Merging r222338:
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r222338 | majnemer | 2014-11-19 01:41:05 -0800 (Wed, 19 Nov 2014) | 16 lines

AliasSetTracker: UnknownInsts should contribute to the refcount

AliasSetTracker::addUnknown may create an AliasSet devoid of pointers
just to contain an instruction if no suitable AliasSet already exists.
It will then AliasSet::addUnknownInst and we will be done.

However, it's possible for addUnknown to choose an existing AliasSet to
addUnknownInst.
If this were to occur, we are in a bit of a pickle: removing pointers
from the AliasSet can cause the entire AliasSet to become destroyed,
taking our unknown instructions out with them.

Instead, keep track whether or not our AliasSet has any unknown
instructions.

This fixes PR21582.
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git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_35@223627 91177308-0d34-0410-b5e6-96231b3b80d8
Merging rr222376:
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r222376 | majnemer | 2014-11-19 11:36:18 -0800 (Wed, 19 Nov 2014) | 3 lines

AliasSet: Simplify mergeSetIn

No functional change intended.
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git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_35@223635 91177308-0d34-0410-b5e6-96231b3b80d8
Merging rr221501:
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r221501 | majnemer | 2014-11-06 16:31:14 -0800 (Thu, 06 Nov 2014) | 7 lines

LoopVectorize: Don't assume pointees are sized

A pointer's pointee might not be sized: the pointee could be a function.

Report this as IK_NoInduction when calculating isInductionVariable.

This fixes PR21508.
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Merging rr217102:
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r217102 | majnemer | 2014-09-03 16:03:18 -0700 (Wed, 03 Sep 2014) | 11 lines

IndVarSimplify: Don't let LFTR compare against a poison value

LinearFunctionTestReplace tries to use the *next* indvar to compare
against when possible.  However, it may be the case that the calculation
for the next indvar has NUW/NSW flags and that it may only be safely
used inside the loop.  Using it in a comparison to calculate the exit
condition could result in observing poison.

This fixes PR20680.

Differential Revision: http://reviews.llvm.org/D5174
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git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_35@223637 91177308-0d34-0410-b5e6-96231b3b80d8
Merging r217115:
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r217115 | majnemer | 2014-09-03 17:23:13 -0700 (Wed, 03 Sep 2014) | 3 lines

IndVarSimplify: Address review comments for r217102

No functional change intended, just some cleanups and comments added.
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git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_35@223638 91177308-0d34-0410-b5e6-96231b3b80d8
Merging r216891:
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r216891 | majnemer | 2014-09-01 14:20:14 -0700 (Mon, 01 Sep 2014) | 12 lines

SROA: Don't insert instructions before a PHI

SROA may decide that it needs to insert a bitcast and would set it's
insertion point before a PHI.  This will create an invalid module
right quick.

Instead, choose the first insertion point in the basic block that holds
our PHI.

This fixes PR20822.

Differential Revision: http://reviews.llvm.org/D5141
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Merging r222500:
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r222500 | majnemer | 2014-11-20 18:37:38 -0800 (Thu, 20 Nov 2014) | 1 line

This Reassociate change unintentionally slipped in r222499
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Fix merge conflict & minor test output differences


git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_35@223643 91177308-0d34-0410-b5e6-96231b3b80d8
Merging r214385:
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r214385 | majnemer | 2014-07-30 21:49:29 -0700 (Wed, 30 Jul 2014) | 9 lines

InstCombine: Correctly propagate NSW/NUW for x-(-A) -> x+A

We can only propagate the nsw bits if both subtraction instructions are
marked with the appropriate bit.

N.B.  We only propagate the nsw bit in InstCombine because the nuw case
is already handled in InstSimplify.

This fixes PR20189.
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Merging r215818:
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r215818 | majnemer | 2014-08-16 02:23:42 -0700 (Sat, 16 Aug 2014) | 12 lines

InstCombine: Fix a potential bug in 0 - (X sdiv C)  -> (X sdiv -C)

While *most* (X sdiv 1) operations will get caught by InstSimplify, it
is still possible for a sdiv to appear in the worklist which hasn't been
simplified yet.

This means that it is possible for 0 - (X sdiv 1) to get transformed
into (X sdiv -1); dividing by -1 can make the transform produce undef
values instead of the proper result.

Sorry for the lack of testcase, it's a bit problematic because it relies
on the exact order of operations in the worklist.
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git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_35@223645 91177308-0d34-0410-b5e6-96231b3b80d8
I did not intend to merge these in.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_35@223646 91177308-0d34-0410-b5e6-96231b3b80d8
Merging r221318:
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r221318 | majnemer | 2014-11-04 15:49:08 -0800 (Tue, 04 Nov 2014) | 10 lines

Analysis: Make isSafeToSpeculativelyExecute fire less for divides

Divides and remainder operations do not behave like other operations
when they are given poison: they turn into undefined behavior.

It's really hard to know if the operands going into a div are or are not
poison.  Because of this, we should only choose to speculate if there
are constant operands which we can easily reason about.

This fixes PR21412.
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