Commit Graph

4866 Commits

Author SHA1 Message Date
Tom Stellard
7dfcb84fc1 Fix for a regression caused by the LoopVectorizer when
vectorizing loops with memory accesses to non-zero address spaces. It
simply dropped the AS info. Fixes PR16306.


Merged from r184103
Author: Pekka Jaaskelainen <pekka.jaaskelainen@tut.fi>
Date:   Mon Jun 17 18:49:06 2013 +0000

git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_33@185869 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-08 21:20:34 +00:00
Bill Wendling
1419ad7b43 Merging r183035:
------------------------------------------------------------------------
r183035 | arnolds | 2013-05-31 12:53:50 -0700 (Fri, 31 May 2013) | 7 lines

LoopVectorize: PHIs with only outside users should prevent vectorization

We check that instructions in the loop don't have outside users (except if
they are reduction values). Unfortunately, we skipped this check for
if-convertable PHIs.

Fixes PR16184.
------------------------------------------------------------------------


git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_33@183189 91177308-0d34-0410-b5e6-96231b3b80d8
2013-06-04 04:35:28 +00:00
Andrew Trick
6f2ae41d21 Merge 183060: Prevent loop-unroll from making assumptions about undefined behavior.
Fixes rdar:14036816, PR16130.

    There is an opportunity to compute precise trip counts for 'or'
    expressions and multi-exit loops.
    rdar:14038809: Optimize trip count computation for multi-exit loops.

    To do this we need to record the fact that ExitLimit assumes NSW. When
    it does not we can safely assume that the loop trip count is the
    minimum ExitLimt across all subexpressions and loop exits.

    git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@183060 91177308-0d34-0410-b5e6-96231b3b80d8


git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_33@183066 91177308-0d34-0410-b5e6-96231b3b80d8
2013-06-01 01:37:44 +00:00
Bill Wendling
da897215b2 Merging r182656:
------------------------------------------------------------------------
r182656 | d0k | 2013-05-24 11:05:35 -0700 (Fri, 24 May 2013) | 3 lines

LoopVectorize: LoopSimplify can't canonicalize loops with an indirectbr in it, don't assert on those cases.

Fixes PR16139.
------------------------------------------------------------------------


git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_33@182785 91177308-0d34-0410-b5e6-96231b3b80d8
2013-05-28 18:37:09 +00:00
Bill Wendling
1df0680640 Merging r182485:
------------------------------------------------------------------------
r182485 | arnolds | 2013-05-22 09:54:56 -0700 (Wed, 22 May 2013) | 7 lines

LoopVectorize: Make Value pointers that could be RAUW'ed a VH

The Value pointers we store in the induction variable list can be RAUW'ed by a
call to SCEVExpander::expandCodeFor, use a TrackingVH instead. Do the same thing
in some other places where we store pointers that could potentially be RAUW'ed.

Fixes PR16073.
------------------------------------------------------------------------


git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_33@182492 91177308-0d34-0410-b5e6-96231b3b80d8
2013-05-22 17:30:06 +00:00
Bill Wendling
5b85a9b5ad Merging r181524:
------------------------------------------------------------------------
r181524 | rafael | 2013-05-09 10:22:59 -0700 (Thu, 09 May 2013) | 4 lines

Don't replace an alias in llvm.used with its target.

When we replace an internal alias with its target, be careful not to
replace the entry in llvm.used (and llvm.compiler_used).
------------------------------------------------------------------------


git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_33@181909 91177308-0d34-0410-b5e6-96231b3b80d8
2013-05-15 18:16:42 +00:00
Bill Wendling
06362e2450 Merging r181586:
------------------------------------------------------------------------
r181586 | d0k | 2013-05-10 02:16:52 -0700 (Fri, 10 May 2013) | 3 lines

InstCombine: Verify the type before transforming uitofp into select.

PR15952.
------------------------------------------------------------------------


git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_33@181813 91177308-0d34-0410-b5e6-96231b3b80d8
2013-05-14 18:30:01 +00:00
Bill Wendling
c7594e48ed Merging r181286:
------------------------------------------------------------------------
r181286 | arnolds | 2013-05-06 21:37:05 -0700 (Mon, 06 May 2013) | 7 lines

LoopVectorize: getConsecutiveVector must respect signed arithmetic

We were passing an i32 to ConstantInt::get where an i64 was needed and we must
also pass the sign if we pass negatives numbers. The start index passed to
getConsecutiveVector must also be signed.

Should fix PR15882.
------------------------------------------------------------------------


git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_33@181455 91177308-0d34-0410-b5e6-96231b3b80d8
2013-05-08 18:13:06 +00:00
David Majnemer
8ec23cb07e InstCombine: (X ^ signbit) + C -> X + (signbit ^ C)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181249 91177308-0d34-0410-b5e6-96231b3b80d8
2013-05-06 21:21:31 +00:00
Jean-Luc Duprat
0aa2b8800c Test results verified using FileCheck rather than grep | count
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181234 91177308-0d34-0410-b5e6-96231b3b80d8
2013-05-06 18:45:16 +00:00
Andrew Trick
fcf79528da Rotate multi-exit loops even if the latch was simplified.
Test case by Michele Scandale!

Fixes PR10293: Load not hoisted out of loop with multiple exits.

There are few regressions with this patch, now tracked by
rdar:13817079, and a roughly equal number of improvements. The
regressions are almost certainly back luck because LoopRotate has very
little idea of whether rotation is profitable. Doing better requires a
more comprehensive solution.

This checkin is a quick fix that lacks generality (PR10293 has
a counter-example). But it trivially fixes the case in PR10293 without
interfering with other cases, and it does satify the criteria that
LoopRotate is a loop canonicalization pass that should avoid
heuristics and special cases.

I can think of two approaches that would probably be better in
the long run. Ultimately they may both make sense.

(1) LoopRotate should check that the current header would make a good
loop guard, and that the loop does not already has a sufficient
guard. The artifical SimplifiedLoopLatch check would be unnecessary,
and the design would be more general and canonical. Two difficulties:

- We need a strong guarantee that we won't endlessly rotate, so the
  analysis would need to be precise in order to avoid the
  SimplifiedLoopLatch precondition.

- Analysis like this are usually based on SCEV, which we don't want to
  rely on.

(2) Rotate on-demand in late loop passes. This could even be done by
shoving the loop back on the queue after the optimization that needs
it. This could work well when we find LICM opportunities in
multi-branch loops. This requires some work, and it doesn't really
solve the problem of SCEV wanting a loop guard before the analysis.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181230 91177308-0d34-0410-b5e6-96231b3b80d8
2013-05-06 17:58:18 +00:00
Jean-Luc Duprat
81fa2abc85 Fix add4.ll test cmdline so that it passes
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181219 91177308-0d34-0410-b5e6-96231b3b80d8
2013-05-06 17:18:47 +00:00
Jean-Luc Duprat
c5cf6e5365 Provide InstCombines for the following 3 cases:
A * (1 - (uitofp i1 C)) -> select C, 0, A
B * (uitofp i1 C) -> select C, B, 0
select C, 0, A + select C, B, 0 -> select C, B, A

These come up in code that has been hand-optimized from a select to a linear blend, 
on platforms where that may have mattered. We want to undo such changes 
with the following transform:
A*(1 - uitofp i1 C) + B*(uitofp i1 C) -> select C, A, B



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181216 91177308-0d34-0410-b5e6-96231b3b80d8
2013-05-06 16:55:50 +00:00
Nadav Rotem
4ee312bac1 Revert r164763 because it introduces new shuffles.
Thanks Nick Lewycky for pointing this out.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181177 91177308-0d34-0410-b5e6-96231b3b80d8
2013-05-06 02:39:09 +00:00
Matt Arsenault
8b9dc21d6f Fix unchecked uses of DominatorTree in MemoryDependenceAnalysis.
Use unknown results for places where it would be needed

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181176 91177308-0d34-0410-b5e6-96231b3b80d8
2013-05-06 02:07:24 +00:00
Rafael Espindola
eaf14786ca Fix const merging when an alias of a const is llvm.used.
We used to disable constant merging not only if a constant is llvm.used, but
also if an alias of a constant is llvm.used. This change fixes that.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181175 91177308-0d34-0410-b5e6-96231b3b80d8
2013-05-06 01:48:55 +00:00
Arnold Schwaighofer
87defd0924 LoopVectorize: Add support for floating point min/max reductions
Add support for min/max reductions when "no-nans-float-math" is enabled. This
allows us to assume we have ordered floating point math and treat ordered and
unordered predicates equally.

radar://13723044

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181144 91177308-0d34-0410-b5e6-96231b3b80d8
2013-05-05 01:54:48 +00:00
Arnold Schwaighofer
c1738fdadd LoopVectorize: We don't need an identity element for min/max reductions
We can just use the initial element that feeds the reduction.

  max(max(x, y), z) == max(max(x,y), max(x,z))

radar://13723044

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181141 91177308-0d34-0410-b5e6-96231b3b80d8
2013-05-05 01:54:42 +00:00
Nadav Rotem
4bcd5f888f LoopVectorizer: Add support for if-conversion of PHINodes with 3+ incoming values.
By supporting the vectorization of PHINodes with more than two incoming values we can increase the complexity of nested if statements.

We can now vectorize this loop:

int foo(int *A, int *B, int n) {
  for (int i=0; i < n; i++) {
    int x = 9;
    if (A[i] > B[i]) {
      if (A[i] > 19) {
        x = 3;
      } else if (B[i] < 4 ) {
        x = 4;
      } else {
        x = 5;
      }
    }
    A[i] = x;
  }
}



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181037 91177308-0d34-0410-b5e6-96231b3b80d8
2013-05-03 17:42:55 +00:00
Manman Ren
436849be6a TBAA: remove !tbaa from testing cases if not used.
This will make it easier to turn on struct-path aware TBAA since the metadata
format will change.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180935 91177308-0d34-0410-b5e6-96231b3b80d8
2013-05-02 18:11:35 +00:00
David Majnemer
304099a56d Add a test for the foldSelectICmpAndOr fix committed in r180779.
This tests a case where C1 and C2 were the same but X and Y were different
widths.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180907 91177308-0d34-0410-b5e6-96231b3b80d8
2013-05-02 02:44:23 +00:00
Nadav Rotem
fee6969463 SROA: Generate selects instead of shuffles when blending values because this is the cannonical form.
Shuffles are more difficult to lower and we usually don't touch them, while we do optimize selects more often.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180875 91177308-0d34-0410-b5e6-96231b3b80d8
2013-05-01 19:53:30 +00:00
Jim Grosbach
10cc563bfe Revert "InstCombine: Fold more shuffles of shuffles."
This reverts commit r180802

There's ongoing discussion about whether this is the right place to make
this transformation. Reverting for now while we figure it out.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180834 91177308-0d34-0410-b5e6-96231b3b80d8
2013-05-01 00:25:27 +00:00
Jim Grosbach
6548096a2e InstCombine: Fold more shuffles of shuffles.
Always fold a shuffle-of-shuffle into a single shuffle when there's only one
input vector in the first place. Continue to be more conservative when there's
multiple inputs.

rdar://13402653
PR15866

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180802 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-30 20:43:52 +00:00
Manman Ren
2dc50d3067 TBAA: remove !tbaa from testing cases if not used.
This will make it easier to turn on struct-path aware TBAA since the metadata
format will change.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180796 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-30 17:52:57 +00:00
David Majnemer
defce4cfd6 Fix "Combine bit test + conditional or into simple math"
This fixes the optimization introduced in r179748 and reverted in r179750.

While the optimization was sound, it did not properly respect differences in
bit-width.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180777 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-30 08:57:58 +00:00
Arnold Schwaighofer
8228ffe72d SimplifyCFG: If convert single conditional stores
This resurrects r179957, but adds code that makes sure we don't touch
atomic/volatile stores:

This transformation will transform a conditional store with a preceeding
uncondtional store to the same location:

 a[i] =
 may-alias with a[i] load
 if (cond)
   a[i] = Y

into an unconditional store.

 a[i] = X
 may-alias with a[i] load
 tmp = cond ? Y : X;
 a[i] = tmp

We assume that on average the cost of a mispredicted branch is going to be
higher than the cost of a second store to the same location, and that the
secondary benefits of creating a bigger basic block for other optimizations to
work on outway the potential case where the branch would be correctly predicted
and the cost of the executing the second store would be noticably reflected in
performance.

hmmer's execution time improves by 30% on an imac12,2 on ref data sets. With
this change we are on par with gcc's performance (gcc also performs this
transformation). There was a 1.2 % performance improvement on a ARM swift chip.
Other tests in the test-suite+external seem to be mostly uninfluenced in my
experiments:
This optimization was triggered on 41 tests such that the executable was
different before/after the patch. Only 1 out of the 40 tests (dealII) was
reproducable below 100% (by about .4%). Given that hmmer benefits so much I
believe this to be a fair trade off.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180731 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-29 21:28:24 +00:00
Michael Gottesman
f11a6856cc [objc-arc] Apply the RV optimization to retains next to calls in ObjCARCContract instead of ObjCARCOpts.
Turning retains into retainRV calls disrupts the data flow analysis in
ObjCARCOpts. Thus we move it as late as we can by moving it into
ObjCARCContract.

We leave in the conversion from retainRV -> retain in ObjCARCOpt since
it enables the dataflow analysis.

rdar://10813093

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180698 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-29 06:53:53 +00:00
Shuxin Yang
4d4c54d29f Fix a XOR reassociation bug.
When Reassociator optimize "(x | C1)" ^ "(X & C2)", it may swap the two
subexpressions, however, it forgot to swap cached constants (of C1 and C2)
accordingly.

rdar://13739160


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180676 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-27 18:02:12 +00:00
Michael Gottesman
2c2e85536d [objc-arc] Test cleanups.
Mainly adding paranoid checks for the closing brace of a function to
help with FileCheck error readability. Also some other minor changes.

No actual CHECK changes.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180668 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-27 05:25:54 +00:00
Nadav Rotem
7557e521e5 LoopVectorizer: Calculate the number of pointers to disambiguate at runtime based on the numbers of reads and writes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180593 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-26 05:08:59 +00:00
Nadav Rotem
975b1ddf60 LoopVectorizer: No need to generate pointer disambiguation checks between readonly pointers.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180570 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-25 19:55:03 +00:00
Arnold Schwaighofer
a4b8b4ccc9 LoopVectorize: Scalarize padded types
This patch disables memory-instruction vectorization for types that need padding
bytes, e.g., x86_fp80 has 10 bytes store size with 6 bytes padding in darwin on
x86_64. Because the load/store vectorization is performed by the bit casting to
a packed vector, which has incompatible memory layout due to the lack of padding
bytes, the present vectorizer produces inconsistent result for memory
instructions of those types.
This patch checks an equality of the AllocSize of a scalar type and allocated
size for each vector element, to ensure that there is no padding bytes and the
array can be read/written using vector operations.

Patch by Daisuke Takahashi!

Fixes PR15758.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180196 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-24 16:16:01 +00:00
Arnold Schwaighofer
b03ad17536 LoopVectorizer: Bail out if we don't have datalayout we need it
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180195 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-24 16:15:58 +00:00
Nadav Rotem
a7d9a6ee63 LoopVectorizer: Fix 15830. When scalarizing and unrolling stores make sure that the order in which the elements are scalarized is the same as the original order.
This fixes a miscompilation in FreeBSD's regex library.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180121 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-23 17:12:42 +00:00
Pekka Jaaskelainen
2e59a125fc Call the potentially costly isAnnotatedParallel() only once.
Made the uniform write test's checks a bit stricter.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180119 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-23 16:44:43 +00:00
Pekka Jaaskelainen
a8958769ea Refuse to (even try to) vectorize loops which have uniform writes,
even if erroneously annotated with the parallel loop metadata.

Fixes Bug 15794: 
"Loop Vectorizer: Crashes with the use of llvm.loop.parallel metadata"



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180081 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-23 08:08:51 +00:00
Anat Shemer
c9090b0723 Changed back (relative to commit 179786) the operations executed when extract(cast) is transformed to cast(extract). It uses the Builder class as before. In addition the result node is added to the Worklist, so all the previous extract users will become the new scalar cast users.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180045 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-22 20:51:10 +00:00
David Blaikie
c462db6d66 Revert "Revert "PR14606: debug info imported_module support""
This reverts commit r179840 with a fix to test/DebugInfo/two-cus-from-same-file.ll

I'm not sure why that test only failed on ARM & MIPS and not X86 Linux, even
though the debug info was clearly invalid on all of them, but this ought to fix
it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179996 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-22 06:12:31 +00:00
Benjamin Kramer
d81a0dee5b SROA: Don't crash on a select with two identical operands.
This is an edge case that can happen if we modify a chain of multiple selects.
Update all operands in that case and remove the assert. PR15805.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179982 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-21 17:48:39 +00:00
Arnold Schwaighofer
54d9a3e2df Revert "SimplifyCFG: If convert single conditional stores"
There is the temptation to make this tranform dependent on target information as
it is not going to be beneficial on all (sub)targets. Therefore, we should
probably do this in MI Early-Ifconversion.

This reverts commit r179957. Original commit message:

"SimplifyCFG: If convert single conditional stores

This transformation will transform a conditional store with a preceeding
uncondtional store to the same location:

a[i] =
may-alias with a[i] load
if (cond)
    a[i] = Y
into an unconditional store.

a[i] = X
may-alias with a[i] load
tmp = cond ? Y : X;
a[i] = tmp

We assume that on average the cost of a mispredicted branch is going to be
higher than the cost of a second store to the same location, and that the
secondary benefits of creating a bigger basic block for other optimizations to
work on outway the potential case were the branch would be correctly predicted
and the cost of the executing the second store would be noticably reflected in
performance.

hmmer's execution time improves by 30% on an imac12,2 on ref data sets. With
this change we are on par with gcc's performance (gcc also performs this
transformation). There was a 1.2 % performance improvement on a ARM swift chip.
Other tests in the test-suite+external seem to be mostly uninfluenced in my
experiments:
This optimization was triggered on 41 tests such that the executable was
different before/after the patch. Only 1 out of the 40 tests (dealII) was
reproducable below 100% (by about .4%). Given that hmmer benefits so much I
believe this to be a fair trade off.

I am going to watch performance numbers across the builtbots and will revert
this if anything unexpected comes up."

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179980 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-21 13:09:04 +00:00
Nadav Rotem
b86dff862f SLPVectorize: Add support for vectorization of casts.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179975 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-21 08:05:59 +00:00
Michael Gottesman
899b2f9d0b [objc-arc] Cleaned up tail-call-invariant-enforcement.ll.
Specifically:

1. Added checks that unwind is being properly added to various instructions.
2. Fixed the declaration/calling of objc_release to have a return type of void.
3. Moved all checks to precede the functions and added checks to ensure that the
checks would only match inside the specific function that we are attempting to
check.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179973 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-21 02:59:44 +00:00
Michael Gottesman
bf9cac7ebb [objc-arc] Check that objc-arc-expand properly handles all strictly forwarding calls and does not touch calls which are not strictly forwarding (i.e. objc_retainBlock).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179972 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-21 01:57:46 +00:00
Michael Gottesman
755aabc04e [objc-arc] Renamed the test file clang-arc-used-intrinsic-removed-if-isolated.ll -> intrinsic-use-isolated.ll to match the other test file intrinsic-use.ll.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179971 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-21 01:42:24 +00:00
Nadav Rotem
4f38e16b89 Fix PR15800. Do not try to vectorize vectors and structs.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179960 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-20 22:29:43 +00:00
Arnold Schwaighofer
f7af1987dd SimplifyCFG: If convert single conditional stores
This transformation will transform a conditional store with a preceeding
uncondtional store to the same location:

 a[i] =
 may-alias with a[i] load
 if (cond)
   a[i] = Y

into an unconditional store.

 a[i] = X
 may-alias with a[i] load
 tmp = cond ? Y : X;
 a[i] = tmp

We assume that on average the cost of a mispredicted branch is going to be
higher than the cost of a second store to the same location, and that the
secondary benefits of creating a bigger basic block for other optimizations to
work on outway the potential case were the branch would be correctly predicted
and the cost of the executing the second store would be noticably reflected in
performance.

hmmer's execution time improves by 30% on an imac12,2 on ref data sets. With
this change we are on par with gcc's performance (gcc also performs this
transformation). There was a 1.2 % performance improvement on a ARM swift chip.
Other tests in the test-suite+external seem to be mostly uninfluenced in my
experiments:
This optimization was triggered on 41 tests such that the executable was
different before/after the patch. Only 1 out of the 40 tests (dealII) was
reproducable below 100% (by about .4%). Given that hmmer benefits so much I
believe this to be a fair trade off.

I am going to watch performance numbers across the builtbots and will revert
this if anything unexpected comes up.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179957 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-20 21:42:09 +00:00
Nuno Lopes
bf9fba961b recommit tests
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179955 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-20 17:39:52 +00:00
Nadav Rotem
1d2ad834f2 SLPVectorizer: Improve the cost model for loop invariant broadcast values.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179930 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-20 06:13:47 +00:00
Benjamin Kramer
24a5f30f77 MergeFunc: Make pointer and integer types generate the same hash.
The logic that actually compares the types considers pointers and integers the
same if they are of the same size. This created a strange mismatch between hash
and reality and made the test case for this fail on some platforms (yay,
test cases).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179905 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-19 23:06:44 +00:00