Add Om1 lowering with no optimizations

src/IceTargetLoweringX8632.h

+//===- subzero/src/IceTargetLoweringX8632.h - x86-32 lowering ---*- C++ -*-===//
+//
+//                        The Subzero Code Generator
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file declares the TargetLoweringX8632 class, which
+// implements the TargetLowering interface for the x86-32
+// architecture.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef SUBZERO_SRC_ICETARGETLOWERINGX8632_H
+#define SUBZERO_SRC_ICETARGETLOWERINGX8632_H
+
+#include "IceDefs.h"
+#include "IceTargetLowering.h"
+#include "IceInstX8632.h"
+
+namespace Ice {
+
+class TargetX8632 : public TargetLowering {
+public:
+  static TargetX8632 *create(Cfg *Func) { return new TargetX8632(Func); }
+
+  virtual void translateOm1();
+
+  virtual Variable *getPhysicalRegister(SizeT RegNum);
+  virtual IceString getRegName(SizeT RegNum, Type Ty) const;
+  virtual llvm::SmallBitVector getRegisterSet(RegSetMask Include,
+                                              RegSetMask Exclude) const;
+  virtual const llvm::SmallBitVector &getRegisterSetForType(Type Ty) const {
+    return TypeToRegisterSet[Ty];
+  }
+  virtual bool hasFramePointer() const { return IsEbpBasedFrame; }
+  virtual SizeT getFrameOrStackReg() const {
+    return IsEbpBasedFrame ? Reg_ebp : Reg_esp;
+  }
+  virtual size_t typeWidthInBytesOnStack(Type Ty) {
+    // Round up to the next multiple of 4 bytes.  In particular, i1,
+    // i8, and i16 are rounded up to 4 bytes.
+    return (typeWidthInBytes(Ty) + 3) & ~3;
+  }
+  virtual void emitVariable(const Variable *Var, const Cfg *Func) const;
+  virtual void addProlog(CfgNode *Node);
+  virtual void addEpilog(CfgNode *Node);
+  SizeT makeNextLabelNumber() { return NextLabelNumber++; }
+  // Ensure that a 64-bit Variable has been split into 2 32-bit
+  // Variables, creating them if necessary.  This is needed for all
+  // I64 operations, and it is needed for pushing F64 arguments for
+  // function calls using the 32-bit push instruction (though the
+  // latter could be done by directly writing to the stack).
+  void split64(Variable *Var);
+  void setArgOffsetAndCopy(Variable *Arg, Variable *FramePtr,
+                           int32_t BasicFrameOffset, int32_t &InArgsSizeBytes);
+  Operand *loOperand(Operand *Operand);
+  Operand *hiOperand(Operand *Operand);
+
+  enum Registers {
+#define X(val, init, name, name16, name8, scratch, preserved, stackptr,        \
+          frameptr, isI8, isInt, isFP)                                         \
+  val init,
+    REGX8632_TABLE
+#undef X
+        Reg_NUM
+  };
+
+protected:
+  TargetX8632(Cfg *Func);
+
+  virtual void postLower();
+
+  virtual void lowerAlloca(const InstAlloca *Inst);
+  virtual void lowerArithmetic(const InstArithmetic *Inst);
+  virtual void lowerAssign(const InstAssign *Inst);
+  virtual void lowerBr(const InstBr *Inst);
+  virtual void lowerCall(const InstCall *Inst);
+  virtual void lowerCast(const InstCast *Inst);
+  virtual void lowerFcmp(const InstFcmp *Inst);
+  virtual void lowerIcmp(const InstIcmp *Inst);
+  virtual void lowerLoad(const InstLoad *Inst);
+  virtual void lowerPhi(const InstPhi *Inst);
+  virtual void lowerRet(const InstRet *Inst);
+  virtual void lowerSelect(const InstSelect *Inst);
+  virtual void lowerStore(const InstStore *Inst);
+  virtual void lowerSwitch(const InstSwitch *Inst);
+  virtual void lowerUnreachable(const InstUnreachable *Inst);
+
+  enum OperandLegalization {
+    Legal_None = 0,
+    Legal_Reg = 1 << 0,
+    Legal_Imm = 1 << 1,
+    Legal_Mem = 1 << 2, // includes [eax+4*ecx] as well as [esp+12]
+    Legal_All = ~Legal_None
+  };
+  typedef uint32_t LegalMask;
+  Operand *legalize(Operand *From, LegalMask Allowed = Legal_All,

[jvoung (off chromium), 2014/05/15 23:47:34]

Does it make sense to leave a comment for the legalize() method and the related
enum?

I take it this is to avoid having instructions w/out at least one register
operand. Well, there's more to it than that so ... if you think of a short
comment, otherwise might as well look at the code =)

[Jim Stichnoth, 2014/05/17 14:14:32]

Yeah, that's a good idea.  I left a comment here, and some more in the source
code.

+                    bool AllowOverlap = false,
+                    int32_t RegNum = Variable::NoRegister);
+  Variable *legalizeToVar(Operand *From, bool AllowOverlap = false,
+                          int32_t RegNum = Variable::NoRegister);
+  Variable *makeReg(Type Ty, int32_t RegNum = Variable::NoRegister);
+  InstCall *makeHelperCall(const IceString &Name, Variable *Dest,
+                           SizeT MaxSrcs) {
+    bool SuppressMangling = true;
+    Type Ty = Dest ? Dest->getType() : IceType_void;
+    Constant *CallTarget = Ctx->getConstantSym(Ty, 0, Name, SuppressMangling);
+    InstCall *Call = InstCall::create(Func, MaxSrcs, Dest, CallTarget);
+    return Call;
+  }
+
+  // The following are helpers that insert lowered x86 instructions
+  // with minimal syntactic overhead, so that the lowering code can
+  // look as close to assembly as practical.
+  void _adc(Variable *Dest, Operand *Src0) {
+    Context.insert(InstX8632Adc::create(Func, Dest, Src0));
+  }
+  void _add(Variable *Dest, Operand *Src0) {
+    Context.insert(InstX8632Add::create(Func, Dest, Src0));
+  }
+  void _addss(Variable *Dest, Operand *Src0) {
+    Context.insert(InstX8632Addss::create(Func, Dest, Src0));
+  }
+  void _and(Variable *Dest, Operand *Src0) {
+    Context.insert(InstX8632And::create(Func, Dest, Src0));
+  }
+  void _br(InstX8632Br::BrCond Condition, CfgNode *TargetTrue,
+           CfgNode *TargetFalse) {
+    Context.insert(
+        InstX8632Br::create(Func, TargetTrue, TargetFalse, Condition));
+  }
+  void _br(CfgNode *Target) {
+    Context.insert(InstX8632Br::create(Func, Target));
+  }
+  void _br(InstX8632Br::BrCond Condition, CfgNode *Target) {
+    Context.insert(InstX8632Br::create(Func, Target, Condition));
+  }
+  void _br(InstX8632Br::BrCond Condition, InstX8632Label *Label) {
+    Context.insert(InstX8632Br::create(Func, Label, Condition));
+  }
+  void _cdq(Variable *Dest, Operand *Src0) {
+    Context.insert(InstX8632Cdq::create(Func, Dest, Src0));
+  }
+  void _cmp(Operand *Src0, Operand *Src1) {
+    Context.insert(InstX8632Icmp::create(Func, Src0, Src1));
+  }
+  void _cvt(Variable *Dest, Operand *Src0) {
+    Context.insert(InstX8632Cvt::create(Func, Dest, Src0));
+  }
+  void _div(Variable *Dest, Operand *Src0, Operand *Src1) {
+    Context.insert(InstX8632Div::create(Func, Dest, Src0, Src1));
+  }
+  void _divss(Variable *Dest, Operand *Src0) {
+    Context.insert(InstX8632Divss::create(Func, Dest, Src0));
+  }
+  void _fld(Operand *Src0) { Context.insert(InstX8632Fld::create(Func, Src0)); }
+  void _fstp(Variable *Dest) {
+    Context.insert(InstX8632Fstp::create(Func, Dest));
+  }
+  void _idiv(Variable *Dest, Operand *Src0, Operand *Src1) {
+    Context.insert(InstX8632Idiv::create(Func, Dest, Src0, Src1));
+  }
+  void _imul(Variable *Dest, Operand *Src0) {
+    Context.insert(InstX8632Imul::create(Func, Dest, Src0));
+  }
+  // If Dest=NULL is passed in, then a new variable is created, marked
+  // as infinite register allocation weight, and returned through the
+  // in/out Dest argument.
+  void _mov(Variable *&Dest, Operand *Src0,
+            int32_t RegNum = Variable::NoRegister) {
+    if (Dest == NULL) {
+      Dest = legalizeToVar(Src0, false, RegNum);
+    } else {
+      Context.insert(InstX8632Mov::create(Func, Dest, Src0));
+    }
+  }
+  void _movsx(Variable *Dest, Operand *Src0) {
+    Context.insert(InstX8632Movsx::create(Func, Dest, Src0));
+  }
+  void _movzx(Variable *Dest, Operand *Src0) {
+    Context.insert(InstX8632Movzx::create(Func, Dest, Src0));
+  }
+  void _mul(Variable *Dest, Variable *Src0, Operand *Src1) {
+    Context.insert(InstX8632Mul::create(Func, Dest, Src0, Src1));
+  }
+  void _mulss(Variable *Dest, Operand *Src0) {
+    Context.insert(InstX8632Mulss::create(Func, Dest, Src0));
+  }
+  void _or(Variable *Dest, Operand *Src0) {
+    Context.insert(InstX8632Or::create(Func, Dest, Src0));
+  }
+  void _pop(Variable *Dest) {
+    Context.insert(InstX8632Pop::create(Func, Dest));
+  }
+  void _push(Operand *Src0, bool SuppressStackAdjustment = false) {
+    Context.insert(InstX8632Push::create(Func, Src0, SuppressStackAdjustment));
+  }
+  void _ret(Variable *Src0 = NULL) {
+    Context.insert(InstX8632Ret::create(Func, Src0));
+  }
+  void _sar(Variable *Dest, Operand *Src0) {
+    Context.insert(InstX8632Sar::create(Func, Dest, Src0));
+  }
+  void _sbb(Variable *Dest, Operand *Src0) {
+    Context.insert(InstX8632Sbb::create(Func, Dest, Src0));
+  }
+  void _shl(Variable *Dest, Operand *Src0) {
+    Context.insert(InstX8632Shl::create(Func, Dest, Src0));
+  }
+  void _shld(Variable *Dest, Variable *Src0, Variable *Src1) {
+    Context.insert(InstX8632Shld::create(Func, Dest, Src0, Src1));
+  }
+  void _shr(Variable *Dest, Operand *Src0) {
+    Context.insert(InstX8632Shr::create(Func, Dest, Src0));
+  }
+  void _shrd(Variable *Dest, Variable *Src0, Variable *Src1) {
+    Context.insert(InstX8632Shrd::create(Func, Dest, Src0, Src1));
+  }
+  void _store(Operand *Value, OperandX8632 *Mem) {
+    Context.insert(InstX8632Store::create(Func, Value, Mem));
+  }
+  void _sub(Variable *Dest, Operand *Src0) {
+    Context.insert(InstX8632Sub::create(Func, Dest, Src0));
+  }
+  void _subss(Variable *Dest, Operand *Src0) {
+    Context.insert(InstX8632Subss::create(Func, Dest, Src0));
+  }
+  void _test(Operand *Src0, Operand *Src1) {
+    Context.insert(InstX8632Test::create(Func, Src0, Src1));
+  }
+  void _ucomiss(Operand *Src0, Operand *Src1) {
+    Context.insert(InstX8632Ucomiss::create(Func, Src0, Src1));
+  }
+  void _xor(Variable *Dest, Operand *Src0) {
+    Context.insert(InstX8632Xor::create(Func, Dest, Src0));
+  }
+
+  bool IsEbpBasedFrame;
+  int32_t FrameSizeLocals;
+  int32_t LocalsSizeBytes;
+  llvm::SmallBitVector TypeToRegisterSet[IceType_NUM];
+  llvm::SmallBitVector ScratchRegs;
+  llvm::SmallBitVector RegsUsed;
+  SizeT NextLabelNumber;
+  bool ComputedLiveRanges;
+  VarList PhysicalRegisters;
+  static IceString RegNames[];
+
+private:
+  TargetX8632(const TargetX8632 &) LLVM_DELETED_FUNCTION;
+  TargetX8632 &operator=(const TargetX8632 &) LLVM_DELETED_FUNCTION;
+  virtual ~TargetX8632() {}
+};
+
+} // end of namespace Ice
+
+#endif // SUBZERO_SRC_ICETARGETLOWERINGX8632_H