Remove nasm cruft, including file and variable names

This also removes the nasm check in `interp.rkt`, which was causing problems on
systems that should have been able to execute a86.

Author: pdarragh

a86/ast.rkt

@@ -18,8 +18,8 @@
   (λ (a x n)
     (match x
       [(? symbol?)
-       (unless (nasm-label? x)
-         (error n "label names must conform to nasm restrictions"))
+       (unless (asm-label? x)
+         (error n "label names must conform to restrictions"))
        (values a ($ x))]
       [($ _)
        (values a x)]
@@ -38,7 +38,7 @@
     (match x
       [(? offset?) (values a (exp-normalize x))]
       [(? register?) (values a x)]
-      [(? nasm-label? x) (values a ($ x))]
+      [(? asm-label? x) (values a ($ x))]
       [($ _) (values a x)]
       [_
        (error n "expects label, register, or offset; given ~v" x)])))
@@ -187,7 +187,7 @@
     [(list (? exp-unop?) (? exp?)) #t]
     [(list (? exp-binop?) (? exp?) (? exp?)) #t]
     [($ _) #t]
-    [(? nasm-label?) #t]
+    [(? asm-label?) #t]
     [(? 64-bit-integer?) #t]
     [_ #f]))
 
@@ -236,7 +236,7 @@
 (define (exp-normalize x)
   (match x
     [(? register?) x]
-    [(? nasm-label?) ($ x)]
+    [(? asm-label?) ($ x)]
     [(? Mem?) x]
     ;[(Offset e1) (Offset (exp-normalize e1))]
     [(Plus e1 e2)
@@ -259,7 +259,7 @@
 (provide label?)
 (define (label? x)
   (and (symbol? x)
-       (nasm-label? x)
+       (asm-label? x)
        (not (register? x))))
 
 (provide (struct-out $))
@@ -270,8 +270,8 @@
   (λ (x n)
     (unless (symbol? x)
       (error n "expects symbol; given ~v" x))
-    (unless (nasm-label? x)
-      (error n "label names must conform to nasm restrictions"))
+    (unless (asm-label? x)
+      (error n "label names must conform to restrictions"))
     (values x))
 
   #;#;#;#:methods gen:equal+hash
@@ -638,7 +638,7 @@
            (exp? (Plus-e1 x))
            (exp? (Plus-e2 x)))
       (register? x)
-      (nasm-label? x)
+      (asm-label? x)
       ($? x)
       (integer? x)))
 
@@ -746,7 +746,7 @@
 
 ;; (U Instruction Asm) ... -> Asm
 ;; Construct a "program", does some global well-formedness checking to help
-;; prevent confusing error messages as the nasm level
+;; prevent confusing error messages as the assembler level
 (define (prog . xs)
   (let ((p (apply seq xs)))
     (check-unique-label-decls p)
@@ -787,7 +787,7 @@
      (extern-decls asm)]))
 
 ;; Any -> Boolean
-(define (nasm-label? s)
+(define (asm-label? s)
   (and (symbol? s)
        (regexp-match #rx"^[a-zA-Z._?][a-zA-Z0-9_$#@~.?]*$" (symbol->string s))))
 
@@ -848,7 +848,7 @@
 ;; Symbol to Label
 
 ;; Symbol -> Label
-;; Produce a symbol that is a valid Nasm label
+;; Produce a symbol that is a valid assembly label
 ;; Guarantees that (eq? s1 s2) <=> (eq? (symbol->label s1) (symbol->label s1))
 (provide symbol->label)
 (define (symbol->label s)

a86/check-assembler.rkt

@@ -0,0 +1,72 @@
+#lang racket
+
+(provide check-clang-available
+         clang-version
+         clang-version-16+?)
+
+(require racket/gui/dynamic)
+
+(define clang-missing-msg
+  #<<HERE
+clang not found: either you have not installed clang
+or it cannot be found in your PATH: ~a.~a
+HERE
+  )
+
+(define finder-launch-msg
+  #<<HERE
+
+
+It appears you launched DrRacket using Finder, which
+does not properly set up the PATH environment variable.
+Try launching DrRacket from the command line using the
+'drracket' command.
+HERE
+  )
+
+(define (macos?)
+  (eq? 'macosx (system-type 'os)))
+
+;; This will lie if you happen to run drracket from /, but that's OK.
+(define (launched-with-finder?)
+  (equal? (string->path "/") (find-system-path 'orig-dir)))
+
+(define (drracket?)
+  (gui-available?))
+
+;; -> [Maybe String]
+(define (clang-version-string)
+  (parameterize ([current-output-port (open-output-string)]
+                 [current-error-port (open-output-string)])
+    (and (system (format "~aclang -v 2>&1"
+                         (if (macos?)
+                             "arch -x86_64 "
+                             "")))
+         (get-output-string (current-output-port)))))
+
+(define (clang-version-16+?)
+  (match (clang-version)
+    [(list major _ _)
+     (>= major 16)]
+    [_ #f]))
+
+;; -> [Maybe (list Natural Natural Natural)]
+(define (clang-version)
+  (match (clang-version-string)
+    [#f #f]
+    [(regexp #rx"version ([0-9]+)\\.([0-9]+)\\.([0-9]+) "
+             (list _
+                   (app string->number major)
+                   (app string->number minor)
+                   (app string->number patch)))
+     (list major minor patch)]))
+
+;; -> Void
+(define (check-clang-available)
+  (define v (clang-version))
+  (unless v
+    (error (format clang-missing-msg
+                   (getenv "PATH")
+                   (if (and (drracket?) (macos?) (launched-with-finder?)) finder-launch-msg ""))))
+  (unless (clang-version-16+?)
+    (eprintf "clang 16.0.0 or later is recommended; some features may not work as expected.\n")))

a86/check-nasm.rkt

@@ -9,12 +9,12 @@
 
 (define-logger a86)
 
-(require "printer.rkt" "ast.rkt" "callback.rkt" "check-nasm.rkt"
+(require "printer.rkt" "ast.rkt" "callback.rkt" "check-assembler.rkt"
          (rename-in ffi/unsafe [-> _->]))
 (require (submod "printer.rkt" private))
 
-;; Check NASM availability when required to fail fast.
-(check-nasm-available)
+;; Check clang availability when required to fail fast.
+(check-clang-available)
 
 ;; Bail out if we're not on an x86_64 Racket.
 (unless (eq? 'x86_64 (system-type 'arch))
@@ -84,7 +84,7 @@
 
   (log-a86-info (~v a))
 
-  (define t.s   (make-temporary-file "nasm~a.s"))
+  (define t.s   (make-temporary-file "clang-~a.s"))
   (define t.o   (path-replace-extension t.s #".o"))
   (define t.so  (path-replace-extension t.s #".so"))
   (define t.in  (path-replace-extension t.s #".in"))
@@ -123,7 +123,7 @@
                          (debug-transform a*)
                          a*)))))
 
-  (nasm t.s t.o)
+  (clang t.s t.o)
   (ld t.o t.so)
 
   (define libt.so (ffi-lib t.so))
@@ -206,24 +206,24 @@
          (add-between (map (lambda (s) (string-append "\"" s "\"")) xs)
                       " ")))
 
-;;; Utilities for calling nasm and linker with informative error messages
+;;; Utilities for calling clang and linker with informative error messages
 
-(struct exn:nasm exn:fail:user ())
-(define nasm-msg
+(struct exn:clang exn:fail:user ())
+(define assembly-error-msg
   (string-append
    "assembly error: make sure to use `prog` to construct an assembly program\n"
    "if you did and still get this error; please share with course staff."))
 
-(define (nasm:error msg)
-  (raise (exn:nasm (format "~a\n\n~a~a" nasm-msg msg (nasm-offending-line msg))
-                   (current-continuation-marks))))
+(define (clang:error msg)
+  (raise (exn:clang (format "~a\n\n~a~a" assembly-error-msg msg (assembly-offending-line msg))
+                    (current-continuation-marks))))
 
-(define (nasm-offending-line msg)
+(define (assembly-offending-line msg)
   (match (regexp-match
           "(.*):([0-9]+): error: " msg)
     [(list _ (app string->path file) (app string->number line))
      (format
-      "\nnasm offending line: ~a"
+      "\noffending line: ~a"
       (with-input-from-file file
         (thunk
          (let loop ([l (read-line)]
@@ -234,8 +234,8 @@
     [_ ""]))
 
 
-;; run nasm on t.s to create t.o
-(define (nasm t.s t.o)
+;; run clang on t.s to create t.o
+(define (clang t.s t.o)
   (define err-port (open-output-string))
   (define fmt (if (eq? (system-type 'os) 'macosx) 'macho64 'elf64))
   (define prefix
@@ -245,7 +245,7 @@
 
   (unless (parameterize ((current-error-port err-port))
             (system (format "~a clang -c ~a -o ~a" prefix t.s t.o)))
-    (nasm:error (get-output-string err-port))))
+    (clang:error (get-output-string err-port))))
 
 (struct exn:ld exn:fail:user ())
 (define (ld:error msg)