Andrew Trick 4781d8ee1c indvars: Linear function test replace should avoid reusing undef. ... Fixes PR13371: indvars pass incorrectly substitutes 'undef' values. I do not like this fix. It's needed until/unless the meaning of undef changes. It attempts to be complete according to the IR spec, but I don't have much confidence in the implementation given the difficulty testing undefined behavior. Worse, this invalidates some of my hard-fought work on indvars and LSR to optimize pointer induction variables. It results benchmark regressions, which I'll track internally. On x86_64 no LTO I see: -3% huffbench -3% 400.perlbench -8% fhourstones My only suggestion for recovering is to change the meaning of undef. If we could trust an arbitrary instruction to produce a some real value that can be manipulated (e.g. incremented) according to non-undef rules, then this case could be easily handled with SCEV. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160421 91177308-0d34-0410-b5e6-96231b3b80d8		2012-07-18 04:35:10 +00:00
..
2002-09-09-PointerIndVar.ll
2003-04-16-ExprAnalysis.ll
2003-09-23-NotAtTop.ll
2003-12-10-RemoveInstrCrash.ll
2003-12-15-Crash.ll
2004-03-10-PHIInsertionBug.ll
2004-04-05-InvokeCastCrash.ll
2004-04-07-ScalarEvolutionCrash.ll
2005-02-11-InvokeCrash.ll
2005-02-17-TruncateExprCrash.ll
2005-02-26-ExitValueCompute.ll	Convert all tests using TCL-style quoting to use shell-style quoting.	2012-07-02 12:47:22 +00:00
2005-06-15-InstMoveCrash.ll
2005-11-18-Crash.ll
2006-03-31-NegativeStride.ll	Convert all tests using TCL-style quoting to use shell-style quoting.	2012-07-02 12:47:22 +00:00
2006-06-16-Indvar-LCSSA-Crash.ll
2006-09-20-LFTR-Crash.ll
2006-12-10-BitCast.ll
2007-01-06-TripCount.ll	Fix the remaining TCL-style quotes found in the testsuite. This is	2012-07-02 19:09:46 +00:00
2007-06-06-DeleteDanglesPtr.ll
2007-11-23-BitcastCrash.ll
2008-06-15-SCEVExpanderBug.ll
2008-09-02-IVType.ll
2008-10-03-CouldNotCompute.ll
2008-11-25-APFloatAssert.ll
2009-04-14-shorten_iv_vars.ll	Fix the remaining TCL-style quotes found in the testsuite. This is	2012-07-02 19:09:46 +00:00
2009-04-15-shorten-iv-vars-2.ll	Fix the remaining TCL-style quotes found in the testsuite. This is	2012-07-02 19:09:46 +00:00
2009-04-22-IndvarCrash.ll
2009-04-27-Floating.ll
2009-05-24-useafterfree.ll
2011-09-10-widen-nsw.ll	Remove redundant -enable-iv-rewrite=false flags from test cases.	2012-03-22 17:09:04 +00:00
2011-09-19-vectoriv.ll
2011-09-27-hoistsext.ll
2011-10-27-lftrnull.ll
2011-11-01-lftrptr.ll	Remove redundant -enable-iv-rewrite=false flags from test cases.	2012-03-22 17:09:04 +00:00
2011-11-15-multiexit.ll
2011-11-17-selfphi.ll
2012-07-17-lftr-undef.ll	indvars: Linear function test replace should avoid reusing undef.	2012-07-18 04:35:10 +00:00
ada-loops.ll	Remove redundant -enable-iv-rewrite=false flags from test cases.	2012-03-22 17:09:04 +00:00
ashr-tripcount.ll
avoid-i0.ll
casted-argument.ll
crash.ll
dangling-use.ll
divide-pointer.ll
elim-extend.ll	Remove redundant -enable-iv-rewrite=false flags from test cases.	2012-03-22 17:09:04 +00:00
eliminate-comparison.ll
eliminate-max.ll	Convert all tests using TCL-style quoting to use shell-style quoting.	2012-07-02 12:47:22 +00:00
eliminate-rem.ll
exit_value_tests.ll
floating-point-iv.ll
indirectbr.ll
interesting-invoke-use.ll
iterationCount_zext_or_trunc.ll
iv-fold.ll	Remove redundant -enable-iv-rewrite=false flags from test cases.	2012-03-22 17:09:04 +00:00
iv-sext.ll
iv-zext.ll	Remove redundant -enable-iv-rewrite=false flags from test cases.	2012-03-22 17:09:04 +00:00
lftr_simple.ll
lftr-other-uses.ll
lftr-promote.ll
lftr-reuse.ll	indvars: Linear function test replace should avoid reusing undef.	2012-07-18 04:35:10 +00:00
lit.local.cfg
loop_evaluate7.ll
loop_evaluate8.ll
loop_evaluate9.ll	Fix the remaining TCL-style quotes found in the testsuite. This is	2012-07-02 19:09:46 +00:00
loop_evaluate10.ll	Fix the remaining TCL-style quotes found in the testsuite. This is	2012-07-02 19:09:46 +00:00
loop_evaluate11.ll
loop_evaluate_1.ll
loop_evaluate_2.ll
loop_evaluate_3.ll	Convert all tests using TCL-style quoting to use shell-style quoting.	2012-07-02 12:47:22 +00:00
loop_evaluate_4.ll	Convert all tests using TCL-style quoting to use shell-style quoting.	2012-07-02 12:47:22 +00:00
loop_evaluate_5.ll	Convert all tests using TCL-style quoting to use shell-style quoting.	2012-07-02 12:47:22 +00:00
loop_evaluate_6.ll
masked-iv.ll
no-iv-rewrite.ll	Remove redundant -enable-iv-rewrite=false flags from test cases.	2012-03-22 17:09:04 +00:00
phi-uses-value-multiple-times.ll
polynomial-expand.ll
preserve-signed-wrap.ll	Remove redundant -enable-iv-rewrite=false flags from test cases.	2012-03-22 17:09:04 +00:00
promote-iv-to-eliminate-casts.ll
shrunk-constant.ll	Convert all tests using TCL-style quoting to use shell-style quoting.	2012-07-02 12:47:22 +00:00
signed-trip-count.ll
single-element-range.ll
sink-alloca.ll
sink-trapping.ll
tripcount_compute.ll
tripcount_infinite.ll
udiv.ll
uglygep.ll
ult-sub-to-eq.ll	Teach SCEV's icmp simplification logic that a-b == 0 is equivalent to a == b.	2012-05-30 18:32:23 +00:00
variable-stride-ivs-0.ll	Remove redundant -enable-iv-rewrite=false flags from test cases.	2012-03-22 17:09:04 +00:00
variable-stride-ivs-1.ll