early-access version 1255

externals/dynarmic/src/frontend/A32/decoder/arm.h

@@ -0,0 +1,53 @@
+/* This file is part of the dynarmic project.
+ * Copyright (c) 2016 MerryMage
+ * SPDX-License-Identifier: 0BSD
+ *
+ * Original version of table by Lioncash.
+ */
+
+#pragma once
+
+#include <algorithm>
+#include <functional>
+#include <optional>
+#include <vector>
+
+#include "common/bit_util.h"
+#include "common/common_types.h"
+#include "frontend/decoder/decoder_detail.h"
+#include "frontend/decoder/matcher.h"
+
+namespace Dynarmic::A32 {
+
+template <typename Visitor>
+using ArmMatcher = Decoder::Matcher<Visitor, u32>;
+
+template <typename V>
+std::vector<ArmMatcher<V>> GetArmDecodeTable() {
+    std::vector<ArmMatcher<V>> table = {
+
+#define INST(fn, name, bitstring) Decoder::detail::detail<ArmMatcher<V>>::GetMatcher(&V::fn, name, bitstring),
+#include "arm.inc"
+#undef INST
+
+    };
+
+    // If a matcher has more bits in its mask it is more specific, so it should come first.
+    std::stable_sort(table.begin(), table.end(), [](const auto& matcher1, const auto& matcher2) {
+        return Common::BitCount(matcher1.GetMask()) > Common::BitCount(matcher2.GetMask());
+    });
+
+    return table;
+}
+
+template<typename V>
+std::optional<std::reference_wrapper<const ArmMatcher<V>>> DecodeArm(u32 instruction) {
+    static const auto table = GetArmDecodeTable<V>();
+
+    const auto matches_instruction = [instruction](const auto& matcher) { return matcher.Matches(instruction); };
+
+    auto iter = std::find_if(table.begin(), table.end(), matches_instruction);
+    return iter != table.end() ? std::optional<std::reference_wrapper<const ArmMatcher<V>>>(*iter) : std::nullopt;
+}
+
+} // namespace Dynarmic::A32