x86-64

AFAIK x86-64 adds a number of general purpose registers to those derived from Intel x86 ( rax , rcx , etc), called r8 - r15 . Why did they name the new registers like this? Why not just follow existing naming convention and call them like rfx , rgx ... ? Numbering CPU registers is the norm, almost any processor does that. The 8086 processor however is ancient, they had an extremely limited transistor budget back in 1976. Implementing a 16-bit processor with only 20,000 active transistors was quite a tour-de-force. One way they cut down was by giving registers dedicated functions. At that point

I have some misunderstanding about cache lines. I'm using Haswell and Ubuntu . Now let's say we have 2-threaded application in which the following happens. mov [addr], dword 0xAC763F ;starting Thread 1 and Thread 2 Now let`s say the threads perform the following actions in parallel: Thread 1 Thread 2 mov rax, [addr] mov rax, [addr] mov [addr], dword 1 mov [addr], dword 2 Now in my understanding of what's going on is this: Before starting the main thread writes to the corresponding cache line ( addr ) and marks it as Exclusive . If both of the threads Thread 1 and Thread 2 finished reading

I am using native epoll transport in netty and was able to download netty-transport-native-epoll-4.0.32.jar from the repository. However I also need netty-transport-native-epoll-4.0.32.Final-linux-x86_64.jar but not unable to find it anywhere. Please let me know where to download this jar, or how to build it. The file can be found here : http://repo.scub-foundation.org/artifactory/libs-release/io/netty/netty-transport-native-epoll/4.0.32.Final/ The content doesn't seem to be different than from netty-all-4.0.32.Final.jar -> io\netty\channel\epoll\ 来源： https://stackoverflow.com/questions

(This question is specific to my machine's architecture and calling conventions, Windows x86_64) I don't exactly remember where I had read this, or if I had recalled it correctly, but I had heard that, when a function should return some struct or object by value, it will either stuff it in rax (if the object can fit in the register width of 64 bits) or be passed a pointer to where the resulting object would be (I'm guessing allocated in the calling function's stack frame) in rcx , where it would do all the usual initialization, and then a mov rax, rcx for the return trip. That is, something

Undefined symbols for architecture x86_64: "_BROADCAST_MODE_IBEACON", referenced from: -[MainViewController tableView:cellForRowAtIndexPath:] in MainViewController.o "_OBJC_CLASS_$_TZBeaconSDK", referenced from: objc-class-ref in MainViewController.o ld: symbol(s) not found for architecture x86_64 clang: error: linker command failed with exit code 1 (use -v to see invocation) I take that error when I want to use simulator. There is no problem when I build it on iPhone. There is only problem when I use simulator. I have tried to change Architectures from Build settings, error text changes as

I'm working on a research project that involves developing a new DVFS algorithm for Intel machines. To do this we're utilizing some of the code from the intel_pstates driver to actually determine the pstate for each individual CPU and using the wmsr function to set that value to registers (IA32_PERF_CTL). The problem we're encountering is when we run benchmarks, the CPU will randomly halt (not kernel panic or system hang). Is there a way we can setup a trace or another method to record the value that was trying to be written to the MSRs? 来源： https://stackoverflow.com/questions/47360483/how-to