Commit Graph

21 Commits

Author SHA1 Message Date
Peter Collingbourne c5391ce51e ELF: Allow thunks to change size. NFCI.
Differential Revision: https://reviews.llvm.org/D44962

llvm-svn: 328841
2018-03-29 22:32:13 +00:00
Peter Collingbourne cebab4a639 ELF: Make required Thunk methods pure virtual and remove an unused argument. NFC.
Also make certain Thunk methods non-const as this will be required for
an upcoming change.

Differential Revision: https://reviews.llvm.org/D44961

llvm-svn: 328732
2018-03-28 21:33:31 +00:00
Peter Collingbourne e9a9e0a1e7 ELF: Merge DefinedRegular and Defined.
Now that DefinedRegular is the only remaining derived class of
Defined, we can merge the two classes.

Differential Revision: https://reviews.llvm.org/D39667

llvm-svn: 317448
2017-11-06 04:35:31 +00:00
Rui Ueyama f52496e1e0 Rename SymbolBody -> Symbol
Now that we have only SymbolBody as the symbol class. So, "SymbolBody"
is a bit strange name now. This is a mechanical change generated by

  perl -i -pe s/SymbolBody/Symbol/g $(git grep -l SymbolBody lld/ELF lld/COFF)

nd clang-format-diff.

Differential Revision: https://reviews.llvm.org/D39459

llvm-svn: 317370
2017-11-03 21:21:47 +00:00
Peter Smith 6c9df3fce5 [ELF] Add support for multiple passes to createThunks()
This change allows Thunks to be added on multiple passes. To do this we must
merge only the thunks added in each pass, and deal with thunks that have
drifted out of range of their callers.

A thunk may end out of range of its caller if enough thunks are added in
between the caller and the thunk. To handle this we create another thunk.

Differential Revision: https://reviews.llvm.org/D34692

llvm-svn: 316754
2017-10-27 09:07:10 +00:00
Rui Ueyama 67533a2cb3 Define RelType to represent relocation types.
We were using uint32_t as the type of relocation kind. It has a
readability issue because what Type really means in `uint32_t Type`
is not obvious. It could be a section type, a symbol type or a
relocation type.

Since we do not do any arithemetic operations on relocation types
(e.g. adding one to R_X86_64_PC32 doesn't make sense), it would be
more natural if they are represented as enums. Unfortunately, that
is not doable because relocation type definitions are spread into
multiple header files.

So I decided to use typedef. This still should be better than the
plain uint32_t because the intended type is now obvious.

llvm-svn: 315525
2017-10-11 22:49:24 +00:00
George Rimar b939d32f53 [ELF] - Fix member name: alignment -> Alignment. NFC.
llvm-svn: 308300
2017-07-18 11:59:19 +00:00
Peter Smith 7d66e849fc [ELF] Introduce Thunk reuse compatibility
On ARM the interworking thunks are only produced for branch instructions
that can't be changed into a blx instruction so only Thumb callers would
call Thumb thunks and only ARM callers would call ARM thunks. With range
extension thunks branch and link instructions may need a Thunk. These
instructions can be rewritten as a blx and can use either ARM or Thumb
thunks.

We introduce an isCompatibleWith() function so that a caller can check if
an existing Thunk is compatible before reusing it.

Differential Revision: https://reviews.llvm.org/D34035

llvm-svn: 307132
2017-07-05 09:36:03 +00:00
George Rimar ec84ffc529 [ELF] - Detemplate Thunk creation.
Nothing special here, just detemplates code that became possible 
to detemplate after recent commits in a straghtforward way.

Differential revision: https://reviews.llvm.org/D33234

llvm-svn: 303237
2017-05-17 07:10:59 +00:00
George Rimar 7b8270424e [ELF] Detemplate ThunkSection and Thunk classes. NFC.
llvm-svn: 297939
2017-03-16 10:40:50 +00:00
Rafael Espindola 24e6f363c5 Merge OutputSectionBase and OutputSection. NFC.
Now that all special sections are SyntheticSections, we only need one
OutputSection class.

llvm-svn: 296127
2017-02-24 15:07:30 +00:00
Rafael Espindola 774ea7d0a9 Make InputSection a class. NFC.
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
2017-02-23 16:49:07 +00:00
Peter Smith 3a52eb0054 [ELF] Use SyntheticSections for Thunks
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
2017-02-01 10:26:03 +00:00
Rui Ueyama f20ee9f11a Revert "[ELF][ARM] Use SyntheticSections for Thunks"
This reverts commit r293283 because it broke MSVC build.

llvm-svn: 293352
2017-01-28 00:48:06 +00:00
Peter Smith 5191c6f945 [ELF][ARM] Use SyntheticSections for Thunks
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
2017-01-27 13:10:16 +00:00
Rui Ueyama 0d410c265c Attempt to fix buildbots.
llvm-svn: 275001
2016-07-09 23:02:37 +00:00
Rui Ueyama 95d2a9f91a Remove unused forward declarations.
llvm-svn: 274998
2016-07-09 22:54:27 +00:00
Rui Ueyama 3d2bbb13d0 Make ARM thunks consistent with MIPS in coding style.
Although they are in the same .cpp file, the way they were written
were slightly different, so they looked more different than they were.
This patch makes their styles consistent.

llvm-svn: 274996
2016-07-09 22:52:30 +00:00
Peter Smith fb05cd997c Recommit R274836 Add Thunk support framework for ARM and Mips
The TinyPtrVector of const Thunk<ELFT>* in InputSections.h can cause 
build failures on certain compiler/library combinations when Thunk<ELFT> 
is not a complete type or is an abstract class. Fixed by making Thunk<ELFT>
non Abstract.

type or is an abstract class 

llvm-svn: 274863
2016-07-08 16:10:27 +00:00
Peter Smith eeb827447e Revert R274836 Add Thunk support framework for ARM and Mips
This seems to be causing a buildbot failure on lld-x86_64-freebsd. Will
reproduce locally and fix. 

llvm-svn: 274841
2016-07-08 12:25:50 +00:00
Peter Smith de01b98a26 Add Thunk support framework for ARM and Mips
Generalise the Mips LA25 Thunk code and implement ARM and Thumb
    interworking Thunks.
    
    - Introduce a new module Thunks.cpp to store the Target Specific Thunk
      implementations.
    - DefinedRegular and Shared have a ThunkData field to record Thunk.
    - A Target can have more than one type of Thunk.
    - Support PC-relative calls to Thunks.
    - Support Thunks to PLT entries.
    - Existing Mips LA25 Thunk code integrated.
    - Support for ARMv7A interworking Thunks.
    
    Limitations:
    - Only one Thunk per SymbolBody, this is sufficient for all currently
      implemented Thunks.
    - ARM thunks assume presence of V6T2 MOVT and MOVW instructions.

    Differential revision: http://reviews.llvm.org/D21891

llvm-svn: 274836
2016-07-08 11:13:40 +00:00