diff options
Diffstat (limited to 'lib/Transforms/Scalar/LoopRerollPass.cpp')
| -rw-r--r-- | lib/Transforms/Scalar/LoopRerollPass.cpp | 17 |
1 files changed, 13 insertions, 4 deletions
diff --git a/lib/Transforms/Scalar/LoopRerollPass.cpp b/lib/Transforms/Scalar/LoopRerollPass.cpp index 9a99e5925572..166b57f20b43 100644 --- a/lib/Transforms/Scalar/LoopRerollPass.cpp +++ b/lib/Transforms/Scalar/LoopRerollPass.cpp @@ -1,9 +1,8 @@ //===- LoopReroll.cpp - Loop rerolling pass -------------------------------===// // -// The LLVM Compiler Infrastructure -// -// This file is distributed under the University of Illinois Open Source -// License. See LICENSE.TXT for details. +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception // //===----------------------------------------------------------------------===// // @@ -892,12 +891,22 @@ bool LoopReroll::DAGRootTracker::validateRootSet(DAGRootSet &DRS) { const auto *ADR = dyn_cast<SCEVAddRecExpr>(SE->getSCEV(DRS.BaseInst)); if (!ADR) return false; + + // Check that the first root is evenly spaced. unsigned N = DRS.Roots.size() + 1; const SCEV *StepSCEV = SE->getMinusSCEV(SE->getSCEV(DRS.Roots[0]), ADR); const SCEV *ScaleSCEV = SE->getConstant(StepSCEV->getType(), N); if (ADR->getStepRecurrence(*SE) != SE->getMulExpr(StepSCEV, ScaleSCEV)) return false; + // Check that the remainling roots are evenly spaced. + for (unsigned i = 1; i < N - 1; ++i) { + const SCEV *NewStepSCEV = SE->getMinusSCEV(SE->getSCEV(DRS.Roots[i]), + SE->getSCEV(DRS.Roots[i-1])); + if (NewStepSCEV != StepSCEV) + return false; + } + return true; } |