On Wed, 3 Feb 2021 22:48:33 GMT, Gerard Ziemski <gziem...@openjdk.org> wrote:
>> I don't like the idea of using masks on architectures that do not require >> them. How about something like this? >> >> `#if defined(__APPLE__)` >> ` // lldb (gdb) installs both standard BSD signal handlers, and mach >> exception` >> ` // handlers. By replacing the existing task exception handler, we disable >> lldb's mach` >> ` // exception handling, while leaving the standard BSD signal handlers >> functional.` >> ` //` >> ` // EXC_MASK_BAD_ACCESS needed by all architectures for NULL ptr checking` >> ` // EXC_MASK_ARITHMETIC needed by i386` >> ` // EXC_MASK_BAD_INSTRUCTION needed by aarch64 to initiate deoptimization` >> ` kern_return_t kr;` >> ` kr = task_set_exception_ports(mach_task_self(),` >> ` EXC_MASK_BAD_ACCESS` >> ` NOT_LP64(| EXC_MASK_ARITHMETIC)` >> ` AARCH64_ONLY(| EXC_MASK_BAD_INSTRUCTION),` >> ` MACH_PORT_NULL,` >> ` EXCEPTION_STATE_IDENTITY,` >> ` MACHINE_THREAD_STATE);` >> ` ` >> ` assert(kr == KERN_SUCCESS, "could not set mach task signal handler");` >> `#endif` >> >> If I just knew why i386 needs `EXC_MASK_ARITHMETIC` and add that to the >> comment I would be personally happy with that chunk of code. > > No idea how to insert spaces and make text align :-( using ` ```c ` https://docs.github.com/en/github/writing-on-github/creating-and-highlighting-code-blocks I was wrong about `SIGFPE` / `EXC_MASK_ARITHMETIC`, it's used on i386, x86_64: https://github.com/openjdk/jdk/blob/2be60e37e0e433141b2e3d3e32f8e638a4888e3a/src/hotspot/os_cpu/bsd_x86/os_bsd_x86.cpp#L467-L524 and aarch64: https://github.com/AntonKozlov/jdk/blob/80827176cbc5f0dd26003cf234a8076f3f557928/src/hotspot/os_cpu/bsd_aarch64/os_bsd_aarch64.cpp#L309-L323 (What happened with the formatting here, ugh?) Your suggestion sounds good otherwise. @AntonKozlov, do you mind to integrate that? ------------- PR: https://git.openjdk.java.net/jdk/pull/2200
