From 7c970132b5dd6eaa40f114355e0125091ceb8142 Mon Sep 17 00:00:00 2001
From: David <25727384+ogniK5377@users.noreply.github.com>
Date: Tue, 30 Jun 2020 15:32:24 +1000
Subject: [PATCH] macro: Add support for "middle methods" on the code cache
 (#4112)

Macro code is just uploaded sequentially from a starting address, however that does not mean the entry point for the macro is at that address. This PR adds preliminary support for executing macros in the middle of our cached code.
---
 src/video_core/macro/macro.cpp | 35 ++++++++++++++++++++++++++--------
 1 file changed, 27 insertions(+), 8 deletions(-)

diff --git a/src/video_core/macro/macro.cpp b/src/video_core/macro/macro.cpp
index ef7dad349e..a50e7b4e0b 100644
--- a/src/video_core/macro/macro.cpp
+++ b/src/video_core/macro/macro.cpp
@@ -2,6 +2,7 @@
 // Licensed under GPLv2 or any later version
 // Refer to the license.txt file included.
 
+#include <optional>
 #include <boost/container_hash/hash.hpp>
 #include "common/assert.h"
 #include "common/logging/log.h"
@@ -35,22 +36,40 @@ void MacroEngine::Execute(Engines::Maxwell3D& maxwell3d, u32 method,
         }
     } else {
         // Macro not compiled, check if it's uploaded and if so, compile it
-        auto macro_code = uploaded_macro_code.find(method);
+        std::optional<u32> mid_method = std::nullopt;
+        const auto macro_code = uploaded_macro_code.find(method);
         if (macro_code == uploaded_macro_code.end()) {
-            UNREACHABLE_MSG("Macro 0x{0:x} was not uploaded", method);
-            return;
+            for (const auto& [method_base, code] : uploaded_macro_code) {
+                if (method >= method_base && (method - method_base) < code.size()) {
+                    mid_method = method_base;
+                    break;
+                }
+            }
+            if (!mid_method.has_value()) {
+                UNREACHABLE_MSG("Macro 0x{0:x} was not uploaded", method);
+                return;
+            }
         }
         auto& cache_info = macro_cache[method];
-        cache_info.hash = boost::hash_value(macro_code->second);
-        cache_info.lle_program = Compile(macro_code->second);
+
+        if (!mid_method.has_value()) {
+            cache_info.lle_program = Compile(macro_code->second);
+            cache_info.hash = boost::hash_value(macro_code->second);
+        } else {
+            const auto& macro_cached = uploaded_macro_code[mid_method.value()];
+            const auto rebased_method = method - mid_method.value();
+            auto& code = uploaded_macro_code[method];
+            code.resize(macro_cached.size() - rebased_method);
+            std::memcpy(code.data(), macro_cached.data() + rebased_method,
+                        code.size() * sizeof(u32));
+            cache_info.hash = boost::hash_value(code);
+            cache_info.lle_program = Compile(code);
+        }
 
         auto hle_program = hle_macros->GetHLEProgram(cache_info.hash);
         if (hle_program.has_value()) {
             cache_info.has_hle_program = true;
             cache_info.hle_program = std::move(hle_program.value());
-        }
-
-        if (cache_info.has_hle_program) {
             cache_info.hle_program->Execute(parameters, method);
         } else {
             cache_info.lle_program->Execute(parameters, method);