shader_ir: Initial Decompile Setup

src/video_core/shader/ast.cpp

@@ -0,0 +1,180 @@
+// Copyright 2019 yuzu Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#include <string>
+
+#include "common/assert.h"
+#include "common/common_types.h"
+#include "video_core/shader/ast.h"
+#include "video_core/shader/expr.h"
+
+namespace VideoCommon::Shader {
+
+class ExprPrinter final {
+public:
+    ExprPrinter() = default;
+
+    void operator()(ExprAnd const& expr) {
+        inner += "( ";
+        std::visit(*this, *expr.operand1);
+        inner += " && ";
+        std::visit(*this, *expr.operand2);
+        inner += ')';
+    }
+
+    void operator()(ExprOr const& expr) {
+        inner += "( ";
+        std::visit(*this, *expr.operand1);
+        inner += " || ";
+        std::visit(*this, *expr.operand2);
+        inner += ')';
+    }
+
+    void operator()(ExprNot const& expr) {
+        inner += "!";
+        std::visit(*this, *expr.operand1);
+    }
+
+    void operator()(ExprPredicate const& expr) {
+        u32 pred = static_cast<u32>(expr.predicate);
+        if (pred > 7) {
+            inner += "!";
+            pred -= 8;
+        }
+        inner += "P" + std::to_string(pred);
+    }
+
+    void operator()(ExprCondCode const& expr) {
+        u32 cc = static_cast<u32>(expr.cc);
+        inner += "CC" + std::to_string(cc);
+    }
+
+    void operator()(ExprVar const& expr) {
+        inner += "V" + std::to_string(expr.var_index);
+    }
+
+    void operator()(ExprBoolean const& expr) {
+        inner += expr.value ? "true" : "false";
+    }
+
+    std::string& GetResult() {
+        return inner;
+    }
+
+    std::string inner{};
+};
+
+class ASTPrinter {
+public:
+    ASTPrinter() = default;
+
+    void operator()(ASTProgram& ast) {
+        scope++;
+        inner += "program {\n";
+        for (ASTNode& node : ast.nodes) {
+            Visit(node);
+        }
+        inner += "}\n";
+        scope--;
+    }
+
+    void operator()(ASTIf& ast) {
+        ExprPrinter expr_parser{};
+        std::visit(expr_parser, *ast.condition);
+        inner += Ident() + "if (" + expr_parser.GetResult() + ") {\n";
+        scope++;
+        for (auto& node : ast.then_nodes) {
+            Visit(node);
+        }
+        scope--;
+        if (ast.else_nodes.size() > 0) {
+            inner += Ident() + "} else {\n";
+            scope++;
+            for (auto& node : ast.else_nodes) {
+                Visit(node);
+            }
+            scope--;
+        } else {
+            inner += Ident() + "}\n";
+        }
+    }
+
+    void operator()(ASTBlockEncoded& ast) {
+        inner += Ident() + "Block(" + std::to_string(ast.start) + ", " + std::to_string(ast.end) +
+                 ");\n";
+    }
+
+    void operator()(ASTVarSet& ast) {
+        ExprPrinter expr_parser{};
+        std::visit(expr_parser, *ast.condition);
+        inner +=
+            Ident() + "V" + std::to_string(ast.index) + " := " + expr_parser.GetResult() + ";\n";
+    }
+
+    void operator()(ASTLabel& ast) {
+        inner += "Label_" + std::to_string(ast.index) + ":\n";
+    }
+
+    void operator()(ASTGoto& ast) {
+        ExprPrinter expr_parser{};
+        std::visit(expr_parser, *ast.condition);
+        inner += Ident() + "(" + expr_parser.GetResult() + ") -> goto Label_" +
+                 std::to_string(ast.label) + ";\n";
+    }
+
+    void operator()(ASTDoWhile& ast) {
+        ExprPrinter expr_parser{};
+        std::visit(expr_parser, *ast.condition);
+        inner += Ident() + "do {\n";
+        scope++;
+        for (auto& node : ast.loop_nodes) {
+            Visit(node);
+        }
+        scope--;
+        inner += Ident() + "} while (" + expr_parser.GetResult() + ")\n";
+    }
+
+    void operator()(ASTReturn& ast) {
+        ExprPrinter expr_parser{};
+        std::visit(expr_parser, *ast.condition);
+        inner += Ident() + "(" + expr_parser.GetResult() + ") -> " +
+                 (ast.kills ? "discard" : "exit") + ";\n";
+    }
+
+    std::string& Ident() {
+        if (memo_scope == scope) {
+            return tabs_memo;
+        }
+        tabs_memo = tabs.substr(0, scope * 2);
+        memo_scope = scope;
+        return tabs_memo;
+    }
+
+    void Visit(ASTNode& node) {
+        std::visit(*this, *node->GetInnerData());
+    }
+
+    std::string& GetResult() {
+        return inner;
+    }
+
+private:
+    std::string inner{};
+    u32 scope{};
+
+    std::string tabs_memo{};
+    u32 memo_scope{};
+
+    static std::string tabs;
+};
+
+std::string ASTPrinter::tabs = "                                    ";
+
+std::string ASTManager::Print() {
+    ASTPrinter printer{};
+    printer.Visit(main_node);
+    return printer.GetResult();
+}
+
+} // namespace VideoCommon::Shader