Index: lib/CodeGen/SelectionDAG/DAGCombiner.cpp =================================================================== --- lib/CodeGen/SelectionDAG/DAGCombiner.cpp +++ lib/CodeGen/SelectionDAG/DAGCombiner.cpp @@ -11230,7 +11230,8 @@ } /// Parses tree in Ptr for base, index, offset addresses. - static BaseIndexOffset match(SDValue Ptr, SelectionDAG &DAG) { + static BaseIndexOffset match(SDValue Ptr, SelectionDAG &DAG, + int64_t PartialOffset = 0) { bool IsIndexSignExt = false; // Split up a folded GlobalAddress+Offset into its component parts. @@ -11239,7 +11240,7 @@ return BaseIndexOffset(DAG.getGlobalAddress(GA->getGlobal(), SDLoc(GA), GA->getValueType(0), - /*Offset=*/0, + /*Offset=*/PartialOffset, /*isTargetGA=*/false, GA->getTargetFlags()), SDValue(), @@ -11251,14 +11252,13 @@ // instruction, then it could be just the BASE or everything else we don't // know how to handle. Just use Ptr as BASE and give up. if (Ptr->getOpcode() != ISD::ADD) - return BaseIndexOffset(Ptr, SDValue(), 0, IsIndexSignExt); + return BaseIndexOffset(Ptr, SDValue(), PartialOffset, IsIndexSignExt); // We know that we have at least an ADD instruction. Try to pattern match // the simple case of BASE + OFFSET. if (isa(Ptr->getOperand(1))) { int64_t Offset = cast(Ptr->getOperand(1))->getSExtValue(); - return BaseIndexOffset(Ptr->getOperand(0), SDValue(), Offset, - IsIndexSignExt); + return match(Ptr->getOperand(0), DAG, Offset + PartialOffset); } // Inside a loop the current BASE pointer is calculated using an ADD and a @@ -11267,7 +11267,7 @@ // (i64 mul (i64 %induction_var) // (i64 %element_size))) if (Ptr->getOperand(1)->getOpcode() == ISD::MUL) - return BaseIndexOffset(Ptr, SDValue(), 0, IsIndexSignExt); + return BaseIndexOffset(Ptr, SDValue(), PartialOffset, IsIndexSignExt); // Look at Base + Index + Offset cases. SDValue Base = Ptr->getOperand(0); @@ -11281,14 +11281,14 @@ // Either the case of Base + Index (no offset) or something else. if (IndexOffset->getOpcode() != ISD::ADD) - return BaseIndexOffset(Base, IndexOffset, 0, IsIndexSignExt); + return BaseIndexOffset(Base, IndexOffset, PartialOffset, IsIndexSignExt); // Now we have the case of Base + Index + offset. SDValue Index = IndexOffset->getOperand(0); SDValue Offset = IndexOffset->getOperand(1); if (!isa(Offset)) - return BaseIndexOffset(Ptr, SDValue(), 0, IsIndexSignExt); + return BaseIndexOffset(Ptr, SDValue(), PartialOffset, IsIndexSignExt); // Ignore signextends. if (Index->getOpcode() == ISD::SIGN_EXTEND) { @@ -11297,7 +11297,7 @@ } else IsIndexSignExt = false; int64_t Off = cast(Offset)->getSExtValue(); - return BaseIndexOffset(Base, Index, Off, IsIndexSignExt); + return BaseIndexOffset(Base, Index, Off + PartialOffset, IsIndexSignExt); } }; } // namespace Index: test/CodeGen/X86/MergeConsecutiveStores.ll =================================================================== --- test/CodeGen/X86/MergeConsecutiveStores.ll +++ test/CodeGen/X86/MergeConsecutiveStores.ll @@ -371,6 +371,40 @@ } ; Make sure that we merge the consecutive load/store sequence below and use a +; word (16 bit) instead of a byte copy for complicated address calculation. +; . +; CHECK-LABEL: MergeLoadStoreBaseIndexOffsetComplicated: +; BWON: movzwl (%{{.*}},%{{.*}}), %e[[REG:[a-z]+]] +; BWOFF: movw (%{{.*}},%{{.*}}), %[[REG:[a-z]+]] +; CHECK: movw %[[REG]], (%{{.*}}) +define void @MergeLoadStoreBaseIndexOffsetComplicated(i8* %a, i8* %b, i8* %c, i64 %n) { + br label %1 + +;