The PIC16 is probably the closest - all arithmetic has to go through the W register. Confusingly PIC calls all internal memory "registers", but really it's more like a one-register machine.
The Z80 routes most arithmetic through its A (accumulator) register.
The inheritor of this is the X86, where there are much fewer register limitations but tradition and the lettering remain; (E)AX is the calling convention's first argument and return parameter. And the article itself details that you can get shorter opcodes by preferring to do arithmetic through EAX.
The Z80 routes most arithmetic through its A (accumulator) register.
The inheritor of this is the X86, where there are much fewer register limitations but tradition and the lettering remain; (E)AX is the calling convention's first argument and return parameter. And the article itself details that you can get shorter opcodes by preferring to do arithmetic through EAX.