From f9079f9dce484ac025510e09d6cf09438d040240 Mon Sep 17 00:00:00 2001
From: wheremyfoodat <gponiris2004@gmail.com>
Date: Wed, 12 Oct 2022 00:28:50 +0300
Subject: [PATCH] [Shader interpreter] Implement CALL

---
 include/PICA/shader.hpp              |  2 ++
 src/core/PICA/shader_interpreter.cpp | 15 +++++++++++++++
 2 files changed, 17 insertions(+)

diff --git a/include/PICA/shader.hpp b/include/PICA/shader.hpp
index 847391f8..f282da72 100644
--- a/include/PICA/shader.hpp
+++ b/include/PICA/shader.hpp
@@ -22,6 +22,7 @@ namespace ShaderOpcodes {
 		MOV = 0x13,
 		NOP = 0x21,
 		END = 0x22,
+		CALL = 0x24,
 		CALLU = 0x26,
 		IFU = 0x27,
 		IFC = 0x28,
@@ -83,6 +84,7 @@ class PICAShader {
 
 	// Shader opcodes
 	void add(u32 instruction);
+	void call(u32 instruction);
 	void callu(u32 instruction);
 	void cmp(u32 instruction);
 	void dp3(u32 instruction);
diff --git a/src/core/PICA/shader_interpreter.cpp b/src/core/PICA/shader_interpreter.cpp
index 58be21d5..3931f033 100644
--- a/src/core/PICA/shader_interpreter.cpp
+++ b/src/core/PICA/shader_interpreter.cpp
@@ -13,6 +13,7 @@ void PICAShader::run() {
 
 		switch (opcode) {
 			case ShaderOpcodes::ADD: add(instruction); break;
+			case ShaderOpcodes::CALL: call(instruction); break;
 			case ShaderOpcodes::CALLU: callu(instruction); break;
 			case ShaderOpcodes::CMP1: case ShaderOpcodes::CMP2: 
 				cmp(instruction);
@@ -393,6 +394,20 @@ void PICAShader::ifu(u32 instruction) {
 	}
 }
 
+void PICAShader::call(u32 instruction) {
+	if (callIndex >= 4) [[unlikely]]
+		Helpers::panic("[PICA] Overflowed CALL stack");
+
+	const u32 num = instruction & 0xff;
+	const u32 dest = (instruction >> 10) & 0xfff;
+
+	auto& block = callInfo[callIndex++];
+	block.endingPC = dest + num;
+	block.returnPC = pc;
+
+	pc = dest;
+}
+
 void PICAShader::callu(u32 instruction) {
 	const u32 bit = (instruction >> 22) & 0xf; // Bit of the bool uniform to check