Apple-2-Tools/apple2ix
1
0
Fork 0
mirror of https://github.com/mauiaaron/apple2.git synced 2025-01-12 06:29:58 +00:00
Code Issues Projects Releases Wiki Activity

Use 32bit counters to avoid overflow

Browse Source 
- Previously there were cases where we could overflow cpu65_cycles_to_execute when adding the cycles_speaker_feedback
This commit is contained in:
Aaron Culliney 2015-02-03 22:10:47 -08:00
parent 978011cffa
commit 851d22568b
4 changed files with 10 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
src/cpu.h
View File

@ -57,7 +57,7 @@ extern void *cpu65_vmem_w[65536];
extern unsigned char cpu65_flags_encode[256];
extern unsigned char cpu65_flags_decode[256];
extern int16_t cpu65_cycle_count;
extern int32_t cpu65_cycle_count;
#if CPU_TRACING
void cpu65_trace_begin(const char *trace_file);

4
src/test/testcpu.c
View File

@ -52,7 +52,9 @@ static void testcpu_setup(void *arg) {
//reinitialize();
cpu65_uninterrupt(0xff);
extern int16_t cpu65_cycles_to_execute;
extern int32_t cpu65_cycles_to_execute;
extern int32_t cpu65_cycle_count;
cpu65_cycle_count = 0;
cpu65_cycles_to_execute = 1;
cpu65_pc = TEST_LOC;

8
src/timing.c
View File

@ -54,9 +54,9 @@
double cycles_persec_target = CLK_6502;
unsigned long long cycles_count_total = 0;
int cycles_speaker_feedback = 0;
int16_t cpu65_cycles_to_execute = 0; // cycles-to-execute by cpu65_run()
int16_t cpu65_cycle_count = 0; // cycles currently excuted by cpu65_run()
static int16_t cycles_checkpoint_count = 0;
int32_t cpu65_cycles_to_execute = 0; // cycles-to-execute by cpu65_run()
int32_t cpu65_cycle_count = 0; // cycles currently excuted by cpu65_run()
static int32_t cycles_checkpoint_count = 0;
static unsigned int g_dwCyclesThisFrame = 0;
// scaling and speed adjustments
@ -370,7 +370,7 @@ unsigned int CpuGetCyclesThisVideoFrame(void) {
// Called when an IO-reg is accessed & accurate global cycle count info is needed
void timing_checkpoint_cycles(void) {
const int16_t d = cpu65_cycle_count - cycles_checkpoint_count;
const int32_t d = cpu65_cycle_count - cycles_checkpoint_count;
assert(d >= 0);
cycles_count_total += d;
cycles_checkpoint_count = cpu65_cycle_count;

4
src/x86/cpu.S
View File

@ -2155,10 +2155,10 @@ continue:
addb DebugCycleCount, %al
movb %al, DebugCycleCount
TRACE_EPILOGUE
addw %ax, SN(cpu65_cycle_count)
addl %eax, SN(cpu65_cycle_count)
subl %eax, SN(gc_cycles_timer_0)
subl %eax, SN(gc_cycles_timer_1)
subw %ax, SN(cpu65_cycles_to_execute)
subl %eax, SN(cpu65_cycles_to_execute)
jle exit_cpu65_run
continue1: xorLQ _XAX, _XAX
orb SN(cpu65__signal), %al