Attachment 84880 Details for Bug 68224 – SGPR register spilling patch

[patch] SGPR register spilling patch

0001-XXX-WIP-Register-spilling.patch (text/plain), 11.85 KB, created by Tom Stellard on 2013-08-29 18:55:35 UTC

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Creator: Tom Stellard

Created: 2013-08-29 18:55:35 UTC

Size: 11.85 KB

patch

obsolete

>From 5469f35b06c0f3f277f37da3f75261a302e5818b Mon Sep 17 00:00:00 2001
>From: Tom Stellard <thomas.stellard@amd.com>
>Date: Thu, 29 Aug 2013 11:43:01 -0700
>Subject: [PATCH] XXX: WIP Register spilling
>
>---
> lib/Target/R600/AMDGPUInstrInfo.h         | 20 ++++-----
> lib/Target/R600/SIInstrInfo.cpp           | 70 +++++++++++++++++++++++++++++++
> lib/Target/R600/SIInstrInfo.h             | 12 ++++++
> lib/Target/R600/SIMachineFunctionInfo.cpp | 35 +++++++++++++++-
> lib/Target/R600/SIMachineFunctionInfo.h   | 27 ++++++++++++
> lib/Target/R600/SIRegisterInfo.cpp        | 26 ++++++++++++
> lib/Target/R600/SIRegisterInfo.h          |  2 +
> 7 files changed, 181 insertions(+), 11 deletions(-)
>
>diff --git a/lib/Target/R600/AMDGPUInstrInfo.h b/lib/Target/R600/AMDGPUInstrInfo.h
>index 306f467..0088fb6 100644
>--- a/lib/Target/R600/AMDGPUInstrInfo.h
>+++ b/lib/Target/R600/AMDGPUInstrInfo.h
>@@ -77,16 +77,16 @@ public:
>                            unsigned DestReg, unsigned SrcReg,
>                            bool KillSrc) const = 0;
> 
>-  void storeRegToStackSlot(MachineBasicBlock &MBB,
>-                           MachineBasicBlock::iterator MI,
>-                           unsigned SrcReg, bool isKill, int FrameIndex,
>-                           const TargetRegisterClass *RC,
>-                           const TargetRegisterInfo *TRI) const;
>-  void loadRegFromStackSlot(MachineBasicBlock &MBB,
>-                            MachineBasicBlock::iterator MI,
>-                            unsigned DestReg, int FrameIndex,
>-                            const TargetRegisterClass *RC,
>-                            const TargetRegisterInfo *TRI) const;
>+  virtual void storeRegToStackSlot(MachineBasicBlock &MBB,
>+                                   MachineBasicBlock::iterator MI,
>+                                   unsigned SrcReg, bool isKill, int FrameIndex,
>+                                   const TargetRegisterClass *RC,
>+                                   const TargetRegisterInfo *TRI) const;
>+  virtual void loadRegFromStackSlot(MachineBasicBlock &MBB,
>+                                    MachineBasicBlock::iterator MI,
>+                                    unsigned DestReg, int FrameIndex,
>+                                    const TargetRegisterClass *RC,
>+                                    const TargetRegisterInfo *TRI) const;
> 
> protected:
>   MachineInstr *foldMemoryOperandImpl(MachineFunction &MF,
>diff --git a/lib/Target/R600/SIInstrInfo.cpp b/lib/Target/R600/SIInstrInfo.cpp
>index e23eef3..83e059c 100644
>--- a/lib/Target/R600/SIInstrInfo.cpp
>+++ b/lib/Target/R600/SIInstrInfo.cpp
>@@ -16,6 +16,7 @@
> #include "SIInstrInfo.h"
> #include "AMDGPUTargetMachine.h"
> #include "SIDefines.h"
>+#include "SIMachineFunctionInfo.h"
> #include "llvm/CodeGen/MachineInstrBuilder.h"
> #include "llvm/CodeGen/MachineRegisterInfo.h"
> #include "llvm/MC/MCInstrDesc.h"
>@@ -182,6 +183,75 @@ unsigned SIInstrInfo::commuteOpcode(unsigned Opcode) const {
>   return Opcode;
> }
> 
>+void SIInstrInfo::storeRegToStackSlot(MachineBasicBlock &MBB,
>+                                      MachineBasicBlock::iterator MI,
>+                                      unsigned SrcReg, bool isKill,
>+                                      int FrameIndex,
>+                                      const TargetRegisterClass *RC,
>+                                      const TargetRegisterInfo *TRI) const {
>+  MachineRegisterInfo &MRI = MBB.getParent()->getRegInfo();
>+  SIMachineFunctionInfo *MFI = MBB.getParent()->getInfo<SIMachineFunctionInfo>();
>+  DebugLoc DL = MBB.findDebugLoc(MI);
>+  unsigned KillFlag = isKill ? RegState::Kill : 0;
>+
>+  if (RC == &AMDGPU::SReg_32RegClass) {
>+    if (RI.allUsesCopiedToVGPR(MRI, SrcReg)) {
>+      unsigned VReg = MRI.createVirtualRegister(&AMDGPU::VReg_32RegClass);
>+      BuildMI(MBB, MI, DL, get(AMDGPU::COPY), VReg)
>+             .addReg(SrcReg, KillFlag);
>+      MFI->SpillTracker.addSpilledReg(FrameIndex, VReg);
>+    } else {
>+      unsigned Lane = MFI->SpillTracker.getNextLane(MRI);
>+      BuildMI(MBB, MI, DL, get(AMDGPU::V_WRITELANE_B32_e32),
>+              MFI->SpillTracker.LaneVGPR)
>+              .addReg(SrcReg, KillFlag)
>+              .addImm(Lane);
>+      MFI->SpillTracker.addSpilledReg(FrameIndex, MFI->SpillTracker.LaneVGPR,
>+                                      Lane);
>+    }
>+  } else {
>+    for (unsigned i = 0, e = RC->getSize() / 4; i != e; ++i) {
>+      unsigned SubReg = MRI.createVirtualRegister(&AMDGPU::SReg_32RegClass);
>+      BuildMI(MBB, MI, MBB.findDebugLoc(MI), get(AMDGPU::COPY), SubReg)
>+              .addReg(SrcReg, 0, RI.getSubRegFromChannel(i));
>+      storeRegToStackSlot(MBB, MI, SubReg, isKill, FrameIndex + i,
>+                          &AMDGPU::SReg_32RegClass, TRI);
>+    }
>+  }
>+}
>+
>+void SIInstrInfo::loadRegFromStackSlot(MachineBasicBlock &MBB,
>+                                       MachineBasicBlock::iterator MI,
>+                                       unsigned DestReg, int FrameIndex,
>+                                       const TargetRegisterClass *RC,
>+                                       const TargetRegisterInfo *TRI) const {
>+  MachineRegisterInfo &MRI = MBB.getParent()->getRegInfo();
>+  SIMachineFunctionInfo *MFI = MBB.getParent()->getInfo<SIMachineFunctionInfo>();
>+  DebugLoc DL = MBB.findDebugLoc(MI);
>+  if (RC == &AMDGPU::SReg_32RegClass) {
>+     SIMachineFunctionInfo::SpilledReg Spill =
>+        MFI->SpillTracker.getSpilledReg(FrameIndex);
>+    assert(Spill.VGPR);
>+    if (!Spill.hasLane()) {
>+      BuildMI(MBB, MI, DL, get(AMDGPU::COPY), DestReg)
>+              .addReg(Spill.VGPR);
>+    } else {
>+      BuildMI(MBB, MI, DL, get(AMDGPU::V_READLANE_B32_e32), DestReg)
>+              .addReg(Spill.VGPR)
>+              .addImm(Spill.Lane);
>+    }
>+  } else {
>+    for (unsigned i = 0, e = RC->getSize() / 4; i != e; ++i) {
>+      unsigned SubReg = MRI.createVirtualRegister(&AMDGPU::SReg_32RegClass);
>+      loadRegFromStackSlot(MBB, MI, SubReg, FrameIndex + i,
>+                           &AMDGPU::SReg_32RegClass, TRI);
>+      BuildMI(MBB, MI, DL, get(AMDGPU::COPY))
>+              .addReg(DestReg, RegState::Define | RegState::Undef, RI.getSubRegFromChannel(i))
>+              .addReg(SubReg);
>+    }
>+  }
>+}
>+
> MachineInstr *SIInstrInfo::commuteInstruction(MachineInstr *MI,
>                                               bool NewMI) const {
> 
>diff --git a/lib/Target/R600/SIInstrInfo.h b/lib/Target/R600/SIInstrInfo.h
>index 87b8063..a61da96 100644
>--- a/lib/Target/R600/SIInstrInfo.h
>+++ b/lib/Target/R600/SIInstrInfo.h
>@@ -35,6 +35,18 @@ public:
>                            unsigned DestReg, unsigned SrcReg,
>                            bool KillSrc) const;
> 
>+  void storeRegToStackSlot(MachineBasicBlock &MBB,
>+                           MachineBasicBlock::iterator MI,
>+                           unsigned SrcReg, bool isKill, int FrameIndex,
>+                           const TargetRegisterClass *RC,
>+                           const TargetRegisterInfo *TRI) const;
>+
>+  void loadRegFromStackSlot(MachineBasicBlock &MBB,
>+                            MachineBasicBlock::iterator MI,
>+                            unsigned DestReg, int FrameIndex,
>+                            const TargetRegisterClass *RC,
>+                            const TargetRegisterInfo *TRI) const;
>+
>   unsigned commuteOpcode(unsigned Opcode) const;
> 
>   virtual MachineInstr *commuteInstruction(MachineInstr *MI,
>diff --git a/lib/Target/R600/SIMachineFunctionInfo.cpp b/lib/Target/R600/SIMachineFunctionInfo.cpp
>index ee0e307..86c5c97 100644
>--- a/lib/Target/R600/SIMachineFunctionInfo.cpp
>+++ b/lib/Target/R600/SIMachineFunctionInfo.cpp
>@@ -10,9 +10,42 @@
> 
> 
> #include "SIMachineFunctionInfo.h"
>+#include "SIRegisterInfo.h"
>+#include "llvm/CodeGen/MachineRegisterInfo.h"
>+
>+#define MAX_LANES 64
> 
> using namespace llvm;
> 
> SIMachineFunctionInfo::SIMachineFunctionInfo(const MachineFunction &MF)
>   : AMDGPUMachineFunction(MF),
>-    PSInputAddr(0) { }
>+    PSInputAddr(0),
>+    SpillTracker() { }
>+
>+static unsigned createLaneVGPR(MachineRegisterInfo &MRI) {
>+  return MRI.createVirtualRegister(&AMDGPU::VReg_32RegClass);
>+}
>+
>+unsigned SIMachineFunctionInfo::RegSpillTracker::getNextLane(MachineRegisterInfo &MRI) {
>+  if (!LaneVGPR) {
>+    LaneVGPR = createLaneVGPR(MRI);
>+  } else {
>+    CurrentLane++;
>+    if (CurrentLane == MAX_LANES) {
>+      CurrentLane = 0;
>+      LaneVGPR = createLaneVGPR(MRI);
>+    }
>+  }
>+  return CurrentLane;
>+}
>+
>+void SIMachineFunctionInfo::RegSpillTracker::addSpilledReg(unsigned FrameIndex,
>+                                                           unsigned Reg,
>+                                                           int Lane) {
>+  SpilledRegisters[FrameIndex] = SpilledReg(Reg, Lane);
>+}
>+
>+const SIMachineFunctionInfo::SpilledReg&
>+SIMachineFunctionInfo::RegSpillTracker::getSpilledReg(unsigned FrameIndex) {
>+  return SpilledRegisters[FrameIndex];
>+}
>diff --git a/lib/Target/R600/SIMachineFunctionInfo.h b/lib/Target/R600/SIMachineFunctionInfo.h
>index 6da9f7f..1f91450 100644
>--- a/lib/Target/R600/SIMachineFunctionInfo.h
>+++ b/lib/Target/R600/SIMachineFunctionInfo.h
>@@ -16,15 +16,42 @@
> #define SIMACHINEFUNCTIONINFO_H_
> 
> #include "AMDGPUMachineFunction.h"
>+#include <map>
> 
> namespace llvm {
> 
>+class MachineRegisterInfo;
>+
> /// This class keeps track of the SPI_SP_INPUT_ADDR config register, which
> /// tells the hardware which interpolation parameters to load.
> class SIMachineFunctionInfo : public AMDGPUMachineFunction {
> public:
>+
>+  struct SpilledReg {
>+    unsigned VGPR;
>+    int Lane;
>+    SpilledReg(unsigned R, int L) : VGPR (R), Lane (L) { }
>+    SpilledReg() : VGPR(0), Lane(-1) { }
>+    bool hasLane() { return Lane != -1;}
>+  };
>+
>+  struct RegSpillTracker {
>+  private:
>+    unsigned CurrentLane;
>+    std::map<unsigned, SpilledReg> SpilledRegisters;
>+  public:
>+    unsigned LaneVGPR;
>+    RegSpillTracker() : CurrentLane(0), SpilledRegisters(), LaneVGPR(0) { }
>+    unsigned getNextLane(MachineRegisterInfo &MRI);
>+    void addSpilledReg(unsigned FrameIndex, unsigned Reg, int Lane = -1);
>+    const SpilledReg& getSpilledReg(unsigned FrameIndex);
>+  };
>+
>+  // SIMachineFunctionInfo definition
>+
>   SIMachineFunctionInfo(const MachineFunction &MF);
>   unsigned PSInputAddr;
>+  struct RegSpillTracker SpillTracker;
> };
> 
> } // End namespace llvm
>diff --git a/lib/Target/R600/SIRegisterInfo.cpp b/lib/Target/R600/SIRegisterInfo.cpp
>index 5d12564..2422521 100644
>--- a/lib/Target/R600/SIRegisterInfo.cpp
>+++ b/lib/Target/R600/SIRegisterInfo.cpp
>@@ -15,6 +15,7 @@
> 
> #include "SIRegisterInfo.h"
> #include "AMDGPUTargetMachine.h"
>+#include "llvm/CodeGen/MachineRegisterInfo.h"
> 
> using namespace llvm;
> 
>@@ -81,3 +82,28 @@ bool SIRegisterInfo::isSGPRClass(const TargetRegisterClass *RC) const {
>          RC == &AMDGPU::SReg_256RegClass ||
>          RC == &AMDGPU::SReg_512RegClass;
> }
>+
>+bool SIRegisterInfo::allUsesCopiedToVGPR(const MachineRegisterInfo &MRI,
>+                                         unsigned Reg) const {
>+  if (MRI.use_empty(Reg)) {
>+    return false;
>+  }
>+  for (MachineRegisterInfo::use_iterator I = MRI.use_begin(Reg),
>+                                         E = MachineRegisterInfo::use_end();
>+                                         I != E; ++I) {
>+    MachineInstr &MI = *I;
>+    if (MI.getOpcode() != AMDGPU::COPY) {
>+      return false;
>+    }
>+    unsigned DstReg = MI.getOperand(0).getReg();
>+    // XXX: Copies to physical VGPR registers should be allowed.
>+    if (!TargetRegisterInfo::isVirtualRegister(DstReg)) {
>+      return false;
>+    }
>+    if (isSGPRClass(MRI.getRegClass(DstReg))) {
>+      return false;
>+    }
>+  }
>+  return true;
>+}
>+
>diff --git a/lib/Target/R600/SIRegisterInfo.h b/lib/Target/R600/SIRegisterInfo.h
>index ffc5797..9e0c602 100644
>--- a/lib/Target/R600/SIRegisterInfo.h
>+++ b/lib/Target/R600/SIRegisterInfo.h
>@@ -48,6 +48,8 @@ struct SIRegisterInfo : public AMDGPURegisterInfo {
> 
>   /// \returns true if this class contains only SGPR registers
>   bool isSGPRClass(const TargetRegisterClass *RC) const;
>+
>+  bool allUsesCopiedToVGPR(const MachineRegisterInfo &MRI, unsigned Reg) const;
> };
> 
> } // End namespace llvm
>-- 
>1.7.11.4
>

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Attachments on bug 68224: 84175 | 84473 | 84475 | 84543 | 84544 | 84551 | 84880 | 85372 | 89616 | 89631 | 89640 | 89659 | 89671 | 89680 | 89719 | 89806 | 89825 | 89853 | 89854 | 89954

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