[GOLD] Remove powerpc.cc copy of use_plt_offset
Alan Modra
amodra@gmail.com
Sun Nov 3 23:42:00 GMT 2013
This adds an extra flag for needs_dynamic_reloc() in order to remove
the copy of this function and use_plt_offset() in powerpc.cc, and
tweaks the powerpc get_reference_flags() to return the flag as
appropriate. ELFv2 does not want ELFv1 behaviour here, but note that
this patch is only partial support for ELFv2 global entry points.
I'll need to build global entry stubs as in bfd/elf64-ppc.c and make
Target_powerpc::do_dynsym_value() point at them.
OK to apply?
* symtab.h (Symbol::Reference_flags): Add FUNC_DESC_ABI.
(Symbol::needs_dynamic_reloc): Test new flag.
* powerpc.cc (needs_dynamic_reloc, use_plt_offset): Delete.
(Target_powerpc::Scan::get_reference_flags): Add target param.
Return FUNC_DESC_ABI for 64-bit ELFv1.
(Target_powerpc::Branch_info::make_stub): Adjust get_reference_flags
call.
(Target_powerpc::Scan::global): Use Symbol::needs_dynamic_reloc.
(Target_powerpc::Relocate::relocate): Use Symbol::use_plt_offset.
diff --git a/gold/powerpc.cc b/gold/powerpc.cc
index 0d6822d..ada4d0c 100644
--- a/gold/powerpc.cc
+++ b/gold/powerpc.cc
@@ -918,7 +918,7 @@ class Target_powerpc : public Sized_target<size, big_endian>
{ }
static inline int
- get_reference_flags(unsigned int r_type);
+ get_reference_flags(unsigned int r_type, const Target_powerpc* target);
inline void
local(Symbol_table* symtab, Layout* layout, Target_powerpc* target,
@@ -1429,102 +1429,6 @@ at_tls_transform(uint32_t insn, unsigned int reg)
return insn;
}
-// Modified version of symtab.h class Symbol member
-// Given a direct absolute or pc-relative static relocation against
-// the global symbol, this function returns whether a dynamic relocation
-// is needed.
-
-template<int size>
-bool
-needs_dynamic_reloc(const Symbol* gsym, int flags)
-{
- // No dynamic relocations in a static link!
- if (parameters->doing_static_link())
- return false;
-
- // A reference to an undefined symbol from an executable should be
- // statically resolved to 0, and does not need a dynamic relocation.
- // This matches gnu ld behavior.
- if (gsym->is_undefined() && !parameters->options().shared())
- return false;
-
- // A reference to an absolute symbol does not need a dynamic relocation.
- if (gsym->is_absolute())
- return false;
-
- // An absolute reference within a position-independent output file
- // will need a dynamic relocation.
- if ((flags & Symbol::ABSOLUTE_REF)
- && parameters->options().output_is_position_independent())
- return true;
-
- // A function call that can branch to a local PLT entry does not need
- // a dynamic relocation.
- if ((flags & Symbol::FUNCTION_CALL) && gsym->has_plt_offset())
- return false;
-
- // A reference to any PLT entry in a non-position-independent executable
- // does not need a dynamic relocation.
- // Except due to having function descriptors on powerpc64 we don't define
- // functions to their plt code in an executable, so this doesn't apply.
- if (size == 32
- && !parameters->options().output_is_position_independent()
- && gsym->has_plt_offset())
- return false;
-
- // A reference to a symbol defined in a dynamic object or to a
- // symbol that is preemptible will need a dynamic relocation.
- if (gsym->is_from_dynobj()
- || gsym->is_undefined()
- || gsym->is_preemptible())
- return true;
-
- // For all other cases, return FALSE.
- return false;
-}
-
-// Modified version of symtab.h class Symbol member
-// Whether we should use the PLT offset associated with a symbol for
-// a relocation. FLAGS is a set of Reference_flags.
-
-template<int size>
-bool
-use_plt_offset(const Symbol* gsym, int flags)
-{
- // If the symbol doesn't have a PLT offset, then naturally we
- // don't want to use it.
- if (!gsym->has_plt_offset())
- return false;
-
- // For a STT_GNU_IFUNC symbol we always have to use the PLT entry.
- if (gsym->type() == elfcpp::STT_GNU_IFUNC)
- return true;
-
- // If we are going to generate a dynamic relocation, then we will
- // wind up using that, so no need to use the PLT entry.
- if (needs_dynamic_reloc<size>(gsym, flags))
- return false;
-
- // If the symbol is from a dynamic object, we need to use the PLT
- // entry.
- if (gsym->is_from_dynobj())
- return true;
-
- // If we are generating a shared object, and this symbol is
- // undefined or preemptible, we need to use the PLT entry.
- if (parameters->options().shared()
- && (gsym->is_undefined() || gsym->is_preemptible()))
- return true;
-
- // If this is a call to a weak undefined symbol, we need to use
- // the PLT entry; the symbol may be defined by a library loaded
- // at runtime.
- if ((flags & Symbol::FUNCTION_CALL) && gsym->is_weak_undefined())
- return true;
-
- // Otherwise we can use the regular definition.
- return false;
-}
template<int size, bool big_endian>
class Powerpc_relocate_functions
@@ -2619,8 +2523,11 @@ Target_powerpc<size, big_endian>::Branch_info::make_stub(
if (sym != NULL && sym->is_forwarder())
sym = symtab->resolve_forwards(sym);
const Sized_symbol<size>* gsym = static_cast<const Sized_symbol<size>*>(sym);
+ Target_powerpc<size, big_endian>* target =
+ static_cast<Target_powerpc<size, big_endian>*>(
+ parameters->sized_target<size, big_endian>());
if (gsym != NULL
- ? use_plt_offset<size>(gsym, Scan::get_reference_flags(this->r_type_))
+ ? gsym->use_plt_offset(Scan::get_reference_flags(this->r_type_, target))
: this->object_->local_has_plt_offset(this->r_sym_))
{
if (stub_table == NULL)
@@ -2706,9 +2613,6 @@ Target_powerpc<size, big_endian>::Branch_info::make_stub(
if (size == 64 && is_branch_reloc(this->r_type_))
{
unsigned int dest_shndx;
- Target_powerpc<size, big_endian>* target =
- static_cast<Target_powerpc<size, big_endian>*>(
- parameters->sized_target<size, big_endian>());
to = target->symval_for_branch(symtab, to, gsym,
this->object_, &dest_shndx);
}
@@ -5002,8 +4906,12 @@ Target_powerpc<size, big_endian>::tlsld_got_offset(
template<int size, bool big_endian>
int
-Target_powerpc<size, big_endian>::Scan::get_reference_flags(unsigned int r_type)
+Target_powerpc<size, big_endian>::Scan::get_reference_flags(
+ unsigned int r_type,
+ const Target_powerpc* target)
{
+ int ref = 0;
+
switch (r_type)
{
case elfcpp::R_POWERPC_NONE:
@@ -5011,7 +4919,7 @@ Target_powerpc<size, big_endian>::Scan::get_reference_flags(unsigned int r_type)
case elfcpp::R_POWERPC_GNU_VTENTRY:
case elfcpp::R_PPC64_TOC:
// No symbol reference.
- return 0;
+ break;
case elfcpp::R_PPC64_ADDR64:
case elfcpp::R_PPC64_UADDR64:
@@ -5022,13 +4930,15 @@ Target_powerpc<size, big_endian>::Scan::get_reference_flags(unsigned int r_type)
case elfcpp::R_POWERPC_ADDR16_LO:
case elfcpp::R_POWERPC_ADDR16_HI:
case elfcpp::R_POWERPC_ADDR16_HA:
- return Symbol::ABSOLUTE_REF;
+ ref = Symbol::ABSOLUTE_REF;
+ break;
case elfcpp::R_POWERPC_ADDR24:
case elfcpp::R_POWERPC_ADDR14:
case elfcpp::R_POWERPC_ADDR14_BRTAKEN:
case elfcpp::R_POWERPC_ADDR14_BRNTAKEN:
- return Symbol::FUNCTION_CALL | Symbol::ABSOLUTE_REF;
+ ref = Symbol::FUNCTION_CALL | Symbol::ABSOLUTE_REF;
+ break;
case elfcpp::R_PPC64_REL64:
case elfcpp::R_POWERPC_REL32:
@@ -5037,14 +4947,16 @@ Target_powerpc<size, big_endian>::Scan::get_reference_flags(unsigned int r_type)
case elfcpp::R_POWERPC_REL16_LO:
case elfcpp::R_POWERPC_REL16_HI:
case elfcpp::R_POWERPC_REL16_HA:
- return Symbol::RELATIVE_REF;
+ ref = Symbol::RELATIVE_REF;
+ break;
case elfcpp::R_POWERPC_REL24:
case elfcpp::R_PPC_PLTREL24:
case elfcpp::R_POWERPC_REL14:
case elfcpp::R_POWERPC_REL14_BRTAKEN:
case elfcpp::R_POWERPC_REL14_BRNTAKEN:
- return Symbol::FUNCTION_CALL | Symbol::RELATIVE_REF;
+ ref = Symbol::FUNCTION_CALL | Symbol::RELATIVE_REF;
+ break;
case elfcpp::R_POWERPC_GOT16:
case elfcpp::R_POWERPC_GOT16_LO:
@@ -5059,11 +4971,13 @@ Target_powerpc<size, big_endian>::Scan::get_reference_flags(unsigned int r_type)
case elfcpp::R_PPC64_TOC16_DS:
case elfcpp::R_PPC64_TOC16_LO_DS:
// Absolute in GOT.
- return Symbol::ABSOLUTE_REF;
+ ref = Symbol::ABSOLUTE_REF;
+ break;
case elfcpp::R_POWERPC_GOT_TPREL16:
case elfcpp::R_POWERPC_TLS:
- return Symbol::TLS_REF;
+ ref = Symbol::TLS_REF;
+ break;
case elfcpp::R_POWERPC_COPY:
case elfcpp::R_POWERPC_GLOB_DAT:
@@ -5072,8 +4986,12 @@ Target_powerpc<size, big_endian>::Scan::get_reference_flags(unsigned int r_type)
case elfcpp::R_POWERPC_DTPMOD:
default:
// Not expected. We will give an error later.
- return 0;
+ break;
}
+
+ if (size == 64 && target->abiversion() < 2)
+ ref |= Symbol::FUNC_DESC_ABI;
+ return ref;
}
// Report an unsupported relocation against a local symbol.
@@ -5764,7 +5682,7 @@ Target_powerpc<size, big_endian>::Scan::global(
gsym->set_needs_dynsym_value();
}
// Make a dynamic relocation if necessary.
- if (needs_dynamic_reloc<size>(gsym, Scan::get_reference_flags(r_type))
+ if (gsym->needs_dynamic_reloc(Scan::get_reference_flags(r_type, target))
|| (size == 64 && is_ifunc))
{
if (gsym->may_need_copy_reloc())
@@ -5824,7 +5742,7 @@ Target_powerpc<size, big_endian>::Scan::global(
case elfcpp::R_PPC64_REL64:
case elfcpp::R_POWERPC_REL32:
// Make a dynamic relocation if necessary.
- if (needs_dynamic_reloc<size>(gsym, Scan::get_reference_flags(r_type)))
+ if (gsym->needs_dynamic_reloc(Scan::get_reference_flags(r_type, target)))
{
if (gsym->may_need_copy_reloc())
{
@@ -6601,7 +6519,7 @@ Target_powerpc<size, big_endian>::Relocate::relocate(
bool has_plt_value = false;
unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
if ((gsym != NULL
- ? use_plt_offset<size>(gsym, Scan::get_reference_flags(r_type))
+ ? gsym->use_plt_offset(Scan::get_reference_flags(r_type, target))
: object->local_has_plt_offset(r_sym))
&& (!psymval->is_ifunc_symbol()
|| Scan::reloc_needs_plt_for_ifunc(object, r_type, false)))
diff --git a/gold/symtab.h b/gold/symtab.h
index 9299ea8..1232c97 100644
--- a/gold/symtab.h
+++ b/gold/symtab.h
@@ -638,7 +638,10 @@ class Symbol
// A TLS-related reference.
TLS_REF = 4,
// A reference that can always be treated as a function call.
- FUNCTION_CALL = 8
+ FUNCTION_CALL = 8,
+ // When set, says that dynamic relocations are needed even if a
+ // symbol has a plt entry.
+ FUNC_DESC_ABI = 16,
};
// Given a direct absolute or pc-relative static relocation against
@@ -675,7 +678,8 @@ class Symbol
// A reference to any PLT entry in a non-position-independent executable
// does not need a dynamic relocation.
- if (!parameters->options().output_is_position_independent()
+ if (!(flags & FUNC_DESC_ABI)
+ && !parameters->options().output_is_position_independent()
&& this->has_plt_offset())
return false;
--
1.7.9.5
--
Alan Modra
Australia Development Lab, IBM
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