sforman
/
Thun
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

hmm...

This commit is contained in:
Simon Forman 2019-11-07 20:21:26 -08:00
parent 3f843ed4cc
commit 5172be7a0a
1 changed files with 44 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

44
thun/markII.rst
View File

@ -154,3 +154,47 @@ And write it to the (already decremented) sp.
ram[sp] = tos
cons
------------------------------
[グ,ケ,ゲ,ド,ゴ,サ],ヮ(cons),
グ pop(TEMP0, TOS) split_word(TEMP0, TOS), high_half_to(To, From), swap_halves(To, From), ror_imm(To, From, 16)
low_half(To) and_imm(Reg, Reg, 0xffff)
low_half(From) and_imm(Reg, Reg, 0xffff)
Puts the term on tos (the list to cons onto) into temp0 and points tos
deref(TOS) to the value under tos (the item to cons onto the list.)
ケ high_half(TEMP1, TOS) mov_imm_with_shift(0, 0xffff), Mask off the high half of (new) tos to isolate value.
and(TEMP1, TOS, 0)
ゲ or_inplace(TEMP0, TEMP1) ior(TEMP0, TEMP0, TEMP1) Combines value with the list in a new pair record.
ド write_cell(TEMP0, SP) add_imm(SP, SP, 4), Writes the new pair cell word to ++sp.
store_word(TEMP0, SP, 0)
ゴ low_half(TOS) and_imm(TOS, TOS, 0xffff) Delete the reference to second item down.
サ merge(SP, TOS) lsl_imm(0, SP, 16), Make a new pair record from the SP which points to the new cons'd list
ior(TOS, TOS, 0), and TOS which points to the rest of the stack. This record is then the
add_imm(SP, SP, 4) new TOS pair cell word, and we let the mainloop write it to RAM for us.
So now that i've recreated it, what is it doing?
⦾(グ, pop(TEMP0, TOS))
⦾(ケ, high_half(TEMP1, TOS))
⦾(ゲ, or_inplace(TEMP0, TEMP1))
⦾(ド, write_cell(TEMP0, SP))
⦾(ゴ, low_half(TOS))
⦾(サ, merge(SP, TOS))
⟐(pop(Reg, TOS)) --> ⟐([split_word(Reg, TOS), deref(TOS)]).
⟐(high_half(To, From)) --> [mov_imm_with_shift(0, 0xffff), and(To, From, 0)].
⟐(or_inplace(To, From)) --> [ior(To, To, From)].
⟐(write_cell(From, SP)) --> [add_imm(SP, SP, 4), store_word(From, SP, 0)].
⟐( low_half(Reg)) --> [and_imm(Reg, Reg, 0xffff)].
⟐(merge(SP, TOS)) -->
[lsl_imm(0, SP, 16),
ior(TOS, TOS, 0),
add_imm(SP, SP, 4)].
This blows, just write it in assembly already.