Correct the section flags for code built for Windows on ARM with
`-ffunction-sections`. Windows on ARM uses solely Thumb-2 instructions, and
indicates that the function is thumb by placing it in a text section that has
IMAGE_SCN_MEM_16BIT flag set.
When we encounter a .section directive, a new section is constructed. This may
be a text segment. In order to identify that we need the additional flag,
expose the target triple through the ObjectFileInfo as this information is lost
otherwise.
Since any modern ARM targeting environment on Windows would be Thumb-2 (Windows
ARM NT or Windows Embedded Compact), introducing a new flag to indicate the
section attribute seems to be a bit overkill. Simply depend on the target
triple. Since there is one location that this information is currently needed,
creating a target specific assembly parser and delegating the parsing of section
switches also feels a bit heavy handed. If it turns out that this information
ends up changing additional behaviour, then it may be worth considering that
alternative.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211481 91177308-0d34-0410-b5e6-96231b3b80d8
This patch enables LLVM to emit Win64-native unwind info rather than
DWARF CFI. It handles all corner cases (I hope), including stack
realignment.
Because the unwind info is not flexible enough to describe stack frames
with a gap of unknown size in the middle, such as the one caused by
stack realignment, I modified register spilling code to place all spills
into the fixed frame slots, so that they can be accessed relative to the
frame pointer.
Patch by Vadim Chugunov!
Reviewed By: rnk
Differential Revision: http://reviews.llvm.org/D4081
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211399 91177308-0d34-0410-b5e6-96231b3b80d8
Currently, when using llvm as an assembler, DWARF debug information is only
generated for the .text section. This patch modifies this so that DWARF info
is emitted for all executable sections.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211273 91177308-0d34-0410-b5e6-96231b3b80d8
used by all of the MC level tools and codegen. Fix up all uses
in the compiler to use this and set it on the context accordingly.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211257 91177308-0d34-0410-b5e6-96231b3b80d8
ARMTargetStreamer implements ConstantPool and AssmeblerConstantPools
to keep track of assembler-generated constant pools that are used for
ldr-pseudo.
When implementing ldr-pseudo for AArch64, these two classes can be reused.
So this patch factors them out from ARM target to the general MC lib.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211198 91177308-0d34-0410-b5e6-96231b3b80d8
Most Windows platforms use auxiliary data for unwinding. This information is
stored in the .pdata section. The encoding format for the data differs between
architectures and Windows variants. Windows MIPS and Alpha use identical
formats; Alpha64 is the same with different widths. Windows x86_64 and Itanium
share the representation. All Windows CE entries are identical irrespective of
the architecture. ARMv7 (Windows [NT] on ARM) has its own format.
This enumeration will become the differentiator once the windows EH emission
infrastructure is generalised, allowing us to emit the necessary unwinding
information for Windows on ARM.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210634 91177308-0d34-0410-b5e6-96231b3b80d8
I saw at least a memory leak or two from inspection (on probably
untested error paths) and r206991, which was the original inspiration
for this change.
I ran this idea by Jim Grosbach a few weeks ago & he was OK with it.
Since it's a basically mechanical patch that seemed sufficient - usual
post-commit review, revert, etc, as needed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210427 91177308-0d34-0410-b5e6-96231b3b80d8
* Section association cannot use just the section name as many
sections can have the same name. With this patch, the comdat symbol in
an assoc section is interpreted to mean a symbol in the associated
section and the mapping is discovered from it.
* Comdat symbols were not being set correctly. Instead we were getting
whatever was output first for that section.
A consequence is that associative sections now must use .section to
set the association. Using .linkonce would not work since it is not
possible to change a sections comdat symbol (it is used to decide if
we should create a new section or reuse an existing one).
This includes r210298, which was reverted because it was asserting
on an associated section having the same comdat as the associated
section.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210367 91177308-0d34-0410-b5e6-96231b3b80d8
We extended the .section syntax to allow multiple sections with the
same name but different comdats, but currently we don't make sure that
the output section has that comdat symbol.
That happens to work with the code llc produces currently because it looks like
.section secName, "dr", one_only, "COMDATSym"
.globl COMDATSym
COMDATSym:
....
but that is not very friendly to anyone coding in assembly or even to
llc once we get comdat support in the IR.
This patch changes the coff object writer to make sure the comdat symbol is
output just after the section symbol, as required by the coff spec.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210298 91177308-0d34-0410-b5e6-96231b3b80d8
This makes LLVM create N_INDR aliases (to be resolved by the linker) when
appropriate.
rdar://problem/15125513
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@209894 91177308-0d34-0410-b5e6-96231b3b80d8
Now that clang can be used as an assembler via the IAS, invalid assembler inputs
would cause the assertions to trigger. Although we cannot recover from the
errors here, nor provide caret diagnostics, attempt to handle them slightly more
gracefully by reporting a fatal error.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@209387 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit r208930, r208933, and r208975.
It seems not all fission consumers are ready to handle this behavior.
Reverting until tools are brought up to spec.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@209338 91177308-0d34-0410-b5e6-96231b3b80d8
Add support to allow a target specific COFF object writer to restrict the
recorded resolutions in the emitted object files. This is motivated by the need
in Windows on ARM, where an intermediate relocation needs to be prevented from
being emitted in the object file.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@209336 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208930 91177308-0d34-0410-b5e6-96231b3b80d8
The old method used by X86TTI to determine partial-unrolling thresholds was
messy (because it worked by testing target features), and also would not
correctly identify the target CPU if certain target features were disabled.
After some discussions on IRC with Chandler et al., it was decided that the
processor scheduling models were the right containers for this information
(because it is often tied to special uop dispatch-buffer sizes).
This does represent a small functionality change:
- For generic x86-64 (which uses the SB model and, thus, will get some
unrolling).
- For AMD cores (because they still currently use the SB scheduling model)
- For Haswell (based on benchmarking by Louis Gerbarg, it was decided to bump
the default threshold to 50; we're working on a test case for this).
Otherwise, nothing has changed for any other targets. The logic, however, has
been moved into BasicTTI, so other targets may now also opt-in to this
functionality simply by setting LoopMicroOpBufferSize in their processor
model definitions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208289 91177308-0d34-0410-b5e6-96231b3b80d8
This removes arguments passed everywhere and allows the use of
standard iteration over lists.
Should be no functional change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208127 91177308-0d34-0410-b5e6-96231b3b80d8
The fix itself is fairly simple: move getAccessVariant to MCValue so that we
replace the old weak expression evaluation with the far more general
EvaluateAsRelocatable.
This then requires that EvaluateAsRelocatable stop when it finds a non
trivial reference kind. And that in turn requires the ELF writer to look
harder for weak references.
Last but not least, this found a case where we were being bug by bug
compatible with gas and accepting an invalid input. I reported pr19647
to track it.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207920 91177308-0d34-0410-b5e6-96231b3b80d8
This simplifies ELFObjectWriter::SymbolValue a bit more. This new version
will also be used in the COFF writer to fix pr19147.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207711 91177308-0d34-0410-b5e6-96231b3b80d8
