switch (extended_op)
{
case elfcpp::DW_LNE_end_sequence:
+ // This means that the current byte is the one immediately
+ // after a set of instructions. Record the current line
+ // for up to one less than the current address.
+ lsm->line_num = -1;
lsm->end_sequence = true;
*len = oplen;
return true;
return this->symtab_buffer_ != NULL;
}
+// Given an Offset_to_lineno_entry vector, and an offset, figure out
+// if the offset points into a function according to the vector (see
+// comments below for the algorithm). If it does, return an iterator
+// into the vector that points to the line-number that contains that
+// offset. If not, it returns vector::end().
+
+static std::vector<Offset_to_lineno_entry>::const_iterator
+offset_to_iterator(const std::vector<Offset_to_lineno_entry>* offsets,
+ off_t offset)
+{
+ const Offset_to_lineno_entry lookup_key = { offset, 0, 0, 0 };
+
+ // lower_bound() returns the smallest offset which is >= lookup_key.
+ // If no offset in offsets is >= lookup_key, returns end().
+ std::vector<Offset_to_lineno_entry>::const_iterator it
+ = std::lower_bound(offsets->begin(), offsets->end(), lookup_key);
+
+ // This code is easiest to understand with a concrete example.
+ // Here's a possible offsets array:
+ // {{offset = 3211, header_num = 0, file_num = 1, line_num = 16}, // 0
+ // {offset = 3224, header_num = 0, file_num = 1, line_num = 20}, // 1
+ // {offset = 3226, header_num = 0, file_num = 1, line_num = 22}, // 2
+ // {offset = 3231, header_num = 0, file_num = 1, line_num = 25}, // 3
+ // {offset = 3232, header_num = 0, file_num = 1, line_num = -1}, // 4
+ // {offset = 3232, header_num = 0, file_num = 1, line_num = 65}, // 5
+ // {offset = 3235, header_num = 0, file_num = 1, line_num = 66}, // 6
+ // {offset = 3236, header_num = 0, file_num = 1, line_num = -1}, // 7
+ // {offset = 5764, header_num = 0, file_num = 1, line_num = 47}, // 8
+ // {offset = 5765, header_num = 0, file_num = 1, line_num = 48}, // 9
+ // {offset = 5767, header_num = 0, file_num = 1, line_num = 49}, // 10
+ // {offset = 5768, header_num = 0, file_num = 1, line_num = 50}, // 11
+ // {offset = 5773, header_num = 0, file_num = 1, line_num = -1}, // 12
+ // {offset = 5787, header_num = 1, file_num = 1, line_num = 19}, // 13
+ // {offset = 5790, header_num = 1, file_num = 1, line_num = 20}, // 14
+ // {offset = 5793, header_num = 1, file_num = 1, line_num = 67}, // 15
+ // {offset = 5793, header_num = 1, file_num = 1, line_num = -1}, // 16
+ // {offset = 5795, header_num = 1, file_num = 1, line_num = 68}, // 17
+ // {offset = 5798, header_num = 1, file_num = 1, line_num = -1}, // 18
+ // The entries with line_num == -1 mark the end of a function: the
+ // associated offset is one past the last instruction in the
+ // function. This can correspond to the beginning of the next
+ // function (as is true for offset 3232); alternately, there can be
+ // a gap between the end of one function and the start of the next
+ // (as is true for some others, most obviously from 3236->5764).
+ //
+ // Case 1: lookup_key has offset == 10. lower_bound returns
+ // offsets[0]. Since it's not an exact match and we're
+ // at the beginning of offsets, we return end() (invalid).
+ // Case 2: lookup_key has offset 10000. lower_bound returns
+ // offset[19] (end()). We return end() (invalid).
+ // Case 3: lookup_key has offset == 3211. lower_bound matches
+ // offsets[0] exactly, and that's the entry we return.
+ // Case 4: lookup_key has offset == 3232. lower_bound returns
+ // offsets[4]. That's an exact match, but indicates
+ // end-of-function. We check if offsets[5] is also an
+ // exact match but not end-of-function. It is, so we
+ // return offsets[5].
+ // Case 5: lookup_key has offset == 3214. lower_bound returns
+ // offsets[1]. Since it's not an exact match, we back
+ // up to the offset that's < lookup_key, offsets[0].
+ // We note offsets[0] is a valid entry (not end-of-function),
+ // so that's the entry we return.
+ // Case 6: lookup_key has offset == 4000. lower_bound returns
+ // offsets[8]. Since it's not an exact match, we back
+ // up to offsets[7]. Since offsets[7] indicates
+ // end-of-function, we know lookup_key is between
+ // functions, so we return end() (not a valid offset).
+ // Case 7: lookup_key has offset == 5794. lower_bound returns
+ // offsets[17]. Since it's not an exact match, we back
+ // up to offsets[15]. Note we back up to the *first*
+ // entry with offset 5793, not just offsets[17-1].
+ // We note offsets[15] is a valid entry, so we return it.
+ // If offsets[15] had had line_num == -1, we would have
+ // checked offsets[16]. The reason for this is that
+ // 15 and 16 can be in an arbitrary order, since we sort
+ // only by offset. (Note it doesn't help to use line_number
+ // as a secondary sort key, since sometimes we want the -1
+ // to be first and sometimes we want it to be last.)
+
+ // This deals with cases (1) and (2).
+ if ((it == offsets->begin() && offset < it->offset)
+ || it == offsets->end())
+ return offsets->end();
+
+ // This deals with cases (3) and (4).
+ if (offset == it->offset)
+ {
+ while (it != offsets->end()
+ && it->offset == offset
+ && it->line_num == -1)
+ ++it;
+ if (it == offsets->end() || it->offset != offset)
+ return offsets->end();
+ else
+ return it;
+ }
+
+ // This handles the first part of case (7) -- we back up to the
+ // *first* entry that has the offset that's behind us.
+ gold_assert(it != offsets->begin());
+ std::vector<Offset_to_lineno_entry>::const_iterator range_end = it;
+ --it;
+ const off_t range_value = it->offset;
+ while (it != offsets->begin() && (it-1)->offset == range_value)
+ --it;
+
+ // This handles cases (5), (6), and (7): if any entry in the
+ // equal_range [it, range_end) has a line_num != -1, it's a valid
+ // match. If not, we're not in a function.
+ for (; it != range_end; ++it)
+ if (it->line_num != -1)
+ return it;
+ return offsets->end();
+}
// Return a string for a file name and line number.
if (this->data_valid_ == false)
return "";
- const Offset_to_lineno_entry lookup_key = { offset, 0, 0, 0 };
const std::vector<Offset_to_lineno_entry>* offsets;
// If we do not have reloc information, then our input is a .so or
// some similar data structure where all the information is held in
return "";
typename std::vector<Offset_to_lineno_entry>::const_iterator it
- = std::lower_bound(offsets->begin(), offsets->end(), lookup_key);
-
- // If we found an exact match, great, otherwise find the last entry
- // before the passed-in offset.
- if (it->offset > offset)
- {
- if (it == offsets->begin())
- return "";
- --it;
- gold_assert(it->offset < offset);
- }
+ = offset_to_iterator(offsets, offset);
+ if (it == offsets->end())
+ return "";
// Convert the file_num + line_num into a string.
std::string ret;
// Dwarf_line_info routines.
-// Note: this routine instantiates the appropriate
-// Sized_dwarf_line_info templates for this config, so we don't have
-// to have a separte instantiation section for them.
-
std::string
Dwarf_line_info::one_addr2line(Object* object,
unsigned int shndx, off_t offset)
projects / deliverable / binutils-gdb.git / blobdiff