Add constant blinding/pooling option for X8632 code translation

src/IceTargetLoweringX8632.cpp

 //===- subzero/src/IceTargetLoweringX8632.cpp - x86-32 lowering -----------===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
 // This file implements the TargetLoweringX8632 class, which
@@ skipping 228 matching lines @@
 #undef X
 // Repeat the static asserts with respect to the high-level table
 // entries in case the high-level table has extra entries.
 #define X(tag, size, align, elts, elty, str)                                   \
   static_assert(_table1_##tag == _table2_##tag,                                \
                 "Inconsistency between ICETYPEX8632_TABLE and ICETYPE_TABLE");
 ICETYPE_TABLE
 #undef X
 } // end of namespace dummy3
 
+// A helper class to ease the settings of RandomizationPoolingPause
+// to disable constant blinding or pooling for some translation phases.
+class BoolFlagSaver {
+  BoolFlagSaver() = delete;
+  BoolFlagSaver(const BoolFlagSaver &) = delete;
+  BoolFlagSaver &operator=(const BoolFlagSaver &) = delete;
+
+public:
+  BoolFlagSaver(bool &F, bool NewValue) : OldValue(F), Flag(F) { F = NewValue; }
+  ~BoolFlagSaver() { Flag = OldValue; }
+
+private:
+  const bool OldValue;
+  bool &Flag;
+};
+
 } // end of anonymous namespace
 
 BoolFoldingEntry::BoolFoldingEntry(Inst *I)
     : Instr(I), IsComplex(BoolFolding::hasComplexLowering(I)), IsLiveOut(true),
       NumUses(0) {}
 
 BoolFolding::BoolFoldingProducerKind
 BoolFolding::getProducerKind(const Inst *Instr) {
   if (llvm::isa<InstIcmp>(Instr)) {
     if (Instr->getSrc(0)->getType() != IceType_i64)
@@ skipping 130 matching lines @@
   }
 }
 
 void TargetX8632::initNodeForLowering(CfgNode *Node) {
   FoldingInfo.init(Node);
   FoldingInfo.dump(Func);
 }
 
 TargetX8632::TargetX8632(Cfg *Func)
     : TargetLowering(Func), InstructionSet(X86InstructionSet::Begin),
-      IsEbpBasedFrame(false), NeedsStackAlignment(false),
-      SpillAreaSizeBytes(0) {
+      IsEbpBasedFrame(false), NeedsStackAlignment(false), SpillAreaSizeBytes(0),
+      RandomizationPoolingPaused(false) {
   static_assert((X86InstructionSet::End - X86InstructionSet::Begin) ==
                     (TargetInstructionSet::X86InstructionSet_End -
                      TargetInstructionSet::X86InstructionSet_Begin),
                 "X86InstructionSet range different from TargetInstructionSet");
   if (Func->getContext()->getFlags().getTargetInstructionSet() !=
       TargetInstructionSet::BaseInstructionSet) {
     InstructionSet = static_cast<X86InstructionSet>(
         (Func->getContext()->getFlags().getTargetInstructionSet() -
          TargetInstructionSet::X86InstructionSet_Begin) +
         X86InstructionSet::Begin);
@@ skipping 74 matching lines @@
     return;
 
   // TODO: It should be sufficient to use the fastest liveness
   // calculation, i.e. livenessLightweight().  However, for some
   // reason that slows down the rest of the translation.  Investigate.
   Func->liveness(Liveness_Basic);
   if (Func->hasError())
     return;
   Func->dump("After x86 address mode opt");
 
-  doLoadOpt();
+  // Disable constant blinding or pooling for load optimization.
+  {
+    BoolFlagSaver B(RandomizationPoolingPaused, true);
+    doLoadOpt();
+  }
   Func->genCode();
   if (Func->hasError())
     return;
   Func->dump("After x86 codegen");
 
   // Register allocation.  This requires instruction renumbering and
   // full liveness analysis.
   Func->renumberInstructions();
   if (Func->hasError())
     return;
   Func->liveness(Liveness_Intervals);
   if (Func->hasError())
     return;
   // Validate the live range computations.  The expensive validation
   // call is deliberately only made when assertions are enabled.
   assert(Func->validateLiveness());
   // The post-codegen dump is done here, after liveness analysis and
   // associated cleanup, to make the dump cleaner and more useful.
   Func->dump("After initial x8632 codegen");
   Func->getVMetadata()->init(VMK_All);
   regAlloc(RAK_Global);
   if (Func->hasError())
     return;
   Func->dump("After linear scan regalloc");
 
   if (Ctx->getFlags().getPhiEdgeSplit()) {
-    Func->advancedPhiLowering();
+    // We need to pause constant blinding or pooling during advanced
+    // phi lowering, unless the lowering assignment has a physical
+    // register for the dest Variable.
+    {
+      BoolFlagSaver B(RandomizationPoolingPaused, true);
+      Func->advancedPhiLowering();
+    }
     Func->dump("After advanced Phi lowering");
   }
 
   // Stack frame mapping.
   Func->genFrame();
   if (Func->hasError())
     return;
   Func->dump("After stack frame mapping");
 
   Func->contractEmptyNodes();
@@ skipping 371 matching lines @@
     return RegNames[RegNum];
   }
 }
 
 void TargetX8632::emitVariable(const Variable *Var) const {
   Ostream &Str = Ctx->getStrEmit();
   if (Var->hasReg()) {
     Str << "%" << getRegName(Var->getRegNum(), Var->getType());
     return;
   }
-  if (Var->getWeight().isInf())
+  if (Var->getWeight().isInf()) {
     llvm_unreachable("Infinite-weight Variable has no register assigned");
+  }
   int32_t Offset = Var->getStackOffset();
   if (!hasFramePointer())
     Offset += getStackAdjustment();
   if (Offset)
     Str << Offset;
   const Type FrameSPTy = IceType_i32;
   Str << "(%" << getRegName(getFrameOrStackReg(), FrameSPTy) << ")";
 }
 
 X8632::Address TargetX8632::stackVarToAsmOperand(const Variable *Var) const {
   if (Var->hasReg())
     llvm_unreachable("Stack Variable has a register assigned");
-  if (Var->getWeight().isInf())
+  if (Var->getWeight().isInf()) {
     llvm_unreachable("Infinite-weight Variable has no register assigned");
+  }
   int32_t Offset = Var->getStackOffset();
   if (!hasFramePointer())
     Offset += getStackAdjustment();
   return X8632::Address(RegX8632::getEncodedGPR(getFrameOrStackReg()), Offset);
 }
 
 void TargetX8632::lowerArguments() {
   VarList &Args = Func->getArgs();
   // The first four arguments of vector type, regardless of their
   // position relative to the other arguments in the argument list, are
@@ skipping 370 matching lines @@
 Operand *TargetX8632::loOperand(Operand *Operand) {
   assert(Operand->getType() == IceType_i64 ||
          Operand->getType() == IceType_f64);
   if (Operand->getType() != IceType_i64 && Operand->getType() != IceType_f64)
     return Operand;
   if (Variable *Var = llvm::dyn_cast<Variable>(Operand)) {
     split64(Var);
     return Var->getLo();
   }
   if (ConstantInteger64 *Const = llvm::dyn_cast<ConstantInteger64>(Operand)) {
-    return Ctx->getConstantInt32(static_cast<uint32_t>(Const->getValue()));
+    ConstantInteger32 *ConstInt = llvm::dyn_cast<ConstantInteger32>(
+        Ctx->getConstantInt32(static_cast<int32_t>(Const->getValue())));
+    return legalize(ConstInt);
   }
   if (OperandX8632Mem *Mem = llvm::dyn_cast<OperandX8632Mem>(Operand)) {
-    return OperandX8632Mem::create(Func, IceType_i32, Mem->getBase(),
-                                   Mem->getOffset(), Mem->getIndex(),
-                                   Mem->getShift(), Mem->getSegmentRegister());
+    OperandX8632Mem *MemOperand = OperandX8632Mem::create(
+        Func, IceType_i32, Mem->getBase(), Mem->getOffset(), Mem->getIndex(),
+        Mem->getShift(), Mem->getSegmentRegister());
+    // Test if we should randomize or pool the offset, if so randomize it or
+    // pool it then create mem operand with the blinded/pooled constant.
+    // Otherwise, return the mem operand as ordinary mem operand.
+    return legalize(MemOperand);
   }
   llvm_unreachable("Unsupported operand type");
   return nullptr;
 }
 
 Operand *TargetX8632::hiOperand(Operand *Operand) {
   assert(Operand->getType() == IceType_i64 ||
          Operand->getType() == IceType_f64);
   if (Operand->getType() != IceType_i64 && Operand->getType() != IceType_f64)
     return Operand;
   if (Variable *Var = llvm::dyn_cast<Variable>(Operand)) {
     split64(Var);
     return Var->getHi();
   }
   if (ConstantInteger64 *Const = llvm::dyn_cast<ConstantInteger64>(Operand)) {
-    return Ctx->getConstantInt32(
-        static_cast<uint32_t>(Const->getValue() >> 32));
+    ConstantInteger32 *ConstInt = llvm::dyn_cast<ConstantInteger32>(
+        Ctx->getConstantInt32(static_cast<int32_t>(Const->getValue() >> 32)));
+    // check if we need to blind/pool the constant
+    return legalize(ConstInt);
   }
   if (OperandX8632Mem *Mem = llvm::dyn_cast<OperandX8632Mem>(Operand)) {
     Constant *Offset = Mem->getOffset();
     if (Offset == nullptr) {
       Offset = Ctx->getConstantInt32(4);
     } else if (ConstantInteger32 *IntOffset =
                    llvm::dyn_cast<ConstantInteger32>(Offset)) {
       Offset = Ctx->getConstantInt32(4 + IntOffset->getValue());
     } else if (ConstantRelocatable *SymOffset =
                    llvm::dyn_cast<ConstantRelocatable>(Offset)) {
       assert(!Utils::WouldOverflowAdd(SymOffset->getOffset(), 4));
       Offset =
           Ctx->getConstantSym(4 + SymOffset->getOffset(), SymOffset->getName(),
                               SymOffset->getSuppressMangling());
     }
-    return OperandX8632Mem::create(Func, IceType_i32, Mem->getBase(), Offset,
-                                   Mem->getIndex(), Mem->getShift(),
-                                   Mem->getSegmentRegister());
+    OperandX8632Mem *MemOperand = OperandX8632Mem::create(
+        Func, IceType_i32, Mem->getBase(), Offset, Mem->getIndex(),
+        Mem->getShift(), Mem->getSegmentRegister());
+    // Test if the Offset is an eligible i32 constants for randomization and
+    // pooling. Blind/pool it if it is. Otherwise return as oridinary mem
+    // operand.
+    return legalize(MemOperand);
   }
   llvm_unreachable("Unsupported operand type");
   return nullptr;
 }
 
 llvm::SmallBitVector TargetX8632::getRegisterSet(RegSetMask Include,
                                                  RegSetMask Exclude) const {
   llvm::SmallBitVector Registers(RegX8632::Reg_NUM);
 
 #define X(val, encode, name, name16, name8, scratch, preserved, stackptr,      \
@@ skipping 165 matching lines @@
   Variable *Dest = Inst->getDest();
   Operand *Src0 = legalize(Inst->getSrc(0));
   Operand *Src1 = legalize(Inst->getSrc(1));
   if (Inst->isCommutative()) {
     if (!llvm::isa<Variable>(Src0) && llvm::isa<Variable>(Src1))
       std::swap(Src0, Src1);
     if (llvm::isa<Constant>(Src0) && !llvm::isa<Constant>(Src1))
       std::swap(Src0, Src1);
   }
   if (Dest->getType() == IceType_i64) {
+    // These helper-call-involved instructions are lowered in this
+    // separate switch. This is because loOperand() and hiOperand()
+    // may insert redundant instructions for constant blinding and
+    // pooling. Such redundant instructions will fail liveness analysis
+    // under -Om1 setting. And, actually these arguments do not need
+    // to be processed with loOperand() and hiOperand() to be used.
+    switch (Inst->getOp()) {
+    case InstArithmetic::Udiv: {
+      const SizeT MaxSrcs = 2;
+      InstCall *Call = makeHelperCall(H_udiv_i64, Dest, MaxSrcs);
+      Call->addArg(Inst->getSrc(0));
+      Call->addArg(Inst->getSrc(1));
+      lowerCall(Call);
+      return;
+    }
+    case InstArithmetic::Sdiv: {
+      const SizeT MaxSrcs = 2;
+      InstCall *Call = makeHelperCall(H_sdiv_i64, Dest, MaxSrcs);
+      Call->addArg(Inst->getSrc(0));
+      Call->addArg(Inst->getSrc(1));
+      lowerCall(Call);
+      return;
+    }
+    case InstArithmetic::Urem: {
+      const SizeT MaxSrcs = 2;
+      InstCall *Call = makeHelperCall(H_urem_i64, Dest, MaxSrcs);
+      Call->addArg(Inst->getSrc(0));
+      Call->addArg(Inst->getSrc(1));
+      lowerCall(Call);
+      return;
+    }
+    case InstArithmetic::Srem: {
+      const SizeT MaxSrcs = 2;
+      InstCall *Call = makeHelperCall(H_srem_i64, Dest, MaxSrcs);
+      Call->addArg(Inst->getSrc(0));
+      Call->addArg(Inst->getSrc(1));
+      lowerCall(Call);
+      return;
+    }
+    default:
+      break;
+    }
+
     Variable *DestLo = llvm::cast<Variable>(loOperand(Dest));
     Variable *DestHi = llvm::cast<Variable>(hiOperand(Dest));
     Operand *Src0Lo = loOperand(Src0);
     Operand *Src0Hi = hiOperand(Src0);
     Operand *Src1Lo = loOperand(Src1);
     Operand *Src1Hi = hiOperand(Src1);
     Variable *T_Lo = nullptr, *T_Hi = nullptr;
     switch (Inst->getOp()) {
     case InstArithmetic::_num:
       llvm_unreachable("Unknown arithmetic operator");
@@ skipping 169 matching lines @@
       // T_2 and T_3 are being assigned again because of the
       // intra-block control flow, so T_2 needs the _mov_nonkillable
       // variant to avoid liveness problems.  T_3 doesn't need special
       // treatment because it is reassigned via _sar instead of _mov.
       _mov_nonkillable(T_2, T_3);
       _sar(T_3, SignExtend);
       Context.insert(Label);
       _mov(DestLo, T_2);
       _mov(DestHi, T_3);
     } break;
-    case InstArithmetic::Udiv: {
-      const SizeT MaxSrcs = 2;
-      InstCall *Call = makeHelperCall(H_udiv_i64, Dest, MaxSrcs);
-      Call->addArg(Inst->getSrc(0));
-      Call->addArg(Inst->getSrc(1));
-      lowerCall(Call);
-    } break;
-    case InstArithmetic::Sdiv: {
-      const SizeT MaxSrcs = 2;
-      InstCall *Call = makeHelperCall(H_sdiv_i64, Dest, MaxSrcs);
-      Call->addArg(Inst->getSrc(0));
-      Call->addArg(Inst->getSrc(1));
-      lowerCall(Call);
-    } break;
-    case InstArithmetic::Urem: {
-      const SizeT MaxSrcs = 2;
-      InstCall *Call = makeHelperCall(H_urem_i64, Dest, MaxSrcs);
-      Call->addArg(Inst->getSrc(0));
-      Call->addArg(Inst->getSrc(1));
-      lowerCall(Call);
-    } break;
-    case InstArithmetic::Srem: {
-      const SizeT MaxSrcs = 2;
-      InstCall *Call = makeHelperCall(H_srem_i64, Dest, MaxSrcs);
-      Call->addArg(Inst->getSrc(0));
-      Call->addArg(Inst->getSrc(1));
-      lowerCall(Call);
-    } break;
     case InstArithmetic::Fadd:
     case InstArithmetic::Fsub:
     case InstArithmetic::Fmul:
     case InstArithmetic::Fdiv:
     case InstArithmetic::Frem:
       llvm_unreachable("FP instruction with i64 type");
       break;
+    case InstArithmetic::Udiv:
+    case InstArithmetic::Sdiv:
+    case InstArithmetic::Urem:
+    case InstArithmetic::Srem:
+      llvm_unreachable("Call-helper-involved instruction for i64 type \
+                       should has already been handled before");

[Jim Stichnoth, 2015/06/20 17:42:16]

should have

+      break;
     }
     return;
   }
   if (isVectorType(Dest->getType())) {
     // TODO: Trap on integer divide and integer modulo by zero.
     // See: https://code.google.com/p/nativeclient/issues/detail?id=3899
     if (llvm::isa<OperandX8632Mem>(Src1))
       Src1 = legalizeToVar(Src1);
     switch (Inst->getOp()) {
     case InstArithmetic::_num:
@@ skipping 374 matching lines @@
     Operand *Src0Hi = hiOperand(Src0);
     Variable *DestLo = llvm::cast<Variable>(loOperand(Dest));
     Variable *DestHi = llvm::cast<Variable>(hiOperand(Dest));
     Variable *T_Lo = nullptr, *T_Hi = nullptr;
     _mov(T_Lo, Src0Lo);
     _mov(DestLo, T_Lo);
     _mov(T_Hi, Src0Hi);
     _mov(DestHi, T_Hi);
   } else {
     Operand *RI;
-    if (Dest->hasReg())
+    if (Dest->hasReg()) {
       // If Dest already has a physical register, then legalize the
       // Src operand into a Variable with the same register
       // assignment.  This is mostly a workaround for advanced phi
       // lowering's ad-hoc register allocation which assumes no
       // register allocation is needed when at least one of the
       // operands is non-memory.
-      RI = legalize(Src0, Legal_Reg, Dest->getRegNum());
-    else
+
+      // If we have a physical register for the dest variable, we can
+      // enable our constant blinding or pooling again. Note this is
+      // only for advancedPhiLowering(), the flag flip should leave
+      // no other side effect.
+      {
+        BoolFlagSaver B(RandomizationPoolingPaused, false);
+        RI = legalize(Src0, Legal_Reg, Dest->getRegNum());
+      }
+    } else {
       // If Dest could be a stack operand, then RI must be a physical
       // register or a scalar integer immediate.
       RI = legalize(Src0, Legal_Reg | Legal_Imm);
+    }
     if (isVectorType(Dest->getType()))
       _movp(Dest, RI);
     else
       _mov(Dest, RI);
   }
 }
 
 void TargetX8632::lowerBr(const InstBr *Inst) {
   if (Inst->isUnconditional()) {
     _br(Inst->getTargetUnconditional());
@@ skipping 2540 matching lines @@
   } else {
     TargetLowering::lowerOther(Instr);
   }
 }
 
 // Turn an i64 Phi instruction into a pair of i32 Phi instructions, to
 // preserve integrity of liveness analysis.  Undef values are also
 // turned into zeroes, since loOperand() and hiOperand() don't expect
 // Undef input.
 void TargetX8632::prelowerPhis() {
+  // Pause constant blinding or pooling, blinding or pooling will be done later
+  // during phi lowering assignments
+  BoolFlagSaver B(RandomizationPoolingPaused, true);
+
   CfgNode *Node = Context.getNode();
   for (Inst &I : Node->getPhis()) {
     auto Phi = llvm::dyn_cast<InstPhi>(&I);
     if (Phi->isDeleted())
       continue;
     Variable *Dest = Phi->getDest();
     if (Dest->getType() == IceType_i64) {
       Variable *DestLo = llvm::cast<Variable>(loOperand(Dest));
       Variable *DestHi = llvm::cast<Variable>(hiOperand(Dest));
       InstPhi *PhiLo = InstPhi::create(Func, Phi->getSrcSize(), DestLo);
@@ skipping 79 matching lines @@
   // assignment, add Dest to the set of available registers, and
   // remove Src from the set of available registers.  Iteration is
   // done backwards to enable incremental updates of the available
   // register set, and the lowered instruction numbers may be out of
   // order, but that can be worked around by renumbering the block
   // afterwards if necessary.
   for (const Inst &I : reverse_range(Assignments)) {
     Context.rewind();
     auto Assign = llvm::dyn_cast<InstAssign>(&I);
     Variable *Dest = Assign->getDest();
+
+    // If the source operand is ConstantUndef, do not legalize it.
+    // In function test_split_undef_int_vec, the advanced phi
+    // lowering process will find an assignment of undefined
+    // vector. This vector, as the Src here, will crash if it
+    // go through legalize(). legalize() will create new variable
+    // with makeVectorOfZeros(), but this new variable will be
+    // assigned a stack slot. This will fail the assertion in
+    // IceInstX8632.cpp:789, as XmmEmitterRegOp() complain:
+    // Var->hasReg() fails. Note this failure is irrelevant to
+    // randomization or pooling of constants.
+    // So, we do not call legalize() to add pool label for the
+    // src operands of phi assignment instructions.
+    // Instead, we manually add pool label for constant float and
+    // constant double values here.
+    // Note going through legalize() does not affect the testing
+    // results of SPEC2K and xtests.
     Operand *Src = Assign->getSrc(0);
+    if (!llvm::isa<ConstantUndef>(Assign->getSrc(0))) {
+      Src = legalize(Src);
+    }
+
     Variable *SrcVar = llvm::dyn_cast<Variable>(Src);
     // Use normal assignment lowering, except lower mem=mem specially
     // so we can register-allocate at the same time.
     if (!isMemoryOperand(Dest) || !isMemoryOperand(Src)) {
       lowerAssign(Assign);
     } else {
       assert(Dest->getType() == Src->getType());
       const llvm::SmallBitVector &RegsForType =
           getRegisterSetForType(Dest->getType());
       llvm::SmallBitVector AvailRegsForType = RegsForType & Available;
@@ skipping 155 matching lines @@
   // Assert that a physical register is allowed.  To date, all calls
   // to legalize() allow a physical register.  If a physical register
   // needs to be explicitly disallowed, then new code will need to be
   // written to force a spill.
   assert(Allowed & Legal_Reg);
   // If we're asking for a specific physical register, make sure we're
   // not allowing any other operand kinds.  (This could be future
   // work, e.g. allow the shl shift amount to be either an immediate
   // or in ecx.)
   assert(RegNum == Variable::NoRegister || Allowed == Legal_Reg);
+
   if (auto Mem = llvm::dyn_cast<OperandX8632Mem>(From)) {
     // Before doing anything with a Mem operand, we need to ensure
     // that the Base and Index components are in physical registers.
     Variable *Base = Mem->getBase();
     Variable *Index = Mem->getIndex();
     Variable *RegBase = nullptr;
     Variable *RegIndex = nullptr;
     if (Base) {
       RegBase = legalizeToVar(Base);
     }
     if (Index) {
       RegIndex = legalizeToVar(Index);
     }
     if (Base != RegBase || Index != RegIndex) {
-      From =
+      Mem =
           OperandX8632Mem::create(Func, Ty, RegBase, Mem->getOffset(), RegIndex,
                                   Mem->getShift(), Mem->getSegmentRegister());
     }
 
+    // For all Memory Operands, we do randomization/pooling here
+    From = randomizeOrPoolImmediate(Mem);
+
     if (!(Allowed & Legal_Mem)) {
       From = copyToReg(From, RegNum);
     }
     return From;
   }
-  if (llvm::isa<Constant>(From)) {
-    if (llvm::isa<ConstantUndef>(From)) {
+  if (auto *Const = llvm::dyn_cast<Constant>(From)) {
+    if (llvm::isa<ConstantUndef>(Const)) {
       // Lower undefs to zero.  Another option is to lower undefs to an
       // uninitialized register; however, using an uninitialized register
       // results in less predictable code.
       //
       // If in the future the implementation is changed to lower undef
       // values to uninitialized registers, a FakeDef will be needed:
       //     Context.insert(InstFakeDef::create(Func, Reg));
       // This is in order to ensure that the live range of Reg is not
       // overestimated.  If the constant being lowered is a 64 bit value,
       // then the result should be split and the lo and hi components will
       // need to go in uninitialized registers.
       if (isVectorType(Ty))
         return makeVectorOfZeros(Ty, RegNum);
       From = Ctx->getConstantZero(Ty);

[Jim Stichnoth, 2015/06/20 17:42:16]

I think you need to reset Const as well, e.g.:
  Const = Ctx->getConstantZero(Ty);
  From = Const;

     }
     // There should be no constants of vector type (other than undef).
     assert(!isVectorType(Ty));
+
+    // If the operand is an 32 bit constant integer, we should check
+    // whether we need to randomize it or pool it.
+    if (ConstantInteger32 *C = llvm::dyn_cast<ConstantInteger32>(Const)) {
+      Operand *NewConst = randomizeOrPoolImmediate(C, RegNum);
+      if (NewConst != Const) {
+        return NewConst;
+      }
+    }
+
     // Convert a scalar floating point constant into an explicit
     // memory operand.
     if (isScalarFloatingType(Ty)) {
       Variable *Base = nullptr;
       std::string Buffer;
       llvm::raw_string_ostream StrBuf(Buffer);
       llvm::cast<Constant>(From)->emitPoolLabel(StrBuf);
+      llvm::cast<Constant>(From)->setShouldBePooled(true);
       Constant *Offset = Ctx->getConstantSym(0, StrBuf.str(), true);
       From = OperandX8632Mem::create(Func, Ty, Base, Offset);
     }
     bool NeedsReg = false;
     if (!(Allowed & Legal_Imm) && !isScalarFloatingType(Ty))
       // Immediate specifically not allowed
       NeedsReg = true;
     if (!(Allowed & Legal_Mem) && isScalarFloatingType(Ty))
       // On x86, FP constants are lowered to mem operands.
       NeedsReg = true;
@@ skipping 36 matching lines @@
   bool IsSrc1ImmOrReg = false;
   if (llvm::isa<Constant>(Src1)) {
     IsSrc1ImmOrReg = true;
   } else if (Variable *Var = llvm::dyn_cast<Variable>(Src1)) {
     if (Var->hasReg())
       IsSrc1ImmOrReg = true;
   }
   return legalize(Src0, IsSrc1ImmOrReg ? (Legal_Reg | Legal_Mem) : Legal_Reg);
 }
 
-OperandX8632Mem *TargetX8632::formMemoryOperand(Operand *Operand, Type Ty,
+OperandX8632Mem *TargetX8632::formMemoryOperand(Operand *Opnd, Type Ty,
                                                 bool DoLegalize) {
-  OperandX8632Mem *Mem = llvm::dyn_cast<OperandX8632Mem>(Operand);
+  OperandX8632Mem *Mem = llvm::dyn_cast<OperandX8632Mem>(Opnd);
   // It may be the case that address mode optimization already creates
   // an OperandX8632Mem, so in that case it wouldn't need another level
   // of transformation.
   if (!Mem) {
-    Variable *Base = llvm::dyn_cast<Variable>(Operand);
-    Constant *Offset = llvm::dyn_cast<Constant>(Operand);
+    Variable *Base = llvm::dyn_cast<Variable>(Opnd);
+    Constant *Offset = llvm::dyn_cast<Constant>(Opnd);
     assert(Base || Offset);
     if (Offset) {
-      // Make sure Offset is not undef.
-      Offset = llvm::cast<Constant>(legalize(Offset));
+      // During memory operand building, we do not blind or pool
+      // the constant offset, we will work on the whole memory
+      // operand later as one entity later, this save one instruction.
+      // By turning blinding and pooling off, we guarantee
+      // legalize(Offset) will return a constant*.
+      {
+        BoolFlagSaver B(RandomizationPoolingPaused, true);
+
+        Offset = llvm::cast<Constant>(legalize(Offset));
+      }
+
       assert(llvm::isa<ConstantInteger32>(Offset) ||
              llvm::isa<ConstantRelocatable>(Offset));
     }
     Mem = OperandX8632Mem::create(Func, Ty, Base, Offset);
   }
-  return llvm::cast<OperandX8632Mem>(DoLegalize ? legalize(Mem) : Mem);
+  // Do legalization, which contains randomization/pooling
+  // or do randomization/pooling.
+  return llvm::cast<OperandX8632Mem>(
+      DoLegalize ? legalize(Mem) : randomizeOrPoolImmediate(Mem));
 }
 
 Variable *TargetX8632::makeReg(Type Type, int32_t RegNum) {
   // There aren't any 64-bit integer registers for x86-32.
   assert(Type != IceType_i64);
   Variable *Reg = Func->makeVariable(Type);
   if (RegNum == Variable::NoRegister)
     Reg->setWeightInfinite();
   else
     Reg->setRegNum(RegNum);
@@ skipping 144 matching lines @@
   typedef ConstantDouble IceType;
   static const Type Ty = IceType_f64;
   static const char *TypeName;
   static const char *AsmTag;
   static const char *PrintfString;
 };
 const char *PoolTypeConverter<double>::TypeName = "double";
 const char *PoolTypeConverter<double>::AsmTag = ".quad";
 const char *PoolTypeConverter<double>::PrintfString = "0x%llx";
 
+// Add converter for int type constant pooling
+template <> struct PoolTypeConverter<uint32_t> {
+  typedef uint32_t PrimitiveIntType;
+  typedef ConstantInteger32 IceType;
+  static const Type Ty = IceType_i32;
+  static const char *TypeName;
+  static const char *AsmTag;
+  static const char *PrintfString;
+};
+const char *PoolTypeConverter<uint32_t>::TypeName = "i32";
+const char *PoolTypeConverter<uint32_t>::AsmTag = ".long";
+const char *PoolTypeConverter<uint32_t>::PrintfString = "0x%x";
+
+// Add converter for int type constant pooling
+template <> struct PoolTypeConverter<uint16_t> {
+  typedef uint32_t PrimitiveIntType;
+  typedef ConstantInteger32 IceType;
+  static const Type Ty = IceType_i16;
+  static const char *TypeName;
+  static const char *AsmTag;
+  static const char *PrintfString;
+};
+const char *PoolTypeConverter<uint16_t>::TypeName = "i16";
+const char *PoolTypeConverter<uint16_t>::AsmTag = ".short";
+const char *PoolTypeConverter<uint16_t>::PrintfString = "0x%x";
+
+// Add converter for int type constant pooling
+template <> struct PoolTypeConverter<uint8_t> {
+  typedef uint32_t PrimitiveIntType;
+  typedef ConstantInteger32 IceType;
+  static const Type Ty = IceType_i8;
+  static const char *TypeName;
+  static const char *AsmTag;
+  static const char *PrintfString;
+};
+const char *PoolTypeConverter<uint8_t>::TypeName = "i8";
+const char *PoolTypeConverter<uint8_t>::AsmTag = ".byte";
+const char *PoolTypeConverter<uint8_t>::PrintfString = "0x%x";
+
 template <typename T>
 void TargetDataX8632::emitConstantPool(GlobalContext *Ctx) {
   if (!ALLOW_DUMP)
     return;
   Ostream &Str = Ctx->getStrEmit();
   Type Ty = T::Ty;
   SizeT Align = typeAlignInBytes(Ty);
   ConstantList Pool = Ctx->getConstantPool(Ty);
 
   Str << "\t.section\t.rodata.cst" << Align << ",\"aM\",@progbits," << Align
       << "\n";
   Str << "\t.align\t" << Align << "\n";
   for (Constant *C : Pool) {
+    if (!C->getShouldBePooled())
+      continue;
     typename T::IceType *Const = llvm::cast<typename T::IceType>(C);
     typename T::IceType::PrimType Value = Const->getValue();
     // Use memcpy() to copy bits from Value into RawValue in a way
     // that avoids breaking strict-aliasing rules.
     typename T::PrimitiveIntType RawValue;
     memcpy(&RawValue, &Value, sizeof(Value));
     char buf[30];
     int CharsPrinted =
         snprintf(buf, llvm::array_lengthof(buf), T::PrintfString, RawValue);
     assert(CharsPrinted >= 0 &&
            (size_t)CharsPrinted < llvm::array_lengthof(buf));
     (void)CharsPrinted; // avoid warnings if asserts are disabled
     Const->emitPoolLabel(Str);
     Str << ":\n\t" << T::AsmTag << "\t" << buf << "\t# " << T::TypeName << " "
         << Value << "\n";
   }
 }
 
 void TargetDataX8632::lowerConstants() {
   if (Ctx->getFlags().getDisableTranslation())
     return;
   // No need to emit constants from the int pool since (for x86) they
   // are embedded as immediates in the instructions, just emit float/double.
   switch (Ctx->getFlags().getOutFileType()) {
   case FT_Elf: {
     ELFObjectWriter *Writer = Ctx->getObjectWriter();
+
+    Writer->writeConstantPool<ConstantInteger32>(IceType_i8);
+    Writer->writeConstantPool<ConstantInteger32>(IceType_i16);
+    Writer->writeConstantPool<ConstantInteger32>(IceType_i32);
+
     Writer->writeConstantPool<ConstantFloat>(IceType_f32);
     Writer->writeConstantPool<ConstantDouble>(IceType_f64);
   } break;
   case FT_Asm:
   case FT_Iasm: {
     OstreamLocker L(Ctx);
+
+    emitConstantPool<PoolTypeConverter<uint8_t>>(Ctx);
+    emitConstantPool<PoolTypeConverter<uint16_t>>(Ctx);
+    emitConstantPool<PoolTypeConverter<uint32_t>>(Ctx);
+
     emitConstantPool<PoolTypeConverter<float>>(Ctx);
     emitConstantPool<PoolTypeConverter<double>>(Ctx);
   } break;
   }
 }
 
 TargetHeaderX8632::TargetHeaderX8632(GlobalContext *Ctx)
     : TargetHeaderLowering(Ctx) {}
 
+// Randomize or pool an Immediate.
+Operand *TargetX8632::randomizeOrPoolImmediate(Constant *Immediate,
+                                               int32_t RegNum) {
+  assert(llvm::isa<ConstantInteger32>(Immediate) ||
+         llvm::isa<ConstantRelocatable>(Immediate));
+  if (Ctx->getFlags().getRandomizeAndPoolImmediatesOption() == RPI_None ||
+      RandomizationPoolingPaused == true) {
+    // Immediates randomization/pooling off or paused
+    return Immediate;
+  }
+  if (Immediate->shouldBeRandomizedOrPooled(Ctx)) {
+    Ctx->statsUpdateRPImms();
+    if (Ctx->getFlags().getRandomizeAndPoolImmediatesOption() ==
+        RPI_Randomize) {
+      // blind the constant
+      // FROM:
+      //  imm
+      // TO:
+      //  insert: mov imm+cookie, Reg
+      //  insert: lea -cookie[Reg], Reg
+      //  => Reg
+      // If we have already assigned a phy register, we must come from
+      // andvancedPhiLowering()=>lowerAssign(). In this case we should reuse
+      // the assigned register as this assignment is that start of its use-def
+      // chain. So we add RegNum argument here.
+      // Note we use 'lea' instruction instead of 'xor' to avoid affecting
+      // the flags.
+      Variable *Reg = makeReg(IceType_i32, RegNum);
+      ConstantInteger32 *Integer = llvm::cast<ConstantInteger32>(Immediate);
+      uint32_t Value = Integer->getValue();
+      uint32_t Cookie = Ctx->getRandomizationCookie();
+      _mov(Reg, Ctx->getConstantInt(IceType_i32, Cookie + Value));
+      Constant *Offset = Ctx->getConstantInt(IceType_i32, 0 - Cookie);
+      _lea(Reg,
+           OperandX8632Mem::create(Func, IceType_i32, Reg, Offset, nullptr, 0));
+      // make sure liveness analysis won't kill this variable, otherwise a
+      // liveness
+      // assertion will be triggered.
+      _set_dest_nonkillable();
+      if (Immediate->getType() != IceType_i32) {
+        Variable *TruncReg = makeReg(Immediate->getType(), RegNum);
+        _mov(TruncReg, Reg);
+        return TruncReg;
+      }
+      return Reg;
+    }
+    if (Ctx->getFlags().getRandomizeAndPoolImmediatesOption() == RPI_Pool) {
+      // pool the constant
+      // FROM:
+      //  imm
+      // TO:
+      //  insert: mov $label, Reg
+      //  => Reg
+      assert(Ctx->getFlags().getRandomizeAndPoolImmediatesOption() == RPI_Pool);
+      Immediate->setShouldBePooled(true);
+      // if we have already assigned a phy register, we must come from
+      // andvancedPhiLowering()=>lowerAssign(). In this case we should reuse
+      // the assigned register as this assignment is that start of its use-def
+      // chain. So we add RegNum argument here.
+      Variable *Reg = makeReg(Immediate->getType(), RegNum);
+      IceString Label;
+      llvm::raw_string_ostream Label_stream(Label);
+      Immediate->emitPoolLabel(Label_stream);
+      const RelocOffsetT Offset = 0;
+      const bool SuppressMangling = true;
+      Constant *Symbol =
+          Ctx->getConstantSym(Offset, Label_stream.str(), SuppressMangling);
+      OperandX8632Mem *MemOperand =
+          OperandX8632Mem::create(Func, Immediate->getType(), nullptr, Symbol);
+      _mov(Reg, MemOperand);
+      return Reg;
+    }
+    assert("Unsupported -randomize-pool-immediates option" && false);
+  }
+  // the constant Immediate is not eligible for blinding/pooling
+  return Immediate;
+}
+
+OperandX8632Mem *
+TargetX8632::randomizeOrPoolImmediate(OperandX8632Mem *MemOperand,
+                                      int32_t RegNum) {
+  assert(MemOperand);
+  if (Ctx->getFlags().getRandomizeAndPoolImmediatesOption() == RPI_None ||
+      RandomizationPoolingPaused == true) {
+    // immediates randomization/pooling is turned off
+    return MemOperand;
+  }
+
+  // If this memory operand is already a randommized one, we do
+  // not randomize it again.
+  if (MemOperand->getRandomize())
+    return MemOperand;
+
+  if (Constant *C = llvm::dyn_cast_or_null<Constant>(MemOperand->getOffset())) {
+    if (C->shouldBeRandomizedOrPooled(Ctx)) {
+      // The offset of this mem operand should be blinded or pooled
+      Ctx->statsUpdateRPImms();
+      if (Ctx->getFlags().getRandomizeAndPoolImmediatesOption() ==
+          RPI_Randomize) {
+        // blind the constant offset
+        // FROM:
+        //  offset[base, index, shift]
+        // TO:
+        //  insert: lea offset+cookie[base], RegTemp
+        //  => -cookie[RegTemp, index, shift]
+        uint32_t Value =
+            llvm::dyn_cast<ConstantInteger32>(MemOperand->getOffset())
+                ->getValue();
+        uint32_t Cookie = Ctx->getRandomizationCookie();
+        Constant *Mask1 = Ctx->getConstantInt(
+            MemOperand->getOffset()->getType(), Cookie + Value);
+        Constant *Mask2 =
+            Ctx->getConstantInt(MemOperand->getOffset()->getType(), 0 - Cookie);
+
+        OperandX8632Mem *TempMemOperand = OperandX8632Mem::create(
+            Func, MemOperand->getType(), MemOperand->getBase(), Mask1);
+        // If we have already assigned a physical register, we must come from
+        // advancedPhiLowering()=>lowerAssign(). In this case we should reuse
+        // the assigned register as this assignment is that start of its use-def
+        // chain. So we add RegNum argument here.
+        Variable *RegTemp = makeReg(MemOperand->getOffset()->getType(), RegNum);
+        _lea(RegTemp, TempMemOperand);
+        // As source operand doesn't use the dstreg, we don't need to add
+        // _set_dest_nonkillable().
+        // But if we use the same Dest Reg, that is, with RegNum
+        // assigned, we should add this _set_dest_nonkillable()
+        if (RegNum != Variable::NoRegister)
+          _set_dest_nonkillable();
+
+        OperandX8632Mem *NewMemOperand = OperandX8632Mem::create(
+            Func, MemOperand->getType(), RegTemp, Mask2, MemOperand->getIndex(),
+            MemOperand->getShift(), MemOperand->getSegmentRegister());
+
+        // Label this memory operand as randomize, so we won't randomize it
+        // again in case we call legalize() mutiple times on this memory
+        // operand.
+        NewMemOperand->setRandomized(true);
+        return NewMemOperand;
+      }
+      if (Ctx->getFlags().getRandomizeAndPoolImmediatesOption() == RPI_Pool) {
+        // pool the constant offset
+        // FROM:
+        //  offset[base, index, shift]
+        // TO:
+        //  insert: mov $label, RegTemp
+        //  insert: lea [base, RegTemp], RegTemp
+        //  =>[RegTemp, index, shift]
+        assert(Ctx->getFlags().getRandomizeAndPoolImmediatesOption() ==
+               RPI_Pool);
+        // Memory operand should never exist as source operands in phi
+        // lowering assignments, so there is no need to reuse any registers
+        // here. For phi lowering, we should not ask for new physical
+        // registers in general.
+        // However, if we do meet Memory Operand during phi lowering, we
+        // should not blind or pool the immediates for now.
+        if (RegNum != Variable::NoRegister)
+          return MemOperand;
+        Variable *RegTemp = makeReg(IceType_i32);
+        IceString Label;
+        llvm::raw_string_ostream Label_stream(Label);
+        MemOperand->getOffset()->emitPoolLabel(Label_stream);
+        MemOperand->getOffset()->setShouldBePooled(true);
+        const RelocOffsetT SymOffset = 0;
+        bool SuppressMangling = true;
+        Constant *Symbol = Ctx->getConstantSym(SymOffset, Label_stream.str(),
+                                               SuppressMangling);
+        OperandX8632Mem *SymbolOperand = OperandX8632Mem::create(
+            Func, MemOperand->getOffset()->getType(), nullptr, Symbol);
+        _mov(RegTemp, SymbolOperand);
+        // If we have a base variable here, we should add the lea instruction
+        // to add the value of the base variable to RegTemp. If there is no
+        // base variable, we won't need this lea instruction.
+        if (MemOperand->getBase()) {
+          OperandX8632Mem *CalculateOperand = OperandX8632Mem::create(
+              Func, MemOperand->getType(), MemOperand->getBase(), nullptr,
+              RegTemp, 0, MemOperand->getSegmentRegister());
+          _lea(RegTemp, CalculateOperand);
+          _set_dest_nonkillable();
+        }
+        OperandX8632Mem *NewMemOperand = OperandX8632Mem::create(
+            Func, MemOperand->getType(), RegTemp, nullptr,
+            MemOperand->getIndex(), MemOperand->getShift(),
+            MemOperand->getSegmentRegister());
+        return NewMemOperand;
+      }
+      assert("Unsupported -randomize-pool-immediates option" && false);
+    }
+  }
+  // the offset is not eligible for blinding or pooling, return the original
+  // mem operand
+  return MemOperand;
+}
+
 } // end of namespace Ice