User Config: Add option to specify wall clock CNTPCT.

This commit is contained in:
Fernando Sahmkow 2020-03-21 03:36:01 -04:00 committed by MerryMage
parent 97b9d3e058
commit 41521ed856
5 changed files with 14 additions and 3 deletions

View file

@ -200,6 +200,10 @@ struct UserConfig {
/// definite behaviour for some unpredictable instructions.
bool define_unpredictable_behaviour = false;
/// This tells the translator a wall clock will be used, thus allowing it
/// to avoid writting certain unnecessary code only needed for cycle timers.
bool wall_clock_cntpct = false;
/// This enables the fast dispatcher.
bool enable_fast_dispatch = true;

View file

@ -651,7 +651,9 @@ void A64EmitX64::EmitA64GetCNTFRQ(A64EmitContext& ctx, IR::Inst* inst) {
void A64EmitX64::EmitA64GetCNTPCT(A64EmitContext& ctx, IR::Inst* inst) {
ctx.reg_alloc.HostCall(inst);
code.UpdateTicks();
if (!conf.wall_clock_cntpct) {
code.UpdateTicks();
}
Devirtualize<&A64::UserCallbacks::GetCNTPCT>(conf.callbacks).EmitCall(code);
}

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@ -233,7 +233,8 @@ private:
// JIT Compile
const auto get_code = [this](u64 vaddr) { return conf.callbacks->MemoryReadCode(vaddr); };
IR::Block ir_block = A64::Translate(A64::LocationDescriptor{current_location}, get_code, {conf.define_unpredictable_behaviour});
IR::Block ir_block = A64::Translate(A64::LocationDescriptor{current_location}, get_code,
{conf.define_unpredictable_behaviour, conf.wall_clock_cntpct});
Optimization::A64CallbackConfigPass(ir_block, conf);
if (conf.enable_optimizations) {
Optimization::A64GetSetElimination(ir_block);

View file

@ -120,7 +120,7 @@ bool TranslatorVisitor::MRS(Imm<1> o0, Imm<3> op1, Imm<4> CRn, Imm<4> CRm, Imm<3
return true;
case SystemRegisterEncoding::CNTPCT_EL0:
// HACK: Ensure that this is the first instruction in the block it's emitted in, so the cycle count is most up-to-date.
if (!ir.block.empty()) {
if (!ir.block.empty() && !options.wall_clock_cntpct) {
ir.block.CycleCount()--;
ir.SetTerm(IR::Term::LinkBlock{*ir.current_location});
return false;

View file

@ -26,6 +26,10 @@ struct TranslationOptions {
/// If this is true, we define some behaviour for some instructions.
bool define_unpredictable_behaviour = false;
/// This tells the translator a wall clock will be used, thus allowing it
/// to avoid writting certain unnecessary code only needed for cycle timers.
bool wall_clock_cntpct = false;
/// This changes what IR we emit when we translate a hint instruction.
/// If this is false, we treat the instruction as a NOP.
/// If this is true, we emit an ExceptionRaised instruction.