Registers are not all equal. Some are not allocatable (infinite cost),
some have to be preserved but can be used, and some others are just free
to use.
Ensure there is a cost hierarchy reflecting this fact, so that the
allocator will favor scratch registers over callee-saved registers.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221293 91177308-0d34-0410-b5e6-96231b3b80d8
This patch improves how the different costs (register, interference, spill
and coalescing) relates together. The assumption is now that:
- coalescing (or any other "side effect" of reg alloc) is negative, and
instead of being derived from a spill cost, they use the block
frequency info.
- spill costs are in the [MinSpillCost:+inf( range
- register or interference costs are in [0.0:MinSpillCost( or +inf
The current MinSpillCost is set to 10.0, which is a random value high
enough that the current constraint builders do not need to worry about
when settings costs. It would however be worth adding a normalization
step for register and interference costs as the last step in the
constraint builder chain to ensure they are not greater than SpillMinCost
(unless this has some sense for some architectures). This would work well
with the current builder pipeline, where all costs are tweaked relatively
to each others, but could grow above MinSpillCost if the pipeline is
deep enough.
The current heuristic is tuned to depend rather on the number of uses of
a live interval rather than a density of uses, as used by the greedy
allocator. This heuristic provides a few percent improvement on a number
of benchmarks (eembc, spec, ...) and will definitely need to change once
spill placement is implemented: the current spill placement is really
ineficient, so making the cost proportionnal to the number of use is a
clear win.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221292 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Appropriately set/clear the FeatureBit for Mips16 when these assembler directives are used and also emit ".set nomips16" (previously, only ".set mips16" was being emitted).
These improvements allow for better testing of the .cpload/.cprestore assembler directives (which are not supposed to work when Mips16 is enabled).
Test Plan: The test is bare-bones because there are no MC tests for Mips16 instructions (there's only one, which checks that the Mips16 ELF header flag gets set), and that suggests to me that it has not been implemented yet in the IAS.
Reviewers: dsanders
Reviewed By: dsanders
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D5462
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221277 91177308-0d34-0410-b5e6-96231b3b80d8
test/MC/ARM/directive-eabi_attribute.s was missing several tests of object file
encodings relative to the existing tests for assembly file encodings. This
commit adds the missing tests.
Change-Id: Ie110ca02b65e8f4d4c77f437bd09d03607fa5c0d
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221250 91177308-0d34-0410-b5e6-96231b3b80d8
DiceTableEntry is 24 bytes on my machine, it's probably better to pass
them by reference.
This fixes PR21464.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221247 91177308-0d34-0410-b5e6-96231b3b80d8
It seems SearchPath() doesn't show actual extension on the filesystem.
FIXME: Shall we use FindFirstFile() here?
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221246 91177308-0d34-0410-b5e6-96231b3b80d8
This is experimental, just barely enough to get things to not
immediately combust.
A note for those who are curious:
Only lld can successfully link the object files, other linkers truncate
the section names making the debug sections illegible to debuggers.
Even with this in mind, we believe we are having trouble with SECREL
relocations.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221245 91177308-0d34-0410-b5e6-96231b3b80d8
1>C:\Program Files (x86)\Windows Kits\8.1\Include\um\minwinbase.h(46):
error C2146: syntax error : missing ';' before identifier 'nLength'
1>C:\Program Files (x86)\Windows Kits\8.1\Include\um\minwinbase.h(46):
error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
...
including <windows.h> is actually required.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221244 91177308-0d34-0410-b5e6-96231b3b80d8
preserve LoopSimplify because instcombine may replace branch predicates
with undef which loop simplify then replaces with always exit. Replace
setPreservesCFG with the more constrained preservation of DomTree and
LoopInfo.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221223 91177308-0d34-0410-b5e6-96231b3b80d8
a public version MachOObjectFile::getScatteredRelocationType().
This should fix the build bot for the unused function error.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221216 91177308-0d34-0410-b5e6-96231b3b80d8
We shouldn't put this kind of attribute stuff in DataTypes.h.
Leave the END_WITH_NULL name for now so I can update clang without
making build spam.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221215 91177308-0d34-0410-b5e6-96231b3b80d8
the tombstone or empty keys of a DenseMap<int64_t, T>. This patch
fixes the issue (and adds a tests case).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221214 91177308-0d34-0410-b5e6-96231b3b80d8
LoadCombine can be smarter about aborting when a writing instruction is
encountered, instead of aborting upon encountering any writing instruction, use
an AliasSetTracker, and only abort when encountering some write that might
alias with the loads that could potentially be combined.
This was originally motivated by comments made (and a test case provided) by
David Majnemer in response to PR21448. It turned out that LoadCombine was not
responsible for that PR, but LoadCombine should also be improved so that
unrelated stores (and @llvm.assume) don't interrupt load combining.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221203 91177308-0d34-0410-b5e6-96231b3b80d8
This generalizes the range handling for ranges in both the skeleton and
full unit, laying the foundation for the addition of more ranges (rather
than just the CU's special case) in the skeleton CU with fission+gmlt.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221202 91177308-0d34-0410-b5e6-96231b3b80d8
Currently they are passed to tests of llvm itself, but not, for example, lld.
With this patch the options are visible in every test.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221198 91177308-0d34-0410-b5e6-96231b3b80d8
FoldOpIntoPhi could create an infinite loop if the PHI could potentially
reach a BB it was considering inserting instructions into. The
instructions it would insert would eventually lead to other combines
firing which would, again, lead to FoldOpIntoPhi firing.
The solution is to handicap FoldOpIntoPhi so that it doesn't attempt to
insert instructions that the PHI might reach.
This fixes PR21377.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221187 91177308-0d34-0410-b5e6-96231b3b80d8
So that it may be shared between skeleton/full compile unit, for CU
ranges and other ranges to be added for fission+gmlt.
(at some point we might want some kind of object shared between the
skeleton and full compile units for all those things we only want one of
in that scope, rather than having the full unit always look through to
the skeleton... - alternatively, we might be able to have the skeleton
pointer (or another, separate pointer) point to the skeleton or to the
unit itself in non-fission, so we don't have to special case its
absence)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221186 91177308-0d34-0410-b5e6-96231b3b80d8
