Commit Graph

2592 Commits

Author SHA1 Message Date
David Blaikie 5106ce7897 Remove StringMap::GetOrCreateValue in favor of StringMap::insert
Having two ways to do this doesn't seem terribly helpful and
consistently using the insert version (which we already has) seems like
it'll make the code easier to understand to anyone working with standard
data structures. (I also updated many references to the Entry's
key and value to use first() and second instead of getKey{Data,Length,}
and get/setValue - for similar consistency)

Also removes the GetOrCreateValue functions so there's less surface area
to StringMap to fix/improve/change/accommodate move semantics, etc.

llvm-svn: 222319
2014-11-19 05:49:42 +00:00
Frederic Riss 3f1a0a7ce2 COFF: Add support for Dwarf accelerator tables.
This allows COFF targets to emit accelerator tables
when requested by -dwarf-accel-tables=Enable instead
of aborting. The test DebugInfo/cross-cu-inlining.ll
covers this on COFF platforms.

llvm-svn: 222034
2014-11-14 20:33:40 +00:00
Rafael Espindola 6c933979d3 Fix a regression on the disassembling C API.
The fix is easy. Unfortunately, we had 0 tests, so adding one was somewhat
complicated.

Thanks to Kevin Enderby for the report.

llvm-svn: 221899
2014-11-13 16:52:07 +00:00
Justin Hibbits a88b605721 Add support for small-model PIC for PowerPC.
Summary:
Large-model was added first.  With the addition of support for multiple PIC
models in LLVM, now add small-model PIC for 32-bit PowerPC, SysV4 ABI.  This
generates more optimal code, for shared libraries with less than about 16380
data objects.

Test Plan: Test cases added or updated

Reviewers: joerg, hfinkel

Reviewed By: hfinkel

Subscribers: jholewinski, mcrosier, emaste, llvm-commits

Differential Revision: http://reviews.llvm.org/D5399

llvm-svn: 221791
2014-11-12 15:16:30 +00:00
Rafael Espindola cac0088e91 Remove the now unused StringRefMemoryObject.h.
llvm-svn: 221755
2014-11-12 02:13:27 +00:00
Rafael Espindola 7fc5b87480 Pass an ArrayRef to MCDisassembler::getInstruction.
With this patch MCDisassembler::getInstruction takes an ArrayRef<uint8_t>
instead of a MemoryObject.

Even on X86 there is a maximum size an instruction can have. Given
that, it seems way simpler and more efficient to just pass an ArrayRef
to the disassembler instead of a MemoryObject and have it do a virtual
call every time it wants some extra bytes.

llvm-svn: 221751
2014-11-12 02:04:27 +00:00
David Majnemer 2cc4bc77bf MC, COFF: Use relocations for function references inside the section
Referencing one symbol from another in the same section does not
generally require a relocation.  However, the MS linker has a feature
called /INCREMENTAL which enables incremental links.  It achieves this
by creating thunks to the actual function and redirecting all
relocations to point to the thunk.

This breaks down with the old scheme if you have a function which
references, say, itself.  On x86_64, we would use %rip relative
addressing to reference the start of the function from out current
position.  This would lead to miscompiles because other references might
reference the thunk instead, breaking function pointer equality.

This fixes PR21520.

llvm-svn: 221678
2014-11-11 08:43:57 +00:00
Rafael Espindola 804f43c655 Add const. NFC.
This adds const to a few methods that already return const references or
creates a const version when they reterun non-const references.

llvm-svn: 221666
2014-11-11 05:11:47 +00:00
Nico Weber 7f654a8e8f speling.
llvm-svn: 221652
2014-11-11 01:13:42 +00:00
Rafael Espindola 1d7d4eb15c Use a StringRefMemoryObject. NFC.
llvm-svn: 221503
2014-11-07 01:09:51 +00:00
Petar Jovanovic 35f05747f3 [mips64] Fix MIPS64 exception personality encoding
Remove dynamic relocations of __gxx_personality_v0 from the .eh_frame.
The MIPS64 follow-up of the MIPS32 fix (rL209907).

Patch by Vladimir Stefanovic.

Differential Revision: http://reviews.llvm.org/D6141

llvm-svn: 221408
2014-11-05 22:42:31 +00:00
Rafael Espindola bfd0f01dd7 Don't produce relocations for a difference in a section with no symbols.
We were producing a relocation for
----------------
.section foo,bar
La:
Lb:
 .long   La-Lb
--------------

but not for

---------------------
  .section foo,bar
zed:
La:
Lb:
 .long   La-Lb
----------------

This patch handles the case where both fragments are part of the first atom
in a section and there is no corresponding symbol to that atom.

This fixes pr21328.

llvm-svn: 221304
2014-11-04 22:10:33 +00:00
Oliver Stannard cf6bfb1dd0 Revert r221150, as it broke sanitizer tests
llvm-svn: 221151
2014-11-03 12:19:03 +00:00
Oliver Stannard 652ec6ee89 Emit .eh_frame with relocations to functions, rather than sections
When LLVM emits DWARF call frame information, it currently creates a local,
section-relative symbol in the code section, which is pointed to by a
relocation on the .eh_frame section. However, for C++ we emit some functions in
section groups, and the SysV ABI has some rules to make it easier to remove
these sections
(http://www.sco.com/developers/gabi/latest/ch4.sheader.html#section_group_rules):

  A symbol table entry with STB_LOCAL binding that is defined relative to one
  of a group's sections, and that is contained in a symbol table section that is
  not part of the group, must be discarded if the group members are discarded.
  References to this symbol table entry from outside the group are not allowed.

This means that we need to use the function symbol for the relocation, not a
temporary symbol.

There was a comment in the code claiming that the local symbol was used to
avoid creating a relocation, but a relocation must be created anyway as the
code and CFI are in different sections.

llvm-svn: 221150
2014-11-03 12:02:51 +00:00
David Majnemer ac7dc6e701 Attempt to fix the build after r220439
llvm-svn: 220440
2014-10-22 22:46:05 +00:00
Derek Schuff 5f708e5ec8 [MC] Attach labels to existing fragments instead of using a separate fragment
Summary:
Currently when emitting a label, a new data fragment is created for it if the
current fragment isn't a data fragment.
This change instead enqueues the label and attaches it to the next fragment
(e.g. created for the next instruction) if possible.

When bundle alignment is not enabled, this has no functionality change (it
just results in fewer extra fragments being created). For bundle alignment,
previously labels would point to the beginning of the bundle padding instead
of the beginning of the emitted instruction. This was not only less efficient
(e.g. jumping to the nops instead of past them) but also led to miscalculation
of the address of the GOT (since MC uses a label difference rather than
emitting a "." symbol).

Fixes https://code.google.com/p/nativeclient/issues/detail?id=3982

Test Plan: regression test attached

Reviewers: jvoung, eliben

Subscribers: jfb, llvm-commits

Differential Revision: http://reviews.llvm.org/D5915

llvm-svn: 220439
2014-10-22 22:38:06 +00:00
Rafael Espindola f03ae4efa7 Drop support for an old version of ld64 (from darwin 9).
llvm-svn: 220310
2014-10-21 18:31:09 +00:00
Rafael Espindola c606bfe660 Fix a bit of confusion about .set and produce more readable assembly.
Every target we support has support for assembly that looks like

a = b - c
.long a

What is special about MachO is that the above combination suppresses the
production of a relocation.

With this change we avoid producing the intermediary labels when they don't
add any value.

llvm-svn: 220256
2014-10-21 01:17:30 +00:00
Rafael Espindola b66130209b Add back commits r219835 and a fixed version of r219829.
The only difference from r219829 is using

getOrCreateSectionSymbol(*ELFSec)

instead of

GetOrCreateSymbol(ELFSec->getSectionName())

in ELFObjectWriter which causes us to use the correct section symbol even if
we have multiple sections with the same name.

Original messages:

r219829:
Correctly handle references to section symbols.

When processing assembly like

.long .text

we were creating a new undefined symbol .text. GAS on the other hand would
handle that as a reference to the .text section.

This patch implements that by creating the section symbols earlier so that
they are visible during asm parsing.

The patch also updates llvm-readobj to print the symbol number in the relocation
dump so that the test can differentiate between two sections with the same name.

r219835:
Allow forward references to section symbols.

llvm-svn: 220021
2014-10-17 01:48:58 +00:00
Rafael Espindola 4544a4062c Revert commit r219835 and r219829.
Revert "Correctly handle references to section symbols."
Revert "Allow forward references to section symbols."

Rui found a regression I am debugging.

llvm-svn: 220010
2014-10-17 01:06:02 +00:00
Rafael Espindola 78206c3576 Allow forward references to section symbols.
llvm-svn: 219835
2014-10-15 19:30:18 +00:00
Rafael Espindola a74b5e6823 Correctly handle references to section symbols.
When processing assembly like

.long .text

we were creating a new undefined symbol .text. GAS on the other hand would
handle that as a reference to the .text section.

This patch implements that by creating the section symbols earlier so that
they are visible during asm parsing.

The patch also updates llvm-readobj to print the symbol number in the relocation
dump so that the test can differentiate between two sections with the same name.

llvm-svn: 219829
2014-10-15 18:55:30 +00:00
Derek Schuff 05fb735f3a [MC] Make bundle alignment mode setting idempotent and support nested bundles
Summary:
Currently an error is thrown if bundle alignment mode is set more than once
per module (either via the API or the .bundle_align_mode directive). This
change allows setting it multiple times as long as the alignment doesn't
change.

Also nested bundle_lock groups are currently not allowed. This change allows
them, with the effect that the group stays open until all nests are exited,
and if any of the bundle_lock directives has the align_to_end flag, the
group becomes align_to_end.

These changes make the bundle aligment simpler to use in the compiler, and
also better match the corresponding support in GNU as.

Reviewers: jvoung, eliben

Differential Revision: http://reviews.llvm.org/D5801

llvm-svn: 219811
2014-10-15 17:10:04 +00:00
Rafael Espindola 7b61ddfa6e Simplify handling of --noexecstack by using getNonexecutableStackSection.
llvm-svn: 219799
2014-10-15 16:12:52 +00:00
Rafael Espindola ad33dd2914 Move getNonexecutableStackSection up to the base ELF class.
The .note.GNU-stack section is not SystemZ/X86 specific.

llvm-svn: 219796
2014-10-15 15:44:16 +00:00
Rafael Espindola c57477912a Remove method that is identical to the base class one.
llvm-svn: 219700
2014-10-14 17:38:38 +00:00
Benjamin Kramer dd13643b97 MC: Shrink MCSymbolRefExpr by only storing the bits we need.
32 -> 16 bytes on x86_64. NFC.

llvm-svn: 219574
2014-10-11 17:57:27 +00:00
Benjamin Kramer 3e67db92bc MC: Bit pack MCSymbolData.
On x86_64 this brings it from 80 bytes to 64 bytes. Also make any member
variables private and clean up uses to go through the existing accessors.

NFC.

llvm-svn: 219573
2014-10-11 15:07:21 +00:00
Sanjay Patel 352fb46d4f delete function name from comment
llvm-svn: 219443
2014-10-09 21:23:39 +00:00
Timur Iskhodzhanov 5fcaeebb72 Fix COFF section index relocation should be 16 bits, not 32
Original patch by Andrey Guskov!
http://reviews.llvm.org/D5651

llvm-svn: 219327
2014-10-08 18:01:49 +00:00
David Majnemer d7586046ee COFF: Don't oversize COMMON symbols when targeting BFD ld
COFF normally doesn't allow us to describe the alignment of COMMON
symbols.

It turns out that most linkers use the symbol size as a hint as to how
aligned the symbol should be.

However the BFD folks have added a .drectve command, which we
now support as of r219229, that allows us to specify the alignment
precisely.  With this in mind, stop rounding sizes up.

llvm-svn: 219281
2014-10-08 06:38:53 +00:00
Saleem Abdulrasool 64d491e488 MC: add support for -aligncomm GNU extension
The GNU linker supports an -aligncomm directive that allows for power-of-2
alignment of common data.  Add support to emit this directive.

llvm-svn: 219229
2014-10-07 19:37:57 +00:00
Yuri Gorshenin e8c81fd25a [asan-asm-instrumentation] CFI directives are generated for .S files.
Summary: CFI directives are generated for .S files.

Reviewers: eugenis

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D5520

llvm-svn: 219199
2014-10-07 11:03:09 +00:00
Hans Wennborg 1b1a399489 MachObjectWriter: optimize the string table for common suffices
This is a follow-up to r207670 (ELF) and r218636 (COFF).

Differential Revision: http://reviews.llvm.org/D5622

llvm-svn: 219126
2014-10-06 17:05:19 +00:00
Rafael Espindola 11527a1d71 Note that a gold bug has been fixed.
We should be able to stop working around it at some point in the future.

llvm-svn: 219115
2014-10-06 12:33:27 +00:00
Benjamin Kramer cb3e06ba00 MCParser: Modernize memory handling.
NFC.

llvm-svn: 218998
2014-10-03 18:32:55 +00:00
Daniel Sanders ef638fea2d [mips] Print warning when using register names not available in N32/64
Summary:
The register names t4-t7 are not available in the N32 and N64 ABIs.
This patch prints a warning, when those names are used in N32/64,
along with a fix-it with the correct register names.

Patch by Vasileios Kalintiris

Reviewers: dsanders

Reviewed By: dsanders

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D5272

llvm-svn: 218989
2014-10-03 15:37:37 +00:00
Bradley Smith 7a77075530 Extend C disassembler API to allow specifying target features
llvm-svn: 218682
2014-09-30 16:31:40 +00:00
Hans Wennborg f26bfc1671 WinCOFFObjectWriter: optimize the string table for common suffices
This is a follow-up from r207670 which did the same for ELF.

Differential Revision: http://reviews.llvm.org/D5530

llvm-svn: 218636
2014-09-29 22:43:20 +00:00
Hans Wennborg ba80b5d43c WinCOFFObjectWriter.cpp: make write_uint32_le more efficient
llvm-svn: 218574
2014-09-28 00:22:27 +00:00
Reid Kleckner 81782f0cb8 MC: Use @IMGREL instead of @IMGREL32, which we can't parse
Nico Rieck added support for this 32-bit COFF relocation some time ago
for Win64 stuff. It appears that as an oversight, the assembly output
used "foo"@IMGREL32 instead of "foo"@IMGREL, which is what we can parse.

Sadly, there were actually tests that took in IMGREL and put out
IMGREL32, and we didn't notice the inconsistency. Oh well. Now LLVM can
assemble it's own output with slightly more fidelity.

llvm-svn: 218437
2014-09-25 02:09:18 +00:00
Akira Hatanaka 8e77dbbf5a Revert r218380. This was breaking Apple internal build bots.
llvm-svn: 218409
2014-09-24 20:37:14 +00:00
Benjamin Kramer ce246a13ea Replace a hand-written suffix compare with std::lexicographical_compare.
No functionality change.

llvm-svn: 218380
2014-09-24 13:19:28 +00:00
Oliver Stannard 14f97d0017 Downgrade DWARF2 section limit error to a warning
We currently emit an error when trying to assemble a file with more
than one section using DWARF2 debug info. This should be a warning
instead, as the resulting file will still be usable, but with a
degraded debug illusion.

llvm-svn: 218241
2014-09-22 10:45:16 +00:00
Ehsan Akhgari db0e7061c6 ms-inline-asm: Add a sema callback for looking up label names
The implementation of the callback in clang's Sema will return an
internal name for labels.

Test Plan: Will be tested in clang.

Reviewers: rnk

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D4587

llvm-svn: 218229
2014-09-22 02:21:35 +00:00
David Majnemer 48227a3759 MC: Support aligned COMMON symbols for COFF
link.exe:
Fuzz testing has shown that COMMON symbols with size > 32 will always
have an alignment of at least 32 and all symbols with size < 32 will
have an alignment of at least the largest power of 2 less than the size
of the symbol.

binutils:
The BFD linker essentially work like the link.exe behavior but with
alignment 4 instead of 32.  The BFD linker also supports an extension to
COFF which adds an -aligncomm argument to the .drectve section which
permits specifying a precise alignment for a variable but MC currently
doesn't support editing .drectve in this way.

With all of this in mind, we decide to play a little trick: we can
ensure that the alignment will be respected by bumping the size of the
global to it's alignment.

llvm-svn: 218201
2014-09-21 09:18:07 +00:00
David Majnemer 7d0dc3ef18 MC: Fix MCSectionCOFF::PrintSwitchToSection
We had a few bugs:
- We were considering the GVKind instead of just looking at the section
  characteristics
- We would never print out 'y' when a section was meant to be unreadable
- We would never print out 's' when a section was meant to be shared
- We translated IMAGE_SCN_MEM_DISCARDABLE to 'n' when it should've meant
  IMAGE_SCN_LNK_REMOVE

llvm-svn: 218189
2014-09-20 20:40:50 +00:00
David Majnemer b8dbebb31c MC: Treat ReadOnlyWithRel and ReadOnlyWithRelLocal as ReadOnly for COFF
A problem with our old behavior becomes observable under x86-64 COFF
when we need a read-only GV which has an initializer which is referenced
using a relocation: we would mark the section as writable.  Marking the
section as writable interferes with section merging.

This fixes PR21009.

llvm-svn: 218179
2014-09-20 07:31:46 +00:00
Benjamin Kramer 04f9da8f21 Elide unnecessary DenseMap copy.
No functionality change.

llvm-svn: 218122
2014-09-19 12:26:38 +00:00
Yaron Keren d122211e60 Another required re-setting for MCStreamer::reset().
llvm-svn: 217970
2014-09-17 17:50:34 +00:00