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Extend r186072 to handle shifts and ANDs. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186073 91177308-0d34-0410-b5e6-96231b3b80d8
841 lines
30 KiB
C++
841 lines
30 KiB
C++
//===-- SystemZISelDAGToDAG.cpp - A dag to dag inst selector for SystemZ --===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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//
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// This file defines an instruction selector for the SystemZ target.
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//
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//===----------------------------------------------------------------------===//
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#include "SystemZTargetMachine.h"
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#include "llvm/Analysis/AliasAnalysis.h"
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#include "llvm/CodeGen/SelectionDAGISel.h"
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#include "llvm/Support/Debug.h"
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#include "llvm/Support/raw_ostream.h"
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using namespace llvm;
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namespace {
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// Used to build addressing modes.
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struct SystemZAddressingMode {
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// The shape of the address.
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enum AddrForm {
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// base+displacement
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FormBD,
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// base+displacement+index for load and store operands
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FormBDXNormal,
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// base+displacement+index for load address operands
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FormBDXLA,
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// base+displacement+index+ADJDYNALLOC
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FormBDXDynAlloc
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};
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AddrForm Form;
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// The type of displacement. The enum names here correspond directly
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// to the definitions in SystemZOperand.td. We could split them into
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// flags -- single/pair, 128-bit, etc. -- but it hardly seems worth it.
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enum DispRange {
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Disp12Only,
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Disp12Pair,
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Disp20Only,
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Disp20Only128,
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Disp20Pair
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};
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DispRange DR;
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// The parts of the address. The address is equivalent to:
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//
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// Base + Disp + Index + (IncludesDynAlloc ? ADJDYNALLOC : 0)
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SDValue Base;
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int64_t Disp;
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SDValue Index;
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bool IncludesDynAlloc;
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SystemZAddressingMode(AddrForm form, DispRange dr)
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: Form(form), DR(dr), Base(), Disp(0), Index(),
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IncludesDynAlloc(false) {}
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// True if the address can have an index register.
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bool hasIndexField() { return Form != FormBD; }
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// True if the address can (and must) include ADJDYNALLOC.
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bool isDynAlloc() { return Form == FormBDXDynAlloc; }
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void dump() {
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errs() << "SystemZAddressingMode " << this << '\n';
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errs() << " Base ";
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if (Base.getNode() != 0)
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Base.getNode()->dump();
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else
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errs() << "null\n";
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if (hasIndexField()) {
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errs() << " Index ";
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if (Index.getNode() != 0)
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Index.getNode()->dump();
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else
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errs() << "null\n";
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}
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errs() << " Disp " << Disp;
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if (IncludesDynAlloc)
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errs() << " + ADJDYNALLOC";
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errs() << '\n';
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}
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};
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class SystemZDAGToDAGISel : public SelectionDAGISel {
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const SystemZTargetLowering &Lowering;
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const SystemZSubtarget &Subtarget;
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// Used by SystemZOperands.td to create integer constants.
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inline SDValue getImm(const SDNode *Node, uint64_t Imm) {
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return CurDAG->getTargetConstant(Imm, Node->getValueType(0));
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}
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// Try to fold more of the base or index of AM into AM, where IsBase
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// selects between the base and index.
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bool expandAddress(SystemZAddressingMode &AM, bool IsBase);
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// Try to describe N in AM, returning true on success.
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bool selectAddress(SDValue N, SystemZAddressingMode &AM);
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// Extract individual target operands from matched address AM.
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void getAddressOperands(const SystemZAddressingMode &AM, EVT VT,
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SDValue &Base, SDValue &Disp);
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void getAddressOperands(const SystemZAddressingMode &AM, EVT VT,
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SDValue &Base, SDValue &Disp, SDValue &Index);
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// Try to match Addr as a FormBD address with displacement type DR.
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// Return true on success, storing the base and displacement in
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// Base and Disp respectively.
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bool selectBDAddr(SystemZAddressingMode::DispRange DR, SDValue Addr,
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SDValue &Base, SDValue &Disp);
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// Try to match Addr as a FormBDX* address of form Form with
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// displacement type DR. Return true on success, storing the base,
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// displacement and index in Base, Disp and Index respectively.
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bool selectBDXAddr(SystemZAddressingMode::AddrForm Form,
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SystemZAddressingMode::DispRange DR, SDValue Addr,
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SDValue &Base, SDValue &Disp, SDValue &Index);
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// PC-relative address matching routines used by SystemZOperands.td.
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bool selectPCRelAddress(SDValue Addr, SDValue &Target) {
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if (Addr.getOpcode() == SystemZISD::PCREL_WRAPPER) {
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Target = Addr.getOperand(0);
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return true;
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}
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return false;
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}
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// BD matching routines used by SystemZOperands.td.
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bool selectBDAddr12Only(SDValue Addr, SDValue &Base, SDValue &Disp) {
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return selectBDAddr(SystemZAddressingMode::Disp12Only, Addr, Base, Disp);
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}
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bool selectBDAddr12Pair(SDValue Addr, SDValue &Base, SDValue &Disp) {
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return selectBDAddr(SystemZAddressingMode::Disp12Pair, Addr, Base, Disp);
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}
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bool selectBDAddr20Only(SDValue Addr, SDValue &Base, SDValue &Disp) {
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return selectBDAddr(SystemZAddressingMode::Disp20Only, Addr, Base, Disp);
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}
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bool selectBDAddr20Pair(SDValue Addr, SDValue &Base, SDValue &Disp) {
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return selectBDAddr(SystemZAddressingMode::Disp20Pair, Addr, Base, Disp);
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}
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// BDX matching routines used by SystemZOperands.td.
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bool selectBDXAddr12Only(SDValue Addr, SDValue &Base, SDValue &Disp,
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SDValue &Index) {
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return selectBDXAddr(SystemZAddressingMode::FormBDXNormal,
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SystemZAddressingMode::Disp12Only,
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Addr, Base, Disp, Index);
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}
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bool selectBDXAddr12Pair(SDValue Addr, SDValue &Base, SDValue &Disp,
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SDValue &Index) {
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return selectBDXAddr(SystemZAddressingMode::FormBDXNormal,
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SystemZAddressingMode::Disp12Pair,
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Addr, Base, Disp, Index);
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}
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bool selectDynAlloc12Only(SDValue Addr, SDValue &Base, SDValue &Disp,
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SDValue &Index) {
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return selectBDXAddr(SystemZAddressingMode::FormBDXDynAlloc,
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SystemZAddressingMode::Disp12Only,
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Addr, Base, Disp, Index);
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}
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bool selectBDXAddr20Only(SDValue Addr, SDValue &Base, SDValue &Disp,
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SDValue &Index) {
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return selectBDXAddr(SystemZAddressingMode::FormBDXNormal,
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SystemZAddressingMode::Disp20Only,
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Addr, Base, Disp, Index);
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}
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bool selectBDXAddr20Only128(SDValue Addr, SDValue &Base, SDValue &Disp,
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SDValue &Index) {
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return selectBDXAddr(SystemZAddressingMode::FormBDXNormal,
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SystemZAddressingMode::Disp20Only128,
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Addr, Base, Disp, Index);
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}
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bool selectBDXAddr20Pair(SDValue Addr, SDValue &Base, SDValue &Disp,
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SDValue &Index) {
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return selectBDXAddr(SystemZAddressingMode::FormBDXNormal,
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SystemZAddressingMode::Disp20Pair,
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Addr, Base, Disp, Index);
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}
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bool selectLAAddr12Pair(SDValue Addr, SDValue &Base, SDValue &Disp,
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SDValue &Index) {
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return selectBDXAddr(SystemZAddressingMode::FormBDXLA,
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SystemZAddressingMode::Disp12Pair,
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Addr, Base, Disp, Index);
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}
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bool selectLAAddr20Pair(SDValue Addr, SDValue &Base, SDValue &Disp,
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SDValue &Index) {
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return selectBDXAddr(SystemZAddressingMode::FormBDXLA,
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SystemZAddressingMode::Disp20Pair,
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Addr, Base, Disp, Index);
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}
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// Return an undefined i64 value.
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SDValue getUNDEF64(SDLoc DL);
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// Convert N to VT, if it isn't already.
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SDValue convertTo(SDLoc DL, EVT VT, SDValue N);
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// Try to use RISBG to implement ISD::AND node N. Return the selected
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// node on success, otherwise return null.
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SDNode *tryRISBGForAND(SDNode *N);
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// If Op0 is null, then Node is a constant that can be loaded using:
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//
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// (Opcode UpperVal LowerVal)
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//
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// If Op0 is nonnull, then Node can be implemented using:
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//
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// (Opcode (Opcode Op0 UpperVal) LowerVal)
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SDNode *splitLargeImmediate(unsigned Opcode, SDNode *Node, SDValue Op0,
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uint64_t UpperVal, uint64_t LowerVal);
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bool storeLoadCanUseMVC(SDNode *N) const;
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public:
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SystemZDAGToDAGISel(SystemZTargetMachine &TM, CodeGenOpt::Level OptLevel)
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: SelectionDAGISel(TM, OptLevel),
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Lowering(*TM.getTargetLowering()),
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Subtarget(*TM.getSubtargetImpl()) { }
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// Override MachineFunctionPass.
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virtual const char *getPassName() const LLVM_OVERRIDE {
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return "SystemZ DAG->DAG Pattern Instruction Selection";
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}
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// Override SelectionDAGISel.
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virtual SDNode *Select(SDNode *Node) LLVM_OVERRIDE;
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virtual bool SelectInlineAsmMemoryOperand(const SDValue &Op,
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char ConstraintCode,
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std::vector<SDValue> &OutOps)
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LLVM_OVERRIDE;
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// Include the pieces autogenerated from the target description.
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#include "SystemZGenDAGISel.inc"
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};
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} // end anonymous namespace
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FunctionPass *llvm::createSystemZISelDag(SystemZTargetMachine &TM,
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CodeGenOpt::Level OptLevel) {
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return new SystemZDAGToDAGISel(TM, OptLevel);
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}
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// Return true if Val should be selected as a displacement for an address
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// with range DR. Here we're interested in the range of both the instruction
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// described by DR and of any pairing instruction.
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static bool selectDisp(SystemZAddressingMode::DispRange DR, int64_t Val) {
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switch (DR) {
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case SystemZAddressingMode::Disp12Only:
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return isUInt<12>(Val);
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case SystemZAddressingMode::Disp12Pair:
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case SystemZAddressingMode::Disp20Only:
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case SystemZAddressingMode::Disp20Pair:
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return isInt<20>(Val);
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case SystemZAddressingMode::Disp20Only128:
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return isInt<20>(Val) && isInt<20>(Val + 8);
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}
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llvm_unreachable("Unhandled displacement range");
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}
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// Change the base or index in AM to Value, where IsBase selects
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// between the base and index.
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static void changeComponent(SystemZAddressingMode &AM, bool IsBase,
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SDValue Value) {
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if (IsBase)
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AM.Base = Value;
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else
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AM.Index = Value;
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}
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// The base or index of AM is equivalent to Value + ADJDYNALLOC,
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// where IsBase selects between the base and index. Try to fold the
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// ADJDYNALLOC into AM.
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static bool expandAdjDynAlloc(SystemZAddressingMode &AM, bool IsBase,
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SDValue Value) {
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if (AM.isDynAlloc() && !AM.IncludesDynAlloc) {
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changeComponent(AM, IsBase, Value);
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AM.IncludesDynAlloc = true;
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return true;
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}
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return false;
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}
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// The base of AM is equivalent to Base + Index. Try to use Index as
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// the index register.
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static bool expandIndex(SystemZAddressingMode &AM, SDValue Base,
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SDValue Index) {
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if (AM.hasIndexField() && !AM.Index.getNode()) {
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AM.Base = Base;
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AM.Index = Index;
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return true;
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}
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return false;
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}
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// The base or index of AM is equivalent to Op0 + Op1, where IsBase selects
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// between the base and index. Try to fold Op1 into AM's displacement.
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static bool expandDisp(SystemZAddressingMode &AM, bool IsBase,
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SDValue Op0, ConstantSDNode *Op1) {
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// First try adjusting the displacement.
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int64_t TestDisp = AM.Disp + Op1->getSExtValue();
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if (selectDisp(AM.DR, TestDisp)) {
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changeComponent(AM, IsBase, Op0);
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AM.Disp = TestDisp;
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return true;
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}
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// We could consider forcing the displacement into a register and
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// using it as an index, but it would need to be carefully tuned.
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return false;
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}
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bool SystemZDAGToDAGISel::expandAddress(SystemZAddressingMode &AM,
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bool IsBase) {
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SDValue N = IsBase ? AM.Base : AM.Index;
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unsigned Opcode = N.getOpcode();
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if (Opcode == ISD::TRUNCATE) {
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N = N.getOperand(0);
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Opcode = N.getOpcode();
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}
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if (Opcode == ISD::ADD || CurDAG->isBaseWithConstantOffset(N)) {
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SDValue Op0 = N.getOperand(0);
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SDValue Op1 = N.getOperand(1);
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unsigned Op0Code = Op0->getOpcode();
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unsigned Op1Code = Op1->getOpcode();
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if (Op0Code == SystemZISD::ADJDYNALLOC)
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return expandAdjDynAlloc(AM, IsBase, Op1);
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if (Op1Code == SystemZISD::ADJDYNALLOC)
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return expandAdjDynAlloc(AM, IsBase, Op0);
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if (Op0Code == ISD::Constant)
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return expandDisp(AM, IsBase, Op1, cast<ConstantSDNode>(Op0));
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if (Op1Code == ISD::Constant)
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return expandDisp(AM, IsBase, Op0, cast<ConstantSDNode>(Op1));
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if (IsBase && expandIndex(AM, Op0, Op1))
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return true;
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}
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return false;
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}
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// Return true if an instruction with displacement range DR should be
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// used for displacement value Val. selectDisp(DR, Val) must already hold.
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static bool isValidDisp(SystemZAddressingMode::DispRange DR, int64_t Val) {
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assert(selectDisp(DR, Val) && "Invalid displacement");
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switch (DR) {
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case SystemZAddressingMode::Disp12Only:
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case SystemZAddressingMode::Disp20Only:
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case SystemZAddressingMode::Disp20Only128:
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return true;
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case SystemZAddressingMode::Disp12Pair:
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// Use the other instruction if the displacement is too large.
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return isUInt<12>(Val);
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case SystemZAddressingMode::Disp20Pair:
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// Use the other instruction if the displacement is small enough.
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return !isUInt<12>(Val);
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}
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llvm_unreachable("Unhandled displacement range");
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}
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// Return true if Base + Disp + Index should be performed by LA(Y).
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static bool shouldUseLA(SDNode *Base, int64_t Disp, SDNode *Index) {
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// Don't use LA(Y) for constants.
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if (!Base)
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return false;
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// Always use LA(Y) for frame addresses, since we know that the destination
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// register is almost always (perhaps always) going to be different from
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// the frame register.
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if (Base->getOpcode() == ISD::FrameIndex)
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return true;
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if (Disp) {
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// Always use LA(Y) if there is a base, displacement and index.
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if (Index)
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return true;
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// Always use LA if the displacement is small enough. It should always
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// be no worse than AGHI (and better if it avoids a move).
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if (isUInt<12>(Disp))
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return true;
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// For similar reasons, always use LAY if the constant is too big for AGHI.
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// LAY should be no worse than AGFI.
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if (!isInt<16>(Disp))
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return true;
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} else {
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// Don't use LA for plain registers.
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if (!Index)
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return false;
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// Don't use LA for plain addition if the index operand is only used
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// once. It should be a natural two-operand addition in that case.
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if (Index->hasOneUse())
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return false;
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// Prefer addition if the second operation is sign-extended, in the
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// hope of using AGF.
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unsigned IndexOpcode = Index->getOpcode();
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if (IndexOpcode == ISD::SIGN_EXTEND ||
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IndexOpcode == ISD::SIGN_EXTEND_INREG)
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return false;
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}
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// Don't use LA for two-operand addition if either operand is only
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// used once. The addition instructions are better in that case.
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if (Base->hasOneUse())
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return false;
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return true;
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}
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// Return true if Addr is suitable for AM, updating AM if so.
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bool SystemZDAGToDAGISel::selectAddress(SDValue Addr,
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SystemZAddressingMode &AM) {
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// Start out assuming that the address will need to be loaded separately,
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// then try to extend it as much as we can.
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AM.Base = Addr;
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// First try treating the address as a constant.
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if (Addr.getOpcode() == ISD::Constant &&
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expandDisp(AM, true, SDValue(), cast<ConstantSDNode>(Addr)))
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;
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else
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// Otherwise try expanding each component.
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while (expandAddress(AM, true) ||
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(AM.Index.getNode() && expandAddress(AM, false)))
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continue;
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// Reject cases where it isn't profitable to use LA(Y).
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if (AM.Form == SystemZAddressingMode::FormBDXLA &&
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!shouldUseLA(AM.Base.getNode(), AM.Disp, AM.Index.getNode()))
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return false;
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// Reject cases where the other instruction in a pair should be used.
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if (!isValidDisp(AM.DR, AM.Disp))
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return false;
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// Make sure that ADJDYNALLOC is included where necessary.
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if (AM.isDynAlloc() && !AM.IncludesDynAlloc)
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return false;
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DEBUG(AM.dump());
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return true;
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}
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// Insert a node into the DAG at least before Pos. This will reposition
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// the node as needed, and will assign it a node ID that is <= Pos's ID.
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// Note that this does *not* preserve the uniqueness of node IDs!
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// The selection DAG must no longer depend on their uniqueness when this
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// function is used.
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static void insertDAGNode(SelectionDAG *DAG, SDNode *Pos, SDValue N) {
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if (N.getNode()->getNodeId() == -1 ||
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N.getNode()->getNodeId() > Pos->getNodeId()) {
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DAG->RepositionNode(Pos, N.getNode());
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N.getNode()->setNodeId(Pos->getNodeId());
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}
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}
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void SystemZDAGToDAGISel::getAddressOperands(const SystemZAddressingMode &AM,
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EVT VT, SDValue &Base,
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SDValue &Disp) {
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Base = AM.Base;
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if (!Base.getNode())
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|
// Register 0 means "no base". This is mostly useful for shifts.
|
|
Base = CurDAG->getRegister(0, VT);
|
|
else if (Base.getOpcode() == ISD::FrameIndex) {
|
|
// Lower a FrameIndex to a TargetFrameIndex.
|
|
int64_t FrameIndex = cast<FrameIndexSDNode>(Base)->getIndex();
|
|
Base = CurDAG->getTargetFrameIndex(FrameIndex, VT);
|
|
} else if (Base.getValueType() != VT) {
|
|
// Truncate values from i64 to i32, for shifts.
|
|
assert(VT == MVT::i32 && Base.getValueType() == MVT::i64 &&
|
|
"Unexpected truncation");
|
|
SDLoc DL(Base);
|
|
SDValue Trunc = CurDAG->getNode(ISD::TRUNCATE, DL, VT, Base);
|
|
insertDAGNode(CurDAG, Base.getNode(), Trunc);
|
|
Base = Trunc;
|
|
}
|
|
|
|
// Lower the displacement to a TargetConstant.
|
|
Disp = CurDAG->getTargetConstant(AM.Disp, VT);
|
|
}
|
|
|
|
void SystemZDAGToDAGISel::getAddressOperands(const SystemZAddressingMode &AM,
|
|
EVT VT, SDValue &Base,
|
|
SDValue &Disp, SDValue &Index) {
|
|
getAddressOperands(AM, VT, Base, Disp);
|
|
|
|
Index = AM.Index;
|
|
if (!Index.getNode())
|
|
// Register 0 means "no index".
|
|
Index = CurDAG->getRegister(0, VT);
|
|
}
|
|
|
|
bool SystemZDAGToDAGISel::selectBDAddr(SystemZAddressingMode::DispRange DR,
|
|
SDValue Addr, SDValue &Base,
|
|
SDValue &Disp) {
|
|
SystemZAddressingMode AM(SystemZAddressingMode::FormBD, DR);
|
|
if (!selectAddress(Addr, AM))
|
|
return false;
|
|
|
|
getAddressOperands(AM, Addr.getValueType(), Base, Disp);
|
|
return true;
|
|
}
|
|
|
|
bool SystemZDAGToDAGISel::selectBDXAddr(SystemZAddressingMode::AddrForm Form,
|
|
SystemZAddressingMode::DispRange DR,
|
|
SDValue Addr, SDValue &Base,
|
|
SDValue &Disp, SDValue &Index) {
|
|
SystemZAddressingMode AM(Form, DR);
|
|
if (!selectAddress(Addr, AM))
|
|
return false;
|
|
|
|
getAddressOperands(AM, Addr.getValueType(), Base, Disp, Index);
|
|
return true;
|
|
}
|
|
|
|
// Return true if Mask matches the regexp 0*1+0*, given that zero masks
|
|
// have already been filtered out. Store the first set bit in LSB and
|
|
// the number of set bits in Length if so.
|
|
static bool isStringOfOnes(uint64_t Mask, unsigned &LSB, unsigned &Length) {
|
|
unsigned First = findFirstSet(Mask);
|
|
uint64_t Top = (Mask >> First) + 1;
|
|
if ((Top & -Top) == Top)
|
|
{
|
|
LSB = First;
|
|
Length = findFirstSet(Top);
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
// Return a mask with Count low bits set.
|
|
static uint64_t allOnes(unsigned int Count) {
|
|
return Count == 0 ? 0 : (uint64_t(1) << (Count - 1) << 1) - 1;
|
|
}
|
|
|
|
// Return true if RISBG can be used to extract the bits in Mask from
|
|
// a value that has BitSize bits. Store the start and end operands
|
|
// (I3 and I4) in Start and End if so.
|
|
static bool isRISBGMask(uint64_t Mask, unsigned BitSize, unsigned &Start,
|
|
unsigned &End) {
|
|
// Reject trivial all-zero and all-one masks.
|
|
uint64_t Used = allOnes(BitSize);
|
|
if (Mask == 0 || Mask == Used)
|
|
return false;
|
|
|
|
// Handle the 1+0+ or 0+1+0* cases. Start then specifies the index of
|
|
// the msb and End specifies the index of the lsb.
|
|
unsigned LSB, Length;
|
|
if (isStringOfOnes(Mask, LSB, Length))
|
|
{
|
|
Start = 63 - (LSB + Length - 1);
|
|
End = 63 - LSB;
|
|
return true;
|
|
}
|
|
|
|
// Handle the wrap-around 1+0+1+ cases. Start then specifies the msb
|
|
// of the low 1s and End specifies the lsb of the high 1s.
|
|
if (isStringOfOnes(Mask ^ Used, LSB, Length))
|
|
{
|
|
assert(LSB > 0 && "Bottom bit must be set");
|
|
assert(LSB + Length < BitSize && "Top bit must be set");
|
|
Start = 63 - (LSB - 1);
|
|
End = 63 - (LSB + Length);
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
SDValue SystemZDAGToDAGISel::getUNDEF64(SDLoc DL) {
|
|
SDNode *N = CurDAG->getMachineNode(TargetOpcode::IMPLICIT_DEF, DL, MVT::i64);
|
|
return SDValue(N, 0);
|
|
}
|
|
|
|
SDValue SystemZDAGToDAGISel::convertTo(SDLoc DL, EVT VT, SDValue N) {
|
|
if (N.getValueType() == MVT::i32 && VT == MVT::i64) {
|
|
SDValue Index = CurDAG->getTargetConstant(SystemZ::subreg_32bit, MVT::i64);
|
|
SDNode *Insert = CurDAG->getMachineNode(TargetOpcode::INSERT_SUBREG,
|
|
DL, VT, getUNDEF64(DL), N, Index);
|
|
return SDValue(Insert, 0);
|
|
}
|
|
if (N.getValueType() == MVT::i64 && VT == MVT::i32) {
|
|
SDValue Index = CurDAG->getTargetConstant(SystemZ::subreg_32bit, MVT::i64);
|
|
SDNode *Extract = CurDAG->getMachineNode(TargetOpcode::EXTRACT_SUBREG,
|
|
DL, VT, N, Index);
|
|
return SDValue(Extract, 0);
|
|
}
|
|
assert(N.getValueType() == VT && "Unexpected value types");
|
|
return N;
|
|
}
|
|
|
|
SDNode *SystemZDAGToDAGISel::tryRISBGForAND(SDNode *N) {
|
|
EVT VT = N->getValueType(0);
|
|
unsigned BitSize = VT.getSizeInBits();
|
|
unsigned Start, End;
|
|
ConstantSDNode *MaskNode =
|
|
dyn_cast<ConstantSDNode>(N->getOperand(1).getNode());
|
|
if (!MaskNode)
|
|
return 0;
|
|
|
|
SDValue Input = N->getOperand(0);
|
|
uint64_t Mask = MaskNode->getZExtValue();
|
|
if (!isRISBGMask(Mask, BitSize, Start, End)) {
|
|
APInt KnownZero, KnownOne;
|
|
CurDAG->ComputeMaskedBits(Input, KnownZero, KnownOne);
|
|
Mask |= KnownZero.getZExtValue();
|
|
if (!isRISBGMask(Mask, BitSize, Start, End))
|
|
return 0;
|
|
}
|
|
|
|
unsigned Rotate = 0;
|
|
if (Input->getOpcode() == ISD::ROTL && BitSize == 64) {
|
|
// Any 64-bit rotate left can be merged into the RISBG.
|
|
if (ConstantSDNode *CountNode =
|
|
dyn_cast<ConstantSDNode>(Input.getOperand(1).getNode())) {
|
|
Rotate = CountNode->getZExtValue() & (BitSize - 1);
|
|
Input = Input->getOperand(0);
|
|
}
|
|
} else if (Input->getOpcode() == ISD::SHL) {
|
|
// Try to convert (and (shl X, count), mask) into
|
|
// (and (rotl X, count), mask&(~0<<count)), where the new mask
|
|
// removes bits from the original mask that are zeroed by the shl
|
|
// but that are not necessarily zero in X.
|
|
if (ConstantSDNode *CountNode =
|
|
dyn_cast<ConstantSDNode>(Input.getOperand(1).getNode())) {
|
|
uint64_t Count = CountNode->getZExtValue();
|
|
if (Count > 0 &&
|
|
Count < BitSize &&
|
|
isRISBGMask(Mask & (allOnes(BitSize - Count) << Count),
|
|
BitSize, Start, End)) {
|
|
Rotate = Count;
|
|
Input = Input->getOperand(0);
|
|
}
|
|
}
|
|
} else if (Input->getOpcode() == ISD::SRL) {
|
|
// Try to convert (and (srl X, count), mask) into
|
|
// (and (rotl X, size-count), mask&(~0>>count)), which is similar
|
|
// to SLL above.
|
|
if (ConstantSDNode *CountNode =
|
|
dyn_cast<ConstantSDNode>(Input.getOperand(1).getNode())) {
|
|
uint64_t Count = CountNode->getZExtValue();
|
|
if (Count > 0 &&
|
|
Count < BitSize &&
|
|
isRISBGMask(Mask & allOnes(BitSize - Count), BitSize, Start, End)) {
|
|
Rotate = 64 - Count;
|
|
Input = Input->getOperand(0);
|
|
}
|
|
}
|
|
} else if (Start <= End && Input->getOpcode() == ISD::SRA) {
|
|
// Try to convert (and (sra X, count), mask) into
|
|
// (and (rotl X, size-count), mask). The mask must not include
|
|
// any sign bits.
|
|
if (ConstantSDNode *CountNode =
|
|
dyn_cast<ConstantSDNode>(Input.getOperand(1).getNode())) {
|
|
uint64_t Count = CountNode->getZExtValue();
|
|
if (Count > 0 && Count < BitSize && Start >= 64 - (BitSize - Count)) {
|
|
Rotate = 64 - Count;
|
|
Input = Input->getOperand(0);
|
|
}
|
|
}
|
|
}
|
|
|
|
// Prefer register extensions like LLC over RSIBG.
|
|
if (Rotate == 0 && (Start == 32 || Start == 48 || Start == 56) && End == 63)
|
|
return 0;
|
|
|
|
SDValue Ops[5] = {
|
|
getUNDEF64(SDLoc(N)),
|
|
convertTo(SDLoc(N), MVT::i64, Input),
|
|
CurDAG->getTargetConstant(Start, MVT::i32),
|
|
CurDAG->getTargetConstant(End | 128, MVT::i32),
|
|
CurDAG->getTargetConstant(Rotate, MVT::i32)
|
|
};
|
|
N = CurDAG->getMachineNode(SystemZ::RISBG, SDLoc(N), MVT::i64, Ops);
|
|
return convertTo(SDLoc(N), VT, SDValue(N, 0)).getNode();
|
|
}
|
|
|
|
SDNode *SystemZDAGToDAGISel::splitLargeImmediate(unsigned Opcode, SDNode *Node,
|
|
SDValue Op0, uint64_t UpperVal,
|
|
uint64_t LowerVal) {
|
|
EVT VT = Node->getValueType(0);
|
|
SDLoc DL(Node);
|
|
SDValue Upper = CurDAG->getConstant(UpperVal, VT);
|
|
if (Op0.getNode())
|
|
Upper = CurDAG->getNode(Opcode, DL, VT, Op0, Upper);
|
|
Upper = SDValue(Select(Upper.getNode()), 0);
|
|
|
|
SDValue Lower = CurDAG->getConstant(LowerVal, VT);
|
|
SDValue Or = CurDAG->getNode(Opcode, DL, VT, Upper, Lower);
|
|
return Or.getNode();
|
|
}
|
|
|
|
// N is a (store (load ...), ...) pattern. Return true if it can use MVC.
|
|
bool SystemZDAGToDAGISel::storeLoadCanUseMVC(SDNode *N) const {
|
|
StoreSDNode *Store = cast<StoreSDNode>(N);
|
|
LoadSDNode *Load = cast<LoadSDNode>(Store->getValue().getNode());
|
|
|
|
// MVC is logically a bytewise copy, so can't be used for volatile accesses.
|
|
if (Load->isVolatile() || Store->isVolatile())
|
|
return false;
|
|
|
|
// Prefer not to use MVC if either address can use ... RELATIVE LONG
|
|
// instructions.
|
|
assert(Load->getMemoryVT() == Store->getMemoryVT() &&
|
|
"Should already have checked that the types match");
|
|
uint64_t Size = Load->getMemoryVT().getStoreSize();
|
|
if (Size > 1 && Size <= 8) {
|
|
// Prefer LHRL, LRL and LGRL.
|
|
if (Load->getBasePtr().getOpcode() == SystemZISD::PCREL_WRAPPER)
|
|
return false;
|
|
// Prefer STHRL, STRL and STGRL.
|
|
if (Store->getBasePtr().getOpcode() == SystemZISD::PCREL_WRAPPER)
|
|
return false;
|
|
}
|
|
|
|
// There's no chance of overlap if the load is invariant.
|
|
if (Load->isInvariant())
|
|
return true;
|
|
|
|
// If both operands are aligned, they must be equal or not overlap.
|
|
if (Load->getAlignment() >= Size && Store->getAlignment() >= Size)
|
|
return true;
|
|
|
|
// Otherwise we need to check whether there's an alias.
|
|
const Value *V1 = Load->getSrcValue();
|
|
const Value *V2 = Store->getSrcValue();
|
|
if (!V1 || !V2)
|
|
return false;
|
|
|
|
int64_t End1 = Load->getSrcValueOffset() + Size;
|
|
int64_t End2 = Store->getSrcValueOffset() + Size;
|
|
return !AA->alias(AliasAnalysis::Location(V1, End1, Load->getTBAAInfo()),
|
|
AliasAnalysis::Location(V2, End2, Store->getTBAAInfo()));
|
|
}
|
|
|
|
SDNode *SystemZDAGToDAGISel::Select(SDNode *Node) {
|
|
// Dump information about the Node being selected
|
|
DEBUG(errs() << "Selecting: "; Node->dump(CurDAG); errs() << "\n");
|
|
|
|
// If we have a custom node, we already have selected!
|
|
if (Node->isMachineOpcode()) {
|
|
DEBUG(errs() << "== "; Node->dump(CurDAG); errs() << "\n");
|
|
return 0;
|
|
}
|
|
|
|
unsigned Opcode = Node->getOpcode();
|
|
SDNode *ResNode = 0;
|
|
switch (Opcode) {
|
|
case ISD::OR:
|
|
case ISD::XOR:
|
|
// If this is a 64-bit operation in which both 32-bit halves are nonzero,
|
|
// split the operation into two.
|
|
if (Node->getValueType(0) == MVT::i64)
|
|
if (ConstantSDNode *Op1 = dyn_cast<ConstantSDNode>(Node->getOperand(1))) {
|
|
uint64_t Val = Op1->getZExtValue();
|
|
if (!SystemZ::isImmLF(Val) && !SystemZ::isImmHF(Val))
|
|
Node = splitLargeImmediate(Opcode, Node, Node->getOperand(0),
|
|
Val - uint32_t(Val), uint32_t(Val));
|
|
}
|
|
break;
|
|
|
|
case ISD::AND:
|
|
ResNode = tryRISBGForAND(Node);
|
|
break;
|
|
|
|
case ISD::Constant:
|
|
// If this is a 64-bit constant that is out of the range of LLILF,
|
|
// LLIHF and LGFI, split it into two 32-bit pieces.
|
|
if (Node->getValueType(0) == MVT::i64) {
|
|
uint64_t Val = cast<ConstantSDNode>(Node)->getZExtValue();
|
|
if (!SystemZ::isImmLF(Val) && !SystemZ::isImmHF(Val) && !isInt<32>(Val))
|
|
Node = splitLargeImmediate(ISD::OR, Node, SDValue(),
|
|
Val - uint32_t(Val), uint32_t(Val));
|
|
}
|
|
break;
|
|
|
|
case ISD::ATOMIC_LOAD_SUB:
|
|
// Try to convert subtractions of constants to additions.
|
|
if (ConstantSDNode *Op2 = dyn_cast<ConstantSDNode>(Node->getOperand(2))) {
|
|
uint64_t Value = -Op2->getZExtValue();
|
|
EVT VT = Node->getValueType(0);
|
|
if (VT == MVT::i32 || isInt<32>(Value)) {
|
|
SDValue Ops[] = { Node->getOperand(0), Node->getOperand(1),
|
|
CurDAG->getConstant(int32_t(Value), VT) };
|
|
Node = CurDAG->MorphNodeTo(Node, ISD::ATOMIC_LOAD_ADD,
|
|
Node->getVTList(), Ops, array_lengthof(Ops));
|
|
}
|
|
}
|
|
break;
|
|
}
|
|
|
|
// Select the default instruction
|
|
if (!ResNode)
|
|
ResNode = SelectCode(Node);
|
|
|
|
DEBUG(errs() << "=> ";
|
|
if (ResNode == NULL || ResNode == Node)
|
|
Node->dump(CurDAG);
|
|
else
|
|
ResNode->dump(CurDAG);
|
|
errs() << "\n";
|
|
);
|
|
return ResNode;
|
|
}
|
|
|
|
bool SystemZDAGToDAGISel::
|
|
SelectInlineAsmMemoryOperand(const SDValue &Op,
|
|
char ConstraintCode,
|
|
std::vector<SDValue> &OutOps) {
|
|
assert(ConstraintCode == 'm' && "Unexpected constraint code");
|
|
// Accept addresses with short displacements, which are compatible
|
|
// with Q, R, S and T. But keep the index operand for future expansion.
|
|
SDValue Base, Disp, Index;
|
|
if (!selectBDXAddr(SystemZAddressingMode::FormBD,
|
|
SystemZAddressingMode::Disp12Only,
|
|
Op, Base, Disp, Index))
|
|
return true;
|
|
OutOps.push_back(Base);
|
|
OutOps.push_back(Disp);
|
|
OutOps.push_back(Index);
|
|
return false;
|
|
}
|