From 5688573b3de12ca5bc49a038d92319d7bea54726 Mon Sep 17 00:00:00 2001
From: kd-11 <karokidii@gmail.com>
Date: Mon, 8 Dec 2025 02:44:20 +0300
Subject: [PATCH] rsx/fp: Fix pre-branch epilogue emit

---
 rpcs3/Emu/RSX/Program/Assembler/FPToCFG.cpp   |  2 +
 .../RSX/Program/FragmentProgramDecompiler.cpp | 53 ++++++++++---------
 2 files changed, 31 insertions(+), 24 deletions(-)

diff --git a/rpcs3/Emu/RSX/Program/Assembler/FPToCFG.cpp b/rpcs3/Emu/RSX/Program/Assembler/FPToCFG.cpp
index 577252fd83..1f1e5b3678 100644
--- a/rpcs3/Emu/RSX/Program/Assembler/FPToCFG.cpp
+++ b/rpcs3/Emu/RSX/Program/Assembler/FPToCFG.cpp
@@ -139,6 +139,7 @@ namespace rsx::assembler
 					default:
 						// Missing an edge type?
 						rsx_log.error("CFG: Unexpected block exit. Report to developers.");
+						break;
 					}
 				}
 				else if (bb->pred.empty())
@@ -221,6 +222,7 @@ namespace rsx::assembler
 					ir_inst.length += 4;
 					pc++;
 				}
+				break;
 			}
 
 			pc++;
diff --git a/rpcs3/Emu/RSX/Program/FragmentProgramDecompiler.cpp b/rpcs3/Emu/RSX/Program/FragmentProgramDecompiler.cpp
index 589e677b25..94b92ce98e 100644
--- a/rpcs3/Emu/RSX/Program/FragmentProgramDecompiler.cpp
+++ b/rpcs3/Emu/RSX/Program/FragmentProgramDecompiler.cpp
@@ -1276,7 +1276,7 @@ std::string FragmentProgramDecompiler::Decompile()
 		// The RSX CFG is missing the output block. We inject a fake tail block that ingests the ROP outputs.
 		BasicBlock* rop_block = nullptr;
 		BasicBlock* tail_block = &graph.blocks.back();
-		if (tail_block->instructions.size() == 0)
+		if (tail_block->instructions.empty())
 		{
 			// Merge block. Use this directly
 			rop_block = tail_block;
@@ -1326,6 +1326,20 @@ std::string FragmentProgramDecompiler::Decompile()
 		block_data[block] = { level, loop };
 	};
 
+	auto emit_block = [&](const std::vector<Instruction>& instructions)
+	{
+		for (auto& inst : instructions)
+		{
+			m_instruction = &inst;
+			dst.HEX = inst.bytecode[0];
+			src0.HEX = inst.bytecode[1];
+			src1.HEX = inst.bytecode[2];
+			src2.HEX = inst.bytecode[3];
+
+			ensure(handle_tex_srb(inst.opcode) || handle_sct_scb(inst.opcode), "Unsupported operation");
+		}
+	};
+
 	for (const auto &block : graph.blocks)
 	{
 		auto found = block_data.find(&block);
@@ -1376,21 +1390,22 @@ std::string FragmentProgramDecompiler::Decompile()
 		if (!block.prologue.empty())
 		{
 			AddCode("// Prologue");
-
-			for (auto& inst : block.prologue)
-			{
-				m_instruction = &inst;
-				dst.HEX = inst.bytecode[0];
-				src0.HEX = inst.bytecode[1];
-				src1.HEX = inst.bytecode[2];
-				src2.HEX = inst.bytecode[3];
-
-				ensure(handle_tex_srb(inst.opcode) || handle_sct_scb(inst.opcode), "Unsupported operation");
-			}
+			emit_block(block.prologue);
 		}
 
+		const bool early_epilogue =
+			!block.epilogue.empty() &&
+			!block.succ.empty() &&
+			(block.succ.front().type == EdgeType::IF || block.succ.front().type == EdgeType::LOOP);
+
 		for (const auto& inst : block.instructions)
 		{
+			if (early_epilogue && &inst == &block.instructions.back())
+			{
+				AddCode("// Epilogue");
+				emit_block(block.epilogue);
+			}
+
 			m_instruction = &inst;
 
 			dst.HEX = inst.bytecode[0];
@@ -1459,20 +1474,10 @@ std::string FragmentProgramDecompiler::Decompile()
 			if (dst.end) break;
 		}
 
-		if (!block.epilogue.empty())
+		if (!early_epilogue && !block.epilogue.empty())
 		{
 			AddCode("// Epilogue");
-
-			for (auto& inst : block.epilogue)
-			{
-				m_instruction = &inst;
-				dst.HEX = inst.bytecode[0];
-				src0.HEX = inst.bytecode[1];
-				src1.HEX = inst.bytecode[2];
-				src2.HEX = inst.bytecode[3];
-
-				ensure(handle_tex_srb(inst.opcode) || handle_sct_scb(inst.opcode), "Unsupported operation");
-			}
+			emit_block(block.epilogue);
 		}
 
 		for (auto& succ : block.succ)