Hi, On Fri, Mar 26 2021, Erick Ochoa via Gcc wrote: > I already have some experience developing SIMPLE_IPA_PASSes, but I am > looking to understand IPA_PASSes better. I have made a hello world ipa > pass that stores "hello world $FUNCTION_NAME" in the function > summaries; however, I am having trouble reading this information back. > Can someone help me understand how to use these interfaces correctly? > > At the moment, it **seems** to be writing information correctly. > (I.e., it doesn't segfault when attempting to write data.) However, in > my read summary function (ipa_hello_world_read_summary (void)) the > function `lto_get_summary_section_data (file_data, > LTO_section_ipa_hello_world, &len);` always returns NULL and > `file_data_vec` is of size 1. This means that at run time, there is > only one call to `lto_get_summary_section_data` and it returns NULL.
I looked at the code you posted and compared it with streaming in ipa-sra.c and did not spot any difference that could result in this behavior. I guess you have checked that the functions are called from proper hooks? (I.e. from write_summary and read_summary or write_optimization_summary and read_optimization_summary, depending on what you are trying to do, and not some mixture of these combinations?) You can try and send the whole patch (hopefully a hello world pass would not be too large) and I can have a look. Martin
