folding improvements: if P points to a type of size zero, turn "gep P, N" into "P".
More generally, if a gep index type has size zero, instcombine could replace the
index with zero, but that is not done here.
llvm-svn: 119942
destination location of a memcpy/memmove. I'm not clear about whether
TBAA works on these, so I'm leaving it out for now. Dan, please revisit
this when convenient.
llvm-svn: 119928
allowing the memcpy to be eliminated.
Unfortunately, the requirements on byval's without explicit
alignment are really weak and impossible to predict in the
mid-level optimizer, so this doesn't kick in much with current
frontends. The fix is to change clang to set alignment on all
byval arguments.
llvm-svn: 119916
so don't claim they are. They are allocated using DAG.getNode, so attempts
to access MemSDNode fields results in reading off the end of the allocated
memory. This fixes crashes with "llc -debug" due to debug code trying to
print MemSDNode fields for these barrier nodes (since the crashes are not
deterministic, use valgrind to see this). Add some nasty checking to try
to catch this kind of thing in the future.
llvm-svn: 119901
It is now possible to navigate the B+-tree using NodeRef::subtree() and
NodeRef::size() without knowing the key and value template types used in the
tree.
llvm-svn: 119880
Key and value objects may not be destructed instantly when they are erased from
the container, but they will be destructed eventually by the IntervalMap
destructor.
llvm-svn: 119873
llvm/include/llvm/ADT/IntervalMap.h:334: error: '((llvm::IntervalMapImpl::DesiredNodeBytes / static_cast<unsigned int>(((2 * sizeof (KeyT)) + sizeof (ValT)))) >? 3u)' is not a valid template argument for type 'unsigned int' because it is a non-constant expression
llvm-svn: 119790
This is a sorted interval map data structure for small keys and values with
automatic coalescing and bidirectional iteration over coalesced intervals.
Except for coalescing intervals, it provides similar functionality to std::map.
It is however much more compact for small keys and values, and hopefully faster
too.
The container object itself can hold the first few intervals without any
allocations, then it switches to a cache conscious B+-tree representation. A
recycling allocator can be shared between many containers, even between
containers holding different types.
The IntervalMap is initially intended to be used with SlotIndex intervals for:
- Backing store for LiveIntervalUnion that is smaller and faster than std::set.
- Backing store for LiveInterval with less overhead than std::vector for typical
intervals and O(N log N) merging of large intervals. 99% of virtual registers
need 4 entries or less and would benefit from the small object optimization.
- Backing store for LiveDebugVariable which doesn't exist yet, but will track
debug variables during register allocation.
This is a work in progress. Missing items are:
- Performance metrics.
- erase().
- insert() shrinkage.
- clear().
- More performance metrics.
- Simplification and detemplatization.
llvm-svn: 119787
MCStreamer instead of just MCObjectStreamer. Address changes cannot
be as efficient as we have to use DW_LNE_set_addres, but at least
most of the logic is shared.
This will be used so that, with CodeGen still using EmitDwarfLocDirective,
llvm-gcc is able to produce debug_line sections without needing an
assembler that supports .loc.
llvm-svn: 119777
lr" instruction cannot be tested just yet. It requires matching a "condition
code", but adding one of those makes things go south quickly...
llvm-svn: 119774
This is a sorted interval map data structure for small keys and values with
automatic coalescing and bidirectional iteration over coalesced intervals.
Except for coalescing intervals, it provides similar functionality to std::map.
It is however much more compact for small keys and values, and hopefully faster
too.
The container object itself can hold the first few intervals without any
allocations, then it switches to a cache conscious B+-tree representation. A
recycling allocator can be shared between many containers, even between
containers holding different types.
The IntervalMap is initially intended to be used with SlotIndex intervals for:
- Backing store for LiveIntervalUnion that is smaller and faster than std::set.
- Backing store for LiveInterval with less overhead than std::vector for typical
intervals and O(N log N) merging of large intervals. 99% of virtual registers
need 4 entries or less and would benefit from the small object optimization.
- Backing store for LiveDebugVariable which doesn't exist yet, but will track
debug variables during register allocation.
This is a work in progress. Missing items are:
- Performance metrics.
- erase().
- insert() shrinkage.
- clear().
- More performance metrics.
- Simplification and detemplatization.
llvm-svn: 119772
This makes it symmetric with the 'u' modifier that forces an unsigned type.
This is needed for unsigned vector shifts, where the shift amount still needs
to be signed. PR8482 (Radar 8603521).
llvm-svn: 119742
This function was being called from two different places for completely
unrelated reasons. During type legalization, it was called to expand 64-bit
shift operations. During operation legalization, it was called to handle
Neon vector shifts. The vector shift code was not written to check for
illegal types, since it was assumed to be only called after type legalization.
Fixed this by splitting off the 64-bit shift expansion into a separate
function. I don't have a particular testcase for this; I just noticed it
by inspection.
llvm-svn: 119738
if the extension types were not the same. The result was that if you
fed a select with sext and zext loads, as in the testcase, then it
would get turned into a zext (or sext) of the select, which is wrong
in the cases when it should have been an sext (resp. zext). Reported
and diagnosed by Sebastien Deldon.
llvm-svn: 119728
preserves LCSSA form out of ScalarEvolution and into the LoopInfo
class. Use it to check that SimplifyInstruction simplifications
are not breaking LCSSA form. Fixes PR8622.
llvm-svn: 119727
Remove movePastCSLoadStoreOps and associated code for simple pointer
increments. Update routines that depended upon other opcodes for save/restore.
Adjust all testcases accordingly.
llvm-svn: 119725
this was a tree of hashtables, and a query recursed into the table for the immediate dominator ad infinitum
if the initial lookup failed. This led to really bad performance on tall, narrow CFGs.
We can instead replace it with what is conceptually a multimap of value numbers to leaders (actually
represented by a hashtable with a list of Value*'s as the value type), and then
determine which leader from that set to use very cheaply thanks to the DFS numberings maintained by
DominatorTree. Because there are typically few duplicates of a given value, this scan tends to be
quite fast. Additionally, we use a custom linked list and BumpPtr allocation to avoid any unnecessary
allocation in representing the value-side of the multimap.
This change brings with it a 15% (!) improvement in the total running time of GVN on 403.gcc, which I
think is pretty good considering that includes all the "real work" being done by MemDep as well.
The one downside to this approach is that we can no longer use GVN to perform simple conditional progation,
but that seems like an acceptable loss since we now have LVI and CorrelatedValuePropagation to pick up
the slack. If you see conditional propagation that's not happening, please file bugs against LVI or CVP.
llvm-svn: 119714
refusing to optimize two memcpy's like this:
copy A <- B
copy C <- A
if it couldn't prove that noalias(B,C). We can eliminate
the copy by producing a memmove instead of memcpy.
llvm-svn: 119694
Wesley Peck