mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2024-08-23 17:29:19 +00:00
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 |
||
---|---|---|
.. | ||
BasicAA | ||
BlockFrequencyInfo | ||
BranchProbabilityInfo | ||
CallGraph | ||
Dominators | ||
GlobalsModRef | ||
LoopDependenceAnalysis | ||
LoopInfo | ||
PostDominators | ||
Profiling | ||
RegionInfo | ||
ScalarEvolution | ||
TypeBasedAliasAnalysis |