ir_opt: Port a32_merge_interpreter_blocks

src/CMakeLists.txt

@@ -156,6 +156,7 @@ if ("A32" IN_LIST DYNARMIC_FRONTENDS)
         frontend/A32/translate/translate_thumb.cpp
         ir_opt/a32_constant_memory_reads_pass.cpp
         ir_opt/a32_get_set_elimination_pass.cpp
+        ir_opt/a32_merge_interpret_blocks.cpp
     )
 endif()
 

src/ir_opt/a32_merge_interpret_blocks.cpp

@@ -0,0 +1,56 @@
+/* This file is part of the dynarmic project.
+ * Copyright (c) 2018 MerryMage
+ * This software may be used and distributed according to the terms of the GNU
+ * General Public License version 2 or any later version.
+ */
+
+#include <array>
+
+#include <boost/variant/get.hpp>
+
+#include "common/assert.h"
+#include "common/common_types.h"
+#include "dynarmic/A32/config.h"
+#include "frontend/A32/location_descriptor.h"
+#include "frontend/A32/translate/translate.h"
+#include "frontend/ir/basic_block.h"
+#include "ir_opt/passes.h"
+
+namespace Dynarmic::Optimization {
+
+void A32MergeInterpretBlocksPass(IR::Block& block, A32::UserCallbacks* cb) {
+    const auto is_interpret_instruction = [cb](A32::LocationDescriptor location) {
+        const u32 instruction = cb->MemoryReadCode(location.PC());
+
+        IR::Block new_block{location};
+        A32::TranslateSingleInstruction(new_block, location, instruction);
+
+        if (!new_block.Instructions().empty())
+            return false;
+
+        const IR::Terminal terminal = new_block.GetTerminal();
+        if (auto term = boost::get<IR::Term::Interpret>(&terminal)) {
+            return term->next == location;
+        }
+
+        return false;
+    };
+
+    IR::Terminal terminal = block.GetTerminal();
+    auto term = boost::get<IR::Term::Interpret>(&terminal);
+    if (!term)
+        return;
+
+    A32::LocationDescriptor location{term->next};
+    size_t num_instructions = 1;
+
+    while (is_interpret_instruction(location.AdvancePC(static_cast<int>(num_instructions * 4)))) {
+        num_instructions++;
+    }
+
+    term->num_instructions = num_instructions;
+    block.ReplaceTerminal(terminal);
+    block.CycleCount() += num_instructions - 1;
+}
+
+} // namespace Dynarmic::Optimization

src/ir_opt/passes.h

@@ -22,6 +22,7 @@ namespace Dynarmic::Optimization {
 
 void A32ConstantMemoryReads(IR::Block& block, A32::UserCallbacks* cb);
 void A32GetSetElimination(IR::Block& block);
+void A32MergeInterpretBlocksPass(IR::Block& block, A32::UserCallbacks* cb);
 void A64CallbackConfigPass(IR::Block& block, const A64::UserConfig& conf);
 void A64GetSetElimination(IR::Block& block);
 void A64MergeInterpretBlocksPass(IR::Block& block, A64::UserCallbacks* cb);