X-Git-Url: http://git.subgeniuskitty.com/vvhitespace/.git/blobdiff_plain/32c440bf6f1f2199c3e925f32bd3b621039605e6..b6bea2cfd080c66a11074dd47484711482a2907a:/stdlib/README.md

diff --git a/stdlib/README.md b/stdlib/README.md
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--- a/stdlib/README.md
+++ b/stdlib/README.md
@@ -1,29 +1,101 @@
+# Overview #
+
+This folder contains a library of useful functions written in VVhitespace.
+Standard include guards are used with `cpp` to include the stdlib in user
+programs. For an example, see `examples/hello-stdlib`. This also means
+`cpp` syntax must be respected.
+
 # Reservations #
 
+Since all labels share a global namespace, the standard library makes the
+following reservations:
+
 ## Label ##
 
     00000000 0xxxxxxx - reserved for stdlib function entry points
-    00000000 1xxxxxxx - unassigned
+    00000000 1xxxxxxx - available for use in user programs
     0xxxxxxx xxxxxxxx - reserved for private use by stdlib
     1xxxxxxx xxxxxxxx - available for use in user programs
 
-## Heap ##
+## Heap and Pointers ##
+
+The first 16 heap addresses (`0-15`) are reserved when using the stdlib.
+Within that reservation, heap[0] is used by `random` and the block
+heap[1]-heap[15] by the stack rotation subroutines which time-share
+pseudo-registers between the various stdlib subroutines.
 
-    The first 256 heap addresses are reserved when using the stdlib.
+By convention, functions which return a pointer will use the address `0` to
+represent a `NULL` pointer.
 
 # Entry Points #
 
 The following labels are entry points to stdlib functions. Read the
 header comment for each function to learn the call and return stack.
 
-    stdio.pvvs:
-           1000 - print string from stack
-           1001 - print string from heap
+         000xxx - reserved
+         001xxx - core functions
+           1000 ----- printf                        (stdio.pvvs)
+           1001 ----- print number from stack       (stdio.pvvs)
+           1010 ----- stackrotate                   (stack.pvvs)
+           1011 ----- stackrotatereverse            (stack.pvvs)
+           1100 ----- deepdup                       (stack.pvvs)
+         010xxx - math functions
+          10000 ----- random                        (math.pvvs)
+          10001 ----- absolute value                (math.pvvs)
+          10010 ----- greatest common divisor       (math.pvvs)
+         011xxx - heap functions
+          11000 ----- memset                        (heap.pvvs)
+          11001 ----- memcpy                        (heap.pvvs)
+          11010 ----- memrand                       (heap.pvvs)
+          11011 ----- memcmp                        (heap.pvvs)
+          11100 ----- memsrch                       (heap.pvvs)
+          11101 ----- <empty>
+          11110 ----- slurp                         (heap.pvvs)
+          11111 ----- spew                          (heap.pvvs)
+         100xxx - string functions
+         100000 ----- strlen                        (string.pvvs)
+         100001 ----- isdigit                       (string.pvvs)
+         101xxx - logic functions
+         101000 ----- not                           (logic.pvvs)
+         101001 ----- and                           (logic.pvvs)
+         101010 ----- or                            (logic.pvvs)
+         101011 ----- xor                           (logic.pvvs)
+         101100 ----- rshift                        (logic.pvvs)
+         101101 ----- lshift                        (logic.pvvs)
+         110xxx - conversion functions
+         110000 ----- atoi                          (convert.pvvs)
+         111xxx - debug functions
+         111000 ----- dump heap                     (debug.pvvs)
+         111001 ----- dump stack                    (debug.pvvs)
+         111010 ----- print sign                    (debug.pvvs)
+         111011 ----- print magnitude               (debug.pvvs)
+         111100 ----- print string                  (debug.pvvs)
+         111101 ----- print signed number           (debug.pvvs)
+        1xxxxxx - reserved for less common entry points
+        1000000 ----- lowbitand                     (logic.pvvs)
+        1000001 ----- <empty>
+        1000010 ----- print sign of number          (stdio.pvvs)
+        1000011 ----- print magnitude of number     (stdio.pvvs)
+        1000100 ----- print string from stack       (stdio.pvvs)
+        1000101 ----- print string from heap        (stdio.pvvs)
 
 # Misc #
 
-By convention, each public stdlib label will have 8 bits of
-private label space associated with it, formed as follows:
+## Private Label Space ##
+
+By convention, each public stdlib label will have 8 bits of private label space
+associated with it, formed as follows:
 
     00001000 xxxxxxxx - for use by 1000
     00001001 xxxxxxxx - for use by 1001
+    ...etc
+
+## Extending Heap Reservation ##
+
+By default, the stdlib uses the first 16 heap addresses. All heap access (other
+than heap[0] as a seed) occurs through `stackrotate` and `stackrotatereverse`.
+Edit these functions to increase the stdlib's heap reservation.
+
+The remainder of the stdlib is written to automatically use the new allocation.
+Functions like `printf`, for example, allow more substitutions when the heap
+allocation is increased.