subr.l |
pilAsm
# (car 'var) -> any
(code 'doCar 2)
push X #push whatever value was here onto the stack
ld X E #load pointer to expression E, into X
ld E ((E CDR)) # Get arg #load the value
eval
num E # Need variable
jnz varErrEX
ld E (E) # Take CAR
pop X
ret
CPU Registers:
+---+---+---+---+---+---+---+---+
| A | B | \ [A]ccumulator
+---+---+---+---+---+---+---+---+ D [B]yte register
| C | / [C]ount register
+---+---+---+---+---+---+---+---+ [D]ouble register
| E | [E]xpression register
+---+---+---+---+---+---+---+---+
+---+---+---+---+---+---+---+---+
| X | [X] Index register
+---+---+---+---+---+---+---+---+ [Y] Index register
| Y | [Z] Index register
+---+---+---+---+---+---+---+---+
| Z |
+---+---+---+---+---+---+---+---+
+---+---+---+---+---+---+---+---+
| L | [L]ink register
+---+---+---+---+---+---+---+---+ [S]tack pointer
| S |
+---+---+---+---+---+---+---+---+
+-------------------------------+
| [z]ero [s]ign [x,b,c]arry | [F]lags
+-------------------------------+
http:///wiki/?cardocar
