { gold_unreachable(); }
+
+ // This may be overridden in the child class.
+ virtual void
+ do_write(unsigned char* view, section_size_type view_size, bool big_endian)
+ {
+ if (big_endian)
+ this->do_fixed_endian_v4bx_write<true>(view, view_size);
+ else
+ this->do_fixed_endian_v4bx_write<false>(view, view_size);
+ }
+
+ private:
+ // A template to implement do_write.
+ template<bool big_endian>
+ void inline
+ do_fixed_endian_v4bx_write(unsigned char* view, section_size_type)
+ {
+ const Insn_template* insns = this->stub_template()->insns();
+ elfcpp::Swap<32, big_endian>::writeval(view,
+ (insns[0].data()
+ + (this->reg_ << 16)));
+ view += insns[0].size();
+ elfcpp::Swap<32, big_endian>::writeval(view,
+ (insns[1].data() + this->reg_));
+ view += insns[1].size();
+ elfcpp::Swap<32, big_endian>::writeval(view,
+ (insns[2].data() + this->reg_));
+ }
+
+ // A register index (r0-r14), which is associated with the stub.
+ uint32_t reg_;
+};
+
// Stub factory class.
class Stub_factory
@@ -782,6 +842,16 @@ class Stub_factory
source, destination, original_insn);
}
+ // Make an ARM V4BX relocation stub.
+ // This method creates a stub from the arm_stub_v4_veneer_bx template only.
+ Arm_v4bx_stub*
+ make_arm_v4bx_stub(uint32_t reg) const
+ {
+ gold_assert(reg < 0xf);
+ return new Arm_v4bx_stub(this->stub_templates_[arm_stub_v4_veneer_bx],
+ reg);
+ }
+
private:
// Constructor and destructor are protected since we only return a single
// instance created in Stub_factory::get_instance().
@@ -804,7 +874,7 @@ class Stub_table : public Output_data
public:
Stub_table(Arm_input_section<big_endian>* owner)
: Output_data(), owner_(owner), reloc_stubs_(), cortex_a8_stubs_(),
- prev_data_size_(0), prev_addralign_(1)
+ arm_v4bx_stubs_(0xf), prev_data_size_(0), prev_addralign_(1)
{ }
~Stub_table()
@@ -818,7 +888,11 @@ class Stub_table : public Output_data
// Whether this stub table is empty.
bool
empty() const
- { return this->reloc_stubs_.empty() && this->cortex_a8_stubs_.empty(); }
+ {
+ return (this->reloc_stubs_.empty()
+ && this->cortex_a8_stubs_.empty()
+ && this->arm_v4bx_stubs_.empty());
+ }
// Return the current data size.
off_t
@@ -845,6 +919,15 @@ class Stub_table : public Output_data
this->cortex_a8_stubs_.insert(value);
}
+ // Add an ARM V4BX relocation stub. A register index will be retrieved
+ // from the stub.
+ void
+ add_arm_v4bx_stub(Arm_v4bx_stub* stub)
+ {
+ gold_assert(stub != NULL && this->arm_v4bx_stubs_[stub->reg()] == NULL);
+ this->arm_v4bx_stubs_[stub->reg()] = stub;
+ }
+
// Remove all Cortex-A8 stubs.
void
remove_all_cortex_a8_stubs();
@@ -857,6 +940,15 @@ class Stub_table : public Output_data
return (p != this->reloc_stubs_.end()) ? p->second : NULL;
}
+ // Look up an arm v4bx relocation stub using the register index.
+ // Return NULL if there is none.
+ Arm_v4bx_stub*
+ find_arm_v4bx_stub(const uint32_t reg) const
+ {
+ gold_assert(reg < 0xf);
+ return this->arm_v4bx_stubs_[reg];
+ }
+
// Relocate stubs in this stub table.
void
relocate_stubs(const Relocate_info<32, big_endian>*,
@@ -916,6 +1008,8 @@ class Stub_table : public Output_data
// List of Cortex-A8 stubs ordered by addresses of branches being
// fixed up in output.
typedef std::map<Arm_address, Cortex_a8_stub*> Cortex_a8_stub_list;
+ // List of Arm V4BX relocation stubs ordered by associated registers.
+ typedef std::vector<Arm_v4bx_stub*> Arm_v4bx_stub_list;
// Owner of this stub table.
Arm_input_section<big_endian>* owner_;
@@ -923,6 +1017,8 @@ class Stub_table : public Output_data
Reloc_stub_map reloc_stubs_;
// The cortex_a8_stubs.
Cortex_a8_stub_list cortex_a8_stubs_;
+ // The Arm V4BX relocation stubs.
+ Arm_v4bx_stub_list arm_v4bx_stubs_;
// data size of this in the previous pass.
off_t prev_data_size_;
// address alignment of this in the previous pass.
@@ -1452,7 +1548,7 @@ class Target_arm : public Sized_target<32, big_endian>
stub_factory_(Stub_factory::get_instance()), may_use_blx_(false),
should_force_pic_veneer_(false), arm_input_section_map_(),
attributes_section_data_(NULL), fix_cortex_a8_(false),
- cortex_a8_relocs_info_()
+ cortex_a8_relocs_info_(), fix_v4bx_(0)
{ }
// Whether we can use BLX.
@@ -1685,6 +1781,14 @@ class Target_arm : public Sized_target<32, big_endian>
fix_cortex_a8() const
{ return this->fix_cortex_a8_; }
+ // Whether we fix R_ARM_V4BX relocation.
+ // 0 - do not fix
+ // 1 - replace with MOV instruction (armv4 target)
+ // 2 - make interworking veneer (>= armv4t targets only)
+ int
+ fix_v4bx() const
+ { return this->fix_v4bx_; }
+
// Scan a span of THUMB code section for Cortex-A8 erratum.
void
scan_span_for_cortex_a8_erratum(Arm_relobj<big_endian>*, unsigned int,
@@ -2048,6 +2152,8 @@ class Target_arm : public Sized_target<32, big_endian>
bool fix_cortex_a8_;
// Map addresses to relocs for Cortex-A8 erratum.
Cortex_a8_relocs_info cortex_a8_relocs_info_;
+ // Whether we need to fix code for V4BX relocations.
+ int fix_v4bx_;
};
template<bool big_endian>
@@ -2745,6 +2851,49 @@ class Arm_relocate_functions : public Relocate_functions<32, big_endian>
elfcpp::Swap<16, big_endian>::writeval(wv + 1, val & 0xffff);
return This::STATUS_OKAY;
}
+
+ // R_ARM_V4BX
+ static inline typename This::Status
+ v4bx(const Relocate_info<32, big_endian>* relinfo,
+ unsigned char *view,
+ const Arm_relobj<big_endian>* object,
+ const Arm_address address,
+ const bool is_interworking)
+ {
+
+ typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
+ Valtype* wv = reinterpret_cast<Valtype*>(view);
+ Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
+
+ // Ensure that we have a BX instruction.
+ gold_assert((val & 0x0ffffff0) == 0x012fff10);
+ const uint32_t reg = (val & 0xf);
+ if (is_interworking && reg != 0xf)
+ {
+ Stub_table<big_endian>* stub_table =
+ object->stub_table(relinfo->data_shndx);
+ gold_assert(stub_table != NULL);
+
+ Arm_v4bx_stub* stub = stub_table->find_arm_v4bx_stub(reg);
+ gold_assert(stub != NULL);
+
+ int32_t veneer_address =
+ stub_table->address() + stub->offset() - 8 - address;
+ gold_assert((veneer_address <= ARM_MAX_FWD_BRANCH_OFFSET)
+ && (veneer_address >= ARM_MAX_BWD_BRANCH_OFFSET));
+ // Replace with a branch to veneer (B <addr>)
+ val = (val & 0xf0000000) | 0x0a000000
+ | ((veneer_address >> 2) & 0x00ffffff);
+ }
+ else
+ {
+ // Preserve Rm (lowest four bits) and the condition code
+ // (highest four bits). Other bits encode MOV PC,Rm.
+ val = (val & 0xf000000f) | 0x01a0f000;
+ }
+ elfcpp::Swap<32, big_endian>::writeval(wv, val);
+ return This::STATUS_OKAY;
+ }
};
// Relocate ARM long branches. This handles relocation types
@@ -3676,6 +3825,15 @@ Stub_factory::Stub_factory()
Insn_template::arm_rel_insn(0xea000000, -8) // b dest
};
+ // Stub used to provide an interworking for R_ARM_V4BX relocation
+ // (bx r[n] instruction).
+ static const Insn_template elf32_arm_stub_v4_veneer_bx[] =
+ {
+ Insn_template::arm_insn(0xe3100001), // tst r<n>, #1
+ Insn_template::arm_insn(0x01a0f000), // moveq pc, r<n>
+ Insn_template::arm_insn(0xe12fff10) // bx r<n>
+ };
+
// Fill in the stub template look-up table. Stub templates are constructed
// per instance of Stub_factory for fast look-up without locking
// in a thread-enabled environment.
@@ -3770,6 +3928,16 @@ Stub_table<big_endian>::relocate_stubs(
++p)
this->relocate_stub(p->second, relinfo, arm_target, output_section, view,
address, view_size);
+
+ // Relocate all ARM V4BX stubs.
+ for (Arm_v4bx_stub_list::iterator p = this->arm_v4bx_stubs_.begin();
+ p != this->arm_v4bx_stubs_.end();
+ ++p)
+ {
+ if (*p != NULL)
+ this->relocate_stub(*p, relinfo, arm_target, output_section, view,
+ address, view_size);
+ }
}
// Write out the stubs to file.
@@ -3811,6 +3979,22 @@ Stub_table<big_endian>::do_write(Output_file* of)
big_endian);
}
+ // Write ARM V4BX relocation stubs.
+ for (Arm_v4bx_stub_list::const_iterator p = this->arm_v4bx_stubs_.begin();
+ p != this->arm_v4bx_stubs_.end();
+ ++p)
+ {
+ if (*p == NULL)
+ continue;
+
+ Arm_address address = this->address() + (*p)->offset();
+ gold_assert(address
+ == align_address(address,
+ (*p)->stub_template()->alignment()));
+ (*p)->write(oview + (*p)->offset(), (*p)->stub_template()->size(),
+ big_endian);
+ }
+
of->write_output_view(this->offset(), oview_size, oview);
}
@@ -3847,6 +4031,19 @@ Stub_table<big_endian>::update_data_size_and_addralign()
+ stub_template->size());
}
+ for (Arm_v4bx_stub_list::const_iterator p = this->arm_v4bx_stubs_.begin();
+ p != this->arm_v4bx_stubs_.end();
+ ++p)
+ {
+ if (*p == NULL)
+ continue;
+
+ const Stub_template* stub_template = (*p)->stub_template();
+ addralign = std::max(addralign, stub_template->alignment());
+ size = (align_address(size, stub_template->alignment())
+ + stub_template->size());
+ }
+
// Check if either data size or alignment changed in this pass.
// Update prev_data_size_ and prev_addralign_. These will be used
// as the current data size and address alignment for the next pass.
@@ -3898,6 +4095,20 @@ Stub_table<big_endian>::finalize_stubs()
arm_relobj->mark_section_for_cortex_a8_workaround(stub->shndx());
}
+ for (Arm_v4bx_stub_list::const_iterator p = this->arm_v4bx_stubs_.begin();
+ p != this->arm_v4bx_stubs_.end();
+ ++p)
+ {
+ if (*p == NULL)
+ continue;
+
+ const Stub_template* stub_template = (*p)->stub_template();
+ uint64_t stub_addralign = stub_template->alignment();
+ off = align_address(off, stub_addralign);
+ (*p)->set_offset(off);
+ off += stub_template->size();
+ }
+
gold_assert(off <= this->prev_data_size_);
}
@@ -5204,6 +5415,7 @@ Target_arm<big_endian>::Scan::local(Symbol_table* symtab,
case elfcpp::R_ARM_THM_JUMP6:
case elfcpp::R_ARM_THM_JUMP8:
case elfcpp::R_ARM_THM_JUMP11:
+ case elfcpp::R_ARM_V4BX:
break;
case elfcpp::R_ARM_GOTOFF32:
@@ -5335,6 +5547,7 @@ Target_arm<big_endian>::Scan::global(Symbol_table* symtab,
case elfcpp::R_ARM_THM_JUMP6:
case elfcpp::R_ARM_THM_JUMP8:
case elfcpp::R_ARM_THM_JUMP11:
+ case elfcpp::R_ARM_V4BX:
break;
case elfcpp::R_ARM_THM_ABS5:
@@ -5603,6 +5816,13 @@ Target_arm<big_endian>::do_finalize_sections(
|| cpu_arch_profile_attr->int_value() == 0));
}
+ // Check if we can use V4BX interworking.
+ // The V4BX interworking stub contains BX instruction,
+ // which is not specified for some profiles.
+ if (this->fix_v4bx() == 2 && !this->may_use_blx())
+ gold_error(_("unable to provide V4BX reloc interworking fix up; "
+ "the target profile does not support BX instruction"));
+
// Fill in some more dynamic tags.
const Reloc_section* rel_plt = (this->plt_ == NULL
? NULL
@@ -6090,6 +6310,13 @@ Target_arm<big_endian>::Relocate::relocate(
address, thumb_bit);
break;
+ case elfcpp::R_ARM_V4BX:
+ if (target->fix_v4bx() > 0)
+ reloc_status =
+ Arm_relocate_functions::v4bx(relinfo, view, object, address,
+ (target->fix_v4bx() == 2));
+ break;
+
case elfcpp::R_ARM_TARGET1:
// This should have been mapped to another type already.
// Fall through.
@@ -6238,6 +6465,7 @@ Target_arm<big_endian>::Relocatable_size_for_reloc::get_size_for_reloc(
case elfcpp::R_ARM_MOVT_PREL:
case elfcpp::R_ARM_THM_MOVW_PREL_NC:
case elfcpp::R_ARM_THM_MOVT_PREL:
+ case elfcpp::R_ARM_V4BX:
return 4;
case elfcpp::R_ARM_TARGET1:
@@ -7382,6 +7610,29 @@ Target_arm<big_endian>::scan_reloc_for_stub(
const Arm_relobj<big_endian>* arm_relobj =
Arm_relobj<big_endian>::as_arm_relobj(relinfo->object);
+ if (r_type == elfcpp::R_ARM_V4BX)
+ {
+ const uint32_t reg = (addend & 0xf);
+ if (this->fix_v4bx() == 2 && reg < 0xf)
+ {
+ // Try looking up an existing stub from a stub table.
+ Stub_table<big_endian>* stub_table =
+ arm_relobj->stub_table(relinfo->data_shndx);
+ gold_assert(stub_table != NULL);
+
+ if (stub_table->find_arm_v4bx_stub(reg) == NULL)
+ {
+ // create a new stub and add it to stub table.
+ Arm_v4bx_stub* stub =
+ this->stub_factory().make_arm_v4bx_stub(reg);
+ gold_assert(stub != NULL);
+ stub_table->add_arm_v4bx_stub(stub);
+ }
+ }
+
+ return;
+ }
+
bool target_is_thumb;
Symbol_value<32> symval;
if (gsym != NULL)
@@ -7553,7 +7804,8 @@ Target_arm<big_endian>::scan_reloc_section_for_stubs(
&& (r_type != elfcpp::R_ARM_THM_CALL)
&& (r_type != elfcpp::R_ARM_THM_XPC22)
&& (r_type != elfcpp::R_ARM_THM_JUMP24)
- && (r_type != elfcpp::R_ARM_THM_JUMP19))
+ && (r_type != elfcpp::R_ARM_THM_JUMP19)
+ && (r_type != elfcpp::R_ARM_V4BX))
continue;
section_offset_type offset =
@@ -7568,6 +7820,18 @@ Target_arm<big_endian>::scan_reloc_section_for_stubs(
continue;
}
+ if (r_type == elfcpp::R_ARM_V4BX)
+ {
+ // Get the BX instruction.
+ typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
+ const Valtype* wv = reinterpret_cast<const Valtype*>(view + offset);
+ elfcpp::Elf_types<32>::Elf_Swxword insn =
+ elfcpp::Swap<32, big_endian>::readval(wv);
+ this->scan_reloc_for_stub(relinfo, r_type, NULL, 0, NULL,
+ insn, NULL);
+ continue;
+ }
+
// Get the addend.
Stub_addend_reader<sh_type, big_endian> stub_addend_reader;
elfcpp::Elf_types<32>::Elf_Swxword addend =