#include "gold.h"
-#include <cassert>
#include <cstring>
+#include <algorithm>
+#include <vector>
+#include "output.h"
#include "stringpool.h"
namespace gold
{
Stringpool::Stringpool()
- : string_set_(), strings_()
+ : string_set_(), strings_(), strtab_size_(0), next_index_(1)
{
}
Stringpool::~Stringpool()
{
- for (std::list<stringdata*>::iterator p = this->strings_.begin();
+ for (std::list<Stringdata*>::iterator p = this->strings_.begin();
p != this->strings_.end();
++p)
delete[] reinterpret_cast<char*>(*p);
// Fowler/Noll/Vo (FNV) hash (type FNV-1a).
if (sizeof(size_t) == 8)
{
- size_t result = 14695981039346656037ULL;
+ size_t result = static_cast<size_t>(14695981039346656037ULL);
while (*s != '\0')
{
result &= (size_t) *s++;
}
// Add a string to the list of canonical strings. Return a pointer to
-// the canonical string.
+// the canonical string. If PKEY is not NULL, set *PKEY to the key.
const char*
-Stringpool::add_string(const char* s)
+Stringpool::add_string(const char* s, Key* pkey)
{
+ // We are in trouble if we've already computed the string offsets.
+ gold_assert(this->strtab_size_ == 0);
+
+ // The size we allocate for a new Stringdata.
const size_t buffer_size = 1000;
+ // The amount we multiply the Stringdata index when calculating the
+ // key.
+ const size_t key_mult = 1024;
+ gold_assert(key_mult >= buffer_size);
+
size_t len = strlen(s);
size_t alc;
bool front = true;
if (len >= buffer_size)
{
- alc = sizeof(stringdata) + len;
+ alc = sizeof(Stringdata) + len;
front = false;
}
else if (this->strings_.empty())
- alc = sizeof(stringdata) + buffer_size;
+ alc = sizeof(Stringdata) + buffer_size;
else
{
- stringdata *psd = this->strings_.front();
+ Stringdata *psd = this->strings_.front();
if (len >= psd->alc - psd->len)
- alc = sizeof(stringdata) + buffer_size;
+ alc = sizeof(Stringdata) + buffer_size;
else
{
char* ret = psd->data + psd->len;
memcpy(ret, s, len + 1);
+
+ if (pkey != NULL)
+ *pkey = psd->index * key_mult + psd->len;
+
psd->len += len + 1;
+
return ret;
}
}
- stringdata *psd = reinterpret_cast<stringdata*>(new char[alc]);
- psd->alc = alc;
+ Stringdata *psd = reinterpret_cast<Stringdata*>(new char[alc]);
+ psd->alc = alc - sizeof(Stringdata);
memcpy(psd->data, s, len + 1);
psd->len = len + 1;
+ psd->index = this->next_index_;
+ ++this->next_index_;
+
+ if (pkey != NULL)
+ *pkey = psd->index * key_mult;
+
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)
+Stringpool::add(const char* s, Key* pkey)
{
// 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 correctly with
- // unordered_set, so this should be replaced with custom code to do
+ // unordered_map, 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;
+ {
+ if (pkey != NULL)
+ *pkey = p->second.first;
+ return p->first;
+ }
- const char* ret = this->add_string(s);
+ Key k;
+ const char* ret = this->add_string(s, &k);
+
+ const off_t ozero = 0;
+ std::pair<const char*, Val> element(ret, std::make_pair(k, ozero));
std::pair<String_set_type::iterator, bool> ins =
- this->string_set_.insert(ret);
- assert(ins.second);
+ this->string_set_.insert(element);
+ gold_assert(ins.second);
+
+ if (pkey != NULL)
+ *pkey = k;
+
return ret;
}
// Add a prefix of a string to a string pool.
const char*
-Stringpool::add(const char* s, size_t len)
+Stringpool::add(const char* s, size_t len, Key* pkey)
{
// FIXME: This implementation should be rewritten when we rewrite
// the hash table to avoid copying.
std::string st(s, len);
- return this->add(st);
+ return this->add(st, pkey);
+}
+
+const char*
+Stringpool::find(const char* s, Key* pkey) const
+{
+ String_set_type::const_iterator p = this->string_set_.find(s);
+ if (p == this->string_set_.end())
+ return NULL;
+
+ if (pkey != NULL)
+ *pkey = p->second.first;
+
+ return p->first;
+}
+
+// Comparison routine used when sorting into an ELF strtab. We want
+// to sort this so that when one string is a suffix of another, we
+// always see the shorter string immediately after the longer string.
+// For example, we want to see these strings in this order:
+// abcd
+// cd
+// d
+// When strings are not suffixes, we don't care what order they are
+// in, but we need to ensure that suffixes wind up next to each other.
+// So we do a reversed lexicographic sort on the reversed string.
+
+bool
+Stringpool::Stringpool_sort_comparison::operator()(
+ String_set_type::iterator it1,
+ String_set_type::iterator it2) const
+{
+ const char* s1 = it1->first;
+ const char* s2 = it2->first;
+ int len1 = strlen(s1);
+ int len2 = strlen(s2);
+ int minlen = len1 < len2 ? len1 : len2;
+ const char* p1 = s1 + len1 - 1;
+ const char* p2 = s2 + len2 - 1;
+ for (int i = minlen - 1; i >= 0; --i, --p1, --p2)
+ {
+ if (*p1 != *p2)
+ return *p1 > *p2;
+ }
+ return len1 > len2;
+}
+
+// Return whether s1 is a suffix of s2.
+
+bool
+Stringpool::is_suffix(const char* s1, const char* s2)
+{
+ size_t len1 = strlen(s1);
+ size_t len2 = strlen(s2);
+ if (len1 > len2)
+ return false;
+ return strcmp(s1, s2 + len2 - len1) == 0;
+}
+
+// Turn the stringpool into an ELF strtab: determine the offsets of
+// each string in the table.
+
+void
+Stringpool::set_string_offsets()
+{
+ if (this->strtab_size_ != 0)
+ {
+ // We've already computed the offsets.
+ return;
+ }
+
+ size_t count = this->string_set_.size();
+
+ std::vector<String_set_type::iterator> v;
+ v.reserve(count);
+
+ for (String_set_type::iterator p = this->string_set_.begin();
+ p != this->string_set_.end();
+ ++p)
+ v.push_back(p);
+
+ std::sort(v.begin(), v.end(), Stringpool_sort_comparison());
+
+ // Offset 0 is reserved for the empty string.
+ off_t offset = 1;
+ for (size_t i = 0; i < count; ++i)
+ {
+ if (v[i]->first[0] == '\0')
+ v[i]->second.second = 0;
+ else if (i > 0 && Stringpool::is_suffix(v[i]->first, v[i - 1]->first))
+ v[i]->second.second = (v[i - 1]->second.second
+ + strlen(v[i - 1]->first)
+ - strlen(v[i]->first));
+ else
+ {
+ v[i]->second.second = offset;
+ offset += strlen(v[i]->first) + 1;
+ }
+ }
+
+ this->strtab_size_ = offset;
+}
+
+// Get the offset of a string in the ELF strtab. The string must
+// exist.
+
+off_t
+Stringpool::get_offset(const char* s) const
+{
+ gold_assert(this->strtab_size_ != 0);
+ String_set_type::const_iterator p = this->string_set_.find(s);
+ if (p != this->string_set_.end())
+ return p->second.second;
+ gold_unreachable();
+}
+
+// Write the ELF strtab into the output file at the specified offset.
+
+void
+Stringpool::write(Output_file* of, off_t offset)
+{
+ gold_assert(this->strtab_size_ != 0);
+ unsigned char* viewu = of->get_output_view(offset, this->strtab_size_);
+ char* view = reinterpret_cast<char*>(viewu);
+ view[0] = '\0';
+ for (String_set_type::const_iterator p = this->string_set_.begin();
+ p != this->string_set_.end();
+ ++p)
+ strcpy(view + p->second.second, p->first);
+ of->write_output_view(offset, this->strtab_size_, viewu);
}
} // End namespace gold.
projects / deliverable / binutils-gdb.git / blobdiff