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	slots. The AsmPrinter will use this information to determine whether to print a spill/reload comment. Remove default argument values. It's too easy to pass a wrong argument value when multiple arguments have default values. Make everything explicit to trap bugs early. Update all targets to adhere to the new interfaces.. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@87022 91177308-0d34-0410-b5e6-96231b3b80d8
		
			
				
	
	
		
			857 lines
		
	
	
		
			32 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			857 lines
		
	
	
		
			32 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
//===-- SystemZISelLowering.cpp - SystemZ DAG Lowering Implementation  -----==//
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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 implements the SystemZTargetLowering class.
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//
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//===----------------------------------------------------------------------===//
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#define DEBUG_TYPE "systemz-lower"
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#include "SystemZISelLowering.h"
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#include "SystemZ.h"
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#include "SystemZTargetMachine.h"
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#include "SystemZSubtarget.h"
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#include "llvm/DerivedTypes.h"
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#include "llvm/Function.h"
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#include "llvm/Intrinsics.h"
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#include "llvm/CallingConv.h"
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#include "llvm/GlobalVariable.h"
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#include "llvm/GlobalAlias.h"
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#include "llvm/CodeGen/CallingConvLower.h"
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#include "llvm/CodeGen/MachineFrameInfo.h"
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#include "llvm/CodeGen/MachineFunction.h"
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#include "llvm/CodeGen/MachineInstrBuilder.h"
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#include "llvm/CodeGen/MachineRegisterInfo.h"
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#include "llvm/CodeGen/PseudoSourceValue.h"
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#include "llvm/CodeGen/SelectionDAGISel.h"
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#include "llvm/CodeGen/ValueTypes.h"
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#include "llvm/Target/TargetOptions.h"
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#include "llvm/Target/TargetLoweringObjectFile.h"
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#include "llvm/Support/Debug.h"
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#include "llvm/Support/ErrorHandling.h"
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#include "llvm/Support/raw_ostream.h"
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#include "llvm/ADT/VectorExtras.h"
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using namespace llvm;
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SystemZTargetLowering::SystemZTargetLowering(SystemZTargetMachine &tm) :
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  TargetLowering(tm, new TargetLoweringObjectFileELF()),
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  Subtarget(*tm.getSubtargetImpl()), TM(tm) {
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  RegInfo = TM.getRegisterInfo();
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  // Set up the register classes.
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  addRegisterClass(MVT::i32,  SystemZ::GR32RegisterClass);
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  addRegisterClass(MVT::i64,  SystemZ::GR64RegisterClass);
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  addRegisterClass(MVT::v2i32,SystemZ::GR64PRegisterClass);
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  addRegisterClass(MVT::v2i64,SystemZ::GR128RegisterClass);
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  if (!UseSoftFloat) {
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    addRegisterClass(MVT::f32, SystemZ::FP32RegisterClass);
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    addRegisterClass(MVT::f64, SystemZ::FP64RegisterClass);
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  }
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  // Compute derived properties from the register classes
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  computeRegisterProperties();
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  // Set shifts properties
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  setShiftAmountType(MVT::i64);
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  // Provide all sorts of operation actions
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  setLoadExtAction(ISD::SEXTLOAD, MVT::i1, Promote);
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  setLoadExtAction(ISD::ZEXTLOAD, MVT::i1, Promote);
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  setLoadExtAction(ISD::EXTLOAD,  MVT::i1, Promote);
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  setLoadExtAction(ISD::SEXTLOAD, MVT::f32, Expand);
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  setLoadExtAction(ISD::ZEXTLOAD, MVT::f32, Expand);
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  setLoadExtAction(ISD::EXTLOAD,  MVT::f32, Expand);
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  setLoadExtAction(ISD::SEXTLOAD, MVT::f64, Expand);
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  setLoadExtAction(ISD::ZEXTLOAD, MVT::f64, Expand);
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  setLoadExtAction(ISD::EXTLOAD,  MVT::f64, Expand);
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  setStackPointerRegisterToSaveRestore(SystemZ::R15D);
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  // TODO: It may be better to default to latency-oriented scheduling, however
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  // LLVM's current latency-oriented scheduler can't handle physreg definitions
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  // such as SystemZ has with PSW, so set this to the register-pressure
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  // scheduler, because it can.
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  setSchedulingPreference(SchedulingForRegPressure);
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  setBooleanContents(ZeroOrOneBooleanContent);
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  setOperationAction(ISD::BR_JT,            MVT::Other, Expand);
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  setOperationAction(ISD::BRCOND,           MVT::Other, Expand);
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  setOperationAction(ISD::BR_CC,            MVT::i32, Custom);
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  setOperationAction(ISD::BR_CC,            MVT::i64, Custom);
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  setOperationAction(ISD::BR_CC,            MVT::f32, Custom);
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  setOperationAction(ISD::BR_CC,            MVT::f64, Custom);
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  setOperationAction(ISD::ConstantPool,     MVT::i32, Custom);
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  setOperationAction(ISD::ConstantPool,     MVT::i64, Custom);
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  setOperationAction(ISD::GlobalAddress,    MVT::i64, Custom);
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  setOperationAction(ISD::JumpTable,        MVT::i64, Custom);
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  setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i64, Expand);
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  setOperationAction(ISD::SDIV,             MVT::i32, Expand);
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  setOperationAction(ISD::UDIV,             MVT::i32, Expand);
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  setOperationAction(ISD::SDIV,             MVT::i64, Expand);
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  setOperationAction(ISD::UDIV,             MVT::i64, Expand);
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  setOperationAction(ISD::SREM,             MVT::i32, Expand);
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  setOperationAction(ISD::UREM,             MVT::i32, Expand);
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  setOperationAction(ISD::SREM,             MVT::i64, Expand);
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  setOperationAction(ISD::UREM,             MVT::i64, Expand);
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  setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i1, Expand);
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  setOperationAction(ISD::CTPOP,            MVT::i32, Expand);
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  setOperationAction(ISD::CTPOP,            MVT::i64, Expand);
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  setOperationAction(ISD::CTTZ,             MVT::i32, Expand);
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  setOperationAction(ISD::CTTZ,             MVT::i64, Expand);
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  setOperationAction(ISD::CTLZ,             MVT::i32, Promote);
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  setOperationAction(ISD::CTLZ,             MVT::i64, Legal);
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  // FIXME: Can we lower these 2 efficiently?
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  setOperationAction(ISD::SETCC,            MVT::i32, Expand);
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  setOperationAction(ISD::SETCC,            MVT::i64, Expand);
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  setOperationAction(ISD::SETCC,            MVT::f32, Expand);
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  setOperationAction(ISD::SETCC,            MVT::f64, Expand);
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  setOperationAction(ISD::SELECT,           MVT::i32, Expand);
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  setOperationAction(ISD::SELECT,           MVT::i64, Expand);
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  setOperationAction(ISD::SELECT,           MVT::f32, Expand);
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  setOperationAction(ISD::SELECT,           MVT::f64, Expand);
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  setOperationAction(ISD::SELECT_CC,        MVT::i32, Custom);
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  setOperationAction(ISD::SELECT_CC,        MVT::i64, Custom);
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  setOperationAction(ISD::SELECT_CC,        MVT::f32, Custom);
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  setOperationAction(ISD::SELECT_CC,        MVT::f64, Custom);
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  setOperationAction(ISD::MULHS,            MVT::i64, Expand);
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  setOperationAction(ISD::SMUL_LOHI,        MVT::i64, Expand);
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  // FIXME: Can we support these natively?
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  setOperationAction(ISD::UMUL_LOHI,        MVT::i64, Expand);
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  setOperationAction(ISD::SRL_PARTS,        MVT::i64, Expand);
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  setOperationAction(ISD::SHL_PARTS,        MVT::i64, Expand);
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  setOperationAction(ISD::SRA_PARTS,        MVT::i64, Expand);
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  // Lower some FP stuff
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  setOperationAction(ISD::FSIN,             MVT::f32, Expand);
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  setOperationAction(ISD::FSIN,             MVT::f64, Expand);
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  setOperationAction(ISD::FCOS,             MVT::f32, Expand);
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  setOperationAction(ISD::FCOS,             MVT::f64, Expand);
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  setOperationAction(ISD::FREM,             MVT::f32, Expand);
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  setOperationAction(ISD::FREM,             MVT::f64, Expand);
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  // We have only 64-bit bitconverts
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  setOperationAction(ISD::BIT_CONVERT,      MVT::f32, Expand);
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  setOperationAction(ISD::BIT_CONVERT,      MVT::i32, Expand);
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  setOperationAction(ISD::UINT_TO_FP,       MVT::i32, Expand);
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  setOperationAction(ISD::UINT_TO_FP,       MVT::i64, Expand);
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  setOperationAction(ISD::FP_TO_UINT,       MVT::i32, Expand);
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  setOperationAction(ISD::FP_TO_UINT,       MVT::i64, Expand);
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  setTruncStoreAction(MVT::f64, MVT::f32, Expand);
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}
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SDValue SystemZTargetLowering::LowerOperation(SDValue Op, SelectionDAG &DAG) {
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  switch (Op.getOpcode()) {
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  case ISD::BR_CC:            return LowerBR_CC(Op, DAG);
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  case ISD::SELECT_CC:        return LowerSELECT_CC(Op, DAG);
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  case ISD::GlobalAddress:    return LowerGlobalAddress(Op, DAG);
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  case ISD::JumpTable:        return LowerJumpTable(Op, DAG);
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  case ISD::ConstantPool:     return LowerConstantPool(Op, DAG);
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  default:
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    llvm_unreachable("Should not custom lower this!");
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    return SDValue();
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  }
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}
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bool SystemZTargetLowering::isFPImmLegal(const APFloat &Imm, EVT VT) const {
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  if (UseSoftFloat || (VT != MVT::f32 && VT != MVT::f64))
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    return false;
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  // +0.0  lzer
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  // +0.0f lzdr
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  // -0.0  lzer + lner
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  // -0.0f lzdr + lndr
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  return Imm.isZero() || Imm.isNegZero();
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}
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//===----------------------------------------------------------------------===//
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//                       SystemZ Inline Assembly Support
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//===----------------------------------------------------------------------===//
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/// getConstraintType - Given a constraint letter, return the type of
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/// constraint it is for this target.
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TargetLowering::ConstraintType
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SystemZTargetLowering::getConstraintType(const std::string &Constraint) const {
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  if (Constraint.size() == 1) {
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    switch (Constraint[0]) {
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    case 'r':
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      return C_RegisterClass;
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    default:
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      break;
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    }
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  }
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  return TargetLowering::getConstraintType(Constraint);
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}
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std::pair<unsigned, const TargetRegisterClass*>
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SystemZTargetLowering::
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getRegForInlineAsmConstraint(const std::string &Constraint,
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                             EVT VT) const {
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  if (Constraint.size() == 1) {
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    // GCC Constraint Letters
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    switch (Constraint[0]) {
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    default: break;
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    case 'r':   // GENERAL_REGS
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      if (VT == MVT::i32)
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        return std::make_pair(0U, SystemZ::GR32RegisterClass);
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      else if (VT == MVT::i128)
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        return std::make_pair(0U, SystemZ::GR128RegisterClass);
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      return std::make_pair(0U, SystemZ::GR64RegisterClass);
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    }
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  }
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  return TargetLowering::getRegForInlineAsmConstraint(Constraint, VT);
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}
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//===----------------------------------------------------------------------===//
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//                      Calling Convention Implementation
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//===----------------------------------------------------------------------===//
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#include "SystemZGenCallingConv.inc"
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SDValue
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SystemZTargetLowering::LowerFormalArguments(SDValue Chain,
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                                            CallingConv::ID CallConv,
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                                            bool isVarArg,
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                                            const SmallVectorImpl<ISD::InputArg>
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                                              &Ins,
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                                            DebugLoc dl,
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                                            SelectionDAG &DAG,
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                                            SmallVectorImpl<SDValue> &InVals) {
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  switch (CallConv) {
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  default:
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    llvm_unreachable("Unsupported calling convention");
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  case CallingConv::C:
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  case CallingConv::Fast:
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    return LowerCCCArguments(Chain, CallConv, isVarArg, Ins, dl, DAG, InVals);
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  }
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}
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SDValue
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SystemZTargetLowering::LowerCall(SDValue Chain, SDValue Callee,
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                                 CallingConv::ID CallConv, bool isVarArg,
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                                 bool isTailCall,
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                                 const SmallVectorImpl<ISD::OutputArg> &Outs,
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                                 const SmallVectorImpl<ISD::InputArg> &Ins,
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                                 DebugLoc dl, SelectionDAG &DAG,
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                                 SmallVectorImpl<SDValue> &InVals) {
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  switch (CallConv) {
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  default:
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    llvm_unreachable("Unsupported calling convention");
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  case CallingConv::Fast:
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  case CallingConv::C:
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    return LowerCCCCallTo(Chain, Callee, CallConv, isVarArg, isTailCall,
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                          Outs, Ins, dl, DAG, InVals);
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  }
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}
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/// LowerCCCArguments - transform physical registers into virtual registers and
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/// generate load operations for arguments places on the stack.
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// FIXME: struct return stuff
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// FIXME: varargs
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SDValue
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SystemZTargetLowering::LowerCCCArguments(SDValue Chain,
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                                         CallingConv::ID CallConv,
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                                         bool isVarArg,
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                                         const SmallVectorImpl<ISD::InputArg>
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                                           &Ins,
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                                         DebugLoc dl,
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                                         SelectionDAG &DAG,
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                                         SmallVectorImpl<SDValue> &InVals) {
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  MachineFunction &MF = DAG.getMachineFunction();
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  MachineFrameInfo *MFI = MF.getFrameInfo();
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  MachineRegisterInfo &RegInfo = MF.getRegInfo();
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  // Assign locations to all of the incoming arguments.
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  SmallVector<CCValAssign, 16> ArgLocs;
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  CCState CCInfo(CallConv, isVarArg, getTargetMachine(),
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                 ArgLocs, *DAG.getContext());
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  CCInfo.AnalyzeFormalArguments(Ins, CC_SystemZ);
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  if (isVarArg)
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    llvm_report_error("Varargs not supported yet");
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  for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) {
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    SDValue ArgValue;
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    CCValAssign &VA = ArgLocs[i];
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    EVT LocVT = VA.getLocVT();
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    if (VA.isRegLoc()) {
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      // Arguments passed in registers
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      TargetRegisterClass *RC;
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      switch (LocVT.getSimpleVT().SimpleTy) {
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      default:
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#ifndef NDEBUG
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        errs() << "LowerFormalArguments Unhandled argument type: "
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             << LocVT.getSimpleVT().SimpleTy
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             << "\n";
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#endif
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        llvm_unreachable(0);
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      case MVT::i64:
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        RC = SystemZ::GR64RegisterClass;
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        break;
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      case MVT::f32:
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        RC = SystemZ::FP32RegisterClass;
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        break;
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      case MVT::f64:
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        RC = SystemZ::FP64RegisterClass;
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        break;
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      }
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      unsigned VReg = RegInfo.createVirtualRegister(RC);
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      RegInfo.addLiveIn(VA.getLocReg(), VReg);
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      ArgValue = DAG.getCopyFromReg(Chain, dl, VReg, LocVT);
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    } else {
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      // Sanity check
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      assert(VA.isMemLoc());
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      // Create the nodes corresponding to a load from this parameter slot.
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      // Create the frame index object for this incoming parameter...
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      int FI = MFI->CreateFixedObject(LocVT.getSizeInBits()/8,
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                                      VA.getLocMemOffset(), true, false);
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      // Create the SelectionDAG nodes corresponding to a load
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      // from this parameter
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      SDValue FIN = DAG.getFrameIndex(FI, getPointerTy());
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      ArgValue = DAG.getLoad(LocVT, dl, Chain, FIN,
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                             PseudoSourceValue::getFixedStack(FI), 0);
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    }
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    // If this is an 8/16/32-bit value, it is really passed promoted to 64
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    // bits. Insert an assert[sz]ext to capture this, then truncate to the
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    // right size.
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    if (VA.getLocInfo() == CCValAssign::SExt)
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      ArgValue = DAG.getNode(ISD::AssertSext, dl, LocVT, ArgValue,
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                             DAG.getValueType(VA.getValVT()));
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    else if (VA.getLocInfo() == CCValAssign::ZExt)
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      ArgValue = DAG.getNode(ISD::AssertZext, dl, LocVT, ArgValue,
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                             DAG.getValueType(VA.getValVT()));
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    if (VA.getLocInfo() != CCValAssign::Full)
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      ArgValue = DAG.getNode(ISD::TRUNCATE, dl, VA.getValVT(), ArgValue);
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    InVals.push_back(ArgValue);
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  }
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  return Chain;
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}
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/// LowerCCCCallTo - functions arguments are copied from virtual regs to
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/// (physical regs)/(stack frame), CALLSEQ_START and CALLSEQ_END are emitted.
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/// TODO: sret.
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SDValue
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SystemZTargetLowering::LowerCCCCallTo(SDValue Chain, SDValue Callee,
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                                      CallingConv::ID CallConv, bool isVarArg,
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                                      bool isTailCall,
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                                      const SmallVectorImpl<ISD::OutputArg>
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                                        &Outs,
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                                      const SmallVectorImpl<ISD::InputArg> &Ins,
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                                      DebugLoc dl, SelectionDAG &DAG,
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                                      SmallVectorImpl<SDValue> &InVals) {
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  MachineFunction &MF = DAG.getMachineFunction();
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  // Offset to first argument stack slot.
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  const unsigned FirstArgOffset = 160;
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  // Analyze operands of the call, assigning locations to each operand.
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  SmallVector<CCValAssign, 16> ArgLocs;
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						|
  CCState CCInfo(CallConv, isVarArg, getTargetMachine(),
 | 
						|
                 ArgLocs, *DAG.getContext());
 | 
						|
 | 
						|
  CCInfo.AnalyzeCallOperands(Outs, CC_SystemZ);
 | 
						|
 | 
						|
  // Get a count of how many bytes are to be pushed on the stack.
 | 
						|
  unsigned NumBytes = CCInfo.getNextStackOffset();
 | 
						|
 | 
						|
  Chain = DAG.getCALLSEQ_START(Chain ,DAG.getConstant(NumBytes,
 | 
						|
                                                      getPointerTy(), true));
 | 
						|
 | 
						|
  SmallVector<std::pair<unsigned, SDValue>, 4> RegsToPass;
 | 
						|
  SmallVector<SDValue, 12> MemOpChains;
 | 
						|
  SDValue StackPtr;
 | 
						|
 | 
						|
  // Walk the register/memloc assignments, inserting copies/loads.
 | 
						|
  for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) {
 | 
						|
    CCValAssign &VA = ArgLocs[i];
 | 
						|
 | 
						|
    SDValue Arg = Outs[i].Val;
 | 
						|
 | 
						|
    // Promote the value if needed.
 | 
						|
    switch (VA.getLocInfo()) {
 | 
						|
      default: assert(0 && "Unknown loc info!");
 | 
						|
      case CCValAssign::Full: break;
 | 
						|
      case CCValAssign::SExt:
 | 
						|
        Arg = DAG.getNode(ISD::SIGN_EXTEND, dl, VA.getLocVT(), Arg);
 | 
						|
        break;
 | 
						|
      case CCValAssign::ZExt:
 | 
						|
        Arg = DAG.getNode(ISD::ZERO_EXTEND, dl, VA.getLocVT(), Arg);
 | 
						|
        break;
 | 
						|
      case CCValAssign::AExt:
 | 
						|
        Arg = DAG.getNode(ISD::ANY_EXTEND, dl, VA.getLocVT(), Arg);
 | 
						|
        break;
 | 
						|
    }
 | 
						|
 | 
						|
    // Arguments that can be passed on register must be kept at RegsToPass
 | 
						|
    // vector
 | 
						|
    if (VA.isRegLoc()) {
 | 
						|
      RegsToPass.push_back(std::make_pair(VA.getLocReg(), Arg));
 | 
						|
    } else {
 | 
						|
      assert(VA.isMemLoc());
 | 
						|
 | 
						|
      if (StackPtr.getNode() == 0)
 | 
						|
        StackPtr =
 | 
						|
          DAG.getCopyFromReg(Chain, dl,
 | 
						|
                             (RegInfo->hasFP(MF) ?
 | 
						|
                              SystemZ::R11D : SystemZ::R15D),
 | 
						|
                             getPointerTy());
 | 
						|
 | 
						|
      unsigned Offset = FirstArgOffset + VA.getLocMemOffset();
 | 
						|
      SDValue PtrOff = DAG.getNode(ISD::ADD, dl, getPointerTy(),
 | 
						|
                                   StackPtr,
 | 
						|
                                   DAG.getIntPtrConstant(Offset));
 | 
						|
 | 
						|
      MemOpChains.push_back(DAG.getStore(Chain, dl, Arg, PtrOff,
 | 
						|
                                         PseudoSourceValue::getStack(), Offset));
 | 
						|
    }
 | 
						|
  }
 | 
						|
 | 
						|
  // Transform all store nodes into one single node because all store nodes are
 | 
						|
  // independent of each other.
 | 
						|
  if (!MemOpChains.empty())
 | 
						|
    Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other,
 | 
						|
                        &MemOpChains[0], MemOpChains.size());
 | 
						|
 | 
						|
  // Build a sequence of copy-to-reg nodes chained together with token chain and
 | 
						|
  // flag operands which copy the outgoing args into registers.  The InFlag in
 | 
						|
  // necessary since all emited instructions must be stuck together.
 | 
						|
  SDValue InFlag;
 | 
						|
  for (unsigned i = 0, e = RegsToPass.size(); i != e; ++i) {
 | 
						|
    Chain = DAG.getCopyToReg(Chain, dl, RegsToPass[i].first,
 | 
						|
                             RegsToPass[i].second, InFlag);
 | 
						|
    InFlag = Chain.getValue(1);
 | 
						|
  }
 | 
						|
 | 
						|
  // If the callee is a GlobalAddress node (quite common, every direct call is)
 | 
						|
  // turn it into a TargetGlobalAddress node so that legalize doesn't hack it.
 | 
						|
  // Likewise ExternalSymbol -> TargetExternalSymbol.
 | 
						|
  if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee))
 | 
						|
    Callee = DAG.getTargetGlobalAddress(G->getGlobal(), getPointerTy());
 | 
						|
  else if (ExternalSymbolSDNode *E = dyn_cast<ExternalSymbolSDNode>(Callee))
 | 
						|
    Callee = DAG.getTargetExternalSymbol(E->getSymbol(), getPointerTy());
 | 
						|
 | 
						|
  // Returns a chain & a flag for retval copy to use.
 | 
						|
  SDVTList NodeTys = DAG.getVTList(MVT::Other, MVT::Flag);
 | 
						|
  SmallVector<SDValue, 8> Ops;
 | 
						|
  Ops.push_back(Chain);
 | 
						|
  Ops.push_back(Callee);
 | 
						|
 | 
						|
  // Add argument registers to the end of the list so that they are
 | 
						|
  // known live into the call.
 | 
						|
  for (unsigned i = 0, e = RegsToPass.size(); i != e; ++i)
 | 
						|
    Ops.push_back(DAG.getRegister(RegsToPass[i].first,
 | 
						|
                                  RegsToPass[i].second.getValueType()));
 | 
						|
 | 
						|
  if (InFlag.getNode())
 | 
						|
    Ops.push_back(InFlag);
 | 
						|
 | 
						|
  Chain = DAG.getNode(SystemZISD::CALL, dl, NodeTys, &Ops[0], Ops.size());
 | 
						|
  InFlag = Chain.getValue(1);
 | 
						|
 | 
						|
  // Create the CALLSEQ_END node.
 | 
						|
  Chain = DAG.getCALLSEQ_END(Chain,
 | 
						|
                             DAG.getConstant(NumBytes, getPointerTy(), true),
 | 
						|
                             DAG.getConstant(0, getPointerTy(), true),
 | 
						|
                             InFlag);
 | 
						|
  InFlag = Chain.getValue(1);
 | 
						|
 | 
						|
  // Handle result values, copying them out of physregs into vregs that we
 | 
						|
  // return.
 | 
						|
  return LowerCallResult(Chain, InFlag, CallConv, isVarArg, Ins, dl,
 | 
						|
                         DAG, InVals);
 | 
						|
}
 | 
						|
 | 
						|
/// LowerCallResult - Lower the result values of a call into the
 | 
						|
/// appropriate copies out of appropriate physical registers.
 | 
						|
///
 | 
						|
SDValue
 | 
						|
SystemZTargetLowering::LowerCallResult(SDValue Chain, SDValue InFlag,
 | 
						|
                                       CallingConv::ID CallConv, bool isVarArg,
 | 
						|
                                       const SmallVectorImpl<ISD::InputArg>
 | 
						|
                                         &Ins,
 | 
						|
                                       DebugLoc dl, SelectionDAG &DAG,
 | 
						|
                                       SmallVectorImpl<SDValue> &InVals) {
 | 
						|
 | 
						|
  // Assign locations to each value returned by this call.
 | 
						|
  SmallVector<CCValAssign, 16> RVLocs;
 | 
						|
  CCState CCInfo(CallConv, isVarArg, getTargetMachine(), RVLocs,
 | 
						|
                 *DAG.getContext());
 | 
						|
 | 
						|
  CCInfo.AnalyzeCallResult(Ins, RetCC_SystemZ);
 | 
						|
 | 
						|
  // Copy all of the result registers out of their specified physreg.
 | 
						|
  for (unsigned i = 0; i != RVLocs.size(); ++i) {
 | 
						|
    CCValAssign &VA = RVLocs[i];
 | 
						|
 | 
						|
    Chain = DAG.getCopyFromReg(Chain, dl, VA.getLocReg(),
 | 
						|
                               VA.getLocVT(), InFlag).getValue(1);
 | 
						|
    SDValue RetValue = Chain.getValue(0);
 | 
						|
    InFlag = Chain.getValue(2);
 | 
						|
 | 
						|
    // If this is an 8/16/32-bit value, it is really passed promoted to 64
 | 
						|
    // bits. Insert an assert[sz]ext to capture this, then truncate to the
 | 
						|
    // right size.
 | 
						|
    if (VA.getLocInfo() == CCValAssign::SExt)
 | 
						|
      RetValue = DAG.getNode(ISD::AssertSext, dl, VA.getLocVT(), RetValue,
 | 
						|
                             DAG.getValueType(VA.getValVT()));
 | 
						|
    else if (VA.getLocInfo() == CCValAssign::ZExt)
 | 
						|
      RetValue = DAG.getNode(ISD::AssertZext, dl, VA.getLocVT(), RetValue,
 | 
						|
                             DAG.getValueType(VA.getValVT()));
 | 
						|
 | 
						|
    if (VA.getLocInfo() != CCValAssign::Full)
 | 
						|
      RetValue = DAG.getNode(ISD::TRUNCATE, dl, VA.getValVT(), RetValue);
 | 
						|
 | 
						|
    InVals.push_back(RetValue);
 | 
						|
  }
 | 
						|
 | 
						|
  return Chain;
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
SDValue
 | 
						|
SystemZTargetLowering::LowerReturn(SDValue Chain,
 | 
						|
                                   CallingConv::ID CallConv, bool isVarArg,
 | 
						|
                                   const SmallVectorImpl<ISD::OutputArg> &Outs,
 | 
						|
                                   DebugLoc dl, SelectionDAG &DAG) {
 | 
						|
 | 
						|
  // CCValAssign - represent the assignment of the return value to a location
 | 
						|
  SmallVector<CCValAssign, 16> RVLocs;
 | 
						|
 | 
						|
  // CCState - Info about the registers and stack slot.
 | 
						|
  CCState CCInfo(CallConv, isVarArg, getTargetMachine(),
 | 
						|
                 RVLocs, *DAG.getContext());
 | 
						|
 | 
						|
  // Analize return values.
 | 
						|
  CCInfo.AnalyzeReturn(Outs, RetCC_SystemZ);
 | 
						|
 | 
						|
  // If this is the first return lowered for this function, add the regs to the
 | 
						|
  // liveout set for the function.
 | 
						|
  if (DAG.getMachineFunction().getRegInfo().liveout_empty()) {
 | 
						|
    for (unsigned i = 0; i != RVLocs.size(); ++i)
 | 
						|
      if (RVLocs[i].isRegLoc())
 | 
						|
        DAG.getMachineFunction().getRegInfo().addLiveOut(RVLocs[i].getLocReg());
 | 
						|
  }
 | 
						|
 | 
						|
  SDValue Flag;
 | 
						|
 | 
						|
  // Copy the result values into the output registers.
 | 
						|
  for (unsigned i = 0; i != RVLocs.size(); ++i) {
 | 
						|
    CCValAssign &VA = RVLocs[i];
 | 
						|
    SDValue ResValue = Outs[i].Val;
 | 
						|
    assert(VA.isRegLoc() && "Can only return in registers!");
 | 
						|
 | 
						|
    // If this is an 8/16/32-bit value, it is really should be passed promoted
 | 
						|
    // to 64 bits.
 | 
						|
    if (VA.getLocInfo() == CCValAssign::SExt)
 | 
						|
      ResValue = DAG.getNode(ISD::SIGN_EXTEND, dl, VA.getLocVT(), ResValue);
 | 
						|
    else if (VA.getLocInfo() == CCValAssign::ZExt)
 | 
						|
      ResValue = DAG.getNode(ISD::ZERO_EXTEND, dl, VA.getLocVT(), ResValue);
 | 
						|
    else if (VA.getLocInfo() == CCValAssign::AExt)
 | 
						|
      ResValue = DAG.getNode(ISD::ANY_EXTEND, dl, VA.getLocVT(), ResValue);
 | 
						|
 | 
						|
    Chain = DAG.getCopyToReg(Chain, dl, VA.getLocReg(), ResValue, Flag);
 | 
						|
 | 
						|
    // Guarantee that all emitted copies are stuck together,
 | 
						|
    // avoiding something bad.
 | 
						|
    Flag = Chain.getValue(1);
 | 
						|
  }
 | 
						|
 | 
						|
  if (Flag.getNode())
 | 
						|
    return DAG.getNode(SystemZISD::RET_FLAG, dl, MVT::Other, Chain, Flag);
 | 
						|
 | 
						|
  // Return Void
 | 
						|
  return DAG.getNode(SystemZISD::RET_FLAG, dl, MVT::Other, Chain);
 | 
						|
}
 | 
						|
 | 
						|
SDValue SystemZTargetLowering::EmitCmp(SDValue LHS, SDValue RHS,
 | 
						|
                                       ISD::CondCode CC, SDValue &SystemZCC,
 | 
						|
                                       SelectionDAG &DAG) {
 | 
						|
  // FIXME: Emit a test if RHS is zero
 | 
						|
 | 
						|
  bool isUnsigned = false;
 | 
						|
  SystemZCC::CondCodes TCC;
 | 
						|
  switch (CC) {
 | 
						|
  default:
 | 
						|
    llvm_unreachable("Invalid integer condition!");
 | 
						|
  case ISD::SETEQ:
 | 
						|
  case ISD::SETOEQ:
 | 
						|
    TCC = SystemZCC::E;
 | 
						|
    break;
 | 
						|
  case ISD::SETUEQ:
 | 
						|
    TCC = SystemZCC::NLH;
 | 
						|
    break;
 | 
						|
  case ISD::SETNE:
 | 
						|
  case ISD::SETONE:
 | 
						|
    TCC = SystemZCC::NE;
 | 
						|
    break;
 | 
						|
  case ISD::SETUNE:
 | 
						|
    TCC = SystemZCC::LH;
 | 
						|
    break;
 | 
						|
  case ISD::SETO:
 | 
						|
    TCC = SystemZCC::O;
 | 
						|
    break;
 | 
						|
  case ISD::SETUO:
 | 
						|
    TCC = SystemZCC::NO;
 | 
						|
    break;
 | 
						|
  case ISD::SETULE:
 | 
						|
    if (LHS.getValueType().isFloatingPoint()) {
 | 
						|
      TCC = SystemZCC::NH;
 | 
						|
      break;
 | 
						|
    }
 | 
						|
    isUnsigned = true;   // FALLTHROUGH
 | 
						|
  case ISD::SETLE:
 | 
						|
  case ISD::SETOLE:
 | 
						|
    TCC = SystemZCC::LE;
 | 
						|
    break;
 | 
						|
  case ISD::SETUGE:
 | 
						|
    if (LHS.getValueType().isFloatingPoint()) {
 | 
						|
      TCC = SystemZCC::NL;
 | 
						|
      break;
 | 
						|
    }
 | 
						|
    isUnsigned = true;   // FALLTHROUGH
 | 
						|
  case ISD::SETGE:
 | 
						|
  case ISD::SETOGE:
 | 
						|
    TCC = SystemZCC::HE;
 | 
						|
    break;
 | 
						|
  case ISD::SETUGT:
 | 
						|
    if (LHS.getValueType().isFloatingPoint()) {
 | 
						|
      TCC = SystemZCC::NLE;
 | 
						|
      break;
 | 
						|
    }
 | 
						|
    isUnsigned = true;  // FALLTHROUGH
 | 
						|
  case ISD::SETGT:
 | 
						|
  case ISD::SETOGT:
 | 
						|
    TCC = SystemZCC::H;
 | 
						|
    break;
 | 
						|
  case ISD::SETULT:
 | 
						|
    if (LHS.getValueType().isFloatingPoint()) {
 | 
						|
      TCC = SystemZCC::NHE;
 | 
						|
      break;
 | 
						|
    }
 | 
						|
    isUnsigned = true;  // FALLTHROUGH
 | 
						|
  case ISD::SETLT:
 | 
						|
  case ISD::SETOLT:
 | 
						|
    TCC = SystemZCC::L;
 | 
						|
    break;
 | 
						|
  }
 | 
						|
 | 
						|
  SystemZCC = DAG.getConstant(TCC, MVT::i32);
 | 
						|
 | 
						|
  DebugLoc dl = LHS.getDebugLoc();
 | 
						|
  return DAG.getNode((isUnsigned ? SystemZISD::UCMP : SystemZISD::CMP),
 | 
						|
                     dl, MVT::i64, LHS, RHS);
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
SDValue SystemZTargetLowering::LowerBR_CC(SDValue Op, SelectionDAG &DAG) {
 | 
						|
  SDValue Chain = Op.getOperand(0);
 | 
						|
  ISD::CondCode CC = cast<CondCodeSDNode>(Op.getOperand(1))->get();
 | 
						|
  SDValue LHS   = Op.getOperand(2);
 | 
						|
  SDValue RHS   = Op.getOperand(3);
 | 
						|
  SDValue Dest  = Op.getOperand(4);
 | 
						|
  DebugLoc dl   = Op.getDebugLoc();
 | 
						|
 | 
						|
  SDValue SystemZCC;
 | 
						|
  SDValue Flag = EmitCmp(LHS, RHS, CC, SystemZCC, DAG);
 | 
						|
  return DAG.getNode(SystemZISD::BRCOND, dl, Op.getValueType(),
 | 
						|
                     Chain, Dest, SystemZCC, Flag);
 | 
						|
}
 | 
						|
 | 
						|
SDValue SystemZTargetLowering::LowerSELECT_CC(SDValue Op, SelectionDAG &DAG) {
 | 
						|
  SDValue LHS    = Op.getOperand(0);
 | 
						|
  SDValue RHS    = Op.getOperand(1);
 | 
						|
  SDValue TrueV  = Op.getOperand(2);
 | 
						|
  SDValue FalseV = Op.getOperand(3);
 | 
						|
  ISD::CondCode CC = cast<CondCodeSDNode>(Op.getOperand(4))->get();
 | 
						|
  DebugLoc dl   = Op.getDebugLoc();
 | 
						|
 | 
						|
  SDValue SystemZCC;
 | 
						|
  SDValue Flag = EmitCmp(LHS, RHS, CC, SystemZCC, DAG);
 | 
						|
 | 
						|
  SDVTList VTs = DAG.getVTList(Op.getValueType(), MVT::Flag);
 | 
						|
  SmallVector<SDValue, 4> Ops;
 | 
						|
  Ops.push_back(TrueV);
 | 
						|
  Ops.push_back(FalseV);
 | 
						|
  Ops.push_back(SystemZCC);
 | 
						|
  Ops.push_back(Flag);
 | 
						|
 | 
						|
  return DAG.getNode(SystemZISD::SELECT, dl, VTs, &Ops[0], Ops.size());
 | 
						|
}
 | 
						|
 | 
						|
SDValue SystemZTargetLowering::LowerGlobalAddress(SDValue Op,
 | 
						|
                                                  SelectionDAG &DAG) {
 | 
						|
  DebugLoc dl = Op.getDebugLoc();
 | 
						|
  GlobalValue *GV = cast<GlobalAddressSDNode>(Op)->getGlobal();
 | 
						|
  int64_t Offset = cast<GlobalAddressSDNode>(Op)->getOffset();
 | 
						|
 | 
						|
  bool IsPic = getTargetMachine().getRelocationModel() == Reloc::PIC_;
 | 
						|
  bool ExtraLoadRequired =
 | 
						|
    Subtarget.GVRequiresExtraLoad(GV, getTargetMachine(), false);
 | 
						|
 | 
						|
  SDValue Result;
 | 
						|
  if (!IsPic && !ExtraLoadRequired) {
 | 
						|
    Result = DAG.getTargetGlobalAddress(GV, getPointerTy(), Offset);
 | 
						|
    Offset = 0;
 | 
						|
  } else {
 | 
						|
    unsigned char OpFlags = 0;
 | 
						|
    if (ExtraLoadRequired)
 | 
						|
      OpFlags = SystemZII::MO_GOTENT;
 | 
						|
 | 
						|
    Result = DAG.getTargetGlobalAddress(GV, getPointerTy(), 0, OpFlags);
 | 
						|
  }
 | 
						|
 | 
						|
  Result = DAG.getNode(SystemZISD::PCRelativeWrapper, dl,
 | 
						|
                       getPointerTy(), Result);
 | 
						|
 | 
						|
  if (ExtraLoadRequired)
 | 
						|
    Result = DAG.getLoad(getPointerTy(), dl, DAG.getEntryNode(), Result,
 | 
						|
                         PseudoSourceValue::getGOT(), 0);
 | 
						|
 | 
						|
  // If there was a non-zero offset that we didn't fold, create an explicit
 | 
						|
  // addition for it.
 | 
						|
  if (Offset != 0)
 | 
						|
    Result = DAG.getNode(ISD::ADD, dl, getPointerTy(), Result,
 | 
						|
                         DAG.getConstant(Offset, getPointerTy()));
 | 
						|
 | 
						|
  return Result;
 | 
						|
}
 | 
						|
 | 
						|
// FIXME: PIC here
 | 
						|
SDValue SystemZTargetLowering::LowerJumpTable(SDValue Op,
 | 
						|
                                              SelectionDAG &DAG) {
 | 
						|
  DebugLoc dl = Op.getDebugLoc();
 | 
						|
  JumpTableSDNode *JT = cast<JumpTableSDNode>(Op);
 | 
						|
  SDValue Result = DAG.getTargetJumpTable(JT->getIndex(), getPointerTy());
 | 
						|
 | 
						|
  return DAG.getNode(SystemZISD::PCRelativeWrapper, dl, getPointerTy(), Result);
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
// FIXME: PIC here
 | 
						|
// FIXME: This is just dirty hack. We need to lower cpool properly
 | 
						|
SDValue SystemZTargetLowering::LowerConstantPool(SDValue Op,
 | 
						|
                                                 SelectionDAG &DAG) {
 | 
						|
  DebugLoc dl = Op.getDebugLoc();
 | 
						|
  ConstantPoolSDNode *CP = cast<ConstantPoolSDNode>(Op);
 | 
						|
 | 
						|
  SDValue Result = DAG.getTargetConstantPool(CP->getConstVal(), getPointerTy(),
 | 
						|
                                             CP->getAlignment(),
 | 
						|
                                             CP->getOffset());
 | 
						|
 | 
						|
  return DAG.getNode(SystemZISD::PCRelativeWrapper, dl, getPointerTy(), Result);
 | 
						|
}
 | 
						|
 | 
						|
const char *SystemZTargetLowering::getTargetNodeName(unsigned Opcode) const {
 | 
						|
  switch (Opcode) {
 | 
						|
  case SystemZISD::RET_FLAG:           return "SystemZISD::RET_FLAG";
 | 
						|
  case SystemZISD::CALL:               return "SystemZISD::CALL";
 | 
						|
  case SystemZISD::BRCOND:             return "SystemZISD::BRCOND";
 | 
						|
  case SystemZISD::CMP:                return "SystemZISD::CMP";
 | 
						|
  case SystemZISD::UCMP:               return "SystemZISD::UCMP";
 | 
						|
  case SystemZISD::SELECT:             return "SystemZISD::SELECT";
 | 
						|
  case SystemZISD::PCRelativeWrapper:  return "SystemZISD::PCRelativeWrapper";
 | 
						|
  default: return NULL;
 | 
						|
  }
 | 
						|
}
 | 
						|
 | 
						|
//===----------------------------------------------------------------------===//
 | 
						|
//  Other Lowering Code
 | 
						|
//===----------------------------------------------------------------------===//
 | 
						|
 | 
						|
MachineBasicBlock*
 | 
						|
SystemZTargetLowering::EmitInstrWithCustomInserter(MachineInstr *MI,
 | 
						|
                                                   MachineBasicBlock *BB,
 | 
						|
                   DenseMap<MachineBasicBlock*, MachineBasicBlock*> *EM) const {
 | 
						|
  const SystemZInstrInfo &TII = *TM.getInstrInfo();
 | 
						|
  DebugLoc dl = MI->getDebugLoc();
 | 
						|
  assert((MI->getOpcode() == SystemZ::Select32  ||
 | 
						|
          MI->getOpcode() == SystemZ::SelectF32 ||
 | 
						|
          MI->getOpcode() == SystemZ::Select64  ||
 | 
						|
          MI->getOpcode() == SystemZ::SelectF64) &&
 | 
						|
         "Unexpected instr type to insert");
 | 
						|
 | 
						|
  // To "insert" a SELECT instruction, we actually have to insert the diamond
 | 
						|
  // control-flow pattern.  The incoming instruction knows the destination vreg
 | 
						|
  // to set, the condition code register to branch on, the true/false values to
 | 
						|
  // select between, and a branch opcode to use.
 | 
						|
  const BasicBlock *LLVM_BB = BB->getBasicBlock();
 | 
						|
  MachineFunction::iterator I = BB;
 | 
						|
  ++I;
 | 
						|
 | 
						|
  //  thisMBB:
 | 
						|
  //  ...
 | 
						|
  //   TrueVal = ...
 | 
						|
  //   cmpTY ccX, r1, r2
 | 
						|
  //   jCC copy1MBB
 | 
						|
  //   fallthrough --> copy0MBB
 | 
						|
  MachineBasicBlock *thisMBB = BB;
 | 
						|
  MachineFunction *F = BB->getParent();
 | 
						|
  MachineBasicBlock *copy0MBB = F->CreateMachineBasicBlock(LLVM_BB);
 | 
						|
  MachineBasicBlock *copy1MBB = F->CreateMachineBasicBlock(LLVM_BB);
 | 
						|
  SystemZCC::CondCodes CC = (SystemZCC::CondCodes)MI->getOperand(3).getImm();
 | 
						|
  BuildMI(BB, dl, TII.getBrCond(CC)).addMBB(copy1MBB);
 | 
						|
  F->insert(I, copy0MBB);
 | 
						|
  F->insert(I, copy1MBB);
 | 
						|
  // Inform sdisel of the edge changes.
 | 
						|
  for (MachineBasicBlock::succ_iterator SI = BB->succ_begin(), 
 | 
						|
         SE = BB->succ_end(); SI != SE; ++SI)
 | 
						|
    EM->insert(std::make_pair(*SI, copy1MBB));
 | 
						|
  // Update machine-CFG edges by transferring all successors of the current
 | 
						|
  // block to the new block which will contain the Phi node for the select.
 | 
						|
  copy1MBB->transferSuccessors(BB);
 | 
						|
  // Next, add the true and fallthrough blocks as its successors.
 | 
						|
  BB->addSuccessor(copy0MBB);
 | 
						|
  BB->addSuccessor(copy1MBB);
 | 
						|
 | 
						|
  //  copy0MBB:
 | 
						|
  //   %FalseValue = ...
 | 
						|
  //   # fallthrough to copy1MBB
 | 
						|
  BB = copy0MBB;
 | 
						|
 | 
						|
  // Update machine-CFG edges
 | 
						|
  BB->addSuccessor(copy1MBB);
 | 
						|
 | 
						|
  //  copy1MBB:
 | 
						|
  //   %Result = phi [ %FalseValue, copy0MBB ], [ %TrueValue, thisMBB ]
 | 
						|
  //  ...
 | 
						|
  BB = copy1MBB;
 | 
						|
  BuildMI(BB, dl, TII.get(SystemZ::PHI),
 | 
						|
          MI->getOperand(0).getReg())
 | 
						|
    .addReg(MI->getOperand(2).getReg()).addMBB(copy0MBB)
 | 
						|
    .addReg(MI->getOperand(1).getReg()).addMBB(thisMBB);
 | 
						|
 | 
						|
  F->DeleteMachineInstr(MI);   // The pseudo instruction is gone now.
 | 
						|
  return BB;
 | 
						|
}
 |