Index: lib/CodeGen/GlobalISel/IRTranslator.cpp =================================================================== --- lib/CodeGen/GlobalISel/IRTranslator.cpp +++ lib/CodeGen/GlobalISel/IRTranslator.cpp @@ -340,6 +340,15 @@ Type *Int32Ty = Type::getInt32Ty(U.getContext()); SmallVector Indices; + // If Src is a single element ConstantStruct, translate extractvalue + // to that element to avoid inserting a cast instruction. + if (auto CS = dyn_cast(Src)) + if (CS->getNumOperands() == 1) { + unsigned Res = getOrCreateVReg(*CS->getOperand(0)); + ValToVReg[&U] = Res; + return true; + } + // 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)); @@ -1108,6 +1117,23 @@ default: return false; } + } else if (auto CS = dyn_cast(&C)) { + // Return the element if it is a single element ConstantStruct. + if (CS->getNumOperands() == 1) { + unsigned EltReg = getOrCreateVReg(*CS->getOperand(0)); + EntryBuilder.buildCast(Reg, EltReg); + return true; + } + std::vector Ops; + std::vector Indices; + uint64_t Offset = 0; + for (unsigned i = 0; i < CS->getNumOperands(); ++i) { + unsigned OpReg = getOrCreateVReg(*CS->getOperand(i)); + Ops.push_back(OpReg); + Indices.push_back(Offset); + Offset += MRI->getType(OpReg).getSizeInBits(); + } + EntryBuilder.buildSequence(Reg, Ops, Indices); } else if (auto CV = dyn_cast(&C)) { if (CV->getNumOperands() == 1) return translate(*CV->getOperand(0), Reg); Index: test/CodeGen/ARM/GlobalISel/arm-irtranslator.ll =================================================================== --- test/CodeGen/ARM/GlobalISel/arm-irtranslator.ll +++ test/CodeGen/ARM/GlobalISel/arm-irtranslator.ll @@ -699,3 +699,33 @@ %res = extractelement <2 x i32> %shuffle, i32 0 ret i32 %res } + +%struct.v2s32 = type { <2 x i32> } + +define i32 @test_constantstruct_v2s32() { +; CHECK-LABEL: name: test_constantstruct_v2s32 +; CHECK: [[C1:%[0-9]+]](s32) = G_CONSTANT i32 1 +; CHECK: [[C2:%[0-9]+]](s32) = G_CONSTANT i32 2 +; CHECK: [[VEC:%[0-9]+]](<2 x s32>) = G_MERGE_VALUES [[C1]](s32), [[C2]](s32) +; CHECK: G_EXTRACT_VECTOR_ELT [[VEC]](<2 x s32>) + %vec = extractvalue %struct.v2s32 {<2 x i32>}, 0 + %elt = extractelement <2 x i32> %vec, i32 0 + ret i32 %elt +} + +%struct.v2s32.s32.s32 = type { <2 x i32>, i32, i32 } + +define i32 @test_constantstruct_v2s32_s32_s32() { +; CHECK-LABEL: name: test_constantstruct_v2s32_s32_s32 +; CHECK: [[C1:%[0-9]+]](s32) = G_CONSTANT i32 1 +; CHECK: [[C2:%[0-9]+]](s32) = G_CONSTANT i32 2 +; CHECK: [[VEC:%[0-9]+]](<2 x s32>) = G_MERGE_VALUES [[C1]](s32), [[C2]](s32) +; CHECK: [[C3:%[0-9]+]](s32) = G_CONSTANT i32 3 +; CHECK: [[C4:%[0-9]+]](s32) = G_CONSTANT i32 4 +; CHECK: [[CS:%[0-9]+]](s128) = G_SEQUENCE [[VEC]](<2 x s32>), 0, [[C3]](s32), 64, [[C4]](s32), 96 +; CHECK: [[EXT:%[0-9]+]](<2 x s32>) = G_EXTRACT [[CS]](s128), 0 +; CHECK: G_EXTRACT_VECTOR_ELT [[EXT]](<2 x s32>) + %vec = extractvalue %struct.v2s32.s32.s32 {<2 x i32>, i32 3, i32 4}, 0 + %elt = extractelement <2 x i32> %vec, i32 0 + ret i32 %elt +}