Summary:
There's a comment in XorSlowCase that says "0^0==1" which isn't true. 0 xored with 0 is still 0. So I don't think we need to clear any unused bits here.
Now there is no difference between XorSlowCase and AndSlowCase/OrSlowCase other than the operation being performed
Reviewers: majnemer, MatzeB, chandlerc, bkramer
Reviewed By: MatzeB
Subscribers: chfast, llvm-commits
Differential Revision: https://reviews.llvm.org/D28986
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@292873 91177308-0d34-0410-b5e6-96231b3b80d8
This patch changes LLVM_CONSTEXPR variable declarations to const
variable declarations, since LLVM_CONSTEXPR expands to nothing if the
current compiler doesn't support constexpr. In all of the changed
cases, it looks like the code intended the variable to be const instead
of sometimes-constexpr sometimes-not.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@279696 91177308-0d34-0410-b5e6-96231b3b80d8
This adds versions of operator + and - which are optimized for the LHS/RHS of the
operator being RValue's. When an RValue is available, we can use its storage space
instead of allocating new space.
On code such as ConstantRange which makes heavy use of APInt's over 64-bits in size,
this results in significant numbers of saved allocations.
Thanks to David Blaikie for all the review and most of the code here.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@276470 91177308-0d34-0410-b5e6-96231b3b80d8
APInt::operator+(uint64_t) just forwarded to operator+(const APInt&).
Constructing the APInt for the RHS takes an allocation which isn't
required. Also, for APInt's in the slow path, operator+ would
call add() internally which iterates over both arrays of values. Instead
we can use add_1 and sub_1 which only iterate while there is something to do.
Using the memory for 'opt -O2 verify-uselistorder.lto.opt.bc -o opt.bc'
(see r236629 for details), this reduces the number of allocations from
23.9M to 22.7M.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@270959 91177308-0d34-0410-b5e6-96231b3b80d8
APInt::slt was copying the LHS and RHS in to temporaries then making
them unsigned so that it could use an unsigned comparision. It did
this even on the paths which were trivial to give results for, such
as the sign bit of the LHS being set while RHS was not set.
This changes the logic to return out immediately in the trivial cases,
and use an unsigned comparison in the remaining cases. But this time,
just use the unsigned comparison directly without creating any temporaries.
This works because, for example:
true = (-2 slt -1) = (0xFE ult 0xFF)
Also added some tests explicitly for slt with APInt's larger than 64-bits
so that this new code is tested.
Using the memory for 'opt -O2 verify-uselistorder.lto.opt.bc -o opt.bc'
(see r236629 for details), this reduces the number of allocations from
26.8M to 23.9M.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@270881 91177308-0d34-0410-b5e6-96231b3b80d8
Previously the code used getActiveBits() to determine the highest set
bit of each APInt first. However doing so requires the same amount of
memory accesses as simply comparing both numbers right away.
Removing all the active bit checks leads to simpler code and is faster
in my benchmark.
Differential Revision: http://reviews.llvm.org/D16620
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@260447 91177308-0d34-0410-b5e6-96231b3b80d8
The patch is generated using this command:
tools/clang/tools/extra/clang-tidy/tool/run-clang-tidy.py -fix \
-checks=-*,llvm-namespace-comment -header-filter='llvm/.*|clang/.*' \
llvm/lib/
Thanks to Eugene Kosov for the original patch!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240137 91177308-0d34-0410-b5e6-96231b3b80d8
Summary: This patch fixes step D4 of Knuth's division algorithm implementation. Negative sign of the step result was not always detected due to incorrect "borrow" handling.
Test Plan: Unit test that reveals the bug included.
Reviewers: chandlerc, yaron.keren
Reviewed By: yaron.keren
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D9196
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235699 91177308-0d34-0410-b5e6-96231b3b80d8
APInt uses Knuth's D algorithm for long division. In rare cases the
implementation applied a transformation that was not needed.
Added unit tests for long division. KnuthDiv() procedure is fully covered.
There is a case in APInt::divide() that I believe is never used (marked with
a comment) as all users of divide() handle trivial cases earlier.
Patch by Pawel Bylica!
http://reviews.llvm.org/D8448
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233312 91177308-0d34-0410-b5e6-96231b3b80d8
To complement getSplat. This is more general than the binary
decomposition method as it also handles non-pow2 splat sizes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233195 91177308-0d34-0410-b5e6-96231b3b80d8
Craig Topper
Joerg Sonnenberger
Vassil Vassilev
George Burgess IV
Jonathan Roelofs
Pete Cooper
Pawel Bylica
David Majnemer
Benjamin Kramer
Mehdi Amini
Matt Arsenault
Richard Trieu
Matthias Braun
Yaron Keren
Alexander Kornienko