From b1c99512da3ac712f4e3688e77ed1eed7e84475b Mon Sep 17 00:00:00 2001
From: Alain Emilia Anna Zscheile <fogti+devel@ytrizja.de>
Date: Thu, 22 Feb 2024 23:10:54 +0100
Subject: [PATCH] initial commit

---
 .gitignore         |  6 ++++++
 dune-project       | 19 +++++++++++++++++++
 lib/dune           |  7 +++++++
 lib/layout.ml      | 45 +++++++++++++++++++++++++++++++++++++++++++++
 lib/layout.mli     | 17 +++++++++++++++++
 lib/stackAction.ml | 16 ++++++++++++++++
 yanaijepeux.opam   | 27 +++++++++++++++++++++++++++
 7 files changed, 137 insertions(+)
 create mode 100644 .gitignore
 create mode 100644 dune-project
 create mode 100644 lib/dune
 create mode 100644 lib/layout.ml
 create mode 100644 lib/layout.mli
 create mode 100644 lib/stackAction.ml
 create mode 100644 yanaijepeux.opam

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..dc9f764
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,6 @@
+/_build
+/yanais.opam
+*.cmi
+*.cmx
+*.exe
+*.o
diff --git a/dune-project b/dune-project
new file mode 100644
index 0000000..44a5eda
--- /dev/null
+++ b/dune-project
@@ -0,0 +1,19 @@
+(lang dune 2.7)
+(using menhir 2.0)
+
+(name yanaijepeux)
+(version 0.0.1)
+(authors "Alain Emilia Anna Zscheile <fogti+devel@ytrizja.de>")
+(license "Apache-2.0 OR ISC")
+
+(package
+  (name yanaijepeux)
+  (synopsis "Yanais-associated utilities")
+  (description "Yanais-associated utilities")
+  (depends
+    (gen (>= 0.5))
+    (integers (>= 0.2))
+  )
+)
+
+(generate_opam_files)
diff --git a/lib/dune b/lib/dune
new file mode 100644
index 0000000..7b8021f
--- /dev/null
+++ b/lib/dune
@@ -0,0 +1,7 @@
+(library
+  (name yanaijepeux)
+  (public_name yanaijepeux)
+  (synopsis "Yanais-associated utilities")
+  (libraries))
+
+(documentation)
diff --git a/lib/layout.ml b/lib/layout.ml
new file mode 100644
index 0000000..3596372
--- /dev/null
+++ b/lib/layout.ml
@@ -0,0 +1,45 @@
+(** a memory layout *)
+type t = {
+    size : int;
+
+    align_exp : char;
+    (** alignment = 1 << align_exp *)
+  }
+
+open Int
+
+let show x = "Layout { size = " ^ (string_of_int x.size) ^ "; align_exp = " ^ (Char.code x.align_exp |> string_of_int) ^ "}"
+
+let alignment_of_exp x = shift_left 1 (Char.code x)
+
+let alignment x = alignment_of_exp x.align_exp
+
+let max_size_for_align_exp x =
+  let y = alignment_of_exp x in
+  let isz_max_sc = shift_right max_int 1 |> succ in
+  isz_max_sc - y
+
+(** appends a layout to this one, returns new layout and the offset *)
+let push orig next =
+  let align_exp = max (Char.code orig.align_exp) (Char.code next.align_exp) |> Char.chr in
+  let align_exp_cc = Char.code align_exp in
+  if (align_exp_cc >= 32) || (align_exp_cc < 0) then Option.none else
+
+  (* fill up ourselves so that the other element is correctly aligned *)
+  let smask_sh = alignment next in
+  let smask = pred smask_sh in
+  let smasked = logand orig.size smask in
+
+  (* align size *)
+  let size = if compare smasked zero == 0 then orig.size else (
+    add (sub orig.size smasked) smask_sh
+  ) in
+
+  let offset = size in
+  let size = size + next.size in
+  if size <= max_size_for_align_exp align_exp
+    then Option.some ({ size; align_exp; }, offset)
+    else Option.none
+
+(** finishes a layout by inserting padding at the end to ensure alignment *)
+let finish orig = push orig { size = 0; align_exp = orig.align_exp }
diff --git a/lib/layout.mli b/lib/layout.mli
new file mode 100644
index 0000000..2c119fc
--- /dev/null
+++ b/lib/layout.mli
@@ -0,0 +1,17 @@
+(** a memory layout *)
+type t = {
+    size : int;
+
+    align_exp : char;
+    (** alignment = 1 << align_exp *)
+  }
+
+val show : t -> string
+
+val alignment : t -> int
+
+(** appends a layout to this one, returns new layout and the offset *)
+val push : t -> t -> (t * int) option
+
+(** finishes a layout by inserting padding at the end to ensure alignment (might fail when overflowing) *)
+val finish : t -> (t * int) option
diff --git a/lib/stackAction.ml b/lib/stackAction.ml
new file mode 100644
index 0000000..d6e0e85
--- /dev/null
+++ b/lib/stackAction.ml
@@ -0,0 +1,16 @@
+(** A stack action (pop is run first, then push sequentially) *)
+type 'a t =
+  { pop  : int
+  ; push : 'a list
+  }
+
+let merge lhs rhs =
+  (* merge lhs.push and rhs.pop first *)
+  let rec compensate push pop = match (push, pop) with
+    | (_, 0) -> (push, pop)
+    | ([], _) -> (push, pop)
+    | (_::xs, _) -> compensate xs (pop - 1)
+  in let (push, pop) = compensate lhs.push rhs.pop in
+  { pop = lhs.pop + pop; push = List.append push rhs.push; }
+
+let empty = { pop = 0; push = []; }
diff --git a/yanaijepeux.opam b/yanaijepeux.opam
new file mode 100644
index 0000000..c604dab
--- /dev/null
+++ b/yanaijepeux.opam
@@ -0,0 +1,27 @@
+# This file is generated by dune, edit dune-project instead
+opam-version: "2.0"
+version: "0.0.1"
+synopsis: "Yanais-associated utilities"
+description: "Yanais-associated utilities"
+authors: ["Alain Emilia Anna Zscheile <fogti+devel@ytrizja.de>"]
+license: "Apache-2.0 OR ISC"
+depends: [
+  "dune" {>= "2.7"}
+  "gen" {>= "0.5"}
+  "integers" {>= "0.2"}
+  "odoc" {with-doc}
+]
+build: [
+  ["dune" "subst"] {dev}
+  [
+    "dune"
+    "build"
+    "-p"
+    name
+    "-j"
+    jobs
+    "@install"
+    "@runtest" {with-test}
+    "@doc" {with-doc}
+  ]
+]