cpu-architecture

问题 All of a sudden Xcode threw me this error at compilation time: Undefined symbols for architecture x86_64: "_OBJC_CLASS_$_Format", referenced from: objc-class-ref in WOExerciseListViewController.o ld: symbol(s) not found for architecture x86_64 clang: error: linker command failed with exit code 1 (use -v to see invocation) After doing some research, I may understand that a library I'm using is not compatible with 64 bit version. But this is very strange since I've been working with the same

问题 All of a sudden Xcode threw me this error at compilation time: Undefined symbols for architecture x86_64: "_OBJC_CLASS_$_Format", referenced from: objc-class-ref in WOExerciseListViewController.o ld: symbol(s) not found for architecture x86_64 clang: error: linker command failed with exit code 1 (use -v to see invocation) After doing some research, I may understand that a library I'm using is not compatible with 64 bit version. But this is very strange since I've been working with the same

问题 It's my first time doing MIPS assembly and I'm trying to create a program that (1) accepts user's input (2) pre-store it in a specific address (3) multiply using repeated addition Here's my program: #Data Segment# .data 0x10010000 x: .word 1988 y: .word 1923 .text #Main Segment main: sub $t3, $t3, $t3 #initialize counter sub $t4, $t4, $t4 #initialize product multiloop: lui $t0, 0x1001 lw $t1, 0($t0) #load first integer value; variable for addition lw $t2, 4($t0) #load second integer value;

问题 I'm compiling data to compare CPU and GPU GFLOP performance, and I'm looking currently at dual socket CPUs (E5-26xx family), however after Broadwell comes Skylake architecture which has Bronze and Silver dual processor families, but they have half the cores and performance than the Broadwell ones. Am I missing something? 回答1: Interesting, it seems you're right that the only high-core-count Skylake-server chips are also capable of being used in 4-socket systems. (https://en.wikichip.org/wiki

问题 I found in the net something about jump instruction (j, jr, jal): Always use a delay slot (A noop on the next offset) when using Jump commands Is it correct? I can't understand why should i use noop after jump. Source 来源： https://stackoverflow.com/questions/47423368/mips-jump-instruction-delay-slot

问题 just a simple question regarding calculations in IJVM as I couldn't find the solution in their documentation. Suppose we need to perform the following calculation: BIPUSH 0x32 // PUSH 2 BIPUSH 0x33 // PUSH 3 IADD // PUSH sum(2,3) OUT // output: "e" IADD ----> Pop two words from stack; push their sum I know the solution is likely straight forward, but for the life of me I can't recall on how to convert the addition/output to the actual digits. How to make it output "5" instead of this stupid

问题 Is it simpler to prevent buffer overflows explorations with two stacks in general? One stack for variables and passing arguments, the other for return addresses. Or things like NX/XD-bits (on AMD/Intel x86) as non-executable stack do it better? 回答1: Itanium has two stacks. I believe one is for storing local variables (like arrays and stuff), while the other is for return addresses. This way, you can't overwrite return addresses by overrunning a buffer. https://blogs.msdn.microsoft.com

问题 I know it's possible to run Java workbenches on Gem5 (http://www.gem5.org/Main_Page) simulator for ARM architecture. I want to run a simulation of a Java application on ISA x86, is this possible? Thanks for helping me. 来源： https://stackoverflow.com/questions/52045994/is-it-possible-to-run-java-jar-on-gem5-simulator-with-isa-x86

问题 If we consider an hierarchical single level write back cache with write allocate policy , then the formula for average access time during write operation is given by :- Twrite = (H)(Tc) + (1-H)(Tc + Tm + (x*Tm)). Where, H= hit ratio of cache. Tc=access time of cache. Tm= access time of memory. x= fraction of cache blocks which are dirty. The above formula is given in this site https://gateoverflow.in/14480/formula-write-back-write-through-access-time-parallel-serial?show=14502#a14502 However,

问题 If a CPU core uses a write buffer, then the load can bypass the most recent store to the referenced location from the write buffer, without waiting until it will appear in the cache. But, as it's written in A Primer on Memory Consistency and Coherence, if the CPU honors TSO memory model, then ... multithreading introduces a subtle write buffer issue for TSO. TSO write buffers are logically private to each thread context (virtual core). Thus, on a multithreaded core, one thread context should