每周期运行ARM Cortex CPU?

时间:2015-02-20 18:06:26

标签: arm cpu hardware

我需要ARM处理器可以执行的每个周期的操作数,特别是Cortex-A7,Cortex-A9和Cortex-A15的操作数。 我在网上找不到任何东西!

谢谢

编辑:我需要它来计算理论峰值性能。

2 个答案:

答案 0 :(得分:4)

I have not looked into integers yet but for single and double floating operations per cycle this is what I have come up with so far (from flops-per-cycle-for-sandy-bridge-and-haswell-sse2-avx-avx2, peak-flops-per-cycle-for-arm11-and-cortex-a7-cores-in-raspberry-pi-1-and-2, and Cortex-A9 NEON Media Processing Engine Technical Reference Manual).

Cortex-A7:

  • 0.5 DP FLOPs/cycle: scalar VMLA.F64 every four cycles.
  • 1.0 DP FLOPs/cycle: scalar VADD.F64 every cycle.
  • 2.0 SP FLOPs/cycle: scalar VMLA.F32 every cycle.
  • 2.0 SP FLOPs/cycle: 2-wide VMLA.F32 every other cycle.

Cortex-A9:

  • 1.5 DP FLOPs/cycle: scalar VMLA.F64 + scalar VADD.F64 every other cycle.
  • 4.0 SP FLOPs/cycle: 2-wide VMLA.F32 every cycle.

Cortex-A15:

  • 2.0 DP FLOPs/cycle: scalar VMLA.F64 (or VFMA.F64) every cycle.
  • 8.0 SP FLOPs/cycle: 4-wide VMLA.F32 (or VFMA.F32) every cycle.

One interesting observation is that Neon floating point no faster than VFP for the Cortex-A7.

答案 1 :(得分:0)