1 files changed, 45 insertions, 0 deletions

diff --git a/aisa/eval.h b/aisa/eval.h
new file mode 100644
index 0000000..f97740c
--- /dev/null
+++ b/aisa/eval.h
@@ -0,0 +1,45 @@
+#pragma once
+
+#include "aisa/aisa.h"
+
+namespace aisa {
+
+    template<typename CRTP> struct EvalState {
+        CRTP & crtp() noexcept { return static_cast<CRTP &>(*this); }
+
+        task<regval_t> async_load_reg(regnum_t rn)
+        {
+            while (true) {
+                if (auto rv = crtp().load_reg(rn); rv.has_value())
+                    co_return *rv;
+                co_await suspend();
+            }
+        }
+
+        task<void> async_store_reg(regnum_t rn, regval_t rv)
+        {
+            while (true) {
+                if (crtp().store_reg(rn, rv))
+                    co_return;
+                co_await suspend();
+            }
+        }
+
+        task<void> eval(const Step &step)
+        {
+            if (step.predicate.has_value()) {
+                regval_t pval = co_await async_load_reg(step.predicate->first);
+                if (pval != step.predicate->second)
+                    co_return;
+            }
+            std::vector<regval_t> source_vals;
+            source_vals.reserve(step.source_regs.size());
+            for (unsigned int i = 0; i < step.source_regs.size(); ++i)
+                source_vals.emplace_back(co_await async_load_reg(step.source_regs[i]));
+            auto destination_vals = step.compute_destinations(source_vals);
+            for (unsigned int i = 0; i < step.destination_regs.size(); ++i)
+                co_await async_store_reg(step.destination_regs[i], destination_vals[i]);
+        }
+    };
+
+}