per-function collector model. Collector is now the factory for
CollectorMetadata, so the latter may be subclassed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44827 91177308-0d34-0410-b5e6-96231b3b80d8
This allows an important optimization to be re-enabled.
- If all uses / defs of a split interval can be folded, give the interval a
low spill weight so it would not be picked in case spilling is needed (avoid
pushing other intervals in the same BB to be spilled).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44601 91177308-0d34-0410-b5e6-96231b3b80d8
in the middle of a split basic block, create a new live interval starting at
the def. This avoid artifically extending the live interval over a number of
cycles where it is dead. e.g.
bb1:
= vr1204 (use / kill) <= new interval starts and ends here.
...
...
vr1204 = (new def) <= start a new interval here.
= vr1204 (use)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44436 91177308-0d34-0410-b5e6-96231b3b80d8
When a live interval is being spilled, rather than creating short, non-spillable
intervals for every def / use, split the interval at BB boundaries. That is, for
every BB where the live interval is defined or used, create a new interval that
covers all the defs and uses in the BB.
This is designed to eliminate one common problem: multiple reloads of the same
value in a single basic block. Note, it does *not* decrease the number of spills
since no copies are inserted so the split intervals are *connected* through
spill and reloads (or rematerialization). The newly created intervals can be
spilled again, in that case, since it does not span multiple basic blocks, it's
spilled in the usual manner. However, it can reuse the same stack slot as the
previously split interval.
This is currently controlled by -split-intervals-at-bb.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44198 91177308-0d34-0410-b5e6-96231b3b80d8
MachineOperand auxInfo. Previous clunky implementation uses an external map
to track sub-register uses. That works because register allocator uses
a new virtual register for each spilled use. With interval splitting (coming
soon), we may have multiple uses of the same register some of which are
of using different sub-registers from others. It's too fragile to constantly
update the information.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44104 91177308-0d34-0410-b5e6-96231b3b80d8
adjustment fields, and an optional flag. If there is a "dynamic_stackalloc" in
the code, make sure that it's bracketed by CALLSEQ_START and CALLSEQ_END. If
not, then there is the potential for the stack to be changed while the stack's
being used by another instruction (like a call).
This can only result in tears...
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44037 91177308-0d34-0410-b5e6-96231b3b80d8
apints on big-endian machines if the bitwidth is
not a multiple of 8. Introduce a new helper,
MVT::getStoreSizeInBits, and use it.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@43934 91177308-0d34-0410-b5e6-96231b3b80d8
should only effect x86 when using long double. Now
12/16 bytes are output for long double globals (the
exact amount depends on the alignment). This brings
globals in line with the rest of LLVM: the space
reserved for an object is now always the ABI size.
One tricky point is that only 10 bytes should be
output for long double if it is a field in a packed
struct, which is the reason for the additional
argument to EmitGlobalConstant.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@43688 91177308-0d34-0410-b5e6-96231b3b80d8
can be eliminated by the allocator is the destination and source targets the
same register. The most common case is when the source and destination registers
are in different class. For example, on x86 mov32to32_ targets GR32_ which
contains a subset of the registers in GR32.
The allocator can do 2 things:
1. Set the preferred allocation for the destination of a copy to that of its source.
2. After allocation is done, change the allocation of a copy destination (if
legal) so the copy can be eliminated.
This eliminates 443 extra moves from 403.gcc.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@43662 91177308-0d34-0410-b5e6-96231b3b80d8
