From c3fb11c2c98a5c28ece6a27093a0f9def350ac64 Mon Sep 17 00:00:00 2001 From: Vas Crabb Date: Sat, 7 Jul 2018 02:40:29 +1000 Subject: devcb3 There are multiple issues with the current device callbacks: * They always dispatch through a pointer-to-member * Chained callbacks are a linked list so the branch unit can't predict the early * There's a runtime decision made on the left/right shift direction * There are runtime NULL checks on various objects * Binding a lambda isn't practical * Arbitrary transformations are not supported * When chaining callbacks it isn't clear what the MCFG_DEVCB_ modifiers apply to * It isn't possible to just append to a callback in derived configuration * The macros need a magic, hidden local called devcb * Moving code that uses the magic locals around is error-prone * Writing the MCFG_ macros to make a device usable is a pain * You can't discover applicable MCFG_ macros with intellisense * Macros are not scoped * Using an inappropriate macro isn't detected at compile time * Lots of other things This changeset overcomes the biggest obstacle to remving MCFG_ macros altogether. Essentially, to allow a devcb to be configured, call .bind() and expose the result (a bind target for the callback). Bind target methods starting with "set" repace the current callbacks; methods starting with "append" append to them. You can't reconfigure a callback after resolving it. There's no need to use a macro matching the handler signatures - use FUNC for everything. Current device is implied if no tag/finder is supplied (no need for explicit this). Lambdas are supported, and the memory space and offset are optional. These kinds of things work: * .read_cb().set([this] () { return something; }); * .read_cb().set([this] (offs_t offset) { return ~offset; }); * .write_cb().set([this] (offs_t offset, u8 data) { m_array[offset] = data; }); * .write_cb().set([this] (int state) { some_var = state; }); Arbitrary transforms are allowed, and they can modify offset/mask for example: * .read_cb().set(FUNC(my_state::handler)).transform([] (u8 data) { return bitswap<4>(data, 1, 3, 0, 2); }); * .read_cb().set(m_dev, FUNC(some_device::member)).transform([] (offs_t &offset, u8 data) { offset ^= 3; return data; }); It's possible to stack arbitrary transforms, at the cost of compile time (the whole transform stack gets inlined at compile time). Shifts count as an arbitrary transform, but mask/exor does not. Order of mask/shift/exor now matters. Modifications are applied in the specified order. These are NOT EQUIVALENT: * .read_cb().set(FUNC(my_state::handler)).mask(0x06).lshift(2); * .read_cb().set(FUNC(my_state::handler)).lshift(2).mask(0x06); The bit helper no longer reverses its behaviour for read callbacks, and I/O ports are no longer aware of the field mask. Binding a read callback to no-op is not supported - specify a constant. The GND and VCC aliases have been removed intentionally - they're TTL-centric, and were already being abused. Other quirks have been preserved, including write logger only logging when the data is non-zero (quite unhelpful in many of the cases where it's used). Legacy syntax is still supported for simple cases, but will be phased out. New devices should not have MCFG_ macros. I don't think I've missed any fundamental issues, but if I've broken something, let me know. --- src/devices/sound/ym2151.h | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'src/devices/sound/ym2151.h') diff --git a/src/devices/sound/ym2151.h b/src/devices/sound/ym2151.h index 0aba974025f..a25a424017b 100644 --- a/src/devices/sound/ym2151.h +++ b/src/devices/sound/ym2151.h @@ -41,9 +41,9 @@ //************************************************************************** #define MCFG_YM2151_IRQ_HANDLER(_devcb) \ - devcb = &downcast(*device).set_irq_handler(DEVCB_##_devcb); + downcast(*device).set_irq_handler(DEVCB_##_devcb); #define MCFG_YM2151_PORT_WRITE_HANDLER(_devcb) \ - devcb = &downcast(*device).set_port_write_handler(DEVCB_##_devcb); + downcast(*device).set_port_write_handler(DEVCB_##_devcb); //************************************************************************** @@ -63,6 +63,8 @@ public: // configuration helpers template devcb_base &set_irq_handler(Object &&cb) { return m_irqhandler.set_callback(std::forward(cb)); } template devcb_base &set_port_write_handler(Object &&cb) { return m_portwritehandler.set_callback(std::forward(cb)); } + auto irq_handler() { return m_irqhandler.bind(); } + auto port_write_handler() { return m_portwritehandler.bind(); } // read/write DECLARE_READ8_MEMBER(read); -- cgit v1.2.3 s='content'>
Commit message (Expand)AuthorAgeFilesLines
* Start cleaning up palette configuration: Vas Crabb2018-12-291-1/+1
* src/mame/video: switched various devices to devcb3 and removed MCFG macros (nw) Ivan Vangelista2018-11-211-2/+2
* -nvram: Removed MCFG, nw mooglyguy2018-08-241-2/+2
* ds1315, ds1386, ds2404, ds75160a, ds75161a, eeprom, eepromser, eeprompar: Rem... mooglyguy2018-08-231-1/+1
* more private: use (K,L,M) (#3714) David Haywood2018-06-301-2/+1
* Remove emupal.h from emu.h (nw) AJR2018-06-131-0/+1
* Removed nearly all custom MCFG macros from eepromser, migrated more of police... mooglyguy2018-06-071-1/+1
* as if millions of this pointers suddenly cried out in terror, and were sudden... Vas Crabb2018-06-081-8/+8
* Removed DRIVER_INIT-related macros, made driver init entry in GAME/COMP/CONS ... MooglyGuy2018-05-131-20/+20
* dsp16: fix condition mask in disassembler (nw) Vas Crabb2018-05-091-1/+2
* Streamline machine configuration macros - everyone's a device edition. Vas Crabb2018-05-061-5/+5
* Restrict ROM labels to a filesystem- and shell-safe subset of printable Vas Crabb2018-03-181-16/+18
* Address maps macros removal, pass 1 [O. Galibert] Olivier Galibert2018-03-141-17/+18
* API change: Memory maps are now methods of the owner class [O. Galibert] Olivier Galibert2018-02-121-1/+2