From d875c08ebfee6ef1f5c0c3efe1ad47cf6fc024a5 Mon Sep 17 00:00:00 2001
From: MerryMage <MerryMage@users.noreply.github.com>
Date: Tue, 26 Jun 2018 15:10:44 +0100
Subject: [PATCH] fp: Extract common RoundingMode enum

---
 src/CMakeLists.txt               |  1 +
 src/backend_x64/a32_emit_x64.cpp |  2 +-
 src/backend_x64/a64_emit_x64.cpp |  2 +-
 src/common/fp/rounding_mode.h    | 30 ++++++++++++++++++++++++++++++
 src/frontend/A32/FPSCR.h         | 12 +++---------
 src/frontend/A64/FPCR.h          | 12 +++---------
 6 files changed, 39 insertions(+), 20 deletions(-)
 create mode 100644 src/common/fp/rounding_mode.h

diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 118f8799..df52f329 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -17,6 +17,7 @@ add_library(dynarmic
     common/crc32.cpp
     common/crc32.h
     common/fp_util.h
+    common/fp/rounding_mode.h
     common/intrusive_list.h
     common/iterator_util.h
     common/llvm_disassemble.cpp
diff --git a/src/backend_x64/a32_emit_x64.cpp b/src/backend_x64/a32_emit_x64.cpp
index 80ca023c..0fc0e290 100644
--- a/src/backend_x64/a32_emit_x64.cpp
+++ b/src/backend_x64/a32_emit_x64.cpp
@@ -59,7 +59,7 @@ A32::LocationDescriptor A32EmitContext::Location() const {
 }
 
 bool A32EmitContext::FPSCR_RoundTowardsZero() const {
-    return Location().FPSCR().RMode() != A32::FPSCR::RoundingMode::TowardsZero;
+    return Location().FPSCR().RMode() != FP::RoundingMode::TowardsZero;
 }
 
 bool A32EmitContext::FPSCR_FTZ() const {
diff --git a/src/backend_x64/a64_emit_x64.cpp b/src/backend_x64/a64_emit_x64.cpp
index 54c4163c..e5f8f22f 100644
--- a/src/backend_x64/a64_emit_x64.cpp
+++ b/src/backend_x64/a64_emit_x64.cpp
@@ -41,7 +41,7 @@ A64::LocationDescriptor A64EmitContext::Location() const {
 }
 
 bool A64EmitContext::FPSCR_RoundTowardsZero() const {
-    return Location().FPCR().RMode() != A64::FPCR::RoundingMode::TowardsZero;
+    return Location().FPCR().RMode() != FP::RoundingMode::TowardsZero;
 }
 
 bool A64EmitContext::FPSCR_FTZ() const {
diff --git a/src/common/fp/rounding_mode.h b/src/common/fp/rounding_mode.h
new file mode 100644
index 00000000..01ca790b
--- /dev/null
+++ b/src/common/fp/rounding_mode.h
@@ -0,0 +1,30 @@
+/* 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/common_types.h"
+
+namespace Dynarmic::FP {
+
+/// Ordering of first four values is important as they correspond to bits in FPCR.
+enum class RoundingMode {
+    /// Round to nearest floating point. If there is a tie, round to nearest even digit in required position.
+    ToNearest_TieEven,
+    /// Round up towards positive infinity.
+    TowardsPlusInfinity,
+    /// Round downwards towards negative infinity.
+    TowardsMinusInfinity,
+    /// Truncate towards zero.
+    TowardsZero,
+    /// Round to nearest floating point. If there is a tie, round away from zero.
+    ToNearest_TieAwayFromZero,
+    /// Von Neumann rounding (as modified by Brent). Also known as sticky rounding.
+    /// Set the least significant bit to 1 if the result is not exact.
+    ToOdd,
+};
+
+} // namespace Dynarmic::FP
diff --git a/src/frontend/A32/FPSCR.h b/src/frontend/A32/FPSCR.h
index 51eb40f7..1cafbddb 100644
--- a/src/frontend/A32/FPSCR.h
+++ b/src/frontend/A32/FPSCR.h
@@ -10,6 +10,7 @@
 
 #include "common/bit_util.h"
 #include "common/common_types.h"
+#include "common/fp/rounding_mode.h"
 
 namespace Dynarmic::A32 {
 
@@ -19,13 +20,6 @@ namespace Dynarmic::A32 {
 class FPSCR final
 {
 public:
-    enum class RoundingMode {
-        ToNearest,
-        TowardsPlusInfinity,
-        TowardsMinusInfinity,
-        TowardsZero
-    };
-
     FPSCR() = default;
     FPSCR(const FPSCR&) = default;
     FPSCR(FPSCR&&) = default;
@@ -79,8 +73,8 @@ public:
     }
 
     /// Rounding mode control field.
-    RoundingMode RMode() const {
-        return static_cast<RoundingMode>(Common::Bits<22, 23>(value));
+    FP::RoundingMode RMode() const {
+        return static_cast<FP::RoundingMode>(Common::Bits<22, 23>(value));
     }
 
     /// Indicates the stride of a vector.
diff --git a/src/frontend/A64/FPCR.h b/src/frontend/A64/FPCR.h
index 5c1c524f..9e82733e 100644
--- a/src/frontend/A64/FPCR.h
+++ b/src/frontend/A64/FPCR.h
@@ -10,6 +10,7 @@
 
 #include "common/bit_util.h"
 #include "common/common_types.h"
+#include "common/fp/rounding_mode.h"
 
 namespace Dynarmic::A64 {
 
@@ -19,13 +20,6 @@ namespace Dynarmic::A64 {
 class FPCR final
 {
 public:
-    enum class RoundingMode {
-        ToNearest,
-        TowardsPlusInfinity,
-        TowardsMinusInfinity,
-        TowardsZero
-    };
-
     FPCR() = default;
     FPCR(const FPCR&) = default;
     FPCR(FPCR&&) = default;
@@ -54,8 +48,8 @@ public:
     }
 
     /// Rounding mode control field.
-    RoundingMode RMode() const {
-        return static_cast<RoundingMode>(Common::Bits<22, 23>(value));
+    FP::RoundingMode RMode() const {
+        return static_cast<FP::RoundingMode>(Common::Bits<22, 23>(value));
     }
 
     /// Input denormal exception trap enable flag.