llvm-6502/test/Analysis/BasicAA
Arnold Schwaighofer 3d5f96ee1b BasicAA: Recognize cyclic NoAlias phis
Enhances basic alias analysis to recognize phis whose first incoming values are
NoAlias and whose other incoming values are just the phi node itself through
some amount of recursion.

Example: With this change basicaa reports that ptr_phi and ptr_phi2 do not alias
each other.

bb:
 ptr = ptr2 + 1

loop:
  ptr_phi = phi [bb, ptr], [loop, ptr_plus_one]
  ptr2_phi = phi [bb, ptr2], [loop, ptr2_plus_one]
  ...
  ptr_plus_one = gep ptr_phi, 1
  ptr2_plus_one = gep ptr2_phi, 1

This enables the elimination of one load in code like the following:

extern int foo;

int test_noalias(int *ptr, int num, int* coeff) {
  int *ptr2 = ptr;
  int result = (*ptr++) * (*coeff--);
  while (num--) {
    *ptr2++ = *ptr;
    result +=  (*coeff--) * (*ptr++);
  }
  *ptr = foo;
  return result;
}

Part 2/2 of fix for PR13564.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@163319 91177308-0d34-0410-b5e6-96231b3b80d8
2012-09-06 14:41:53 +00:00
..
2003-02-26-AccessSizeTest.ll FileCheck-ize these tests. Harden some of them. 2012-04-24 09:15:38 +00:00
2003-03-04-GEPCrash.ll
2003-04-22-GEPProblem.ll FileCheck-ize these tests. Harden some of them. 2012-04-24 09:15:38 +00:00
2003-04-25-GEPCrash.ll
2003-05-21-GEP-Problem.ll
2003-06-01-AliasCrash.ll
2003-07-03-BasicAACrash.ll
2003-09-19-LocalArgument.ll FileCheck-ize these tests. Harden some of them. 2012-04-24 09:15:38 +00:00
2003-11-04-SimpleCases.ll Convert the uses of '|&' to use '2>&1 |' instead, which works on old 2012-07-02 18:37:59 +00:00
2003-12-11-ConstExprGEP.ll Convert the uses of '|&' to use '2>&1 |' instead, which works on old 2012-07-02 18:37:59 +00:00
2004-07-28-MustAliasbug.ll FileCheck-ize these tests. Harden some of them. 2012-04-24 09:15:38 +00:00
2006-03-03-BadArraySubscript.ll Convert the uses of '|&' to use '2>&1 |' instead, which works on old 2012-07-02 18:37:59 +00:00
2006-11-03-BasicAAVectorCrash.ll
2007-01-13-BasePointerBadNoAlias.ll FileCheck-ize these tests. Harden some of them. 2012-04-24 09:15:38 +00:00
2007-08-01-NoAliasAndCalls.ll Convert the uses of '|&' to use '2>&1 |' instead, which works on old 2012-07-02 18:37:59 +00:00
2007-08-01-NoAliasAndGEP.ll Convert the uses of '|&' to use '2>&1 |' instead, which works on old 2012-07-02 18:37:59 +00:00
2007-08-05-GetOverloadedModRef.ll FileCheck-ize these tests. Harden some of them. 2012-04-24 09:15:38 +00:00
2007-10-24-ArgumentsGlobals.ll FileCheck-ize these tests. Harden some of them. 2012-04-24 09:15:38 +00:00
2007-11-05-SizeCrash.ll
2007-12-08-OutOfBoundsCrash.ll
2008-04-15-Byval.ll FileCheck-ize these tests. Harden some of them. 2012-04-24 09:15:38 +00:00
2008-06-02-GEPTailCrash.ll
2008-11-23-NoaliasRet.ll Convert the uses of '|&' to use '2>&1 |' instead, which works on old 2012-07-02 18:37:59 +00:00
2009-03-04-GEPNoalias.ll FileCheck-ize these tests. Harden some of them. 2012-04-24 09:15:38 +00:00
2009-10-13-AtomicModRef.ll
2009-10-13-GEP-BaseNoAlias.ll Convert the uses of '|&' to use '2>&1 |' instead, which works on old 2012-07-02 18:37:59 +00:00
2010-09-15-GEP-SignedArithmetic.ll Convert the uses of '|&' to use '2>&1 |' instead, which works on old 2012-07-02 18:37:59 +00:00
aligned-overread.ll
args-rets-allocas-loads.ll Convert the uses of '|&' to use '2>&1 |' instead, which works on old 2012-07-02 18:37:59 +00:00
byval.ll FileCheck-ize these tests. Harden some of them. 2012-04-24 09:15:38 +00:00
cas.ll FileCheck-ize these tests. Harden some of them. 2012-04-24 09:15:38 +00:00
constant-over-index.ll Convert the uses of '|&' to use '2>&1 |' instead, which works on old 2012-07-02 18:37:59 +00:00
dag.ll Convert the uses of '|&' to use '2>&1 |' instead, which works on old 2012-07-02 18:37:59 +00:00
empty.ll Convert the uses of '|&' to use '2>&1 |' instead, which works on old 2012-07-02 18:37:59 +00:00
featuretest.ll
full-store-partial-alias.ll FileCheck-ize these tests. Harden some of them. 2012-04-24 09:15:38 +00:00
gcsetest.ll FileCheck-ize these tests. Harden some of them. 2012-04-24 09:15:38 +00:00
gep-alias.ll Convert the uses of '|&' to use '2>&1 |' instead, which works on old 2012-07-02 18:37:59 +00:00
getmodrefinfo-cs-cs.ll Convert the uses of '|&' to use '2>&1 |' instead, which works on old 2012-07-02 18:37:59 +00:00
global-size.ll
intrinsics.ll
lit.local.cfg
memset_pattern.ll
modref.ll
must-and-partial.ll Convert the uses of '|&' to use '2>&1 |' instead, which works on old 2012-07-02 18:37:59 +00:00
no-escape-call.ll FileCheck-ize these tests. Harden some of them. 2012-04-24 09:15:38 +00:00
noalias-geps.ll BasicAA: GEPs of NoAlias'ing base ptr with equivalent indices are NoAlias 2012-09-06 14:31:51 +00:00
nocapture.ll FileCheck-ize these tests. Harden some of them. 2012-04-24 09:15:38 +00:00
phi-aa.ll Convert the uses of '|&' to use '2>&1 |' instead, which works on old 2012-07-02 18:37:59 +00:00
phi-and-select.ll Convert the uses of '|&' to use '2>&1 |' instead, which works on old 2012-07-02 18:37:59 +00:00
phi-speculation.ll BasicAA: Recognize cyclic NoAlias phis 2012-09-06 14:41:53 +00:00
pure-const-dce.ll FileCheck-ize these tests. Harden some of them. 2012-04-24 09:15:38 +00:00
store-promote.ll
tailcall-modref.ll FileCheck-ize these tests. Harden some of them. 2012-04-24 09:15:38 +00:00
underlying-value.ll
unreachable-block.ll