Commit Graph

15 Commits

Author SHA1 Message Date
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