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bsnes/higan/processor/m68k/memory.cpp

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Update to v100r08 release. byuu says: Six and a half hours this time ... one new opcode, and all old opcodes now in a deprecated format. Hooray, progress! For building the table, I've decided to move from: for(uint opcode : range(65536)) { if(match(...)) bind(opNAME, ...); } To instead having separate for loops for each supported opcode. This lets me specialize parts I want with templates. And to this aim, I'm moving to replace all of the (read,write)(size, ...) functions with (read,write)<Size>(...) functions. This will amount to the ~70ish instructions being triplicated ot ~210ish instructions; but I think this is really important. When I was getting into flag calculations, a ton of conditionals were needed to mask sizes to byte/word/long. There was also lots of conditionals in all the memory access handlers. The template code is ugly, but we eliminate a huge amount of branch conditions this way.
2016-07-17 22:11:29 +00:00
template<> auto M68K::read<Byte>(uint32 addr) -> uint32 {
step(4);
return read(0, addr);
}
template<> auto M68K::read<Word>(uint32 addr) -> uint32 {
step(4);
return read(1, addr);
}
template<> auto M68K::read<Long>(uint32 addr) -> uint32 {
step(4);
uint32 data = read(1, addr + 0) << 16;
step(4);
return data | read(1, addr + 2) << 0;
}
Update to v100r09 release. byuu says: Another six hours in ... I have all of the opcodes, memory access functions, disassembler mnemonics and table building converted over to the new template<uint Size> format. Certainly, it would be quite easy for this nightmare chip to throw me another curveball, but so far I can handle: - MOVE (EA to, EA from) case - read(from) has to update register index for +/-(aN) mode - MOVEM (EA from) case - when using +/-(aN), RA can't actually be updated until the transfer is completed - LEA (EA from) case - doesn't actually perform the final read; just returns the address to be read from - ANDI (EA from-and-to) case - same EA has to be read from and written to - for -(aN), the read has to come from aN-2, but can't update aN yet; so that the write also goes to aN-2 - no opcode can ever fetch the extension words more than once - manually control the order of extension word fetching order for proper opcode decoding To do all of that without a whole lot of duplicated code (or really bloating out every single instruction with red tape), I had to bring back the "bool valid / uint32 address" variables inside the EA struct =( If weird exceptions creep in like timing constraints only on certain opcodes, I can use template flags to the EA read/write functions to handle that.
2016-07-19 09:12:05 +00:00
//
template<> auto M68K::write<Byte>(uint32 addr, uint32 data) -> void {
Update to v100r10 release. byuu says: Redesigned the handling of reading/writing registers to be about eight times faster than the old system. More work may be needed ... it seems data registers tend to preserve their upper bits upon assignment; whereas address registers tend to sign-extend values into them. It may make sense to have DataRegister and AddressRegister classes with separate read/write handlers. I'd have to hold two Register objects inside the EffectiveAddress (EA) class if we do that. Implemented 19 opcodes now (out of somewhere between 60 and 90.) That gets the first ~530,000 instructions in Sonic the Hedgehog running (though probably wrong. But we can run a lot thanks to large initialization loops.) If I force the core to loop back to the reset vector on an invalid opcode, I'm getting about 1500fps with a dumb 320x240 blit 60 times a second and just the 68K running alone (no Z80, PSG, VDP, YM2612.) I don't know if that's good or not. I guess we'll find out. I had to stop tonight because the final opcode I execute is an RTS (return from subroutine) that's branching back to address 0; which is invalid ... meaning something went terribly wrong and the system crashed.
2016-07-22 12:03:25 +00:00
step(4);
return write(0, addr, data);
Update to v100r09 release. byuu says: Another six hours in ... I have all of the opcodes, memory access functions, disassembler mnemonics and table building converted over to the new template<uint Size> format. Certainly, it would be quite easy for this nightmare chip to throw me another curveball, but so far I can handle: - MOVE (EA to, EA from) case - read(from) has to update register index for +/-(aN) mode - MOVEM (EA from) case - when using +/-(aN), RA can't actually be updated until the transfer is completed - LEA (EA from) case - doesn't actually perform the final read; just returns the address to be read from - ANDI (EA from-and-to) case - same EA has to be read from and written to - for -(aN), the read has to come from aN-2, but can't update aN yet; so that the write also goes to aN-2 - no opcode can ever fetch the extension words more than once - manually control the order of extension word fetching order for proper opcode decoding To do all of that without a whole lot of duplicated code (or really bloating out every single instruction with red tape), I had to bring back the "bool valid / uint32 address" variables inside the EA struct =( If weird exceptions creep in like timing constraints only on certain opcodes, I can use template flags to the EA read/write functions to handle that.
2016-07-19 09:12:05 +00:00
}
template<> auto M68K::write<Word>(uint32 addr, uint32 data) -> void {
Update to v100r10 release. byuu says: Redesigned the handling of reading/writing registers to be about eight times faster than the old system. More work may be needed ... it seems data registers tend to preserve their upper bits upon assignment; whereas address registers tend to sign-extend values into them. It may make sense to have DataRegister and AddressRegister classes with separate read/write handlers. I'd have to hold two Register objects inside the EffectiveAddress (EA) class if we do that. Implemented 19 opcodes now (out of somewhere between 60 and 90.) That gets the first ~530,000 instructions in Sonic the Hedgehog running (though probably wrong. But we can run a lot thanks to large initialization loops.) If I force the core to loop back to the reset vector on an invalid opcode, I'm getting about 1500fps with a dumb 320x240 blit 60 times a second and just the 68K running alone (no Z80, PSG, VDP, YM2612.) I don't know if that's good or not. I guess we'll find out. I had to stop tonight because the final opcode I execute is an RTS (return from subroutine) that's branching back to address 0; which is invalid ... meaning something went terribly wrong and the system crashed.
2016-07-22 12:03:25 +00:00
step(4);
return write(1, addr, data);
Update to v100r09 release. byuu says: Another six hours in ... I have all of the opcodes, memory access functions, disassembler mnemonics and table building converted over to the new template<uint Size> format. Certainly, it would be quite easy for this nightmare chip to throw me another curveball, but so far I can handle: - MOVE (EA to, EA from) case - read(from) has to update register index for +/-(aN) mode - MOVEM (EA from) case - when using +/-(aN), RA can't actually be updated until the transfer is completed - LEA (EA from) case - doesn't actually perform the final read; just returns the address to be read from - ANDI (EA from-and-to) case - same EA has to be read from and written to - for -(aN), the read has to come from aN-2, but can't update aN yet; so that the write also goes to aN-2 - no opcode can ever fetch the extension words more than once - manually control the order of extension word fetching order for proper opcode decoding To do all of that without a whole lot of duplicated code (or really bloating out every single instruction with red tape), I had to bring back the "bool valid / uint32 address" variables inside the EA struct =( If weird exceptions creep in like timing constraints only on certain opcodes, I can use template flags to the EA read/write functions to handle that.
2016-07-19 09:12:05 +00:00
}
template<> auto M68K::write<Long>(uint32 addr, uint32 data) -> void {
Update to v100r10 release. byuu says: Redesigned the handling of reading/writing registers to be about eight times faster than the old system. More work may be needed ... it seems data registers tend to preserve their upper bits upon assignment; whereas address registers tend to sign-extend values into them. It may make sense to have DataRegister and AddressRegister classes with separate read/write handlers. I'd have to hold two Register objects inside the EffectiveAddress (EA) class if we do that. Implemented 19 opcodes now (out of somewhere between 60 and 90.) That gets the first ~530,000 instructions in Sonic the Hedgehog running (though probably wrong. But we can run a lot thanks to large initialization loops.) If I force the core to loop back to the reset vector on an invalid opcode, I'm getting about 1500fps with a dumb 320x240 blit 60 times a second and just the 68K running alone (no Z80, PSG, VDP, YM2612.) I don't know if that's good or not. I guess we'll find out. I had to stop tonight because the final opcode I execute is an RTS (return from subroutine) that's branching back to address 0; which is invalid ... meaning something went terribly wrong and the system crashed.
2016-07-22 12:03:25 +00:00
step(4);
write(1, addr + 0, data >> 16);
step(4);
write(1, addr + 2, data >> 0);
}
template<> auto M68K::write<Byte, Reverse>(uint32 addr, uint32 data) -> void {
step(4);
return write(0, addr, data);
}
template<> auto M68K::write<Word, Reverse>(uint32 addr, uint32 data) -> void {
step(4);
return write(1, addr, data);
}
template<> auto M68K::write<Long, Reverse>(uint32 addr, uint32 data) -> void {
step(4);
write(1, addr + 2, data >> 0);
step(4);
write(1, addr + 0, data >> 16);
Update to v100r09 release. byuu says: Another six hours in ... I have all of the opcodes, memory access functions, disassembler mnemonics and table building converted over to the new template<uint Size> format. Certainly, it would be quite easy for this nightmare chip to throw me another curveball, but so far I can handle: - MOVE (EA to, EA from) case - read(from) has to update register index for +/-(aN) mode - MOVEM (EA from) case - when using +/-(aN), RA can't actually be updated until the transfer is completed - LEA (EA from) case - doesn't actually perform the final read; just returns the address to be read from - ANDI (EA from-and-to) case - same EA has to be read from and written to - for -(aN), the read has to come from aN-2, but can't update aN yet; so that the write also goes to aN-2 - no opcode can ever fetch the extension words more than once - manually control the order of extension word fetching order for proper opcode decoding To do all of that without a whole lot of duplicated code (or really bloating out every single instruction with red tape), I had to bring back the "bool valid / uint32 address" variables inside the EA struct =( If weird exceptions creep in like timing constraints only on certain opcodes, I can use template flags to the EA read/write functions to handle that.
2016-07-19 09:12:05 +00:00
}
//
template<> auto M68K::readPC<Byte>() -> uint32 {
step(4);
Update to v100r10 release. byuu says: Redesigned the handling of reading/writing registers to be about eight times faster than the old system. More work may be needed ... it seems data registers tend to preserve their upper bits upon assignment; whereas address registers tend to sign-extend values into them. It may make sense to have DataRegister and AddressRegister classes with separate read/write handlers. I'd have to hold two Register objects inside the EffectiveAddress (EA) class if we do that. Implemented 19 opcodes now (out of somewhere between 60 and 90.) That gets the first ~530,000 instructions in Sonic the Hedgehog running (though probably wrong. But we can run a lot thanks to large initialization loops.) If I force the core to loop back to the reset vector on an invalid opcode, I'm getting about 1500fps with a dumb 320x240 blit 60 times a second and just the 68K running alone (no Z80, PSG, VDP, YM2612.) I don't know if that's good or not. I guess we'll find out. I had to stop tonight because the final opcode I execute is an RTS (return from subroutine) that's branching back to address 0; which is invalid ... meaning something went terribly wrong and the system crashed.
2016-07-22 12:03:25 +00:00
auto data = read(1, r.pc);
Update to v100r09 release. byuu says: Another six hours in ... I have all of the opcodes, memory access functions, disassembler mnemonics and table building converted over to the new template<uint Size> format. Certainly, it would be quite easy for this nightmare chip to throw me another curveball, but so far I can handle: - MOVE (EA to, EA from) case - read(from) has to update register index for +/-(aN) mode - MOVEM (EA from) case - when using +/-(aN), RA can't actually be updated until the transfer is completed - LEA (EA from) case - doesn't actually perform the final read; just returns the address to be read from - ANDI (EA from-and-to) case - same EA has to be read from and written to - for -(aN), the read has to come from aN-2, but can't update aN yet; so that the write also goes to aN-2 - no opcode can ever fetch the extension words more than once - manually control the order of extension word fetching order for proper opcode decoding To do all of that without a whole lot of duplicated code (or really bloating out every single instruction with red tape), I had to bring back the "bool valid / uint32 address" variables inside the EA struct =( If weird exceptions creep in like timing constraints only on certain opcodes, I can use template flags to the EA read/write functions to handle that.
2016-07-19 09:12:05 +00:00
r.pc += 2;
return (uint8)data;
}
template<> auto M68K::readPC<Word>() -> uint32 {
step(4);
Update to v100r10 release. byuu says: Redesigned the handling of reading/writing registers to be about eight times faster than the old system. More work may be needed ... it seems data registers tend to preserve their upper bits upon assignment; whereas address registers tend to sign-extend values into them. It may make sense to have DataRegister and AddressRegister classes with separate read/write handlers. I'd have to hold two Register objects inside the EffectiveAddress (EA) class if we do that. Implemented 19 opcodes now (out of somewhere between 60 and 90.) That gets the first ~530,000 instructions in Sonic the Hedgehog running (though probably wrong. But we can run a lot thanks to large initialization loops.) If I force the core to loop back to the reset vector on an invalid opcode, I'm getting about 1500fps with a dumb 320x240 blit 60 times a second and just the 68K running alone (no Z80, PSG, VDP, YM2612.) I don't know if that's good or not. I guess we'll find out. I had to stop tonight because the final opcode I execute is an RTS (return from subroutine) that's branching back to address 0; which is invalid ... meaning something went terribly wrong and the system crashed.
2016-07-22 12:03:25 +00:00
auto data = read(1, r.pc);
Update to v100r09 release. byuu says: Another six hours in ... I have all of the opcodes, memory access functions, disassembler mnemonics and table building converted over to the new template<uint Size> format. Certainly, it would be quite easy for this nightmare chip to throw me another curveball, but so far I can handle: - MOVE (EA to, EA from) case - read(from) has to update register index for +/-(aN) mode - MOVEM (EA from) case - when using +/-(aN), RA can't actually be updated until the transfer is completed - LEA (EA from) case - doesn't actually perform the final read; just returns the address to be read from - ANDI (EA from-and-to) case - same EA has to be read from and written to - for -(aN), the read has to come from aN-2, but can't update aN yet; so that the write also goes to aN-2 - no opcode can ever fetch the extension words more than once - manually control the order of extension word fetching order for proper opcode decoding To do all of that without a whole lot of duplicated code (or really bloating out every single instruction with red tape), I had to bring back the "bool valid / uint32 address" variables inside the EA struct =( If weird exceptions creep in like timing constraints only on certain opcodes, I can use template flags to the EA read/write functions to handle that.
2016-07-19 09:12:05 +00:00
r.pc += 2;
return data;
}
template<> auto M68K::readPC<Long>() -> uint32 {
step(4);
Update to v100r10 release. byuu says: Redesigned the handling of reading/writing registers to be about eight times faster than the old system. More work may be needed ... it seems data registers tend to preserve their upper bits upon assignment; whereas address registers tend to sign-extend values into them. It may make sense to have DataRegister and AddressRegister classes with separate read/write handlers. I'd have to hold two Register objects inside the EffectiveAddress (EA) class if we do that. Implemented 19 opcodes now (out of somewhere between 60 and 90.) That gets the first ~530,000 instructions in Sonic the Hedgehog running (though probably wrong. But we can run a lot thanks to large initialization loops.) If I force the core to loop back to the reset vector on an invalid opcode, I'm getting about 1500fps with a dumb 320x240 blit 60 times a second and just the 68K running alone (no Z80, PSG, VDP, YM2612.) I don't know if that's good or not. I guess we'll find out. I had to stop tonight because the final opcode I execute is an RTS (return from subroutine) that's branching back to address 0; which is invalid ... meaning something went terribly wrong and the system crashed.
2016-07-22 12:03:25 +00:00
auto hi = read(1, r.pc);
Update to v100r09 release. byuu says: Another six hours in ... I have all of the opcodes, memory access functions, disassembler mnemonics and table building converted over to the new template<uint Size> format. Certainly, it would be quite easy for this nightmare chip to throw me another curveball, but so far I can handle: - MOVE (EA to, EA from) case - read(from) has to update register index for +/-(aN) mode - MOVEM (EA from) case - when using +/-(aN), RA can't actually be updated until the transfer is completed - LEA (EA from) case - doesn't actually perform the final read; just returns the address to be read from - ANDI (EA from-and-to) case - same EA has to be read from and written to - for -(aN), the read has to come from aN-2, but can't update aN yet; so that the write also goes to aN-2 - no opcode can ever fetch the extension words more than once - manually control the order of extension word fetching order for proper opcode decoding To do all of that without a whole lot of duplicated code (or really bloating out every single instruction with red tape), I had to bring back the "bool valid / uint32 address" variables inside the EA struct =( If weird exceptions creep in like timing constraints only on certain opcodes, I can use template flags to the EA read/write functions to handle that.
2016-07-19 09:12:05 +00:00
r.pc += 2;
step(4);
Update to v100r10 release. byuu says: Redesigned the handling of reading/writing registers to be about eight times faster than the old system. More work may be needed ... it seems data registers tend to preserve their upper bits upon assignment; whereas address registers tend to sign-extend values into them. It may make sense to have DataRegister and AddressRegister classes with separate read/write handlers. I'd have to hold two Register objects inside the EffectiveAddress (EA) class if we do that. Implemented 19 opcodes now (out of somewhere between 60 and 90.) That gets the first ~530,000 instructions in Sonic the Hedgehog running (though probably wrong. But we can run a lot thanks to large initialization loops.) If I force the core to loop back to the reset vector on an invalid opcode, I'm getting about 1500fps with a dumb 320x240 blit 60 times a second and just the 68K running alone (no Z80, PSG, VDP, YM2612.) I don't know if that's good or not. I guess we'll find out. I had to stop tonight because the final opcode I execute is an RTS (return from subroutine) that's branching back to address 0; which is invalid ... meaning something went terribly wrong and the system crashed.
2016-07-22 12:03:25 +00:00
auto lo = read(1, r.pc);
Update to v100r09 release. byuu says: Another six hours in ... I have all of the opcodes, memory access functions, disassembler mnemonics and table building converted over to the new template<uint Size> format. Certainly, it would be quite easy for this nightmare chip to throw me another curveball, but so far I can handle: - MOVE (EA to, EA from) case - read(from) has to update register index for +/-(aN) mode - MOVEM (EA from) case - when using +/-(aN), RA can't actually be updated until the transfer is completed - LEA (EA from) case - doesn't actually perform the final read; just returns the address to be read from - ANDI (EA from-and-to) case - same EA has to be read from and written to - for -(aN), the read has to come from aN-2, but can't update aN yet; so that the write also goes to aN-2 - no opcode can ever fetch the extension words more than once - manually control the order of extension word fetching order for proper opcode decoding To do all of that without a whole lot of duplicated code (or really bloating out every single instruction with red tape), I had to bring back the "bool valid / uint32 address" variables inside the EA struct =( If weird exceptions creep in like timing constraints only on certain opcodes, I can use template flags to the EA read/write functions to handle that.
2016-07-19 09:12:05 +00:00
r.pc += 2;
Update to v100r10 release. byuu says: Redesigned the handling of reading/writing registers to be about eight times faster than the old system. More work may be needed ... it seems data registers tend to preserve their upper bits upon assignment; whereas address registers tend to sign-extend values into them. It may make sense to have DataRegister and AddressRegister classes with separate read/write handlers. I'd have to hold two Register objects inside the EffectiveAddress (EA) class if we do that. Implemented 19 opcodes now (out of somewhere between 60 and 90.) That gets the first ~530,000 instructions in Sonic the Hedgehog running (though probably wrong. But we can run a lot thanks to large initialization loops.) If I force the core to loop back to the reset vector on an invalid opcode, I'm getting about 1500fps with a dumb 320x240 blit 60 times a second and just the 68K running alone (no Z80, PSG, VDP, YM2612.) I don't know if that's good or not. I guess we'll find out. I had to stop tonight because the final opcode I execute is an RTS (return from subroutine) that's branching back to address 0; which is invalid ... meaning something went terribly wrong and the system crashed.
2016-07-22 12:03:25 +00:00
return hi << 16 | lo << 0;
}
//
template<uint Size> auto M68K::pop() -> uint32 {
Update to v100r11 release. byuu says: I split the Register class and read/write handlers into DataRegister and AddressRegister, given that they have different behaviors on byte/word accesses (data tends to preserve the upper bits; address tends to sign-extend things.) I expanded EA to EffectiveAddress. No sense in abbreviating things to death. I've now implemented 26 instructions. But the new ones are just all the stupid from/to ccr/sr instructions. Ryphecha confirmed that you can't set the undefined bits, so I don't think the BitField concept is appropriate for the CCR/SR. Instead, I'm just storing direct flags and have (read,write)(CCR,SR) instead. This isn't like the 65816 where you have subroutines that push and pop the flag register. It's much more common to access individual flags. Doesn't match the consistency angle of the other CPU cores, but ... I think this is the right thing to for the 68K specifically.
2016-07-23 02:32:35 +00:00
auto data = read<Size>((uint32)r.a[7]);
r.a[7] += Size == Long ? 4 : 2;
Update to v100r09 release. byuu says: Another six hours in ... I have all of the opcodes, memory access functions, disassembler mnemonics and table building converted over to the new template<uint Size> format. Certainly, it would be quite easy for this nightmare chip to throw me another curveball, but so far I can handle: - MOVE (EA to, EA from) case - read(from) has to update register index for +/-(aN) mode - MOVEM (EA from) case - when using +/-(aN), RA can't actually be updated until the transfer is completed - LEA (EA from) case - doesn't actually perform the final read; just returns the address to be read from - ANDI (EA from-and-to) case - same EA has to be read from and written to - for -(aN), the read has to come from aN-2, but can't update aN yet; so that the write also goes to aN-2 - no opcode can ever fetch the extension words more than once - manually control the order of extension word fetching order for proper opcode decoding To do all of that without a whole lot of duplicated code (or really bloating out every single instruction with red tape), I had to bring back the "bool valid / uint32 address" variables inside the EA struct =( If weird exceptions creep in like timing constraints only on certain opcodes, I can use template flags to the EA read/write functions to handle that.
2016-07-19 09:12:05 +00:00
return data;
}
Update to v100r10 release. byuu says: Redesigned the handling of reading/writing registers to be about eight times faster than the old system. More work may be needed ... it seems data registers tend to preserve their upper bits upon assignment; whereas address registers tend to sign-extend values into them. It may make sense to have DataRegister and AddressRegister classes with separate read/write handlers. I'd have to hold two Register objects inside the EffectiveAddress (EA) class if we do that. Implemented 19 opcodes now (out of somewhere between 60 and 90.) That gets the first ~530,000 instructions in Sonic the Hedgehog running (though probably wrong. But we can run a lot thanks to large initialization loops.) If I force the core to loop back to the reset vector on an invalid opcode, I'm getting about 1500fps with a dumb 320x240 blit 60 times a second and just the 68K running alone (no Z80, PSG, VDP, YM2612.) I don't know if that's good or not. I guess we'll find out. I had to stop tonight because the final opcode I execute is an RTS (return from subroutine) that's branching back to address 0; which is invalid ... meaning something went terribly wrong and the system crashed.
2016-07-22 12:03:25 +00:00
template<uint Size> auto M68K::push(uint32 data) -> void {
Update to v100r11 release. byuu says: I split the Register class and read/write handlers into DataRegister and AddressRegister, given that they have different behaviors on byte/word accesses (data tends to preserve the upper bits; address tends to sign-extend things.) I expanded EA to EffectiveAddress. No sense in abbreviating things to death. I've now implemented 26 instructions. But the new ones are just all the stupid from/to ccr/sr instructions. Ryphecha confirmed that you can't set the undefined bits, so I don't think the BitField concept is appropriate for the CCR/SR. Instead, I'm just storing direct flags and have (read,write)(CCR,SR) instead. This isn't like the 65816 where you have subroutines that push and pop the flag register. It's much more common to access individual flags. Doesn't match the consistency angle of the other CPU cores, but ... I think this is the right thing to for the 68K specifically.
2016-07-23 02:32:35 +00:00
r.a[7] -= Size == Long ? 4 : 2;
return write<Size, Reverse>((uint32)r.a[7], data);
Update to v100r10 release. byuu says: Redesigned the handling of reading/writing registers to be about eight times faster than the old system. More work may be needed ... it seems data registers tend to preserve their upper bits upon assignment; whereas address registers tend to sign-extend values into them. It may make sense to have DataRegister and AddressRegister classes with separate read/write handlers. I'd have to hold two Register objects inside the EffectiveAddress (EA) class if we do that. Implemented 19 opcodes now (out of somewhere between 60 and 90.) That gets the first ~530,000 instructions in Sonic the Hedgehog running (though probably wrong. But we can run a lot thanks to large initialization loops.) If I force the core to loop back to the reset vector on an invalid opcode, I'm getting about 1500fps with a dumb 320x240 blit 60 times a second and just the 68K running alone (no Z80, PSG, VDP, YM2612.) I don't know if that's good or not. I guess we'll find out. I had to stop tonight because the final opcode I execute is an RTS (return from subroutine) that's branching back to address 0; which is invalid ... meaning something went terribly wrong and the system crashed.
2016-07-22 12:03:25 +00:00
}