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Rewrote timer code.

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The new code is based on timestamps, rather than delays. This eliminates the
need to update every timer in timer_process(), which cost a non-trivial amount
of CPU time on low-end machines.

This involved changes to every user of the timer code, so this change almost
certainly introduces bugs.
This commit is contained in:
SarahW 2018-08-02 22:06:10 +01:00
commit a7d006b637
79 changed files with 1050 additions and 1033 deletions
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18
src/808x.c
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@ -25,7 +25,7 @@
#include "x87.h"
#include "paths.h"
int xt_cpu_multi;
uint64_t xt_cpu_multi;
int nmi = 0;
int nmi_auto_clear = 0;
@ -821,13 +821,24 @@ static void setsbc16(uint16_t a, uint16_t b)
}
int current_diff = 0;
/*XT systems use the XT master oscillator (14.318 MHz) rather than the CPU clock
at the base timer frequency. Because there isn't an integer relationship
between the two frequencies, use fixed point arithmetic when updating TSC.*/
static uint64_t tsc_frac = 0;
void clockhardware()
{
int diff = cycdiff - cycles - current_diff;
current_diff += diff;
timer_end_period(cycles*xt_cpu_multi);
tsc_frac += (uint64_t)diff * xt_cpu_multi;
tsc += (tsc_frac >> 32);
tsc_frac &= 0xffffffff;
if (TIMER_VAL_LESS_THAN_VAL(timer_target, (uint32_t)tsc))
timer_process();
}
static int takeint = 0;
@ -1104,7 +1115,6 @@ void execx86(int cycs)
// if (pc==0x96B && cs==0x9E040) { printf("Hit it\n"); output=1; timetolive=150; }
// if (pc<0x8000) printf("%04X : %04X %04X %04X %04X %04X %04X %04X %04X %04X %04X %04X %04X %02X %04X %i\n",pc,AX,BX,CX,DX,cs>>4,ds>>4,es>>4,ss>>4,DI,SI,BP,SP,opcode,flags,disctime);
cycdiff=cycles;
timer_start_period(cycles*xt_cpu_multi);
current_diff = 0;
cycles-=nextcyc;
// if (instime) pclog("Cycles %i %i\n",cycles,cycdiff);