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* emumem: Rename direct_read_handler to memory_access_cache. Parametrize the ↵ Olivier Galibert2018-05-111-1/+183
| | | | template on more information (data width, endianness) to make it possible to turn it into an handler cache eventually, and not just a memory block cache. Make it capable of large and unaligned accesses. [O. Galibert]
* dirom.cpp: add missing license header (nw) hap2018-03-241-0/+3
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* destaticify initializations (nw) (#3289) wilbertpol2018-03-041-9/+0
| | | | | | * destaticify initializations (nw) * fix this->set_screen (nw)
* Revert "Revert "Merge branch 'master' of https://github.com/mamedev/mame"" Firehawke2017-12-131-8/+12
| | | | This reverts commit 54155441e9ba9941e85d80c4834a66376a11e791.
* Revert "Merge branch 'master' of https://github.com/mamedev/mame" Firehawke2017-12-131-12/+8
| | | | | This reverts commit f537428e5a40ba6dde8ca9bf0fe9ae6b1f189ac4, reversing changes made to 0d70d798107d4e4e8fb9f230410aeb1e888d65c5.
* Moderate overhaul of device_rom_interface (nw) AJR2017-12-101-8/+12
| | | | | | | | | - Allow endianness and data/address width to be altered during configuration - Raise memory_space_config from private to protected so it can be overridden - Make entire interface optional (as needed by one device to be added soon) - Use interface_post_load instead of explicitly registered delegate - Only call rom_bank_updated when bank actually changes - Remove prototypes for nonexistent functions
* emumem: API change [O. Galibert] Olivier Galibert2017-11-291-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * direct_read_data is now a template which takes the address bus shift as a parameter. * address_space::direct<shift>() is now a template method that takes the shift as a parameter and returns a pointer instead of a reference * the address to give to {read|write}_* on address_space or direct_read_data is now the address one wants to access Longer explanation: Up until now, the {read|write}_* methods required the caller to give the byte offset instead of the actual address. That's the same on byte-addressing CPUs, e.g. the ones everyone knows, but it's different on the word/long/quad addressing ones (tms, sharc, etc...) or the bit-addressing one (tms340x0). Changing that required templatizing the direct access interface on the bus addressing granularity, historically called address bus shift. Also, since everybody was taking the address of the reference returned by direct(), and structurally didn't have much choice in the matter, it got changed to return a pointer directly. Longest historical explanation: In a cpu core, the hottest memory access, by far, is the opcode fetching. It's also an access with very good locality (doesn't move much, tends to stay in the same rom/ram zone even when jumping around, tends not to hit handlers), which makes efficient caching worthwhile (as in, 30-50% faster core iirc on something like the 6502, but that was 20 years ago and a number of things changed since then). In fact, opcode fetching was, in the distant past, just an array lookup indexed by pc on an offset pointer, which was updated on branches. It didn't stay that way because more elaborate access is often needed (handlers, banking with instructions crossing a bank...) but it still ends up with a frontend of "if the address is still in the current range read from pointer+address otherwise do the slowpath", e.g. two usually correctly predicted branches plus the read most of the time. Then the >8 bits cpus arrived. That was ok, it just required to do the add to a u8 *, then convert to a u16/u32 * and do the read. At the asm level, it was all identical except for the final read, and read_byte/word/long being separate there was no test (and associated overhead) added in the path. Then the word-addressing CPUs arrived with, iirc, the tms cpus used in atari games. They require, to read from the pointer, to shift the address, either explicitely, or implicitely through indexing a u16 *. There were three possibilities: 1- create a new read_* method for each size and granularity. That amounts to a lot of copy/paste in the end, and functions with identical prototypes so the compiler can't detect you're using the wrong one. 2- put a variable shift in the read path. That was too expensive especially since the most critical cpus are byte-addressing (68000 at the time was the key). Having bit-adressing cpus which means the shift can either be right or left depending on the variable makes things even worse. 3- require the caller to do the shift himself when needed. The last solution was chosen, and starting that day the address was a byte offset and not the real address. Which is, actually, quite surprising when writing a new cpu core or, worse, when using the read/write methods from the driver code. But since then, C++ happened. And, in particular, templates with non-type parameters. Suddendly, solution 1 can be done without the copy/paste and with different types allowing to detect (at runtime, but systematically and at startup) if you got it wrong, while still generating optimal code. So it was time to switch to that solution and makes the address parameter sane again. Especially since it makes mucking in the rest of the memory subsystem code a lot more understandable.
* make device_memory_interface slightly less of a special case, use a typedef ↵ Vas Crabb2017-07-101-2/+2
| | | | to avoid nested templates everywhere (nw)
* dimemory: Lift the cap on the number of address spaces per device [O. Galibert] Olivier Galibert2017-07-031-2/+4
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* Move SEI80BU encryption out of the SEIBU_SOUND device and make it a device ↵ AJR2016-11-251-1/+12
| | | | | | of its own Add MCFG_DEVICE_ROM to override region tag for device_rom_interface (nw)
* Introduce u8/u16/u32/u64/s8/s16/s32/s64 Vas Crabb2016-11-191-6/+6
| | | | | | | | | | | | * New abbreviated types are in osd and util namespaces, and also in global namespace for things that #include "emu.h" * Get rid of import of cstdint types to global namespace (C99 does this anyway) * Remove the cstdint types from everything in emu * Get rid of U64/S64 macros * Fix a bug in dps16 caused by incorrect use of macro * Fix debugcon not checking for "do " prefix case-insensitively * Fix a lot of messed up tabulation * More constexpr * Fix up many __names
* NOTICE (TYPE NAME CONSOLIDATION) Miodrag Milanovic2016-10-221-6/+6
| | | | | Use standard uint64_t, uint32_t, uint16_t or uint8_t instead of UINT64, UINT32, UINT16 or UINT8 also use standard int64_t, int32_t, int16_t or int8_t instead of INT64, INT32, INT16 or INT8
* srcclean (nw) Vas Crabb2016-09-261-1/+0
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* okim6295: Directly use set_rom_bank [O. Galibert] Olivier Galibert2016-09-061-0/+5
| | | | dirom: Add a mandatory callback on bank change [O. Galibert]
* dirom: Resist to out-of-bounds bank numbers [O. Galibert] Olivier Galibert2016-09-061-4/+10
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* srcclean and translation regeneration Vas Crabb2016-08-291-3/+3
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* dirom fixes (nw) Olivier Galibert2016-08-271-1/+2
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* dirom,okim6295: Add/fix banking support. Better okim fix post-release [O. ↵ Olivier Galibert2016-08-251-7/+29
| | | | Galibert]
* dirom: Make robust to too big roms Olivier Galibert2016-08-161-28/+32
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* dirom: device_rom_interface for sound chips with rom/memory map alternative ↵ Olivier Galibert2016-08-151-0/+55
[O. Galibert]