[Ongoing] Rewrite frontend to use Flex/Bison

This is a merge of another experiment, so the changes are large:

- separated "modules" directory into frontend/backend
  - adjusted module names and moved files for this to happen
- removed modules lexer & parser
- removed all the unit tests (most were outdated)
- added Bison, flex, and C development tools to manifest.scm
- added lexer.l, a source file used by the flex utility with a functioning lexing implementation
- added parser.y, a source file used by the bison utility with a functioning parser implementation
- added node.c and node.h, which parser.y uses to construct an AST of a C source file (up to binary ops)
- added driver.c, a Guile-C interface that provides a module to scheme programs
- added a Makefile to make all of this
- added stuff to .gitignore

1 files changed, 16 insertions, 0 deletions

diff --git a/src/backend/generator/allocate.scm b/src/backend/generator/allocate.scm
new file mode 100644
index 0000000..0d417db
--- /dev/null
+++ b/src/backend/generator/allocate.scm
@@ -0,0 +1,16 @@
+(define-module (backend generator allocate)
+  #:use-module (backend utils assign-stack)
+  #:export (expansion->allocate))
+
+
+(define (expansion->allocate ast)
+  (define (allocate n)
+    (cond
+     ((null? n) n)
+     ((eq? (car n) 'tmp)
+      (list 'stack (make-location (cadr n))))
+     ((list? (car n))
+      (cons (allocate (car n)) (allocate (cdr n))))
+     (#t
+      (cons (car n) (allocate (cdr n))))))
+  (allocate ast))