From 0984ca425e1c02b1a273a8648b1fa773dcf89489 Mon Sep 17 00:00:00 2001 From: Krzysztof Parzyszek Date: Tue, 26 Jul 2016 19:17:13 +0000 Subject: [PATCH] [Hexagon] Gracefully handle reg class mismatch in HexagonLoopReschedule llvm-svn: 276793 --- lib/Target/Hexagon/HexagonBitSimplify.cpp | 32 ++++++++++++-------- test/CodeGen/Hexagon/bit-loop-rc-mismatch.ll | 30 ++++++++++++++++++ 2 files changed, 49 insertions(+), 13 deletions(-) create mode 100644 test/CodeGen/Hexagon/bit-loop-rc-mismatch.ll diff --git a/lib/Target/Hexagon/HexagonBitSimplify.cpp b/lib/Target/Hexagon/HexagonBitSimplify.cpp index e6a03aa5ad5..c847fc165c2 100644 --- a/lib/Target/Hexagon/HexagonBitSimplify.cpp +++ b/lib/Target/Hexagon/HexagonBitSimplify.cpp @@ -2382,8 +2382,8 @@ namespace { struct PhiInfo { PhiInfo(MachineInstr &P, MachineBasicBlock &B); unsigned DefR; - BitTracker::RegisterRef LR, PR; - MachineBasicBlock *LB, *PB; + BitTracker::RegisterRef LR, PR; // Loop Register, Preheader Register + MachineBasicBlock *LB, *PB; // Loop Block, Preheader Block }; static unsigned getDefReg(const MachineInstr *MI); @@ -2742,31 +2742,37 @@ bool HexagonLoopRescheduling::processLoop(LoopCand &C) { auto F = std::find_if(Phis.begin(), Phis.end(), LoopInpEq); if (F == Phis.end()) continue; - unsigned PredR = 0; - if (!isSameShuffle(G.Out.Reg, G.Inp.Reg, F->PR.Reg, PredR)) { - const MachineInstr *DefPredR = MRI->getVRegDef(F->PR.Reg); - unsigned Opc = DefPredR->getOpcode(); + unsigned PrehR = 0; + if (!isSameShuffle(G.Out.Reg, G.Inp.Reg, F->PR.Reg, PrehR)) { + const MachineInstr *DefPrehR = MRI->getVRegDef(F->PR.Reg); + unsigned Opc = DefPrehR->getOpcode(); if (Opc != Hexagon::A2_tfrsi && Opc != Hexagon::A2_tfrpi) continue; - if (!DefPredR->getOperand(1).isImm()) + if (!DefPrehR->getOperand(1).isImm()) continue; - if (DefPredR->getOperand(1).getImm() != 0) + if (DefPrehR->getOperand(1).getImm() != 0) continue; const TargetRegisterClass *RC = MRI->getRegClass(G.Inp.Reg); if (RC != MRI->getRegClass(F->PR.Reg)) { - PredR = MRI->createVirtualRegister(RC); + PrehR = MRI->createVirtualRegister(RC); unsigned TfrI = (RC == &Hexagon::IntRegsRegClass) ? Hexagon::A2_tfrsi : Hexagon::A2_tfrpi; auto T = C.PB->getFirstTerminator(); DebugLoc DL = (T != C.PB->end()) ? T->getDebugLoc() : DebugLoc(); - BuildMI(*C.PB, T, DL, HII->get(TfrI), PredR) + BuildMI(*C.PB, T, DL, HII->get(TfrI), PrehR) .addImm(0); } else { - PredR = F->PR.Reg; + PrehR = F->PR.Reg; } } - assert(MRI->getRegClass(PredR) == MRI->getRegClass(G.Inp.Reg)); - moveGroup(G, *F->LB, *F->PB, F->LB->getFirstNonPHI(), F->DefR, PredR); + // isSameShuffle could match with PrehR being of a wider class than + // G.Inp.Reg, for example if G shuffles the low 32 bits of its input, + // it would match for the input being a 32-bit register, and PrehR + // being a 64-bit register (where the low 32 bits match). This could + // be handled, but for now skip these cases. + if (MRI->getRegClass(PrehR) != MRI->getRegClass(G.Inp.Reg)) + continue; + moveGroup(G, *F->LB, *F->PB, F->LB->getFirstNonPHI(), F->DefR, PrehR); Changed = true; } diff --git a/test/CodeGen/Hexagon/bit-loop-rc-mismatch.ll b/test/CodeGen/Hexagon/bit-loop-rc-mismatch.ll new file mode 100644 index 00000000000..db57998aeb6 --- /dev/null +++ b/test/CodeGen/Hexagon/bit-loop-rc-mismatch.ll @@ -0,0 +1,30 @@ +; RUN: llc -march=hexagon < %s +; REQUIRES: asserts + +target datalayout = "e-m:e-p:32:32:32-a:0-n16:32-i64:64:64-i32:32:32-i16:16:16-i1:8:8-f32:32:32-f64:64:64-v32:32:32-v64:64:64-v512:512:512-v1024:1024:1024-v2048:2048:2048" +target triple = "hexagon" + +define weak_odr hidden i32 @fred(i32* %this, i32* nocapture readonly dereferenceable(4) %__k) #0 align 2 { +entry: + %call = tail call i64 @danny(i32* %this, i32* nonnull dereferenceable(4) %__k) #2 + %__p.sroa.0.0.extract.trunc = trunc i64 %call to i32 + br i1 undef, label %for.end, label %for.body + +for.body: ; preds = %for.body, %entry + %__p.sroa.0.018 = phi i32 [ %call8, %for.body ], [ %__p.sroa.0.0.extract.trunc, %entry ] + %call8 = tail call i32 @sammy(i32* %this, i32 %__p.sroa.0.018) #2 + %0 = inttoptr i32 %call8 to i32* + %lnot.i = icmp eq i32* %0, undef + br i1 %lnot.i, label %for.end, label %for.body + +for.end: ; preds = %for.body, %entry + ret i32 0 +} + +declare hidden i64 @danny(i32*, i32* nocapture readonly dereferenceable(4)) #1 align 2 +declare hidden i32 @sammy(i32* nocapture, i32) #0 align 2 + +attributes #0 = { nounwind optsize "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="hexagonv60" "target-features"="+hvx,-hvx-double" "unsafe-fp-math"="false" "use-soft-float"="false" } +attributes #1 = { nounwind optsize readonly "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="hexagonv60" "target-features"="+hvx,-hvx-double" "unsafe-fp-math"="false" "use-soft-float"="false" } +attributes #2 = { optsize } +