Shared library support for rv-predict.

[virgil-serbanuta]

Sample output for lpcq. Note the extra pipes in the stack addresses.

-- Window 1 --
-- Window 2 --
Data race on [0x000000000177fcf0 : 0x0000000000401ee2/0x00007fcca4d72c80]:
Read in thread 2
> {0x0000000000401f90|}
{0x0000000000402c5e|}
{0x000000000040a0c6|}
Thread 2 created by thread 1
{0x00000000004028fd|}

Write in thread 1
  > {0x0000000000402189|}
    {0x0000000000403078|}
    {0x0000000000402a13|}
    {0x00007fcca62b5830|/lib/x86_64-linux-gnu/libc.so.6}
Thread 1 is the main thread

Data race on [0x00007ffe9c252018 : 0x0000000000402fb5/0x00007ffe9c251e60 0x00000000004024de/0x00007ffe9c252050]:
Read in thread 2
> {0x0000000000401f0d|}
{0x0000000000402c5e|}
{0x000000000040a0c6|}
Thread 2 created by thread 1
{0x00000000004028fd|}

Write in thread 1
  > {0x0000000000402162|}
    {0x0000000000403078|}
    {0x0000000000402a13|}
    {0x00007fcca62b5830|/lib/x86_64-linux-gnu/libc.so.6}
Thread 1 is the main thread

[gnuoyd]

Since get_ub_length() >= oi->oi_reclen, you probably don't need both this and the following code.

[virgil-serbanuta]

I added a code comment with my current understanding of the code, explaining why the two if statements are needed, please tell me if I am wrong.

[virgil-serbanuta]

Hi David,

I'll be travelling in the next two days, and I don't know how much I'll be able to continue this work until Monday, so here are some details in case you need them:

I tried to make the addresses resolvable with addr2line in various ways, but I couldn't. Here's an example with a race, which has a dynamic library with debug symbols in its trace:
#813

As compiled on my computer, the stack trace address lies in the second LOAD section of libsharedlibrary.so, with an offset of 0x677, which puts it in the .text segment, with an offset of 0x117 (values computed from the offsets printed by the progam and by readelf -l libsharedlibrary.so and readelf -S libsharedlibrary.so; since I got an address near the end of the .text segment, I assume that they are correct).

However, addr2line does not seem impressed by my computations, and I can't figure out how to make it print anything related to my code, e.g.:
:virgil@vdtop:~/runtime-verification/tmp/examples/library-example$ addr2line -j .text -e libsharedlibrary.so 117
??:?

I've also tried other ways of making addr2line return an address in my code, but failed.