diff options
Diffstat (limited to 'lib/Transforms/Scalar/LoopStrengthReduce.cpp')
-rw-r--r-- | lib/Transforms/Scalar/LoopStrengthReduce.cpp | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/lib/Transforms/Scalar/LoopStrengthReduce.cpp b/lib/Transforms/Scalar/LoopStrengthReduce.cpp index 3c94616fe9..f99e303876 100644 --- a/lib/Transforms/Scalar/LoopStrengthReduce.cpp +++ b/lib/Transforms/Scalar/LoopStrengthReduce.cpp @@ -2811,6 +2811,9 @@ void LSRInstance::NarrowSearchSpaceUsingHeuristics() { bool Any = false; for (size_t i = 0, e = LU.Formulae.size(); i != e; ++i) { Formula &F = LU.Formulae[i]; + // Look for a formula with a constant or GV in a register. If the use + // also has a formula with that same value in an immediate field, + // delete the one that uses a register. for (SmallVectorImpl<const SCEV *>::const_iterator I = F.BaseRegs.begin(), E = F.BaseRegs.end(); I != E; ++I) { if (const SCEVConstant *C = dyn_cast<SCEVConstant>(*I)) { @@ -2861,6 +2864,8 @@ void LSRInstance::NarrowSearchSpaceUsingHeuristics() { "separated by a constant offset will use the same " "registers.\n"); + // This is especially useful for unrolled loops. + for (size_t LUIdx = 0, NumUses = Uses.size(); LUIdx != NumUses; ++LUIdx) { LSRUse &LU = Uses[LUIdx]; for (size_t FIdx = 0, NumForms = LU.Formulae.size(); @@ -3074,6 +3079,7 @@ void LSRInstance::Solve(SmallVectorImpl<const Formula *> &Solution) const { DenseSet<const SCEV *> VisitedRegs; Workspace.reserve(Uses.size()); + // SolveRecurse does all the work. SolveRecurse(Solution, SolutionCost, Workspace, CurCost, CurRegs, VisitedRegs); |