Move all core types into namespaces (#1886)

* Reorganize namespaces

- Most types are now moved into the `melonDS` namespace
- Only good chance to do this for a while, since a big refactor is next

* Fix the build

src/dolphin/Arm64Emitter.h

@@ -14,6 +14,8 @@
 
 namespace Arm64Gen
 {
+using namespace melonDS;
+using namespace Common;
 // X30 serves a dual purpose as a link register
 // Encoded as <u3:type><u5:reg>
 // Types:

src/dolphin/ArmCommon.h

@@ -24,4 +24,4 @@ enum CCFlags
   CC_HS = CC_CS,  // Alias of CC_CS  Unsigned higher or same
   CC_LO = CC_CC,  // Alias of CC_CC  Unsigned lower
 };
-const u32 NO_COND = 0xE0000000;
+const melonDS::u32 NO_COND = 0xE0000000;

src/dolphin/BitSet.h

@@ -10,6 +10,7 @@
 
 namespace Common
 {
+using namespace melonDS;
 #if defined(__GNUC__) || defined(__clang__)
 __attribute((always_inline)) static constexpr int CountSetBits(u8 val)
 {
@@ -218,9 +219,10 @@ public:
   constexpr Iterator end() const { return Iterator(m_val, -1); }
   IntTy m_val;
 };
+
+using BitSet8 = BitSet<u8>;
+using BitSet16 = BitSet<u16>;
+using BitSet32 = BitSet<u32>;
+using BitSet64 = BitSet<u64>;
 }  // namespace Common
 
-using BitSet8 = Common::BitSet<u8>;
-using BitSet16 = Common::BitSet<u16>;
-using BitSet32 = Common::BitSet<u32>;
-using BitSet64 = Common::BitSet<u64>;

src/dolphin/MathUtil.h

@@ -38,7 +38,7 @@ constexpr bool IsPow2(T imm)
   return imm > 0 && (imm & (imm - 1)) == 0;
 }
 
-constexpr u32 NextPowerOf2(u32 value)
+constexpr melonDS::u32 NextPowerOf2(melonDS::u32 value)
 {
   --value;
   value |= value >> 1;
@@ -99,7 +99,7 @@ struct Rectangle
 float MathFloatVectorSum(const std::vector<float>&);
 
 // Rounds down. 0 -> undefined
-inline int IntLog2(u64 val)
+inline int IntLog2(melonDS::u64 val)
 {
 #if defined(__GNUC__)
   return 63 - __builtin_clzll(val);

src/dolphin/x64ABI.cpp

@@ -6,8 +6,9 @@
 #include "x64ABI.h"
 #include "x64Emitter.h"
 
-using namespace Gen;
-
+namespace Gen
+{
+using namespace Common;
 // Shared code between Win64 and Unix64
 
 void XEmitter::ABI_CalculateFrameSize(BitSet32 mask, size_t rsp_alignment, size_t needed_frame_size,
@@ -117,3 +118,4 @@ void XEmitter::MOVTwo(int bits, Gen::X64Reg dst1, Gen::X64Reg src1, s32 offset1,
       ADD(bits, R(dst1), Imm32(offset1));
   }
 }
+}

src/dolphin/x64CPUDetect.cpp

@@ -17,6 +17,8 @@
 #include <sys/types.h>
 #endif
 
+using namespace melonDS;
+
 static inline void __cpuidex(int info[4], int function_id, int subfunction_id)
 {
 #ifdef __FreeBSD__

src/dolphin/x64Emitter.cpp

@@ -12,6 +12,8 @@
 #include "Compat.h"
 #include "CommonFuncs.h"
 
+using namespace melonDS;
+
 namespace Gen
 {
 // TODO(ector): Add EAX special casing, for ever so slightly smaller code.

src/dolphin/x64Emitter.h

@@ -19,6 +19,8 @@
 
 namespace Gen
 {
+using namespace melonDS;
+using namespace Common;
 enum CCFlags
 {
   CC_O = 0,