shader_decode: Implement MOV_C and MOV_R

src/video_core/shader/decode/arithmetic.cpp

@@ -11,12 +11,34 @@ namespace VideoCommon::Shader {
 
 using Tegra::Shader::Instruction;
 using Tegra::Shader::OpCode;
+using Tegra::Shader::SubOp;
 
 u32 ShaderIR::DecodeArithmetic(BasicBlock& bb, u32 pc) {
     const Instruction instr = {program_code[pc]};
     const auto opcode = OpCode::Decode(instr);
 
-    UNIMPLEMENTED();
+    Node op_a = GetRegister(instr.gpr8);
+
+    Node op_b = [&]() -> Node {
+        if (instr.is_b_imm) {
+            return GetImmediate19(instr);
+        } else if (instr.is_b_gpr) {
+            return GetRegister(instr.gpr20);
+        } else {
+            return GetConstBuffer(instr.cbuf34.index, instr.cbuf34.offset);
+        }
+    }();
+
+    switch (opcode->get().GetId()) {
+    case OpCode::Id::MOV_C:
+    case OpCode::Id::MOV_R: {
+        // MOV does not have neither 'abs' nor 'neg' bits.
+        SetRegister(bb, instr.gpr0, op_b);
+        break;
+    }
+    default:
+        UNIMPLEMENTED_MSG("Unhandled arithmetic instruction: {}", opcode->get().GetName());
+    }
 
     return pc;
 }