Commit Graph

154 Commits

Author SHA1 Message Date
Andrew Trick
ecb35ece5c SCEV fix. In general, Add/Mul expressions should not inherit NSW/NUW.
This reverts r139450, fixes r139453, and adds much needed comments and a
unit test.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@145367 91177308-0d34-0410-b5e6-96231b3b80d8
2011-11-29 02:16:38 +00:00
Andrew Trick
d2b5e2dd44 Filecheckize.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@145363 91177308-0d34-0410-b5e6-96231b3b80d8
2011-11-29 02:05:23 +00:00
Nick Lewycky
89d093d5b6 Don't forget to check FlagNW when determining whether an AddRecExpr will wrap
or not. Patch by Brendon Cahoon!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@144173 91177308-0d34-0410-b5e6-96231b3b80d8
2011-11-09 07:11:37 +00:00
Benjamin Kramer
588d84c4df 2>&1 doesn't work here, it just creates an empty file called "&1"
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@143117 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-27 18:27:45 +00:00
Duncan Sands
f8a9eb1fa6 Restore commits 142790 and 142843 - they weren't breaking the build
bots.  Original commit messages:
- Reapply r142781 with fix. Original message:

  Enhance SCEV's brute force loop analysis to handle multiple PHI nodes in the
  loop header when computing the trip count.

  With this, we now constant evaluate:
    struct ListNode { const struct ListNode *next; int i; };
    static const struct ListNode node1 = {0, 1};
    static const struct ListNode node2 = {&node1, 2};
    static const struct ListNode node3 = {&node2, 3};
    int test() {
      int sum = 0;
      for (const struct ListNode *n = &node3; n != 0; n = n->next)
        sum += n->i;
      return sum;
    }

- Now that we look at all the header PHIs, we need to consider all the header PHIs
  when deciding that the loop has stopped evolving. Fixes miscompile in the gcc
  torture testsuite!



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@142919 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-25 12:28:52 +00:00
Duncan Sands
526c80bae4 Speculatively revert commits 142790 and 142843 to see if it fixes
the dragonegg and llvm-gcc self-host buildbots.  Original commit
messages:
- Reapply r142781 with fix. Original message:

  Enhance SCEV's brute force loop analysis to handle multiple PHI nodes in the
  loop header when computing the trip count.

  With this, we now constant evaluate:
    struct ListNode { const struct ListNode *next; int i; };
    static const struct ListNode node1 = {0, 1};
    static const struct ListNode node2 = {&node1, 2};
    static const struct ListNode node3 = {&node2, 3};
    int test() {
      int sum = 0;
      for (const struct ListNode *n = &node3; n != 0; n = n->next)
        sum += n->i;
      return sum;
    }

- Now that we look at all the header PHIs, we need to consider all the header PHIs
when deciding that the loop has stopped evolving. Fixes miscompile in the gcc
torture testsuite!



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@142916 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-25 09:26:43 +00:00
Nick Lewycky
3846163aee Now that we look at all the header PHIs, we need to consider all the header PHIs
when deciding that the loop has stopped evolving. Fixes miscompile in the gcc
torture testsuite!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@142843 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-24 21:02:38 +00:00
Nick Lewycky
7c3fc57472 Reapply r142781 with fix. Original message:
Enhance SCEV's brute force loop analysis to handle multiple PHI nodes in the
  loop header when computing the trip count.

  With this, we now constant evaluate:
    struct ListNode { const struct ListNode *next; int i; };
    static const struct ListNode node1 = {0, 1};
    static const struct ListNode node2 = {&node1, 2};
    static const struct ListNode node3 = {&node2, 3};
    int test() {
      int sum = 0;
      for (const struct ListNode *n = &node3; n != 0; n = n->next)
        sum += n->i;
      return sum;
    }


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@142790 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-24 06:57:05 +00:00
Nick Lewycky
38af3d5a8d Speculatively revert r142781. Bots are showing
Assertion `i_nocapture < OperandTraits<PHINode>::operands(this) && "getOperand() out of range!"' failed.
coming out of indvars.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@142786 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-24 04:00:25 +00:00
Nick Lewycky
795cb48f1a Enhance SCEV's brute force loop analysis to handle multiple PHI nodes in the
loop header when computing the trip count.

With this, we now constant evaluate:
  struct ListNode { const struct ListNode *next; int i; };
  static const struct ListNode node1 = {0, 1};
  static const struct ListNode node2 = {&node1, 2};
  static const struct ListNode node3 = {&node2, 3};
  int test() {
    int sum = 0;
    for (const struct ListNode *n = &node3; n != 0; n = n->next)
      sum += n->i;
    return sum;
  }


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@142781 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-23 23:43:14 +00:00
Nick Lewycky
614fef6d5a Make SCEV's brute force analysis stronger in two ways. Firstly, we should be
able to constant fold load instructions where the argument is a constant.
Second, we should be able to watch multiple PHI nodes through the loop; this
patch only supports PHIs in loop headers, more can be done here.

With this patch, we now constant evaluate:
  static const int arr[] = {1, 2, 3, 4, 5};
  int test() {
    int sum = 0;
    for (int i = 0; i < 5; ++i) sum += arr[i];
    return sum;
  }


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@142731 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-22 19:58:20 +00:00
Andrew Trick
0c388583fb Missing test case for r141164.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@141166 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-05 06:23:32 +00:00
Nick Lewycky
1cbae18cf6 Reapply r140979 with fix! We never did get a testcase, but careful review of the
logic by David Meyer revealed this bug.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@140992 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-03 07:10:45 +00:00
Nick Lewycky
4fcc80a486 Revert r140979 due to reports of bootstrap failure.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@140980 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-03 05:14:59 +00:00
Nick Lewycky
8fde4f5842 Add one more case we compute a max trip count.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@140979 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-03 01:03:57 +00:00
Andrew Trick
2e95d76f8c This test only makes sense with -enable-iv-rewrite.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139576 91177308-0d34-0410-b5e6-96231b3b80d8
2011-09-13 02:45:26 +00:00
Nick Lewycky
c103a08a11 This transform only handles two-operand AddRec's. Prevent it from trying to
handle anything more complex. Fixes PR10383 again!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139186 91177308-0d34-0410-b5e6-96231b3b80d8
2011-09-06 21:42:18 +00:00
Nick Lewycky
fa151a79ed The logic inside getMulExpr to simplify {a,+,b}*{c,+,d} was wrong, which was
visible given a=b=c=d=1, on iteration #1 (the second iteration). Replace it with
correct math. Fixes PR10383!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139133 91177308-0d34-0410-b5e6-96231b3b80d8
2011-09-06 05:05:14 +00:00
Nick Lewycky
b2840fdcd8 Revert r139126 due to selfhost failures reported by buildbots.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139130 91177308-0d34-0410-b5e6-96231b3b80d8
2011-09-06 02:43:13 +00:00
Nick Lewycky
77b7352db0 Teach SCEV to report a max backedge count in one interesting case in
HowFarToZero; the case for a canonical loop.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139126 91177308-0d34-0410-b5e6-96231b3b80d8
2011-09-05 23:25:16 +00:00
Chris Lattner
a53616d08b Remove support for parsing the "type i32" syntax for defining a numbered
top level type without a specified number.  This syntax isn't documented
and blocks forward progress.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@133371 91177308-0d34-0410-b5e6-96231b3b80d8
2011-06-19 00:03:46 +00:00
Chris Lattner
b85e4eba85 rip out a ton of intrinsic modernization logic from AutoUpgrade.cpp, which is
for pre-2.9 bitcode files.  We keep x86 unaligned loads, movnt, crc32, and the
target indep prefetch change.

As usual, updating the testsuite is a PITA.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@133337 91177308-0d34-0410-b5e6-96231b3b80d8
2011-06-18 06:05:24 +00:00
Chris Lattner
7a1b9bdd2b Remove support for using "foo" as symbols instead of %"foo". This is ancient
syntax and has been long obsolete.  As usual, updating the tests is the nasty
part of this.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@133242 91177308-0d34-0410-b5e6-96231b3b80d8
2011-06-17 06:36:20 +00:00
Andrew Trick
104f4adeac Test case and comment for PR9633.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130294 91177308-0d34-0410-b5e6-96231b3b80d8
2011-04-27 05:42:17 +00:00
Andrew Trick
c343c1e27e Propagate SCEV no-wrap flags whenever possible.
This needs review.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127638 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-15 00:37:00 +00:00
Andrew Trick
e62289b98f When SCEV can determine the loop test is X < X, set ExactBECount=0.
When ExactBECount is a constant, use it for MaxBECount.
When MaxBECount cannot be computed, replace it with ExactBECount.
Fixes PR9424.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127342 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-09 17:29:58 +00:00
Chris Lattner
8ebaf90958 teach SCEV that the scale and addition of an inbounds gep don't NSW.
This fixes a FIXME in scev-aa.ll (allowing a new no-alias result) and
generally makes things more precise.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125449 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-13 03:14:49 +00:00
Chris Lattner
1021236c74 Per discussion with Dan G, inbounds geps *certainly* can have
unsigned overflow (e.g. "gep P, -1"), and while they can have
signed wrap in theoretical situations, modelling an AddRec as
not having signed wrap is going enough for any case we can 
think of today.  In the future if this isn't enough, we can
revisit this.  Modeling them as having NUW isn't causing any
known problems either FWIW.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125410 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-11 21:43:33 +00:00
Nick Lewycky
76167af9b1 Simplify some code with no functionality change. Make the test a lot more
robust against smarter optimizations, using the power of FileCheck.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124081 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-23 20:06:05 +00:00
Nick Lewycky
630d85a78c Use value ranges to fold ext(trunc) in SCEV when possible.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124062 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-23 06:20:19 +00:00
Tobias Grosser
e906921480 Implement requiredTransitive
The PassManager did not implement the transitivity of requiredTransitive. This
was unnoticed since 2006.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123942 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-20 21:03:22 +00:00
Nick Lewycky
5c6fc1cab7 Similarly, analyze truncate through multiply.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123842 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-19 18:56:00 +00:00
Nick Lewycky
30aa8b13c9 Add a missed SCEV fold that is required to continue analyzing the IR produced
by indvars through the scev expander.

trunc(add x, y) --> add(trunc x, y). Currently SCEV largely folds the other way
which is probably wrong, but preserved to minimize churn. Instcombine doesn't
do this fold either, demonstrating a missed optz'n opportunity on code doing
add+trunc+add.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123838 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-19 16:59:46 +00:00
Nick Lewycky
73f565e754 Add a missing SCEV simplification sext(zext x) --> zext x.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123832 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-19 15:56:12 +00:00
Eric Christopher
48eec43fdb Revert the testcase from the previous reverted commit.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123227 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-11 09:20:44 +00:00
Chris Lattner
e70d7c2201 add a testcase I missed in previous commit.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123143 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-09 23:52:31 +00:00
Chris Lattner
6d5a2411aa teach SCEV analysis of PHI nodes that PHI recurences formed
with GEP instructions are always NUW, because PHIs cannot wrap
the end of the address space.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123105 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-09 02:28:48 +00:00
Chris Lattner
f1859891b7 reduce indentation. Print <nuw> and <nsw> when dumping SCEV AddRec's
that have the bit set.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123104 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-09 02:16:18 +00:00
Chris Lattner
042ff0358d remove some noise from tests.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112889 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-02 22:35:33 +00:00
Dan Gohman
4ee87398e8 When analyzing loop exit conditions combined with and and or, don't
make any assumptions about when the two conditions will agree on when
to permit the loop to exit. This fixes PR7845.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@110758 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-11 00:12:36 +00:00
Dan Gohman
70eff63008 Revert the part of r107257 which introduced new logic for using
nsw and nuw flags from IR Instructions. On further consideration,
this isn't valid.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107298 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-30 17:27:11 +00:00
Dan Gohman
3e7f7cbea9 Add a testcase for scev-aa's new capability.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107258 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-30 07:17:47 +00:00
Dan Gohman
9d4588ffad Allow "exhaustive" trip count evaluation on phi nodes with all
constant operands.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106537 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-22 13:15:46 +00:00
Dan Gohman
b92654d9c9 Fix ScalarEvolution's "exhaustive" trip count evaluation code to avoid
assuming that loops are in canonical form, as ScalarEvolution doesn't
depend on LoopSimplify itself. Also, with indirectbr not all loops can
be simplified. This fixes PR7416.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106389 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-19 14:17:24 +00:00
Dan Gohman
3bf63768e5 Revert r106304 (105548 and friends), which are the SCEVComplexityCompare
optimizations. There is still some nondeterminism remaining.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106306 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-18 19:54:20 +00:00
Dan Gohman
78db186d2d Reapply 105540, 105542, and 105548, and revert r105732.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106304 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-18 19:26:04 +00:00
Daniel Dunbar
ced8db2a2b Workaround SCEV non-determinism on this test, for now, to get buildbots back to
green. Dan, please revert this once the real problem is fixed.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@105732 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-09 17:54:40 +00:00
Dan Gohman
4d52c6d622 Optimize ScalarEvolution's SCEVComplexityCompare predicate: don't go
scrounging through SCEVUnknown contents and SCEVNAryExpr operands;
instead just do a simple deterministic comparison of the precomputed
hash data.

Also, since this is more precise, it eliminates the need for the slow
N^2 duplicate detection code.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@105540 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-07 19:06:13 +00:00
Dan Gohman
585c40129f Add a comment to this test.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102387 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-26 21:37:43 +00:00
Dan Gohman
9f93d30a26 ScalarEvolution support for <= and >= loops.
Also, generalize ScalarEvolutions's min and max recognition to handle
some new forms of min and max that this change makes more common.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102234 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-24 03:09:42 +00:00