2217 Commits

Author SHA1 Message Date
Sanjay Patel
2aa6ae886a [DAG] add splat vector support for 'or' in SimplifyDemandedBits
I've changed one of the tests to not fold away, but we didn't and still don't do the transform
that the comment claims we do (and I don't know why we'd want to do that).

Follow-up to:
https://reviews.llvm.org/rL300725
https://reviews.llvm.org/rL300763


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300772 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-19 22:00:00 +00:00
Sanjay Patel
27b613382c [DAG] add splat vector support for 'xor' in SimplifyDemandedBits
This allows forming more 'not' ops, so we get improvements for ISAs that have and-not.

Follow-up to:
https://reviews.llvm.org/rL300725


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300763 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-19 21:23:09 +00:00
Sanjay Patel
14ee3d3d79 [DAG] add splat vector support for 'and' in SimplifyDemandedBits
The patch itself is simple: stop discriminating against vectors in visitAnd() and again in 
SimplifyDemandedBits().

Some notes for reference:

1. We're not consistent about calls to SimplifyDemandedBits in the various visitXXX functions. 
   Sometimes, we check if the RHS is a constant first. Other times (like here), we just dive in.
2. I'd like to break the vector shackles in steps for the sake of risk minimization, but we could
    make similar simultaneous changes in other places if we think that would be better.
3. I don't know what the intent of the changed tests in this patch was supposed to be, but since 
   they wiggled in a positive way, I'm just going with that. :)
4. In the rotate tests, note that we can see through non-splat constants. This is a result of D24253.
5. My motivation for being here now is to make D31944 look better, so this is step 1 of N towards 
   improving the vector codegen in that patch without writing any actual new code.

Differential Revision: https://reviews.llvm.org/D32230


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300725 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-19 18:05:06 +00:00
Nirav Dave
e874e43854 [DAG] Loop over remaining candidates on successful merge of stores of
extracted vectors types. NFCI.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300688 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-19 13:52:38 +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
Nirav Dave
e77d07916e [DAG] Improve store merge candidate pruning.
Remove non-consecutive stores from store merge candidate search as
they cannot be merged and will prevent us from finding subsequent
mergeable store cases.

Reviewers: jyknight, bogner, javed.absar, spatel

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D32086

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300561 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-18 15:36:34 +00:00
Nirav Dave
ede58cd844 Reorder StoreMergeCandidates to run faster. NFCI.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300321 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-14 13:34:30 +00:00
Nirav Dave
042486c448 [DAG] Fold away temporary vector in store candidate merge NFC.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300241 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-13 20:00:27 +00:00
Nirav Dave
020cbfba48 [SDAG] Factor CandidateMatch check into lambda. NFC.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@299939 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-11 13:41:19 +00:00
Nirav Dave
da18b45fd0 [SDAG] Factor ChainMerge into helper function NFCI.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@299938 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-11 13:41:17 +00:00
Nirav Dave
5074c86cc6 [SDAG] Reorder expensive StoreMerge Check after cheaper one. NFC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@299937 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-11 13:41:16 +00:00
Nirav Dave
d4d2ab353e [SDAG] Fix visitAND optimization to deal with vector extract case again.
Summary:
Fix case elided by rL298920.

Fixes PR32545.

Reviewers: eli.friedman, RKSimon

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D31759

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@299688 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-06 19:05:41 +00:00
Adam Nemet
c0a481413e [DAGCombine] Support FMF contract in fused multiple-and-sub too
This is a follow-on to r299096 which added support for fmadd.

Subtract does not have the case where with two multiply operands we commute in
order to fuse with the multiply with the fewer uses.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@299572 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-05 17:58:48 +00:00
Adam Nemet
0a518c38de [DAGCombine] Remove commented-out code from r299096
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@299571 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-05 17:58:44 +00:00
Sanjay Patel
a070c921e5 [DAGCombiner] add and use TLI hook to convert and-of-seteq / or-of-setne to bitwise logic+setcc (PR32401)
This is a generic combine enabled via target hook to reduce icmp logic as discussed in:
https://bugs.llvm.org/show_bug.cgi?id=32401

It's likely that other targets will want to enable this hook for scalar transforms, 
and there are probably other patterns that can use bitwise logic to reduce comparisons.

Note that we are missing an IR canonicalization for these patterns, and we will probably
prefer the pair-of-compares form in IR (shorter, more likely to fold).

Differential Revision: https://reviews.llvm.org/D31483



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@299542 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-05 14:09:39 +00:00
Craig Topper
445d3cfd6b [DAGCombine][InstCombine] Fix inverted if condition in equivalent comments in DAGCombine and InstCombine. NFC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@299378 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-03 19:18:48 +00:00
Zvi Rackover
f60f35be0a Revert "[DAGCombine] A shuffle of a splat is always the splat itself"
This reverts commit r299047 which is incorrect because the
simplification may result in incorrect propogation of undefs to users of
the folded shuffle.

Thanks to Andrea Di Biagio for pointing this out.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@299368 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-03 17:41:19 +00:00
Craig Topper
68149f546e [APInt] Move isMask and isShiftedMask out of APIntOps and into the APInt class. Implement them without memory allocation for multiword
This moves the isMask and isShiftedMask functions to be class methods. They now use the MathExtras.h function for single word size and leading/trailing zeros/ones or countPopulation for the multiword size. The previous implementation made multiple temorary memory allocations to do the bitwise arithmetic operations to match the MathExtras.h implementation.

Differential Revision: https://reviews.llvm.org/D31565




git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@299362 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-03 16:34:59 +00:00
Simon Pilgrim
3c078c1589 [DAGCombiner] Check limits before accessing array element (PR32502)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@299361 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-03 15:27:49 +00:00
Sanjay Patel
c2d4aab4d9 [DAGCombiner] enable vector transforms for any/all {sign} bits set/clear
The code already allowed vector types in via "isInteger" (which might want
a more specific name), so use splat-friendly constant predicates to match
those types.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@299304 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-01 15:05:54 +00:00
Craig Topper
0c554b7eb1 [DAGCombiner] Fix fold (or (shuf A, V_0, MA), (shuf B, V_0, MB)) -> (shuf A, B, Mask) to explicitly ensure that only one of the inputs of each shuffle is a zero vector.
This can only happen when we have a mix of zero and undef elements and the two vectors have a different arrangement of zeros/undefs. The shuffle should eventually be constant folded to all zeros.

Fixes PR32484.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@299291 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-01 04:26:20 +00:00
Sanjay Patel
e44ee41b80 [DAGCombiner] refactor and/or-of-setcc to get rid of duplicated code; NFCI
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@299266 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-31 21:30:50 +00:00
Sanjay Patel
0f0cd01471 [DAGCombiner] add fold for 'All sign bits set?'
(and (setlt X,  0), (setlt Y,  0)) --> (setlt (and X, Y),  0)

We have 7 similar folds, but this one got away. The fact that the
x86 test with a branch didn't change is probably a separate bug. We
may also be missing this and the related folds in instcombine.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@299252 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-31 20:28:06 +00:00
Sanjay Patel
d1c650cbed [DAGCombiner] remove redundant code and add comments; NFCI
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@299241 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-31 18:18:58 +00:00
Adam Nemet
1042cb40de [DAGCombiner] Initial support for the fast-math flag contract
Now alternatively to the TargetOption.AllowFPOpFusion global flag, FMUL->FADD
can also use the per operation FMF to allow fusion.

The idea here is not to port everything to the new scheme (e.g. fused
multiply-and-sub will be ported later) but that this work all the way from
clang.

The transformation is conditionalized on *both* the FADD and the FMUL having
the FMF contract flag.

Differential Revision: https://reviews.llvm.org/D31169

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@299096 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-30 18:53:04 +00:00
Sanjay Patel
af5759db47 [DAGCombiner] add helper function for visitORLike; NFCI
This combines all of the equivalent clean-ups for foldAndOfSetCCs:
https://reviews.llvm.org/rL298938
https://reviews.llvm.org/rL298940
https://reviews.llvm.org/rL298944
https://reviews.llvm.org/rL298949
https://reviews.llvm.org/rL298950
https://reviews.llvm.org/rL299002
https://reviews.llvm.org/rL299013

The sins of code duplication are on full display here:
each function is missing a fold that wasn't copied over from its logical sibling. 


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@299091 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-30 17:32:42 +00:00
Zvi Rackover
2f7335804b [DAGCombine] A shuffle of a splat is always the splat itself
Summary:
Add a simplification:
shuffle (splat-shuffle), undef, M --> splat-shuffle

Fixes pr32449

Patch by Sanjay Patel

Reviewers: eli.friedman, RKSimon, spatel

Reviewed By: spatel

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D31426

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@299047 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-30 01:42:57 +00:00
Davide Italiano
64abec8d56 [DAGCombiner] Remove else after return. NFCI.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@299022 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-29 19:39:46 +00:00
Sanjay Patel
37cb59fa3b [DAGCombiner] unify type checks and add asserts; NFCI
We had a mix of type checks and usage that wasn't very clear.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@299013 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-29 18:08:01 +00:00
Sanjay Patel
aa3cce33cc [DAGCombiner] reduce code duplication by rearranging checks; NFCI
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@299002 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-29 15:37:33 +00:00
Sanjay Patel
3a0175382a [DAGCombiner] reduce code duplication with local variables; NFCI
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@298954 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-28 22:45:53 +00:00
Sanjay Patel
8cc66a64a3 [DAGCombiner] remove redundant conditions and duplicated code; NFCI
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@298949 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-28 22:22:50 +00:00
Sanjay Patel
f54b836e26 [DAGCombiner] rename variables in foldAndOfSetCCs for easier reading; NFCI
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@298944 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-28 21:40:41 +00:00
Sanjay Patel
3812900a6d [DAGCombiner] clean up foldAndOfSetCCs; NFCI
1. Fix bogus comment.
2. Early exit to reduce indent.
3. Change node pointer param to what it really is: an SDLoc.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@298940 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-28 20:28:16 +00:00
Sanjay Patel
d707b92e85 [DAGCombiner] add helper function for and-of-setcc folds; NFC
This is just a cut and paste followed by clang-format. Clean up to follow.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@298938 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-28 19:58:46 +00:00
Nirav Dave
f92edffeda [SDAG] Deal with deleted node in PromoteIntShiftOp
Deal with case that initial node is deleted during dag-combine leading
to an assertional failure in promoteIntShiftOp.

Fixes PR32420.

Reviewers: spatel, RKSimon

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D31403

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@298931 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-28 17:09:49 +00:00
Nirav Dave
227a06d5bb [SDAG] Avoid deleted SDNodes PromoteIntBinOp
Reorder work in PromoteIntBinOp to prevent stale (deleted) nodes from
being used.

Fixes PR32340 and PR32345.

Reviewers: hfinkel, dbabokin

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D31148

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@298923 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-28 15:41:12 +00:00
Nirav Dave
5dc2b58301 [SDAG] Fix Stale SDNode usage in visitAND
Reorder CombineTo Calls to prevent potential use of deleted node.
Fixes PR32372.

Reviewers: jnspaulsson, RKSimon, uweigand, jonpa

Reviewed By: jonpa

Subscribers: jonpa, llvm-commits

Differential Revision: https://reviews.llvm.org/D31346

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@298920 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-28 14:11:20 +00:00
Nirav Dave
e6987121ba [SDAG] Minor cleanup of variable usage. NFC.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@298916 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-28 13:39:50 +00:00
Nirav Dave
ed770d47a5 [SDAG] Fix zeroExtend assertion error
Move CombineTo preventing deleted node from being returned in
visitZERO_EXTEND.

Fixes PR32284.

Reviewers: RKSimon, bogner

Reviewed By: RKSimon

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D31254

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@298604 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-23 15:01:50 +00:00
Reid Kleckner
6707770d48 Rename AttributeSet to AttributeList
Summary:
This class is a list of AttributeSetNodes corresponding the function
prototype of a call or function declaration. This class used to be
called ParamAttrListPtr, then AttrListPtr, then AttributeSet. It is
typically accessed by parameter and return value index, so
"AttributeList" seems like a more intuitive name.

Rename AttributeSetImpl to AttributeListImpl to follow suit.

It's useful to rename this class so that we can rename AttributeSetNode
to AttributeSet later. AttributeSet is the set of attributes that apply
to a single function, argument, or return value.

Reviewers: sanjoy, javed.absar, chandlerc, pete

Reviewed By: pete

Subscribers: pete, jholewinski, arsenm, dschuff, mehdi_amini, jfb, nhaehnle, sbc100, void, llvm-commits

Differential Revision: https://reviews.llvm.org/D31102

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@298393 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-21 16:57:19 +00:00
Matt Arsenault
0597e5e3b0 DAG: Fold bitcast/extract_vector_elt of undef to undef
Fixes not eliminating store when intrinsic is lowered to undef.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@298385 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-21 16:20:16 +00:00
Jonas Paulsson
1b6f5a39a9 [SelectionDAG] Optimize VSELECT->SETCC of incompatible or illegal types.
Don't scalarize VSELECT->SETCC when operands/results needs to be widened,
or when the type of the SETCC operands are different from those of the VSELECT.

(VSELECT SETCC) and (VSELECT (AND/OR/XOR (SETCC,SETCC))) are handled.

The previous splitting of VSELECT->SETCC in DAGCombiner::visitVSELECT() is
no longer needed and has been removed.

Updated tests:

test/CodeGen/ARM/vuzp.ll
test/CodeGen/NVPTX/f16x2-instructions.ll
test/CodeGen/X86/2011-10-19-widen_vselect.ll
test/CodeGen/X86/2011-10-21-widen-cmp.ll
test/CodeGen/X86/psubus.ll
test/CodeGen/X86/vselect-pcmp.ll

Review: Eli Friedman, Simon Pilgrim
https://reviews.llvm.org/D29489

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@297930 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-16 07:17:12 +00:00
Zvi Rackover
184011252a [DAGCombine] Bail out if can't create a vector with at least two elements
Summary:

Fixes pr32278

Reviewers: igorb, craig.topper, RKSimon, spatel, hfinkel

Reviewed By: RKSimon

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D30978

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@297878 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-15 19:48:36 +00:00
Simon Pilgrim
e35265b998 [SelectionDAG] Add a signed integer absolute ISD node
Reduced version of D26357 - based on the discussion on llvm-dev about canonicalization of UMIN/UMAX/SMIN/SMAX as well as ABS I've reduced that patch to just the ABS ISD node (with x86/sse support) to improve basic combines and lowering.

ARM/AArch64, Hexagon, PowerPC and NVPTX all have similar instructions allowing us to make this a generic opcode and move away from the hard coded tablegen patterns which makes it tricky to match more complex patterns.

At the moment this patch doesn't attempt legalization as we only create an ABS node if its legal/custom.

Differential Revision: https://reviews.llvm.org/D29639

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@297780 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-14 21:26:58 +00:00
Sanjay Patel
bea559baff [DAG] vector div/rem with any zero element in divisor is undef
This is the backend counterpart to:
https://reviews.llvm.org/rL297390
https://reviews.llvm.org/rL297409
and follow-up to:
https://reviews.llvm.org/rL297384

It surprised me that we need to duplicate the check in FoldConstantArithmetic and FoldConstantVectorArithmetic, 
but one or the other doesn't catch all of the test cases. There is an existing code comment about merging those 
someday.

Differential Revision: https://reviews.llvm.org/D30826


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@297762 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-14 18:06:28 +00:00
Nirav Dave
3bbf394145 In visitSTORE, always use FindBetterChain, rather than only when UseAA is enabled.
Recommiting with compiler time improvements

    Recommitting after fixup of 32-bit aliasing sign offset bug in DAGCombiner.

    * Simplify Consecutive Merge Store Candidate Search

    Now that address aliasing is much less conservative, push through
    simplified store merging search and chain alias analysis which only
    checks for parallel stores through the chain subgraph. This is cleaner
    as the separation of non-interfering loads/stores from the
    store-merging logic.

    When merging stores search up the chain through a single load, and
    finds all possible stores by looking down from through a load and a
    TokenFactor to all stores visited.

    This improves the quality of the output SelectionDAG and the output
    Codegen (save perhaps for some ARM cases where we correctly constructs
    wider loads, but then promotes them to float operations which appear
    but requires more expensive constant generation).

    Some minor peephole optimizations to deal with improved SubDAG shapes (listed below)

    Additional Minor Changes:

      1. Finishes removing unused AliasLoad code

      2. Unifies the chain aggregation in the merged stores across code
         paths

      3. Re-add the Store node to the worklist after calling
         SimplifyDemandedBits.

      4. Increase GatherAllAliasesMaxDepth from 6 to 18. That number is
         arbitrary, but seems sufficient to not cause regressions in
         tests.

      5. Remove Chain dependencies of Memory operations on CopyfromReg
         nodes as these are captured by data dependence

      6. Forward loads-store values through tokenfactors containing
          {CopyToReg,CopyFromReg} Values.

      7. Peephole to convert buildvector of extract_vector_elt to
         extract_subvector if possible (see
         CodeGen/AArch64/store-merge.ll)

      8. Store merging for the ARM target is restricted to 32-bit as
         some in some contexts invalid 64-bit operations are being
         generated. This can be removed once appropriate checks are
         added.

    This finishes the change Matt Arsenault started in r246307 and
    jyknight's original patch.

    Many tests required some changes as memory operations are now
    reorderable, improving load-store forwarding. One test in
    particular is worth noting:

      CodeGen/PowerPC/ppc64-align-long-double.ll - Improved load-store
      forwarding converts a load-store pair into a parallel store and
      a memory-realized bitcast of the same value. However, because we
      lose the sharing of the explicit and implicit store values we
      must create another local store. A similar transformation
      happens before SelectionDAG as well.

    Reviewers: arsenm, hfinkel, tstellarAMD, jyknight, nhaehnle

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@297695 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-14 00:34:14 +00:00
Amaury Sechet
2cab1ec06e [DAGCombiner] Do various combine on uaddo.
Summary: This essentially does the same transform as for ADC.

Reviewers: jyknight, nemanjai, mkuper, spatel, RKSimon, zvi, bkramer

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D30417

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@297416 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-09 22:47:00 +00:00
Amaury Sechet
f15775bffb [DAGCombiner] Do various combine on usubo.
Summary: This essentially does the same transform as for SUBC.

Reviewers: jyknight, nemanjai, mkuper, spatel, RKSimon, zvi, bkramer

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D30437

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@297404 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-09 19:28:00 +00:00
Sanjay Patel
4f7ea50478 [DAG] recognize div/rem by 0 as undef before trying constant folding
As discussed in the review thread for rL297026, this is actually 2 changes that 
would independently fix all of the test cases in the patch:

1. Return undef in FoldConstantArithmetic for div/rem by 0.
2. Move basic undef simplifications for div/rem (simplifyDivRem()) before 
   foldBinopIntoSelect() as a matter of efficiency.

I will handle the case of vectors with any zero element as a follow-up. That change
is the DAG sibling for D30665 + adding a check of vector elements to FoldConstantVectorArithmetic().

I'm deleting the test for PR30693 because it does not test for the actual bug any more
(dangers of using bugpoint).

Differential Revision:
https://reviews.llvm.org/D30741


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@297384 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-09 15:02:25 +00:00