[globalisel] Rename G_GEP to G_PTR_ADD

Summary:
G_GEP is rather poorly named. It's a simple pointer+scalar addition and
doesn't support any of the complexities of getelementptr. I therefore
propose that we rename it. There's a G_PTR_MASK so let's follow that
convention and go with G_PTR_ADD

Reviewers: volkan, aditya_nandakumar, bogner, rovka, arsenm

Subscribers: sdardis, jvesely, wdng, nhaehnle, hiraditya, jrtc27, atanasyan, arphaman, Petar.Avramovic, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69734

8 files changed, 40 insertions, 38 deletions

diff --git a/llvm/lib/CodeGen/GlobalISel/CSEInfo.cpp b/llvm/lib/CodeGen/GlobalISel/CSEInfo.cpp
index 7d9d812d34b..4caabca8328 100644
--- a/llvm/lib/CodeGen/GlobalISel/CSEInfo.cpp
+++ b/llvm/lib/CodeGen/GlobalISel/CSEInfo.cpp
@@ -52,7 +52,7 @@ bool CSEConfigFull::shouldCSEOpc(unsigned Opc) {
   case TargetOpcode::G_ANYEXT:
   case TargetOpcode::G_UNMERGE_VALUES:
   case TargetOpcode::G_TRUNC:
-  case TargetOpcode::G_GEP:
+  case TargetOpcode::G_PTR_ADD:
     return true;
   }
   return false;
diff --git a/llvm/lib/CodeGen/GlobalISel/CombinerHelper.cpp b/llvm/lib/CodeGen/GlobalISel/CombinerHelper.cpp
index bb7f751de90..873378a97c4 100644
--- a/llvm/lib/CodeGen/GlobalISel/CombinerHelper.cpp
+++ b/llvm/lib/CodeGen/GlobalISel/CombinerHelper.cpp
@@ -571,7 +571,7 @@ bool CombinerHelper::findPostIndexCandidate(MachineInstr &MI, Register &Addr,
   LLVM_DEBUG(dbgs() << "Searching for post-indexing opportunity for: " << MI);
 
   for (auto &Use : MRI.use_instructions(Base)) {
-    if (Use.getOpcode() != TargetOpcode::G_GEP)
+    if (Use.getOpcode() != TargetOpcode::G_PTR_ADD)
       continue;
 
     Offset = Use.getOperand(2).getReg();
@@ -597,8 +597,8 @@ bool CombinerHelper::findPostIndexCandidate(MachineInstr &MI, Register &Addr,
     // forming an indexed one.
 
     bool MemOpDominatesAddrUses = true;
-    for (auto &GEPUse : MRI.use_instructions(Use.getOperand(0).getReg())) {
-      if (!dominates(MI, GEPUse)) {
+    for (auto &PtrAddUse : MRI.use_instructions(Use.getOperand(0).getReg())) {
+      if (!dominates(MI, PtrAddUse)) {
         MemOpDominatesAddrUses = false;
         break;
       }
@@ -631,7 +631,7 @@ bool CombinerHelper::findPreIndexCandidate(MachineInstr &MI, Register &Addr,
 #endif
 
   Addr = MI.getOperand(1).getReg();
-  MachineInstr *AddrDef = getOpcodeDef(TargetOpcode::G_GEP, Addr, MRI);
+  MachineInstr *AddrDef = getOpcodeDef(TargetOpcode::G_PTR_ADD, Addr, MRI);
   if (!AddrDef || MRI.hasOneUse(Addr))
     return false;
 
@@ -667,8 +667,8 @@ bool CombinerHelper::findPreIndexCandidate(MachineInstr &MI, Register &Addr,
     }
   }
 
-  // FIXME: check whether all uses of the base pointer are constant GEPs. That
-  // might allow us to end base's liveness here by adjusting the constant.
+  // FIXME: check whether all uses of the base pointer are constant PtrAdds.
+  // That might allow us to end base's liveness here by adjusting the constant.
 
   for (auto &UseMI : MRI.use_instructions(Addr)) {
     if (!dominates(MI, UseMI)) {
@@ -1016,7 +1016,7 @@ bool CombinerHelper::optimizeMemset(MachineInstr &MI, Register Dst, Register Val
     if (DstOff != 0) {
       auto Offset =
           MIB.buildConstant(LLT::scalar(PtrTy.getSizeInBits()), DstOff);
-      Ptr = MIB.buildGEP(PtrTy, Dst, Offset).getReg(0);
+      Ptr = MIB.buildPtrAdd(PtrTy, Dst, Offset).getReg(0);
     }
 
     MIB.buildStore(Value, Ptr, *StoreMMO);
@@ -1121,13 +1121,13 @@ bool CombinerHelper::optimizeMemcpy(MachineInstr &MI, Register Dst,
     if (CurrOffset != 0) {
       Offset = MIB.buildConstant(LLT::scalar(PtrTy.getSizeInBits()), CurrOffset)
                    .getReg(0);
-      LoadPtr = MIB.buildGEP(PtrTy, Src, Offset).getReg(0);
+      LoadPtr = MIB.buildPtrAdd(PtrTy, Src, Offset).getReg(0);
     }
     auto LdVal = MIB.buildLoad(CopyTy, LoadPtr, *LoadMMO);
 
     // Create the store.
     Register StorePtr =
-        CurrOffset == 0 ? Dst : MIB.buildGEP(PtrTy, Dst, Offset).getReg(0);
+        CurrOffset == 0 ? Dst : MIB.buildPtrAdd(PtrTy, Dst, Offset).getReg(0);
     MIB.buildStore(LdVal, StorePtr, *StoreMMO);
     CurrOffset += CopyTy.getSizeInBytes();
     Size -= CopyTy.getSizeInBytes();
@@ -1218,7 +1218,7 @@ bool CombinerHelper::optimizeMemmove(MachineInstr &MI, Register Dst,
     if (CurrOffset != 0) {
       auto Offset =
           MIB.buildConstant(LLT::scalar(PtrTy.getSizeInBits()), CurrOffset);
-      LoadPtr = MIB.buildGEP(PtrTy, Src, Offset).getReg(0);
+      LoadPtr = MIB.buildPtrAdd(PtrTy, Src, Offset).getReg(0);
     }
     LoadVals.push_back(MIB.buildLoad(CopyTy, LoadPtr, *LoadMMO).getReg(0));
     CurrOffset += CopyTy.getSizeInBytes();
@@ -1235,7 +1235,7 @@ bool CombinerHelper::optimizeMemmove(MachineInstr &MI, Register Dst,
     if (CurrOffset != 0) {
       auto Offset =
           MIB.buildConstant(LLT::scalar(PtrTy.getSizeInBits()), CurrOffset);
-      StorePtr = MIB.buildGEP(PtrTy, Dst, Offset).getReg(0);
+      StorePtr = MIB.buildPtrAdd(PtrTy, Dst, Offset).getReg(0);
     }
     MIB.buildStore(LoadVals[I], StorePtr, *StoreMMO);
     CurrOffset += CopyTy.getSizeInBytes();
diff --git a/llvm/lib/CodeGen/GlobalISel/GISelKnownBits.cpp b/llvm/lib/CodeGen/GlobalISel/GISelKnownBits.cpp
index be8efa8795f..41ef631906e 100644
--- a/llvm/lib/CodeGen/GlobalISel/GISelKnownBits.cpp
+++ b/llvm/lib/CodeGen/GlobalISel/GISelKnownBits.cpp
@@ -179,8 +179,8 @@ void GISelKnownBits::computeKnownBitsImpl(Register R, KnownBits &Known,
     Known.Zero = KnownZeroOut;
     break;
   }
-  case TargetOpcode::G_GEP: {
-    // G_GEP is like G_ADD. FIXME: Is this true for all targets?
+  case TargetOpcode::G_PTR_ADD: {
+    // G_PTR_ADD is like G_ADD. FIXME: Is this true for all targets?
     LLT Ty = MRI.getType(MI.getOperand(1).getReg());
     if (DL.isNonIntegralAddressSpace(Ty.getAddressSpace()))
       break;
diff --git a/llvm/lib/CodeGen/GlobalISel/IRTranslator.cpp b/llvm/lib/CodeGen/GlobalISel/IRTranslator.cpp
index e712812abd1..2080a381e51 100644
--- a/llvm/lib/CodeGen/GlobalISel/IRTranslator.cpp
+++ b/llvm/lib/CodeGen/GlobalISel/IRTranslator.cpp
@@ -885,7 +885,7 @@ bool IRTranslator::translateLoad(const User &U, MachineIRBuilder &MIRBuilder) {
       Regs.size() == 1 ? LI.getMetadata(LLVMContext::MD_range) : nullptr;
   for (unsigned i = 0; i < Regs.size(); ++i) {
     Register Addr;
-    MIRBuilder.materializeGEP(Addr, Base, OffsetTy, Offsets[i] / 8);
+    MIRBuilder.materializePtrAdd(Addr, Base, OffsetTy, Offsets[i] / 8);
 
     MachinePointerInfo Ptr(LI.getPointerOperand(), Offsets[i] / 8);
     unsigned BaseAlign = getMemOpAlignment(LI);
@@ -926,7 +926,7 @@ bool IRTranslator::translateStore(const User &U, MachineIRBuilder &MIRBuilder) {
 
   for (unsigned i = 0; i < Vals.size(); ++i) {
     Register Addr;
-    MIRBuilder.materializeGEP(Addr, Base, OffsetTy, Offsets[i] / 8);
+    MIRBuilder.materializePtrAdd(Addr, Base, OffsetTy, Offsets[i] / 8);
 
     MachinePointerInfo Ptr(SI.getPointerOperand(), Offsets[i] / 8);
     unsigned BaseAlign = getMemOpAlignment(SI);
@@ -1080,8 +1080,8 @@ bool IRTranslator::translateGetElementPtr(const User &U,
       if (Offset != 0) {
         LLT OffsetTy = getLLTForType(*OffsetIRTy, *DL);
         auto OffsetMIB = MIRBuilder.buildConstant({OffsetTy}, Offset);
-        BaseReg =
-            MIRBuilder.buildGEP(PtrTy, BaseReg, OffsetMIB.getReg(0)).getReg(0);
+        BaseReg = MIRBuilder.buildPtrAdd(PtrTy, BaseReg, OffsetMIB.getReg(0))
+                      .getReg(0);
         Offset = 0;
       }
 
@@ -1100,14 +1100,14 @@ bool IRTranslator::translateGetElementPtr(const User &U,
       } else
         GepOffsetReg = IdxReg;
 
-      BaseReg = MIRBuilder.buildGEP(PtrTy, BaseReg, GepOffsetReg).getReg(0);
+      BaseReg = MIRBuilder.buildPtrAdd(PtrTy, BaseReg, GepOffsetReg).getReg(0);
     }
   }
 
   if (Offset != 0) {
     auto OffsetMIB =
         MIRBuilder.buildConstant(getLLTForType(*OffsetIRTy, *DL), Offset);
-    MIRBuilder.buildGEP(getOrCreateVReg(U), BaseReg, OffsetMIB.getReg(0));
+    MIRBuilder.buildPtrAdd(getOrCreateVReg(U), BaseReg, OffsetMIB.getReg(0));
     return true;
   }
 
diff --git a/llvm/lib/CodeGen/GlobalISel/InstructionSelector.cpp b/llvm/lib/CodeGen/GlobalISel/InstructionSelector.cpp
index 28143b30d4e..b9c90e69ddb 100644
--- a/llvm/lib/CodeGen/GlobalISel/InstructionSelector.cpp
+++ b/llvm/lib/CodeGen/GlobalISel/InstructionSelector.cpp
@@ -60,7 +60,7 @@ bool InstructionSelector::isBaseWithConstantOffset(
     return false;
 
   MachineInstr *RootI = MRI.getVRegDef(Root.getReg());
-  if (RootI->getOpcode() != TargetOpcode::G_GEP)
+  if (RootI->getOpcode() != TargetOpcode::G_PTR_ADD)
     return false;
 
   MachineOperand &RHS = RootI->getOperand(2);
diff --git a/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp b/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
index 761dd0a5487..a85e04e04a1 100644
--- a/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
+++ b/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
@@ -1748,8 +1748,8 @@ LegalizerHelper::widenScalar(MachineInstr &MI, unsigned TypeIdx, LLT WideTy) {
     Observer.changedInstr(MI);
     return Legalized;
 
-  case TargetOpcode::G_GEP:
-    assert(TypeIdx == 1 && "unable to legalize pointer of GEP");
+  case TargetOpcode::G_PTR_ADD:
+    assert(TypeIdx == 1 && "unable to legalize pointer of G_PTR_ADD");
     Observer.changingInstr(MI);
     widenScalarSrc(MI, WideTy, 2, TargetOpcode::G_SEXT);
     Observer.changedInstr(MI);
@@ -2083,8 +2083,9 @@ LegalizerHelper::lower(MachineInstr &MI, unsigned TypeIdx, LLT Ty) {
 
         auto OffsetCst =
             MIRBuilder.buildConstant(LLT::scalar(64), LargeSplitSize / 8);
-        Register GEPReg = MRI.createGenericVirtualRegister(PtrTy);
-        auto SmallPtr = MIRBuilder.buildGEP(GEPReg, PtrReg, OffsetCst.getReg(0));
+        Register PtrAddReg = MRI.createGenericVirtualRegister(PtrTy);
+        auto SmallPtr =
+            MIRBuilder.buildPtrAdd(PtrAddReg, PtrReg, OffsetCst.getReg(0));
         auto SmallLoad = MIRBuilder.buildLoad(SmallLdReg, SmallPtr.getReg(0),
                                               *SmallMMO);
 
@@ -2151,12 +2152,13 @@ LegalizerHelper::lower(MachineInstr &MI, unsigned TypeIdx, LLT Ty) {
     auto ShiftAmt = MIRBuilder.buildConstant(ExtendTy, LargeSplitSize);
     auto SmallVal = MIRBuilder.buildLShr(ExtendTy, ExtVal, ShiftAmt);
 
-    // Generate the GEP and truncating stores.
+    // Generate the PtrAdd and truncating stores.
     LLT PtrTy = MRI.getType(PtrReg);
     auto OffsetCst =
         MIRBuilder.buildConstant(LLT::scalar(64), LargeSplitSize / 8);
-    Register GEPReg = MRI.createGenericVirtualRegister(PtrTy);
-    auto SmallPtr = MIRBuilder.buildGEP(GEPReg, PtrReg, OffsetCst.getReg(0));
+    Register PtrAddReg = MRI.createGenericVirtualRegister(PtrTy);
+    auto SmallPtr =
+        MIRBuilder.buildPtrAdd(PtrAddReg, PtrReg, OffsetCst.getReg(0));
 
     MachineFunction &MF = MIRBuilder.getMF();
     MachineMemOperand *LargeMMO =
@@ -2908,7 +2910,7 @@ LegalizerHelper::reduceLoadStoreWidth(MachineInstr &MI, unsigned TypeIdx,
       unsigned ByteOffset = Offset / 8;
       Register NewAddrReg;
 
-      MIRBuilder.materializeGEP(NewAddrReg, AddrReg, OffsetTy, ByteOffset);
+      MIRBuilder.materializePtrAdd(NewAddrReg, AddrReg, OffsetTy, ByteOffset);
 
       MachineMemOperand *NewMMO =
         MF.getMachineMemOperand(MMO, ByteOffset, ByteSize);
@@ -4176,7 +4178,7 @@ LegalizerHelper::lowerDynStackAlloc(MachineInstr &MI) {
 
   // Subtract the final alloc from the SP. We use G_PTRTOINT here so we don't
   // have to generate an extra instruction to negate the alloc and then use
-  // G_GEP to add the negative offset.
+  // G_PTR_ADD to add the negative offset.
   auto Alloc = MIRBuilder.buildSub(IntPtrTy, SPTmp, AllocSize);
   if (Align) {
     APInt AlignMask(IntPtrTy.getSizeInBits(), Align, true);
diff --git a/llvm/lib/CodeGen/GlobalISel/MachineIRBuilder.cpp b/llvm/lib/CodeGen/GlobalISel/MachineIRBuilder.cpp
index 1c5b6fc3ed8..67d9dacda61 100644
--- a/llvm/lib/CodeGen/GlobalISel/MachineIRBuilder.cpp
+++ b/llvm/lib/CodeGen/GlobalISel/MachineIRBuilder.cpp
@@ -219,19 +219,19 @@ void MachineIRBuilder::validateShiftOp(const LLT &Res, const LLT &Op0,
   assert((Res == Op0) && "type mismatch");
 }
 
-MachineInstrBuilder MachineIRBuilder::buildGEP(const DstOp &Res,
-                                               const SrcOp &Op0,
-                                               const SrcOp &Op1) {
+MachineInstrBuilder MachineIRBuilder::buildPtrAdd(const DstOp &Res,
+                                                  const SrcOp &Op0,
+                                                  const SrcOp &Op1) {
   assert(Res.getLLTTy(*getMRI()).isPointer() &&
          Res.getLLTTy(*getMRI()) == Op0.getLLTTy(*getMRI()) && "type mismatch");
   assert(Op1.getLLTTy(*getMRI()).isScalar() && "invalid offset type");
 
-  return buildInstr(TargetOpcode::G_GEP, {Res}, {Op0, Op1});
+  return buildInstr(TargetOpcode::G_PTR_ADD, {Res}, {Op0, Op1});
 }
 
 Optional<MachineInstrBuilder>
-MachineIRBuilder::materializeGEP(Register &Res, Register Op0,
-                                 const LLT &ValueTy, uint64_t Value) {
+MachineIRBuilder::materializePtrAdd(Register &Res, Register Op0,
+                                    const LLT &ValueTy, uint64_t Value) {
   assert(Res == 0 && "Res is a result argument");
   assert(ValueTy.isScalar()  && "invalid offset type");
 
@@ -242,7 +242,7 @@ MachineIRBuilder::materializeGEP(Register &Res, Register Op0,
 
   Res = getMRI()->createGenericVirtualRegister(getMRI()->getType(Op0));
   auto Cst = buildConstant(ValueTy, Value);
-  return buildGEP(Res, Op0, Cst.getReg(0));
+  return buildPtrAdd(Res, Op0, Cst.getReg(0));
 }
 
 MachineInstrBuilder MachineIRBuilder::buildPtrMask(const DstOp &Res,
diff --git a/llvm/lib/CodeGen/MachineVerifier.cpp b/llvm/lib/CodeGen/MachineVerifier.cpp
index b5dea283185..6361a49d962 100644
--- a/llvm/lib/CodeGen/MachineVerifier.cpp
+++ b/llvm/lib/CodeGen/MachineVerifier.cpp
@@ -1100,7 +1100,7 @@ void MachineVerifier::verifyPreISelGenericInstruction(const MachineInstr *MI) {
 
     break;
   }
-  case TargetOpcode::G_GEP: {
+  case TargetOpcode::G_PTR_ADD: {
     LLT DstTy = MRI->getType(MI->getOperand(0).getReg());
     LLT PtrTy = MRI->getType(MI->getOperand(1).getReg());
     LLT OffsetTy = MRI->getType(MI->getOperand(2).getReg());