Reorganize code for range analysis and suppress unnecessary debug printing of...

src/hydrogen-instructions.cc

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 102 matching lines @@
 
 void Range::AddConstant(int32_t value) {
   if (value == 0) return;
   bool may_overflow = false;  // Overflow is ignored here.
   lower_ = AddWithoutOverflow(lower_, value, &may_overflow);
   upper_ = AddWithoutOverflow(upper_, value, &may_overflow);
   Verify();
 }
 
 
+void Range::Intersect(Range* other) {
+  upper_ = Min(upper_, other->upper_);
+  lower_ = Max(lower_, other->lower_);
+  bool b = CanBeMinusZero() && other->CanBeMinusZero();
+  set_can_be_minus_zero(b);
+}
+
+
+void Range::Union(Range* other) {
+  upper_ = Max(upper_, other->upper_);
+  lower_ = Min(lower_, other->lower_);
+  bool b = CanBeMinusZero() || other->CanBeMinusZero();
+  set_can_be_minus_zero(b);
+}
+
+
+void Range::Sar(int32_t value) {
+  int32_t bits = value & 0x1F;
+  lower_ = lower_ >> bits;
+  upper_ = upper_ >> bits;
+  set_can_be_minus_zero(false);
+}
+
+
+void Range::Shl(int32_t value) {
+  int32_t bits = value & 0x1F;
+  int old_lower = lower_;
+  int old_upper = upper_;
+  lower_ = lower_ << bits;
+  upper_ = upper_ << bits;
+  if (old_lower != lower_ >> bits || old_upper != upper_ >> bits) {
+    upper_ = kMaxInt;
+    lower_ = kMinInt;
+  }
+  set_can_be_minus_zero(false);
+}
+
+
 bool Range::AddAndCheckOverflow(Range* other) {
   bool may_overflow = false;
   lower_ = AddWithoutOverflow(lower_, other->lower(), &may_overflow);
   upper_ = AddWithoutOverflow(upper_, other->upper(), &may_overflow);
   KeepOrder();
   Verify();
   return may_overflow;
 }
 
 
@@ skipping 275 matching lines @@
   ASSERT(HasRange());
 }
 
 
 void HInstruction::PrintTo(StringStream* stream) {
   stream->Add("%s", Mnemonic());
   if (HasSideEffects()) stream->Add("*");
   stream->Add(" ");
   PrintDataTo(stream);
 
-  if (range() != NULL) {
+  if (range() != NULL &&
+      !range()->IsMostGeneric() &&
+      !range()->CanBeMinusZero()) {
     stream->Add(" range[%d,%d,m0=%d]",
                 range()->lower(),
                 range()->upper(),
                 static_cast<int>(range()->CanBeMinusZero()));
   }
 
   int changes_flags = (flags() & HValue::ChangesFlagsMask());
   if (changes_flags != 0) {
     stream->Add(" changes[0x%x]", changes_flags);
   }
@@ skipping 303 matching lines @@
 Range* HValue::InferRange() {
   if (representation().IsTagged()) {
     // Tagged values are always in int32 range when converted to integer,
     // but they can contain -0.
     Range* result = new Range();
     result->set_can_be_minus_zero(true);
     return result;
   } else if (representation().IsNone()) {
     return NULL;
   } else {
+    // Untagged integer32 cannot be -0 and we don't compute ranges for
+    // untagged doubles.
     return new Range();
   }
 }
 
 
 Range* HConstant::InferRange() {
   if (has_int32_value_) {
     Range* result = new Range(int32_value_, int32_value_);
     result->set_can_be_minus_zero(false);
     return result;
   }
-  return HInstruction::InferRange();
+  return HValue::InferRange();
 }
 
 
 Range* HPhi::InferRange() {
   if (representation().IsInteger32()) {
     if (block()->IsLoopHeader()) {
       Range* range = new Range(kMinInt, kMaxInt);
       return range;
     } else {
       Range* range = OperandAt(0)->range()->Copy();
@@ skipping 13 matching lines @@
     Range* a = left()->range();
     Range* b = right()->range();
     Range* res = a->Copy();
     if (!res->AddAndCheckOverflow(b)) {
       ClearFlag(kCanOverflow);
     }
     bool m0 = a->CanBeMinusZero() && b->CanBeMinusZero();
     res->set_can_be_minus_zero(m0);
     return res;
   } else {
-    return HArithmeticBinaryOperation::InferRange();
+    return HValue::InferRange();
   }
 }
 
 
 Range* HSub::InferRange() {
   if (representation().IsInteger32()) {
     Range* a = left()->range();
     Range* b = right()->range();
     Range* res = a->Copy();
     if (!res->SubAndCheckOverflow(b)) {
       ClearFlag(kCanOverflow);
     }
     res->set_can_be_minus_zero(a->CanBeMinusZero() && b->CanBeZero());
     return res;
   } else {
-    return HArithmeticBinaryOperation::InferRange();
+    return HValue::InferRange();
   }
 }
 
 
 Range* HMul::InferRange() {
   if (representation().IsInteger32()) {
     Range* a = left()->range();
     Range* b = right()->range();
     Range* res = a->Copy();
     if (!res->MulAndCheckOverflow(b)) {
       ClearFlag(kCanOverflow);
     }
     bool m0 = (a->CanBeZero() && b->CanBeNegative()) ||
         (a->CanBeNegative() && b->CanBeZero());
     res->set_can_be_minus_zero(m0);
     return res;
   } else {
-    return HArithmeticBinaryOperation::InferRange();
+    return HValue::InferRange();
   }
 }
 
 
 Range* HDiv::InferRange() {
   if (representation().IsInteger32()) {
     Range* result = new Range();
     if (left()->range()->CanBeMinusZero()) {
       result->set_can_be_minus_zero(true);
     }
 
     if (left()->range()->CanBeZero() && right()->range()->CanBeNegative()) {
       result->set_can_be_minus_zero(true);
     }
 
     if (right()->range()->Includes(-1) && left()->range()->Includes(kMinInt)) {
       SetFlag(HValue::kCanOverflow);
     }
 
     if (!right()->range()->CanBeZero()) {
       ClearFlag(HValue::kCanBeDivByZero);
     }
     return result;
   } else {
-    return HArithmeticBinaryOperation::InferRange();
+    return HValue::InferRange();
   }
 }
 
 
 Range* HMod::InferRange() {
   if (representation().IsInteger32()) {
     Range* a = left()->range();
     Range* result = new Range();
     if (a->CanBeMinusZero() || a->CanBeNegative()) {
       result->set_can_be_minus_zero(true);
     }
     if (!right()->range()->CanBeZero()) {
       ClearFlag(HValue::kCanBeDivByZero);
     }
     return result;
   } else {
-    return HArithmeticBinaryOperation::InferRange();
+    return HValue::InferRange();
   }
 }
 
 
 void HPhi::PrintTo(StringStream* stream) {
   stream->Add("[");
   for (int i = 0; i < OperandCount(); ++i) {
     HValue* value = OperandAt(i);
     stream->Add(" ");
     value->PrintNameTo(stream);
@@ skipping 140 matching lines @@
 void HBinaryOperation::PrintDataTo(StringStream* stream) {
   left()->PrintNameTo(stream);
   stream->Add(" ");
   right()->PrintNameTo(stream);
   if (CheckFlag(kCanOverflow)) stream->Add(" !");
   if (CheckFlag(kBailoutOnMinusZero)) stream->Add(" -0?");
 }
 
 
 Range* HBitAnd::InferRange() {
-  Range* a = left()->range();
-  Range* b = right()->range();
-  int32_t a_mask = 0xffffffff;
-  int32_t b_mask = 0xffffffff;
-  if (a != NULL) a_mask = a->Mask();
-  if (b != NULL) b_mask = b->Mask();
-  int32_t result_mask = a_mask & b_mask;
-  if (result_mask >= 0) {
-    return new Range(0, result_mask);
-  } else {
-    return HBinaryOperation::InferRange();
-  }
+  int32_t left_mask = (left()->range() != NULL)
+      ? left()->range()->Mask()
+      : 0xffffffff;
+  int32_t right_mask = (right()->range() != NULL)
+      ? right()->range()->Mask()
+      : 0xffffffff;
+  int32_t result_mask = left_mask & right_mask;
+  return (result_mask >= 0)
+      ? new Range(0, result_mask)
+      : HValue::InferRange();
 }
 
 
 Range* HBitOr::InferRange() {
-  Range* a = left()->range();
-  Range* b = right()->range();
-  int32_t a_mask = 0xffffffff;
-  int32_t b_mask = 0xffffffff;
-  if (a != NULL) a_mask = a->Mask();
-  if (b != NULL) b_mask = b->Mask();
-  int32_t result_mask = a_mask | b_mask;
-  if (result_mask >= 0) {
-    return new Range(0, result_mask);
-  } else {
-    return HBinaryOperation::InferRange();
-  }
+  int32_t left_mask = (left()->range() != NULL)
+      ? left()->range()->Mask()
+      : 0xffffffff;
+  int32_t right_mask = (right()->range() != NULL)
+      ? right()->range()->Mask()
+      : 0xffffffff;
+  int32_t result_mask = left_mask | right_mask;
+  return (result_mask >= 0)
+      ? new Range(0, result_mask)
+      : HValue::InferRange();
 }
 
 
 Range* HSar::InferRange() {
   if (right()->IsConstant()) {
     HConstant* c = HConstant::cast(right());
     if (c->HasInteger32Value()) {
-      int32_t val = c->Integer32Value();
-      Range* result = NULL;
-      Range* left_range = left()->range();
-      if (left_range == NULL) {
-        result = new Range();
-      } else {
-        result = left_range->Copy();
-      }
-      result->Sar(val);
+      Range* result = (left()->range() != NULL)
+          ? left()->range()->Copy()
+          : new Range();
+      result->Sar(c->Integer32Value());
       return result;
     }
   }
-
-  return HBinaryOperation::InferRange();
+  return HValue::InferRange();
 }
 
 
 Range* HShl::InferRange() {
   if (right()->IsConstant()) {
     HConstant* c = HConstant::cast(right());
     if (c->HasInteger32Value()) {
-      int32_t val = c->Integer32Value();
-      Range* result = NULL;
-      Range* left_range = left()->range();
-      if (left_range == NULL) {
-        result = new Range();
-      } else {
-        result = left_range->Copy();
-      }
-      result->Shl(val);
+      Range* result = (left()->range() != NULL)
+          ? left()->range()->Copy()
+          : new Range();
+      result->Shl(c->Integer32Value());
       return result;
     }
   }
-
-  return HBinaryOperation::InferRange();
+  return HValue::InferRange();
 }
 
 
 
 void HCompare::PrintDataTo(StringStream* stream) {
   stream->Add(Token::Name(token()));
   stream->Add(" ");
   HBinaryOperation::PrintDataTo(stream);
 }
 
@@ skipping 372 matching lines @@
 
 
 void HCheckPrototypeMaps::Verify() {
   HInstruction::Verify();
   ASSERT(HasNoUses());
 }
 
 #endif
 
 } }  // namespace v8::internal