Module Tolk.Graph

UOp graphs as text: the format of the programs the disk cache keeps (Codegen.to_program) and of the goldens, which tolk's test/README.md specifies.

A graph is the nodes under a sink, one line each, in topological order:

<index> <op> <dtype> [<sources>] <arg>

test/gen/graph.py writes the same text from tinygrad's graphs, so a graph golden reads into the UOps tinygrad built, and a graph built here writes as the golden tinygrad recorded.

#val to_string : Ops.t -> string

to_string sink is the graph under sink. A node comes after its sources, visited in order, and after the nodes its argument holds.

#val of_string : string -> Ops.t

of_string text is the sink of the graph text, the node of its last line. Reading takes the graph's numbers: every number Ops.unique_num returns afterwards is greater than each slot of the graph and each number of its ranges' axes.

Raises Failure naming the node, by its line's position, and what is wrong with it if text is empty, a line does not read, an index is not its line's position, a source or a node in an argument is not an earlier line, an argument does not fit its operation, a node's written data type is not the one its operation, sources and argument derive, or a slot or a number of a range's axes is max_int, which leaves no greater number.

Disk

val cached : 
  table:string ->
  key:string ->
  valid:(Ops.t -> bool) ->
  (unit -> Ops.t) ->
  Ops.t * bool

cached ~table ~key ~valid make is the graph that the Helpers.Diskcache holds for key in table, and true, if its entry reads as a graph that valid accepts; otherwise it is make (), which replaces the entry, and false. An entry that does not read, or cannot be read, is made anew, as one that is missing.

Raises Sys_error if the entry cannot be written.