They said that they implemented x86 ISA memory handling instructions, that substantially sped up the emulation. I don't remember exactly which now, but they explained this all in a WWDC video about the emulation.
Intel customers required a second source supplier, i.e. IBM, thus, AMD was providing that for Intel in the beginning. Then later on AMD created the x86 64bit commands, which Intel adopted from AMD so now both share the same ISA.
Their math is incorrect.
The M1 scores about 300K in Coremarks and has 8 cores => 37.500 per core. M1 consumes about 12W => 1.5 W/core and thus: 37.500 ÷ 1.5 W/core = 25 K Coremarks per Watt.
But this company (or Andy Huang) is claiming M1 has 100 Coremarks per Watt!
Why don’t people check their math if it sounds far off?