early-access version 1255

2020-12-28 15:15:37 +00:00
parent 84b39492d1
commit 78b48028e1
6254 changed files with 1868140 additions and 0 deletions
--- a/externals/dynarmic/src/frontend/ir/terminal.h
+++ b/externals/dynarmic/src/frontend/ir/terminal.h
@@ -0,0 +1,126 @@
+/* This file is part of the dynarmic project.
+ * Copyright (c) 2016 MerryMage
+ * SPDX-License-Identifier: 0BSD
+ */
+
+#pragma once
+
+#include <boost/variant.hpp>
+
+#include "common/common_types.h"
+#include "frontend/ir/cond.h"
+#include "frontend/ir/location_descriptor.h"
+
+namespace Dynarmic::IR {
+namespace Term {
+
+struct Invalid {};
+
+/**
+ * This terminal instruction calls the interpreter, starting at `next`.
+ * The interpreter must interpret exactly `num_instructions` instructions.
+ */
+struct Interpret {
+    explicit Interpret(const LocationDescriptor& next_) : next(next_) {}
+    LocationDescriptor next; ///< Location at which interpretation starts.
+    size_t num_instructions = 1;
+};
+
+/**
+ * This terminal instruction returns control to the dispatcher.
+ * The dispatcher will use the current cpu state to determine what comes next.
+ */
+struct ReturnToDispatch {};
+
+/**
+ * This terminal instruction jumps to the basic block described by `next` if we have enough
+ * cycles remaining. If we do not have enough cycles remaining, we return to the
+ * dispatcher, which will return control to the host.
+ */
+struct LinkBlock {
+    explicit LinkBlock(const LocationDescriptor& next_) : next(next_) {}
+    LocationDescriptor next; ///< Location descriptor for next block.
+};
+
+/**
+ * This terminal instruction jumps to the basic block described by `next` unconditionally.
+ * This is an optimization and MUST only be emitted when this is guaranteed not to result
+ * in hanging, even in the face of other optimizations. (In practice, this means that only
+ * forward jumps to short-ish blocks would use this instruction.)
+ * A backend that doesn't support this optimization may choose to implement this exactly
+ * as LinkBlock.
+ */
+struct LinkBlockFast {
+    explicit LinkBlockFast(const LocationDescriptor& next_) : next(next_) {}
+    LocationDescriptor next; ///< Location descriptor for next block.
+};
+
+/**
+ * This terminal instruction checks the top of the Return Stack Buffer against the current
+ * location descriptor. If RSB lookup fails, control is returned to the dispatcher.
+ * This is an optimization for faster function calls. A backend that doesn't support
+ * this optimization or doesn't have a RSB may choose to implement this exactly as
+ * ReturnToDispatch.
+ */
+struct PopRSBHint {};
+
+/**
+ * This terminal instruction performs a lookup of the current location descriptor in the
+ * fast dispatch lookup table. A backend that doesn't support this optimization may choose
+ * to implement this exactly as ReturnToDispatch.
+ */
+struct FastDispatchHint {};
+
+struct If;
+struct CheckBit;
+struct CheckHalt;
+/// A Terminal is the terminal instruction in a MicroBlock.
+using Terminal = boost::variant<
+        Invalid,
+        Interpret,
+        ReturnToDispatch,
+        LinkBlock,
+        LinkBlockFast,
+        PopRSBHint,
+        FastDispatchHint,
+        boost::recursive_wrapper<If>,
+        boost::recursive_wrapper<CheckBit>,
+        boost::recursive_wrapper<CheckHalt>
+>;
+
+/**
+ * This terminal instruction conditionally executes one terminal or another depending
+ * on the run-time state of the ARM flags.
+ */
+struct If {
+    If(Cond if_, Terminal then_, Terminal else_) : if_(if_), then_(std::move(then_)), else_(std::move(else_)) {}
+    Cond if_;
+    Terminal then_;
+    Terminal else_;
+};
+
+/**
+ * This terminal instruction conditionally executes one terminal or another depending
+ * on the run-time state of the check bit.
+ * then_ is executed if the check bit is non-zero, otherwise else_ is executed.
+ */
+struct CheckBit {
+    CheckBit(Terminal then_, Terminal else_) : then_(std::move(then_)), else_(std::move(else_)) {}
+    Terminal then_;
+    Terminal else_;
+};
+
+/**
+ * This terminal instruction checks if a halt was requested. If it wasn't, else_ is
+ * executed.
+ */
+struct CheckHalt {
+    explicit CheckHalt(Terminal else_) : else_(std::move(else_)) {}
+    Terminal else_;
+};
+
+} // namespace Term
+
+using Term::Terminal;
+
+} // namespace Dynarmic::IR