From e8e2b8ae7b4af28fb0bf1bac8adea381005fa4d6 Mon Sep 17 00:00:00 2001 From: Quentin Colombet Date: Wed, 7 Jun 2017 00:22:07 +0000 Subject: [PATCH] [InlineSpiller] Only account for real spills in the hoisting logic Spills of undef values shouldn't impact the placement of the relevant spills. Drive by review. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@304850 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/CodeGen/InlineSpiller.cpp | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/lib/CodeGen/InlineSpiller.cpp b/lib/CodeGen/InlineSpiller.cpp index 68f2a2ed9a1..4e6a3ec2186 100644 --- a/lib/CodeGen/InlineSpiller.cpp +++ b/lib/CodeGen/InlineSpiller.cpp @@ -877,14 +877,16 @@ void InlineSpiller::insertSpill(unsigned NewVReg, bool isKill, MachineBasicBlock &MBB = *MI->getParent(); MachineInstrSpan MIS(MI); - if (isFullUndefDef(*MI)) + bool IsRealSpill = true; + if (isFullUndefDef(*MI)) { // Don't spill undef value. // Anything works for undef, in particular keeping the memory // uninitialized is a viable option and it saves code size and // run time. BuildMI(MBB, std::next(MI), MI->getDebugLoc(), TII.get(TargetOpcode::KILL)) .addReg(NewVReg, getKillRegState(isKill)); - else + IsRealSpill = false; + } else TII.storeRegToStackSlot(MBB, std::next(MI), NewVReg, isKill, StackSlot, MRI.getRegClass(NewVReg), &TRI); @@ -893,7 +895,8 @@ void InlineSpiller::insertSpill(unsigned NewVReg, bool isKill, DEBUG(dumpMachineInstrRangeWithSlotIndex(std::next(MI), MIS.end(), LIS, "spill")); ++NumSpills; - HSpiller.addToMergeableSpills(*std::next(MI), StackSlot, Original); + if (IsRealSpill) + HSpiller.addToMergeableSpills(*std::next(MI), StackSlot, Original); } /// spillAroundUses - insert spill code around each use of Reg. -- 2.40.0