1 files changed, 130 insertions, 0 deletions
diff --git a/gold/stringpool.cc b/gold/stringpool.cc
new file mode 100644
index 0000000..0368014
--- /dev/null
+++ b/gold/stringpool.cc
@@ -0,0 +1,130 @@
+// stringpool.cc -- a string pool for gold
+
+#include "gold.h"
+
+#include <cassert>
+#include <cstring>
+
+#include "stringpool.h"
+
+namespace gold
+{
+
+Stringpool::Stringpool()
+  : string_set_(), strings_()
+{
+}
+
+Stringpool::~Stringpool()
+{
+  for (std::list<stringdata*>::iterator p = this->strings_.begin();
+       p != this->strings_.end();
+       ++p)
+    delete[] reinterpret_cast<char*>(*p);
+}
+
+// Hash function.
+
+size_t
+Stringpool::Stringpool_hash::operator()(const char* s) const
+{
+  // Fowler/Noll/Vo (FNV) hash (type FNV-1a).
+  if (sizeof(size_t) == 8)
+    {
+      size_t result = 14695981039346656037ULL;
+      while (*s != '\0')
+	{
+	  result &= (size_t) *s++;
+	  result *= 1099511628211ULL;
+	}
+      return result;
+    }
+  else
+    {
+      size_t result = 2166136261UL;
+      while (*s != '\0')
+	{
+	  result ^= (size_t) *s++;
+	  result *= 16777619UL;
+	}
+      return result;
+    }
+}
+
+// Add a string to the list of canonical strings.  Return a pointer to
+// the canonical string.
+
+const char*
+Stringpool::add_string(const char* s)
+{
+  const size_t buffer_size = 1000;
+  size_t len = strlen(s);
+
+  size_t alc;
+  bool front = true;
+  if (len >= buffer_size)
+    {
+      alc = sizeof(stringdata) + len;
+      front = false;
+    }
+  else if (this->strings_.empty())
+    alc = sizeof(stringdata) + buffer_size;
+  else
+    {
+      stringdata *psd = this->strings_.front();
+      if (len >= psd->alc - psd->len)
+	alc = sizeof(stringdata) + buffer_size;
+      else
+	{
+	  char* ret = psd->data + psd->len;
+	  memcpy(ret, s, len + 1);
+	  psd->len += len + 1;
+	  return ret;
+	}
+    }
+
+  stringdata *psd = reinterpret_cast<stringdata*>(new char[alc]);
+  psd->alc = alc;
+  memcpy(psd->data, s, len + 1);
+  psd->len = len + 1;
+  if (front)
+    this->strings_.push_front(psd);
+  else
+    this->strings_.push_back(psd);
+  return psd->data;
+}
+
+// Add a string to a string pool.
+
+const char*
+Stringpool::add(const char* s)
+{
+  // FIXME: This will look up the entry twice in the hash table.  The
+  // problem is that we can't insert S before we canonicalize it.  I
+  // don't think there is a way to handle this correct with
+  // unordered_set, so this should be replaced with custom code to do
+  // what we need, which is to return the empty slot.
+
+  String_set_type::const_iterator p = this->string_set_.find(s);
+  if (p != this->string_set_.end())
+    return *p;
+
+  const char* ret = this->add_string(s);
+  std::pair<String_set_type::iterator, bool> ins =
+    this->string_set_.insert(ret);
+  assert(ins.second);
+  return ret;
+}
+
+// Add a prefix of a string to a string pool.
+
+const char*
+Stringpool::add(const char* s, size_t len)
+{
+  // FIXME: This implementation should be rewritten when we rewrite
+  // the hash table to avoid copying.
+  std::string st(s, len);
+  return this->add(st);
+}
+
+} // End namespace gold.