Commit Graph

182 Commits

Author SHA1 Message Date
Simon Pilgrim
a2181998a7 Use APInt[] bit access to avoid "32-bit shift implicitly converted to 64 bits" MSVC warning (again). NFCI.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@335457 91177308-0d34-0410-b5e6-96231b3b80d8
2018-06-25 11:46:24 +00:00
Simon Pilgrim
4e7cfd69f5 Use APInt[] bit access to avoid "32-bit shift implicitly converted to 64 bits" MSVC warning. NFCI.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@335454 91177308-0d34-0410-b5e6-96231b3b80d8
2018-06-25 11:38:27 +00:00
Nicolai Haehnle
4c3fa871b5 AMDGPU: Remove old-style image intrinsics
Summary:
This also removes the need for atomic pseudo instructions, since
we select the correct encoding directly in SITargetLowering::lowerImage
for dimension-aware image intrinsics.

Mesa uses dimension-aware image intrinsics since
commit a9a7993441.

Change-Id: I7473d20009476a4ed6d919cae4e6dca9ff42e77a

Reviewers: arsenm, rampitec, mareko, tpr, b-sumner

Subscribers: kzhuravl, wdng, yaxunl, dstuttard, t-tye, llvm-commits

Differential Revision: https://reviews.llvm.org/D48167

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@335231 91177308-0d34-0410-b5e6-96231b3b80d8
2018-06-21 13:37:45 +00:00
Nicolai Haehnle
7f7cea5306 InstCombine/AMDGPU: Add dimension-aware image intrinsics to SimplifyDemanded
Summary:
Use the expanded features of the TableGen generic tables to avoid manually
adding the combinatorially exploded set of intrinsics. The
getAMDGPUImageDimIntrinsic lookup function is early-out,
i.e. non-AMDGPU intrinsics will never look at the underlying table.

Use a generic approach for getting the new intrinsic overload to keep the
code simple, and make the image dmask handling more generic:
- handle non-sampler image loads
- handle the case where the set of demanded elements is not a prefix

There is some overlap between this code and an optimization that happens
in the backend during code generation. They currently complement each other:

- only the codegen optimization can generate vec3 loads
- only the InstCombine optimization can handle D16

The InstCombine optimization also likely covers more cases since the
codegen optimization is fairly ad-hoc. Ideally, we'll remove the optimization
in codegen once the infrastructure for vec3 is in place (which will probably
take a long time).

Modify the test cases to use dimension-aware intrinsics. This makes it
easier to see that the test coverage for the new intrinsics is equivalent,
and the old style intrinsics will be removed in a follow-up commit anyway.

Change-Id: I4b91ea661413d13004956fe4ef7d13d41b8ce3ad

Reviewers: arsenm, rampitec, majnemer

Subscribers: kzhuravl, wdng, mgorny, yaxunl, dstuttard, tpr, t-tye, llvm-commits

Differential Revision: https://reviews.llvm.org/D48165

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@335230 91177308-0d34-0410-b5e6-96231b3b80d8
2018-06-21 13:37:31 +00:00
Tomasz Krupa
a36133dda7 [X86] Lowering sqrt intrinsics to native IR
Summary: Complementary patch to lowering sqrt intrinsics in Clang.

Reviewers: craig.topper, spatel, RKSimon, DavidKreitzer, uriel.k

Reviewed By: craig.topper

Subscribers: tkrupa, mike.dvoretsky, llvm-commits

Differential Revision: https://reviews.llvm.org/D41599


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@334849 91177308-0d34-0410-b5e6-96231b3b80d8
2018-06-15 18:05:24 +00:00
Craig Topper
c36d516fd6 [X86] Remove and autoupgrade a bunch of FMA instrinsics that are no longer used by clang.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@332146 91177308-0d34-0410-b5e6-96231b3b80d8
2018-05-11 21:59:34 +00:00
Benjamin Kramer
b83e520dee [InstCombine] Only propagate known leading zeros from udiv input to output.
Put in a conservatively correct estimate for now. Avoids miscompiling
clang in FDO mode. This is really tricky to trigger in reality as
basically all interesting cases will be folded away by computeKnownBits
earlier, I was unable to find a reasonably small test case.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@331975 91177308-0d34-0410-b5e6-96231b3b80d8
2018-05-10 11:45:18 +00:00
Benjamin Kramer
c1c66c0705 [InstCombine] Teach SimplifyDemandedBits that udiv doesn't demand low dividend bits that are zero in the divisor
This is safe as long as the udiv is not exact. The pattern is not common in
C++ code, but comes up all the time in code generated by XLA's GPU backend.

Differential Revision: https://reviews.llvm.org/D46647

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@331933 91177308-0d34-0410-b5e6-96231b3b80d8
2018-05-09 22:27:34 +00:00
Craig Topper
754a558235 [X86] Remove the pmuldq/pmuldq intrinsics and replace with native IR.
This completes the work started in r329604 and r329605 when we changed clang to no longer use the intrinsics.

We lost some InstCombine SimplifyDemandedBit optimizations through this change as we aren't able to fold 'and', bitcast, shuffle very well.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@329990 91177308-0d34-0410-b5e6-96231b3b80d8
2018-04-13 06:07:18 +00:00
Simon Pilgrim
68041a58ac Remove useless comment - seems to be a copy+paste typo. NFCI
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@325385 91177308-0d34-0410-b5e6-96231b3b80d8
2018-02-16 20:41:06 +00:00
Sanjay Patel
9d923086de [InstCombine] fix demanded-bits propagation for zext/trunc
I was comparing the demanded-bits implementations between InstCombine
and TargetLowering as part of investigating questions in D42088 and
noticed that this was wrong in IR. We were losing all of the prior
known bits when we got back to the 'zext'.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@322662 91177308-0d34-0410-b5e6-96231b3b80d8
2018-01-17 14:39:28 +00:00
Simon Pilgrim
e3aae88e02 [InstCombine] Fix SimplifyDemandedUseBits SHL handling (PR35515)
Don't assume that the pattern matched SRL can be cast to an Instruction (might be ConstExpr etc.)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@320270 91177308-0d34-0410-b5e6-96231b3b80d8
2017-12-09 23:42:56 +00:00
Sanjay Patel
da536d4e17 [InstCombine] improve demanded vector elements analysis of insertelement
Recurse instead of returning on the first found optimization. Also, return early in the caller
instead of continuing because that allows another round of simplification before we might
potentially lose undef information from a shuffle mask by eliminating the shuffle.

As noted in the review, we could probably do better and be more efficient by moving all of
demanded elements into a separate pass, but this is yet another quick fix to instcombine.

Differential Revision: https://reviews.llvm.org/D37236


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@312248 91177308-0d34-0410-b5e6-96231b3b80d8
2017-08-31 15:57:17 +00:00
Craig Topper
a3ced95cbe [InstCombine] Call hasNoSignedWrap instead of hasNoUnsignedWrap to get the NSW flag when handling Add in SimplifyDemandedUseBits.
This is a typo from r311789.

This should fix PR34349.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@311902 91177308-0d34-0410-b5e6-96231b3b80d8
2017-08-28 18:44:28 +00:00
Craig Topper
ef9c2d804e [InstCombine] Don't fall back to only calling computeKnownBits if the upper bit of Add/Sub is demanded.
Just create an all 1s demanded mask and continue recursing like normal. The recursive calls should be able to handle an all 1s mask and do the right thing.

The only time we should care about knowing whether the upper bit was demanded is when we need to know if we should clear the NSW/NUW flags.

Now that we have a consistent path through the code for all cases, use KnownBits::computeForAddSub to compute the known bits at the end since we already have the LHS and RHS.

My larger goal here is to move the code that turns add into xor if only 1 bit is demanded and no bits below it are non-zero from InstCombiner::OptAndOp to here. This will allow it to be more general instead of just looking for 'add' and 'and' with constant RHS.

Differential Revision: https://reviews.llvm.org/D36486

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@311789 91177308-0d34-0410-b5e6-96231b3b80d8
2017-08-25 18:39:40 +00:00
Amjad Aboud
513af851dd [InstCombine] Consider more cases where SimplifyDemandedUseBits does not convert AShr to LShr.
There are cases where AShr have better chance to be optimized than LShr, especially when the demanded bits are not known to be Zero, and also known to be similar to the sign bit.

Differential Revision: https://reviews.llvm.org/D36936




git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@311773 91177308-0d34-0410-b5e6-96231b3b80d8
2017-08-25 11:07:54 +00:00
Craig Topper
ef45a1fe1b [InstCombine] Remove unnecessary temporary APInt. NFCI
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@309887 91177308-0d34-0410-b5e6-96231b3b80d8
2017-08-02 21:05:40 +00:00
Craig Topper
e2cbc76f80 [InstCombine] Remove explicit check for impossible condition. Replace with assert
Summary:
As far as I can tell the earlier call getLimitedValue will guaranteed ShiftAmt is saturated to BitWidth-1 preventing it from ever being equal or greater than BitWidth.

At one point in the past the getLimitedValue call was only passed BitWidth not BitWidth - 1. This would have allowed the equality case to get here. And in fact this check was initially added as just BitWidth == ShiftAmt, but was changed shortly after to include > which should have never been possible.

Reviewers: spatel, majnemer, davide

Reviewed By: davide

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D36123

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@309690 91177308-0d34-0410-b5e6-96231b3b80d8
2017-08-01 15:10:25 +00:00
Craig Topper
279ac88b99 [InstCombine] Move (0 - x) & 1 --> x & 1 to SimplifyDemandedUseBits.
This removes a dedicated matcher and allows us to support more than just an AND masking the lower bit.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@308124 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-16 05:37:58 +00:00
Craig Topper
f552e96e02 [InstCombine] Make InstCombine's IRBuilder be passed by reference everywhere
Previously the InstCombiner class contained a pointer to an IR builder that had been passed to the constructor. Sometimes this would be passed to helper functions as either a pointer or the pointer would be dereferenced to be passed by reference.

This patch makes it a reference everywhere including the InstCombiner class itself so there is more inconsistency. This a large, but mechanical patch. I've done very minimal formatting changes on it despite what clang-format wanted to do.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@307451 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-07 23:16:26 +00:00
Craig Topper
6dbd34d261 [Constants] If we already have a ConstantInt*, prefer to use isZero/isOne/isMinusOne instead of isNullValue/isOneValue/isAllOnesValue inherited from Constant. NFCI
Going through the Constant methods requires redetermining that the Constant is a ConstantInt and then calling isZero/isOne/isMinusOne.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@307292 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-06 18:39:47 +00:00
Craig Topper
eb370b4757 [InstCombine][InstSimplify] Use APInt::isNullValue/isOneValue to reduce compiled code for comparing APInts with 0 and 1. NFC
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
2017-06-07 07:40:37 +00:00
Craig Topper
35596590b5 [InstCombine] Merge together the SimplifyDemandedUseBits implementations for ZExt and Trunc. NFC
While there avoid resizing the DemandedMask twice. Make a copy into a separate variable instead. This potentially removes an allocation on large bit widths.

With the use of the zextOrTrunc methods on APInt and KnownBits these can be made almost source identical. The only difference is the zero of the upper bits for ZExt. This is similar to how its done in computeKnownBits in ValueTracking.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303791 91177308-0d34-0410-b5e6-96231b3b80d8
2017-05-24 18:40:25 +00:00
Craig Topper
a9efa93362 [InstCombine] Use less bitwise operations to handle Instruction::SExt in SimplifyDemandedUseBits. Other improvements.
The current code created a NewBits mask and used it as a mask several times. One of them just before a call to trunc making it unnecessary. A call to getActiveBits can get us the same information for the case. We also ORed with this mask later when we should have just sign extended the known bits.

We also called trunc on the guaranteed to be zero KnownZeros/Ones masks entering this code. Creating appropriately sized temporary APInts is probably better.

Differential Revision: https://reviews.llvm.org/D32098

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303779 91177308-0d34-0410-b5e6-96231b3b80d8
2017-05-24 17:33:30 +00:00
Craig Topper
5e9f2d0f5d [KnownBits] Use !hasConflict() in asserts in place of Zero & One == 0 or similar. NFC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303614 91177308-0d34-0410-b5e6-96231b3b80d8
2017-05-23 07:18:37 +00:00
Craig Topper
d49344495d [KnownBits] Add bit counting methods to KnownBits struct and use them where possible
This patch adds min/max population count, leading/trailing zero/one bit counting methods.

The min methods return answers based on bits that are known without considering unknown bits. The max methods give answers taking into account the largest count that unknown bits could give.

Differential Revision: https://reviews.llvm.org/D32931

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@302925 91177308-0d34-0410-b5e6-96231b3b80d8
2017-05-12 17:20:30 +00:00
Craig Topper
ace8b39f82 [KnownBits] Add wrapper methods for setting and clear all bits in the underlying APInts in KnownBits.
This adds routines for reseting KnownBits to unknown, making the value all zeros or all ones. It also adds methods for querying if the value is zero, all ones or unknown.

Differential Revision: https://reviews.llvm.org/D32637

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@302262 91177308-0d34-0410-b5e6-96231b3b80d8
2017-05-05 17:36:09 +00:00
Craig Topper
f78221855b [KnownBits] Add zext, sext, and trunc methods to KnownBits
This patch adds zext, sext, and trunc methods to KnownBits and uses them where possible.

Differential Revision: https://reviews.llvm.org/D32784

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@302088 91177308-0d34-0410-b5e6-96231b3b80d8
2017-05-03 22:07:25 +00:00
Craig Topper
8b69610574 [KnownBits] Add methods for determining if the known bits represent a negative/nonnegative number and add methods for changing the negative/nonnegative state
Summary: This patch adds isNegative, isNonNegative for querying whether the sign bit is known. It also adds makeNegative and makeNonNegative for controlling the sign bit.

Reviewers: RKSimon, spatel, davide

Reviewed By: RKSimon

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D32651

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@301747 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-29 16:43:11 +00:00
Craig Topper
a7fa95c0e5 [APInt] Use inplace shift methods where possible. NFCI
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@301612 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-28 03:36:24 +00:00
Craig Topper
58c7fe69d0 [ValueTracking] Introduce a KnownBits struct to wrap the two APInts for computeKnownBits
This patch introduces a new KnownBits struct that wraps the two APInt used by computeKnownBits. This allows us to treat them as more of a unit.

Initially I've just altered the signatures of computeKnownBits and InstCombine's simplifyDemandedBits to pass a KnownBits reference instead of two separate APInt references. I'll do similar to the SelectionDAG version of computeKnownBits/simplifyDemandedBits as a separate patch.

I've added a constructor that allows initializing both APInts to the same bit width with a starting value of 0. This reduces the repeated pattern of initializing both APInts. Once place default constructed the APInts so I added a default constructor for those cases.

Going forward I would like to add more methods that will work on the pairs. For example trunc, zext, and sext occur on both APInts together in several places. We should probably add a clear method that can be used to clear both pieces. Maybe a method to check for conflicting information. A method to return (Zero|One) so we don't write it out everywhere. Maybe a method for (Zero|One).isAllOnesValue() to determine if all bits are known. I'm sure there are many other methods we can come up with.

Differential Revision: https://reviews.llvm.org/D32376

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@301432 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-26 16:39:58 +00:00
Craig Topper
21db70eaca [APInt] Use isSubsetOf, intersects, and bit counting methods to reduce temporary APInts
This patch uses various APInt methods to reduce temporary APInt creation.

This should be all of the unrelated cleanups that got buried in D32376(creating a KnownBits struct) as well as some pointed out by Simon during the review of that. Plus a few improvements to use counting instead of masking.

I've left out any places where we do something like (KnownZero & KnownOne) != 0 as I plan to add a helper method to KnownBits to ask that question and didn't want to thrash that code an additional time.

Differential Revision: https://reviews.llvm.org/D32495

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@301338 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-25 17:46:30 +00:00
Craig Topper
65c40b4fba [InstCombine] Remove superfluous curly braces around a single line if body. NFC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@301326 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-25 16:48:19 +00:00
Renato Golin
d907744fff Revert "[APInt] Fix a few places that use APInt::getRawData to operate within the normal API."
This reverts commit r301105, 4, 3 and 1, as a follow up of the previous
revert, which broke even more bots.

For reference:
Revert "[APInt] Use operator<<= where possible. NFC"
Revert "[APInt] Use operator<<= instead of shl where possible. NFC"
Revert "[APInt] Use ashInPlace where possible."

PR32754.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@301111 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-23 12:15:30 +00:00
Craig Topper
5e17d2e85c [APInt] Use operator<<= instead of shl where possible. NFC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@301103 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-23 05:18:31 +00:00
Sanjay Patel
b51ea00f00 [InstCombine] revert r300977 and r301021
This can cause an inf-loop. Investigating...


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@301035 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-21 20:29:17 +00:00
Sanjay Patel
39af0db425 [InstCombine] use isSubsetOf() for efficiency
C | ~D == -1
~(C | ~D) == 0
~C & D == 0
D & ~C == 0
D.isSubsetOf(C)



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@301021 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-21 19:16:52 +00:00
Sanjay Patel
bd1b03d467 [InstCombine] prefer xor with -1 because 'not' is easier to understand (PR32706)
This matches the demanded bits behavior in the DAG and should fix:
https://bugs.llvm.org/show_bug.cgi?id=32706

Differential Revision: https://reviews.llvm.org/D32255


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300977 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-21 14:03:54 +00:00
Craig Topper
c7e3512b43 [InstCombine] Remove the zextOrTrunc from ShrinkDemandedConstant.
The demanded mask and the constant should always be the same width for all callers today.

Also stop copying the demanded mask as its passed in. We should avoid allocating memory unless we are going to do something. The final AND to create the new constant will take care of it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300927 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-20 23:58:27 +00:00
Sanjay Patel
f23a493cab [InstCombine] function names start with lower-case letter; NFC
Forgot to make this fix with the signature change in r300911.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300912 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-20 22:37:01 +00:00
Sanjay Patel
e29c6aab81 [InstCombine] allow shl+shr demanded bits folds with splat constants
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300911 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-20 22:33:54 +00:00
Sanjay Patel
a24f137360 [InstCombine] allow shl demanded bits folds with splat constants
More fixes are needed to enable the helper SimplifyShrShlDemandedBits().



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300898 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-20 21:33:02 +00:00
Craig Topper
7b99ac1139 [InstCombine] Use APInt::intersects and APInt::isSubsetOf to improve a few more places in SimplifyDemandedBits.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300896 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-20 21:24:37 +00:00
Sanjay Patel
f0d51838c5 [InstCombine] allow ashr/lshr demanded bits folds with splat constants
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300888 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-20 20:59:02 +00:00
Craig Topper
a6180c4b3c [InstCombine] Use APInt::isSubsetOf to simplify some code in SimplifyDemandedBits. NFC
This allows us to use less temporary APInt for And and Invert operations.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300885 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-20 20:47:35 +00:00
Craig Topper
1fa7ca8b26 [InstCombine] Remove redundant code from SimplifyDemandedBits handling for Or. The code above it is equivalent if you work through the bitwise math.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300876 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-20 19:31:22 +00:00
Craig Topper
54f0462d2b [APInt] Rename getSignBit to getSignMask
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
2017-04-20 16:56:25 +00:00
Craig Topper
b52e0e4247 [APInt] Add isSubsetOf method that can check if one APInt is a subset of another without creating temporary APInts
This question comes up in many places in SimplifyDemandedBits. This makes it easy to ask without allocating additional temporary APInts.

The BitVector class provides a similar functionality through its (IMHO badly named) test(const BitVector&) method. Though its output polarity is reversed.

I've provided one example use case in this patch. I plan to do more as a follow up.

Differential Revision: https://reviews.llvm.org/D32258



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300851 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-20 16:17:13 +00:00
Craig Topper
1772e90779 In SimplifyDemandedUseBits, use computeKnownBits directly to handle Constants
Currently we don't explicitly process ConstantDataSequential, ConstantAggregateZero, or ConstantVector, or Undef before applying the Depth limit. Instead they occur after the depth check in the non-instruction path.

For the constant types that we do handle, the code is replicated from computeKnownBits.

This patch fixes the missing constant handling and the reduces the amount of code by just using computeKnownBits directly for any type of Constant.

Differential Revision: https://reviews.llvm.org/D32123



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300849 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-20 16:14:58 +00:00
Craig Topper
df22034939 [APInt] Use lshrInPlace to replace lshr where possible
This patch uses lshrInPlace to replace code where the object that lshr is called on is being overwritten with the result.

This adds an lshrInPlace(const APInt &) version as well.

Differential Revision: https://reviews.llvm.org/D32155




git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300566 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-18 17:14:21 +00:00