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
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
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
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
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
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
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
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
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
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
Teach WinCOFFObjectWriter how to write -mbig-obj style object files;
these object files allow for more sections inside an object file.
Our support for BigObj is notably different from binutils and cl: we
implicitly upgrade object files to BigObj instead of asking the user to
compile the same file *again* but with another flag. This matches up
with how LLVM treats ELF variants.
This was tested by forcing LLVM to always emit BigObj files and running
the entire test suite. A specific test has also been added.
I've lowered the maximum number of sections in a normal COFF file,
VS "14" CTP 3 supports no more than 65279 sections. This is important
otherwise we might not switch to BigObj quickly enough, leaving us with
a COFF file that we couldn't link.
yaml2obj support is all that remains to implement.
Differential Revision: http://reviews.llvm.org/D5349
llvm-svn: 217812
This adds support for reading the "bigobj" variant of COFF produced by
cl's /bigobj and mingw's -mbig-obj.
The most significant difference that bigobj brings is more than 2**16
sections to COFF.
bigobj brings a few interesting differences with it:
- It doesn't have a Characteristics field in the file header.
- It doesn't have a SizeOfOptionalHeader field in the file header (it's
only used in executable files).
- Auxiliary symbol records have the same width as a symbol table entry.
Since symbol table entries are bigger, so are auxiliary symbol
records.
Write support will come soon.
Differential Revision: http://reviews.llvm.org/D5259
llvm-svn: 217496
DWARF address ranges contain a reference to the debug_info section. This offset
is an absolute relocation except on non-PE/COFF targets where it is section
relative. We would emit this incorrectly, and trying to map the debug info from
the address would fail.
llvm-svn: 217317
The header contains an offset to the DWARF line table for the CU. The offset
must be section relative for COFF and absolute for others. The non-assembly
code path for the DWARF header generation already has the correct emission for
the headers. This corrects the assembly input path.
This was identified by BFD objecting to the LLVM generated DWARF information.
llvm-svn: 217222
Summary:
This fixes a long standing issue where we would emit many little .text
sections and only one .pdata and .xdata section. Now we generate one
.pdata / .xdata pair per .text section and associate them correctly.
Fixes PR19667.
Reviewers: majnemer
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D5181
llvm-svn: 217176
The code is buggy and barely tested. It is also mostly boilerplate.
(This includes MCObjectDisassembler, which is the interface to that
functionality)
Following an IRC discussion with Jim Grosbach, it seems sensible to just
nuke the whole lot of functionality, and dig it up from VCS if
necessary (I hope not!).
All of this stuff appears to have been added in a huge patch dump (look
at the timeframe surrounding e.g. r182628) where almost every patch
seemed to be untested and not reviewed before being committed.
Post-review responses to the patches were never addressed. I don't think
any of it would have passed pre-commit review.
I doubt anyone is depending on this, since this code appears to be
extremely buggy. In limited testing that Michael Spencer and I did, we
couldn't find a single real-world object file that wouldn't crash the
CFG reconstruction stuff. The symbolizer stuff has O(n^2) behavior and
so is not much use to anyone anyway. It seemed simpler to remove them as
a whole. Most of this code is boilerplate, which is the only way it was
able to scrape by 60% coverage.
HEADSUP: Modules folks, some files I nuked were referenced from
include/llvm/module.modulemap; I just deleted the references. Hopefully
that is the right fix (one was a FIXME though!).
llvm-svn: 216983
This removes static initializers from the backends which generate this data, and also makes this struct match the other Tablegen generated structs in behaviour
Reviewed by Andy Trick and Chandler C
llvm-svn: 216919
This is an enum class, and will be appropriately prefixed, making the encoding
type prefix redundant. No change to any uses as the use of this was not yet
introduced.
llvm-svn: 216893
Take a StringRef instead of a "const char *".
Take a "std::error_code &" instead of a "std::string &" for error.
A create static method would be even better, but this patch is already a bit too
big.
llvm-svn: 216393
It makes no sense and can hide bugs. In particular, it lead
to left shift by 64 bits, which is an undefined behavior,
properly reported by UBSan.
llvm-svn: 216134
ARM in particular is getting dangerously close to exceeding 32 bits worth of
possible subtarget features. When this happens, various parts of MC start to
fail inexplicably as masks get truncated to "unsigned".
Mostly just refactoring at present, and there's probably no way to test.
llvm-svn: 215887
As X86MCAsmInfoDarwin uses '##' as CommentString although a single '#' starts a
comment a workaround for this special case is added.
Fixes divisions in constant expressions for the AArch64 assembler and other
targets which use '//' as CommentString.
Patch by Janne Grunau!
llvm-svn: 215615
Add header guards to files that were missing guards. Remove #endif comments
as they don't seem common in LLVM (we can easily add them back if we decide
they're useful)
Changes made by clang-tidy with minor tweaks.
llvm-svn: 215558
This removes the duplicate definition of GetXDataSection. This function is
available as a static method and is identical to the previous implementation.
This just cleans up the unnecessary duplication.
llvm-svn: 215289
This changes Win64EHEmitter into a utility WinEH UnwindEmitter that can be
shared across multiple architectures and a target specific bit which is
overridden (Win64::UnwindEmitter). This enables sharing the section selection
code across X86 and the intended use in ARM for emitting unwind information for
Windows on ARM.
llvm-svn: 215050
Duplicate the vararg tests for linux and add a tests which mixed
vararg arguments with darwin positional parameters.
Patch by: Janne Grunau <j@jannau.net>
llvm-svn: 214799
This makes EmitWindowsUnwindTables a virtual function and lowers the
implementation of the function to the X86WinCOFFStreamer. This method is a
target specific operation. This enables making the behaviour target dependent
by isolating it entirely to the target specific streamer.
llvm-svn: 214664
The frame information stored in this structure is driven by the requirements for
Windows NT unwinding rather than Windows 64 specifically. As a result, this
type can be shared across multiple architectures (ARM, AXP, MIPS, PPC, SH).
Rename this class in preparation for adding support for supporting unwinding
information for Windows on ARM.
Take the opportunity to constify the members as everything except the
ChainedParent is read-only. This required some adjustment to the label
handling.
llvm-svn: 214663
This patch adds code to emits the StackMap section on ELF systems. This section is required to support llvm.experimental.stackmap and llvm.experimental.patchpoint intrinsics.
Reviewers: ributzka, echristo
Differential Revision: http://reviews.llvm.org/D4574
llvm-svn: 214538
This recommits r208930, r208933, and r208975 (by reverting r209338) and
reverts r209529 (the FIXME to readd this functionality once the tools
were fixed) now that DWP has been fixed to cope with a single section
for all fission type units.
Original commit message:
"Since type units in the dwo file are handled by a debug aware tool,
they don't need to leverage the ELF comdat grouping to implement
deduplication. Avoid creating all the .group sections for these as a
space optimization."
llvm-svn: 213956
There were still some disassembler bits in lib/MC, but their use of Object
was only visible in the includes they used, not in the symbols.
llvm-svn: 213808
Having both Triple::arm64 and Triple::aarch64 is extremely confusing, and
invites bugs where only one is checked. In reality, the only legitimate
difference between the two (arm64 usually means iOS) is also present in the OS
part of the triple and that's what should be checked.
We still parse the "arm64" triple, just canonicalise it to Triple::aarch64, so
there aren't any LLVM-side test changes.
llvm-svn: 213743
As discussed in a previous checking to support the .localentry
directive on PowerPC, we need to inspect the actual target symbol
in needsRelocateWithSymbol to make the appropriate decision based
on that symbol's st_other bits.
Currently, needsRelocateWithSymbol does not get the target symbol.
However, it is directly available to its sole caller. This patch
therefore simply extends the needsRelocateWithSymbol by a new
parameter "const MCSymbolData &SD", passes in the target symbol,
and updates all derived implementations.
In particular, in the PowerPC implementation, this patch removes
the FIXME added by the previous checkin.
llvm-svn: 213487
This adds an optional parameter to the EmitSymbolValue method in MCStreamer to
permit emitting a symbol value as a section relative value. This is to cover
the use in MCDwarf which should not really know about how to emit a section
relative value for a given target.
This addresses post-review comments from Eric Christopher in SVN r213275.
llvm-svn: 213463
On AArch64 the pseudo instruction ldr <reg>, =... supports both
32-bit and 64-bit constants. Add support for 64 bit constants for
the pools to support the pseudo instruction fully.
Changes the AArch64 ldr-pseudo tests to use 32-bit registers and
adds tests with 64-bit registers.
Patch by Janne Grunau!
Differential Revision: http://reviews.llvm.org/D4279
llvm-svn: 213387
The header contains an offset to the DWARF abbreviations for the CU. The offset
must be section relative for COFF and absolute for others. The non-assembly
code path for the DWARF header generation already had the correct emission for
the headers. This corrects just the assembly path. Due to the invalid
relocation, processing of the debug information would halt previously on the
first assembly input as the associated abbreviations would be out of range as
they would have the location increased by image base and the section offset.
This address PR20332.
llvm-svn: 213275
Rather than use three EmitBytes, concatenate the string at compile time,
constructing a single StringRef and emitting the data in one shot. This also
creates nicer assembly output. NFC.
llvm-svn: 213273
This makes the opcode an opaque value (unsigned int) rather than the
enumeration. This permits the use of target specific operands.
Split out the generic type into a MCWinEH header and add a supporting
MCWin64EH::Instruction to abstract out the selection of the opcode and
construction of the actual instruction.
llvm-svn: 213221
COFF lacks a feature that other object file formats support: mergeable
sections.
To work around this, MSVC sticks constant pool entries in special COMDAT
sections so that each constant is in it's own section. This permits
unused constants to be dropped and it also allows duplicate constants in
different translation units to get merged together.
This fixes PR20262.
Differential Revision: http://reviews.llvm.org/D4482
llvm-svn: 213006
This is the first of a number of changes designed to generalise
MCWin64EHInstruction to support different target architectures. An ordered set
(vector) of these instructions is saved per frame to permit the emission of
information for Windows NT style unwinding. The only bit of information which
is actually target specific here is the Opcode for the unwinding bytecode. The
remainder of the information is simply generic information that is relevant to
the Windows NT unwinding model.
Remove the accessors for the fields, making them const and public instead. Sink
the knowledge of the alias'ed name into the single source and sink a single-use
check method into the use.
llvm-svn: 212914
Rename member variables and functions for the MCStreamer for DWARF-like
unwinding management. Rename the Windows ones as well and make the naming and
handling similar across the two. No functional change intended.
llvm-svn: 212912
MC was aping a binutils bug where aliases would default their linkage to
private instead of internal.
I've sent a patch to the binutils maintainers and they've recently
applied it to the GNU assembler sources.
This fixes PR20152.
Differential Revision: http://reviews.llvm.org/D4395
llvm-svn: 212899
Due to the fact that the windows unwinding has the concept of chained frames, we
maintain a current frame info pointer that is adjusted on any push and pop of a
unwinding context. This just removes an unnecessary variable that was used to
mirror the DWARF unwinding code.
llvm-svn: 212882