On Wed, 23 Aug 2023 22:40:23 GMT, David Holmes <dhol...@openjdk.org> wrote:
>> This change wasn't in the original patch, but the >> `GENERATE_STATIC_PTR_VOLATILE_VM_STRUCT_ENTRY` change above it was. I found >> it when I noticed the use of `GENERATE_STATIC_PTR_VOLATILE_VM_STRUCT_ENTRY` >> and thought it should be renamed too. I was also doing "static volatile" -> >> "volatile stack" at the time so that is also part of this macros rename. >> >> As David points out, the purpose is to make it more general purpose, >> although for this macro only the name change is needed >> (`GENERATE_STATIC_PTR_VOLATILE_VM_STRUCT_ENTRY also has a minor >> implementation change that was needed). >> >> The comments for both of these macros references "static pointer volatile" >> entries. That should changed to "volatile static". The type no longer needs >> to be a pointer type. >> >> I'm not certain what this CHECK macro does, but it was pre-existing, and >> there is also the `CHECK_STATIC_VM_STRUCT_ENTRY` macro above it which is >> identical except of the absence of "volatile" in the name and >> implementation. I think it verifies that the type specified in the >> vmstructs definition of the field is actually the same as the field itself. >> The macro will generate a compiler error if a cast was needed. I think this >> type of check can only be done with static fields. You would need an >> instance of the class/struct to do a similar check on an instance field. >> Thus CHECK_NONSTATIC_VM_STRUCT_ENTRY is much more complex and seems to be a >> runtime check that will assert if it fails. > > I can't convince myself that `volatile` is in the right place in `type > volatile * dummy`. But `volatile * dummy` means that the pointer is volatile > as opposed to the type being pointed to, which would match with the original > macro name's use of `PTR_VOLATILE`. @dholmes-ora I'm not sure what is needed to move forward with this. Are you OK with the change? ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/15373#discussion_r1306091948
