1 files changed, 107 insertions, 0 deletions
diff --git a/fetch-wasm-instrs.lisp b/fetch-wasm-instrs.lisp
new file mode 100644
index 0000000..4735214
--- /dev/null
+++ b/fetch-wasm-instrs.lisp
@@ -0,0 +1,107 @@
+(ql:quickload '(#:dexador #:cl-ppcre #:flatbind))
+
+(defpackage #:fetch-wasm-instrs
+  (:use #:cl)
+  (:import-from #:flatbind #:do>))
+
+(in-package #:fetch-wasm-instrs)
+
+
+(defvar +source-url+
+  "https://raw.githubusercontent.com/WebAssembly/spec/main/document/core/appendix/index-instructions.py"
+
+  "Incredibly obnoxiously, the only textual up-to-date table of all the instructions exists in a fucking python file.")
+
+(defun fetch-source-file ()
+  (dexador:get +source-url+))
+
+(defparameter +start-instrs-pattern+ "INSTRUCTIONS = [
+")
+
+(defparameter +end-instrs-pattern+ "
+]")
+
+(defun trim-junk (str)
+  (string-trim '(#\space #\tab #\newline #\return #\( #\) #\comma) str))
+
+(defun parse-instruction (str)
+  (let ((str (trim-junk str)))
+   (ppcre:split
+    ", ?"
+    (subseq str #.(length "Instruction(") (- (length str) 2)))))
+
+(defun excise-instructions (source)
+  (let* ((start-pos (+ (length +start-instrs-pattern+)
+                       (search +start-instrs-pattern+ source)))
+         (end-pos (search +end-instrs-pattern+ source :start2 start-pos)))
+    (mapcar #'parse-instruction
+            (ppcre:split "\\n" (subseq source start-pos end-pos)))))
+
+(defun parse-hex (str)
+  (do>
+    (ok groups) := (ppcre:scan-to-strings "hex{([A-F0-9]+)}" str)
+    :when (and ok (vectorp groups))
+    hex := (elt groups 0)
+    (parse-integer hex :radix 16)))
+
+(defun parse-code (str)
+  (remove-if-not #'identity (mapcar #'parse-hex (ppcre:split "~" str))))
+
+(defun dropchar? (c) (find c "\\'{}"))
+
+(defun clean-string (str &optional extra)
+  (remove-if
+   (if extra
+       (lambda (c) (or (dropchar? c) (find c extra)))
+       #'dropchar?)
+   (ppcre:regex-replace "\\\\K" (subseq str 1) "")))
+
+(defun parse-instr (str)
+  (when (not (string-equal "None" str))
+    (destructuring-bind
+        (first . rest)
+        (loop :for part :in (ppcre:split "~" (clean-string str))
+              :collect (ppcre:regex-replace "ast" part "*"))
+      (cons (string-downcase
+             (ppcre:regex-replace
+              "^(LOCAL|GLOBAL|TABLE|MEMORY|DATA|ELEM|REF)"
+              first
+              "\\1."))
+            rest))))
+
+(defun parse-type-list (str)
+  (loop :for part :in (ppcre:split "~" (clean-string str "[]_^"))
+        :collect (alexandria:make-keyword
+                  (ppcre:regex-replace "ast" part "*"))))
+
+(defun parse-instr-type (str)
+  (when str
+    (mapcar #'parse-type-list (ppcre:split " to " (clean-string str)))))
+
+(defun make-instr (instr code type)
+  (list :instr instr
+        :code code
+        :type type))
+
+(defun get-all-instructions ()
+  (do>
+    str :when= (fetch-source-file)
+    entries := (excise-instructions str)
+    (loop :for (namestr codestr typestr . more) :in entries
+          :for instr := (parse-instr namestr)
+          :for code := (parse-code codestr)
+          :for type := (parse-instr-type typestr)
+          :when instr
+            :collect (make-instr instr code type))))
+
+(format t "Fetching all instructions from~%    ~a~%" +)
+(let ((instrs (get-all-instructions)))
+  (format t "Writing to disk in ./instrs.sexp~%")
+  (with-open-file (out "instrs.sexp"
+                       :direction :output
+                       :if-exists :supersede
+                       :if-does-not-exist :create)
+    (write instrs :stream out)))
+(format t "DONE~%")
+
+(uiop:quit)