Revert r11420 because Win32 compilation was broken.

TBR=danno@chromium.org
Review URL: https://chromiumcodereview.appspot.com/10190007

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11421 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/arm/lithium-arm.cc

@@ -1315,75 +1315,6 @@ LInstruction* LChunkBuilder::DoDiv(HDiv* instr) {
 }
 
 
-bool LChunkBuilder::HasMagicNumberForDivisor(int32_t divisor) {
-  uint32_t divisor_abs = abs(divisor);
-  // Dividing by 0, 1, and powers of 2 is easy.
-  // Note that IsPowerOf2(0) returns true;
-  ASSERT(IsPowerOf2(0) == true);
-  if (IsPowerOf2(divisor_abs)) return true;
-
-  // We have magic numbers for a few specific divisors.
-  // Details and proofs can be found in:
-  // - Hacker's Delight, Henry S. Warren, Jr.
-  // - The PowerPC Compiler Writer’s Guide
-  // and probably many others.
-  //
-  // We handle
-  //   <divisor with magic numbers> * <power of 2>
-  // but not
-  //   <divisor with magic numbers> * <other divisor with magic numbers>
-  int32_t power_of_2_factor =
-    CompilerIntrinsics::CountTrailingZeros(divisor_abs);
-  DivMagicNumbers magic_numbers =
-    DivMagicNumberFor(divisor_abs >> power_of_2_factor);
-  if (magic_numbers.M != InvalidDivMagicNumber.M) return true;
-
-  return false;
-}
-
-
-HValue* LChunkBuilder::SimplifiedDividendForMathFloorOfDiv(HValue* dividend) {
-  // A value with an integer representation does not need to be transformed.
-  if (dividend->representation().IsInteger32()) {
-    return dividend;
-  // A change from an integer32 can be replaced by the integer32 value.
-  } else if (dividend->IsChange() &&
-      HChange::cast(dividend)->from().IsInteger32()) {
-    return HChange::cast(dividend)->value();
-  }
-  return NULL;
-}
-
-
-HValue* LChunkBuilder::SimplifiedDivisorForMathFloorOfDiv(HValue* divisor) {
-  // Only optimize when we have magic numbers for the divisor.
-  // The standard integer division routine is usually slower than transitionning
-  // to VFP.
-  if (divisor->IsConstant() &&
-      HConstant::cast(divisor)->HasInteger32Value()) {
-    HConstant* constant_val = HConstant::cast(divisor);
-    int32_t int32_val = constant_val->Integer32Value();
-    if (LChunkBuilder::HasMagicNumberForDivisor(int32_val)) {
-      return constant_val->CopyToRepresentation(Representation::Integer32());
-    }
-  }
-  return NULL;
-}
-
-
-LInstruction* LChunkBuilder::DoMathFloorOfDiv(HMathFloorOfDiv* instr) {
-    HValue* right = instr->right();
-    LOperand* dividend = UseRegister(instr->left());
-    LOperand* divisor = UseRegisterOrConstant(right);
-    LOperand* remainder = TempRegister();
-    ASSERT(right->IsConstant() &&
-           HConstant::cast(right)->HasInteger32Value() &&
-           HasMagicNumberForDivisor(HConstant::cast(right)->Integer32Value()));
-    return AssignEnvironment(DefineAsRegister(
-          new LMathFloorOfDiv(dividend, divisor, remainder)));
-}
-
-
 LInstruction* LChunkBuilder::DoMod(HMod* instr) {
   if (instr->representation().IsInteger32()) {
     ASSERT(instr->left()->representation().IsInteger32());

src/arm/lithium-arm.h

@@ -132,7 +132,6 @@ class LCodeGen;
   V(LoadNamedField)                             \
   V(LoadNamedFieldPolymorphic)                  \
   V(LoadNamedGeneric)                           \
-  V(MathFloorOfDiv)                             \
   V(ModI)                                       \
   V(MulI)                                       \
   V(NumberTagD)                                 \
@@ -580,21 +579,6 @@ class LDivI: public LTemplateInstruction<1, 2, 0> {
 };
 
 
-class LMathFloorOfDiv: public LTemplateInstruction<1, 2, 1> {
- public:
-  LMathFloorOfDiv(LOperand* left,
-                  LOperand* right,
-                  LOperand* temp = NULL) {
-    inputs_[0] = left;
-    inputs_[1] = right;
-    temps_[0] = temp;
-  }
-
-  DECLARE_CONCRETE_INSTRUCTION(MathFloorOfDiv, "math-floor-of-div")
-  DECLARE_HYDROGEN_ACCESSOR(MathFloorOfDiv)
-};
-
-
 class LMulI: public LTemplateInstruction<1, 2, 1> {
  public:
   LMulI(LOperand* left, LOperand* right, LOperand* temp) {
@@ -2303,10 +2287,6 @@ class LChunkBuilder BASE_EMBEDDED {
   HYDROGEN_CONCRETE_INSTRUCTION_LIST(DECLARE_DO)
 #undef DECLARE_DO
 
-  static bool HasMagicNumberForDivisor(int32_t divisor);
-  static HValue* SimplifiedDividendForMathFloorOfDiv(HValue* val);
-  static HValue* SimplifiedDivisorForMathFloorOfDiv(HValue* val);
-
  private:
   enum Status {
     UNUSED,

src/arm/lithium-codegen-arm.cc

@@ -1034,100 +1034,6 @@ void LCodeGen::DoModI(LModI* instr) {
 }
 
 
-void LCodeGen::EmitSignedIntegerDivisionByConstant(
-    Register result,
-    Register dividend,
-    int32_t divisor,
-    Register remainder,
-    Register scratch,
-    LEnvironment* environment) {
-  ASSERT(!AreAliased(dividend, scratch, ip));
-  ASSERT(LChunkBuilder::HasMagicNumberForDivisor(divisor));
-
-  uint32_t divisor_abs = abs(divisor);
-
-  int32_t power_of_2_factor =
-    CompilerIntrinsics::CountTrailingZeros(divisor_abs);
-
-  switch (divisor_abs) {
-    case 0:
-      DeoptimizeIf(al, environment);
-      return;
-
-    case 1:
-      if (divisor > 0) {
-        __ Move(result, dividend);
-      } else {
-        __ rsb(result, dividend, Operand(0), SetCC);
-        DeoptimizeIf(vs, environment);
-      }
-      // Compute the remainder.
-      __ mov(remainder, Operand(0));
-      return;
-
-    default:
-      if (IsPowerOf2(divisor_abs)) {
-        // Branch and condition free code for integer division by a power
-        // of two.
-        int32_t power = WhichPowerOf2(divisor_abs);
-        if (power > 1) {
-          __ mov(scratch, Operand(dividend, ASR, power - 1));
-        }
-        __ add(scratch, dividend, Operand(scratch, LSR, 32 - power));
-        __ mov(result, Operand(scratch, ASR, power));
-        // Negate if necessary.
-        // We don't need to check for overflow because the case '-1' is
-        // handled separately.
-        if (divisor < 0) {
-          ASSERT(divisor != -1);
-          __ rsb(result, result, Operand(0));
-        }
-        // Compute the remainder.
-        if (divisor > 0) {
-          __ sub(remainder, dividend, Operand(result, LSL, power));
-        } else {
-          __ add(remainder, dividend, Operand(result, LSL, power));
-        }
-        return;
-      } else {
-        // Use magic numbers for a few specific divisors.
-        // Details and proofs can be found in:
-        // - Hacker's Delight, Henry S. Warren, Jr.
-        // - The PowerPC Compiler Writer’s Guide
-        // and probably many others.
-        //
-        // We handle
-        //   <divisor with magic numbers> * <power of 2>
-        // but not
-        //   <divisor with magic numbers> * <other divisor with magic numbers>
-        DivMagicNumbers magic_numbers =
-          DivMagicNumberFor(divisor_abs >> power_of_2_factor);
-        // Branch and condition free code for integer division by a power
-        // of two.
-        const int32_t M = magic_numbers.M;
-        const int32_t s = magic_numbers.s + power_of_2_factor;
-
-        __ mov(ip, Operand(M));
-        __ smull(ip, scratch, dividend, ip);
-        if (M < 0) {
-          __ add(scratch, scratch, Operand(dividend));
-        }
-        if (s > 0) {
-          __ mov(scratch, Operand(scratch, ASR, s));
-        }
-        __ add(result, scratch, Operand(dividend, LSR, 31));
-        if (divisor < 0) __ rsb(result, result, Operand(0));
-        // Compute the remainder.
-        __ mov(ip, Operand(divisor));
-        // This sequence could be replaced with 'mls' when
-        // it gets implemented.
-        __ mul(scratch, result, ip);
-        __ sub(remainder, dividend, scratch);
-      }
-  }
-}
-
-
 void LCodeGen::DoDivI(LDivI* instr) {
   class DeferredDivI: public LDeferredCode {
    public:
@@ -1209,34 +1115,6 @@ void LCodeGen::DoDivI(LDivI* instr) {
 }
 
 
-void LCodeGen::DoMathFloorOfDiv(LMathFloorOfDiv* instr) {
-  const Register result = ToRegister(instr->result());
-  const Register left = ToRegister(instr->InputAt(0));
-  const Register remainder = ToRegister(instr->TempAt(0));
-  const Register scratch = scratch0();
-
-  // We only optimize this for division by constants, because the standard
-  // integer division routine is usually slower than transitionning to VFP.
-  // This could be optimized on processors with SDIV available.
-  ASSERT(instr->InputAt(1)->IsConstantOperand());
-  int32_t divisor = ToInteger32(LConstantOperand::cast(instr->InputAt(1)));
-  if (divisor < 0) {
-    __ cmp(left, Operand(0));
-    DeoptimizeIf(eq, instr->environment());
-  }
-  EmitSignedIntegerDivisionByConstant(result,
-                                      left,
-                                      divisor,
-                                      remainder,
-                                      scratch,
-                                      instr->environment());
-  // We operated a truncating division. Correct the result if necessary.
-  __ cmp(remainder, Operand(0));
-  __ teq(remainder, Operand(divisor), ne);
-  __ sub(result, result, Operand(1), LeaveCC, mi);
-}
-
-
 template<int T>
 void LCodeGen::DoDeferredBinaryOpStub(LTemplateInstruction<1, 2, T>* instr,
                                       Token::Value op) {

src/arm/lithium-codegen-arm.h

@@ -323,17 +323,6 @@ class LCodeGen BASE_EMBEDDED {
                     Register source,
                     int* offset);
 
-  // Emit optimized code for integer division.
-  // Inputs are signed.
-  // All registers are clobbered.
-  // If 'remainder' is no_reg, it is not computed.
-  void EmitSignedIntegerDivisionByConstant(Register result,
-                                           Register dividend,
-                                           int32_t divisor,
-                                           Register remainder,
-                                           Register scratch,
-                                           LEnvironment* environment);
-
   struct JumpTableEntry {
     explicit inline JumpTableEntry(Address entry)
         : label(),

src/arm/macro-assembler-arm.cc

@@ -3710,28 +3710,15 @@ void MacroAssembler::CheckEnumCache(Register null_value, Label* call_runtime) {
 }
 
 
-#ifdef DEBUG
-bool AreAliased(Register reg1,
-                Register reg2,
-                Register reg3,
-                Register reg4,
-                Register reg5,
-                Register reg6) {
-  int n_of_valid_regs = reg1.is_valid() + reg2.is_valid() +
-    reg3.is_valid() + reg4.is_valid() + reg5.is_valid() + reg6.is_valid();
-
-  RegList regs = 0;
-  if (reg1.is_valid()) regs |= reg1.bit();
-  if (reg2.is_valid()) regs |= reg2.bit();
-  if (reg3.is_valid()) regs |= reg3.bit();
-  if (reg4.is_valid()) regs |= reg4.bit();
-  if (reg5.is_valid()) regs |= reg5.bit();
-  if (reg6.is_valid()) regs |= reg6.bit();
-  int n_of_non_aliasing_regs = NumRegs(regs);
-
-  return n_of_valid_regs != n_of_non_aliasing_regs;
+bool AreAliased(Register r1, Register r2, Register r3, Register r4) {
+  if (r1.is(r2)) return true;
+  if (r1.is(r3)) return true;
+  if (r1.is(r4)) return true;
+  if (r2.is(r3)) return true;
+  if (r2.is(r4)) return true;
+  if (r3.is(r4)) return true;
+  return false;
 }
-#endif
 
 
 CodePatcher::CodePatcher(byte* address, int instructions)

src/arm/macro-assembler-arm.h

@@ -85,14 +85,7 @@ enum SmiCheck { INLINE_SMI_CHECK, OMIT_SMI_CHECK };
 enum LinkRegisterStatus { kLRHasNotBeenSaved, kLRHasBeenSaved };
 
 
-#ifdef DEBUG
-bool AreAliased(Register reg1,
-                Register reg2,
-                Register reg3 = no_reg,
-                Register reg4 = no_reg,
-                Register reg5 = no_reg,
-                Register reg6 = no_reg);
-#endif
+bool AreAliased(Register r1, Register r2, Register r3, Register r4);
 
 
 // MacroAssembler implements a collection of frequently used macros.

src/compiler-intrinsics.h

@@ -40,9 +40,6 @@ class CompilerIntrinsics {
   // Returns number of zero bits following most significant 1 bit.
   // Undefined for zero value.
   INLINE(static int CountLeadingZeros(uint32_t value));
-
-  // Returns the number of bits set.
-  INLINE(static int CountSetBits(uint32_t value));
 };
 
 #ifdef __GNUC__
@@ -54,10 +51,6 @@ int CompilerIntrinsics::CountLeadingZeros(uint32_t value) {
   return __builtin_clz(value);
 }
 
-int CompilerIntrinsics::CountSetBits(uint32_t value) {
-  return __builtin_popcount(value);
-}
-
 #elif defined(_MSC_VER)
 
 #pragma intrinsic(_BitScanForward)
@@ -75,10 +68,6 @@ int CompilerIntrinsics::CountLeadingZeros(uint32_t value) {
   return 31 - static_cast<int>(result);
 }
 
-int CompilerIntrinsics::CountSetBits(uint32_t value) {
-  return __popcnt(value);
-}
-
 #else
 #error Unsupported compiler
 #endif

src/frames.cc

@@ -1359,7 +1359,12 @@ InnerPointerToCodeCache::InnerPointerToCodeCacheEntry*
 // -------------------------------------------------------------------------
 
 int NumRegs(RegList reglist) {
-  return CompilerIntrinsics::CountSetBits(reglist);
+  int n = 0;
+  while (reglist != 0) {
+    n++;
+    reglist &= reglist - 1;  // clear one bit
+  }
+  return n;
 }
 
 

src/hydrogen-instructions.cc

@@ -931,62 +931,6 @@ void HJSArrayLength::PrintDataTo(StringStream* stream) {
 }
 
 
-HValue* HUnaryMathOperation::Canonicalize() {
-  if (op() == kMathFloor) {
-    // If the input is integer32 then we replace the floor instruction
-    // with its input. This happens before the representation changes are
-    // introduced.
-    if (value()->representation().IsInteger32()) return value();
-
-#ifdef V8_TARGET_ARCH_ARM
-    if (value()->IsDiv() && (value()->UseCount() == 1)) {
-      // TODO(2038): Implement this optimization for non ARM architectures.
-      HDiv* hdiv = HDiv::cast(value());
-      HValue* left = hdiv->left();
-      HValue* right = hdiv->right();
-      // Try to simplify left and right values of the division.
-      HValue* new_left =
-        LChunkBuilder::SimplifiedDividendForMathFloorOfDiv(left);
-      HValue* new_right =
-        LChunkBuilder::SimplifiedDivisorForMathFloorOfDiv(right);
-
-      // Return if left or right are not optimizable.
-      if ((new_left == NULL) || (new_right == NULL)) return this;
-
-      // Insert the new values in the graph.
-      if (new_left->IsInstruction() &&
-          !HInstruction::cast(new_left)->IsLinked()) {
-        HInstruction::cast(new_left)->InsertBefore(this);
-      }
-      if (new_right->IsInstruction() &&
-          !HInstruction::cast(new_right)->IsLinked()) {
-        HInstruction::cast(new_right)->InsertBefore(this);
-      }
-      HMathFloorOfDiv* instr =  new HMathFloorOfDiv(context(),
-          new_left,
-          new_right);
-      // Replace this HMathFloor instruction by the new HMathFloorOfDiv.
-      instr->InsertBefore(this);
-      ReplaceAllUsesWith(instr);
-      Kill();
-      // We know the division had no other uses than this HMathFloor. Delete it.
-      // Also delete the arguments of the division if they are not used any
-      // more.
-      hdiv->DeleteAndReplaceWith(NULL);
-      ASSERT(left->IsChange() || left->IsConstant());
-      ASSERT(right->IsChange() || right->IsConstant());
-      if (left->HasNoUses())  left->DeleteAndReplaceWith(NULL);
-      if (right->HasNoUses())  right->DeleteAndReplaceWith(NULL);
-
-      // Return NULL to remove this instruction from the graph.
-      return NULL;
-    }
-#endif  // V8_TARGET_ARCH_ARM
-  }
-  return this;
-}
-
-
 HValue* HCheckInstanceType::Canonicalize() {
   if (check_ == IS_STRING &&
       !value()->type().IsUninitialized() &&

src/hydrogen-instructions.h

@@ -140,7 +140,6 @@ class LChunkBuilder;
   V(LoadNamedField)                            \
   V(LoadNamedFieldPolymorphic)                 \
   V(LoadNamedGeneric)                          \
-  V(MathFloorOfDiv)                            \
   V(Mod)                                       \
   V(Mul)                                       \
   V(ObjectLiteral)                             \
@@ -1993,7 +1992,15 @@ class HUnaryMathOperation: public HTemplateInstruction<2> {
     }
   }
 
-  virtual HValue* Canonicalize();
+  virtual HValue* Canonicalize() {
+    // If the input is integer32 then we replace the floor instruction
+    // with its inputs.  This happens before the representation changes are
+    // introduced.
+    if (op() == kMathFloor) {
+      if (value()->representation().IsInteger32()) return value();
+    }
+    return this;
+  }
 
   BuiltinFunctionId op() const { return op_; }
   const char* OpName() const;
@@ -2751,25 +2758,6 @@ class HBitwiseBinaryOperation: public HBinaryOperation {
 };
 
 
-class HMathFloorOfDiv: public HBinaryOperation {
- public:
-  HMathFloorOfDiv(HValue* context, HValue* left, HValue* right)
-      : HBinaryOperation(context, left, right) {
-    set_representation(Representation::Integer32());
-    SetFlag(kUseGVN);
-  }
-
-  virtual Representation RequiredInputRepresentation(int index) {
-    return Representation::Integer32();
-  }
-
-  DECLARE_CONCRETE_INSTRUCTION(MathFloorOfDiv)
-
- protected:
-  virtual bool DataEquals(HValue* other) { return true; }
-};
-
-
 class HArithmeticBinaryOperation: public HBinaryOperation {
  public:
   HArithmeticBinaryOperation(HValue* context, HValue* left, HValue* right)

src/ia32/lithium-ia32.cc

@@ -1355,12 +1355,6 @@ LInstruction* LChunkBuilder::DoDiv(HDiv* instr) {
 }
 
 
-LInstruction* LChunkBuilder::DoMathFloorOfDiv(HMathFloorOfDiv* instr) {
-  UNIMPLEMENTED();
-  return NULL;
-}
-
-
 LInstruction* LChunkBuilder::DoMod(HMod* instr) {
   if (instr->representation().IsInteger32()) {
     ASSERT(instr->left()->representation().IsInteger32());

src/mips/lithium-mips.cc

@@ -1316,12 +1316,6 @@ LInstruction* LChunkBuilder::DoDiv(HDiv* instr) {
 }
 
 
-LInstruction* LChunkBuilder::DoMathFloorOfDiv(HMathFloorOfDiv* instr) {
-  UNIMPLEMENTED();
-  return NULL;
-}
-
-
 LInstruction* LChunkBuilder::DoMod(HMod* instr) {
   if (instr->representation().IsInteger32()) {
     ASSERT(instr->left()->representation().IsInteger32());

src/utils.cc

@@ -89,19 +89,4 @@ char* SimpleStringBuilder::Finalize() {
   return buffer_.start();
 }
 
-
-const DivMagicNumbers DivMagicNumberFor(int32_t divisor) {
-  switch (divisor) {
-    case 3:    return DivMagicNumberFor3;
-    case 5:    return DivMagicNumberFor5;
-    case 7:    return DivMagicNumberFor7;
-    case 9:    return DivMagicNumberFor9;
-    case 11:   return DivMagicNumberFor11;
-    case 25:   return DivMagicNumberFor25;
-    case 125:  return DivMagicNumberFor125;
-    case 625:  return DivMagicNumberFor625;
-    default:   return InvalidDivMagicNumber;
-  }
-}
-
 } }  // namespace v8::internal

src/utils.h

@@ -85,32 +85,6 @@ inline int WhichPowerOf2(uint32_t x) {
 }
 
 
-// Magic numbers for integer division.
-// These are kind of 2's complement reciprocal of the divisors.
-// Details and proofs can be found in:
-// - Hacker's Delight, Henry S. Warren, Jr.
-// - The PowerPC Compiler Writer’s Guide
-// and probably many others.
-// See details in the implementation of the algorithm in
-// lithium-codegen-arm.cc : LCodeGen::TryEmitSignedIntegerDivisionByConstant().
-struct DivMagicNumbers {
-  unsigned M;
-  unsigned s;
-};
-
-const DivMagicNumbers InvalidDivMagicNumber= {0, 0};
-const DivMagicNumbers DivMagicNumberFor3   = {0x55555556, 0};
-const DivMagicNumbers DivMagicNumberFor5   = {0x66666667, 1};
-const DivMagicNumbers DivMagicNumberFor7   = {0x92492493, 2};
-const DivMagicNumbers DivMagicNumberFor9   = {0x38e38e39, 1};
-const DivMagicNumbers DivMagicNumberFor11  = {0x2e8ba2e9, 1};
-const DivMagicNumbers DivMagicNumberFor25  = {0x51eb851f, 3};
-const DivMagicNumbers DivMagicNumberFor125 = {0x10624dd3, 3};
-const DivMagicNumbers DivMagicNumberFor625 = {0x68db8bad, 8};
-
-const DivMagicNumbers DivMagicNumberFor(int32_t divisor);
-
-
 // The C++ standard leaves the semantics of '>>' undefined for
 // negative signed operands. Most implementations do the right thing,
 // though.

src/x64/lithium-x64.cc

@@ -1305,12 +1305,6 @@ LInstruction* LChunkBuilder::DoDiv(HDiv* instr) {
 }
 
 
-LInstruction* LChunkBuilder::DoMathFloorOfDiv(HMathFloorOfDiv* instr) {
-  UNIMPLEMENTED();
-  return NULL;
-}
-
-
 LInstruction* LChunkBuilder::DoMod(HMod* instr) {
   if (instr->representation().IsInteger32()) {
     ASSERT(instr->left()->representation().IsInteger32());