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VarAction2: Ensure that a temp store var can't reference a clobbered var

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Jonathan G Rennison
2022-06-03 21:46:10 +01:00
parent fe6ab0f19f
commit 6ff8066d34
1 changed files with 15 additions and 0 deletions
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15
src/newgrf.cpp
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@@ -5773,6 +5773,15 @@ static void OptimiseVarAction2Adjust(VarAction2OptimiseState &state, const GrfSp
break;
}
if (adjust.operation == DSGA_OP_STOP) {
for (auto &it : state.temp_stores) {
/* Check if some other variable is marked as a copy of permanent storage */
if ((it.second.inference & VA2AIF_SINGLE_LOAD) && it.second.var_source.variable == 0x7C) {
it.second.inference &= ~VA2AIF_SINGLE_LOAD;
}
}
}
if ((feature >= GSF_TRAINS && feature <= GSF_AIRCRAFT) && IsExpensiveVehicleVariable(adjust.variable)) state.check_expensive_vars = true;
auto get_prev_single_load = [&]() -> const DeterministicSpriteGroupAdjust* {
@@ -6103,6 +6112,12 @@ static void OptimiseVarAction2Adjust(VarAction2OptimiseState &state, const GrfSp
if (adjust.variable == 0x1A && adjust.shift_num == 0) {
state.inference |= VA2AIF_PREV_STORE_TMP;
if (adjust.and_mask < 0x100) {
for (auto &it : state.temp_stores) {
/* Check if some other variable is marked as a copy of the one we are overwriting */
if ((it.second.inference & VA2AIF_SINGLE_LOAD) && it.second.var_source.variable == 0x7D && it.second.var_source.parameter == adjust.and_mask) {
it.second.inference &= ~VA2AIF_SINGLE_LOAD;
}
}
VarAction2TempStoreInference &store = state.temp_stores[adjust.and_mask];
store.inference = prev_inference & (~VA2AIF_PREV_MASK);
store.store_constant = state.current_constant;