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GBA Memory: Clean up stall function slightly

This commit is contained in:
Vicki Pfau 2023-03-20 21:11:57 -07:00
parent 603c1800d5
commit 646a0e9b33
1 changed files with 4 additions and 6 deletions
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10
src/gba/memory.c
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@ -1747,15 +1747,13 @@ int32_t GBAMemoryStall(struct ARMCore* cpu, int32_t wait) {
maxLoads -= previousLoads; maxLoads -= previousLoads;
} }
int32_t s = cpu->memory.activeSeqCycles16;
int32_t n2s = cpu->memory.activeNonseqCycles16 - cpu->memory.activeSeqCycles16 + 1;
// Figure out how many sequential loads we can jam in // Figure out how many sequential loads we can jam in
int32_t s = cpu->memory.activeSeqCycles16;
int32_t stall = s + 1; int32_t stall = s + 1;
int32_t loads = 1; int32_t loads = 1;
while (stall < wait && loads < maxLoads) { while (stall < wait && loads < maxLoads) {
stall += s; stall += s + 1;
++loads; ++loads;
} }
memory->lastPrefetchedPc = cpu->gprs[ARM_PC] + WORD_SIZE_THUMB * (loads + previousLoads - 1); memory->lastPrefetchedPc = cpu->gprs[ARM_PC] + WORD_SIZE_THUMB * (loads + previousLoads - 1);
@ -1766,10 +1764,10 @@ int32_t GBAMemoryStall(struct ARMCore* cpu, int32_t wait) {
} }
// This instruction used to have an N, convert it to an S. // This instruction used to have an N, convert it to an S.
wait -= n2s; wait -= cpu->memory.activeNonseqCycles16 - s;
// The next |loads|S waitstates disappear entirely, so long as they're all in a row // The next |loads|S waitstates disappear entirely, so long as they're all in a row
wait -= stall - 1; wait -= stall;
return wait; return wait;
} }