v8::internal::HAliasAnalyzer Class Reference

#include <hydrogen-alias-analysis.h>

Inheritance diagram for v8::internal::HAliasAnalyzer:

Collaboration diagram for v8::internal::HAliasAnalyzer:

Public Member Functions
HAliasing	Query (HValue *a, HValue *b)
bool	MayAlias (HValue *a, HValue *b)
bool	MustAlias (HValue *a, HValue *b)
bool	NoAlias (HValue *a, HValue *b)
Public Member Functions inherited from v8::internal::ZoneObject
	INLINE (void *operator new(size_t size, Zone *zone))
void	operator delete (void *, size_t)
void	operator delete (void *pointer, Zone *zone)

Detailed Description

Definition at line 23 of file hydrogen-alias-analysis.h.

Member Function Documentation

MayAlias()

bool v8::internal::HAliasAnalyzer::MayAlias ( HValue *  a, HValue *  b  )

inline

Definition at line 57 of file hydrogen-alias-analysis.h.

                                             {
    return Query(a, b) != kNoAlias;
  }

References v8::internal::kNoAlias, and Query().

Referenced by v8::internal::HCheckTable::Kill(), v8::internal::HLoadEliminationTable::KillFieldInternal(), and v8::internal::HStoreEliminationPhase::ProcessLoad().

Here is the call graph for this function:

Here is the caller graph for this function:

MustAlias()

bool v8::internal::HAliasAnalyzer::MustAlias ( HValue *  a, HValue *  b  )

inline

Definition at line 61 of file hydrogen-alias-analysis.h.

                                              {
    return Query(a, b) == kMustAlias;
  }

References v8::internal::kMustAlias, and Query().

Referenced by v8::internal::HCheckTable::Find(), v8::internal::HLoadEliminationTable::Find(), v8::internal::HLoadEliminationTable::FindOrCreate(), and v8::internal::HStoreEliminationPhase::ProcessStore().

Here is the call graph for this function:

Here is the caller graph for this function:

NoAlias()

bool v8::internal::HAliasAnalyzer::NoAlias ( HValue *  a, HValue *  b  )

inline

Definition at line 65 of file hydrogen-alias-analysis.h.

                                            {
    return Query(a, b) == kNoAlias;
  }

References v8::internal::kNoAlias, and Query().

Here is the call graph for this function:

Query()

HAliasing v8::internal::HAliasAnalyzer::Query ( HValue *  a, HValue *  b  )

inline

Definition at line 27 of file hydrogen-alias-analysis.h.

                                        {
    // The same SSA value always references the same object.
    if (a == b) return kMustAlias;
 
    if (a->IsAllocate() || a->IsInnerAllocatedObject()) {
      // Two non-identical allocations can never be aliases.
      if (b->IsAllocate()) return kNoAlias;
      if (b->IsInnerAllocatedObject()) return kNoAlias;
      // An allocation can never alias a parameter or a constant.
      if (b->IsParameter()) return kNoAlias;
      if (b->IsConstant()) return kNoAlias;
    }
    if (b->IsAllocate() || b->IsInnerAllocatedObject()) {
      // An allocation can never alias a parameter or a constant.
      if (a->IsParameter()) return kNoAlias;
      if (a->IsConstant()) return kNoAlias;
    }
 
    // Constant objects can be distinguished statically.
    if (a->IsConstant()) {
      // TODO(titzer): DataEquals() is more efficient, but that's protected.
      return a->Equals(b) ? kMustAlias : kNoAlias;
    }
    return kMayAlias;
  }

References v8::internal::HValue::Equals(), v8::internal::kMayAlias, v8::internal::kMustAlias, and v8::internal::kNoAlias.

Referenced by MayAlias(), MustAlias(), and NoAlias().

Here is the call graph for this function:

Here is the caller graph for this function:

---

The documentation for this class was generated from the following file:

• /mnt/V8SourceCode/src/hydrogen-alias-analysis.h