llvm-6502/test/Analysis/ScalarEvolution
Andrew Trick 10bb82e54f Rewrite SCEV's backedge taken count computation.
Patch by Michele Scandale!

Rewrite of the functions used to compute the backedge taken count of a
loop on LT and GT comparisons.

I decided to split the handling of LT and GT cases becasue the trick
"a > b == -a < -b" in some cases prevents the trip count computation
due to the multiplication by -1 on the two operands of the
comparison. This issue comes from the conservative computation of
value range of SCEVs: taking the negative SCEV of an expression that
have a small positive range (e.g. [0,31]), we would have a SCEV with a
fullset as value range.

Indeed, in the new rewritten function I tried to better handle the
maximum backedge taken count computation when MAX/MIN expression are
used to handle the cases where no entry guard is found.

Some test have been modified in order to check the new value correctly
(I manually check them and reasoning on possible overflow the new
values seem correct).

I finally added a new test case related to the multiplication by -1
issue on GT comparisons.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194116 91177308-0d34-0410-b5e6-96231b3b80d8
2013-11-06 02:08:26 +00:00
..
2007-07-15-NegativeStride.ll FileCheckize some of the testcases. 2013-08-05 23:43:18 +00:00
2007-08-06-MisinterpretBranch.ll FileCheck-ize tests. 2013-08-22 00:51:19 +00:00
2007-08-06-Unsigned.ll FileCheck-ize tests. 2013-08-22 00:51:19 +00:00
2007-09-27-LargeStepping.ll FileCheck-ize tests. 2013-08-22 00:51:19 +00:00
2007-11-14-SignedAddRec.ll FileCheck-ize tests. 2013-08-22 00:51:19 +00:00
2007-11-18-OrInstruction.ll
2008-02-11-ReversedCondition.ll FileCheck-ize tests. 2013-08-22 00:51:19 +00:00
2008-02-12-SMAXTripCount.ll Filecheckize. 2011-11-29 02:05:23 +00:00
2008-02-15-UMax.ll FileCheck-ize tests. 2013-08-22 00:51:19 +00:00
2008-05-25-NegativeStepToZero.ll FileCheck-ize tests. 2013-08-22 00:51:19 +00:00
2008-06-12-BinomialInt64.ll
2008-07-12-UnneededSelect1.ll FileCheck-ize tests. 2013-08-22 00:51:19 +00:00
2008-07-12-UnneededSelect2.ll FileCheck-ize tests. 2013-08-22 00:51:19 +00:00
2008-07-19-InfiniteLoop.ll FileCheck-ize tests. 2013-08-22 00:51:19 +00:00
2008-07-19-WrappingIV.ll FileCheck-ize tests. 2013-08-22 00:51:19 +00:00
2008-07-29-SGTTripCount.ll
2008-07-29-SMinExpr.ll
2008-08-04-IVOverflow.ll
2008-08-04-LongAddRec.ll
2008-11-02-QuadraticCrash.ll
2008-11-15-CubicOOM.ll
2008-11-18-LessThanOrEqual.ll FileCheck-ize tests. 2013-08-22 00:51:19 +00:00
2008-11-18-Stride1.ll Rewrite SCEV's backedge taken count computation. 2013-11-06 02:08:26 +00:00
2008-11-18-Stride2.ll Rewrite SCEV's backedge taken count computation. 2013-11-06 02:08:26 +00:00
2008-12-08-FiniteSGE.ll FileCheck-ize tests. 2013-08-22 00:51:19 +00:00
2008-12-11-SMaxOverflow.ll
2008-12-14-StrideAndSigned.ll FileCheck-ize tests. 2013-08-22 00:51:19 +00:00
2008-12-15-DontUseSDiv.ll Rewrite SCEV's backedge taken count computation. 2013-11-06 02:08:26 +00:00
2009-01-02-SignedNegativeStride.ll FileCheck-ize tests. 2013-08-22 00:51:19 +00:00
2009-04-22-TruncCast.ll FileCheck-ize tests. 2013-08-22 00:51:19 +00:00
2009-05-09-PointerEdgeCount.ll FileCheck-ize tests. 2013-08-22 00:51:19 +00:00
2009-07-04-GroupConstantsWidthMismatch.ll
2010-09-03-RequiredTransitive.ll Add a check to the test Analysis/ScalarEvolution/2010-09-03-RequiredTransitive.ll 2012-12-30 01:42:34 +00:00
2011-03-09-ExactNoMaxBECount.ll Tests: rewrite 'opt ... %s' to 'opt ... < %s' so that opt does not emit a ModuleID 2012-12-30 02:33:22 +00:00
2011-04-26-FoldAddRec.ll Add newlines at end of test files, no functionality change 2013-07-13 22:00:58 +00:00
2011-10-04-ConstEvolve.ll
2012-03-26-LoadConstant.ll TBAA: remove !tbaa from testing cases if not used. 2013-04-29 22:42:01 +00:00
2012-05-18-LoopPredRecurse.ll SCEV: Add MarkPendingLoopPredicates to avoid recursive isImpliedCond. 2012-05-19 00:48:25 +00:00
2012-05-29-MulAddRec.ll Fix broken check lines. 2012-08-17 12:28:26 +00:00
and-xor.ll FileCheck-ize tests. 2013-08-22 00:51:19 +00:00
avoid-infinite-recursion-0.ll
avoid-infinite-recursion-1.ll
avoid-smax-0.ll FileCheck-ize tests. 2013-08-22 00:51:19 +00:00
avoid-smax-1.ll Test scalar evolution directly instead of testing the result of 2012-03-22 17:09:31 +00:00
div-overflow.ll FileCheck-ize tests. 2013-08-22 00:51:19 +00:00
do-loop.ll FileCheck-ize tests. 2013-08-22 00:51:19 +00:00
fold.ll Tests: rewrite 'opt ... %s' to 'opt ... < %s' so that opt does not emit a ModuleID 2012-12-30 01:28:40 +00:00
how-far-to-zero.ll If the step value is a constant zero, the loop isn't going to terminate. Fixes 2012-06-28 23:44:57 +00:00
load.ll 2>&1 doesn't work here, it just creates an empty file called "&1" 2011-10-27 18:27:45 +00:00
max-trip-count-address-space.ll Teach ScalarEvolution about pointer address spaces 2013-09-10 19:55:24 +00:00
max-trip-count.ll
nsw-offset.ll Revert "SCEV: When expanding a GEP the final addition to the base pointer has NUW but not NSW." 2012-04-17 06:33:57 +00:00
nsw.ll SCEV: Make the final add of an inbounds GEP nuw if we know that the index is positive. 2013-10-28 07:30:06 +00:00
pointer-sign-bits.ll
pr3909.ll
scev-aa.ll Convert the uses of '|&' to use '2>&1 |' instead, which works on old 2012-07-02 18:37:59 +00:00
scev-invalid.ll Fix SCEV forgetMemoizedResults should search and destroy backedge exprs. 2013-03-26 03:14:53 +00:00
sext-inreg.ll Convert all tests using TCL-style quoting to use shell-style quoting. 2012-07-02 12:47:22 +00:00
sext-iv-0.ll
sext-iv-1.ll Convert all tests using TCL-style quoting to use shell-style quoting. 2012-07-02 12:47:22 +00:00
sext-iv-2.ll
sle.ll
smax.ll FileCheckize some of the testcases. 2013-08-05 23:43:18 +00:00
SolveQuadraticEquation.ll FileCheckize some of the testcases. 2013-08-05 23:43:18 +00:00
trip-count2.ll FileCheckize some of the testcases. 2013-08-05 23:43:18 +00:00
trip-count3.ll Rewrite SCEV's backedge taken count computation. 2013-11-06 02:08:26 +00:00
trip-count4.ll FileCheckize some of the testcases. 2013-08-05 23:43:18 +00:00
trip-count5.ll Convert all tests using TCL-style quoting to use shell-style quoting. 2012-07-02 12:47:22 +00:00
trip-count6.ll FileCheckize some of the testcases. 2013-08-05 23:43:18 +00:00
trip-count7.ll FileCheckize some of the testcases. 2013-08-05 23:43:18 +00:00
trip-count8.ll FileCheckize some of the testcases. 2013-08-05 23:43:18 +00:00
trip-count9.ll Rewrite SCEV's backedge taken count computation. 2013-11-06 02:08:26 +00:00
trip-count10.ll Unit test for SCEV fix r182989, PR16130. 2013-05-31 16:42:41 +00:00
trip-count11.ll Fix creating bitcasts between address spaces in SCEV. 2013-10-21 18:41:10 +00:00
trip-count12.ll Don't forget to check FlagNW when determining whether an AddRecExpr will wrap 2011-11-09 07:11:37 +00:00
trip-count.ll FileCheckize some of the testcases. 2013-08-05 23:43:18 +00:00
undefined.ll
unreachable-code.ll
unsimplified-loop.ll
xor-and.ll FileCheckize some of the testcases. 2013-08-05 23:43:18 +00:00
zext-wrap.ll FileCheckize some of the testcases. 2013-08-05 23:43:18 +00:00