mirror of
https://github.com/c64scene-ar/llvm-6502.git
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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@45605 91177308-0d34-0410-b5e6-96231b3b80d8
1548 lines
54 KiB
C++
1548 lines
54 KiB
C++
//===- X86ISelDAGToDAG.cpp - A DAG pattern matching inst selector for X86 -===//
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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 a DAG pattern matching instruction selector for X86,
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// converting from a legalized dag to a X86 dag.
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//
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//===----------------------------------------------------------------------===//
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#define DEBUG_TYPE "x86-isel"
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#include "X86.h"
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#include "X86InstrBuilder.h"
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#include "X86ISelLowering.h"
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#include "X86MachineFunctionInfo.h"
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#include "X86RegisterInfo.h"
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#include "X86Subtarget.h"
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#include "X86TargetMachine.h"
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#include "llvm/GlobalValue.h"
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#include "llvm/Instructions.h"
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#include "llvm/Intrinsics.h"
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#include "llvm/Support/CFG.h"
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#include "llvm/Type.h"
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#include "llvm/CodeGen/MachineConstantPool.h"
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#include "llvm/CodeGen/MachineFunction.h"
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#include "llvm/CodeGen/MachineFrameInfo.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/SelectionDAGISel.h"
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#include "llvm/Target/TargetMachine.h"
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#include "llvm/Support/Compiler.h"
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#include "llvm/Support/Debug.h"
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#include "llvm/Support/MathExtras.h"
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#include "llvm/ADT/Statistic.h"
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#include <queue>
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#include <set>
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using namespace llvm;
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STATISTIC(NumFPKill , "Number of FP_REG_KILL instructions added");
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STATISTIC(NumLoadMoved, "Number of loads moved below TokenFactor");
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//===----------------------------------------------------------------------===//
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// Pattern Matcher Implementation
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//===----------------------------------------------------------------------===//
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namespace {
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/// X86ISelAddressMode - This corresponds to X86AddressMode, but uses
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/// SDOperand's instead of register numbers for the leaves of the matched
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/// tree.
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struct X86ISelAddressMode {
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enum {
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RegBase,
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FrameIndexBase
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} BaseType;
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struct { // This is really a union, discriminated by BaseType!
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SDOperand Reg;
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int FrameIndex;
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} Base;
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bool isRIPRel; // RIP relative?
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unsigned Scale;
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SDOperand IndexReg;
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unsigned Disp;
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GlobalValue *GV;
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Constant *CP;
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const char *ES;
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int JT;
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unsigned Align; // CP alignment.
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X86ISelAddressMode()
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: BaseType(RegBase), isRIPRel(false), Scale(1), IndexReg(), Disp(0),
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GV(0), CP(0), ES(0), JT(-1), Align(0) {
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}
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};
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}
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namespace {
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//===--------------------------------------------------------------------===//
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/// ISel - X86 specific code to select X86 machine instructions for
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/// SelectionDAG operations.
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///
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class VISIBILITY_HIDDEN X86DAGToDAGISel : public SelectionDAGISel {
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/// ContainsFPCode - Every instruction we select that uses or defines a FP
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/// register should set this to true.
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bool ContainsFPCode;
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/// FastISel - Enable fast(er) instruction selection.
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///
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bool FastISel;
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/// TM - Keep a reference to X86TargetMachine.
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///
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X86TargetMachine &TM;
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/// X86Lowering - This object fully describes how to lower LLVM code to an
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/// X86-specific SelectionDAG.
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X86TargetLowering X86Lowering;
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/// Subtarget - Keep a pointer to the X86Subtarget around so that we can
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/// make the right decision when generating code for different targets.
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const X86Subtarget *Subtarget;
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/// GlobalBaseReg - keeps track of the virtual register mapped onto global
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/// base register.
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unsigned GlobalBaseReg;
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public:
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X86DAGToDAGISel(X86TargetMachine &tm, bool fast)
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: SelectionDAGISel(X86Lowering),
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ContainsFPCode(false), FastISel(fast), TM(tm),
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X86Lowering(*TM.getTargetLowering()),
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Subtarget(&TM.getSubtarget<X86Subtarget>()) {}
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virtual bool runOnFunction(Function &Fn) {
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// Make sure we re-emit a set of the global base reg if necessary
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GlobalBaseReg = 0;
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return SelectionDAGISel::runOnFunction(Fn);
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}
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virtual const char *getPassName() const {
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return "X86 DAG->DAG Instruction Selection";
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}
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/// InstructionSelectBasicBlock - This callback is invoked by
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/// SelectionDAGISel when it has created a SelectionDAG for us to codegen.
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virtual void InstructionSelectBasicBlock(SelectionDAG &DAG);
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virtual void EmitFunctionEntryCode(Function &Fn, MachineFunction &MF);
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virtual bool CanBeFoldedBy(SDNode *N, SDNode *U, SDNode *Root) const;
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// Include the pieces autogenerated from the target description.
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#include "X86GenDAGISel.inc"
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private:
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SDNode *Select(SDOperand N);
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bool MatchAddress(SDOperand N, X86ISelAddressMode &AM,
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bool isRoot = true, unsigned Depth = 0);
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bool MatchAddressBase(SDOperand N, X86ISelAddressMode &AM,
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bool isRoot, unsigned Depth);
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bool SelectAddr(SDOperand Op, SDOperand N, SDOperand &Base,
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SDOperand &Scale, SDOperand &Index, SDOperand &Disp);
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bool SelectLEAAddr(SDOperand Op, SDOperand N, SDOperand &Base,
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SDOperand &Scale, SDOperand &Index, SDOperand &Disp);
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bool SelectScalarSSELoad(SDOperand Op, SDOperand Pred,
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SDOperand N, SDOperand &Base, SDOperand &Scale,
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SDOperand &Index, SDOperand &Disp,
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SDOperand &InChain, SDOperand &OutChain);
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bool TryFoldLoad(SDOperand P, SDOperand N,
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SDOperand &Base, SDOperand &Scale,
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SDOperand &Index, SDOperand &Disp);
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void InstructionSelectPreprocess(SelectionDAG &DAG);
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/// SelectInlineAsmMemoryOperand - Implement addressing mode selection for
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/// inline asm expressions.
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virtual bool SelectInlineAsmMemoryOperand(const SDOperand &Op,
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char ConstraintCode,
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std::vector<SDOperand> &OutOps,
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SelectionDAG &DAG);
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void EmitSpecialCodeForMain(MachineBasicBlock *BB, MachineFrameInfo *MFI);
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inline void getAddressOperands(X86ISelAddressMode &AM, SDOperand &Base,
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SDOperand &Scale, SDOperand &Index,
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SDOperand &Disp) {
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Base = (AM.BaseType == X86ISelAddressMode::FrameIndexBase) ?
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CurDAG->getTargetFrameIndex(AM.Base.FrameIndex, TLI.getPointerTy()) :
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AM.Base.Reg;
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Scale = getI8Imm(AM.Scale);
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Index = AM.IndexReg;
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// These are 32-bit even in 64-bit mode since RIP relative offset
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// is 32-bit.
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if (AM.GV)
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Disp = CurDAG->getTargetGlobalAddress(AM.GV, MVT::i32, AM.Disp);
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else if (AM.CP)
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Disp = CurDAG->getTargetConstantPool(AM.CP, MVT::i32, AM.Align, AM.Disp);
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else if (AM.ES)
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Disp = CurDAG->getTargetExternalSymbol(AM.ES, MVT::i32);
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else if (AM.JT != -1)
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Disp = CurDAG->getTargetJumpTable(AM.JT, MVT::i32);
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else
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Disp = getI32Imm(AM.Disp);
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}
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/// getI8Imm - Return a target constant with the specified value, of type
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/// i8.
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inline SDOperand getI8Imm(unsigned Imm) {
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return CurDAG->getTargetConstant(Imm, MVT::i8);
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}
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/// getI16Imm - Return a target constant with the specified value, of type
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/// i16.
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inline SDOperand getI16Imm(unsigned Imm) {
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return CurDAG->getTargetConstant(Imm, MVT::i16);
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}
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/// getI32Imm - Return a target constant with the specified value, of type
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/// i32.
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inline SDOperand getI32Imm(unsigned Imm) {
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return CurDAG->getTargetConstant(Imm, MVT::i32);
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}
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/// getGlobalBaseReg - insert code into the entry mbb to materialize the PIC
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/// base register. Return the virtual register that holds this value.
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SDNode *getGlobalBaseReg();
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/// getTruncate - return an SDNode that implements a subreg based truncate
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/// of the specified operand to the the specified value type.
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SDNode *getTruncate(SDOperand N0, MVT::ValueType VT);
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#ifndef NDEBUG
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unsigned Indent;
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#endif
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};
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}
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static SDNode *findFlagUse(SDNode *N) {
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unsigned FlagResNo = N->getNumValues()-1;
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for (SDNode::use_iterator I = N->use_begin(), E = N->use_end(); I != E; ++I) {
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SDNode *User = *I;
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for (unsigned i = 0, e = User->getNumOperands(); i != e; ++i) {
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SDOperand Op = User->getOperand(i);
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if (Op.Val == N && Op.ResNo == FlagResNo)
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return User;
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}
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}
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return NULL;
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}
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static void findNonImmUse(SDNode *Use, SDNode* Def, SDNode *ImmedUse,
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SDNode *Root, SDNode *Skip, bool &found,
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std::set<SDNode *> &Visited) {
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if (found ||
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Use->getNodeId() > Def->getNodeId() ||
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!Visited.insert(Use).second)
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return;
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for (unsigned i = 0, e = Use->getNumOperands(); !found && i != e; ++i) {
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SDNode *N = Use->getOperand(i).Val;
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if (N == Skip)
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continue;
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if (N == Def) {
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if (Use == ImmedUse)
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continue; // Immediate use is ok.
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if (Use == Root) {
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assert(Use->getOpcode() == ISD::STORE ||
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Use->getOpcode() == X86ISD::CMP);
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continue;
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}
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found = true;
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break;
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}
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findNonImmUse(N, Def, ImmedUse, Root, Skip, found, Visited);
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}
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}
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/// isNonImmUse - Start searching from Root up the DAG to check is Def can
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/// be reached. Return true if that's the case. However, ignore direct uses
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/// by ImmedUse (which would be U in the example illustrated in
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/// CanBeFoldedBy) and by Root (which can happen in the store case).
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/// FIXME: to be really generic, we should allow direct use by any node
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/// that is being folded. But realisticly since we only fold loads which
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/// have one non-chain use, we only need to watch out for load/op/store
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/// and load/op/cmp case where the root (store / cmp) may reach the load via
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/// its chain operand.
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static inline bool isNonImmUse(SDNode *Root, SDNode *Def, SDNode *ImmedUse,
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SDNode *Skip = NULL) {
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std::set<SDNode *> Visited;
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bool found = false;
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findNonImmUse(Root, Def, ImmedUse, Root, Skip, found, Visited);
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return found;
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}
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bool X86DAGToDAGISel::CanBeFoldedBy(SDNode *N, SDNode *U, SDNode *Root) const {
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if (FastISel) return false;
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// If U use can somehow reach N through another path then U can't fold N or
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// it will create a cycle. e.g. In the following diagram, U can reach N
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// through X. If N is folded into into U, then X is both a predecessor and
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// a successor of U.
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//
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// [ N ]
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// ^ ^
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// | |
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// / \---
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// / [X]
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// | ^
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// [U]--------|
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if (isNonImmUse(Root, N, U))
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return false;
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// If U produces a flag, then it gets (even more) interesting. Since it
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// would have been "glued" together with its flag use, we need to check if
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// it might reach N:
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//
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// [ N ]
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// ^ ^
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// | |
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// [U] \--
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// ^ [TF]
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// | ^
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// | |
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// \ /
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// [FU]
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//
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// If FU (flag use) indirectly reach N (the load), and U fold N (call it
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// NU), then TF is a predecessor of FU and a successor of NU. But since
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// NU and FU are flagged together, this effectively creates a cycle.
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bool HasFlagUse = false;
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MVT::ValueType VT = Root->getValueType(Root->getNumValues()-1);
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while ((VT == MVT::Flag && !Root->use_empty())) {
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SDNode *FU = findFlagUse(Root);
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if (FU == NULL)
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break;
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else {
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Root = FU;
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HasFlagUse = true;
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}
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VT = Root->getValueType(Root->getNumValues()-1);
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}
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if (HasFlagUse)
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return !isNonImmUse(Root, N, Root, U);
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return true;
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}
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/// MoveBelowTokenFactor - Replace TokenFactor operand with load's chain operand
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/// and move load below the TokenFactor. Replace store's chain operand with
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/// load's chain result.
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static void MoveBelowTokenFactor(SelectionDAG &DAG, SDOperand Load,
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SDOperand Store, SDOperand TF) {
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std::vector<SDOperand> Ops;
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for (unsigned i = 0, e = TF.Val->getNumOperands(); i != e; ++i)
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if (Load.Val == TF.Val->getOperand(i).Val)
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Ops.push_back(Load.Val->getOperand(0));
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else
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Ops.push_back(TF.Val->getOperand(i));
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DAG.UpdateNodeOperands(TF, &Ops[0], Ops.size());
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DAG.UpdateNodeOperands(Load, TF, Load.getOperand(1), Load.getOperand(2));
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DAG.UpdateNodeOperands(Store, Load.getValue(1), Store.getOperand(1),
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Store.getOperand(2), Store.getOperand(3));
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}
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/// InstructionSelectPreprocess - Preprocess the DAG to allow the instruction
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/// selector to pick more load-modify-store instructions. This is a common
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/// case:
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///
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/// [Load chain]
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/// ^
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/// |
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/// [Load]
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/// ^ ^
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/// | |
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/// / \-
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/// / |
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/// [TokenFactor] [Op]
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/// ^ ^
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/// | |
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/// \ /
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/// \ /
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/// [Store]
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///
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/// The fact the store's chain operand != load's chain will prevent the
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/// (store (op (load))) instruction from being selected. We can transform it to:
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///
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/// [Load chain]
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/// ^
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/// |
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/// [TokenFactor]
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/// ^
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/// |
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/// [Load]
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/// ^ ^
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/// | |
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/// | \-
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/// | |
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/// | [Op]
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/// | ^
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/// | |
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/// \ /
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/// \ /
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/// [Store]
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void X86DAGToDAGISel::InstructionSelectPreprocess(SelectionDAG &DAG) {
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for (SelectionDAG::allnodes_iterator I = DAG.allnodes_begin(),
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E = DAG.allnodes_end(); I != E; ++I) {
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if (!ISD::isNON_TRUNCStore(I))
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continue;
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SDOperand Chain = I->getOperand(0);
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if (Chain.Val->getOpcode() != ISD::TokenFactor)
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continue;
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SDOperand N1 = I->getOperand(1);
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SDOperand N2 = I->getOperand(2);
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if (MVT::isFloatingPoint(N1.getValueType()) ||
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MVT::isVector(N1.getValueType()) ||
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!N1.hasOneUse())
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continue;
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bool RModW = false;
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SDOperand Load;
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unsigned Opcode = N1.Val->getOpcode();
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switch (Opcode) {
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case ISD::ADD:
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case ISD::MUL:
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case ISD::AND:
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case ISD::OR:
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case ISD::XOR:
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case ISD::ADDC:
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case ISD::ADDE: {
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SDOperand N10 = N1.getOperand(0);
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SDOperand N11 = N1.getOperand(1);
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if (ISD::isNON_EXTLoad(N10.Val))
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RModW = true;
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else if (ISD::isNON_EXTLoad(N11.Val)) {
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RModW = true;
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std::swap(N10, N11);
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}
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RModW = RModW && N10.Val->isOperand(Chain.Val) && N10.hasOneUse() &&
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(N10.getOperand(1) == N2) &&
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(N10.Val->getValueType(0) == N1.getValueType());
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if (RModW)
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Load = N10;
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break;
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}
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case ISD::SUB:
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case ISD::SHL:
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case ISD::SRA:
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case ISD::SRL:
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case ISD::ROTL:
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case ISD::ROTR:
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case ISD::SUBC:
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case ISD::SUBE:
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case X86ISD::SHLD:
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case X86ISD::SHRD: {
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SDOperand N10 = N1.getOperand(0);
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if (ISD::isNON_EXTLoad(N10.Val))
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RModW = N10.Val->isOperand(Chain.Val) && N10.hasOneUse() &&
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(N10.getOperand(1) == N2) &&
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(N10.Val->getValueType(0) == N1.getValueType());
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if (RModW)
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Load = N10;
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break;
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}
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}
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if (RModW) {
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MoveBelowTokenFactor(DAG, Load, SDOperand(I, 0), Chain);
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++NumLoadMoved;
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}
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}
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}
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/// InstructionSelectBasicBlock - This callback is invoked by SelectionDAGISel
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/// when it has created a SelectionDAG for us to codegen.
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void X86DAGToDAGISel::InstructionSelectBasicBlock(SelectionDAG &DAG) {
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DEBUG(BB->dump());
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MachineFunction::iterator FirstMBB = BB;
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if (!FastISel)
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InstructionSelectPreprocess(DAG);
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// Codegen the basic block.
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#ifndef NDEBUG
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DOUT << "===== Instruction selection begins:\n";
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Indent = 0;
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#endif
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DAG.setRoot(SelectRoot(DAG.getRoot()));
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#ifndef NDEBUG
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DOUT << "===== Instruction selection ends:\n";
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#endif
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DAG.RemoveDeadNodes();
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// Emit machine code to BB.
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ScheduleAndEmitDAG(DAG);
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// If we are emitting FP stack code, scan the basic block to determine if this
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|
// block defines any FP values. If so, put an FP_REG_KILL instruction before
|
|
// the terminator of the block.
|
|
|
|
// Note that FP stack instructions are used in all modes for long double,
|
|
// so we always need to do this check.
|
|
// Also note that it's possible for an FP stack register to be live across
|
|
// an instruction that produces multiple basic blocks (SSE CMOV) so we
|
|
// must check all the generated basic blocks.
|
|
|
|
// Scan all of the machine instructions in these MBBs, checking for FP
|
|
// stores. (RFP32 and RFP64 will not exist in SSE mode, but RFP80 might.)
|
|
MachineFunction::iterator MBBI = FirstMBB;
|
|
do {
|
|
bool ContainsFPCode = false;
|
|
for (MachineBasicBlock::iterator I = MBBI->begin(), E = MBBI->end();
|
|
!ContainsFPCode && I != E; ++I) {
|
|
if (I->getNumOperands() != 0 && I->getOperand(0).isRegister()) {
|
|
const TargetRegisterClass *clas;
|
|
for (unsigned op = 0, e = I->getNumOperands(); op != e; ++op) {
|
|
if (I->getOperand(op).isRegister() && I->getOperand(op).isDef() &&
|
|
MRegisterInfo::isVirtualRegister(I->getOperand(op).getReg()) &&
|
|
((clas = RegInfo->getRegClass(I->getOperand(0).getReg())) ==
|
|
X86::RFP32RegisterClass ||
|
|
clas == X86::RFP64RegisterClass ||
|
|
clas == X86::RFP80RegisterClass)) {
|
|
ContainsFPCode = true;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
// Check PHI nodes in successor blocks. These PHI's will be lowered to have
|
|
// a copy of the input value in this block. In SSE mode, we only care about
|
|
// 80-bit values.
|
|
if (!ContainsFPCode) {
|
|
// Final check, check LLVM BB's that are successors to the LLVM BB
|
|
// corresponding to BB for FP PHI nodes.
|
|
const BasicBlock *LLVMBB = BB->getBasicBlock();
|
|
const PHINode *PN;
|
|
for (succ_const_iterator SI = succ_begin(LLVMBB), E = succ_end(LLVMBB);
|
|
!ContainsFPCode && SI != E; ++SI) {
|
|
for (BasicBlock::const_iterator II = SI->begin();
|
|
(PN = dyn_cast<PHINode>(II)); ++II) {
|
|
if (PN->getType()==Type::X86_FP80Ty ||
|
|
(!Subtarget->hasSSE1() && PN->getType()->isFloatingPoint()) ||
|
|
(!Subtarget->hasSSE2() && PN->getType()==Type::DoubleTy)) {
|
|
ContainsFPCode = true;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
// Finally, if we found any FP code, emit the FP_REG_KILL instruction.
|
|
if (ContainsFPCode) {
|
|
BuildMI(*MBBI, MBBI->getFirstTerminator(),
|
|
TM.getInstrInfo()->get(X86::FP_REG_KILL));
|
|
++NumFPKill;
|
|
}
|
|
} while (&*(MBBI++) != BB);
|
|
}
|
|
|
|
/// EmitSpecialCodeForMain - Emit any code that needs to be executed only in
|
|
/// the main function.
|
|
void X86DAGToDAGISel::EmitSpecialCodeForMain(MachineBasicBlock *BB,
|
|
MachineFrameInfo *MFI) {
|
|
const TargetInstrInfo *TII = TM.getInstrInfo();
|
|
if (Subtarget->isTargetCygMing())
|
|
BuildMI(BB, TII->get(X86::CALLpcrel32)).addExternalSymbol("__main");
|
|
}
|
|
|
|
void X86DAGToDAGISel::EmitFunctionEntryCode(Function &Fn, MachineFunction &MF) {
|
|
// If this is main, emit special code for main.
|
|
MachineBasicBlock *BB = MF.begin();
|
|
if (Fn.hasExternalLinkage() && Fn.getName() == "main")
|
|
EmitSpecialCodeForMain(BB, MF.getFrameInfo());
|
|
}
|
|
|
|
/// MatchAddress - Add the specified node to the specified addressing mode,
|
|
/// returning true if it cannot be done. This just pattern matches for the
|
|
/// addressing mode.
|
|
bool X86DAGToDAGISel::MatchAddress(SDOperand N, X86ISelAddressMode &AM,
|
|
bool isRoot, unsigned Depth) {
|
|
// Limit recursion.
|
|
if (Depth > 5)
|
|
return MatchAddressBase(N, AM, isRoot, Depth);
|
|
|
|
// RIP relative addressing: %rip + 32-bit displacement!
|
|
if (AM.isRIPRel) {
|
|
if (!AM.ES && AM.JT != -1 && N.getOpcode() == ISD::Constant) {
|
|
int64_t Val = cast<ConstantSDNode>(N)->getSignExtended();
|
|
if (isInt32(AM.Disp + Val)) {
|
|
AM.Disp += Val;
|
|
return false;
|
|
}
|
|
}
|
|
return true;
|
|
}
|
|
|
|
int id = N.Val->getNodeId();
|
|
bool AlreadySelected = isSelected(id); // Already selected, not yet replaced.
|
|
|
|
switch (N.getOpcode()) {
|
|
default: break;
|
|
case ISD::Constant: {
|
|
int64_t Val = cast<ConstantSDNode>(N)->getSignExtended();
|
|
if (isInt32(AM.Disp + Val)) {
|
|
AM.Disp += Val;
|
|
return false;
|
|
}
|
|
break;
|
|
}
|
|
|
|
case X86ISD::Wrapper: {
|
|
bool is64Bit = Subtarget->is64Bit();
|
|
// Under X86-64 non-small code model, GV (and friends) are 64-bits.
|
|
if (is64Bit && TM.getCodeModel() != CodeModel::Small)
|
|
break;
|
|
if (AM.GV != 0 || AM.CP != 0 || AM.ES != 0 || AM.JT != -1)
|
|
break;
|
|
// If value is available in a register both base and index components have
|
|
// been picked, we can't fit the result available in the register in the
|
|
// addressing mode. Duplicate GlobalAddress or ConstantPool as displacement.
|
|
if (!AlreadySelected || (AM.Base.Reg.Val && AM.IndexReg.Val)) {
|
|
bool isStatic = TM.getRelocationModel() == Reloc::Static;
|
|
SDOperand N0 = N.getOperand(0);
|
|
// Mac OS X X86-64 lower 4G address is not available.
|
|
bool isAbs32 = !is64Bit ||
|
|
(isStatic && Subtarget->hasLow4GUserSpaceAddress());
|
|
if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(N0)) {
|
|
GlobalValue *GV = G->getGlobal();
|
|
if (isAbs32 || isRoot) {
|
|
AM.GV = GV;
|
|
AM.Disp += G->getOffset();
|
|
AM.isRIPRel = !isAbs32;
|
|
return false;
|
|
}
|
|
} else if (ConstantPoolSDNode *CP = dyn_cast<ConstantPoolSDNode>(N0)) {
|
|
if (isAbs32 || isRoot) {
|
|
AM.CP = CP->getConstVal();
|
|
AM.Align = CP->getAlignment();
|
|
AM.Disp += CP->getOffset();
|
|
AM.isRIPRel = !isAbs32;
|
|
return false;
|
|
}
|
|
} else if (ExternalSymbolSDNode *S =dyn_cast<ExternalSymbolSDNode>(N0)) {
|
|
if (isAbs32 || isRoot) {
|
|
AM.ES = S->getSymbol();
|
|
AM.isRIPRel = !isAbs32;
|
|
return false;
|
|
}
|
|
} else if (JumpTableSDNode *J = dyn_cast<JumpTableSDNode>(N0)) {
|
|
if (isAbs32 || isRoot) {
|
|
AM.JT = J->getIndex();
|
|
AM.isRIPRel = !isAbs32;
|
|
return false;
|
|
}
|
|
}
|
|
}
|
|
break;
|
|
}
|
|
|
|
case ISD::FrameIndex:
|
|
if (AM.BaseType == X86ISelAddressMode::RegBase && AM.Base.Reg.Val == 0) {
|
|
AM.BaseType = X86ISelAddressMode::FrameIndexBase;
|
|
AM.Base.FrameIndex = cast<FrameIndexSDNode>(N)->getIndex();
|
|
return false;
|
|
}
|
|
break;
|
|
|
|
case ISD::SHL:
|
|
if (AlreadySelected || AM.IndexReg.Val != 0 || AM.Scale != 1)
|
|
break;
|
|
|
|
if (ConstantSDNode *CN = dyn_cast<ConstantSDNode>(N.Val->getOperand(1))) {
|
|
unsigned Val = CN->getValue();
|
|
if (Val == 1 || Val == 2 || Val == 3) {
|
|
AM.Scale = 1 << Val;
|
|
SDOperand ShVal = N.Val->getOperand(0);
|
|
|
|
// Okay, we know that we have a scale by now. However, if the scaled
|
|
// value is an add of something and a constant, we can fold the
|
|
// constant into the disp field here.
|
|
if (ShVal.Val->getOpcode() == ISD::ADD && ShVal.hasOneUse() &&
|
|
isa<ConstantSDNode>(ShVal.Val->getOperand(1))) {
|
|
AM.IndexReg = ShVal.Val->getOperand(0);
|
|
ConstantSDNode *AddVal =
|
|
cast<ConstantSDNode>(ShVal.Val->getOperand(1));
|
|
uint64_t Disp = AM.Disp + (AddVal->getValue() << Val);
|
|
if (isInt32(Disp))
|
|
AM.Disp = Disp;
|
|
else
|
|
AM.IndexReg = ShVal;
|
|
} else {
|
|
AM.IndexReg = ShVal;
|
|
}
|
|
return false;
|
|
}
|
|
break;
|
|
}
|
|
|
|
case ISD::SMUL_LOHI:
|
|
case ISD::UMUL_LOHI:
|
|
// A mul_lohi where we need the low part can be folded as a plain multiply.
|
|
if (N.ResNo != 0) break;
|
|
// FALL THROUGH
|
|
case ISD::MUL:
|
|
// X*[3,5,9] -> X+X*[2,4,8]
|
|
if (!AlreadySelected &&
|
|
AM.BaseType == X86ISelAddressMode::RegBase &&
|
|
AM.Base.Reg.Val == 0 &&
|
|
AM.IndexReg.Val == 0) {
|
|
if (ConstantSDNode *CN = dyn_cast<ConstantSDNode>(N.Val->getOperand(1)))
|
|
if (CN->getValue() == 3 || CN->getValue() == 5 || CN->getValue() == 9) {
|
|
AM.Scale = unsigned(CN->getValue())-1;
|
|
|
|
SDOperand MulVal = N.Val->getOperand(0);
|
|
SDOperand Reg;
|
|
|
|
// Okay, we know that we have a scale by now. However, if the scaled
|
|
// value is an add of something and a constant, we can fold the
|
|
// constant into the disp field here.
|
|
if (MulVal.Val->getOpcode() == ISD::ADD && MulVal.hasOneUse() &&
|
|
isa<ConstantSDNode>(MulVal.Val->getOperand(1))) {
|
|
Reg = MulVal.Val->getOperand(0);
|
|
ConstantSDNode *AddVal =
|
|
cast<ConstantSDNode>(MulVal.Val->getOperand(1));
|
|
uint64_t Disp = AM.Disp + AddVal->getValue() * CN->getValue();
|
|
if (isInt32(Disp))
|
|
AM.Disp = Disp;
|
|
else
|
|
Reg = N.Val->getOperand(0);
|
|
} else {
|
|
Reg = N.Val->getOperand(0);
|
|
}
|
|
|
|
AM.IndexReg = AM.Base.Reg = Reg;
|
|
return false;
|
|
}
|
|
}
|
|
break;
|
|
|
|
case ISD::ADD:
|
|
if (!AlreadySelected) {
|
|
X86ISelAddressMode Backup = AM;
|
|
if (!MatchAddress(N.Val->getOperand(0), AM, false, Depth+1) &&
|
|
!MatchAddress(N.Val->getOperand(1), AM, false, Depth+1))
|
|
return false;
|
|
AM = Backup;
|
|
if (!MatchAddress(N.Val->getOperand(1), AM, false, Depth+1) &&
|
|
!MatchAddress(N.Val->getOperand(0), AM, false, Depth+1))
|
|
return false;
|
|
AM = Backup;
|
|
}
|
|
break;
|
|
|
|
case ISD::OR:
|
|
// Handle "X | C" as "X + C" iff X is known to have C bits clear.
|
|
if (AlreadySelected) break;
|
|
|
|
if (ConstantSDNode *CN = dyn_cast<ConstantSDNode>(N.getOperand(1))) {
|
|
X86ISelAddressMode Backup = AM;
|
|
// Start with the LHS as an addr mode.
|
|
if (!MatchAddress(N.getOperand(0), AM, false) &&
|
|
// Address could not have picked a GV address for the displacement.
|
|
AM.GV == NULL &&
|
|
// On x86-64, the resultant disp must fit in 32-bits.
|
|
isInt32(AM.Disp + CN->getSignExtended()) &&
|
|
// Check to see if the LHS & C is zero.
|
|
CurDAG->MaskedValueIsZero(N.getOperand(0), CN->getValue())) {
|
|
AM.Disp += CN->getValue();
|
|
return false;
|
|
}
|
|
AM = Backup;
|
|
}
|
|
break;
|
|
|
|
case ISD::AND: {
|
|
// Handle "(x << C1) & C2" as "(X & (C2>>C1)) << C1" if safe and if this
|
|
// allows us to fold the shift into this addressing mode.
|
|
if (AlreadySelected) break;
|
|
SDOperand Shift = N.getOperand(0);
|
|
if (Shift.getOpcode() != ISD::SHL) break;
|
|
|
|
// Scale must not be used already.
|
|
if (AM.IndexReg.Val != 0 || AM.Scale != 1) break;
|
|
|
|
ConstantSDNode *C2 = dyn_cast<ConstantSDNode>(N.getOperand(1));
|
|
ConstantSDNode *C1 = dyn_cast<ConstantSDNode>(Shift.getOperand(1));
|
|
if (!C1 || !C2) break;
|
|
|
|
// Not likely to be profitable if either the AND or SHIFT node has more
|
|
// than one use (unless all uses are for address computation). Besides,
|
|
// isel mechanism requires their node ids to be reused.
|
|
if (!N.hasOneUse() || !Shift.hasOneUse())
|
|
break;
|
|
|
|
// Verify that the shift amount is something we can fold.
|
|
unsigned ShiftCst = C1->getValue();
|
|
if (ShiftCst != 1 && ShiftCst != 2 && ShiftCst != 3)
|
|
break;
|
|
|
|
// Get the new AND mask, this folds to a constant.
|
|
SDOperand NewANDMask = CurDAG->getNode(ISD::SRL, N.getValueType(),
|
|
SDOperand(C2, 0), SDOperand(C1, 0));
|
|
SDOperand NewAND = CurDAG->getNode(ISD::AND, N.getValueType(),
|
|
Shift.getOperand(0), NewANDMask);
|
|
NewANDMask.Val->setNodeId(Shift.Val->getNodeId());
|
|
NewAND.Val->setNodeId(N.Val->getNodeId());
|
|
|
|
AM.Scale = 1 << ShiftCst;
|
|
AM.IndexReg = NewAND;
|
|
return false;
|
|
}
|
|
}
|
|
|
|
return MatchAddressBase(N, AM, isRoot, Depth);
|
|
}
|
|
|
|
/// MatchAddressBase - Helper for MatchAddress. Add the specified node to the
|
|
/// specified addressing mode without any further recursion.
|
|
bool X86DAGToDAGISel::MatchAddressBase(SDOperand N, X86ISelAddressMode &AM,
|
|
bool isRoot, unsigned Depth) {
|
|
// Is the base register already occupied?
|
|
if (AM.BaseType != X86ISelAddressMode::RegBase || AM.Base.Reg.Val) {
|
|
// If so, check to see if the scale index register is set.
|
|
if (AM.IndexReg.Val == 0) {
|
|
AM.IndexReg = N;
|
|
AM.Scale = 1;
|
|
return false;
|
|
}
|
|
|
|
// Otherwise, we cannot select it.
|
|
return true;
|
|
}
|
|
|
|
// Default, generate it as a register.
|
|
AM.BaseType = X86ISelAddressMode::RegBase;
|
|
AM.Base.Reg = N;
|
|
return false;
|
|
}
|
|
|
|
/// SelectAddr - returns true if it is able pattern match an addressing mode.
|
|
/// It returns the operands which make up the maximal addressing mode it can
|
|
/// match by reference.
|
|
bool X86DAGToDAGISel::SelectAddr(SDOperand Op, SDOperand N, SDOperand &Base,
|
|
SDOperand &Scale, SDOperand &Index,
|
|
SDOperand &Disp) {
|
|
X86ISelAddressMode AM;
|
|
if (MatchAddress(N, AM))
|
|
return false;
|
|
|
|
MVT::ValueType VT = N.getValueType();
|
|
if (AM.BaseType == X86ISelAddressMode::RegBase) {
|
|
if (!AM.Base.Reg.Val)
|
|
AM.Base.Reg = CurDAG->getRegister(0, VT);
|
|
}
|
|
|
|
if (!AM.IndexReg.Val)
|
|
AM.IndexReg = CurDAG->getRegister(0, VT);
|
|
|
|
getAddressOperands(AM, Base, Scale, Index, Disp);
|
|
return true;
|
|
}
|
|
|
|
/// isZeroNode - Returns true if Elt is a constant zero or a floating point
|
|
/// constant +0.0.
|
|
static inline bool isZeroNode(SDOperand Elt) {
|
|
return ((isa<ConstantSDNode>(Elt) &&
|
|
cast<ConstantSDNode>(Elt)->getValue() == 0) ||
|
|
(isa<ConstantFPSDNode>(Elt) &&
|
|
cast<ConstantFPSDNode>(Elt)->getValueAPF().isPosZero()));
|
|
}
|
|
|
|
|
|
/// SelectScalarSSELoad - Match a scalar SSE load. In particular, we want to
|
|
/// match a load whose top elements are either undef or zeros. The load flavor
|
|
/// is derived from the type of N, which is either v4f32 or v2f64.
|
|
bool X86DAGToDAGISel::SelectScalarSSELoad(SDOperand Op, SDOperand Pred,
|
|
SDOperand N, SDOperand &Base,
|
|
SDOperand &Scale, SDOperand &Index,
|
|
SDOperand &Disp, SDOperand &InChain,
|
|
SDOperand &OutChain) {
|
|
if (N.getOpcode() == ISD::SCALAR_TO_VECTOR) {
|
|
InChain = N.getOperand(0).getValue(1);
|
|
if (ISD::isNON_EXTLoad(InChain.Val) &&
|
|
InChain.getValue(0).hasOneUse() &&
|
|
N.hasOneUse() &&
|
|
CanBeFoldedBy(N.Val, Pred.Val, Op.Val)) {
|
|
LoadSDNode *LD = cast<LoadSDNode>(InChain);
|
|
if (!SelectAddr(Op, LD->getBasePtr(), Base, Scale, Index, Disp))
|
|
return false;
|
|
OutChain = LD->getChain();
|
|
return true;
|
|
}
|
|
}
|
|
|
|
// Also handle the case where we explicitly require zeros in the top
|
|
// elements. This is a vector shuffle from the zero vector.
|
|
if (N.getOpcode() == ISD::VECTOR_SHUFFLE && N.Val->hasOneUse() &&
|
|
// Check to see if the top elements are all zeros (or bitcast of zeros).
|
|
ISD::isBuildVectorAllZeros(N.getOperand(0).Val) &&
|
|
N.getOperand(1).getOpcode() == ISD::SCALAR_TO_VECTOR &&
|
|
N.getOperand(1).Val->hasOneUse() &&
|
|
ISD::isNON_EXTLoad(N.getOperand(1).getOperand(0).Val) &&
|
|
N.getOperand(1).getOperand(0).hasOneUse()) {
|
|
// Check to see if the shuffle mask is 4/L/L/L or 2/L, where L is something
|
|
// from the LHS.
|
|
unsigned VecWidth=MVT::getVectorNumElements(N.getOperand(0).getValueType());
|
|
SDOperand ShufMask = N.getOperand(2);
|
|
assert(ShufMask.getOpcode() == ISD::BUILD_VECTOR && "Invalid shuf mask!");
|
|
if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(ShufMask.getOperand(0))) {
|
|
if (C->getValue() == VecWidth) {
|
|
for (unsigned i = 1; i != VecWidth; ++i) {
|
|
if (ShufMask.getOperand(i).getOpcode() == ISD::UNDEF) {
|
|
// ok.
|
|
} else {
|
|
ConstantSDNode *C = cast<ConstantSDNode>(ShufMask.getOperand(i));
|
|
if (C->getValue() >= VecWidth) return false;
|
|
}
|
|
}
|
|
}
|
|
|
|
// Okay, this is a zero extending load. Fold it.
|
|
LoadSDNode *LD = cast<LoadSDNode>(N.getOperand(1).getOperand(0));
|
|
if (!SelectAddr(Op, LD->getBasePtr(), Base, Scale, Index, Disp))
|
|
return false;
|
|
OutChain = LD->getChain();
|
|
InChain = SDOperand(LD, 1);
|
|
return true;
|
|
}
|
|
}
|
|
return false;
|
|
}
|
|
|
|
|
|
/// SelectLEAAddr - it calls SelectAddr and determines if the maximal addressing
|
|
/// mode it matches can be cost effectively emitted as an LEA instruction.
|
|
bool X86DAGToDAGISel::SelectLEAAddr(SDOperand Op, SDOperand N,
|
|
SDOperand &Base, SDOperand &Scale,
|
|
SDOperand &Index, SDOperand &Disp) {
|
|
X86ISelAddressMode AM;
|
|
if (MatchAddress(N, AM))
|
|
return false;
|
|
|
|
MVT::ValueType VT = N.getValueType();
|
|
unsigned Complexity = 0;
|
|
if (AM.BaseType == X86ISelAddressMode::RegBase)
|
|
if (AM.Base.Reg.Val)
|
|
Complexity = 1;
|
|
else
|
|
AM.Base.Reg = CurDAG->getRegister(0, VT);
|
|
else if (AM.BaseType == X86ISelAddressMode::FrameIndexBase)
|
|
Complexity = 4;
|
|
|
|
if (AM.IndexReg.Val)
|
|
Complexity++;
|
|
else
|
|
AM.IndexReg = CurDAG->getRegister(0, VT);
|
|
|
|
// Don't match just leal(,%reg,2). It's cheaper to do addl %reg, %reg, or with
|
|
// a simple shift.
|
|
if (AM.Scale > 1)
|
|
Complexity++;
|
|
|
|
// FIXME: We are artificially lowering the criteria to turn ADD %reg, $GA
|
|
// to a LEA. This is determined with some expermentation but is by no means
|
|
// optimal (especially for code size consideration). LEA is nice because of
|
|
// its three-address nature. Tweak the cost function again when we can run
|
|
// convertToThreeAddress() at register allocation time.
|
|
if (AM.GV || AM.CP || AM.ES || AM.JT != -1) {
|
|
// For X86-64, we should always use lea to materialize RIP relative
|
|
// addresses.
|
|
if (Subtarget->is64Bit())
|
|
Complexity = 4;
|
|
else
|
|
Complexity += 2;
|
|
}
|
|
|
|
if (AM.Disp && (AM.Base.Reg.Val || AM.IndexReg.Val))
|
|
Complexity++;
|
|
|
|
if (Complexity > 2) {
|
|
getAddressOperands(AM, Base, Scale, Index, Disp);
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
bool X86DAGToDAGISel::TryFoldLoad(SDOperand P, SDOperand N,
|
|
SDOperand &Base, SDOperand &Scale,
|
|
SDOperand &Index, SDOperand &Disp) {
|
|
if (ISD::isNON_EXTLoad(N.Val) &&
|
|
N.hasOneUse() &&
|
|
CanBeFoldedBy(N.Val, P.Val, P.Val))
|
|
return SelectAddr(P, N.getOperand(1), Base, Scale, Index, Disp);
|
|
return false;
|
|
}
|
|
|
|
/// getGlobalBaseReg - Output the instructions required to put the
|
|
/// base address to use for accessing globals into a register.
|
|
///
|
|
SDNode *X86DAGToDAGISel::getGlobalBaseReg() {
|
|
assert(!Subtarget->is64Bit() && "X86-64 PIC uses RIP relative addressing");
|
|
if (!GlobalBaseReg) {
|
|
// Insert the set of GlobalBaseReg into the first MBB of the function
|
|
MachineFunction *MF = BB->getParent();
|
|
MachineBasicBlock &FirstMBB = MF->front();
|
|
MachineBasicBlock::iterator MBBI = FirstMBB.begin();
|
|
MachineRegisterInfo &RegInfo = MF->getRegInfo();
|
|
unsigned PC = RegInfo.createVirtualRegister(X86::GR32RegisterClass);
|
|
|
|
const TargetInstrInfo *TII = TM.getInstrInfo();
|
|
// Operand of MovePCtoStack is completely ignored by asm printer. It's
|
|
// only used in JIT code emission as displacement to pc.
|
|
BuildMI(FirstMBB, MBBI, TII->get(X86::MOVPC32r), PC).addImm(0);
|
|
|
|
// If we're using vanilla 'GOT' PIC style, we should use relative addressing
|
|
// not to pc, but to _GLOBAL_ADDRESS_TABLE_ external
|
|
if (TM.getRelocationModel() == Reloc::PIC_ &&
|
|
Subtarget->isPICStyleGOT()) {
|
|
GlobalBaseReg = RegInfo.createVirtualRegister(X86::GR32RegisterClass);
|
|
BuildMI(FirstMBB, MBBI, TII->get(X86::ADD32ri), GlobalBaseReg)
|
|
.addReg(PC).addExternalSymbol("_GLOBAL_OFFSET_TABLE_");
|
|
} else {
|
|
GlobalBaseReg = PC;
|
|
}
|
|
|
|
}
|
|
return CurDAG->getRegister(GlobalBaseReg, TLI.getPointerTy()).Val;
|
|
}
|
|
|
|
static SDNode *FindCallStartFromCall(SDNode *Node) {
|
|
if (Node->getOpcode() == ISD::CALLSEQ_START) return Node;
|
|
assert(Node->getOperand(0).getValueType() == MVT::Other &&
|
|
"Node doesn't have a token chain argument!");
|
|
return FindCallStartFromCall(Node->getOperand(0).Val);
|
|
}
|
|
|
|
SDNode *X86DAGToDAGISel::getTruncate(SDOperand N0, MVT::ValueType VT) {
|
|
SDOperand SRIdx;
|
|
switch (VT) {
|
|
case MVT::i8:
|
|
SRIdx = CurDAG->getTargetConstant(1, MVT::i32); // SubRegSet 1
|
|
// Ensure that the source register has an 8-bit subreg on 32-bit targets
|
|
if (!Subtarget->is64Bit()) {
|
|
unsigned Opc;
|
|
MVT::ValueType VT;
|
|
switch (N0.getValueType()) {
|
|
default: assert(0 && "Unknown truncate!");
|
|
case MVT::i16:
|
|
Opc = X86::MOV16to16_;
|
|
VT = MVT::i16;
|
|
break;
|
|
case MVT::i32:
|
|
Opc = X86::MOV32to32_;
|
|
VT = MVT::i32;
|
|
break;
|
|
}
|
|
N0 = SDOperand(CurDAG->getTargetNode(Opc, VT, MVT::Flag, N0), 0);
|
|
return CurDAG->getTargetNode(X86::EXTRACT_SUBREG,
|
|
VT, N0, SRIdx, N0.getValue(1));
|
|
}
|
|
break;
|
|
case MVT::i16:
|
|
SRIdx = CurDAG->getTargetConstant(2, MVT::i32); // SubRegSet 2
|
|
break;
|
|
case MVT::i32:
|
|
SRIdx = CurDAG->getTargetConstant(3, MVT::i32); // SubRegSet 3
|
|
break;
|
|
default: assert(0 && "Unknown truncate!"); break;
|
|
}
|
|
return CurDAG->getTargetNode(X86::EXTRACT_SUBREG, VT, N0, SRIdx);
|
|
}
|
|
|
|
|
|
SDNode *X86DAGToDAGISel::Select(SDOperand N) {
|
|
SDNode *Node = N.Val;
|
|
MVT::ValueType NVT = Node->getValueType(0);
|
|
unsigned Opc, MOpc;
|
|
unsigned Opcode = Node->getOpcode();
|
|
|
|
#ifndef NDEBUG
|
|
DOUT << std::string(Indent, ' ') << "Selecting: ";
|
|
DEBUG(Node->dump(CurDAG));
|
|
DOUT << "\n";
|
|
Indent += 2;
|
|
#endif
|
|
|
|
if (Opcode >= ISD::BUILTIN_OP_END && Opcode < X86ISD::FIRST_NUMBER) {
|
|
#ifndef NDEBUG
|
|
DOUT << std::string(Indent-2, ' ') << "== ";
|
|
DEBUG(Node->dump(CurDAG));
|
|
DOUT << "\n";
|
|
Indent -= 2;
|
|
#endif
|
|
return NULL; // Already selected.
|
|
}
|
|
|
|
switch (Opcode) {
|
|
default: break;
|
|
case X86ISD::GlobalBaseReg:
|
|
return getGlobalBaseReg();
|
|
|
|
case ISD::ADD: {
|
|
// Turn ADD X, c to MOV32ri X+c. This cannot be done with tblgen'd
|
|
// code and is matched first so to prevent it from being turned into
|
|
// LEA32r X+c.
|
|
// In 64-bit mode, use LEA to take advantage of RIP-relative addressing.
|
|
MVT::ValueType PtrVT = TLI.getPointerTy();
|
|
SDOperand N0 = N.getOperand(0);
|
|
SDOperand N1 = N.getOperand(1);
|
|
if (N.Val->getValueType(0) == PtrVT &&
|
|
N0.getOpcode() == X86ISD::Wrapper &&
|
|
N1.getOpcode() == ISD::Constant) {
|
|
unsigned Offset = (unsigned)cast<ConstantSDNode>(N1)->getValue();
|
|
SDOperand C(0, 0);
|
|
// TODO: handle ExternalSymbolSDNode.
|
|
if (GlobalAddressSDNode *G =
|
|
dyn_cast<GlobalAddressSDNode>(N0.getOperand(0))) {
|
|
C = CurDAG->getTargetGlobalAddress(G->getGlobal(), PtrVT,
|
|
G->getOffset() + Offset);
|
|
} else if (ConstantPoolSDNode *CP =
|
|
dyn_cast<ConstantPoolSDNode>(N0.getOperand(0))) {
|
|
C = CurDAG->getTargetConstantPool(CP->getConstVal(), PtrVT,
|
|
CP->getAlignment(),
|
|
CP->getOffset()+Offset);
|
|
}
|
|
|
|
if (C.Val) {
|
|
if (Subtarget->is64Bit()) {
|
|
SDOperand Ops[] = { CurDAG->getRegister(0, PtrVT), getI8Imm(1),
|
|
CurDAG->getRegister(0, PtrVT), C };
|
|
return CurDAG->SelectNodeTo(N.Val, X86::LEA64r, MVT::i64, Ops, 4);
|
|
} else
|
|
return CurDAG->SelectNodeTo(N.Val, X86::MOV32ri, PtrVT, C);
|
|
}
|
|
}
|
|
|
|
// Other cases are handled by auto-generated code.
|
|
break;
|
|
}
|
|
|
|
case ISD::SMUL_LOHI:
|
|
case ISD::UMUL_LOHI: {
|
|
SDOperand N0 = Node->getOperand(0);
|
|
SDOperand N1 = Node->getOperand(1);
|
|
|
|
// There are several forms of IMUL that just return the low part and
|
|
// don't have fixed-register operands. If we don't need the high part,
|
|
// use these instead. They can be selected with the generated ISel code.
|
|
if (NVT != MVT::i8 &&
|
|
N.getValue(1).use_empty()) {
|
|
N = CurDAG->getNode(ISD::MUL, NVT, N0, N1);
|
|
break;
|
|
}
|
|
|
|
bool isSigned = Opcode == ISD::SMUL_LOHI;
|
|
if (!isSigned)
|
|
switch (NVT) {
|
|
default: assert(0 && "Unsupported VT!");
|
|
case MVT::i8: Opc = X86::MUL8r; MOpc = X86::MUL8m; break;
|
|
case MVT::i16: Opc = X86::MUL16r; MOpc = X86::MUL16m; break;
|
|
case MVT::i32: Opc = X86::MUL32r; MOpc = X86::MUL32m; break;
|
|
case MVT::i64: Opc = X86::MUL64r; MOpc = X86::MUL64m; break;
|
|
}
|
|
else
|
|
switch (NVT) {
|
|
default: assert(0 && "Unsupported VT!");
|
|
case MVT::i8: Opc = X86::IMUL8r; MOpc = X86::IMUL8m; break;
|
|
case MVT::i16: Opc = X86::IMUL16r; MOpc = X86::IMUL16m; break;
|
|
case MVT::i32: Opc = X86::IMUL32r; MOpc = X86::IMUL32m; break;
|
|
case MVT::i64: Opc = X86::IMUL64r; MOpc = X86::IMUL64m; break;
|
|
}
|
|
|
|
unsigned LoReg, HiReg;
|
|
switch (NVT) {
|
|
default: assert(0 && "Unsupported VT!");
|
|
case MVT::i8: LoReg = X86::AL; HiReg = X86::AH; break;
|
|
case MVT::i16: LoReg = X86::AX; HiReg = X86::DX; break;
|
|
case MVT::i32: LoReg = X86::EAX; HiReg = X86::EDX; break;
|
|
case MVT::i64: LoReg = X86::RAX; HiReg = X86::RDX; break;
|
|
}
|
|
|
|
SDOperand Tmp0, Tmp1, Tmp2, Tmp3;
|
|
bool foldedLoad = TryFoldLoad(N, N1, Tmp0, Tmp1, Tmp2, Tmp3);
|
|
// multiplty is commmutative
|
|
if (!foldedLoad) {
|
|
foldedLoad = TryFoldLoad(N, N0, Tmp0, Tmp1, Tmp2, Tmp3);
|
|
if (foldedLoad)
|
|
std::swap(N0, N1);
|
|
}
|
|
|
|
AddToISelQueue(N0);
|
|
SDOperand InFlag = CurDAG->getCopyToReg(CurDAG->getEntryNode(), LoReg,
|
|
N0, SDOperand()).getValue(1);
|
|
|
|
if (foldedLoad) {
|
|
AddToISelQueue(N1.getOperand(0));
|
|
AddToISelQueue(Tmp0);
|
|
AddToISelQueue(Tmp1);
|
|
AddToISelQueue(Tmp2);
|
|
AddToISelQueue(Tmp3);
|
|
SDOperand Ops[] = { Tmp0, Tmp1, Tmp2, Tmp3, N1.getOperand(0), InFlag };
|
|
SDNode *CNode =
|
|
CurDAG->getTargetNode(MOpc, MVT::Other, MVT::Flag, Ops, 6);
|
|
InFlag = SDOperand(CNode, 1);
|
|
// Update the chain.
|
|
ReplaceUses(N1.getValue(1), SDOperand(CNode, 0));
|
|
} else {
|
|
AddToISelQueue(N1);
|
|
InFlag =
|
|
SDOperand(CurDAG->getTargetNode(Opc, MVT::Flag, N1, InFlag), 0);
|
|
}
|
|
|
|
// Copy the low half of the result, if it is needed.
|
|
if (!N.getValue(0).use_empty()) {
|
|
SDOperand Result = CurDAG->getCopyFromReg(CurDAG->getEntryNode(),
|
|
LoReg, NVT, InFlag);
|
|
InFlag = Result.getValue(2);
|
|
ReplaceUses(N.getValue(0), Result);
|
|
#ifndef NDEBUG
|
|
DOUT << std::string(Indent-2, ' ') << "=> ";
|
|
DEBUG(Result.Val->dump(CurDAG));
|
|
DOUT << "\n";
|
|
#endif
|
|
}
|
|
// Copy the high half of the result, if it is needed.
|
|
if (!N.getValue(1).use_empty()) {
|
|
SDOperand Result;
|
|
if (HiReg == X86::AH && Subtarget->is64Bit()) {
|
|
// Prevent use of AH in a REX instruction by referencing AX instead.
|
|
// Shift it down 8 bits.
|
|
Result = CurDAG->getCopyFromReg(CurDAG->getEntryNode(),
|
|
X86::AX, MVT::i16, InFlag);
|
|
InFlag = Result.getValue(2);
|
|
Result = SDOperand(CurDAG->getTargetNode(X86::SHR16ri, MVT::i16, Result,
|
|
CurDAG->getTargetConstant(8, MVT::i8)), 0);
|
|
// Then truncate it down to i8.
|
|
SDOperand SRIdx = CurDAG->getTargetConstant(1, MVT::i32); // SubRegSet 1
|
|
Result = SDOperand(CurDAG->getTargetNode(X86::EXTRACT_SUBREG,
|
|
MVT::i8, Result, SRIdx), 0);
|
|
} else {
|
|
Result = CurDAG->getCopyFromReg(CurDAG->getEntryNode(),
|
|
HiReg, NVT, InFlag);
|
|
InFlag = Result.getValue(2);
|
|
}
|
|
ReplaceUses(N.getValue(1), Result);
|
|
#ifndef NDEBUG
|
|
DOUT << std::string(Indent-2, ' ') << "=> ";
|
|
DEBUG(Result.Val->dump(CurDAG));
|
|
DOUT << "\n";
|
|
#endif
|
|
}
|
|
|
|
#ifndef NDEBUG
|
|
Indent -= 2;
|
|
#endif
|
|
|
|
return NULL;
|
|
}
|
|
|
|
case ISD::SDIVREM:
|
|
case ISD::UDIVREM: {
|
|
SDOperand N0 = Node->getOperand(0);
|
|
SDOperand N1 = Node->getOperand(1);
|
|
|
|
bool isSigned = Opcode == ISD::SDIVREM;
|
|
if (!isSigned)
|
|
switch (NVT) {
|
|
default: assert(0 && "Unsupported VT!");
|
|
case MVT::i8: Opc = X86::DIV8r; MOpc = X86::DIV8m; break;
|
|
case MVT::i16: Opc = X86::DIV16r; MOpc = X86::DIV16m; break;
|
|
case MVT::i32: Opc = X86::DIV32r; MOpc = X86::DIV32m; break;
|
|
case MVT::i64: Opc = X86::DIV64r; MOpc = X86::DIV64m; break;
|
|
}
|
|
else
|
|
switch (NVT) {
|
|
default: assert(0 && "Unsupported VT!");
|
|
case MVT::i8: Opc = X86::IDIV8r; MOpc = X86::IDIV8m; break;
|
|
case MVT::i16: Opc = X86::IDIV16r; MOpc = X86::IDIV16m; break;
|
|
case MVT::i32: Opc = X86::IDIV32r; MOpc = X86::IDIV32m; break;
|
|
case MVT::i64: Opc = X86::IDIV64r; MOpc = X86::IDIV64m; break;
|
|
}
|
|
|
|
unsigned LoReg, HiReg;
|
|
unsigned ClrOpcode, SExtOpcode;
|
|
switch (NVT) {
|
|
default: assert(0 && "Unsupported VT!");
|
|
case MVT::i8:
|
|
LoReg = X86::AL; HiReg = X86::AH;
|
|
ClrOpcode = 0;
|
|
SExtOpcode = X86::CBW;
|
|
break;
|
|
case MVT::i16:
|
|
LoReg = X86::AX; HiReg = X86::DX;
|
|
ClrOpcode = X86::MOV16r0;
|
|
SExtOpcode = X86::CWD;
|
|
break;
|
|
case MVT::i32:
|
|
LoReg = X86::EAX; HiReg = X86::EDX;
|
|
ClrOpcode = X86::MOV32r0;
|
|
SExtOpcode = X86::CDQ;
|
|
break;
|
|
case MVT::i64:
|
|
LoReg = X86::RAX; HiReg = X86::RDX;
|
|
ClrOpcode = X86::MOV64r0;
|
|
SExtOpcode = X86::CQO;
|
|
break;
|
|
}
|
|
|
|
SDOperand Tmp0, Tmp1, Tmp2, Tmp3;
|
|
bool foldedLoad = TryFoldLoad(N, N1, Tmp0, Tmp1, Tmp2, Tmp3);
|
|
|
|
SDOperand InFlag;
|
|
if (NVT == MVT::i8 && !isSigned) {
|
|
// Special case for div8, just use a move with zero extension to AX to
|
|
// clear the upper 8 bits (AH).
|
|
SDOperand Tmp0, Tmp1, Tmp2, Tmp3, Move, Chain;
|
|
if (TryFoldLoad(N, N0, Tmp0, Tmp1, Tmp2, Tmp3)) {
|
|
SDOperand Ops[] = { Tmp0, Tmp1, Tmp2, Tmp3, N0.getOperand(0) };
|
|
AddToISelQueue(N0.getOperand(0));
|
|
AddToISelQueue(Tmp0);
|
|
AddToISelQueue(Tmp1);
|
|
AddToISelQueue(Tmp2);
|
|
AddToISelQueue(Tmp3);
|
|
Move =
|
|
SDOperand(CurDAG->getTargetNode(X86::MOVZX16rm8, MVT::i16, MVT::Other,
|
|
Ops, 5), 0);
|
|
Chain = Move.getValue(1);
|
|
ReplaceUses(N0.getValue(1), Chain);
|
|
} else {
|
|
AddToISelQueue(N0);
|
|
Move =
|
|
SDOperand(CurDAG->getTargetNode(X86::MOVZX16rr8, MVT::i16, N0), 0);
|
|
Chain = CurDAG->getEntryNode();
|
|
}
|
|
Chain = CurDAG->getCopyToReg(Chain, X86::AX, Move, SDOperand());
|
|
InFlag = Chain.getValue(1);
|
|
} else {
|
|
AddToISelQueue(N0);
|
|
InFlag =
|
|
CurDAG->getCopyToReg(CurDAG->getEntryNode(),
|
|
LoReg, N0, SDOperand()).getValue(1);
|
|
if (isSigned) {
|
|
// Sign extend the low part into the high part.
|
|
InFlag =
|
|
SDOperand(CurDAG->getTargetNode(SExtOpcode, MVT::Flag, InFlag), 0);
|
|
} else {
|
|
// Zero out the high part, effectively zero extending the input.
|
|
SDOperand ClrNode = SDOperand(CurDAG->getTargetNode(ClrOpcode, NVT), 0);
|
|
InFlag = CurDAG->getCopyToReg(CurDAG->getEntryNode(), HiReg,
|
|
ClrNode, InFlag).getValue(1);
|
|
}
|
|
}
|
|
|
|
if (foldedLoad) {
|
|
AddToISelQueue(N1.getOperand(0));
|
|
AddToISelQueue(Tmp0);
|
|
AddToISelQueue(Tmp1);
|
|
AddToISelQueue(Tmp2);
|
|
AddToISelQueue(Tmp3);
|
|
SDOperand Ops[] = { Tmp0, Tmp1, Tmp2, Tmp3, N1.getOperand(0), InFlag };
|
|
SDNode *CNode =
|
|
CurDAG->getTargetNode(MOpc, MVT::Other, MVT::Flag, Ops, 6);
|
|
InFlag = SDOperand(CNode, 1);
|
|
// Update the chain.
|
|
ReplaceUses(N1.getValue(1), SDOperand(CNode, 0));
|
|
} else {
|
|
AddToISelQueue(N1);
|
|
InFlag =
|
|
SDOperand(CurDAG->getTargetNode(Opc, MVT::Flag, N1, InFlag), 0);
|
|
}
|
|
|
|
// Copy the division (low) result, if it is needed.
|
|
if (!N.getValue(0).use_empty()) {
|
|
SDOperand Result = CurDAG->getCopyFromReg(CurDAG->getEntryNode(),
|
|
LoReg, NVT, InFlag);
|
|
InFlag = Result.getValue(2);
|
|
ReplaceUses(N.getValue(0), Result);
|
|
#ifndef NDEBUG
|
|
DOUT << std::string(Indent-2, ' ') << "=> ";
|
|
DEBUG(Result.Val->dump(CurDAG));
|
|
DOUT << "\n";
|
|
#endif
|
|
}
|
|
// Copy the remainder (high) result, if it is needed.
|
|
if (!N.getValue(1).use_empty()) {
|
|
SDOperand Result;
|
|
if (HiReg == X86::AH && Subtarget->is64Bit()) {
|
|
// Prevent use of AH in a REX instruction by referencing AX instead.
|
|
// Shift it down 8 bits.
|
|
Result = CurDAG->getCopyFromReg(CurDAG->getEntryNode(),
|
|
X86::AX, MVT::i16, InFlag);
|
|
InFlag = Result.getValue(2);
|
|
Result = SDOperand(CurDAG->getTargetNode(X86::SHR16ri, MVT::i16, Result,
|
|
CurDAG->getTargetConstant(8, MVT::i8)), 0);
|
|
// Then truncate it down to i8.
|
|
SDOperand SRIdx = CurDAG->getTargetConstant(1, MVT::i32); // SubRegSet 1
|
|
Result = SDOperand(CurDAG->getTargetNode(X86::EXTRACT_SUBREG,
|
|
MVT::i8, Result, SRIdx), 0);
|
|
} else {
|
|
Result = CurDAG->getCopyFromReg(CurDAG->getEntryNode(),
|
|
HiReg, NVT, InFlag);
|
|
InFlag = Result.getValue(2);
|
|
}
|
|
ReplaceUses(N.getValue(1), Result);
|
|
#ifndef NDEBUG
|
|
DOUT << std::string(Indent-2, ' ') << "=> ";
|
|
DEBUG(Result.Val->dump(CurDAG));
|
|
DOUT << "\n";
|
|
#endif
|
|
}
|
|
|
|
#ifndef NDEBUG
|
|
Indent -= 2;
|
|
#endif
|
|
|
|
return NULL;
|
|
}
|
|
|
|
case ISD::ANY_EXTEND: {
|
|
SDOperand N0 = Node->getOperand(0);
|
|
AddToISelQueue(N0);
|
|
if (NVT == MVT::i64 || NVT == MVT::i32 || NVT == MVT::i16) {
|
|
SDOperand SRIdx;
|
|
switch(N0.getValueType()) {
|
|
case MVT::i32:
|
|
SRIdx = CurDAG->getTargetConstant(3, MVT::i32); // SubRegSet 3
|
|
break;
|
|
case MVT::i16:
|
|
SRIdx = CurDAG->getTargetConstant(2, MVT::i32); // SubRegSet 2
|
|
break;
|
|
case MVT::i8:
|
|
if (Subtarget->is64Bit())
|
|
SRIdx = CurDAG->getTargetConstant(1, MVT::i32); // SubRegSet 1
|
|
break;
|
|
default: assert(0 && "Unknown any_extend!");
|
|
}
|
|
if (SRIdx.Val) {
|
|
SDNode *ResNode = CurDAG->getTargetNode(X86::INSERT_SUBREG,
|
|
NVT, N0, SRIdx);
|
|
|
|
#ifndef NDEBUG
|
|
DOUT << std::string(Indent-2, ' ') << "=> ";
|
|
DEBUG(ResNode->dump(CurDAG));
|
|
DOUT << "\n";
|
|
Indent -= 2;
|
|
#endif
|
|
return ResNode;
|
|
} // Otherwise let generated ISel handle it.
|
|
}
|
|
break;
|
|
}
|
|
|
|
case ISD::SIGN_EXTEND_INREG: {
|
|
SDOperand N0 = Node->getOperand(0);
|
|
AddToISelQueue(N0);
|
|
|
|
MVT::ValueType SVT = cast<VTSDNode>(Node->getOperand(1))->getVT();
|
|
SDOperand TruncOp = SDOperand(getTruncate(N0, SVT), 0);
|
|
unsigned Opc = 0;
|
|
switch (NVT) {
|
|
case MVT::i16:
|
|
if (SVT == MVT::i8) Opc = X86::MOVSX16rr8;
|
|
else assert(0 && "Unknown sign_extend_inreg!");
|
|
break;
|
|
case MVT::i32:
|
|
switch (SVT) {
|
|
case MVT::i8: Opc = X86::MOVSX32rr8; break;
|
|
case MVT::i16: Opc = X86::MOVSX32rr16; break;
|
|
default: assert(0 && "Unknown sign_extend_inreg!");
|
|
}
|
|
break;
|
|
case MVT::i64:
|
|
switch (SVT) {
|
|
case MVT::i8: Opc = X86::MOVSX64rr8; break;
|
|
case MVT::i16: Opc = X86::MOVSX64rr16; break;
|
|
case MVT::i32: Opc = X86::MOVSX64rr32; break;
|
|
default: assert(0 && "Unknown sign_extend_inreg!");
|
|
}
|
|
break;
|
|
default: assert(0 && "Unknown sign_extend_inreg!");
|
|
}
|
|
|
|
SDNode *ResNode = CurDAG->getTargetNode(Opc, NVT, TruncOp);
|
|
|
|
#ifndef NDEBUG
|
|
DOUT << std::string(Indent-2, ' ') << "=> ";
|
|
DEBUG(TruncOp.Val->dump(CurDAG));
|
|
DOUT << "\n";
|
|
DOUT << std::string(Indent-2, ' ') << "=> ";
|
|
DEBUG(ResNode->dump(CurDAG));
|
|
DOUT << "\n";
|
|
Indent -= 2;
|
|
#endif
|
|
return ResNode;
|
|
break;
|
|
}
|
|
|
|
case ISD::TRUNCATE: {
|
|
SDOperand Input = Node->getOperand(0);
|
|
AddToISelQueue(Node->getOperand(0));
|
|
SDNode *ResNode = getTruncate(Input, NVT);
|
|
|
|
#ifndef NDEBUG
|
|
DOUT << std::string(Indent-2, ' ') << "=> ";
|
|
DEBUG(ResNode->dump(CurDAG));
|
|
DOUT << "\n";
|
|
Indent -= 2;
|
|
#endif
|
|
return ResNode;
|
|
break;
|
|
}
|
|
}
|
|
|
|
SDNode *ResNode = SelectCode(N);
|
|
|
|
#ifndef NDEBUG
|
|
DOUT << std::string(Indent-2, ' ') << "=> ";
|
|
if (ResNode == NULL || ResNode == N.Val)
|
|
DEBUG(N.Val->dump(CurDAG));
|
|
else
|
|
DEBUG(ResNode->dump(CurDAG));
|
|
DOUT << "\n";
|
|
Indent -= 2;
|
|
#endif
|
|
|
|
return ResNode;
|
|
}
|
|
|
|
bool X86DAGToDAGISel::
|
|
SelectInlineAsmMemoryOperand(const SDOperand &Op, char ConstraintCode,
|
|
std::vector<SDOperand> &OutOps, SelectionDAG &DAG){
|
|
SDOperand Op0, Op1, Op2, Op3;
|
|
switch (ConstraintCode) {
|
|
case 'o': // offsetable ??
|
|
case 'v': // not offsetable ??
|
|
default: return true;
|
|
case 'm': // memory
|
|
if (!SelectAddr(Op, Op, Op0, Op1, Op2, Op3))
|
|
return true;
|
|
break;
|
|
}
|
|
|
|
OutOps.push_back(Op0);
|
|
OutOps.push_back(Op1);
|
|
OutOps.push_back(Op2);
|
|
OutOps.push_back(Op3);
|
|
AddToISelQueue(Op0);
|
|
AddToISelQueue(Op1);
|
|
AddToISelQueue(Op2);
|
|
AddToISelQueue(Op3);
|
|
return false;
|
|
}
|
|
|
|
/// createX86ISelDag - This pass converts a legalized DAG into a
|
|
/// X86-specific DAG, ready for instruction scheduling.
|
|
///
|
|
FunctionPass *llvm::createX86ISelDag(X86TargetMachine &TM, bool Fast) {
|
|
return new X86DAGToDAGISel(TM, Fast);
|
|
}
|