Commit Graph

11724 Commits

Author SHA1 Message Date
Erik Eckstein
5e2214cca6 SLPVectorizer: fix build problem in Release configuration
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214496 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-01 09:47:38 +00:00
Erik Eckstein
956268f9dc SLPVectorizer: improved scheduling algorithm.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214494 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-01 09:20:42 +00:00
Erik Eckstein
12f7582cf0 SLP Vectorizer: added statistics counter
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214487 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-01 08:14:28 +00:00
Erik Eckstein
e47fce60e4 SLP Vectorizer: improve canonicalize tree operands of commutitive binary operands.
This reverts r214338 (except the test file) and replaces it with a more general algorithm.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214485 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-01 08:05:55 +00:00
Suyog Sarda
1952b5a4da This patch implements transform for pattern "(A & ~B) ^ (~A) -> ~(A & B)".
Differential Revision: http://reviews.llvm.org/D4653



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214479 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-01 05:07:20 +00:00
Suyog Sarda
78061f4db4 This patch implements transform for pattern "(A | B) & ((~A) ^ B) -> (A & B)".
Differential Revision: http://reviews.llvm.org/D4628



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214478 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-01 04:59:26 +00:00
Suyog Sarda
d05b6c6f2c This patch implements transform for pattern "( A & (~B)) | (A ^ B) -> (A ^ B)"
Differential Revision: http://reviews.llvm.org/D4652



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214477 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-01 04:50:31 +00:00
Suyog Sarda
87569413b0 This patch implements transform for pattern "(A & B) | ((~A) ^ B) -> (~A ^ B)".
Patch Credit to Ankit Jain !

Differential Revision: http://reviews.llvm.org/D4655



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214476 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-01 04:41:43 +00:00
Tyler Nowicki
f7be7f15c1 Improve the remark generated for -Rpass-missed.
The current remark is ambiguous and makes it sounds like explicitly specifying vectorization will allow the loop to be vectorized. This is not the case. The improved remark directs the user to -Rpass-analysis=loop-vectorize to determine the cause of the pass-miss.

Reviewed by Arnold Schwaighofer`


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214445 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-31 21:22:22 +00:00
Tyler Nowicki
88212074a8 Improve the remark generated when a variable that is used outside the loop is not a reduction or induction variable.
Reviewed by Arnold Schwaighofer


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214440 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-31 21:02:40 +00:00
Evgeniy Stepanov
7ee4f09c94 [msan] Fix handling of array types.
Switch array type shadow from a single integer to
an array of integers (i.e. make it per-element).
This simplifies instrumentation of extractvalue and fixes PR20493.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214398 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-31 11:02:27 +00:00
Stepan Dyatkovskiy
40f2023d33 MergeFunctions, tiny refactoring:
cmpOperation has been renamed to cmpOperations (multiple form).



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214392 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-31 07:16:59 +00:00
David Majnemer
a4a812fedd 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.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214385 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-31 04:49:29 +00:00
David Majnemer
5624046453 InstCombine: Simplify (A ^ B) or/and (A ^ B ^ C)
While we can already transform A | (A ^ B) into A | B, things get bad
once we have (A ^ B) | (A ^ B ^ Cst) because reassociation will morph
this into (A ^ B) | ((A ^ Cst) ^ B).  Our existing patterns fail once
this happens.

To fix this, we add a new pattern which looks through the tree of xor
binary operators to see that, in fact, there exists a redundant xor
operation.

What follows bellow is a correctness proof of the transform using CVC3.

$ cat t.cvc
A, B, C : BITVECTOR(64);

QUERY BVXOR(A, B) | BVXOR(BVXOR(B, C), A) = BVXOR(A, B) | C;
QUERY BVXOR(BVXOR(A, C), B) | BVXOR(A, B) = BVXOR(A, B) | C;

QUERY BVXOR(A, B) & BVXOR(BVXOR(B, C), A) = BVXOR(A, B) & ~C;
QUERY BVXOR(BVXOR(A, C), B) & BVXOR(A, B) = BVXOR(A, B) & ~C;

$ cvc3 < t.cvc
Valid.
Valid.
Valid.
Valid.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214342 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-30 21:26:37 +00:00
Chad Rosier
7f6a685444 SLP Vectorizer: Canonicalize tree operands of commutitive binary operands.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214338 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-30 21:07:56 +00:00
Rafael Espindola
7fef5a3d19 SimplifyCFG: Avoid miscompilations due to removed lifetime intrinsics.
The lifetime intrinsics need some work in order to make it clear which
optimizations are or are not valid.

For now dropping this optimization avoids a miscompilation.

Patch by Björn Steinbrink.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214336 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-30 21:04:00 +00:00
Aaron Ballman
75ba1b0ded Fixing a few -Woverloaded-virtual warnings by exposing the hidden virtual function as well. No functional changes intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214325 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-30 19:23:59 +00:00
Rafael Espindola
4366b6cede Add the missing hasLinkOnceODRLinkage predicate.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214312 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-30 15:57:51 +00:00
Manman Ren
807538b567 [Debug Info] add DISubroutineType and its creation takes DITypeArray.
DITypeArray is an array of DITypeRef, at its creation, we will create
DITypeRef (i.e use the identifier if the type node has an identifier).

This is the last patch to unique the type array of a subroutine type.

rdar://17628609


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214132 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-28 22:24:06 +00:00
Manman Ren
8e8c1ac702 [Debug Info] rename getTypeArray to getElements, setTypeArray to setArrays.
This is the second of a series of patches to handle type uniqueing of the
type array for a subroutine type.

For vector and array types, getElements returns the array of subranges, so it
is a better name than getTypeArray. Even for class, struct and enum types,
getElements returns the members, which can be subprograms.

setArrays can set up to two arrays, the second is the templates.

This commit should have no functionality change.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214112 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-28 19:14:13 +00:00
Hal Finkel
5cb8ab5b5a Canonicalization for @llvm.assume
Adds simple logical canonicalization of assumption intrinsics to instcombine,
currently:
 - invariant(a && b) -> invariant(a); invariant(b)
 - invariant(!(a || b)) -> invariant(!a); invariant(!b)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213977 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-25 21:45:17 +00:00
Hal Finkel
8ef7b17dfc Add @llvm.assume, lowering, and some basic properties
This is the first commit in a series that add an @llvm.assume intrinsic which
can be used to provide the optimizer with a condition it may assume to be true
(when the control flow would hit the intrinsic call). Some basic properties are added here:

 - llvm.invariant(true) is dead.
 - llvm.invariant(false) is unreachable (this directly corresponds to the
   documented behavior of MSVC's __assume(0)), so is llvm.invariant(undef).

The intrinsic is tagged as writing arbitrarily, in order to maintain control
dependencies. BasicAA has been updated, however, to return NoModRef for any
particular location-based query so that we don't unnecessarily block code
motion.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213973 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-25 21:13:35 +00:00
Duncan P. N. Exon Smith
2602b66b91 Move -verify-use-list-order into llvm-uselistorder
Ugh.  Turns out not even transformation passes link in how to read IR.
I sincerely believe the buildbots will finally agree with my system
after this though.  (I don't really understand why all of this has been
working on my system, but not on all the buildbots.)

Create a new tool called llvm-uselistorder to use for verifying use-list
order.  For now, just dump everything from the (now defunct)
-verify-use-list-order pass into the tool.

This might be a better way to test use-list order anyway.

Part of PR5680.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213957 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-25 17:13:03 +00:00
Hal Finkel
9f0a2a8bd5 Convert noalias parameter attributes into noalias metadata during inlining
This functionality is currently turned off by default.

Part of the motivation for introducing scoped-noalias metadata is to enable the
preservation of noalias parameter attribute information after inlining.
Sometimes this can be inferred from the code in the caller after inlining, but
often we simply lose valuable information.

The overall process if fairly simple:
 1. Create a new unqiue scope domain.
 2. For each (used) noalias parameter, create a new alias scope.
 3. For each pointer, collect the underlying objects. Add a noalias scope for
    each noalias parameter from which we're not derived (and has not been
    captured prior to that point).
 4. Add an alias.scope for each noalias parameter from which we might be
    derived (or has been captured before that point).

Note that the capture checks apply only if one of the underlying objects is not
an identified function-local object.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213949 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-25 15:50:08 +00:00
Duncan P. N. Exon Smith
deb8e30913 Try to fix a layering violation introduced by r213945
The dragonegg buildbot (and others?) started failing after
r213945/r213946 because `llvm-as` wasn't linking in the bitcode reader.
I think moving the verify functions to the same file as the verify pass
should fix the build.  Adding a command-line option for maintaining
use-list order in assembly as a drive-by to prevent warnings about
unused static functions.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213947 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-25 15:41:49 +00:00
Duncan P. N. Exon Smith
7bf73bd378 IPO: Add use-list-order verifier
Add a -verify-use-list-order pass, which shuffles use-list order, writes
to bitcode, reads back, and verifies that the (shuffled) order matches.

  - The utility functions live in lib/IR/UseListOrder.cpp.

  - Moved (and renamed) the command-line option to enable writing
    use-lists, so that this pass can return early if the use-list orders
    aren't being serialized.

It's not clear that this pass is the right direction long-term (perhaps
a separate tool instead?), but short-term it's a great way to test the
use-list order prototype.  I've added an XFAIL-ed testcase that I'm
hoping to get working pretty quickly.

This is part of PR5680.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213945 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-25 14:49:26 +00:00
Mark Heffernan
d10aa6f8b2 After unrolling a loop with llvm.loop.unroll.count metadata (unroll factor
hint) the loop unroller replaces the llvm.loop.unroll.count metadata with
llvm.loop.unroll.disable metadata to prevent any subsequent unrolling
passes from unrolling more than the hint indicates.  This patch fixes
an issue where loop unrolling could be disabled for other loops as well which
share the same llvm.loop metadata.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213900 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-24 22:36:40 +00:00
Manman Ren
0349d541d2 Feedback from Hans on r213815. No functionaility change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213895 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-24 21:13:20 +00:00
Hal Finkel
16fd27b2c3 Add scoped-noalias metadata
This commit adds scoped noalias metadata. The primary motivations for this
feature are:
  1. To preserve noalias function attribute information when inlining
  2. To provide the ability to model block-scope C99 restrict pointers

Neither of these two abilities are added here, only the necessary
infrastructure. In fact, there should be no change to existing functionality,
only the addition of new features. The logic that converts noalias function
parameters into this metadata during inlining will come in a follow-up commit.

What is added here is the ability to generally specify noalias memory-access
sets. Regarding the metadata, alias-analysis scopes are defined similar to TBAA
nodes:

!scope0 = metadata !{ metadata !"scope of foo()" }
!scope1 = metadata !{ metadata !"scope 1", metadata !scope0 }
!scope2 = metadata !{ metadata !"scope 2", metadata !scope0 }
!scope3 = metadata !{ metadata !"scope 2.1", metadata !scope2 }
!scope4 = metadata !{ metadata !"scope 2.2", metadata !scope2 }

Loads and stores can be tagged with an alias-analysis scope, and also, with a
noalias tag for a specific scope:

... = load %ptr1, !alias.scope !{ !scope1 }
... = load %ptr2, !alias.scope !{ !scope1, !scope2 }, !noalias !{ !scope1 }

When evaluating an aliasing query, if one of the instructions is associated
with an alias.scope id that is identical to the noalias scope associated with
the other instruction, or is a descendant (in the scope hierarchy) of the
noalias scope associated with the other instruction, then the two memory
accesses are assumed not to alias.

Note that is the first element of the scope metadata is a string, then it can
be combined accross functions and translation units. The string can be replaced
by a self-reference to create globally unqiue scope identifiers.

[Note: This overview is slightly stylized, since the metadata nodes really need
to just be numbers (!0 instead of !scope0), and the scope lists are also global
unnamed metadata.]

Existing noalias metadata in a callee is "cloned" for use by the inlined code.
This is necessary because the aliasing scopes are unique to each call site
(because of possible control dependencies on the aliasing properties). For
example, consider a function: foo(noalias a, noalias b) { *a = *b; } that gets
inlined into bar() { ... if (...) foo(a1, b1); ... if (...) foo(a2, b2); } --
now just because we know that a1 does not alias with b1 at the first call site,
and a2 does not alias with b2 at the second call site, we cannot let inlining
these functons have the metadata imply that a1 does not alias with b2.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213864 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-24 14:25:39 +00:00
Aaron Ballman
e8d5c379ac Fixing an MSVC conversion warning about implicitly converting the shift results to 64-bits. No functional change intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213863 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-24 14:24:59 +00:00
Hal Finkel
2c7c54c86c AA metadata refactoring (introduce AAMDNodes)
In order to enable the preservation of noalias function parameter information
after inlining, and the representation of block-level __restrict__ pointer
information (etc.), additional kinds of aliasing metadata will be introduced.
This metadata needs to be carried around in AliasAnalysis::Location objects
(and MMOs at the SDAG level), and so we need to generalize the current scheme
(which is hard-coded to just one TBAA MDNode*).

This commit introduces only the necessary refactoring to allow for the
introduction of other aliasing metadata types, but does not actually introduce
any (that will come in a follow-up commit). What it does introduce is a new
AAMDNodes structure to hold all of the aliasing metadata nodes associated with
a particular memory-accessing instruction, and uses that structure instead of
the raw MDNode* in AliasAnalysis::Location, etc.

No functionality change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213859 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-24 12:16:19 +00:00
Manman Ren
4cae9cb034 SimplifyCFG: fix a bug in switch to table conversion
We use gep to access the global array "switch.table", and the table index
should be treated as unsigned. When the highest bit is 1, this commit
zero-extends the index to an integer type with larger size.

For a switch on i2, we used to generate:
%switch.tableidx = sub i2 %0, -2
getelementptr inbounds [4 x i64]* @switch.table, i32 0, i2 %switch.tableidx

It is incorrect when %switch.tableidx is 2 or 3. The fix is to generate
%switch.tableidx = sub i2 %0, -2
%switch.tableidx.zext = zext i2 %switch.tableidx to i3
getelementptr inbounds [4 x i64]* @switch.table, i32 0, i3 %switch.tableidx.zext

rdar://17735071


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213815 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-23 23:13:23 +00:00
David Blaikie
ccd1035ad4 ArgPromo+DebugInfo: Handle updating debug info over multiple applications of argument promotion.
While the subprogram map cache used by Dead Argument Elimination works
there, I made a mistake when reusing it for Argument Promotion in
r212128 because ArgPromo may transform functions more than once whereas
DAE transforms each function only once, removing all the dead arguments
in one go.

To address this, ensure that the map is updated after each argument
promotion.

In retrospect it might be a little wasteful to create a map of all
subprograms when only handling a single CGSCC, but the alternative is
walking the debug info for each function in the CGSCC that gets updated.
It's not clear to me what the right tradeoff is there, but since the
current tradeoff seems to be working OK (and the code to keep things
updated is very cheap), let's stick with that for now.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213805 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-23 22:09:29 +00:00
Mark Heffernan
d55c7c7f42 Do not add unroll disable metadata after unrolling pass for loops with #pragma clang loop unroll(full).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213789 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-23 20:05:44 +00:00
Mark Heffernan
e8d7ebcd5a In unroll pragma syntax and loop hint metadata, change "enable" forms to a new form using the string "full".
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213772 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-23 17:31:37 +00:00
Nick Lewycky
1bda2d9386 We may visit a call that uses an alloca multiple times in callUsesLocalStack, sometimes with IsNocapture true and sometimes with IsNocapture false. We accidentally skipped work we needed to do in the IsNocapture=false case if we were called with IsNocapture=true the first time. Fixes PR20405!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213726 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-23 06:24:49 +00:00
Suyog Sarda
c9ea25fc51 This patch implements optimization as mentioned in PR19753: Optimize comparisons with "ashr/lshr exact" of a constanst.
It handles the errors which were seen in PR19958 where wrong code was being emitted due to earlier patch.
Added code for lshr as well as non-exact right shifts.

It implements : 
(icmp eq/ne (ashr/lshr const2, A), const1)" ->
(icmp eq/ne A, Log2(const2/const1)) ->
(icmp eq/ne A, Log2(const2) - Log2(const1))

Differential Revision: http://reviews.llvm.org/D4068
 


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213678 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-22 19:19:36 +00:00
Suyog Sarda
3326ee444a Added InstCombine transform for pattern "(A & B) ^ (A ^ B) -> (A | B)"
Patch idea by Ankit Jain !

Differential Revision: http://reviews.llvm.org/D4618



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213677 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-22 18:30:54 +00:00
Suyog Sarda
1a1b1f708d Added InstCombine Transform for patterns:
"((~A & B) | A) -> (A | B)" and "((A & B) | ~A) -> (~A | B)"

Original Patch credit to Ankit Jain !!

Differential Revision: http://reviews.llvm.org/D4591



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213676 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-22 18:09:41 +00:00
Alexey Samsonov
f969d5b86b [ASan] Fix comments about __sanitizer_cov function
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213673 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-22 17:46:09 +00:00
Suyog Sarda
578c74e35d This patch implements transform for pattern "(A | B) ^ (~A) -> (A | ~B)".
Patch Credit to Ankit Jain !!

Differential Revision: http://reviews.llvm.org/D4588



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213662 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-22 15:37:39 +00:00
Sanjay Patel
8e80aa5d5f fixed typo in comment
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213614 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-22 04:57:06 +00:00
Mark Heffernan
bc7f1aba2d Rename metadata llvm.loop.vectorize.unroll to llvm.loop.vectorize.interleave.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213588 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 23:11:03 +00:00
Duncan P. N. Exon Smith
facdfc6781 Revert "[C++11] Add predecessors(BasicBlock *) / successors(BasicBlock *) iterator ranges."
This reverts commit r213474 (and r213475), which causes a miscompile on
a stage2 LTO build.  I'll reply on the list in a moment.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213562 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 17:06:51 +00:00
Gerolf Hoflehner
10437f66fa Fix for regression: [Bug 20369] wrong code at -O3 on x86_64-linux-gnu in 64-bit mode
Prevents hoisting of loads above stores and sinking of stores below loads
in MergedLoadStoreMotion.cpp (rdar://15991737)



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213497 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-21 03:02:46 +00:00
Hal Finkel
07d4e558b3 [LoopVectorize] Remove an unused private AA pointer
Thanks to the lld-x86_64-darwin13 builder for catching this first.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213488 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-20 23:28:25 +00:00
Hal Finkel
160f9b9c10 [LoopVectorize] Use AA to partition potential dependency checks
Prior to this change, the loop vectorizer did not make use of the alias
analysis infrastructure. Instead, it performed memory dependence analysis using
ScalarEvolution-based linear dependence checks within equivalence classes
derived from the results of ValueTracking's GetUnderlyingObjects.

Unfortunately, this meant that:
  1. The loop vectorizer had logic that essentially duplicated that in BasicAA
     for aliasing based on identified objects.
  2. The loop vectorizer could not partition the space of dependency checks
     based on information only easily available from within AA (TBAA metadata is
     currently the prime example).

This means, for example, regardless of whether -fno-strict-aliasing was
provided, the vectorizer would only vectorize this loop with a runtime
memory-overlap check:

void foo(int *a, float *b) {
  for (int i = 0; i < 1600; ++i)
    a[i] = b[i];
}

This is suboptimal because the TBAA metadata already provides the information
necessary to show that this check unnecessary. Of course, the vectorizer has a
limit on the number of such checks it will insert, so in practice, ignoring
TBAA means not vectorizing more-complicated loops that we should.

This change causes the vectorizer to use an AliasSetTracker to keep track of
the pointers in the loop. The resulting alias sets are then used to partition
the space of dependency checks, and potential runtime checks; this results in
more-efficient vectorizations.

When pointer locations are added to the AliasSetTracker, two things are done:
  1. The location size is set to UnknownSize (otherwise you'd not catch
     inter-iteration dependencies)
  2. For instructions in blocks that would need to be predicated, TBAA is
     removed (because the metadata might have a control dependency on the condition
     being speculated).

For non-predicated blocks, you can leave the TBAA metadata. This is safe
because you can't have an iteration dependency on the TBAA metadata (if you
did, and you unrolled sufficiently, you'd end up with the same pointer value
used by two accesses that TBAA says should not alias, and that would yield
undefined behavior).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213486 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-20 23:07:52 +00:00
Manuel Jacob
a4697dad19 [C++11] Add predecessors(BasicBlock *) / successors(BasicBlock *) iterator ranges.
Summary: This patch introduces two new iterator ranges and updates existing code to use it.  No functional change intended.

Test Plan: All tests (make check-all) still pass.

Reviewers: dblaikie

Reviewed By: dblaikie

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D4481

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213474 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-20 09:10:11 +00:00
Matt Arsenault
5e1c96a632 Templatify RegionInfo so it works on MachineBasicBlocks
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213456 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-19 18:29:29 +00:00
Hal Finkel
4df656952a [LoopVectorize] Use CreateAligned(Load|Store)
IRBuilder has CreateAligned(Load|Store) functions; use them and we don't need
to make a second call to setAlignment.

No functionality change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213453 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-19 13:39:45 +00:00