Commit Graph

573 Commits

Author SHA1 Message Date
Rui Ueyama e991a49587 Merge cases that execute the same code.
llvm-svn: 272974
2016-06-16 23:28:06 +00:00
Rui Ueyama a71ba43ed3 Early return. NFC.
llvm-svn: 272973
2016-06-16 23:28:05 +00:00
Rui Ueyama bebf4897a3 Simplify. NFC.
llvm-svn: 272972
2016-06-16 23:28:03 +00:00
Rui Ueyama 595bc5db4b Simplify *(x+y) to x[y]. NFC.
They are equivalent in C (and in C++ in this case).

llvm-svn: 272942
2016-06-16 19:48:07 +00:00
Rui Ueyama 727cd2f73f Simplify. NFC.
llvm-svn: 272924
2016-06-16 17:18:25 +00:00
Rui Ueyama e517de655b Inline a small function. NFC.
llvm-svn: 272923
2016-06-16 17:06:24 +00:00
Rui Ueyama f9d5620029 Early return. NFC.
llvm-svn: 272917
2016-06-16 16:44:52 +00:00
Rui Ueyama d089a43de4 Early return. NFC.
llvm-svn: 272915
2016-06-16 16:40:36 +00:00
Rui Ueyama 4a90f57ef2 Rename PltZero -> PltHeader.
PltZero (or PLT[0]) was an appropriate name for the little code
we have at beginning of the PLT section when we only supported x86
since the code for x86 just fits in the first PLT slot.

It's not the case anymore. The code for ARM64 occupies first two
slots, so PltZero spans PLT[0] and PLT[1], for example.
This patch renames it to avoid confusion.

llvm-svn: 272913
2016-06-16 16:28:50 +00:00
Rui Ueyama c9fee5fee6 Eliminate unnecessary call of SymbolBody::getPltVA.
For ARM and MIPS, we don't need to call this function.
This patch passes a symbol instead of a PLT entry address
so that the target handler can call it if necessary.

llvm-svn: 272910
2016-06-16 16:14:50 +00:00
Peter Smith fa4d90d5aa Add initial support for Thumb for ARMv7a
Add support for the R_ARM_THM relocations used in the objects present
    in arm-linux-gnueabihf-gcc. These are:
    R_ARM_THM_CALL
    R_ARM_THM_JUMP11
    R_ARM_THM_JUMP19
    R_ARM_THM_JUMP24
    R_ARM_THM_MOVT_ABS
    R_ARM_THM_MOVW_ABS_NC
    
    Interworking between ARM and Thumb is partially supported with BLX.
    The R_ARM_CALL relocation for ARM instructions and R_ARM_THM_CALL
    relocation for Thumb instructions will write out a BL or BLX depending
    on the state of the Target.
    
    Assumptions:
    - Availability of BLX and extended range of Thumb 4-byte Branch
      instructions.
    - In relocateOne if (Val & 0x1) == 1 target is Thumb, 0 is ARM.
      This will hold for objects that comply with the ABI for the
      ARM architecture.
    
    This is sufficient for hello world to work with a recent
    arm-linux-gnueabihf distribution.
    
    Limitations:
    No interworking for R_ARM_JUMP24, R_ARM_THM_JUMP24, R_ARM_THM_JUMP19
    and the deprecated R_ARM_PLT32 and R_ARM_PC24 instructions as these
    cannot be written out as a BLX and need a state change thunk.
    
    No range extension thunks. The R_ARM_JUMP24 and R_ARM_THM_CALL have a
    range of 16Mb

llvm-svn: 272881
2016-06-16 09:53:46 +00:00
George Rimar 2993ad2248 [ELF] - Change wording of error message.
Previously message told us that relocations could
not be used when making shared object. That was
correct because message could appear (and it is expected) 
when we linked executable.
Message should have being changed to something
that says we can't use a subset of relocations against shared
symbols.

Patch fixes the text.

llvm-svn: 272478
2016-06-11 15:59:09 +00:00
Rafael Espindola e8b8a347c7 Use errorDynRel like every other target.
llvm-svn: 272305
2016-06-09 20:42:04 +00:00
Rafael Espindola 24de767113 Rename warnDynRel.
It produces an error, so that was a bad name.

llvm-svn: 272304
2016-06-09 20:39:01 +00:00
Rafael Espindola 8dbb7e1d61 Also reject 32 bit dynamic relocs when producing executable.
They point to a shared library, so they would still overflow at runtime.

llvm-svn: 272303
2016-06-09 20:35:27 +00:00
George Rimar e6389d18dc [ELF] Replace getELFRelocationTypeName() calls with getRelName(). NFC.
That made few places in code a bit shorter.

llvm-svn: 272133
2016-06-08 12:22:26 +00:00
Rui Ueyama 3621857eac Remove break after return.
llvm-svn: 272046
2016-06-07 19:10:51 +00:00
Rui Ueyama 12ebff22cb Define a helper function to get a relocation name. NFC.
llvm-svn: 272034
2016-06-07 18:10:12 +00:00
Rui Ueyama 45a873d644 Merge duplicate code. NFC.
llvm-svn: 272032
2016-06-07 18:03:05 +00:00
Peter Smith 8646ced053 Initial support for ARM in lld.
Add support for an ARM Target and the initial set of relocations
    and PLT entries that are necessary for an ARM only hello world to
    link. This has been tested against an ARM only sysroot from the
    4.2.0 CodeSourcery Lite release.
    
    Tests have been added to test/ELF for the support that has been
    implemented.
    
    Main limitations:
    - No Thumb support
    - Relocations incomplete
    - No C++ exceptions support
    - No TLS support
    - No range extension or interworking veneer (thunk) support
    - No Build Attribute support
    - No Big-endian support
    
    The deprecated relocations R_ARM_PLT32 and R_ARM_PC24 have been
    implemented as these are used by the 4.2.0 CodeSourcery Lite release.

llvm-svn: 271993
2016-06-07 09:31:52 +00:00
Rafael Espindola e1979aed0a Implement gd to ie relaxation for aarch64.
llvm-svn: 271815
2016-06-04 23:33:31 +00:00
Rafael Espindola 69f5402b26 Use adjustRelaxExpr for tls relaxations too.
This remove some EM_386 specific code from InputSection.cpp and opens
the way for more relaxations.

llvm-svn: 271814
2016-06-04 23:22:34 +00:00
Rafael Espindola f807d47164 Rename TlsGdToLeSkip.
It will also be used for GT_TO_IE relaxations.

llvm-svn: 271813
2016-06-04 23:04:39 +00:00
Rafael Espindola 5c66b8260e Rename adjustRelaxGotExpr.
It will be used for more than just gots.

llvm-svn: 271812
2016-06-04 22:58:54 +00:00
Rafael Espindola e37d13b9ec Start adding tlsdesc support for aarch64.
This is mostly extracted from http://reviews.llvm.org/D18960.

The general idea for tlsdesc is that the two GD got entries are used
for a function pointer and its argument. The dynamic linker sets
both. In the non-dlopen case the dynamic linker sets the function to
the identity and the argument to the offset in the tls block.

All that the static linker has to do in the non-dlopen case is
relocate the code to point to the got entries and create a dynamic
relocation.

The dlopen case is more complicated, but can be implemented in another patch.

llvm-svn: 271569
2016-06-02 19:49:53 +00:00
Rafael Espindola 1c0eb972ed Simplify mask computation.
llvm-svn: 271525
2016-06-02 16:00:25 +00:00
Rafael Espindola 1016f19215 Simplify. NFC.
updateAArch64Add takes care of masking.

llvm-svn: 271524
2016-06-02 15:51:40 +00:00
Rafael Espindola 53d0a9fe40 Stort lines. NFC.
llvm-svn: 271523
2016-06-02 15:24:52 +00:00
Rafael Espindola 0f1401a8d9 Delete dead code.
AArch64 uses TLSDESC, so these are dead.

llvm-svn: 271517
2016-06-02 14:12:47 +00:00
George Rimar b720430b47 [ELF] Split too long X86_64TargetInfo::relaxGot method. NFC.
Patch adds relaxGotNoPic() method to handle no-PIC path.

llvm-svn: 271506
2016-06-02 09:22:00 +00:00
George Rimar f10c8290fa [ELF] - Implemented support for test/binop relaxations from latest ABI.
Patch implements next relaxation from latest ABI:

"Convert memory operand of test and binop into immediate operand, where binop is one of adc, add, and, cmp, or,
sbb, sub, xor instructions, when position-independent code is disabled."

It is described in System V Application Binary Interface AMD64 Architecture Processor 
Supplement Draft Version 0.99.8 (https://github.com/hjl-tools/x86-psABI/wiki/x86-64-psABI-r249.pdf, 
B.2 "B.2 Optimize GOTPCRELX Relocations").

Differential revision: http://reviews.llvm.org/D20793

llvm-svn: 271405
2016-06-01 16:45:30 +00:00
Rafael Espindola a8433c1d1b Revert "bar"
This reverts commit r271365.
Sorry, wrong branch.

llvm-svn: 271366
2016-06-01 06:15:22 +00:00
Rafael Espindola 74540516ef bar
llvm-svn: 271365
2016-06-01 06:13:54 +00:00
George Rimar a8f9cf18ad Removed redundant argument. NFC.
llvm-svn: 270847
2016-05-26 13:37:12 +00:00
George Rimar 95433df129 [ELF] - Added support for jmp/call relaxations when R_X86_64_GOTPCRELX/R_X86_64_REX_GOTPCRELX are used.
D15779 introduced basic approach to support new relaxations.
This patch implements relaxations for jmp and call instructions,
described in System V Application Binary Interface AMD64 Architecture Processor 
Supplement Draft Version 0.99.8 (https://github.com/hjl-tools/x86-psABI/wiki/x86-64-psABI-r249.pdf, 
B.2 "B.2 Optimize GOTPCRELX Relocations")

Differential revision: http://reviews.llvm.org/D20622

llvm-svn: 270721
2016-05-25 16:51:08 +00:00
George Rimar 5c33b91bbe [ELF] - Implemented optimization for R_X86_64_GOTPCREL relocation.
System V Application Binary Interface AMD64 Architecture Processor Supplement Draft Version 0.99.8 
(https://github.com/hjl-tools/x86-psABI/wiki/x86-64-psABI-r249.pdf, B.2 "B.2 Optimize GOTPCRELX Relocations")
introduces possible relaxations for R_X86_64_GOTPCRELX and R_X86_64_REX_GOTPCRELX.

That patch implements the next relaxation: 
mov foo@GOTPCREL(%rip), %reg => lea foo(%rip), %reg
and also opens door for implementing all other ones.

Implementation was suggested by Rafael Ávila de Espíndola with few additions and testcases by myself.

Differential revision: http://reviews.llvm.org/D15779

llvm-svn: 270705
2016-05-25 14:31:37 +00:00
Rui Ueyama 02fcf11a9c Fix comment.
llvm-svn: 270659
2016-05-25 04:29:53 +00:00
Rui Ueyama e66f45c6eb Reduce code duplication.
llvm-svn: 270657
2016-05-25 04:10:14 +00:00
Rafael Espindola fe3a2f1b81 Revert "Simplify. Thanks to Rui for the suggestion."
This reverts commit r270551.

Sorry, I commited the wrong branch :-(

llvm-svn: 270554
2016-05-24 12:12:06 +00:00
Rafael Espindola dba64b8ea4 Simplify. Thanks to Rui for the suggestion.
llvm-svn: 270551
2016-05-24 11:53:15 +00:00
Rafael Espindola ebed1fe0de Refactor R_RELAX_TLS_* value computation.
This makes it explicit that each R_RELAX_TLS_* is equivalent to some
other expression.

With this I think we are at a sweet spot for how much is done in
Target.cpp. I did experiment with moving *all* the value math out of it.
It has the advantage that we know the final value in target independent
code, but it gets quite verbose.

llvm-svn: 270277
2016-05-20 21:23:52 +00:00
Rafael Espindola 91e9fc0931 Document some constants. NFC.
llvm-svn: 270274
2016-05-20 21:09:59 +00:00
Rafael Espindola 74f3dbe438 Directly compute the right value for R_RELAX_TLS_GD_TO_IE.
This avoid doing math in Target.cpp to compensate.

llvm-svn: 270266
2016-05-20 20:09:35 +00:00
Rafael Espindola fb0ceb5153 Check pc relative relocations too.
llvm-svn: 270264
2016-05-20 20:02:27 +00:00
Rafael Espindola 8818ca69dc Make tp offset computation target independent.
This adds direct support for computing offsets from the thread pointer
for both variants. Of the architectures we support, variant 1 is used
only by aarch64 (but that doesn't seem to be documented anywhere.)

llvm-svn: 270243
2016-05-20 17:41:09 +00:00
Rafael Espindola e4c86d83fe Drop vestigial support for UseLazyBinding=false.
Lazy binding is quite important for use case like a shared build of
llvm. Also, if someone wants to disable it, it is better done in the
compiler (disable plt generation).

The only reason to keep it is to make it easier to add a new
architecture. But it doesn't really help much as it is possible to start
with non lazy relocation and plt code but still let the generic part
create a dedicated .got.plt and .rela.plt.

llvm-svn: 269982
2016-05-18 21:03:36 +00:00
Rafael Espindola e2f43770a4 UseLazyBinding is always true in here, simplify.
llvm-svn: 269979
2016-05-18 20:44:24 +00:00
Simon Atanasyan 4e3a15c9f3 [ELF][MIPS] Rename R_MIPS_GOT_xxx relocation expression kinds
New names reflect purpose of corresponding GOT entries better.
Both expression types related to entries allocated in the 'local'
part of MIPS GOT. R_MIPS_GOT_LOCAL_PAGE is for entries contain 'page'
addresses. R_MIPS_GOT_LOCAL is for entries contain 'full' address.

llvm-svn: 269597
2016-05-15 18:13:50 +00:00
Rafael Espindola e502751c42 Fix typo.
llvm-svn: 269072
2016-05-10 16:23:46 +00:00
Rafael Espindola 4ee6cb3a70 Document and test the first few .got.plt entries.
llvm-svn: 268945
2016-05-09 18:12:15 +00:00
Simon Atanasyan 8c8a5b5f81 [ELF][MIPS] Handling 'packed' N64 ABI relocations
MIPS N64 ABI packs multiple relocations into the single relocation
record. In general, all up to three relocations can have arbitrary types.
In fact, Clang and GCC uses only a few combinations. For now, we support
two of them. That is allow to pass at least all LLVM test suite cases.

<any relocation> / R_MIPS_SUB / R_MIPS_HI16 | R_MIPS_LO16
<any relocation> / R_MIPS_64 / R_MIPS_NONE

The first relocation is a 'real' relocation which is calculated using
the corresponding symbol's value. The second and the third relocations
used to modify result of the first one: extend it to 64-bit, extract
high or low part etc. For details, see part 2.9 'Relocation' at
https://dmz-portal.mips.com/mw/images/8/82/007-4658-001.pdf

llvm-svn: 268876
2016-05-08 14:08:40 +00:00
Simon Atanasyan 10296c2344 [ELF][MIPS] Remove redundant local variable. NFC
llvm-svn: 268852
2016-05-07 07:36:47 +00:00
Simon Atanasyan 5b9ac41c13 [ELF][MIPS] Reduce code duplication. NFC
llvm-svn: 268743
2016-05-06 15:02:54 +00:00
Simon Atanasyan 9ac819860f [ELF][MIPS] Reduce all MIPS R_GOTREL addends by MipsGPOffset in the single place. NFC
llvm-svn: 268742
2016-05-06 15:02:50 +00:00
Simon Atanasyan da83bbc1a1 [ELF][MIPS] Create combined dynamic relocation type R_MIPS_REL32/R_MIPS_64/R_MIPS_NONE
MIPS N64 ABI packs multiple relocations into the single relocation
record. Particularly it requires to represent dynamic relative
relocation as a combination of R_MIPS_REL32 and R_MIPS_64 relocations.

llvm-svn: 268565
2016-05-04 22:39:40 +00:00
Rafael Espindola de17d28a32 Don't produce relative relocs to ro segments.
We were already checking for non relative relocations.

If we ever decide to add support for rw text segments this means we will
have a single spot to add the flag.

llvm-svn: 268558
2016-05-04 21:40:07 +00:00
Simon Atanasyan be804559f8 [ELF][MIPS] R_MIPS_GOT_DISP, R_MIPS_GOT_PAGE, R_MIPS_GOT_OFST relocations support
These relocations introduced by MIPS N64 ABI. R_MIPS_GOT_DISP references
GOT entry with full symbol's address, R_MIPS_GOT_PAGE creates GOT entry
with address of memory page which includes symbol's address,
R_MIPS_GOT_OFST used together with R_MIPS_GOT_PAGE. This relocation
calculates offset from beginning of memory page to the symbol address.

llvm-svn: 268525
2016-05-04 17:47:11 +00:00
Rafael Espindola 38bd217d0c Delete getTlsGotRel.
It was an old hack to avoid duplicating expression computation, but that
is not needed with getExprRel.

llvm-svn: 268515
2016-05-04 15:51:23 +00:00
Rafael Espindola ebb04b9eb6 Simplify handling of hint relocations.
llvm-svn: 268501
2016-05-04 14:44:22 +00:00
Simon Atanasyan ae77ab71d8 [ELF][MIPS] Accept MIPS 64-bit binaries
LLD accepts MIPS 64-bit binaries, supports corresponding eulation (-m)
arguments and emits 64-bit specific ELF flags.

llvm-svn: 268024
2016-04-29 10:39:17 +00:00
Rafael Espindola b8ff59ac12 Rename isRelRelative
It was never a particularly good name and is now completely out of date.

llvm-svn: 267886
2016-04-28 14:34:39 +00:00
Rafael Espindola 7ac9628648 Reduce usage of isRelRelative.
It is now used only for relocations that only set the low bits inside a
page. Everything else is handled by getRelExpr.

I will send a another review renaming and better documenting
isRelRelative.

llvm-svn: 267705
2016-04-27 12:47:30 +00:00
Rafael Espindola 15cec298e6 Represent TOC relative relocations as GOTREL.
That way we only need to subtract the offset is relocateOne.

llvm-svn: 267702
2016-04-27 12:25:22 +00:00
Rafael Espindola 520ed3a621 Create a .got when PPC64 uses a TOC.
This simplifies the logic for computing the value of the toc base.

llvm-svn: 267701
2016-04-27 12:21:27 +00:00
Rafael Espindola 365e5f69c9 Simplify handling of R_PPC64_TOC. NFC.
llvm-svn: 267698
2016-04-27 11:54:07 +00:00
Simon Atanasyan 4ee2918e6e [ELF][MIPS] Remove getMipsGpAddr(). NFC
llvm-svn: 267673
2016-04-27 05:31:28 +00:00
Rafael Espindola 1763dc44b9 Return R_GOTREL for R_MIPS_GPREL*.
This lets Writer.cpp know that they are got relative, which will allow
further simplifications.

llvm-svn: 267613
2016-04-26 22:00:04 +00:00
Simon Atanasyan 1ef1bf87dc [ELF][MIPS] Move MIPS GOT header generation to the GotSection
MIPS is the only target requires GOT header. We already have MIPS
specific code in the `GotSection` class, so move MIPS GOT header
generation there and delete redundant stuff like `GotHeaderEntriesNum`
field and `writeGotHeader` method.

Differential Revision: http://reviews.llvm.org/D19465

llvm-svn: 267460
2016-04-25 20:25:05 +00:00
Rafael Espindola 926bff8c3e Add support for R_X86_64_PC64.
llvm-svn: 267409
2016-04-25 14:05:44 +00:00
Rafael Espindola d79073dc2a Simplify. NFC.
llvm-svn: 267396
2016-04-25 12:32:19 +00:00
Rafael Espindola a6c4d2f197 Delete needsCopyRelImpl. It is redundant with getRelExpr.
llvm-svn: 267394
2016-04-25 12:05:56 +00:00
Rui Ueyama 55274e3fcb Add a file comment about the Ulrich's document and don't repeat it in other comments.
llvm-svn: 267261
2016-04-23 01:10:15 +00:00
Rafael Espindola e26b50e71a Reduce templating. NFC.
llvm-svn: 267018
2016-04-21 17:37:11 +00:00
Rafael Espindola b312a740ae Delete the needsPlt target hook.
It can be made redundant with getRelExpr.

llvm-svn: 267012
2016-04-21 17:30:24 +00:00
Rafael Espindola 0c869a752e Moves needsPlt to Writer.cpp.
It was only used there.

llvm-svn: 267002
2016-04-21 16:57:32 +00:00
Simon Atanasyan 98a4ba54df [ELF][MIPS] Treat R_MIPS_TLS_{D}TPREL_HI16/LO16 as relative relocations
These relocations are calculated as S + A - DTPREL or S + A - TPREL,
where DTPREL = TlsVA - 0x8000, TPREL = TlsVA - 0x7000. So the result
is relative to the TLS output section and is not an absolut value
The fix allows to escape creation of unnecessary dynamic relocations
in case of DSO linking.

llvm-svn: 266923
2016-04-20 21:57:51 +00:00
Rafael Espindola c6b17bdc29 Delete refersToGotEntry.
It can be computed from the expression.

llvm-svn: 266890
2016-04-20 17:30:22 +00:00
Rafael Espindola cc36a63f0b Move canRelaxTls to Writer.cpp. NFC.
llvm-svn: 266878
2016-04-20 14:41:55 +00:00
Rafael Espindola 6eda85ac1f Delete needsDynRelative.
It is now redundant. Writer.cpp can reason that 2 dynamic relocations
are needed: one to find the final got entry address and one to fill the
got entry.

llvm-svn: 266876
2016-04-20 14:36:24 +00:00
Rafael Espindola 58cd5db4ef Simplify mips got handling.
This avoids computing the address of a position in the got just to then
subtract got->getva().

llvm-svn: 266831
2016-04-19 22:46:03 +00:00
Rafael Espindola f350d25942 Fix pr27420.
Return the right expression for R_X86_64_GOTPCRELX and
R_X86_64_REX_GOTPCRELX.

llvm-svn: 266810
2016-04-19 20:18:52 +00:00
Rafael Espindola f4c1cd4006 Fix handling of R_X86_64_GOT32.
It computes the offset to the end of .got.

llvm-svn: 266610
2016-04-18 12:58:59 +00:00
Rafael Espindola ece62b962e Simplify handling of R_X86_64_TPOFF32. NFC.
llvm-svn: 266609
2016-04-18 12:44:33 +00:00
Rafael Espindola 5bf59728e2 Remove isGotRelative.
It is now redundant with the expression. While at it, handle both "X -
Got" and "Got - PC".

llvm-svn: 266607
2016-04-18 12:31:37 +00:00
Rafael Espindola 3f5d634c73 Have getRelExpr handle all cases on x86.
This requires adding a few more expression types, but is already a small
simplification. Having Writer.cpp know the exact expression will also
allow further simplifications.

llvm-svn: 266604
2016-04-18 12:07:13 +00:00
Rafael Espindola 3c20fb4e5d Merge duplicated cases. NFC.
llvm-svn: 266601
2016-04-18 11:53:42 +00:00
Rafael Espindola 99c224787b Delete the now redundant pointsToLocalDynamicGotEntry.
llvm-svn: 266584
2016-04-18 01:34:20 +00:00
Rafael Espindola df17277d72 Have getRelExpr return the final values for tls gd.
llvm-svn: 266583
2016-04-18 01:29:15 +00:00
Rafael Espindola c4d56970dc Change getRelExpr to return the final value for TLSLD. NFC.
llvm-svn: 266580
2016-04-18 00:28:57 +00:00
Rafael Espindola 5628ee7631 Simplify got handling.
Each getRelExpr is now expected to return the correct got expression
instead of having Writer patch it up with needsGot.

llvm-svn: 266466
2016-04-15 19:14:18 +00:00
Rafael Espindola 7dd20563a2 Merge duplicated cases. NFC.
llvm-svn: 266459
2016-04-15 17:57:27 +00:00
Simon Atanasyan 1ca263c890 [ELF][MIPS] Make R_MIPS_LO16 a relative relocation if it references _gp_disp symbol
The _gp_disp symbol designates offset between start of function and 'gp'
pointer into GOT. The following code is a typical MIPS function preamble
used to setup $gp register:

lui    $gp, %hi(_gp_disp)
addi   $gp, $gp, %lo(_gp_disp)

To calculate R_MIPS_HI16 / R_MIPS_LO16 relocations results we use
the following formulas:

%hi(_gp - P + A)
%lo(_gp - P + A + 4),
where _gp is a value of _gp symbol, A is addend, and P current address.

The R_MIPS_LO16 relocation references _gp_disp symbol is always the second
instruction. That is why we need four byte adjustments. The patch assigns
R_PC type for R_MIPS_LO16 relocation and adjusts its addend by 4. That fix
R_MIPS_LO16 calculation.

For details see p. 4-19 at ftp://www.linux-mips.org/pub/linux/mips/doc/ABI/mipsabi.pdf

Differential Revision: http://reviews.llvm.org/D19115

llvm-svn: 266368
2016-04-14 21:10:05 +00:00
Rafael Espindola 3151d89595 Simplify handling of size relocations. NFC.
llvm-svn: 266355
2016-04-14 18:39:44 +00:00
Rafael Espindola e149b488af Remove the only case where we would relocate a R_386_TLS_TPOFF.
llvm-svn: 266330
2016-04-14 16:05:42 +00:00
Rafael Espindola c1c14a227e Merge duplicated cases. NFC.
llvm-svn: 266328
2016-04-14 15:56:14 +00:00
Rafael Espindola 22ef956a45 Change how we apply relocations.
With this patch we use the first scan over the relocations to remember
the information we found about them: will them be relaxed, will a plt be
used, etc.

With that the actual relocation application becomes much simpler. That
is particularly true for the interfaces in Target.h.

This unfortunately means that we now do two passes over relocations for
non SHF_ALLOC sections. I think this can be solved by factoring out the
code that scans a single relocation. It can then be used both as a scan
that record info and for a dedicated direct relocation of non SHF_ALLOC
sections.

I also think it is possible to reduce the number of enum values by
representing a target with just an OutputSection and an offset (which
can be from the start or end).

This should unblock adding features like relocation optimizations.

llvm-svn: 266158
2016-04-13 01:40:19 +00:00
Rafael Espindola 6f92e14ce2 Use DefinedSynthetic for _gp* symbols.
The test changes to put _gp* in the .got section matches what both bfd
and gold do.

llvm-svn: 266067
2016-04-12 13:26:51 +00:00
Rafael Espindola 3a72cc0083 Simplify now that we always have a .got.
llvm-svn: 266064
2016-04-12 13:23:27 +00:00
Adhemerval Zanella 15cba9e7e5 [lld] [ELF/AARCH64] Fix dynamic relocation from PIC GOT access
This patch fixes dynamic relocation creation from GOT access in dynamic
objects on aarch64. Current code creates a plt relative one
(R_AARCH64_JUMP_SLOT) instead of a got relative (R_AARCH64_GLOB_DAT).

It leads the programs fails with:

$ cat t.cc

std::string test = "hello...\n";

int main ()
{
  printf ("%s\n", test.c_str());
  return 0;
}
$ clang++ t.cc -fpic -o t
$ ./t
hello...

Segmentation fault (core dumped)

Due the fact it will try to access the plt instead of the got for
__cxa_atexit registration for the std::string destruction.  It will
lead in a bogus function address in atexit.

llvm-svn: 265784
2016-04-08 14:10:41 +00:00
Ed Schouten 39aca42df6 Sort relocations by name and size.
Approved by:	ruiu
Differential Revision:	http://reviews.llvm.org/D18835

llvm-svn: 265580
2016-04-06 18:21:07 +00:00
Ed Schouten 0a04b03ab2 Make TLS work for PIE executables on aarch64.
Similar to r265462, TLS related relocations aren't marked as relative,
meaning that we end up generating R_AARCH64_RELATIVE relocations for
them. This change adds TLS relocations that I've seen on my system. With
this patch applied CloudABI's unit testing binary now passes on aarch64.

Approved by:	ruiu
Differential Revision:	http://reviews.llvm.org/D18816

llvm-svn: 265575
2016-04-06 17:53:31 +00:00
Ed Schouten 639a333730 Make TLS work for PIE executables on x86-64.
While trying to get PIE work on CloudABI for x86-64, I noticed that even
though GNU ld would generate functional binaries, LLD would not. It
turns out that we generate relocations for referencing TLS objects
inside of the text segment, which shouldn't happen.

This change extends the isRelRelative() function to list some additional
relocation types that should be treated as relative. This makes my C
library unit testing binary work on x86-64.

Approved by:	ruiu
Differential Revision:	http://reviews.llvm.org/D18688
Fixes bug:	https://llvm.org/bugs/show_bug.cgi?id=27174

llvm-svn: 265462
2016-04-05 20:51:50 +00:00
Rui Ueyama b5792b231b Rename Other -> StOther.
"Other" as a name is too generic, so name it StOther.

llvm-svn: 265332
2016-04-04 19:09:08 +00:00
Rafael Espindola ccfe3cb3d6 Don't store an Elf_Sym for most symbols.
Our symbol representation was redundant, and some times would get out of
sync. It had an Elf_Sym, but some fields were copied to SymbolBody.

Different parts of the code were checking the bits in SymbolBody and
others were checking Elf_Sym.

There are two general approaches to fix this:
* Copy the required information and don't store and Elf_Sym.
* Don't copy the information and always use the Elf_Smy.

The second way sounds tempting, but has a big problem: we would have to
template SymbolBody. I started doing it, but it requires templeting
*everything* and creates a bit chicken and egg problem at the driver
where we have to find ELFT before we can create an ArchiveFile for
example.

As much as possible I compared the test differences with what gold and
bfd produce to make sure they are still valid. In most cases we are just
adding hidden visibility to a local symbol, which is harmless.

In most tests this is a small speedup. The only slowdown was scylla
(1.006X). The largest speedup was clang with no --build-id, -O3 or
--gc-sections (i.e.: focus on the relocations): 1.019X.

llvm-svn: 265293
2016-04-04 14:04:16 +00:00
Rafael Espindola 790db9c458 Bring r264761 back with an extra fix.
The extra fix is to note that it still requires copy relocations.

Original message:

Change how we handle R_MIPS_LO16.

Mips aligns PT_LOAD to 16 bits (0x10000). That means that the lower 16
bits are always the same, so we can, effectively, say that the
relocation is relative.

P.S.: Suggestions for a better name for the predicate are welcome :-)

llvm-svn: 265150
2016-04-01 17:00:36 +00:00
Rafael Espindola 666625b78c Pass a const pointer to getImplicitAddend. NFC.
llvm-svn: 265143
2016-04-01 14:36:09 +00:00
Simon Atanasyan 13f6da1d2c [ELF] Implement infrastructure for thunk code creation
Some targets might require creation of thunks. For example, MIPS targets
require stubs to call PIC code from non-PIC one. The patch implements
infrastructure for thunk code creation and provides support for MIPS
LA25 stubs. Any MIPS PIC code function is invoked with its address
in register $t9. So if we have a branch instruction from non-PIC code
to the PIC one we cannot make the jump directly and need to create a small
stub to save the target function address.
See page 3-38 ftp://www.linux-mips.org/pub/linux/mips/doc/ABI/mipsabi.pdf

- In relocation scanning phase we ask target about thunk creation necessity
by calling `TagetInfo::needsThunk` method. The `InputSection` class
maintains list of Symbols requires thunk creation.

- Reassigning offsets performed for each input sections after relocation
scanning complete because position of each section might change due
thunk creation.

- The patch introduces new dedicated value for DefinedSynthetic symbols
DefinedSynthetic::SectionEnd. Synthetic symbol with that value always
points to the end of the corresponding output section. That allows to
escape updating synthetic symbols if output sections sizes changes after
relocation scanning due thunk creation.

- In the `InputSection::writeTo` method we write thunks after corresponding
input section. Each thunk is written by calling `TargetInfo::writeThunk` method.

- The patch supports the only type of thunk code for each target. For now,
it is enough.

Differential Revision: http://reviews.llvm.org/D17934

llvm-svn: 265059
2016-03-31 21:26:23 +00:00
Rafael Espindola 4e5ab42e21 Pass a const SymbolBody to needsGot. NFC.
llvm-svn: 265012
2016-03-31 13:38:28 +00:00
Rafael Espindola 66ea7bb2c1 Fix the alignment check.
We have to check the final value that is written.

I don't think this has any real word implications (unless something
supports unaligned instructions), but unblocks simplifying the handling
of PC relative relocations.

llvm-svn: 265009
2016-03-31 12:09:36 +00:00
Simon Atanasyan cf8c42f546 [ELF][MIPS] Revert r264761 and add test case to demonstrate the problem
If we make R_MIPS_LO16 a relative relocation, linker:
- never creates R_MIPS_COPY relocation for it
- attempts to create R_MIPS_REL32 dynamic relocation if R_MIPS_LO16's
  target is a preemptible symbol

Differential Revision: http://reviews.llvm.org/D18607

llvm-svn: 264956
2016-03-30 22:43:14 +00:00
Rafael Espindola 287e100db2 No relocation needs bot SA and ZA.
Pass only one of them to relocateOne.

llvm-svn: 264866
2016-03-30 13:27:50 +00:00
Rafael Espindola 8cc68c313b Implement getImplicitAddend for mips.
llvm-svn: 264865
2016-03-30 13:18:08 +00:00
Rafael Espindola da99df366d Fix handling of addends on i386.
Because of merge sections it is not sufficient to just add them while
applying a relocation.

llvm-svn: 264863
2016-03-30 12:40:38 +00:00
Rafael Espindola 163974dd33 Simplify AHL handling.
This simplifies a few things

* Read the value as early as possible, instead of passing a pointer to
  the location.
* Print the warning for missing pair close to where we find out it is
  missing.
* Don't pass the value to relocateOne.

llvm-svn: 264802
2016-03-29 23:05:59 +00:00
Rafael Espindola cba3e8b4b5 Change how we handle R_MIPS_LO16.
Mips aligns PT_LOAD to 16 bits (0x10000). That means that the lower 16
bits are always the same, so we can, effectively, say that the
relocation is relative.

llvm-svn: 264761
2016-03-29 18:18:19 +00:00
George Rimar 86971050cb [ELF] - Error out when R_X86_64_PC32/R_X86_64_32 are used against preemptible symbol when linking shared object.
When R_X86_64_PC32/R_X86_64_32 relocations are
used against preemptible symbol and output is position independent,
error should be generated.

Differential revision: http://reviews.llvm.org/D18190

llvm-svn: 264707
2016-03-29 08:35:42 +00:00
Rafael Espindola 0727553405 R_AARCH64_PREL64 is relative.
llvm-svn: 264560
2016-03-28 01:31:11 +00:00
Adhemerval Zanella 3db3f6d83a Simplify AArch64 isRelRelative
This patch simplifies the isRelRelative for AArch64 and add the missing
ones for bootstrap and test-suite.  It also adds more testing for
shared object creation.

llvm-svn: 264322
2016-03-24 19:12:14 +00:00
Rafael Espindola 5432287bad Make needsPlt a plain function instead of a template.
llvm-svn: 264267
2016-03-24 12:55:27 +00:00
Rafael Espindola 88a9d7608f Mark R_AARCH64_CONDBR19 as relative.
llvm-svn: 264262
2016-03-24 12:16:46 +00:00
Rafael Espindola ffcad441fd Not every x86 relocation is relative.
Without this predicate we were not producing R_386_RELATIVE relocations.

llvm-svn: 264160
2016-03-23 14:58:25 +00:00
George Rimar 9f8f4e3944 [ELF] - Process R_X86_64_GOTPCRELX/R_X86_64_REX_GOTPCRELX relocations.
R_X86_64_GOTPCRELX and R_X86_64_REX_GOTPCRELX relocations were added in latest ABI:
https://github.com/hjl-tools/x86-psABI/wiki/x86-64-psABI-r249.pdf

They should be generated instead of R_X86_64_GOTPCREL for cases 
when relaxation is possible. Currently this patch just process them in the 
same way like R_X86_64_GOTPCREL. That should work for now
and we can implement relaxations later.

There is no testcases provided as I think there is no way to generate
such relocations using llvm-mc atm.

Differential revision: http://reviews.llvm.org/D18301

llvm-svn: 264043
2016-03-22 12:15:26 +00:00
Simon Atanasyan a8e9cb38ae [ELF][MIPS] Support R_MIPS_TLS_DTPREL_HI16/LO16 and R_MIPS_TLS_TPREL_HI16/LO16 relocations
That is initial and the most trivial patch to support TLS for MIPS targets.

llvm-svn: 263712
2016-03-17 12:36:08 +00:00
George Rimar 786e866fea [ELF] - -pie/--pic-executable option implemented
-pie
--pic-executable

Create a position independent executable.  This is currently only
 supported on ELF platforms.  Position independent executables are
 similar to shared libraries in that they are relocated by the
 dynamic linker to the virtual address the OS chooses for them
 (which can vary between invocations).  Like normal dynamically
 linked executables they can be executed and symbols defined in the
 executable cannot be overridden by shared libraries.

Differential revision: http://reviews.llvm.org/D18183

llvm-svn: 263693
2016-03-17 05:57:33 +00:00
Rafael Espindola 54bf9e1ca5 Don't pass SymbolBody to the relax* functions.
We already pass the symbol value.

llvm-svn: 263670
2016-03-16 23:01:56 +00:00
Rafael Espindola 48b9102a7a Don't create a got entry if we optimize it out.
llvm-svn: 263669
2016-03-16 22:43:36 +00:00
Rafael Espindola 89cc14fd46 Split relaxTls into one per relaxation type.
This reduces code duplication in each target.

llvm-svn: 263653
2016-03-16 19:03:58 +00:00
George Rimar ca1d1fb2d6 Error/warning/log messages should start with lowercase letters.
llvm-svn: 263549
2016-03-15 14:00:22 +00:00
Rui Ueyama 9328b2cdde Use ELFT instead of ELFFile<ELFT>.
llvm-svn: 263510
2016-03-14 23:16:09 +00:00
Rui Ueyama c4466605d8 ELF: Redefine canBeDefined as a member function of SymbolBody.
We want to make SymbolBody the central place to query symbol information.
This patch also renames canBePreempted to isPreemptible because I feel that
the latter is slightly better (the former is three words and the latter
is two words.)

llvm-svn: 263386
2016-03-13 19:48:18 +00:00
Rui Ueyama 7ede54310a Redefine isGnuIfunc as a member function of SymbolBody.
llvm-svn: 263365
2016-03-13 04:40:14 +00:00
George Rimar 777f96304e Recommit of r263252, [ELF] - Change all messages to lowercase to be consistent.
which was reverted because included
unrelative changes by mistake.

Original commit message:

[ELF] - Change all messages to lowercase to be consistent.

That is directly opposite to http://reviews.llvm.org/D18045,
which was reverted.

This patch changes all messages to start from lowercase letter if
they were not before.

That is done to be consistent with clang.

Differential revision: http://reviews.llvm.org/D18085

llvm-svn: 263337
2016-03-12 08:31:34 +00:00
Rui Ueyama f714955402 Revert r263252: "[ELF] - Change all messages to lowercase to be consistent."
This reverts commit r263252 because the change contained unrelated changes.

llvm-svn: 263272
2016-03-11 18:46:51 +00:00
George Rimar 96bcdae1a5 [ELF] - Change all messages to lowercase to be consistent.
That is directly opposite to http://reviews.llvm.org/D18045,
which was reverted.

This patch changes all messages to start from lowercase letter if
they were not before.

That is done to be consistent with clang.

Differential revision: http://reviews.llvm.org/D18085

llvm-svn: 263252
2016-03-11 16:40:55 +00:00
George Rimar 5761042db7 This reverts the r263125
It was discussed to make all messages be 
lowercase to be consistent with clang.
(also reverts the r263128 which fixed 
build bot fail after r263125)

Original commit message:
[ELF] - Consistent spelling for error/warning messages

Previously error and warnings were not consistent in lld.
Some of them started from lowercase letter, others from
uppercase. Also there was one or two which had a dot at the end.
This patch changes all messages to start from uppercase letter if
they were not before.

Differential revision: http://reviews.llvm.org/D18045

llvm-svn: 263240
2016-03-11 14:43:02 +00:00
Rafael Espindola 67d72c02bc Create a SymbolBody for locals.
pr26878 shows a case where locals have to be in the got.

llvm-svn: 263222
2016-03-11 12:06:30 +00:00
George Rimar 1452f485e2 [ELF] - Fixed handling R_X86_64_DTPOFF64 relocation relaxation
R_X86_64_DTPOFF64 was not handled properly.
Next sample app was impossible to link before this patch:

~/pg/release/bin/clang -target x86_64-pc-linux testthread.cpp -c -g
~/pg/d+a/bin/ld.lld testthread.o 
"Unknown TLS optimization" (value was 17)

__thread int x = 0;
void _start() {
}

It works fine now.

Differential revision: http://reviews.llvm.org/D18039

llvm-svn: 263150
2016-03-10 18:57:17 +00:00
George Rimar e094388861 [ELF] - Consistent spelling for error/warning messages
Previously error and warnings were not consistent in lld.
Some of them started from lowercase letter, others from
uppercase. Also there was one or two which had a dot at the end.
This patch changes all messages to start from uppercase letter if
they were not before.

Differential revision: http://reviews.llvm.org/D18045

llvm-svn: 263125
2016-03-10 16:58:34 +00:00
Rafael Espindola e02f4dfb9e Remove an unnecessary hack.
It doesn't look like anything is depending on using local dynamic tls
relocations with preemptable  symbols.

llvm-svn: 262957
2016-03-08 21:17:31 +00:00
Rafael Espindola 1f04c44885 Delete isTlsDynRel.
It was a badly specified hack for when a tls relocation should be
propagated to the dynamic relocation table.

This replaces it with a not as bad hack of saying that a local dynamic
tls relocation is never preempted.

I will try to remove even that second hack in the next patch.

llvm-svn: 262955
2016-03-08 20:24:36 +00:00
George Rimar 2f0fab53e4 [ELF] - Simplify a SymbolBody class interface a bit.
Get rid of few accessors in that class, and replace
them with direct fields access.

Differential revision: http://reviews.llvm.org/D17879

llvm-svn: 262796
2016-03-06 06:26:18 +00:00
George Rimar 4d1d16d0ed Fixed formatting issues in AArch64 target methods. NFC.
llvm-svn: 262795
2016-03-06 06:16:05 +00:00
George Rimar 7b8850f2bd [ELF] - Changed return type of Target::relaxTls()
Patch changes the return type of Target::relaxTls 
to size_t from unsigned. That is consistent with
its use from other code.

Change was reviewed http://reviews.llvm.org/D17882
and asked to commit separately from that patch above.

llvm-svn: 262794
2016-03-06 06:09:50 +00:00
George Rimar 98b060d228 [ELF] - Use the uint32_t instead of unsigned in Target class for relocations types
Patch changes all relocations types to be uint32_t and also 
fixes some dependent inconsistency in callers code.

Differential revision: http://reviews.llvm.org/D17882

llvm-svn: 262793
2016-03-06 06:01:07 +00:00
Rafael Espindola d405f4721c Refactor target independent code.
The rules for when we can relax tls relocations are target independent.
The only things that are target dependent are the relocation values.

llvm-svn: 262748
2016-03-04 21:37:09 +00:00
Rafael Espindola 1ea51d2718 Refactor duplicated code.
llvm-svn: 262720
2016-03-04 16:14:19 +00:00
Simon Atanasyan 4e18a3163d [ELF][MIPS] Factor out the code reading and sign-extending low 16-bits of 32-bit word. NFC
llvm-svn: 262708
2016-03-04 10:55:29 +00:00
Simon Atanasyan 0dcf541692 [ELF][MIPS] Factor out the code writing relocation result into low 16-bit of destination. NFC
llvm-svn: 262707
2016-03-04 10:55:24 +00:00
Simon Atanasyan 3b37785fee [ELF][MIPS] Factor out the code reading and calculating AHL addend into the separate function. NFC
llvm-svn: 262706
2016-03-04 10:55:20 +00:00
Simon Atanasyan deed55d706 [ELF][MIPS] Use writeMipsHi16 to apply result of R_MIPS_PCHI16 relocation. NFC
llvm-svn: 262705
2016-03-04 10:55:16 +00:00
Simon Atanasyan a888e6726f [ELF][MIPS] Replace S and A arguments of the writeMipsHi16 function by the single argument V. NFC
llvm-svn: 262704
2016-03-04 10:55:12 +00:00
Simon Atanasyan 3474b907dd [ELF][MIPS] s/applyMipsHi16Reloc/writeMipsHi16/ NFC
llvm-svn: 262703
2016-03-04 10:55:04 +00:00
Davide Italiano 255730cdc5 [ELF] Generalize symbol type handling.
SymbolBody constructor and friends take isFunc and isTLS boolean arguments.
ELF symbols have already a type so than be easily passed as argument.
If we want to support another type, this scheme is not good enough, that is,
the current code logic would require passing another `bool isObject` around.
Up to two argument, this stretching exercise was a little bit goofy but
still acceptable, but with more types to support, is just too much, IMHO.

Change the code so that the type is passed instead.

Differential Revision:   http://reviews.llvm.org/D17871

llvm-svn: 262684
2016-03-04 01:55:28 +00:00
Rafael Espindola 005d84430d Fix PR26818.
The hack of using a plt address as the address of an undefined function
only works in executables. Don't try it with shared libraries.

llvm-svn: 262642
2016-03-03 18:44:38 +00:00
Rafael Espindola e0df00b91f Rename elf2 to elf.
llvm-svn: 262159
2016-02-28 00:25:54 +00:00
Rafael Espindola 993f0273e3 Fix some confusion about what can be preempted.
For shared libraries we allow any weak undefined symbol to eventually be
resolved, even if we never see a definition in another .so. This matches
the behavior when handling other undefined symbols in a shared library.

For executables, we require seeing a definition in a .so or resolve it
to zero. This is also similar to how non weak symbols are handled.

llvm-svn: 262017
2016-02-26 14:27:47 +00:00
Rafael Espindola 58e4c6bdba Delete dead code.
When this code was first added it was compensating for the code deciding
to create plt entries for directly referenced functions being too aggressive.

That has since been fixed, so we don't need this anymore.

llvm-svn: 261933
2016-02-25 23:16:33 +00:00
Rafael Espindola dd7f4e33ea Move common code out of target specific hooks.
llvm-svn: 261932
2016-02-25 23:03:55 +00:00
Simon Atanasyan d040a58da3 [ELF][MIPS] Add STO_MIPS_PLT flag to the symbols require pointer equality
On MIPS we need to mark symbol which has a PLT entry and requires
pointer equality by STO_MIPS_PLT flag. That is necessary to help
dynamic linker distinguish such symbols and MIPS lazy-binding stubs.

https://sourceware.org/ml/binutils/2008-07/txt00000.txt

Differential Revision: http://reviews.llvm.org/D17593

llvm-svn: 261879
2016-02-25 16:19:15 +00:00
Simon Atanasyan 49bc69b9bb [ELF][MIPS] Enumerate absolute MIPS relocations in the isRelRelative
This commit does two related thing. At first, it enumerates supported
absolute MIPS relocations in the `MipsTargetInfo<ELFT>::isRelRelative`
method. In that case the code is shorter and the case switch does not
tend to grow. At second, it prevents R_MIPS_COPY and PLT creation for
relative relocations. For almost all relative MIPS relocations like
R_MIPS_PC19_S2, R_MIPS_PCHI16 etc it does not have a sence. The only
exception is R_MIPS_PC32. GNU linker creates a copy relocation or PLT
entry for it. But I could not find any real test case uses R_MIPS_PC32
with DSO defined symbol as a target. So for now I prefer to skip this
case to simplify the LLD code.

llvm-svn: 261822
2016-02-25 05:03:52 +00:00
Rafael Espindola a598a3a08a Mark R_AARCH64_CALL26 as relative.
llvm-svn: 261783
2016-02-24 22:07:12 +00:00
Rafael Espindola 47ed542328 Mark R_AARCH64_ADD_ABS_LO12_NC as relative.
llvm-svn: 261772
2016-02-24 21:48:06 +00:00
Rafael Espindola 57ca270b7a Mark R_AARCH64_LDST64_ABS_LO12_NC as relative.
llvm-svn: 261769
2016-02-24 20:52:58 +00:00
Rafael Espindola 40afcb547e Mark R_AARCH64_LDST32_ABS_LO12_NC as relative.
llvm-svn: 261766
2016-02-24 20:18:06 +00:00
Rafael Espindola 9a3bb54b2e R_AARCH64_LDST8_ABS_LO12_NC is effectivelly relative.
It only sets the low bits and given the page alignment of PT_LOAD the
dynamic linker can only change the high ones.

llvm-svn: 261765
2016-02-24 19:58:50 +00:00
Rafael Espindola c36e97ae39 R_AARCH64_ADR_PREL_PG_HI21 is relative.
llvm-svn: 261764
2016-02-24 19:36:30 +00:00
Rafael Espindola 795dc5a0fb Move target independent code out of x86_64 only path.
The logic for deciding if an undefined symbol should have the value of a
got entry is not target specific.

llvm-svn: 261760
2016-02-24 18:24:23 +00:00
Rafael Espindola b508f520e7 Create implicit plt entries for R_X86_64_32S.
llvm-svn: 261749
2016-02-24 16:37:47 +00:00
Rafael Espindola a4e35f7092 Mark R_AARCH64_PREL32 as relative.
llvm-svn: 261747
2016-02-24 16:15:13 +00:00
Rafael Espindola 435c00f39c Fix the aarch64 logic for dynamic relocations.
There is nothing aarch64 specific in here. If a symbol can be preempted,
we need to copy the full relocation to the dynamic linker.

If a symbol cannot be preempted, we can make the dynamic linker life
easier and produce a relative relocation.

This is directly equivalent to R_X86_64_64 to R_x86_64_RELATIVE
conversion.

llvm-svn: 261678
2016-02-23 20:19:44 +00:00
Rafael Espindola f7ae359d2c Simplify. NFC.
llvm-svn: 261668
2016-02-23 18:53:29 +00:00
Adhemerval Zanella 668ad0ffcb [lld] [ELF/AArch64] Fix R_AARCH64_ABS64 in Shared mode
This patch fixes the R_AARCH64_ABS64 relocation when used in shared mode,
where it requires a dynamic R_AARCH64_RELATIVE relocation. To correct set
the addend on the dynamic relocation (since it will be used by the dynamic
linker), a new TargetInfo specific hook was created (getDynRelativeAddend)
to get the correct addend based on relocation type.

The patch fixes the issues when creating shared library code against
{init,fini}_array, where it issues R_AARCH64_ABS64 relocation against
local symbols.

llvm-svn: 261651
2016-02-23 16:54:40 +00:00
Rafael Espindola 5e8b54afdb Remove a trivial getter.
llvm-svn: 261590
2016-02-22 23:16:05 +00:00
Rafael Espindola fb1533b326 Don't create copy relocs in shared libraries.
This fixes PR26699.

llvm-svn: 261576
2016-02-22 21:23:29 +00:00
Rafael Espindola 852860e920 make needsPlt a pure predicate.
llvm-svn: 260685
2016-02-12 15:47:37 +00:00
Adhemerval Zanella 74bcf03f87 [lld] [ELF/AArch64] Add support to some GD/LE/IS TLS relocations
This patch adds some TLS relocations and relaxations for AArch64.
Some Global-Dynamic relocation are handled by optimizing them to
Local-Exec (Initial-Exec is not yet supported). They are:

 - R_AARCH64_TLSDESC_ADR_PAGE21
 - R_AARCH64_TLSDESC_LD64_LO12_NC
 - R_AARCH64_TLSDESC_ADD_LO12_NC
 - R_AARCH64_TLSDESC_CALL

Also some Init-Exec is optimized to Local-Exec if possible. They are:

 - R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21
 - R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC

Finally some Local-Exec relocation are handled in relocateOne:

 - R_AARCH64_TLSLE_ADD_TPREL_HI12
 - R_AARCH64_TLSLE_ADD_TPREL_LO12_NC

This work is mainly for compiler bootstrap, where static binaries is
showing good progress (although shared object still lacking support
from both TLS aarch64 backend and some other issues).

llvm-svn: 260677
2016-02-12 13:43:03 +00:00
Rui Ueyama c1c282a04e ELF: Release Target at end of link().
Previously, Target held a value until a new value is assigned to the
variable. That was a benign leak -- that was not an unbounded leak
and didn't grab any resources except a small amount of memory. But
it is better to fix than leaving as is.

llvm-svn: 260592
2016-02-11 21:18:01 +00:00
George Rimar 2960c9867a [ELF] - Remove R_X86_64_GOTTPOFF from static relocation processing
R_X86_64_TPOFF64 is a dynamic relocation,
it should not appear in static relocation processing.
Patch fixes it.

Differential revision: http://reviews.llvm.org/D16880

llvm-svn: 260508
2016-02-11 11:14:46 +00:00
Rui Ueyama d41cb95621 ELF: Combine cases that has the same code.
llvm-svn: 260444
2016-02-10 22:00:21 +00:00
Simon Atanasyan 2287dc3bf8 [ELF][MIPS] Add lazy relocation support for MIPS
The patch adds lazy relocation support for MIPS and R_MIPS_26 relocation
handing.

R_MIPS_26 relocation might require PLT entry creation. In that case it
is fully supported by the patch. But if the relocation target is a local
symbol we need to use a different expression to calculate the relocation
result. This case is not implemented yet because there is no method to
get know the kind of relocation target in the `relocateOne` routine.

Differential Revision: http://reviews.llvm.org/D16982

llvm-svn: 260424
2016-02-10 19:57:19 +00:00
Rafael Espindola 96449907a5 Add support for R_X86_64_DTPOFF64.
It is used by clang to produce debug info for tls variables.

llvm-svn: 260384
2016-02-10 16:26:31 +00:00
Simon Atanasyan eae66c019b [ELF][MIPS] Group and sort initialization of MipsTargetInfo class fields. NFC
llvm-svn: 260365
2016-02-10 10:08:39 +00:00
Simon Atanasyan 6231391fa7 [ELF][MIPS] Rename MipsTargetInfo::relocateOne argument SA to S
MIPS 32-bit ABI uses REL relocation record format. We read addends from
relocation destinations right in the MipsTargetInfo::relocateOne
function.

llvm-svn: 260364
2016-02-10 10:08:35 +00:00
Rafael Espindola a0a65f973a Use the plt entry as the address of some symbols.
This is the function equivalent of a copy relocation.

Since functions are expected to change sizes, we cannot use copy
relocations. In situations where one would be needed, what is done
instead is:
* Create a plt entry
* Output an undefined symbol whose addr is the plt entry.

The dynamic linker makes sure any shared library uses the plt entry as
the function address.

llvm-svn: 260224
2016-02-09 15:11:01 +00:00
Simon Atanasyan e1bfc2e793 [ELF][MIPS] Support R_MIPS_COPY relocation
Generate R_MIPS_COPY relocation for 'static' relocations against object
symbols defined in a shared libraries.

llvm-svn: 260083
2016-02-08 10:05:13 +00:00
Simon Atanasyan e364e2e9ce [ELF][MIPS] Support R_MIPS_PC32 relocation handling
llvm-svn: 259782
2016-02-04 12:31:39 +00:00
Simon Atanasyan 4b03451cac [ELF][MIPS] Replace needsMipsLocalGot function by canBePreempted
Symbol does not need an entry i the 'global' part of GOT if it cannot be
preempted. So canBePreempted fully satisfies us at least for now.

llvm-svn: 259779
2016-02-04 11:51:45 +00:00
Rui Ueyama c2d2f44683 ELF: Remove dead code.
R_X86_64_DTPOFF64 relocs are for the dynamic linker.
Static linkers create them but don't consume them.

llvm-svn: 259679
2016-02-03 19:07:56 +00:00
Rui Ueyama 21923996f8 ELF: Do not call fatal() if relocation contraints are not satisfied.
http://reviews.llvm.org/D16648

llvm-svn: 259435
2016-02-01 23:28:21 +00:00
Rui Ueyama 3c8d049d88 Move template instantiations to end of the file.
llvm-svn: 259276
2016-01-29 23:59:15 +00:00
Rui Ueyama cf375935a9 Update comments about the entries in .got.plt.
The original comments were a bit inaccurate because there was no 4 addends.

llvm-svn: 259274
2016-01-29 23:58:03 +00:00
Rui Ueyama 8364c6269a Add comments on a mysterious value in MIPS GOT[1].
Thanks to Simon Atanasyan and Igor Kudrin for describing the code!

llvm-svn: 259259
2016-01-29 22:55:38 +00:00
Rui Ueyama 9398f86a2a Remove a parameter from Target::writePlt.
llvm-svn: 259158
2016-01-29 04:15:02 +00:00
Rui Ueyama 012eb783b3 ELF: Provide default implemenatations for simple functions.
llvm-svn: 259157
2016-01-29 04:05:09 +00:00
Rui Ueyama 57b676c546 Define stub functions instead of pure virtual functions.
To remove empty functions.

llvm-svn: 259155
2016-01-29 03:51:51 +00:00
Rui Ueyama 900e2d2578 ELF: Do not pass addresses that can be obtained using Out.
llvm-svn: 259154
2016-01-29 03:51:49 +00:00
Rui Ueyama 6251545683 Rename PltZeroEntrySize -> PltZeroSize.
This patch also fixes parameter name. They points to the beginning
of PLT or GOT tables, so GotAddr or PltAddr are better.)

llvm-svn: 259150
2016-01-29 03:00:32 +00:00
Rui Ueyama c516ae1719 ELF: Make Target's member function names shorter.
llvm-svn: 259147
2016-01-29 02:33:45 +00:00
Rui Ueyama 724d625c7a ELF: Remove accessors from Target.
These accessors do not provide values. We can simply make the variables public.

llvm-svn: 259141
2016-01-29 01:49:32 +00:00
Rui Ueyama 74b7df016f Remove unused variable.
llvm-svn: 259140
2016-01-29 01:49:29 +00:00
Rui Ueyama baf16512ea Rename isTlsOptimized -> canRelaxTls.
This function is a predicate that a given relocation can be relaxed.
The previous name implied that it returns true if a given relocation
has already been optimized away.

llvm-svn: 259128
2016-01-29 00:20:12 +00:00
Rui Ueyama 64cfffd333 ELF: Rename error -> fatal and redefine error as a non-noreturn function.
In many situations, we don't want to exit at the first error even in the
process model. For example, it is better to report all undefined symbols
rather than reporting the first one that the linker picked up randomly.

In order to handle such errors, we don't need to wrap everything with
ErrorOr (thanks for David Blaikie for pointing this out!) Instead, we
can set a flag to record the fact that we found an error and keep it
going until it reaches a reasonable checkpoint.

This idea should be applicable to other places. For example, we can
ignore broken relocations and check for errors after visiting all relocs.

In this patch, I rename error to fatal, and introduce another version of
error which doesn't call exit. That function instead sets HasError to true.
Once HasError becomes true, it stays true, so that we know that there
was an error if it is true.

I think introducing a non-noreturn error reporting function is by itself
a good idea, and it looks to me that this also provides a gradual path
towards lld-as-a-library (or at least embed-lld-to-your-program) without
sacrificing code readability with lots of ErrorOr's.

http://reviews.llvm.org/D16641

llvm-svn: 259069
2016-01-28 18:40:06 +00:00
George Rimar 237b218770 [ELF] - fix possible UB when dereferencing null
In InputSection.cpp it was possible to dereference null.
Had to change signature of relocateTlsOptimize to accept pointer instead of reference.

Differential revision: http://reviews.llvm.org/D16466

llvm-svn: 258508
2016-01-22 18:02:28 +00:00
Simon Atanasyan 56ab5f0289 [ELF][MIPS] Initial support of MIPS local GOT entries
Some MIPS relocation (for now R_MIPS_GOT16) requires creation of GOT
entries for symbol not included in the dynamic symbol table. They are
local symbols and non-local symbols with 'local' visibility. Local GOT
entries occupy continuous block between GOT header and regular GOT
entries.

The patch adds initial support for handling local GOT entries. The main
problem is allocating local GOT entries for local symbols. Such entries
should be initialized by high 16-bit of the symbol value. In ideal world
there should be no duplicated entries with the same values. But at the
moment of the `Writer::scanRelocs` call we do not know a value of the
symbol. In this patch we create new local GOT entry for each relocation
against local symbol, though we can exhaust GOT quickly. That needs to
be optimized later. When we calculate relocation we know a final symbol
value and request local GOT entry index. To do that we maintain map
between addresses and local GOT entry indexes. If we start to calculate
relocations in parallel we will have to serialize access to this map.

Differential Revision: http://reviews.llvm.org/D16324

llvm-svn: 258388
2016-01-21 05:33:23 +00:00
George Rimar ffb673515e [ELF] - R_386_GOT32 relocation calculation fix.
R_386_GOT32 has multiple descriptions:

"System V Application Binary Interface Intel386 Architecture Processor Supplement Version 1.1" (https://github.com/hjl-tools/x86-psABI/wiki/intel386-psABI-1.1.pdf), p36 contains next calculation for R_386_GOT32: G + A - GOT.
SYSTEM V APPLICATION BINARY INTERFACE 4 (https://refspecs.linuxfoundation.org/elf/abi386-4.pdf, p78) tolds us its G + A - P.
Oracle docs (https://docs.oracle.com/cd/E19455-01/816-0559/chapter6-26/index.html) says its should be G + A.

gold/bfd calculates it as "G + A - GOT", but GOT means the end of the GOT section.
Patch fixes current calculation to gold/ld behavior.

Differential revision: http://reviews.llvm.org/D15750

llvm-svn: 258115
2016-01-19 11:00:48 +00:00
Davide Italiano 2dfc5fd1ea [ELF/AArch64] Add support for R_AARCH64_LDST16_ABS_LO12_NC relocation.
Found while trying to self-host the toolchain that libLTO needs it.

llvm-svn: 257854
2016-01-15 01:49:51 +00:00
Simon Atanasyan ca558ea627 [ELF][MIPS] Create dynamic relocations for R_MIPS_32/64 relocations
llvm-svn: 257806
2016-01-14 21:34:50 +00:00
Simon Atanasyan 682aeea9de [ELF][MIPS] Ignore 'hint' relocations like R_MIPS_JALR in the `scanRelocs` method
MIPS ABI has relocations like R_MIPS_JALR which is just a hint for
linker to make some code optimization. Such relocations should not be
handled as a regular ones and lead to say dynamic relocation creation.

The patch introduces new virtual `Target::isHintReloc` method, overrides
it in the `MipsTargetInfo` class and calls it in the `Writer<ELFT>::scanRelocs`
method.

Differential Revision: http://reviews.llvm.org/D16193

llvm-svn: 257798
2016-01-14 20:42:09 +00:00
Davide Italiano 0d4fbae0e7 [ELF/AArch64] Support R_AARCH64_LDST128_ABS_LO12_NC relocation.
llvm-svn: 257731
2016-01-14 01:30:21 +00:00
George Rimar 3d737e45c0 Reapply r257588
Fix: Added missed input file.

Initial commit message:
[ELF/AArch64] - Implemented R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21 and R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC relocations

* R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21 is calculated as Page(G(GTPREL(S+A))) – Page(P), set an ADRP immediate field to bits [32:12] of X; check –2^32 ≤ X < 2^32;
* R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC is calculated as G(GTPREL(S+A)), set an LD offset field to bits [11:3] of X. No overflow check; check that X&7 = 0.

Differential revision: http://reviews.llvm.org/D16117

llvm-svn: 257596
2016-01-13 13:04:46 +00:00
George Rimar cc6c093f6f Revert r257588 as it broke buildbot
http://lab.llvm.org:8011/builders/lld-x86_64-darwin13/builds/18715/steps/test_lld/logs/stdio

llvm-svn: 257595
2016-01-13 12:58:51 +00:00
George Rimar 253dbf5405 [ELF/AArch64] - Implemented R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21 and R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC relocations
* R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21 is calculated as Page(G(GTPREL(S+A))) – Page(P), set an ADRP immediate field to bits [32:12] of X; check –2^32 ≤ X < 2^32;
* R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC is calculated as G(GTPREL(S+A)), set an LD offset field to bits [11:3] of X. No overflow check; check that X&7 = 0.

Differential revision: http://reviews.llvm.org/D16117

llvm-svn: 257588
2016-01-13 11:29:45 +00:00
Davide Italiano 8c344436c4 Initial support for PPC target in the new ELF linker.
Differential Revision:	http://reviews.llvm.org/D15968

llvm-svn: 257374
2016-01-11 19:45:33 +00:00
George Rimar 1395dbdbc6 [ELF/AARCH64] - Implemented R_AARCH64_TSTBR14 relocation.
R_AARCH64_TSTBR14 is calculated as S+A-P,
Set the immediate field of a TBZ/TBNZ instruction to bits [15:2] of X; check -2^15 ≤ X < 2^15

Differential revision: http://reviews.llvm.org/D15824

llvm-svn: 257334
2016-01-11 14:27:05 +00:00
George Rimar 4102bfbe71 [ELF/AARCH64] - Implemented R_AARCH64_CONDBR19 relocation.
R_AARCH64_CONDBR19 is calculated as S+A-P,
Set the immediate field of a conditional branch instruction to bits [20:2] of X; check -2^20 ≤ X< 2^20.

Afaik there is no document for AARCH64 instruction encoding from official for unknown reason, so 
I used gold source code and next link as a reference for implementation: http://kitoslab-eng.blogspot.ru/2012/10/armv8-aarch64-instruction-encoding.html. From which is clear that immediate field of a conditional branch instruction is 5 bits off. That is proved by output which is is equal to gold/bfd now.

Differential revision: http://reviews.llvm.org/D15809

llvm-svn: 257333
2016-01-11 14:22:00 +00:00
George Rimar a48043521f [ELF/AARCH64] - Implemented R_AARCH64_IRELATIVE relocation.
Implemented in the same way as was already done for x86/x64 targets (http://reviews.llvm.org/D15235).

Differential revision: http://reviews.llvm.org/D15806

llvm-svn: 257332
2016-01-11 14:15:17 +00:00
Rui Ueyama b705b10012 ELF: Remove dead code.
R_X86_64_PLT32 is handled in the same way as R_X86_64_PC32 by
relocateOne(), so this function does not seems to be needed.
Without this code, all tests still pass.

http://reviews.llvm.org/D15971

llvm-svn: 257203
2016-01-08 20:11:47 +00:00
Rui Ueyama 885260e480 ELF: Remove SIZE relocs from isRelRelative.
SIZE relocations are not PC-relative, so isRelRelative should return false.

llvm-svn: 257141
2016-01-08 03:25:26 +00:00
Rui Ueyama 3a7c2f6f44 ELF: Simplify Target::isSizeReloc and add comments.
All non-trivial relocation decisions need explanations like this
to help readers understand not only how relocations are handled but
why they are handled these ways. This is a start.

llvm-svn: 257119
2016-01-08 00:13:23 +00:00
Rui Ueyama 1300e6b15a Add a comment for AMDGPU relocateOne().
llvm-svn: 257095
2016-01-07 20:34:16 +00:00
Tom Stellard 80efb16aad [ELF] Add AMDGPU support
Summary: This will allow us to remove the AMDGPU support from old ELF.

Reviewers: rafael, ruiu

Differential Revision: http://reviews.llvm.org/D15895

llvm-svn: 257023
2016-01-07 03:59:08 +00:00
Rui Ueyama f53b1b7fde Update comments.
llvm-svn: 256845
2016-01-05 16:35:46 +00:00
Simon Atanasyan 57830b60dc [ELF][MIPS] Implement R_MIPS_GPREL16/R_MIPS_GPREL32 relocations
The R_MIPS_GPREL16 / R_MIPS_GPREL32 relocations use the following
expressions for calculations:
```
local symbol:  S + A + GP0 - GP
global symbol: S + A - GP

GP  - Represents the final gp value, i.e. _gp symbol
GP0 - Represents the gp value used to create the relocatable object
```
The GP0 value is taken from the .reginfo data section defined by an object
file. To implement that I keep a reference to `MipsReginfoInputSection`
in the `ObjectFile` class. This reference is used by the
`ObjectFile::getMipsGp0` method to return the GP0 value.

Differential Revision: http://reviews.llvm.org/D15760

llvm-svn: 256416
2015-12-25 13:02:13 +00:00
Rui Ueyama 3f11c8c97e Split functions and add comments. NFC.
llvm-svn: 256369
2015-12-24 08:41:12 +00:00
Rafael Espindola 4d4b06a0f8 Split Defined and DefinedElf.
This is similar to what was done for Undefined and opens the way for
having a symbol defined in bitcode.

llvm-svn: 256354
2015-12-24 00:47:42 +00:00
Simon Atanasyan 0fc0acf180 [ELF][MIPS] Support some of R_MIPS_PCxxx relocations
The patch adds support for R_MIPS_PC16, R_MIPS_PC19_S2, R_MIPS_PC21_S2,
R_MIPS_PC26_S2, R_MIPS_PCHI16, R_MIPS_PCLO16 relocations handling.

llvm-svn: 256172
2015-12-21 17:36:40 +00:00
George Rimar a07ff66112 [ELF] - Implemented R_*_IRELATIVE relocations for x86, x64 targets.
This relocation is similar to R_*_RELATIVE except that the value used in this relocation is the program address returned by the function, which takes no arguments, at the address of
the result of the corresponding R_*_RELATIVE relocation as specified in the processor-specific ABI. The purpose of this relocation to avoid name lookup for locally defined STT_GNU_IFUNC symbols at load-time.

More info can be found in ifunc.txt from https://sites.google.com/site/x32abi/documents.

Differential revision: http://reviews.llvm.org/D15235

llvm-svn: 256144
2015-12-21 10:12:06 +00:00
George Rimar bfb7bf7429 [ELF] - R_386_GOTOFF relocation implemented.
R_386_GOTOFF is calculated as S + A - GOT, where:
S - Represents the value of the symbol whose index resides in the relocation entry.
A - Represents the addend used to compute the value of the relocatable field.
GOT - Represents the address of the global offset table.

Differential revision: http://reviews.llvm.org/D15383

llvm-svn: 256143
2015-12-21 10:00:12 +00:00
George Rimar 6f17e09307 [ELF] - implemented @indntpoff (x86) relocation and its optimization.
@indntpoff is similar to @gotntpoff, but for use in position dependent code. While @gotntpoff resolves to GOT slot address relative to the
start of the GOT in the movl or addl instructions, @indntpoff resolves to the
absolute GOT slot address. ("ELF Handling For Thread-Local Storage", Ulrich Drepper).

Differential revision: http://reviews.llvm.org/D15494

llvm-svn: 255884
2015-12-17 09:32:21 +00:00
Rui Ueyama 02dfd496b0 ELF: Rename relocNeedsCopy -> needsCopyRel
Just "copy" was a bit too ambiguous to say about copy relocations.

llvm-svn: 255866
2015-12-17 01:18:40 +00:00
Rui Ueyama 62d0e3297b ELF: Rename isTLS -> isTls for consistency.
llvm-svn: 255855
2015-12-17 00:04:18 +00:00
Simon Atanasyan 350311974b [ELF][MIPS] Remove applying the redundant bit-mask
The `mipsHigh` return type is `uint16_t` so we do not need to extract
low 16-bits from return value explicitly.

llvm-svn: 255622
2015-12-15 06:06:34 +00:00
Simon Atanasyan e4361859c0 [ELF][MIPS] Ignore R_MIPS_JALR relocation for now
The `R_MIPS_JALR` is a relocation generated by gcc and gas. This
relocation points to the `jalr` instruction which might be optimized and
converted to the `b` instruction under some conditions.

Now we just ignore this relocation and keep instructions unchanged.

llvm-svn: 255453
2015-12-13 06:49:14 +00:00
Simon Atanasyan 2cd670da02 [ELF][MIPS] Fix calculation of the R_MIPS_HI16 relocation
llvm-svn: 255451
2015-12-13 06:49:01 +00:00
George Rimar 48651489b3 [ELF] - R_X86_64_SIZE64/R_X86_64_SIZE32 relocations implemented.
R_X86_64_SIZE64/R_X86_64_SIZE32 relocations were introduced in 0.98v of "System V Application Binary Interface x86-64" (http://www.x86-64.org/documentation/abi.pdf).

Calculation for them is Z + A, where:
Z - Represents the size of the symbol whose index resides in the relocation entry.
A - Represents the addend used to compute the value of the relocatable field.

Differential revision: http://reviews.llvm.org/D15335

llvm-svn: 255332
2015-12-11 08:59:37 +00:00
George Rimar b72a9c6f02 [ELF] - Resolve R_386_PLT32 statically in some cases.
If R_386_PLT32 relocation is applied against symbol that can not be preempted then it can be resolved statically.
Patch implements it for x86 target.

Differential revision: http://reviews.llvm.org/D15376

llvm-svn: 255233
2015-12-10 09:03:39 +00:00
George Rimar 2558e12bac [ELF] - Implement the TLS relocation optimization for 32-bit x86.
Implement the TLS relocation optimization for 32-bit x86 that is described in
"ELF Handling For Thread-Local Storage" by Ulrich Drepper, chapter 5,
"IA-32 Linker Optimizations". Specifically, this patch implements these
optimizations: LD->LE, GD->IE, GD->LD, and IE->LE.

Differential revision: http://reviews.llvm.org/D15292

llvm-svn: 255103
2015-12-09 09:55:54 +00:00
George Rimar c55b4e25f4 [ELF] - fixed mistype in comment, NFC.
llvm-svn: 254918
2015-12-07 16:54:56 +00:00
Igor Kudrin cfe47f5b32 [ELF/AArch64] Allow only valid dynamic relocations in the output.
All relocations, which cannot be handled by the dynamic linker,
cause a linking error "rebuild with -fPIC".

Differential revision: http://reviews.llvm.org/D15193

llvm-svn: 254840
2015-12-05 06:20:24 +00:00
George Rimar 25411f2558 [ELF] - Implemented @tlsgd optimization (GD->IE case, x64).
"Ulrich Drepper, ELF Handling For Thread-Local Storage" (5.5 x86-x64 linker optimizations, http://www.akkadia.org/drepper/tls.pdf) shows how GD can be optimized to IE.
This patch implements the optimization.

Differential revision: http://reviews.llvm.org/D15000

llvm-svn: 254713
2015-12-04 11:20:13 +00:00
Rui Ueyama 7ee3cf7d61 Fix style by sorting switch-cases.
llvm-svn: 254649
2015-12-03 20:59:51 +00:00
Rui Ueyama 24e39525d0 Remove redundant namespace specifiers.
llvm-svn: 254648
2015-12-03 20:57:45 +00:00
Igor Kudrin 9606d19a65 [ELF/AArch64] Support R_AARCH64_COPY relocation.
Generate R_AARCH64_COPY relocations for non-GOT relocations,
which reference object symbols from shared libraries.

Differential revision: http://reviews.llvm.org/D15043

llvm-svn: 254591
2015-12-03 08:05:35 +00:00
George Rimar 9db204af65 [ELF] - Implemented some GD, LD and IE TLS access models for x86 target.
Main aim of the patch to introduce basic support for TLS access models for x86 target.
Models using @tlsgd, @tlsldm and @gotntpoff are implemented.

Differential revision: http://reviews.llvm.org/D15060

llvm-svn: 254500
2015-12-02 09:58:20 +00:00
Simon Atanasyan 09b3e3685f [ELF] MIPS paired R_MIPS_HI16/LO16 relocations support
Some MIPS relocations including `R_MIPS_HI16/R_MIPS_LO16` use combined
addends. Such addend is calculated using addends of both paired relocations.
Each `R_MIPS_HI16` relocation is paired with the next `R_MIPS_LO16`
relocation. ABI requires to compute such combined addend in case of REL
relocation record format only.

For details see p. 4-17 at
ftp://www.linux-mips.org/pub/linux/mips/doc/ABI/mipsabi.pdf

This patch implements lookup of the next paired relocation suing new
`InputSectionBase::findPairedRelocLocation` method. The primary
disadvantage of this approach is that we put MIPS specific logic into
the common code. The next disadvantage is that we lookup `R_MIPS_LO16`
for each `R_MIPS_HI16` relocation, while in fact multiple `R_MIPS_HI16`
might be paired with the single `R_MIPS_LO16`. From the other side
this way allows us to keep `MipsTargetInfo` class stateless and implement
later relocation handling in parallel.

This patch does not support `R_MIPS_HI16/R_MIPS_LO16` relocations against
`_gp_disp` symbol. In that case the relocations use a special formula for
the calculation. That will be implemented later.

Differential Revision: http://reviews.llvm.org/D15112

llvm-svn: 254461
2015-12-01 21:24:45 +00:00
George Rimar b8bfd25239 [ELF] - Target interface simplification, getGotRefReloc() removed.
Removes Target::getGotRefReloc() method to simplify Target class a little.

Differential revision: http://reviews.llvm.org/D15107

llvm-svn: 254429
2015-12-01 17:52:40 +00:00
Igor Kudrin b4a0927853 [ELF] Rearrange relocation codes in natural order. NFC.
Differential revision: http://reviews.llvm.org/D15045

llvm-svn: 254393
2015-12-01 08:41:20 +00:00
Rui Ueyama 28a661ec80 ELF: Make comments consistent.
In other places, we don't have the comment. Absence of check{Int,UInt}
is the sign that no overflow check is needed.

llvm-svn: 254326
2015-11-30 21:00:53 +00:00
Igor Kudrin fea8ed50ef [ELF/AArch64] Fix overflow checks for R_AARCH64_{ABS,PREL}{16,32} relocations.
ABI specifies the allowed range for these relocations as 2^(n-1) <= X < 2^n.

The patch fixes checks and introduces precise tests for these relocations.

Differential revision: http://reviews.llvm.org/D14957

llvm-svn: 254146
2015-11-26 10:05:24 +00:00
Igor Kudrin 9b7e7db8ca [ELF] Factor out relocation checks into separate functions.
It helps to standardize common checks and unify error messages.

Differential revision: http://reviews.llvm.org/D14943

llvm-svn: 254144
2015-11-26 09:49:44 +00:00