Time Stamp Counter - Wikipedia
WEBThe Time Stamp Counter ( TSC) is a 64-bit register present on all x86 processors since the Pentium. It counts the number of CPU cycles since its reset. The instruction RDTSC returns the TSC in EDX:EAX. In x86-64 mode, RDTSC also clears the upper 32 bits of RAX and RDX. Its opcode is 0F 31. [1]
A bit detailed info on Intel Time Stamp Counter (TSC)
WEBSep 1, 2020 · The RDTSC instruction reads the time-stamp counter and is guaranteed to return a monotonically increasing unique value whenever executed, except for a 64-bit counter wraparound. Intel...
How to count clock cycles with RDTSC in GCC x86?
WEB# MSVC 19 2017 -Ox unsigned __int64 time_something(void) PROC ; time_something rdtsc shl rdx, 32 ; high <<= 32 or rax, rdx mov rcx, rax ; missed optimization: lea rcx, [rdx+rax] ; rcx = start ;; timed region (empty) rdtsc shl rdx, 32 or rax, rdx ; rax = end sub rax, rcx ; end -= start ret 0 unsigned __int64 time_something(void) ENDP ; time ...
WEBOne work-around for this problem is to use "emit" statements at the top of the file, as shown below: #define rdtsc __asm __emit 0fh __asm __emit 031h #define cpuid __asm __emit 0fh __asm __emit 0a2h This will replace all occurrences of RDTSC and CPUID with their corresponding opcodes in the compiled ".obj" file.
RDTSC — Read Time-Stamp Counter - felixcloutier.com
WEBDescription ¶. Reads the current value of the processor’s time-stamp counter (a 64-bit MSR) into the EDX:EAX registers. The EDX register is loaded with the high-order 32 bits of the MSR and the EAX register is loaded with the low-order 32 bits. (On processors that support the Intel 64 architecture, the high-order 32 bits of each of RAX and ...
Measure the execution time using RDTSC - Intel Communities
WEBMar 3, 2022 · 2,980 Views. Solved Jump to solution. Hi. I have been trying to use RDTSC and RDTSCP to measure the execution time of some code under test. I found the article “How to Benchmark Code Execution Times on Intel® IA-32 and IA-64 Instruction Set Architectures”, September 2010 ( …
RDTSC—Read Time-Stamp Counter - GitHub Pages
WEBDescription. Reads the current value of the processor’s time-stamp counter (a 64-bit MSR) into the EDX:EAX registers. The EDX register is loaded with the high-order 32 bits of the MSR and the EAX register is loaded with the low-order 32 bits. (On processors that support the Intel 64 architecture, the high-order 32 bits of each of RAX and RDX ...
Rdtsc - Assembly Language Reference
WEBSee “Time Stamp Counter” in Chapter 18 of the Intel ® 64 and IA-32 Architectures Software Developer’s Manual, Volume 3B, for specific details of the time stamp counter behavior. The time stamp disable (TSD) flag in register CR4 restricts the use of the RDTSC instruction as follows.
Intel Pentium Instruction Set Reference - RDTSC - Read Time …
WEBLoads the current value of the processor's time-stamp counter into the EDX:EAX registers. The time-stamp counter is contained in a 64-bit MSR. The high-order 32 bits of the MSR are loaded into the EDX register, and the low-order 32 bits are loaded into the EAX register.
RDTSC | x86 Instruction Set Reference
WEBApr 18, 2019 · Description. Loads the current value of the processor's time-stamp counter into the EDX:EAX registers. The time-stamp counter is contained in a 64-bit MSR. The high-order 32 bits of the MSR are loaded into the EDX register, and the low-order 32 bits are loaded into the EAX register.
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