GlobalISel: support translation of extractvalue instructions.

llvm-svn: 279285

llvm/include/llvm/CodeGen/GlobalISel/IRTranslator.h

@@ -149,6 +149,8 @@ private:
   /// \pre \p U is a branch instruction.
   bool translateBr(const User &U);
 
+  bool translateExtractValue(const User &U);
+
   /// Translate return (ret) instruction.
   /// The target needs to implement CallLowering::lowerReturn for
   /// this to succeed.
@@ -266,7 +268,6 @@ private:
   bool translateExtractElement(const User &U) { return false; }
   bool translateInsertElement(const User &U) { return false; }
   bool translateShuffleVector(const User &U) { return false; }
-  bool translateExtractValue(const User &U) { return false; }
   bool translateInsertValue(const User &U) { return false; }
   bool translateLandingPad(const User &U) { return false; }
 

llvm/include/llvm/CodeGen/GlobalISel/MachineIRBuilder.h

@@ -225,7 +225,7 @@ public:
   ///
   /// \return a MachineInstrBuilder for the newly created instruction.
   MachineInstrBuilder buildExtract(LLT Ty, ArrayRef<unsigned> Results,
-                                   unsigned Src, ArrayRef<unsigned> Indexes);
+                                   unsigned Src, ArrayRef<uint64_t> Indexes);
 
   /// Build and insert \p Res<def> = G_SEQUENCE \p Ty \p Op0, \p Idx0...
   ///

llvm/lib/CodeGen/GlobalISel/IRTranslator.cpp

@@ -182,6 +182,27 @@ bool IRTranslator::translateStore(const User &U) {
   return true;
 }
 
+bool IRTranslator::translateExtractValue(const User &U) {
+  const ExtractValueInst &EVI = cast<ExtractValueInst>(U);
+  const Value *Src = EVI.getAggregateOperand();
+  Type *Int32Ty = Type::getInt32Ty(EVI.getContext());
+  SmallVector<Value *, 1> Indices;
+
+  // getIndexedOffsetInType is designed for GEPs, so the first index is the
+  // usual array element rather than looking into the actual aggregate.
+  Indices.push_back(ConstantInt::get(Int32Ty, 0));
+  for (auto Idx : EVI.indices())
+    Indices.push_back(ConstantInt::get(Int32Ty, Idx));
+
+  uint64_t Offset = 8 * DL->getIndexedOffsetInType(Src->getType(), Indices);
+
+  unsigned Res = getOrCreateVReg(EVI);
+  MIRBuilder.buildExtract(LLT{*EVI.getType()}, Res, getOrCreateVReg(*Src),
+                          Offset);
+
+  return true;
+}
+
 bool IRTranslator::translateBitCast(const User &U) {
   if (LLT{*U.getOperand(0)->getType()} == LLT{*U.getType()}) {
     unsigned &Reg = ValToVReg[&U];

llvm/lib/CodeGen/GlobalISel/MachineIRBuilder.cpp

@@ -143,7 +143,7 @@ MachineInstrBuilder MachineIRBuilder::buildAnyExtend(LLT Ty, unsigned Res,
 
 MachineInstrBuilder
 MachineIRBuilder::buildExtract(LLT Ty, ArrayRef<unsigned> Results, unsigned Src,
-                               ArrayRef<unsigned> Indexes) {
+                               ArrayRef<uint64_t> Indexes) {
   assert(Results.size() == Indexes.size() && "inconsistent number of regs");
 
   MachineInstrBuilder MIB = buildInstr(TargetOpcode::G_EXTRACT, Ty);

llvm/lib/CodeGen/GlobalISel/MachineLegalizeHelper.cpp

@@ -51,7 +51,7 @@ MachineLegalizeHelper::LegalizeResult MachineLegalizeHelper::legalizeInstr(
 void MachineLegalizeHelper::extractParts(unsigned Reg, LLT Ty, int NumParts,
                                          SmallVectorImpl<unsigned> &VRegs) {
   unsigned Size = Ty.getSizeInBits();
-  SmallVector<unsigned, 4> Indexes;
+  SmallVector<uint64_t, 4> Indexes;
   for (int i = 0; i < NumParts; ++i) {
     VRegs.push_back(MRI.createGenericVirtualRegister(Size));
     Indexes.push_back(i * Size);

llvm/test/CodeGen/AArch64/GlobalISel/arm64-irtranslator.ll

@@ -682,3 +682,14 @@ define void @test_umul_overflow(i32 %lhs, i32 %rhs, { i32, i1 }* %addr) {
   store { i32, i1 } %res, { i32, i1 }* %addr
   ret void
 }
+
+; CHECK-LABEL: name: test_extractvalue
+; CHECK: [[STRUCT:%[0-9]+]](128) = G_LOAD { s128, p0 }
+; CHECK: [[RES:%[0-9]+]](32) = G_EXTRACT s32 [[STRUCT]], 64
+; CHECK: %w0 = COPY [[RES]]
+%struct.nested = type {i8, { i8, i32 }, i32}
+define i32 @test_extractvalue(%struct.nested* %addr) {
+  %struct = load %struct.nested, %struct.nested* %addr
+  %res = extractvalue %struct.nested %struct, 1, 1
+  ret i32 %res
+}