reloc-info-inl.h

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// Copyright 2023 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
 
#ifndef V8_CODEGEN_RELOC_INFO_INL_H_
#define V8_CODEGEN_RELOC_INFO_INL_H_
 
#include "src/codegen/reloc-info.h"
// Include the non-inl header before the rest of the headers.
 
#include "src/codegen/assembler-inl.h"
#include "src/heap/heap-write-barrier-inl.h"
 
namespace v8 {
namespace internal {
 
template <typename ObjectVisitor>
void RelocInfo::Visit(Tagged<InstructionStream> host, ObjectVisitor* visitor) {
  Mode mode = rmode();
  if (IsEmbeddedObjectMode(mode)) {
    visitor->VisitEmbeddedPointer(host, this);
  } else if (IsCodeTargetMode(mode)) {
    visitor->VisitCodeTarget(host, this);
  } else if (IsExternalReference(mode)) {
    visitor->VisitExternalReference(host, this);
  } else if (IsInternalReference(mode) || IsInternalReferenceEncoded(mode)) {
    visitor->VisitInternalReference(host, this);
  } else if (IsBuiltinEntryMode(mode)) {
    visitor->VisitOffHeapTarget(host, this);
  } else if (IsJSDispatchHandle(mode)) {
#ifdef V8_ENABLE_LEAPTIERING
    // This would need to pass the RelocInfo if dispatch entries were allowed
    // to move and we needed to update this slot.
    static_assert(!JSDispatchTable::kSupportsCompaction);
    visitor->VisitJSDispatchTableEntry(host, js_dispatch_handle());
#else
    UNREACHABLE();
#endif
  }
}
 
void WritableRelocInfo::set_target_object(Tagged<InstructionStream> host,
                                          Tagged<HeapObject> target,
                                          WriteBarrierMode write_barrier_mode,
                                          ICacheFlushMode icache_flush_mode) {
  set_target_object(target, icache_flush_mode);
  if (!v8_flags.disable_write_barriers) {
    WriteBarrier::ForRelocInfo(host, this, target, write_barrier_mode);
  }
}
 
template <typename RelocInfoT>
RelocIteratorBase<RelocInfoT>::RelocIteratorBase(RelocInfoT reloc_info,
                                                 const uint8_t* pos,
                                                 const uint8_t* end,
                                                 int mode_mask)
    : pos_(pos), end_(end), rinfo_(reloc_info), mode_mask_(mode_mask) {
  DCHECK_EQ(reloc_info.rmode(), RelocInfo::NO_INFO);
  DCHECK_EQ(reloc_info.data(), 0);
  // Relocation info is read backwards.
  DCHECK_GE(pos_, end_);
  if (mode_mask_ == 0) pos_ = end_;
  next();
}
 
}  // namespace internal
}  // namespace v8
 
#endif  // V8_CODEGEN_RELOC_INFO_INL_H_