[llvm] r227770 - [PowerPC] Put PPCVSXFMAMutate into its own source file
Hal Finkel
hfinkel at anl.gov
Sun Feb 1 13:51:23 PST 2015
Author: hfinkel
Date: Sun Feb 1 15:51:22 2015
New Revision: 227770
URL: http://llvm.org/viewvc/llvm-project?rev=227770&view=rev
Log:
[PowerPC] Put PPCVSXFMAMutate into its own source file
PPCInstrInfo.cpp has ended up containing several small MI-level passes, and
this is making the file harder to read than necessary. Split out
PPCVSXFMAMutate into its own source file. NFC.
Added:
llvm/trunk/lib/Target/PowerPC/PPCVSXFMAMutate.cpp
Modified:
llvm/trunk/lib/Target/PowerPC/CMakeLists.txt
llvm/trunk/lib/Target/PowerPC/PPCInstrInfo.cpp
Modified: llvm/trunk/lib/Target/PowerPC/CMakeLists.txt
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/PowerPC/CMakeLists.txt?rev=227770&r1=227769&r2=227770&view=diff
==============================================================================
--- llvm/trunk/lib/Target/PowerPC/CMakeLists.txt (original)
+++ llvm/trunk/lib/Target/PowerPC/CMakeLists.txt Sun Feb 1 15:51:22 2015
@@ -30,6 +30,7 @@ add_llvm_target(PowerPCCodeGen
PPCTargetObjectFile.cpp
PPCTargetTransformInfo.cpp
PPCSelectionDAGInfo.cpp
+ PPCVSXFMAMutate.cpp
)
add_subdirectory(AsmParser)
Modified: llvm/trunk/lib/Target/PowerPC/PPCInstrInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/PowerPC/PPCInstrInfo.cpp?rev=227770&r1=227769&r2=227770&view=diff
==============================================================================
--- llvm/trunk/lib/Target/PowerPC/PPCInstrInfo.cpp (original)
+++ llvm/trunk/lib/Target/PowerPC/PPCInstrInfo.cpp Sun Feb 1 15:51:22 2015
@@ -52,9 +52,6 @@ opt<bool> DisableCTRLoopAnal("disable-pp
static cl::opt<bool> DisableCmpOpt("disable-ppc-cmp-opt",
cl::desc("Disable compare instruction optimization"), cl::Hidden);
-static cl::opt<bool> DisableVSXFMAMutate("disable-ppc-vsx-fma-mutation",
-cl::desc("Disable VSX FMA instruction mutation"), cl::Hidden);
-
static cl::opt<bool> VSXSelfCopyCrash("crash-on-ppc-vsx-self-copy",
cl::desc("Causes the backend to crash instead of generating a nop VSX copy"),
cl::Hidden);
@@ -1609,294 +1606,6 @@ unsigned PPCInstrInfo::GetInstSizeInByte
}
#undef DEBUG_TYPE
-#define DEBUG_TYPE "ppc-vsx-fma-mutate"
-
-namespace {
- // PPCVSXFMAMutate pass - For copies between VSX registers and non-VSX registers
- // (Altivec and scalar floating-point registers), we need to transform the
- // copies into subregister copies with other restrictions.
- struct PPCVSXFMAMutate : public MachineFunctionPass {
- static char ID;
- PPCVSXFMAMutate() : MachineFunctionPass(ID) {
- initializePPCVSXFMAMutatePass(*PassRegistry::getPassRegistry());
- }
-
- LiveIntervals *LIS;
- const PPCInstrInfo *TII;
-
-protected:
- bool processBlock(MachineBasicBlock &MBB) {
- bool Changed = false;
-
- MachineRegisterInfo &MRI = MBB.getParent()->getRegInfo();
- const TargetRegisterInfo *TRI = &TII->getRegisterInfo();
- for (MachineBasicBlock::iterator I = MBB.begin(), IE = MBB.end();
- I != IE; ++I) {
- MachineInstr *MI = I;
-
- // The default (A-type) VSX FMA form kills the addend (it is taken from
- // the target register, which is then updated to reflect the result of
- // the FMA). If the instruction, however, kills one of the registers
- // used for the product, then we can use the M-form instruction (which
- // will take that value from the to-be-defined register).
-
- int AltOpc = PPC::getAltVSXFMAOpcode(MI->getOpcode());
- if (AltOpc == -1)
- continue;
-
- // This pass is run after register coalescing, and so we're looking for
- // a situation like this:
- // ...
- // %vreg5<def> = COPY %vreg9; VSLRC:%vreg5,%vreg9
- // %vreg5<def,tied1> = XSMADDADP %vreg5<tied0>, %vreg17, %vreg16,
- // %RM<imp-use>; VSLRC:%vreg5,%vreg17,%vreg16
- // ...
- // %vreg9<def,tied1> = XSMADDADP %vreg9<tied0>, %vreg17, %vreg19,
- // %RM<imp-use>; VSLRC:%vreg9,%vreg17,%vreg19
- // ...
- // Where we can eliminate the copy by changing from the A-type to the
- // M-type instruction. Specifically, for this example, this means:
- // %vreg5<def,tied1> = XSMADDADP %vreg5<tied0>, %vreg17, %vreg16,
- // %RM<imp-use>; VSLRC:%vreg5,%vreg17,%vreg16
- // is replaced by:
- // %vreg16<def,tied1> = XSMADDMDP %vreg16<tied0>, %vreg18, %vreg9,
- // %RM<imp-use>; VSLRC:%vreg16,%vreg18,%vreg9
- // and we remove: %vreg5<def> = COPY %vreg9; VSLRC:%vreg5,%vreg9
-
- SlotIndex FMAIdx = LIS->getInstructionIndex(MI);
-
- VNInfo *AddendValNo =
- LIS->getInterval(MI->getOperand(1).getReg()).Query(FMAIdx).valueIn();
- MachineInstr *AddendMI = LIS->getInstructionFromIndex(AddendValNo->def);
-
- // The addend and this instruction must be in the same block.
-
- if (!AddendMI || AddendMI->getParent() != MI->getParent())
- continue;
-
- // The addend must be a full copy within the same register class.
-
- if (!AddendMI->isFullCopy())
- continue;
-
- unsigned AddendSrcReg = AddendMI->getOperand(1).getReg();
- if (TargetRegisterInfo::isVirtualRegister(AddendSrcReg)) {
- if (MRI.getRegClass(AddendMI->getOperand(0).getReg()) !=
- MRI.getRegClass(AddendSrcReg))
- continue;
- } else {
- // If AddendSrcReg is a physical register, make sure the destination
- // register class contains it.
- if (!MRI.getRegClass(AddendMI->getOperand(0).getReg())
- ->contains(AddendSrcReg))
- continue;
- }
-
- // In theory, there could be other uses of the addend copy before this
- // fma. We could deal with this, but that would require additional
- // logic below and I suspect it will not occur in any relevant
- // situations. Additionally, check whether the copy source is killed
- // prior to the fma. In order to replace the addend here with the
- // source of the copy, it must still be live here. We can't use
- // interval testing for a physical register, so as long as we're
- // walking the MIs we may as well test liveness here.
- bool OtherUsers = false, KillsAddendSrc = false;
- for (auto J = std::prev(I), JE = MachineBasicBlock::iterator(AddendMI);
- J != JE; --J) {
- if (J->readsVirtualRegister(AddendMI->getOperand(0).getReg())) {
- OtherUsers = true;
- break;
- }
- if (J->modifiesRegister(AddendSrcReg, TRI) ||
- J->killsRegister(AddendSrcReg, TRI)) {
- KillsAddendSrc = true;
- break;
- }
- }
-
- if (OtherUsers || KillsAddendSrc)
- continue;
-
- // Find one of the product operands that is killed by this instruction.
-
- unsigned KilledProdOp = 0, OtherProdOp = 0;
- if (LIS->getInterval(MI->getOperand(2).getReg())
- .Query(FMAIdx).isKill()) {
- KilledProdOp = 2;
- OtherProdOp = 3;
- } else if (LIS->getInterval(MI->getOperand(3).getReg())
- .Query(FMAIdx).isKill()) {
- KilledProdOp = 3;
- OtherProdOp = 2;
- }
-
- // If there are no killed product operands, then this transformation is
- // likely not profitable.
- if (!KilledProdOp)
- continue;
-
- // For virtual registers, verify that the addend source register
- // is live here (as should have been assured above).
- assert((!TargetRegisterInfo::isVirtualRegister(AddendSrcReg) ||
- LIS->getInterval(AddendSrcReg).liveAt(FMAIdx)) &&
- "Addend source register is not live!");
-
- // Transform: (O2 * O3) + O1 -> (O2 * O1) + O3.
-
- unsigned AddReg = AddendMI->getOperand(1).getReg();
- unsigned KilledProdReg = MI->getOperand(KilledProdOp).getReg();
- unsigned OtherProdReg = MI->getOperand(OtherProdOp).getReg();
-
- unsigned AddSubReg = AddendMI->getOperand(1).getSubReg();
- unsigned KilledProdSubReg = MI->getOperand(KilledProdOp).getSubReg();
- unsigned OtherProdSubReg = MI->getOperand(OtherProdOp).getSubReg();
-
- bool AddRegKill = AddendMI->getOperand(1).isKill();
- bool KilledProdRegKill = MI->getOperand(KilledProdOp).isKill();
- bool OtherProdRegKill = MI->getOperand(OtherProdOp).isKill();
-
- bool AddRegUndef = AddendMI->getOperand(1).isUndef();
- bool KilledProdRegUndef = MI->getOperand(KilledProdOp).isUndef();
- bool OtherProdRegUndef = MI->getOperand(OtherProdOp).isUndef();
-
- unsigned OldFMAReg = MI->getOperand(0).getReg();
-
- // The transformation doesn't work well with things like:
- // %vreg5 = A-form-op %vreg5, %vreg11, %vreg5;
- // so leave such things alone.
- if (OldFMAReg == KilledProdReg)
- continue;
-
- assert(OldFMAReg == AddendMI->getOperand(0).getReg() &&
- "Addend copy not tied to old FMA output!");
-
- DEBUG(dbgs() << "VSX FMA Mutation:\n " << *MI;);
-
- MI->getOperand(0).setReg(KilledProdReg);
- MI->getOperand(1).setReg(KilledProdReg);
- MI->getOperand(3).setReg(AddReg);
- MI->getOperand(2).setReg(OtherProdReg);
-
- MI->getOperand(0).setSubReg(KilledProdSubReg);
- MI->getOperand(1).setSubReg(KilledProdSubReg);
- MI->getOperand(3).setSubReg(AddSubReg);
- MI->getOperand(2).setSubReg(OtherProdSubReg);
-
- MI->getOperand(1).setIsKill(KilledProdRegKill);
- MI->getOperand(3).setIsKill(AddRegKill);
- MI->getOperand(2).setIsKill(OtherProdRegKill);
-
- MI->getOperand(1).setIsUndef(KilledProdRegUndef);
- MI->getOperand(3).setIsUndef(AddRegUndef);
- MI->getOperand(2).setIsUndef(OtherProdRegUndef);
-
- MI->setDesc(TII->get(AltOpc));
-
- DEBUG(dbgs() << " -> " << *MI);
-
- // The killed product operand was killed here, so we can reuse it now
- // for the result of the fma.
-
- LiveInterval &FMAInt = LIS->getInterval(OldFMAReg);
- VNInfo *FMAValNo = FMAInt.getVNInfoAt(FMAIdx.getRegSlot());
- for (auto UI = MRI.reg_nodbg_begin(OldFMAReg), UE = MRI.reg_nodbg_end();
- UI != UE;) {
- MachineOperand &UseMO = *UI;
- MachineInstr *UseMI = UseMO.getParent();
- ++UI;
-
- // Don't replace the result register of the copy we're about to erase.
- if (UseMI == AddendMI)
- continue;
-
- UseMO.setReg(KilledProdReg);
- UseMO.setSubReg(KilledProdSubReg);
- }
-
- // Extend the live intervals of the killed product operand to hold the
- // fma result.
-
- LiveInterval &NewFMAInt = LIS->getInterval(KilledProdReg);
- for (LiveInterval::iterator AI = FMAInt.begin(), AE = FMAInt.end();
- AI != AE; ++AI) {
- // Don't add the segment that corresponds to the original copy.
- if (AI->valno == AddendValNo)
- continue;
-
- VNInfo *NewFMAValNo =
- NewFMAInt.getNextValue(AI->start,
- LIS->getVNInfoAllocator());
-
- NewFMAInt.addSegment(LiveInterval::Segment(AI->start, AI->end,
- NewFMAValNo));
- }
- DEBUG(dbgs() << " extended: " << NewFMAInt << '\n');
-
- FMAInt.removeValNo(FMAValNo);
- DEBUG(dbgs() << " trimmed: " << FMAInt << '\n');
-
- // Remove the (now unused) copy.
-
- DEBUG(dbgs() << " removing: " << *AddendMI << '\n');
- LIS->RemoveMachineInstrFromMaps(AddendMI);
- AddendMI->eraseFromParent();
-
- Changed = true;
- }
-
- return Changed;
- }
-
-public:
- bool runOnMachineFunction(MachineFunction &MF) override {
- // If we don't have VSX then go ahead and return without doing
- // anything.
- const PPCSubtarget &STI = MF.getSubtarget<PPCSubtarget>();
- if (!STI.hasVSX())
- return false;
-
- LIS = &getAnalysis<LiveIntervals>();
-
- TII = STI.getInstrInfo();
-
- bool Changed = false;
-
- if (DisableVSXFMAMutate)
- return Changed;
-
- for (MachineFunction::iterator I = MF.begin(); I != MF.end();) {
- MachineBasicBlock &B = *I++;
- if (processBlock(B))
- Changed = true;
- }
-
- return Changed;
- }
-
- void getAnalysisUsage(AnalysisUsage &AU) const override {
- AU.addRequired<LiveIntervals>();
- AU.addPreserved<LiveIntervals>();
- AU.addRequired<SlotIndexes>();
- AU.addPreserved<SlotIndexes>();
- MachineFunctionPass::getAnalysisUsage(AU);
- }
- };
-}
-
-INITIALIZE_PASS_BEGIN(PPCVSXFMAMutate, DEBUG_TYPE,
- "PowerPC VSX FMA Mutation", false, false)
-INITIALIZE_PASS_DEPENDENCY(LiveIntervals)
-INITIALIZE_PASS_DEPENDENCY(SlotIndexes)
-INITIALIZE_PASS_END(PPCVSXFMAMutate, DEBUG_TYPE,
- "PowerPC VSX FMA Mutation", false, false)
-
-char &llvm::PPCVSXFMAMutateID = PPCVSXFMAMutate::ID;
-
-char PPCVSXFMAMutate::ID = 0;
-FunctionPass*
-llvm::createPPCVSXFMAMutatePass() { return new PPCVSXFMAMutate(); }
-
-#undef DEBUG_TYPE
#define DEBUG_TYPE "ppc-vsx-copy"
namespace llvm {
Added: llvm/trunk/lib/Target/PowerPC/PPCVSXFMAMutate.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/PowerPC/PPCVSXFMAMutate.cpp?rev=227770&view=auto
==============================================================================
--- llvm/trunk/lib/Target/PowerPC/PPCVSXFMAMutate.cpp (added)
+++ llvm/trunk/lib/Target/PowerPC/PPCVSXFMAMutate.cpp Sun Feb 1 15:51:22 2015
@@ -0,0 +1,336 @@
+//===--------------- PPCVSXFMAMutate.cpp - VSX FMA Mutation ---------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This pass mutates the form of VSX FMA instructions to avoid unnecessary
+// copies.
+//
+//===----------------------------------------------------------------------===//
+
+#include "PPCInstrInfo.h"
+#include "MCTargetDesc/PPCPredicates.h"
+#include "PPC.h"
+#include "PPCInstrBuilder.h"
+#include "PPCMachineFunctionInfo.h"
+#include "PPCTargetMachine.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/Statistic.h"
+#include "llvm/CodeGen/LiveIntervalAnalysis.h"
+#include "llvm/CodeGen/MachineFrameInfo.h"
+#include "llvm/CodeGen/MachineFunctionPass.h"
+#include "llvm/CodeGen/MachineInstrBuilder.h"
+#include "llvm/CodeGen/MachineMemOperand.h"
+#include "llvm/CodeGen/MachineRegisterInfo.h"
+#include "llvm/CodeGen/PseudoSourceValue.h"
+#include "llvm/CodeGen/ScheduleDAG.h"
+#include "llvm/CodeGen/SlotIndexes.h"
+#include "llvm/CodeGen/StackMaps.h"
+#include "llvm/MC/MCAsmInfo.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/TargetRegistry.h"
+#include "llvm/Support/raw_ostream.h"
+
+using namespace llvm;
+
+static cl::opt<bool> DisableVSXFMAMutate("disable-ppc-vsx-fma-mutation",
+cl::desc("Disable VSX FMA instruction mutation"), cl::Hidden);
+
+#define DEBUG_TYPE "ppc-vsx-fma-mutate"
+
+namespace llvm { namespace PPC {
+ int getAltVSXFMAOpcode(uint16_t Opcode);
+} }
+
+namespace {
+ // PPCVSXFMAMutate pass - For copies between VSX registers and non-VSX registers
+ // (Altivec and scalar floating-point registers), we need to transform the
+ // copies into subregister copies with other restrictions.
+ struct PPCVSXFMAMutate : public MachineFunctionPass {
+ static char ID;
+ PPCVSXFMAMutate() : MachineFunctionPass(ID) {
+ initializePPCVSXFMAMutatePass(*PassRegistry::getPassRegistry());
+ }
+
+ LiveIntervals *LIS;
+ const PPCInstrInfo *TII;
+
+protected:
+ bool processBlock(MachineBasicBlock &MBB) {
+ bool Changed = false;
+
+ MachineRegisterInfo &MRI = MBB.getParent()->getRegInfo();
+ const TargetRegisterInfo *TRI = &TII->getRegisterInfo();
+ for (MachineBasicBlock::iterator I = MBB.begin(), IE = MBB.end();
+ I != IE; ++I) {
+ MachineInstr *MI = I;
+
+ // The default (A-type) VSX FMA form kills the addend (it is taken from
+ // the target register, which is then updated to reflect the result of
+ // the FMA). If the instruction, however, kills one of the registers
+ // used for the product, then we can use the M-form instruction (which
+ // will take that value from the to-be-defined register).
+
+ int AltOpc = PPC::getAltVSXFMAOpcode(MI->getOpcode());
+ if (AltOpc == -1)
+ continue;
+
+ // This pass is run after register coalescing, and so we're looking for
+ // a situation like this:
+ // ...
+ // %vreg5<def> = COPY %vreg9; VSLRC:%vreg5,%vreg9
+ // %vreg5<def,tied1> = XSMADDADP %vreg5<tied0>, %vreg17, %vreg16,
+ // %RM<imp-use>; VSLRC:%vreg5,%vreg17,%vreg16
+ // ...
+ // %vreg9<def,tied1> = XSMADDADP %vreg9<tied0>, %vreg17, %vreg19,
+ // %RM<imp-use>; VSLRC:%vreg9,%vreg17,%vreg19
+ // ...
+ // Where we can eliminate the copy by changing from the A-type to the
+ // M-type instruction. Specifically, for this example, this means:
+ // %vreg5<def,tied1> = XSMADDADP %vreg5<tied0>, %vreg17, %vreg16,
+ // %RM<imp-use>; VSLRC:%vreg5,%vreg17,%vreg16
+ // is replaced by:
+ // %vreg16<def,tied1> = XSMADDMDP %vreg16<tied0>, %vreg18, %vreg9,
+ // %RM<imp-use>; VSLRC:%vreg16,%vreg18,%vreg9
+ // and we remove: %vreg5<def> = COPY %vreg9; VSLRC:%vreg5,%vreg9
+
+ SlotIndex FMAIdx = LIS->getInstructionIndex(MI);
+
+ VNInfo *AddendValNo =
+ LIS->getInterval(MI->getOperand(1).getReg()).Query(FMAIdx).valueIn();
+ MachineInstr *AddendMI = LIS->getInstructionFromIndex(AddendValNo->def);
+
+ // The addend and this instruction must be in the same block.
+
+ if (!AddendMI || AddendMI->getParent() != MI->getParent())
+ continue;
+
+ // The addend must be a full copy within the same register class.
+
+ if (!AddendMI->isFullCopy())
+ continue;
+
+ unsigned AddendSrcReg = AddendMI->getOperand(1).getReg();
+ if (TargetRegisterInfo::isVirtualRegister(AddendSrcReg)) {
+ if (MRI.getRegClass(AddendMI->getOperand(0).getReg()) !=
+ MRI.getRegClass(AddendSrcReg))
+ continue;
+ } else {
+ // If AddendSrcReg is a physical register, make sure the destination
+ // register class contains it.
+ if (!MRI.getRegClass(AddendMI->getOperand(0).getReg())
+ ->contains(AddendSrcReg))
+ continue;
+ }
+
+ // In theory, there could be other uses of the addend copy before this
+ // fma. We could deal with this, but that would require additional
+ // logic below and I suspect it will not occur in any relevant
+ // situations. Additionally, check whether the copy source is killed
+ // prior to the fma. In order to replace the addend here with the
+ // source of the copy, it must still be live here. We can't use
+ // interval testing for a physical register, so as long as we're
+ // walking the MIs we may as well test liveness here.
+ bool OtherUsers = false, KillsAddendSrc = false;
+ for (auto J = std::prev(I), JE = MachineBasicBlock::iterator(AddendMI);
+ J != JE; --J) {
+ if (J->readsVirtualRegister(AddendMI->getOperand(0).getReg())) {
+ OtherUsers = true;
+ break;
+ }
+ if (J->modifiesRegister(AddendSrcReg, TRI) ||
+ J->killsRegister(AddendSrcReg, TRI)) {
+ KillsAddendSrc = true;
+ break;
+ }
+ }
+
+ if (OtherUsers || KillsAddendSrc)
+ continue;
+
+ // Find one of the product operands that is killed by this instruction.
+
+ unsigned KilledProdOp = 0, OtherProdOp = 0;
+ if (LIS->getInterval(MI->getOperand(2).getReg())
+ .Query(FMAIdx).isKill()) {
+ KilledProdOp = 2;
+ OtherProdOp = 3;
+ } else if (LIS->getInterval(MI->getOperand(3).getReg())
+ .Query(FMAIdx).isKill()) {
+ KilledProdOp = 3;
+ OtherProdOp = 2;
+ }
+
+ // If there are no killed product operands, then this transformation is
+ // likely not profitable.
+ if (!KilledProdOp)
+ continue;
+
+ // For virtual registers, verify that the addend source register
+ // is live here (as should have been assured above).
+ assert((!TargetRegisterInfo::isVirtualRegister(AddendSrcReg) ||
+ LIS->getInterval(AddendSrcReg).liveAt(FMAIdx)) &&
+ "Addend source register is not live!");
+
+ // Transform: (O2 * O3) + O1 -> (O2 * O1) + O3.
+
+ unsigned AddReg = AddendMI->getOperand(1).getReg();
+ unsigned KilledProdReg = MI->getOperand(KilledProdOp).getReg();
+ unsigned OtherProdReg = MI->getOperand(OtherProdOp).getReg();
+
+ unsigned AddSubReg = AddendMI->getOperand(1).getSubReg();
+ unsigned KilledProdSubReg = MI->getOperand(KilledProdOp).getSubReg();
+ unsigned OtherProdSubReg = MI->getOperand(OtherProdOp).getSubReg();
+
+ bool AddRegKill = AddendMI->getOperand(1).isKill();
+ bool KilledProdRegKill = MI->getOperand(KilledProdOp).isKill();
+ bool OtherProdRegKill = MI->getOperand(OtherProdOp).isKill();
+
+ bool AddRegUndef = AddendMI->getOperand(1).isUndef();
+ bool KilledProdRegUndef = MI->getOperand(KilledProdOp).isUndef();
+ bool OtherProdRegUndef = MI->getOperand(OtherProdOp).isUndef();
+
+ unsigned OldFMAReg = MI->getOperand(0).getReg();
+
+ // The transformation doesn't work well with things like:
+ // %vreg5 = A-form-op %vreg5, %vreg11, %vreg5;
+ // so leave such things alone.
+ if (OldFMAReg == KilledProdReg)
+ continue;
+
+ assert(OldFMAReg == AddendMI->getOperand(0).getReg() &&
+ "Addend copy not tied to old FMA output!");
+
+ DEBUG(dbgs() << "VSX FMA Mutation:\n " << *MI;);
+
+ MI->getOperand(0).setReg(KilledProdReg);
+ MI->getOperand(1).setReg(KilledProdReg);
+ MI->getOperand(3).setReg(AddReg);
+ MI->getOperand(2).setReg(OtherProdReg);
+
+ MI->getOperand(0).setSubReg(KilledProdSubReg);
+ MI->getOperand(1).setSubReg(KilledProdSubReg);
+ MI->getOperand(3).setSubReg(AddSubReg);
+ MI->getOperand(2).setSubReg(OtherProdSubReg);
+
+ MI->getOperand(1).setIsKill(KilledProdRegKill);
+ MI->getOperand(3).setIsKill(AddRegKill);
+ MI->getOperand(2).setIsKill(OtherProdRegKill);
+
+ MI->getOperand(1).setIsUndef(KilledProdRegUndef);
+ MI->getOperand(3).setIsUndef(AddRegUndef);
+ MI->getOperand(2).setIsUndef(OtherProdRegUndef);
+
+ MI->setDesc(TII->get(AltOpc));
+
+ DEBUG(dbgs() << " -> " << *MI);
+
+ // The killed product operand was killed here, so we can reuse it now
+ // for the result of the fma.
+
+ LiveInterval &FMAInt = LIS->getInterval(OldFMAReg);
+ VNInfo *FMAValNo = FMAInt.getVNInfoAt(FMAIdx.getRegSlot());
+ for (auto UI = MRI.reg_nodbg_begin(OldFMAReg), UE = MRI.reg_nodbg_end();
+ UI != UE;) {
+ MachineOperand &UseMO = *UI;
+ MachineInstr *UseMI = UseMO.getParent();
+ ++UI;
+
+ // Don't replace the result register of the copy we're about to erase.
+ if (UseMI == AddendMI)
+ continue;
+
+ UseMO.setReg(KilledProdReg);
+ UseMO.setSubReg(KilledProdSubReg);
+ }
+
+ // Extend the live intervals of the killed product operand to hold the
+ // fma result.
+
+ LiveInterval &NewFMAInt = LIS->getInterval(KilledProdReg);
+ for (LiveInterval::iterator AI = FMAInt.begin(), AE = FMAInt.end();
+ AI != AE; ++AI) {
+ // Don't add the segment that corresponds to the original copy.
+ if (AI->valno == AddendValNo)
+ continue;
+
+ VNInfo *NewFMAValNo =
+ NewFMAInt.getNextValue(AI->start,
+ LIS->getVNInfoAllocator());
+
+ NewFMAInt.addSegment(LiveInterval::Segment(AI->start, AI->end,
+ NewFMAValNo));
+ }
+ DEBUG(dbgs() << " extended: " << NewFMAInt << '\n');
+
+ FMAInt.removeValNo(FMAValNo);
+ DEBUG(dbgs() << " trimmed: " << FMAInt << '\n');
+
+ // Remove the (now unused) copy.
+
+ DEBUG(dbgs() << " removing: " << *AddendMI << '\n');
+ LIS->RemoveMachineInstrFromMaps(AddendMI);
+ AddendMI->eraseFromParent();
+
+ Changed = true;
+ }
+
+ return Changed;
+ }
+
+public:
+ bool runOnMachineFunction(MachineFunction &MF) override {
+ // If we don't have VSX then go ahead and return without doing
+ // anything.
+ const PPCSubtarget &STI = MF.getSubtarget<PPCSubtarget>();
+ if (!STI.hasVSX())
+ return false;
+
+ LIS = &getAnalysis<LiveIntervals>();
+
+ TII = STI.getInstrInfo();
+
+ bool Changed = false;
+
+ if (DisableVSXFMAMutate)
+ return Changed;
+
+ for (MachineFunction::iterator I = MF.begin(); I != MF.end();) {
+ MachineBasicBlock &B = *I++;
+ if (processBlock(B))
+ Changed = true;
+ }
+
+ return Changed;
+ }
+
+ void getAnalysisUsage(AnalysisUsage &AU) const override {
+ AU.addRequired<LiveIntervals>();
+ AU.addPreserved<LiveIntervals>();
+ AU.addRequired<SlotIndexes>();
+ AU.addPreserved<SlotIndexes>();
+ MachineFunctionPass::getAnalysisUsage(AU);
+ }
+ };
+}
+
+INITIALIZE_PASS_BEGIN(PPCVSXFMAMutate, DEBUG_TYPE,
+ "PowerPC VSX FMA Mutation", false, false)
+INITIALIZE_PASS_DEPENDENCY(LiveIntervals)
+INITIALIZE_PASS_DEPENDENCY(SlotIndexes)
+INITIALIZE_PASS_END(PPCVSXFMAMutate, DEBUG_TYPE,
+ "PowerPC VSX FMA Mutation", false, false)
+
+char &llvm::PPCVSXFMAMutateID = PPCVSXFMAMutate::ID;
+
+char PPCVSXFMAMutate::ID = 0;
+FunctionPass*
+llvm::createPPCVSXFMAMutatePass() { return new PPCVSXFMAMutate(); }
+
+
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