Hyperthreading is an Intel technology really, as far as I'm aware, the FX8350 has a totally different architecture.
The quad core Intel chips with "Hyperthreading" may have 4 CPU cores with dual threads in each, hence why it shows as 8 threads.
The AMD FX8350 chips with "SMT" have 4 modules, each module technically has two CPU cores in it (integer cores), with some dedicated and some shared resources. So *technically* the FX8350 has 8 cores, though in Windows it is displayed as a 4 core, 8 thread processor.
Each "core" in the FX8350 chip also has a dedicated Level 1 cache, but shared Level 2 cache with it's other core in the same module.
This pic should give you an idea of how the FX architecture works:
If you take a look at a new Intel chip with quad core and hyperthreading, you'll see that each of the four cores has it's own dedicated Level 1 and 2 cache, but each core has dual threads so it appears as 8 logical cores.