diff options
| -rw-r--r-- | lldb/examples/darwin/heap_find/heap_find.cpp | 35 |
1 files changed, 34 insertions, 1 deletions
diff --git a/lldb/examples/darwin/heap_find/heap_find.cpp b/lldb/examples/darwin/heap_find/heap_find.cpp index 48fe83e38e3..15d8c77f52d 100644 --- a/lldb/examples/darwin/heap_find/heap_find.cpp +++ b/lldb/examples/darwin/heap_find/heap_find.cpp @@ -27,8 +27,41 @@ // // (lldb) expression find_cstring_in_heap ("hello") // -// The results will be printed to the STDOUT of the inferior program. +// The results will be printed to the STDOUT of the inferior program. The +// return value of the "find_pointer_in_heap" function is the number of +// pointer references that were found. A quick example shows // +// (lldb) expr find_pointer_in_heap(0x0000000104000410) +// (uint32_t) $5 = 0x00000002 +// 0x104000740: 0x0000000104000410 found in malloc block 0x104000730 + 16 (malloc_size = 48) +// 0x100820060: 0x0000000104000410 found in malloc block 0x100820000 + 96 (malloc_size = 4096) +// +// From the above output we see that 0x104000410 was found in the malloc block +// at 0x104000730 and 0x100820000. If we want to see what these blocks are, we +// can display the memory for this block using the "address" ("A" for short) +// format. The address format shows pointers, and if those pointers point to +// objects that have symbols or know data contents, it will display information +// about the pointers: +/ +// (lldb) memory read --format address --count 1 0x104000730 +// 0x104000730: 0x0000000100002460 (void *)0x0000000100002488: MyString +// +// We can see that the first block is a "MyString" object that contains our +// pointer value at offset 16. +// +// Looking at the next pointers, are a bit more tricky: +// (lldb) memory read -fA 0x100820000 -c1 +// 0x100820000: 0x4f545541a1a1a1a1 +// (lldb) memory read 0x100820000 +// 0x100820000: a1 a1 a1 a1 41 55 54 4f 52 45 4c 45 41 53 45 21 ....AUTORELEASE! +// 0x100820010: 78 00 82 00 01 00 00 00 60 f9 e8 75 ff 7f 00 00 x.......`..u.... +// +// This is an objective C auto release pool object that contains our pointer. +// C++ classes will show up if they are virtual as something like: +// (lldb) memory read --format address --count 1 0x104008000 +// 0x104008000: 0x109008000 vtable for lldb_private::Process +// +// This is a clue that the 0x104008000 is a "lldb_private::Process *". //===----------------------------------------------------------------------===// #include <assert.h> |
