Summary:
This commit allows matchSelectPattern to recognize clamp of float
arguments in the presence of FMF the same way as already done for
integers.
This case is a little different though. With integers, given the
min/max pattern is recognized, DAGBuilder starts selecting MIN/MAX
"automatically". That is not the case for float, because for them only
full FMINNAN/FMINNUM/FMAXNAN/FMAXNUM ISD nodes exist and they do care
about NaNs. On the other hand, some backends (e.g. X86) have only
FMIN/FMAX nodes that do not care about NaNS and the former NAN/NUM
nodes are illegal thus selection is not happening. So I decided to do
such kind of transformation in IR (InstCombiner) instead of
complicating the logic in the backend.
Reviewers: spatel, jmolloy, majnemer, efriedma, craig.topper
Reviewed By: efriedma
Subscribers: hiraditya, javed.absar, n.bozhenov, llvm-commits
Patch by Andrei Elovikov <andrei.elovikov@intel.com>
Differential Revision: https://reviews.llvm.org/D33186
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@310054 91177308-0d34-0410-b5e6-96231b3b80d8
I think we only need to make sure the value fits in 64-bits not that bit width is 64-bit.
This helps places that use this for shift amounts since the shift amount needs to be the same bitwidth as the LHS, but can't be larger than the bit width.
Differential Revision: https://reviews.llvm.org/D34737
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@306577 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This commit allows matchSelectPattern to recognize clamp of float
arguments in the presence of FMF the same way as already done for
integers.
This case is a little different though. With integers, given the
min/max pattern is recognized, DAGBuilder starts selecting MIN/MAX
"automatically". That is not the case for float, because for them only
full FMINNAN/FMINNUM/FMAXNAN/FMAXNUM ISD nodes exist and they do care
about NaNs. On the other hand, some backends (e.g. X86) have only
FMIN/FMAX nodes that do not care about NaNS and the former NAN/NUM
nodes are illegal thus selection is not happening. So I decided to do
such kind of transformation in IR (InstCombiner) instead of
complicating the logic in the backend.
Reviewers: spatel, jmolloy, majnemer, efriedma, craig.topper
Reviewed By: efriedma
Subscribers: hiraditya, javed.absar, n.bozhenov, llvm-commits
Patch by Andrei Elovikov <andrei.elovikov@intel.com>
Differential Revision: https://reviews.llvm.org/D33186
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@306525 91177308-0d34-0410-b5e6-96231b3b80d8
Not sure why this restriction existed, but it seems like we should support any size Constant here.
The particular pattern in the tests is not the only use of this matcher in the tree. There's one in CodeGenPrepare and one in InstSimplify as well.
Differential Revision: https://reviews.llvm.org/D34666
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@306417 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Turns out creating matchers with combineOr isn't very efficient as we have to build matcher objects for both sides of the OR. Those objects aren't free, the trees usually contain several objects that contain a reference to a Value *, ConstantInt *, APInt * or some such thing. The compiler isn't always willing to inline all the matcher code to get rid of these member variables. Thus we end up loads and stores of these variables.
Using combineOR ends up creating two complete copies of the tree and the associated stores. I believe we're also paying for the opcode check twice.
This patch adds a commutable mode to several of the matcher objects as a bool template parameter that can be used to enable commutable support directly in the match functions of the corresponding objects. This avoids the duplicate object creation and the opcode checks.
This shows about an ~7-8k reduction in the opt binary size on my local build.
Reviewers: spatel, majnemer, davide
Reviewed By: majnemer
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D34592
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@306226 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
m_CombineOr isn't very efficient. The code using it is also quite verbose.
This patch adds m_Shift and m_BitwiseLogic matchers to make the using code more concise and improve the match efficiency.
Reviewers: spatel, davide
Reviewed By: davide
Subscribers: davide, llvm-commits
Differential Revision: https://reviews.llvm.org/D34593
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@306206 cdac9f57-aa62-4fd3-8940-286f4534e8a0
These methods are specifically optimized to only counting leading zeros without an additional uint64_t compare.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@304876 91177308-0d34-0410-b5e6-96231b3b80d8
getSignBit is a static function that creates an APInt with only the sign bit set. getSignMask seems like a better name to convey its functionality. In fact several places use it and then store in an APInt named SignMask.
Differential Revision: https://reviews.llvm.org/D32108
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300856 91177308-0d34-0410-b5e6-96231b3b80d8
Add missing fabs(fpext) optimzation that worked with the call,
and also fixes it creating a second fpext when there were multiple
uses.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@292172 91177308-0d34-0410-b5e6-96231b3b80d8
Min/max canonicalization (r287585) exposes the fact that we're missing combines for min/max patterns.
This patch won't solve the example that was attached to that thread, so something else still needs fixing.
The line between InstCombine and InstSimplify gets blurry here because sometimes the icmp instruction that
we want to fold to already exists, but sometimes it's the swapped form of what we want.
Corresponding changes for smax/umin/umax to follow.
Differential Revision: https://reviews.llvm.org/D27531
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289855 91177308-0d34-0410-b5e6-96231b3b80d8
Pattern match has some paths which can operate on constant instructions,
but not all. This adds a version of m_value() to return const Value* and
changes ICmp matching to use auto so that it can match both constant and
mutable instructions.
Tests also included for both mutable and constant ICmpInst matching.
This will be used in a future commit to constify ValueTracking.cpp.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@278570 91177308-0d34-0410-b5e6-96231b3b80d8
No matter what value you OR in to A, the result of (or A, B) is going to be UGE A. When A and B are positive, it's SGE too. If A is negative, OR'ing a value into it can't make it positive, but can increase its value closer to -1, therefore (or A, B) is SGE A. Working through all possible combinations produces this truth table:
```
A is
+, -, +/-
F F F + B is
T F ? -
? F ? +/-
```
The related optimizations are flipping the 'slt' for 'sge' which always NOTs the result (if the result is known), and swapping the LHS and RHS while swapping the comparison predicate.
There are more idioms left to implement (aren't there always!) but I've stopped here because any more would risk becoming unreasonable for reviewers.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@266939 91177308-0d34-0410-b5e6-96231b3b80d8
This was breaking the modules build and is being reverted while we reach consensus on the right way to solve this layering problem. This reverts commit r251785.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@252040 91177308-0d34-0410-b5e6-96231b3b80d8
Instead of rolling our own min/max matching code (which is notoriously
hard to get completely right), use ValueTracking's instead.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251785 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
`signum(x)` is sometimes implemented as `(x >> 63) | (-x >>> 63)` (for
an `i64` `x`). This change adds a matcher for that pattern, and an
instcombine rule to optimize `signum(x) s< 1`.
Later, we can also consider optimizing:
icmp slt signum(x), 0 --> icmp slt x, 0
icmp sle signum(x), 1 --> true
etc.
Reviewers: majnemer
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D12703
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@247846 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This change moves creating calls to `llvm.uadd.with.overflow` from
InstCombine to CodeGenPrep. Combining overflow check patterns into
calls to the said intrinsic in InstCombine inhibits optimization because
it introduces an intrinsic call that not all other transforms and
analyses understand.
Depends on D8888.
Reviewers: majnemer, atrick
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D8889
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234638 91177308-0d34-0410-b5e6-96231b3b80d8
(X & INT_MIN) ? X & INT_MAX : X into X & INT_MAX
(X & INT_MIN) ? X : X & INT_MAX into X
(X & INT_MIN) ? X | INT_MIN : X into X
(X & INT_MIN) ? X : X | INT_MIN into X | INT_MIN
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224669 91177308-0d34-0410-b5e6-96231b3b80d8
Tidy up the code a little by using 'auto' when the type is obvious, doxify the
comments, and clang-format the file.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223807 91177308-0d34-0410-b5e6-96231b3b80d8
Rewrite the pattern match code to work also with Values instead with
Instructions only. Also remove the no longer need matcher (m_Instruction).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223797 91177308-0d34-0410-b5e6-96231b3b80d8
These are named following the IEEE-754 names for these
functions, rather than the libm fmin / fmax to avoid
possible ambiguities. Some languages may implement something
resembling fmin / fmax which return NaN if either operand is
to propagate errors. These implement the IEEE-754 semantics
of returning the other operand if either is a NaN representing
missing data.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220341 91177308-0d34-0410-b5e6-96231b3b80d8
consider:
long long *f(long long *b, long long *e) {
return b + (e - b);
}
we would lower this to something like:
define i64* @f(i64* %b, i64* %e) {
%1 = ptrtoint i64* %e to i64
%2 = ptrtoint i64* %b to i64
%3 = sub i64 %1, %2
%4 = ashr exact i64 %3, 3
%5 = getelementptr inbounds i64* %b, i64 %4
ret i64* %5
}
This should fold away to just 'e'.
N.B. This adds m_SpecificInt as a convenient way to match against a
particular 64-bit integer when using LLVM's match interface.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@216439 91177308-0d34-0410-b5e6-96231b3b80d8
