fp: Implement FPProcessNaN

src/CMakeLists.txt

@@ -24,6 +24,8 @@ add_library(dynarmic
     common/fp/op/FPToFixed.h
     common/fp/process_exception.cpp
     common/fp/process_exception.h
+    common/fp/process_nan.cpp
+    common/fp/process_nan.h
     common/fp/rounding_mode.h
     common/fp/unpacked.cpp
     common/fp/unpacked.h

src/common/fp/process_nan.cpp

@@ -0,0 +1,40 @@
+/* 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 "common/assert.h"
+#include "common/bit_util.h"
+#include "common/fp/fpsr.h"
+#include "common/fp/info.h"
+#include "common/fp/process_exception.h"
+#include "common/fp/process_nan.h"
+#include "frontend/A64/FPCR.h"
+
+namespace Dynarmic::FP {
+
+template<typename FPT>
+FPT FPProcessNaN(FPType type, FPT op, FPCR fpcr, FPSR& fpsr) {
+    ASSERT(type == FPType::QNaN || type == FPType::SNaN);
+
+    constexpr size_t topfrac = FPInfo<FPT>::explicit_mantissa_width - 1;
+
+    FPT result = op;
+
+    if (type == FPType::SNaN) {
+        result = Common::ModifyBit<topfrac>(op, true);
+        FPProcessException(FPExc::InvalidOp, fpcr, fpsr);
+    }
+
+    if (fpcr.DN()) {
+        result = FPInfo<FPT>::DefaultNaN();
+    }
+
+    return result;
+}
+
+template u32 FPProcessNaN<u32>(FPType type, u32 op, FPCR fpcr, FPSR& fpsr);
+template u64 FPProcessNaN<u64>(FPType type, u64 op, FPCR fpcr, FPSR& fpsr);
+
+} // namespace Dynarmic::FP 

src/common/fp/process_nan.h

@@ -0,0 +1,20 @@
+/* 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.
+ */
+
+#pragma once
+
+#include "common/fp/fpsr.h"
+#include "common/fp/unpacked.h"
+#include "frontend/A64/FPCR.h"
+
+namespace Dynarmic::FP {
+
+using FPCR = A64::FPCR;
+
+template<typename FPT>
+FPT FPProcessNaN(FPType type, FPT op, FPCR fpcr, FPSR& fpsr);
+
+} // namespace Dynarmic::FP