The first option is a flag that enables MPC601 (POWER) instructions for CPUs that are not MPC601.
This can be useful for the following reasons:
1) To produce results similar to classic Mac OS which emulates MPC601 instructions on CPUs that don't implement MPC601 instructions. This option is used to compare the risu traces produced in Mac OS 9 on a G3 or G4 with DPPC.
2) May increase performance in apps that use POWER instructions on emulated machines with CPUs that are not MPC601. It is not known if any such apps exist but there could be since Apple included MPC601 emulation in classic Mac OS.
scsibus has a new method attach_scsi_devices which is used by all machines to populate a SCSI bus with one or more hard drives or CD-ROM drives.
HDDs are specified by the hdd_img property.
CDs are specified by the cdr_img property.
Multiple images are delimited by a colon :
attach_scsi_devices is called by the scsi controller after the scsi controller has attached itself to the scsi bus.
The bus suffix is applied to the property name.
Curio has no suffix so it will use hdd_img and cdr_img properties.
Mesh is expected to have a suffix of 2 so it will use hdd_img2 and cdr_img2 properties.
HDDs will skip SCSI ID 3 unless 7 HDDs are added, in which case, the seventh HDD will use ID 3.
CDs will start at SCSI ID 3, go to 7, then down to 0.
SCSI IDs are skipped if a device is already using that SCSI ID.
ScsiCdrom and ScsiHD no longer use REGISTER_DEVICE or DeviceDescription or PropMap which is normal for devices that can have multiple instances.
Result of running IWYU (https://include-what-you-use.org/) and
applying most of the suggestions about unncessary includes and
forward declarations.
Was motivated by observing that <thread> was being included in
ppcopcodes.cpp even though it was unused (found while researching
the use of threads), but seems generally good to help with build
times and correctness.