There is in fact a limitation at JavaScript/ECMAScript level of precision to 53-bit for integers (they are stored in the mantissa of a “double-like” 8 bytes memory buffer). So transmitting big numbers as JSON won’t be unserialized as expected by the JavaScript client, which would truncate them to its 53-bit resolution. > parseInt(“10765432100123456789”) 10765432100123458000 See … Read more
You need to use a version of the cl.exe compiler which emits x64 code. Which one depends a bit on your setup. Let’s consider the case you’re on a 64 bit machine. For this you’ll need to use the compiler which lives at c:\Program Files (x86)\Microsoft visual Studio 10.0\VC\bin\amd64\cl.exe If you’re on a 32 bit … Read more
If you want to use 32-bit references, your heap is limited to 32 GB. However, if you are willing to use 64-bit references, the size is likely to be limited by your OS, just as it is with 32-bit JVM. e.g. on Windows 32-bit this is 1.2 to 1.5 GB. Note: you will want your … Read more
Visual C++ does not support inline assembly for x64 (or ARM) processors, because generally using inline assembly is a bad idea. Usually compilers produce better assembly than humans. Even if you can produce better assembly than the compiler, using inline assembly generally defeats code optimizers of any type. Sure, your bit of hand optimized code … Read more
No, a 64-bit process can only load 64-bit DLLs and a 32-bit process can only load 32-bit DLLs. What you’re probably thinking of is that a 64-bit operating system can run 32-bit processes. The main issue with .NET is that – prior to VS2010 – executable projects defaulted to “AnyCPU” which means it would load … Read more
The high order bits are reserved in case the address bus would be increased in the future, so you can’t use it simply like that The AMD64 architecture defines a 64-bit virtual address format, of which the low-order 48 bits are used in current implementations (…) The architecture definition allows this limit to be raised … Read more
No, the sizeof(int) is implementation defined, and is usually 4 bytes. On the other hand, in order to address more than 4GB of memory (that 32bit systems can do), you need your pointers to be 8 bytes wide. int* just holds the address to “somewhere in memory”, and you can’t address more than 4GB of … Read more
I do it like this win32 { ## Windows common build here !contains(QMAKE_TARGET.arch, x86_64) { message(“x86 build”) ## Windows x86 (32bit) specific build here } else { message(“x86_64 build”) ## Windows x64 (64bit) specific build here } }
We do something similar to build core assemblies for .NET Compact Framework. Try this: <Target Name=”AfterBuild”> <MSBuild Condition=” ‘$(Platform)’ == ‘x86’ ” Projects=”$(MSBuildProjectFile)” Properties=”Platform=x64;PlatFormTarget=x64″ RunEachTargetSeparately=”true” /> </Target>
There’s a great article on Wikipedia about the differences and benefits of 64bit Intel/AMD cpus over their 32 bit versions. It should have all the information you need. Some on the key differences are: 16 general purpose registers instead of 8 Additional SSE registers A no execute (NX) bit to prevent buffer overrun attacks