Hi All, We had sent out an RFC in October on indirect call target profiling. The proposal was about profiling target addresses seen at indirect call sites. Using the profile data we're seeing up to %8 performance improvements on individual spec benchmarks where indirect call sites are present. We've already started uploading our patches to the phabricator. I'm looking forward to your reviews and comments on the code and ready to respond to your design related queries. There were few questions posted on the RFC that were not responded. Here are the much delayed comments. 1) Added dependencies: Our implementation adds dependency on calloc/free as were generating/maintaining a linked list at run time. We also added dependency on the usage of mutexes to prevent memory leaks in the case multiple threads trying to insert a new target address for the same IC site into the linked list. To least impact the performance we only added mutexes around the pointer assignment and kept any dynamic memory allocation/free operations outside of the mutexed code. 2) Indirect call data being present in sampling profile output: This is unfortunately not helping in our case due to perf depending on lbr support. To our knowledge lbr support is not present on ARM platforms. 3) Losing profiling support on targets not supporting malloc/mutexes: The added dependency on calloc/free/mutexes may perhaps be eliminated (although our current solution does not handle this) through having a separate run time library for value profiling purposes. Instrumentation can link in two run time libraries when value profiling (an instance of it being indirect call target profiling) is enabled on the command line. 4) Performance of the instrumented code: Instrumentation with IC profiling patches resulted in 7% degradation across spec benchmarks at -O2. For the benchmarks that did not have any IC sites, no performance degradation was observed. This data is gathered using the ref data set for spec. Thanks, -Betul Buyukkurt Qualcomm Innovation Center, Inc. Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project