#ifndef VVS_STDLIB_STACK
#define VVS_STDLIB_STACK

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@ Name:
@   stackrotate
@ Description:
@   Maximum rotation depth is 14. Stomps on heap[1]-heap[15].
@ Call Stack:
@   stack word n
@   ...
@   stack word 1
@   rotation depth (rd)  <-- TOS
@ Return Stack (n>rd=3):
@   stack word n
@   ...
@   stack word 1
@   stack word 3
@   stack word 2   <-- TOS
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
NSSVTSTSN               | Mark: 1010 (stackrotate)

@ For the convenience of other functions, modulo the
@ rotation depth by the available registers.
SSSTTTSN                | PUSH 14
TSTT                    | MODULO

@ Use heap[15] for generating register addresses.
SSSTTTTN                | PUSH 15 (ptr)
SSSSN                   | PUSH 0
TTS                     | STORE

@ Dump one word from stack to heap each pass through the loop.
NSSVSSSSTSTSSSSSSSSSN   | Mark: 00001010 00000000
SNT                     | SWAP
SSSTN                   | PUSH 1 (starting register)
SSSTTTTN                | PUSH 15 (ptr)
TTT                     | LOAD
TSSS                    | ADD
SNT                     | SWAP
TTS                     | STORE

@ See if the loop is complete.
SNS                     | DUP
SSSTTTTN                | PUSH 15 (ptr)
TTT                     | LOAD
SSSTN                   | PUSH 1
TSSS                    | ADD
TSST                    | SUBTRACT
NTSSSSSTSTSSSSSSSSTN    | BRZ > 00001010 00000001

@ Increment the loop counter
SSSTTTTN                | PUSH 15 (ptr)
TTT                     | LOAD
SSSTN                   | PUSH 1
TSSS                    | ADD
SSSTTTTN                | PUSH 15 (ptr)
SNT                     | SWAP
TTS                     | STORE
NSNSSSSTSTSSSSSSSSSN    | JMP > 00001010 00000000

@ The correct number of words have been stored to registers.
@ Time to read them back in rotated order.

@ First, prepare the counter in heap[15] again.
@ This consumes 'rd' from the stack.
NSSVSSSSTSTSSSSSSSSTN   | Mark: 00001010 00000001
SSSTN                   | PUSH 1
TSST                    | SUBTRACT
SSSTTTTN                | PUSH 15 (ptr)
SNT                     | SWAP
TTS                     | STORE

@ Second, read in the old TOS manually.
SSSTN                   | PUSH 1 (starting register)
TTT                     | LOAD

@ Read one word per pass through this loop.
NSSVSSSSTSTSSSSSSSTSN   | Mark: 00001010 00000010
SSSTN                   | PUSH 1 (starting register)
SSSTTTTN                | PUSH 15 (ptr)
TTT                     | LOAD
TSSS                    | ADD
TTT                     | LOAD

@ See if the loop is complete.
SSSTTTTN                | PUSH 15 (ptr)
TTT                     | LOAD
SSSTN                   | PUSH 1
TSST                    | SUBTRACT
NTSSSSSTSTSSSSSSSTTN    | BRZ > 00001010 00000011

@ Decrement the loop counter and loop again.
SSSTTTTN                | PUSH 15 (ptr)
TTT                     | LOAD
SSSTN                   | PUSH 1
TSST                    | SUBTRACT
SSSTTTTN                | PUSH 15 (ptr)
SNT                     | SWAP
TTS                     | STORE
NSNSSSSTSTSSSSSSSTSN    | JMP > 00001010 00000010

@ Return
NSSVSSSSTSTSSSSSSSTTN   | Mark: 00001010 00000011
NTN                     | RTS

@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
@ Name:
@   stackrotatereverse
@ Description:
@   Maximum rotation depth is 14. Stomps on heap[1]-heap[15].
@ Call Stack:
@   stack word n
@   ...
@   stack word 1
@   rotation depth (rd)  <-- TOS
@ Return Stack (n>rd=3):
@   stack word n
@   ...
@   stack word 2
@   stack word 1
@   stack word 3   <-- TOS
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
NSSVTSTTN               | Mark: 1011 (stackrotatereverse)

@ For the convenience of other functions, modulo the
@ rotation depth by the available registers.
SSSTTTSN                | PUSH 14
TSTT                    | MODULO

@ Use heap[15] for generating register addresses.
SSSTTTTN                | PUSH 15 (ptr)
SSSSN                   | PUSH 0
TTS                     | STORE

@ Dump one word from stack to heap each pass through the loop.
NSSVSSSSTSTTSSSSSSSSN   | Mark: 00001011 00000000
SNT                     | SWAP
SSSTN                   | PUSH 1 (starting register)
SSSTTTTN                | PUSH 15 (ptr)
TTT                     | LOAD
TSSS                    | ADD
SNT                     | SWAP
TTS                     | STORE

@ See if the loop is complete.
SNS                     | DUP
SSSTTTTN                | PUSH 15 (ptr)
TTT                     | LOAD
SSSTN                   | PUSH 1
TSSS                    | ADD
TSST                    | SUBTRACT
NTSSSSSTSTTSSSSSSSTN    | BRZ > 00001011 00000001

@ Increment the loop counter
SSSTTTTN                | PUSH 15 (ptr)
TTT                     | LOAD
SSSTN                   | PUSH 1
TSSS                    | ADD
SSSTTTTN                | PUSH 15 (ptr)
SNT                     | SWAP
TTS                     | STORE
NSNSSSSTSTTSSSSSSSSN    | JMP > 00001011 00000000

@ The correct number of words have been stored to registers.
@ Time to read them back in rotated order.

@ First, prepare the counter in heap[15] again.
NSSVSSSSTSTTSSSSSSSTN   | Mark: 00001011 00000001
SSSTN                   | PUSH 1
TSST                    | SUBTRACT
SNS                     | DUP
SSSTN                   | PUSH 1
TSST                    | SUBTRACT
SSSTTTTN                | PUSH 15 (ptr)
SNT                     | SWAP
TTS                     | STORE

@ Read one word per pass through this loop.
@ Store it behind 'rd' on the stack.
NSSVSSSSTSTTSSSSSSTSN   | Mark: 00001011 00000010
SSSTN                   | PUSH 1 (starting register)
SSSTTTTN                | PUSH 15 (ptr)
TTT                     | LOAD
TSSS                    | ADD
TTT                     | LOAD
SNT                     | SWAP

@ See if the loop is complete.
SSSTTTTN                | PUSH 15 (ptr)
TTT                     | LOAD
NTSSSSSTSTTSSSSSSTTN    | BRZ > 00001011 00000011

@ Decrement the loop counter and loop again.
SSSTTTTN                | PUSH 15 (ptr)
TTT                     | LOAD
SSSTN                   | PUSH 1
TSST                    | SUBTRACT
SSSTTTTN                | PUSH 15 (ptr)
SNT                     | SWAP
TTS                     | STORE
NSNSSSSTSTTSSSSSSTSN    | JMP > 00001011 00000010

@ Read in the final value manually and return.
NSSVSSSSTSTTSSSSSSTTN   | Mark: 00001011 00000011
SSSTN                   | PUSH 1 (starting register)
TSSS                    | ADD
TTT                     | LOAD
NTN                     | RTS

@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
@ Name:
@   deepdup
@ Description:
@   Duplicates an item deep on the stack, placing the duplicate on TOS.
@   By default, maximum depth is 11.
@   True maximum depth is (max depth of stackrotate & stackrotatereverse)-3.
@ Call Stack:
@   stack word n
@   ...
@   stack word 1
@   dupdepth  <-- TOS
@ Return Stack:
@   stack word n
@   ...
@   stack word 1
@   copy of stack word 3   <-- TOS
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
NSSVTTSSN               | Mark: 1100 (deepdup)

@ Copy 'dupdepth' and use it to bring forth the desired stack word.
SNS                     | DUP
SSSTN                   | PUSH 1
TSSS                    | ADD
NSTTSTTN                | JSR > 1011 (stackrotatereverse)

@ Copy the desired stack word and return it back into the stack.
SNS                     | DUP
SSSTTN                  | PUSH 3
NSTTSTTN                | JSR > 1011 (stackrotatereverse)
SSSTN                   | PUSH 1
TSSS                    | ADD
NSTTSTSN                | JSR > 1010 (stackrotate)
NTN                     | RTS

#endif