From eb61ae37ae206cc19d682fb96853fd10ec1c6727 Mon Sep 17 00:00:00 2001
From: Eladash <elad3356p@gmail.com>
Date: Fri, 25 Aug 2023 19:39:19 +0300
Subject: [PATCH] rsx: Optimize RET returning to following CALL

---
 rpcs3/Emu/RSX/RSXFIFO.cpp | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/rpcs3/Emu/RSX/RSXFIFO.cpp b/rpcs3/Emu/RSX/RSXFIFO.cpp
index c4e52c6e6b..637db20913 100644
--- a/rpcs3/Emu/RSX/RSXFIFO.cpp
+++ b/rpcs3/Emu/RSX/RSXFIFO.cpp
@@ -701,6 +701,24 @@ namespace rsx
 					return;
 				}
 
+				// Optimize returning to another CALL
+				if ((ctrl->put & ~3) != fifo_ret_addr)
+				{
+					if (u32 addr = iomap_table.get_addr(fifo_ret_addr); addr != umax)
+					{
+						const u32 cmd0 = vm::read32(addr);
+
+						// Check for missing step flags, in case the user is single-stepping in the debugger
+						if ((cmd0 & RSX_METHOD_CALL_CMD_MASK) == RSX_METHOD_CALL_CMD && cpu_flag::dbg_step - state)
+						{
+							fifo_ctrl->set_get(cmd0 & RSX_METHOD_CALL_OFFSET_MASK);
+							last_known_code_start = ctrl->get;
+							fifo_ret_addr += 4;
+							return;
+						}
+					}
+				}
+
 				fifo_ctrl->set_get(std::exchange(fifo_ret_addr, RSX_CALL_STACK_EMPTY));
 				last_known_code_start = ctrl->get;
 				return;