Use standard binary multiple unit symbols for game size display.

Use integer math for the calculation as we cannot rely on floats for something as important as game size display!

Source/Core/Common/Src/MathUtil.h

@@ -152,6 +152,28 @@ float MathFloatVectorSum(const std::vector<float>&);
 #define ROUND_UP(x, a)		(((x) + (a) - 1) & ~((a) - 1))
 #define ROUND_DOWN(x, a)	((x) & ~((a) - 1))
 
+template <typename T>
+T Log2(T val)
+{
+#if defined(_M_X64)
+	T result;
+	asm
+	(
+		"bsr %1, %0"
+		: "=r"(result)
+		: "r"(val)
+	);
+	return result;
+#else
+	T result = -1;
+	while (val != 0)
+	{
+		val >>= 1;
+		++result;
+	}
+	return result;
+#endif
+}
 
 // Tiny matrix/vector library.
 // Used for things like Free-Look in the gfx backend.

Source/Core/DolphinWX/Src/GameListCtrl.cpp

@@ -35,6 +35,7 @@
 #include "CDUtils.h"
 #include "WxUtils.h"
 #include "Main.h"
+#include "MathUtil.h"
 
 #include "../resources/Flag_Europe.xpm"
 #include "../resources/Flag_Germany.xpm"
@@ -380,26 +381,18 @@ void CGameListCtrl::Update()
 	SetFocus();
 }
 
-wxString NiceSizeFormat(s64 _size)
+wxString NiceSizeFormat(u64 _size)
 {
-	const char* sizes[] = {"b", "KB", "MB", "GB", "TB", "PB", "EB"};
+	const char* const unit_symbols[] = {"B", "KiB", "MiB", "GiB", "TiB", "PiB", "EiB", "ZiB", "YiB"};
-	int s = 0;
+	
-	int frac = 0;
+	auto const unit = Log2(std::max<u64>(_size, 1)) / 10;
+	auto const unit_size = (1 << (unit * 10));
+	
+	// ugly rounding integer math
+	auto const value = (_size + unit_size / 2) / unit_size;
+	auto const frac = (_size % unit_size * 10 + unit_size / 2) / unit_size % 10;
 
-	while (_size > (s64)1024)
+	return StrToWxStr(StringFromFormat("%llu.%llu %s", value, frac, unit_symbols[unit]));
-	{
-		s++;
-		frac   = (int)_size & 1023;
-		_size /= (s64)1024;
-	}
-
-	float f = (float)_size + ((float)frac / 1024.0f);
-
-	wxString NiceString;
-	char tempstr[32];
-	sprintf(tempstr,"%3.1f %s", f, sizes[s]);
-	NiceString = StrToWxStr(tempstr);
-	return(NiceString);
 }
 
 void CGameListCtrl::InsertItemInReportView(long _Index)