llvm-svn: 297287

    
This change moves the calls to finalizeContent() for each synthetic section
before createThunks(). This will allow us to assign addresses prior to
calling createThunks(). As addition of thunks may add to the static
symbol table and may affect the size of the mips got section we introduce a
couple of additional member functions to update these values.
    
Differential revision: https://reviews.llvm.org/D29983

llvm-svn: 297277

    
This change fixes a bug in which the Mips LA25 Thunks are always assigned
to the same Output section as the caller and not the callee as expected.

Differential Revision: https://reviews.llvm.org/D30637

llvm-svn: 297135

llvm-svn: 297107

llvm-svn: 297077

llvm-svn: 297012

In compare with D30458, this makes Bss/BssRelRo to be pure
synthetic sections.

That removes CopyRelSection class completely, making
Bss/BssRelRo to be just regular synthetics.

SharedSymbols involved in creating copy relocations are
converted to DefinedRegular, what also simplifies things.

Differential revision: https://reviews.llvm.org/D30541

llvm-svn: 297008

In many places we reset Size to 0 before calling assignOffsets()
manually. Sometimes we don't do that. 
It looks we can just always do that inside.

Previous code had:
template <class ELFT> void OutputSection::assignOffsets() {
  uint64_t Off = Size;

And tests feels fine with Off = 0. 
I think Off = Size make no sence.

Differential revision: https://reviews.llvm.org/D30463

llvm-svn: 296609

Differential Revision: https://reviews.llvm.org/D30348

llvm-svn: 296508

llvm-svn: 296307

Differential Revision: https://reviews.llvm.org/D30351

llvm-svn: 296303

Now that all special sections are SyntheticSections, we only need one
OutputSection class.

llvm-svn: 296127

With the current design an InputSection is basically anything that
goes directly in a OutputSection. That includes plain input section
but also synthetic sections, so this should probably not be a
template.

llvm-svn: 295993

We shouldn't report an error for R_*_NONE relocs since we're emitting
them when writing relocations to discarded sections.

Differential Revision: https://reviews.llvm.org/D30279

llvm-svn: 295936

Removing this template is not a big win by itself, but opens the way
for removing more templates.

llvm-svn: 295923

This option disable creating copy relocations. ld.bfd and ld.gold
have the same option.

llvm-svn: 295772

llvm-svn: 295632

llvm-svn: 295622

The previous name caused a little confusion because the function not
only returns aliases but a given symbol itself too.

llvm-svn: 295408

llvm-svn: 295289

llvm-svn: 295288

This patch removes NeedsCopyOrPltAddr and instead add two variables,
NeedsCopy and NeedsPltAddr. This uses one more bit in Symbol class,
but the actual size doesn't increase because we had unused bits.
This should improve code readability.

llvm-svn: 295287

This is slightly inefficient than the previous code, but that is really
negligible as this function is usually called at most only a few times.

llvm-svn: 295282

Previously, space in a BSS section for copy relocations are reserved
in a special way. We directly manipulated size of the BSS section.
r294577 changed the way of doing it. Now, we create an instance of
CopyRelSection (which is a synthetic input section) for each copy
relocation.

This patch removes the remains of the old way and add CopyRelSections
to BSS sections using `addSections` function, which is the usual
way to add an input section to an output section.

llvm-svn: 295278

In the target dependent code we already always return a int64_t. In
the target independent code we carefully use uintX_t, which has the
same result given 2 complement rules.

This just simplifies the code to use int64_t everywhere.

llvm-svn: 295263

llvm-svn: 295031

    
When we need a copy relocation we create a synthetic SHT_NOBITS
section that contains the right amount of ZI and assign it to either
.bss or .rel.ro.bss as appropriate. This allows the dynamic relocation
to be placed on the InputSection, removing the last case where a
dynamic relocation is stored as an offset from the OutputSection. This
has the side effect that we can run assignOffsets() after scanRelocs()
without losing the additional ZI needed for the copy relocations.

Differential Revision: https://reviews.llvm.org/D29637

llvm-svn: 294577

    
Thunks are now implemented by redirecting the relocation to the
symbol S, to a symbol TS in a Thunk. The Thunk will transfer control
to S. This has the following implications:
- All the side-effects of Thunks happen within createThunks()
- Thunks are no longer stored in InputSections and Symbols no longer
  need to hold a pointer to a Thunk
- The synthetic Thunk sections need to be merged into OutputSections
    
This implementation is almost a direct conversion of the existing
Thunks with the following exceptions:
- Mips LA25 Thunks are placed before the InputSection that defines
  the symbol that needs a Thunk.
- All ARM Thunks are placed at the end of the OutputSection of the
  first caller to the Thunk.
    
Range extension Thunks are not supported yet so it is optimistically
assumed that all Thunks can be reused.

This is a recommit of r293283 with a fixed comparison predicate as
std::merge requires a strict weak ordering.

Differential revision: https://reviews.llvm.org/D29327

llvm-svn: 293757

This reverts commit r293283 because it broke MSVC build.

llvm-svn: 293352

Now reportUndefined only has to look at Config->UnresolvedSymbols and
the symbol. getUnresolvedSymbolOption does all the hard work of
mapping options like -shared and -z defs to one of the
UnresolvedPolicy enum entries.

The critical fix is that now "-z defs --warn-unresolved-symbols" only
warns.

llvm-svn: 293290

    
Thunks are now implemented by redirecting the relocation to the
symbol S, to a symbol TS in a Thunk. The Thunk will transfer control
to S. This has the following implications:
- All the side-effects of Thunks happen within createThunks()
- Thunks are no longer stored in InputSections and Symbols no longer
  need to hold a pointer to a Thunk
- The synthetic Thunk sections need to be merged into OutputSections
    
This implementation is almost a direct conversion of the existing
Thunks with the following exceptions:
- Mips LA25 Thunks are placed before the InputSection that defines
  the symbol that needs a Thunk.
- All ARM Thunks are placed at the end of the OutputSection of the
  first caller to the Thunk.
    
Range extension Thunks are not supported yet so it is optimistically
assumed that all Thunks can be reused.

Differential Revision:  https://reviews.llvm.org/D29129

llvm-svn: 293283

    
Include removal of call to getThunkExpr() as it has already been
called and recorded by scanRelocs()
    
Cleanup suggestions by Rafael.

llvm-svn: 292614

    
A necessary first step towards range extension thunks is to delay
the creation of thunks until the layout of InputSections within
OutputSections has been done.
    
The change scans the relocations directly from InputSections rather
than looking in the ELF File the InputSection came from. This will
allow a future change to redirect the relocations to symbols defined
by Thunks rather than indirect when resolving relocations.
    
A side-effect of moving ThunkCreation is that the OutSecOff of
InputSections may change in an OutputSection that contains Thunks.
In well behaved programs thunks are not in OutputSections with
dynamic relocations.
    
Differential Revision: https://reviews.llvm.org/D28811

llvm-svn: 292359

When reserving copy relocation space for a shared symbol, scan the DSO's
program headers to see if the symbol is in a read-only segment. If so,
reserve space for that symbol in a new synthetic section named .bss.rel.ro
which will be covered by the relro program header.

This fixes the security issue disclosed on the binutils mailing list at:
https://sourceware.org/ml/libc-alpha/2016-12/msg00914.html

Differential Revision: https://reviews.llvm.org/D28272

llvm-svn: 291524

llvm-svn: 290112

AArch64 TLSDESC for local symbol in shared objects are implemented in a
arch specific manner where the TLSDESC dynamic relocation addend is the
symbol VM inside the TLS block. For instance, with a shared library
created from the code:

--
static __thread int32_t x1;
static __thread int64_t x2;

int32_t foo1 (int32_t x)
{
  x1 += x;
  return x;
}

int64_t foo2 (int64_t x)
{
  x2 += x;
  return x;
}
--

The dynamic relocation should be create as:

Relocations [
  Section (N) .rela.dyn {
    <Address1> R_AARCH64_TLSDESC - 0x0
    <Address2> R_AARCH64_TLSDESC - 0x8
  }
]

Where 0x0 addend in first dynamic relocation is the address of 'x1'
in TLS block and '0x8' is the address of 'x2'.

Checked against test-suite on aarch64-linux-gnu.

llvm-svn: 290099

llvm-svn: 289550

This change introduces new synthetic sections IpltSection, IgotPltSection
that represent the ifunc entries that would previously have been put in
the PltSection and the GotPltSection. The separation makes sure that
the R_*_IRELATIVE relocations are placed after the non R_*_IRELATIVE
relocations, which permits ifunc resolvers to know that the .got.plt
slots will be initialized prior to the resolver being called.

A secondary benefit is that for ARM we can move the IgotPltSection and its
dynamic relocations to the .got and .rel.dyn as the ARM glibc expects all
the R_*_IRELATIVE relocations to be in the .rel.dyn

Differential revision: https://reviews.llvm.org/D27406

llvm-svn: 289045

These MIPS specific symbols should be global because in general they can
have an arbitrary value. By default this value is a fixed offset from .got
section.

This patch adds more checks to the mips-gp-local.s test case but marks
it as XFAIL because LLD does not allow redefinition of absolute symbols
value by a linker script. This should be fixed by D27276.

Differential revision: https://reviews.llvm.org/D27524

llvm-svn: 289025

For preemptable symbols the dynamic linker does all the work. Trying
to compute the addend is at best wasteful and can also lead to crashes
in cases of programs that uses tls but doesn't define any tls
variables.

llvm-svn: 288803