This starts merging MCSection and MCSectionData.
There are a few issues with the current split between MCSection and
MCSectionData.
* It optimizes the the not as important case. We want the production
of .o files to be really fast, but the split puts the information used
for .o emission in a separate data structure.
* The ELF/COFF/MachO hierarchy is not represented in MCSectionData,
leading to some ad-hoc ways to represent the various flags.
* It makes it harder to remember where each item is.
The attached patch starts merging the two by moving the alignment from
MCSectionData to MCSection.
Most of the patch is actually just dropping 'const', since
MCSectionData is mutable, but MCSection was not.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237936 91177308-0d34-0410-b5e6-96231b3b80d8
Create a low-overhead path for `EmitLabelDifference()` that emits a
emits an absolute number when (1) the output is an object stream and (2)
the two symbols are in the same data fragment.
This drops memory usage on Mach-O from 975 MB down to 919 MB (5.8%).
The only call is when `!doesDwarfUseRelocationsAcrossSections()` --
i.e., on Mach-O -- since otherwise an absolute offset from the start of
the section needs a relocation. (`EmitLabelDifference()` is cheaper on
ELF anyway, since it creates 1 fewer temp symbol, and it gets called far
less often. It's not clear to me if this is even a bottleneck there.)
(I'm looking at `llc` memory usage on `verify-uselistorder.lto.opt.bc`;
see r236629 for details.)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237876 91177308-0d34-0410-b5e6-96231b3b80d8
Finally remove the `MCSymbolData::Symbol` pointer. It was still being
used to track whether `MCSymbolData` had been initialized, but this is
better tracked by the bitfield in `MCSymbol`.
The only caller of `MCSymbolData::initialize()` was `MCAssembler`, which
(other than `Symbol`) passed in all-0 values. Replace all that
indirection with a default constructor.
The main point is a cleanup (and there's more cleanup to do), but there
are also some small memory savings. I measured ~989 MB down to ~975 MB,
cutting a little over 1% off the top of `llc`.
(I'm looking at `llc` memory usage on `verify-uselistorder.lto.opt.bc`;
see r236629 for details.)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237873 91177308-0d34-0410-b5e6-96231b3b80d8
Remove the last use of `MCSymbolData::getSymbol()`. There's some
*really* hairy stuff going on in `MachObjectWriter::WriteNList()` that I
want to come back to. In particular, it updates `Symbol` to point at
its aliasee (if any), but leaves `Data` behind, and it's not clear
whether everything makes sense there.
For now I've left the logic unchanged by adding `OrigSymbol` and moving
the FIXME from r237750 up a bit higher. I've filed PR23598 to track
looking into this.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237867 91177308-0d34-0410-b5e6-96231b3b80d8
Remove most remaining calls to `MCSymbolData::getSymbol()`, instead
using the already available `MCSymbol` directly.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237829 91177308-0d34-0410-b5e6-96231b3b80d8
This code appends the filename to the directory then looks that up in a StringMap. We should be using the existing Twine::toStringRef method instead of Twine::str() as most times we'll succeed in the lookup.
Its possible that we should also consider allowing StringMap to lookup a key using a Twine in addition to a StringRef but that would complicate the code with little known benefit above and beyond this change.
This saves 170k temporary allocations when running llc on the verify_use_list_order bitcode with debug info for x86.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237823 91177308-0d34-0410-b5e6-96231b3b80d8
r237490 accidentally dropped MCSymbolData from the MCAssembler dump.
Add it back underneath the MCSymbol dump. Remove the MCSymbol dump from
MCSymbolData, since this would cause an infinite co-recursion, and
besides, that back pointer is going away.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237807 91177308-0d34-0410-b5e6-96231b3b80d8
Replace uses of `MCSymbolData` with `MCSymbol` where both are needed, so
we can remove the backpointer.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237799 91177308-0d34-0410-b5e6-96231b3b80d8
Transition one API from `MCSymbolData` to `MCSymbol`. The function
needs both, and the backpointer from `MCSymbolData` to `MCSymbol` is
going away.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237498 91177308-0d34-0410-b5e6-96231b3b80d8
Change `MCFragment::Atom` from an `MCSymbolData` to an `MCSymbol`,
moving in the direction of removing the back-pointer.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237497 91177308-0d34-0410-b5e6-96231b3b80d8
Instead of storing a list of the `MCSymbolData` in use, store the
`MCSymbol`s. Churning in the direction of removing the back pointer
from `MCSymbolData`.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237496 91177308-0d34-0410-b5e6-96231b3b80d8
Turn `MCSymbolData` into a field inside of `MCSymbol`. Keep all the old
API alive for now, so that consumers can be updated in a later commit.
This means we still temporarily need the back pointer from
`MCSymbolData` to `MCSymbol`, but I'll remove it in a follow-up.
This optimizes for object emission over assembly emission. By removing
the `DenseMap` in `MCAssembler`, llc memory usage drops from around 1040
MB to 1001 MB (3.8%).
(I'm looking at `llc` memory usage on `verify-uselistorder.lto.opt.bc`;
see r236629 for details.)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237490 91177308-0d34-0410-b5e6-96231b3b80d8
Stop exposing the storage for `MCAssembler::Symbols`, and have
`MCAssembler` add symbols directly to its list instead of using a hook
in `MCSymbolData`. This opens up room for a follow-up commit to switch
from a linked list to a vector.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237486 91177308-0d34-0410-b5e6-96231b3b80d8
MCInstrDesc.h includes things like MCInst.h which i can now remove after this. That will be a future commit.
Reviewed by Jim Grosbach.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237478 91177308-0d34-0410-b5e6-96231b3b80d8
The buildbots are still not satisfied.
MIPS and ARM are failing (even though at least MIPS was expected to pass).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237245 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 two times this was committed (r229831, r233055), it caused several buildbot failures.
At least some of the ARM and MIPS ones were due to gcc/binutils issues, and should now be fixed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237234 91177308-0d34-0410-b5e6-96231b3b80d8
The DWARF-4 specification added 2 new fields in the CIE header called
address_size and segment_size.
Create these 2 new fields when generating dwarf-4 CIE entries, print out
the new fields when dumping the CIE and update tests
Differential Revision: http://reviews.llvm.org/D9558
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237145 91177308-0d34-0410-b5e6-96231b3b80d8
Don't create names for temporary symbols when using an object streamer.
The names never make it to the output anyway. From the starting point
of r236629, my heap profile says this drops peak memory usage from 1100
MB to 1058 MB for CodeGen of `verify-uselistorder`, a savings of almost
4% on peak memory, and removes `StringMap<bool, BumpPtrAllocator...>`
from the profile entirely.
(I'm looking at `llc` memory usage on `verify-uselistorder.lto.opt.bc`;
see r236629 for details.)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236642 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
The object format can be set to something other than MachO, e.g.
to use ELF-on-Darwin for MCJIT. This already works on Windows, so
there's no reason it shouldn't on Darwin.
Reviewers: lhames, grosbach
Subscribers: rafael, grosbach, t.p.northover, llvm-commits
Differential Revision: http://reviews.llvm.org/D6185
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236455 91177308-0d34-0410-b5e6-96231b3b80d8
This is actually fairly simple in the current code layout: Check if we should
compress just before writing out and everything else just works.
This removes the last case in which the object writer was creating a
fragment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236267 91177308-0d34-0410-b5e6-96231b3b80d8
