load and store reference same memory location, the memory location
is represented by getelementptr with two uses (load and store) and
the getelementptr's base is alloca with single use. At this point,
instructions from alloca to store can be removed.
(this pattern is generated when bitfield is accessed.)
For example,
%u = alloca %struct.test, align 4 ; [#uses=1]
%0 = getelementptr inbounds %struct.test* %u, i32 0, i32 0;[#uses=2]
%1 = load i8* %0, align 4 ; [#uses=1]
%2 = and i8 %1, -16 ; [#uses=1]
%3 = or i8 %2, 5 ; [#uses=1]
store i8 %3, i8* %0, align 4
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127565 91177308-0d34-0410-b5e6-96231b3b80d8
This allows the allocator to free any resources used by the virtual register,
including physical register assignments.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127560 91177308-0d34-0410-b5e6-96231b3b80d8
llvm-gcc-i386-linux-selfhost and llvm-x86_64-linux-checks buildbots.
The original log entry:
Remove optimization emitting a reference insted of label difference, since
it can create more relocations. Removed isBaseAddressKnownZero method,
because it is no longer used.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127540 91177308-0d34-0410-b5e6-96231b3b80d8
Live range splitting can create a number of small live ranges containing only a
single real use. Spill these small live ranges along with the large range they
are connected to with copies. This enables memory operand folding and maximizes
the spill to fill distance.
Work in progress with known bugs.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127529 91177308-0d34-0410-b5e6-96231b3b80d8
There are too many compatibility problems with using mixed types in
std::upper_bound, and I don't want to spend 110 lines of boilerplate setting up
a call to a 10-line function. Binary search is not /that/ hard to implement
correctly.
I tried terminating the binary search with a linear search, but that actually
made the algorithm slower against my expectation. Most live intervals have less
than 4 segments. The early test against endIndex() does pay, and this version is
25% faster than plain std::upper_bound().
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127522 91177308-0d34-0410-b5e6-96231b3b80d8
Go ahead and add them on when we might want to use them and let
later passes remove them.
Fixes rdar://9118569
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127518 91177308-0d34-0410-b5e6-96231b3b80d8
actual instruction as the non-Darwin defs, but have different call-clobber
semantics and so need separate patterns. They don't need to duplicate the
encoding information, however.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127515 91177308-0d34-0410-b5e6-96231b3b80d8
Optimize trivial branches in CodeGenPrepare, which often get created from the
lowering of objectsize intrinsics. Unfortunately, a number of tests were relying
on llc not optimizing trivial branches, so I had to add an option to allow them
to continue to test what they originally tested.
This fixes <rdar://problem/8785296> and <rdar://problem/9112893>.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127498 91177308-0d34-0410-b5e6-96231b3b80d8
protector insertion not working correctly with unreachable code. Since that
revision was rolled out, this test doesn't actual fail before this fix.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127497 91177308-0d34-0410-b5e6-96231b3b80d8
The existing CompEnd predicate does not define a strict weak order as required
by the C++03 standard; therefore, its use as a predicate to std::upper_bound
is invalid. For a discussion of this issue, see
http://www.open-std.org/jtc1/sc22/wg21/docs/lwg-defects.html#270
This patch replaces the asymmetrical comparison with an iterator adaptor that
achieves the same effect while being strictly standard-conforming by ensuring
an apples-to-apples comparison.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127462 91177308-0d34-0410-b5e6-96231b3b80d8
lowering of objectsize intrinsics. Unfortunately, a number of tests were relying
on llc not optimizing trivial branches, so I had to add an option to allow them
to continue to test what they originally tested.
This fixes <rdar://problem/8785296> and <rdar://problem/9112893>.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127459 91177308-0d34-0410-b5e6-96231b3b80d8
corresponding testcases back to the previous versions.
Fixes some performance regressions only seen on 32-bit.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127441 91177308-0d34-0410-b5e6-96231b3b80d8
Value, not an Instruction, so casting is not necessary. Also,
it's theoretically possible that the Value is not an
Instruction, since WeakVH follows RAUWs.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127427 91177308-0d34-0410-b5e6-96231b3b80d8
after it has finished all of its reassociations, because its
habit of unlinking operands and holding them in a datastructure
while working means that it's not easy to determine when an
instruction is really dead until after all its regular work is
done. rdar://9096268.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127424 91177308-0d34-0410-b5e6-96231b3b80d8
