[PATCH] Support for DWARF5 location lists entries

Achra, Nitika
2019-12-31T09:41:15Z

* Handle DW_LLE_base_addressx, DW_LLE_startx_length and DW_LLE_start_length.

Tested by running the testsuite before and after the patch and there is no increase in the number of test cases that fails.

Tested with both -gdwarf-4 and -gdwarf-5 flags.

gdb/ChangeLog:
*gdb/dwarf2loc.c (decode_debug_loclists_addresses): Handle DW_LLE_base_addressx, DW_LLE_startx_length, DW_LLE_start_length.

diff --git a/gdb/dwarf2loc.c b/gdb/dwarf2loc.c
index 976d453d3c..0de956ab66 100644
--- a/gdb/dwarf2loc.c
+++ b/gdb/dwarf2loc.c
@@ -173,6 +173,41 @@ decode_debug_loclists_addresses (struct dwarf2_per_cu_data *per_cu,
switch (*loc_ptr++)
{
+ case DW_LLE_base_addressx:
+ *low = 0;
+ loc_ptr = gdb_read_uleb128(loc_ptr, buf_end, &u64);
+ if (loc_ptr == NULL)
+ return DEBUG_LOC_BUFFER_OVERFLOW;
+ *high = dwarf2_read_addr_index(per_cu, u64);
+ *new_ptr = loc_ptr;
+ return DEBUG_LOC_BASE_ADDRESS;
+ case DW_LLE_startx_length:
+ loc_ptr = gdb_read_uleb128(loc_ptr, buf_end, &u64);
+ if (loc_ptr == NULL)
+ return DEBUG_LOC_BUFFER_OVERFLOW;
+ *low = dwarf2_read_addr_index(per_cu, u64);
+ *high = *low;
+ loc_ptr = gdb_read_uleb128(loc_ptr, buf_end, &u64);
+ if (loc_ptr == NULL)
+ return DEBUG_LOC_BUFFER_OVERFLOW;
+ *high += u64;
+ *new_ptr = loc_ptr;
+ return DEBUG_LOC_START_LENGTH;
+ case DW_LLE_start_length:
+ if (buf_end - loc_ptr < addr_size)
+ return DEBUG_LOC_BUFFER_OVERFLOW;
+ if (signed_addr_p)
+ *low = extract_signed_integer(loc_ptr, addr_size, byte_order);
+ else
+ *low = extract_unsigned_integer(loc_ptr, addr_size, byte_order);
+ loc_ptr += addr_size;
+ *high = *low;
+ loc_ptr = gdb_read_uleb128(loc_ptr, buf_end, &u64);
+ if (loc_ptr == NULL)
+ return DEBUG_LOC_BUFFER_OVERFLOW;
+ *high += u64;
+ *new_ptr = loc_ptr;
+ return DEBUG_LOC_START_LENGTH;
case DW_LLE_end_of_list:
*new_ptr = loc_ptr;
return DEBUG_LOC_END_OF_LIST;
@@ -197,6 +232,9 @@ decode_debug_loclists_addresses (struct dwarf2_per_cu_data *per_cu,