Before when deciding if we needed a relocation in A-B, we wore only checking
if A was weak.
This fixes the asymmetry.
The "InSet" argument should probably be renamed to "ForValue", since InSet is
very MachO specific, but doing so in this patch would make it hard to read.
This fixes PR22815.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234165 91177308-0d34-0410-b5e6-96231b3b80d8
Just store the section in MCSectionELF. This avoids multiple hash lookups.
This will also be used by ARM_EXIDX.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234139 91177308-0d34-0410-b5e6-96231b3b80d8
This allows the compiler/assembly programmer to switch back to a
section. This in turn fixes the bootstrap failure on powerpc (tested
on gcc110) without changing the ppc codegen at all.
I will try to cleanup the various getELFSection overloads in a followup patch.
Just using a default argument now would lead to ambiguities.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234099 91177308-0d34-0410-b5e6-96231b3b80d8
Fixes PR19582.
Previously, when an asm assignment (.set or =) was created, we would look up
the section immediately in MCSymbol::setVariableValue. This caused symbols
to receive the wrong section if the RHS of the assignment had not been seen
yet. This had a knock-on effect in the object file emitters, causing them
to emit extra symbols, or to give symbols the wrong visibility or the wrong
section. For example, in the following asm:
.data
.Llocal:
.text
leaq .Llocal1(%rip), %rdi
.Llocal1 = .Llocal2
.Llocal2 = .Llocal
the first assignment would give .Llocal1 a null section, which would never get
fixed up by the second assignment. This would cause the ELF object file emitter
to consider .Llocal1 to be an undefined symbol and give it external linkage,
even though .Llocal1 should not have been emitted at all in the object file.
Or in the following asm:
alias_to_local = Ltmp0
Ltmp0:
the Mach-O object file emitter would give the alias_to_local symbol a n_type
of N_SECT and a n_sect of 0. This is invalid under the Mach-O specification,
which requires N_SECT symbols to receive a non-zero section number if the
symbol is defined in a section in the object file.
https://developer.apple.com/library/mac/documentation/DeveloperTools/Conceptual/MachORuntime/#//apple_ref/c/tag/nlist
After this change we do not look up the section when the assignment is created,
but instead look it up on demand and store it in Section, which is treated
as a cache if the symbol is a variable symbol.
This change also fixes a bug in MCExpr::FindAssociatedSection. Previously,
if we saw a subtraction, we would return the first referenced section, even in
cases where we should have been returning the absolute pseudo-section. Now we
always return the absolute pseudo-section for expressions that subtract two
section-derived expressions. This isn't always correct (e.g. if one of the
sections ends up being laid out at an absolute address), but it's probably
the best we can do without more context.
This allows us to remove code in two places where we appear to have been
working around this bug, in MachObjectWriter::markAbsoluteVariableSymbols
and in X86AsmPrinter::EmitStartOfAsmFile.
Re-applies r233595 (aka D8586), which was reverted in r233898.
Differential Revision: http://reviews.llvm.org/D8798
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233995 91177308-0d34-0410-b5e6-96231b3b80d8
This lets us catch exceptions in simple cases.
N.B. Things that do not work include (but are not limited to):
- Throwing from within a catch handler.
- Catching an object with a named catch parameter.
- 'CatchHigh' is fictitious, we aren't sure of its purpose.
- We aren't entirely efficient with regards to the number of EH states
that we generate.
- IP-to-State tables are sensitive to the order of emission.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233767 91177308-0d34-0410-b5e6-96231b3b80d8
This is necessary for x86 where not all Sandybridge, Ivybrige, Haswell, and Broadwell CPUs support AVX. Currently we modify the CPU name back to Nehalem for this case, but that turns off additional features for these CPUs.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233673 91177308-0d34-0410-b5e6-96231b3b80d8
These sections are never looked up and we know when have to create them. Use
that to save adding them to the regular map and avoid a symbol->string->symbol
conversion for the group symbol.
This also makes the implementation independent of the details of how unique
sections are implemented.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233539 91177308-0d34-0410-b5e6-96231b3b80d8
All the ports have been fixed to read the feature bits from the subtarget passed
to the print methods. Also, delete the call to setAvailableFeatures in the
constructor of NVPTX's instprinter as the instprinter wasn't using the feature
bits anywhere.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233486 91177308-0d34-0410-b5e6-96231b3b80d8
per-function subtarget.
Currently, code-gen passes the default or generic subtarget to the constructors
of MCInstPrinter subclasses (see LLVMTargetMachine::addPassesToEmitFile), which
enables some targets (AArch64, ARM, and X86) to change their instprinter's
behavior based on the subtarget feature bits. Since the backend can now use
different subtargets for each function, instprinter has to be changed to use the
per-function subtarget rather than the default subtarget.
This patch takes the first step towards enabling instprinter to change its
behavior based on the per-function subtarget. It adds a bit "PassSubtarget" to
AsmWriter which tells table-gen to pass a reference to MCSubtargetInfo to the
various print methods table-gen auto-generates.
I will follow up with changes to instprinters of AArch64, ARM, and X86.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233411 91177308-0d34-0410-b5e6-96231b3b80d8
There is something in link.exe that requires a relocation to use a
global symbol. Not doing so breaks the chrome build on windows.
This patch sets isWeak for that to work. To compensate,
we then need to look past those symbols when not creating relocations.
This patch includes an ELF test that matches GNU as behaviour.
I am still reducing the chrome build issue and will add a test
once that is done.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233318 91177308-0d34-0410-b5e6-96231b3b80d8
The previous logic was to first try without relocations at all
and failing that stop on the first defined symbol.
That was inefficient and incorrect in the case part of the
expression could be simplified and another part could not
(see included test).
We now stop the evaluation when we get to a variable whose value
can change (i.e. is weak).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233187 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit r233055.
It still causes buildbot failures (gcc running out of memory on several platforms, and a self-host failure on arm), although less than the previous time.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233068 91177308-0d34-0410-b5e6-96231b3b80d8
Previously, subtarget features were a bitfield with the underlying type being uint64_t.
Since several targets (X86 and ARM, in particular) have hit or were very close to hitting this bound, switching the features to use a bitset.
No functional change.
The first time this was committed (r229831), it caused several buildbot failures.
At least some of the ARM ones were due to gcc/binutils issues, and should now be fixed.
Differential Revision: http://reviews.llvm.org/D8542
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233055 91177308-0d34-0410-b5e6-96231b3b80d8
There is now a canonical symbol at the end of a section that different
passes can request.
This also allows us to assert that we don't switch back to a section whose
end symbol has already been printed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233026 91177308-0d34-0410-b5e6-96231b3b80d8
The code this patch removes was there to make sure the text sections went
before the dwarf sections. That is necessary because MachO uses offsets
relative to the start of the file, so adding a section can change relaxations.
The dwarf sections were being printed at the start just to produce symbols
pointing at the start of those sections.
The underlying issue was fixed in r231898. The dwarf sections are now printed
when they are about to be used, which is after we printed the text sections.
To make sure we don't regress, the patch makes the MachO streamer assert
if CodeGen puts anything unexpected after the DWARF sections.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@232842 91177308-0d34-0410-b5e6-96231b3b80d8
There are two main advantages to doing this
* Targets that only need to handle one of the formats specially don't have
to worry about the others. For example, x86 now only registers a
constructor for the COFF streamer.
* Changes to the arguments passed to one format constructor will not impact
the other formats.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@232699 91177308-0d34-0410-b5e6-96231b3b80d8
Before this patch code wanting to create temporary labels for a given entity
(function, cu, exception range, etc) had to keep its own counter to have stable
symbol names.
createTempSymbol would still add a suffix to make sure a new symbol was always
returned, but it kept a single counter. Because of that, if we were to use
just createTempSymbol("cu_begin"), the label could change from cu_begin42 to
cu_begin43 because some other code started using temporary labels.
Simplify this by just keeping one counter per prefix and removing the various
specialized counters.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@232535 91177308-0d34-0410-b5e6-96231b3b80d8
Same as MakeArgString in r232465, keep only LookupSymbol(Twine)
while making sure it handles the StringRef like cases efficiently
using twine::toStringRef.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@232517 91177308-0d34-0410-b5e6-96231b3b80d8
This covers essentially all of llvm's headers and libs. One or two weird
cases I wasn't sure were worth/appropriate to fix.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@232394 91177308-0d34-0410-b5e6-96231b3b80d8
This lets us pass the symbol to the constructor and avoid the mutable field.
This also opens the way for outputting the symbol only when needed, instead
of outputting them at the start of the file.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@231859 91177308-0d34-0410-b5e6-96231b3b80d8
This makes code that uses section relative expressions (debug info) simpler and
less brittle.
This is still a bit awkward as the symbol is created late and has to be
stored in a mutable field.
I will move the symbol creation earlier in the next patch.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@231802 91177308-0d34-0410-b5e6-96231b3b80d8
When referring to a symbol in a dwarf section on ELF we should use
.long foo
instead of
.long foo - .debug_something
because ELF is unaware of the content of the sections and therefore needs
relocations. This has nothing to do with optimizing a -0.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@231751 91177308-0d34-0410-b5e6-96231b3b80d8
They mark the start of a compile unit, so name them .Lcu_*. Using
Section->getLabelBeginName() makes it looks like they mark the start of the
section.
While at it, switch to createTempSymbol to avoid collisions with labels
created in inline assembly. Not sure if a "don't crash" test is worth it.
With this getLabelBeginName is dead, delete it.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@231750 91177308-0d34-0410-b5e6-96231b3b80d8
CloudABI is a POSIX-like runtime environment built around the concept of
capability-based security. More details:
https://github.com/NuxiNL/cloudlibc
CloudABI uses its own ELFOSABI number. This number has been allocated by
the maintainers of ELF a couple of days ago.
Reviewed by: echristo
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@231681 91177308-0d34-0410-b5e6-96231b3b80d8
Accidentally committed a few more of these cleanup changes than
intended. Still breaking these out & tidying them up.
This reverts commit r231135.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@231136 91177308-0d34-0410-b5e6-96231b3b80d8
There doesn't seem to be any need to assert that iterator assignment is
between iterators over the same node - if you want to reuse an iterator
variable to iterate another node, that's perfectly acceptable. Just
don't mix comparisons between iterators into disjoint sequences, as
usual.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@231135 91177308-0d34-0410-b5e6-96231b3b80d8
This removes a bit of duplicated code and more importantly, remembers the
labels so that they don't need to be looked up by name.
This in turn allows for any name to be used and avoids a crash if the name
we wanted was already taken.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230772 91177308-0d34-0410-b5e6-96231b3b80d8
