On Wed, May 14, 2014 at 1:18 AM, Ilya Enkovich <enkovich....@gmail.com> wrote: > 2014-05-13 23:21 GMT+04:00 Jeff Law <l...@redhat.com>: >> On 05/13/14 02:38, Ilya Enkovich wrote: >>>>> >>>>> propagate constant bounds value and remove checks in called function). >>>> >>>> >>>> So from a linking standpoint, presumably you have to mangle the >>>> instrumented >>>> caller/callee in some manner. Right? Or are you dynamically dispatching >>>> somehow? >>> >>> >>> Originally the idea was o have instrumented clone to have the same >>> assembler name as the original function. Since instrumented code is >>> fully compatible with not instrumented code, we always emit only one >>> version. Usage of the same assembler name allows instrumented and not >>> instrumented calls to look similar in assembler. It worked fine until >>> I tried it with LTO where assembler name is used as a unique >>> identifier. With linker resolutions files it became even more harder >>> to use such approach. To resolve these issues I started to use new >>> assembler name with postfix, but linked with the original name using >>> IDENTIFIER_TRANSPARENT_ALIAS. It gives different assembler names for >>> clones and originals during compilation, but both clone and original >>> functions have similar name in output assembler. >> >> OK. So if I read that correctly, it implies that the existence of bounds >> information does not change the signature of the callee. This is obviously >> important for C++. >> >> Sounds like I need to sit down with the branch and see how this works in the >> new scheme. > > Both mpx branch and Wiki > (http://gcc.gnu.org/wiki/Intel%20MPX%20support%20in%20the%20GCC%20compiler) > page are up-to-date now and may be tried out either in NOP mode or > with simulator. Let me know if you have any troubles with using it. >
I built it. But "-fcheck-pointer-bounds -mmpx" doesn't generate MPX enabled executable which runs on both MPX-enabled and non MPX-enabled hardwares. I didn't see any MPX run-time library. -- H.J.
