From 6d292e3eac44478ae36d766e1e8f745ede38410b Mon Sep 17 00:00:00 2001
From: MerryMage <MerryMage@users.noreply.github.com>
Date: Mon, 3 May 2021 13:00:40 +0100
Subject: [PATCH] decoder: Ensure more compiler-time computation
Replace with consteval when C++20 hits
---
src/frontend/A32/decoder/arm.h | 2 +-
src/frontend/A32/decoder/asimd.h | 2 +-
src/frontend/A32/decoder/thumb16.h | 2 +-
src/frontend/A32/decoder/thumb32.h | 2 +-
src/frontend/A32/decoder/vfp.h | 2 +-
src/frontend/A64/decoder/a64.h | 18 ++++++++--------
src/frontend/decoder/decoder_detail.h | 31 +++++++++++++++++----------
7 files changed, 34 insertions(+), 25 deletions(-)
diff --git a/src/frontend/A32/decoder/arm.h b/src/frontend/A32/decoder/arm.h
index 184ae30a..442fe67d 100644
--- a/src/frontend/A32/decoder/arm.h
+++ b/src/frontend/A32/decoder/arm.h
@@ -26,7 +26,7 @@ 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),
+#define INST(fn, name, bitstring) DYNARMIC_DECODER_GET_MATCHER(ArmMatcher, fn, name, Decoder::detail::StringToArray<32>(bitstring)),
#include "arm.inc"
#undef INST
diff --git a/src/frontend/A32/decoder/asimd.h b/src/frontend/A32/decoder/asimd.h
index 5316430a..07fb0f71 100644
--- a/src/frontend/A32/decoder/asimd.h
+++ b/src/frontend/A32/decoder/asimd.h
@@ -25,7 +25,7 @@ template <typename V>
std::vector<ASIMDMatcher<V>> GetASIMDDecodeTable() {
std::vector<ASIMDMatcher<V>> table = {
-#define INST(fn, name, bitstring) Decoder::detail::detail<ASIMDMatcher<V>>::GetMatcher(&V::fn, name, bitstring),
+#define INST(fn, name, bitstring) DYNARMIC_DECODER_GET_MATCHER(ASIMDMatcher, fn, name, Decoder::detail::StringToArray<32>(bitstring)),
#include "asimd.inc"
#undef INST
diff --git a/src/frontend/A32/decoder/thumb16.h b/src/frontend/A32/decoder/thumb16.h
index d2dfb863..b1ce7446 100644
--- a/src/frontend/A32/decoder/thumb16.h
+++ b/src/frontend/A32/decoder/thumb16.h
@@ -23,7 +23,7 @@ template<typename V>
std::optional<std::reference_wrapper<const Thumb16Matcher<V>>> DecodeThumb16(u16 instruction) {
static const std::vector<Thumb16Matcher<V>> table = {
-#define INST(fn, name, bitstring) Decoder::detail::detail<Thumb16Matcher<V>>::GetMatcher(&V::fn, name, bitstring),
+#define INST(fn, name, bitstring) DYNARMIC_DECODER_GET_MATCHER(Thumb16Matcher, fn, name, Decoder::detail::StringToArray<16>(bitstring)),
#include "thumb16.inc"
#undef INST
diff --git a/src/frontend/A32/decoder/thumb32.h b/src/frontend/A32/decoder/thumb32.h
index a0dd4333..dc370a31 100644
--- a/src/frontend/A32/decoder/thumb32.h
+++ b/src/frontend/A32/decoder/thumb32.h
@@ -22,7 +22,7 @@ template<typename V>
std::optional<std::reference_wrapper<const Thumb32Matcher<V>>> DecodeThumb32(u32 instruction) {
static const std::vector<Thumb32Matcher<V>> table = {
-#define INST(fn, name, bitstring) Decoder::detail::detail<Thumb32Matcher<V>>::GetMatcher(&V::fn, name, bitstring),
+#define INST(fn, name, bitstring) DYNARMIC_DECODER_GET_MATCHER(Thumb32Matcher, fn, name, Decoder::detail::StringToArray<32>(bitstring)),
#include "thumb32.inc"
#undef INST
diff --git a/src/frontend/A32/decoder/vfp.h b/src/frontend/A32/decoder/vfp.h
index 2b78c66e..1abfc67a 100644
--- a/src/frontend/A32/decoder/vfp.h
+++ b/src/frontend/A32/decoder/vfp.h
@@ -30,7 +30,7 @@ std::optional<std::reference_wrapper<const VFPMatcher<V>>> DecodeVFP(u32 instruc
} tables = []{
Table list = {
-#define INST(fn, name, bitstring) Decoder::detail::detail<VFPMatcher<V>>::GetMatcher(&V::fn, name, bitstring),
+#define INST(fn, name, bitstring) DYNARMIC_DECODER_GET_MATCHER(VFPMatcher, fn, name, Decoder::detail::StringToArray<32>(bitstring)),
#include "vfp.inc"
#undef INST
diff --git a/src/frontend/A64/decoder/a64.h b/src/frontend/A64/decoder/a64.h
index 0379c32c..d3dc0cf6 100644
--- a/src/frontend/A64/decoder/a64.h
+++ b/src/frontend/A64/decoder/a64.h
@@ -31,10 +31,10 @@ inline size_t ToFastLookupIndex(u32 instruction) {
}
} // namespace detail
-template <typename Visitor>
-DecodeTable<Visitor> GetDecodeTable() {
- std::vector<Matcher<Visitor>> list = {
-#define INST(fn, name, bitstring) Decoder::detail::detail<Matcher<Visitor>>::GetMatcher(&Visitor::fn, name, bitstring),
+template <typename V>
+DecodeTable<V> GetDecodeTable() {
+ std::vector<Matcher<V>> list = {
+#define INST(fn, name, bitstring) DYNARMIC_DECODER_GET_MATCHER(Matcher, fn, name, Decoder::detail::StringToArray<32>(bitstring)),
#include "a64.inc"
#undef INST
};
@@ -55,7 +55,7 @@ DecodeTable<Visitor> GetDecodeTable() {
return comes_first.count(matcher.GetName()) > 0;
});
- DecodeTable<Visitor> table{};
+ DecodeTable<V> table{};
for (size_t i = 0; i < table.size(); ++i) {
for (auto matcher : list) {
const auto expect = detail::ToFastLookupIndex(matcher.GetExpected());
@@ -68,15 +68,15 @@ DecodeTable<Visitor> GetDecodeTable() {
return table;
}
-template<typename Visitor>
-std::optional<std::reference_wrapper<const Matcher<Visitor>>> Decode(u32 instruction) {
- static const auto table = GetDecodeTable<Visitor>();
+template<typename V>
+std::optional<std::reference_wrapper<const Matcher<V>>> Decode(u32 instruction) {
+ static const auto table = GetDecodeTable<V>();
const auto matches_instruction = [instruction](const auto& matcher) { return matcher.Matches(instruction); };
const auto& subtable = table[detail::ToFastLookupIndex(instruction)];
auto iter = std::find_if(subtable.begin(), subtable.end(), matches_instruction);
- return iter != subtable.end() ? std::optional<std::reference_wrapper<const Matcher<Visitor>>>(*iter) : std::nullopt;
+ return iter != subtable.end() ? std::optional<std::reference_wrapper<const Matcher<V>>>(*iter) : std::nullopt;
}
} // namespace Dynarmic::A64
diff --git a/src/frontend/decoder/decoder_detail.h b/src/frontend/decoder/decoder_detail.h
index 4f41929e..124b1f57 100644
--- a/src/frontend/decoder/decoder_detail.h
+++ b/src/frontend/decoder/decoder_detail.h
@@ -17,6 +17,15 @@
namespace Dynarmic::Decoder {
namespace detail {
+template <size_t N>
+inline constexpr std::array<char, N> StringToArray(const char (&str)[N + 1]) {
+ std::array<char, N> result;
+ for (size_t i = 0; i < N; i++) {
+ result[i] = str[i];
+ }
+ return result;
+}
+
/**
* Helper functions for the decoders.
*
@@ -24,7 +33,6 @@ namespace detail {
*/
template<class MatcherT>
struct detail {
-private:
using opcode_type = typename MatcherT::opcode_type;
using visitor_type = typename MatcherT::visitor_type;
@@ -35,7 +43,7 @@ private:
* A '0' in a bitstring indicates that a zero must be present at that bit position.
* A '1' in a bitstring indicates that a one must be present at that bit position.
*/
- static constexpr auto GetMaskAndExpect(const char* const bitstring) {
+ static constexpr auto GetMaskAndExpect(std::array<char, opcode_bitsize> bitstring) {
const auto one = static_cast<opcode_type>(1);
opcode_type mask = 0, expect = 0;
for (size_t i = 0; i < opcode_bitsize; i++) {
@@ -62,7 +70,7 @@ private:
* An argument is specified by a continuous string of the same character.
*/
template<size_t N>
- static auto GetArgInfo(const char* const bitstring) {
+ static constexpr auto GetArgInfo(std::array<char, opcode_bitsize> bitstring) {
std::array<opcode_type, N> masks = {};
std::array<size_t, N> shifts = {};
size_t arg_index = 0;
@@ -85,11 +93,12 @@ private:
if constexpr (N > 0) {
const size_t bit_position = opcode_bitsize - i - 1;
- ASSERT(arg_index < N);
+ if (arg_index >= N) throw std::out_of_range("Unexpected field");
+
masks[arg_index] |= static_cast<opcode_type>(1) << bit_position;
shifts[arg_index] = bit_position;
} else {
- ASSERT_FALSE();
+ throw std::out_of_range("Unexpected field");
}
}
}
@@ -148,23 +157,23 @@ private:
#pragma warning(pop)
#endif
-public:
/**
* Creates a matcher that can match and parse instructions based on bitstring.
* See also: GetMaskAndExpect and GetArgInfo for format of bitstring.
*/
- template<typename FnT>
- static auto GetMatcher(FnT fn, const char* const name, const char* const bitstring) {
- constexpr size_t args_count = mp::parameter_count_v<FnT>;
+ template<typename FnT, size_t args_count = mp::parameter_count_v<FnT>>
+ static auto GetMatcher(FnT fn, const char* const name, std::tuple<opcode_type, opcode_type> mask_and_expect, std::tuple<std::array<opcode_type, args_count>, std::array<size_t, args_count>> masks_and_shifts) {
using Iota = std::make_index_sequence<args_count>;
- const auto [mask, expect] = GetMaskAndExpect(bitstring);
- const auto [arg_masks, arg_shifts] = GetArgInfo<args_count>(bitstring);
+ const auto [mask, expect] = mask_and_expect;
+ const auto [arg_masks, arg_shifts] = masks_and_shifts;
const auto proxy_fn = VisitorCaller<FnT>::Make(Iota(), fn, arg_masks, arg_shifts);
return MatcherT(name, mask, expect, proxy_fn);
}
};
+#define DYNARMIC_DECODER_GET_MATCHER(MatcherT, fn, name, bitstring) Decoder::detail::detail<MatcherT<V>>::GetMatcher(&V::fn, name, Decoder::detail::detail<MatcherT<V>>::GetMaskAndExpect(bitstring), Decoder::detail::detail<MatcherT<V>>::template GetArgInfo<mp::parameter_count_v<decltype(&V::fn)>>(bitstring))
+
} // namespace detail
} // namespace Dynarmic::Decoder