llvm-6502/test/Analysis
Sanjoy Das a0a0b40aa3 Bugfix: SCEVExpander incorrectly marks increment operations as no-wrap
(The change was landed in r230280 and caused the regression PR22674.
This version contains a fix and a test-case for PR22674).
    
When emitting the increment operation, SCEVExpander marks the
operation as nuw or nsw based on the flags on the preincrement SCEV.
This is incorrect because, for instance, it is possible that {-6,+,1}
is <nuw> while {-6,+,1}+1 = {-5,+,1} is not.
    
This change teaches SCEV to mark the increment as nuw/nsw only if it
can explicitly prove that the increment operation won't overflow.
    
Apart from the attached test case, another (more realistic)
manifestation of the bug can be seen in
Transforms/IndVarSimplify/pr20680.ll.

Differential Revision: http://reviews.llvm.org/D7778



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230533 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-25 20:02:59 +00:00
..
AssumptionCache [PM] Actually add the new pass manager support for the assumption cache. 2015-01-22 21:53:09 +00:00
BasicAA [BasicAA] Try to disambiguate GEPs through arrays of structs into 2015-02-07 17:04:29 +00:00
BlockFrequencyInfo IR: Make metadata typeless in assembly 2014-12-15 19:07:53 +00:00
BranchProbabilityInfo IR: Make metadata typeless in assembly 2014-12-15 19:07:53 +00:00
CallGraph
CFLAliasAnalysis Fixed a bug where CFLAA would crash the compiler. 2015-02-12 03:07:07 +00:00
CostModel [x86,sdag] Two interrelated changes to the x86 and sdag code. 2015-02-19 10:36:19 +00:00
Delinearization
DependenceAnalysis
Dominators [PM] Port domtree to the new pass manager (at last). 2015-01-14 10:19:28 +00:00
GlobalsModRef
LazyCallGraph
Lint Adding support for llvm.eh.begincatch and llvm.eh.endcatch intrinsics and beginning the documentation of native Windows exception handling. 2015-02-10 19:52:43 +00:00
LoopAccessAnalysis [LoopAccesses] Add -analyze support 2015-02-19 19:15:19 +00:00
LoopInfo [PM] Port LoopInfo to the new pass manager, adding both a LoopAnalysis 2015-01-20 10:58:50 +00:00
MemoryDependenceAnalysis
PostDominators
RegionInfo
ScalarEvolution Bugfix: SCEVExpander incorrectly marks increment operations as no-wrap 2015-02-25 20:02:59 +00:00
ScopedNoAliasAA IR: Make metadata typeless in assembly 2014-12-15 19:07:53 +00:00
TypeBasedAliasAnalysis Re-reapply r221924: "[GVN] Perform Scalar PRE on gep indices that feed loads before 2015-01-09 19:19:56 +00:00
ValueTracking MemDerefPrinter: Require DataLayoutPass for higher accuracy 2015-02-09 21:50:03 +00:00