From 8fcf2b36b29e3c33ef080d83f888403621d06ee8 Mon Sep 17 00:00:00 2001
From: Jan Nieuwenhuizen <janneke@gnu.org>
Date: Thu, 10 Aug 2017 20:57:43 +0200
Subject: [PATCH] mescc: Tinycc support: --*p, ++*p.

* module/language/c99/compiler.mes (expr->accu): Remove specific --/++.
  (expr->accu*): Support p, *p.
* scaffold/tests/76-pointer-arithmetic.c (test): Test it.
---
 module/language/c99/compiler.mes       | 51 ++++----------------------
 scaffold/tests/76-pointer-arithmetic.c | 11 ++++++
 2 files changed, 18 insertions(+), 44 deletions(-)

diff --git a/module/language/c99/compiler.mes b/module/language/c99/compiler.mes
index a7f06ee8..96f2d46c 100644
--- a/module/language/c99/compiler.mes
+++ b/module/language/c99/compiler.mes
@@ -697,14 +697,6 @@
                                                 ((2) (i386:word-mem->accu))
                                                 (else (i386:mem->accu))))))))
 
-        ((de-ref (post-inc (p-expr (ident ,name))))
-         (let* ((info ((expr->accu info) `(de-ref (p-expr (ident ,name)))))
-                (type (ident->type info name))
-                (ptr (ident->pointer info name))
-                (size (if (= ptr 1) (ast-type->size info type)
-                          4)))
-           (append-text info ((ident-add info) name size))))
-
         ((de-ref ,expr)
          (let* ((info ((expr->accu info) expr))
                 (ptr (expr->pointer info expr))
@@ -749,42 +741,6 @@
         ((cond-expr . ,cond-expr)
          ((ast->info info) `(expr-stmt ,o)))
 
-        ((post-inc (p-expr (ident ,name)))
-         (let* ((type (ident->type info name))
-                (ptr (ident->pointer info name))
-                (size (cond ((= ptr 1) (ident->size info name))
-                            ((> ptr 1) 4)
-                            (else 1))))
-           (append-text info (append ((ident->accu info) name)
-                                     ((ident-add info) name size)))))
-
-        ((post-dec (p-expr (ident ,name)))
-         (let* ((type (ident->type info name))
-                (ptr (ident->pointer info name))
-                (size (cond ((= ptr 1) (ident->size info name))
-                            ((> ptr 1) 4)
-                            (else 1))))
-           (append-text info (append ((ident->accu info) name)
-                                     ((ident-add info) name (- size))))))
-
-        ((pre-inc (p-expr (ident ,name)))
-         (let* ((type (ident->type info name))
-                (ptr (ident->pointer info name))
-                (size (cond ((= ptr 1) (ident->size info name))
-                            ((> ptr 1) 4)
-                            (else 1))))
-           (append-text info (append ((ident-add info) name size)
-                                     ((ident->accu info) name)))))
-
-        ((pre-dec (p-expr (ident ,name)))
-         (let* ((type (ident->type info name))
-                (ptr (ident->pointer info name))
-                (size (cond ((= ptr 1) (ident->size info name))
-                            ((> ptr 1) 4)
-                            (else 1))))
-           (append-text info (append ((ident-add info) name (- size))
-                                     ((ident->accu info) name)))))
-
         ((post-inc ,expr)
          (let* ((info (append ((expr->accu info) expr)))
                 (info (append-text info (wrap-as (i386:push-accu))))
@@ -1090,6 +1046,13 @@
 (define (expr->accu* info)
   (lambda (o)
     (pmatch o
+
+      ((p-expr (ident ,name))
+       (append-text info ((ident-address->accu info) name)))
+
+      ((de-ref ,expr)
+       ((expr->accu info) expr))
+
       ;; foo[bar]
       ((array-ref ,index (p-expr (ident ,array)))
        (let* ((info ((expr->accu info) index))
diff --git a/scaffold/tests/76-pointer-arithmetic.c b/scaffold/tests/76-pointer-arithmetic.c
index 8e0c278a..28b63344 100644
--- a/scaffold/tests/76-pointer-arithmetic.c
+++ b/scaffold/tests/76-pointer-arithmetic.c
@@ -19,6 +19,9 @@
  */
 
 #include "30-test.i"
+#include <stdio.h>
+
+char *list[2] = {"foo\n", "bar\n"};
 
 int
 test ()
@@ -43,5 +46,13 @@ test ()
   if (ppv + 1 != 8) return 11;
   if (ppi + 1 != 8) return 12;
 
+  char **p = list;
+  ++*p;
+  eputs (*p);
+  if (strcmp (*p, "oo\n")) return 1;
+  --*p;
+  eputs (*p);
+  if (strcmp (*p, "foo\n")) return 2;
+
   return 0;
 }