From 11d240e756f48c28664e799fe2f8d442bd4a11b7 Mon Sep 17 00:00:00 2001
From: Jan Nieuwenhuizen <janneke@gnu.org>
Date: Sun, 6 Aug 2017 18:49:19 +0200
Subject: [PATCH] mescc: Tinycc support: struct assign by value.

* module/language/c99/compiler.mes (base->ident): Remove.
  (accu->ident): Use them to support assign of size >4 by value.
* scaffold/tests/7h-struct-assign.c: Test it.
* make.scm (add-scaffold-test): Build it.
* module/mes/as-i386.mes (i386:base->local): Remove.
  (i386:accu*n->local):
  (i386:accu*n->label): New functions.
* module/mes/as-i386.scm: Export them.
* stage0/x86.M1: (mov____%ebx,0x32):
  (mov____%ebx,0x32(%ebp)):
  (mov____%ebx,0x8(%ebp)):
  (mov____%ebx,0x8(%edx)):
  (mov____%ecx,0x32(%ebp)):
  (mov____%ecx,0x8(%ebp)):
  (mov____0x32(%eax),%ebx):
  (mov____0x32(%eax),%ecx):
  (mov____0x8(%eax),%ebx): New define.
---
 make.scm                          |  3 +-
 module/language/c99/compiler.mes  | 21 +++++++-------
 module/mes/as-i386.mes            | 33 ++++++++++++++++------
 module/mes/as-i386.scm            |  3 +-
 scaffold/tests/7h-struct-assign.c | 47 +++++++++++++++++++++++++++++++
 stage0/x86.M1                     | 10 +++++++
 6 files changed, 95 insertions(+), 22 deletions(-)
 create mode 100644 scaffold/tests/7h-struct-assign.c

diff --git a/make.scm b/make.scm
index 8be7ca89..d245149d 100755
--- a/make.scm
+++ b/make.scm
@@ -166,7 +166,8 @@ exec ${GUILE-guile} --no-auto-compile -L . -L guile -C . -C guile -s "$0" ${1+"$
    "7d-cast-char"
    "7e-struct-array-access"
    "7f-struct-pointer-arithmetic"
-   "7g-struct-byte-word-field"))
+   "7g-struct-byte-word-field"
+   "7h-struct-assign"))
 
 (add-target (group "check-scaffold-tests/7" #:dependencies (filter (target-prefix? "check-scaffold/tests/7") %targets)))
 
diff --git a/module/language/c99/compiler.mes b/module/language/c99/compiler.mes
index bd7f914a..02e66bfc 100644
--- a/module/language/c99/compiler.mes
+++ b/module/language/c99/compiler.mes
@@ -380,16 +380,14 @@
 
 (define (accu->ident info)
   (lambda (o)
-    (let ((local (assoc-ref (.locals info) o)))
-      (if local (wrap-as (i386:accu->local (local:id local)))
-          (let ((ptr (ident->pointer info o)))
-            (list (i386:accu->label `(#:address ,o))))))))
-
-(define (base->ident info)
-  (lambda (o)
-    (let ((local (assoc-ref (.locals info) o)))
-      (if local (wrap-as (i386:base->local (local:id local)))
-          (list (i386:base->label `(#:address ,o)))))))
+    (let* ((local (assoc-ref (.locals info) o))
+           (ptr (ident->pointer info o))
+           (size (if (= ptr -1) (ident->size info o)
+                     4)))
+      (if local (if (<= size 4) (wrap-as (i386:accu->local (local:id local)))
+                    (wrap-as (i386:accu*n->local (local:id local) size)))
+          (if (<= size 4) (wrap-as (i386:accu->label o))
+              (wrap-as (i386:accu*n->label o size)))))))
 
 (define (base->ident-address info)
   (lambda (o)
@@ -962,7 +960,8 @@
                                                     ((equal? op "<<=") (wrap-as (i386:accu<<base)))
                                                     (else (error (format #f "mescc: op ~a not supported: ~a\n" op o)))))))))
            (pmatch a
-             ((p-expr (ident ,name)) (append-text info ((accu->ident info) name)))
+             ((p-expr (ident ,name))
+              (append-text info ((accu->ident info) name)))
              ((d-sel (ident ,field) ,p-expr)
               (let* ((type (p-expr->type info p-expr))
                      (offset (field-offset info type field))
diff --git a/module/mes/as-i386.mes b/module/mes/as-i386.mes
index 0a94de23..3200d5ef 100644
--- a/module/mes/as-i386.mes
+++ b/module/mes/as-i386.mes
@@ -101,15 +101,18 @@
     `(,(if (< (abs n) #x80) `("mov____%eax,0x8(%ebp)" (#:immediate1 ,n))
            `("mov____%eax,0x32(%ebp)" (#:immediate ,n))))))
 
-(define (i386:base->local n)
-  (or n (error "invalid value: base->local: " n))
-  `(("mov____%edx,0x8(%ebp)" ,(- 0 (* 4 n))))) ; mov    %edx,-<0xn>(%ebp)
-
-(define (i386:base->local n)
-  (or n (error "invalid value: base->local: " n))
-  (let ((n (- 0 (* 4 n))))
-    `((if (< (abs n) #x80) `("mov____%edx,0x8(%ebp)" (#:immediate1 ,n))
-          `("mov____%edx,0x32(%ebp)" (#:immediate ,n))))))
+(define (i386:accu*n->local i n)
+  (or n (error "invalid value: accu->local: " n))
+  (let ((o (- 0 (* 4 i))))
+    (let loop ((i 0))
+      (if (>= i n) '()  ;; FIXME: byte, word-sized
+          (let ((o (+ o i)))
+            (append
+             (if (< (abs o) #x80) `(("mov____0x8(%eax),%ebx" (#:immediate1 ,i))
+                                    ("mov____%ebx,0x8(%ebp)" (#:immediate1 ,o)))
+                 `(("mov____0x8(%eax),%ebx" (#:immediate1 ,i))
+                   ("mov____%ebx,0x32(%ebp)" (#:immediate ,o))))
+             (loop (+ i 4))))))))
 
 (define (i386:local->accu n)
   (or n (error "invalid value: local->accu: " n))
@@ -223,6 +226,18 @@
 (define (i386:accu->label label)
   `(("mov____%eax,0x32" (#:address ,label)))) ; mov    %eax,0x<label>
 
+(define (i386:accu*n->label label n)
+  (append
+   '(("push___%edx"))
+   (let loop ((i 0))
+     (if (>= i n) '() ;; FIXME: byte, word-sized
+         (append
+          `(("mov____$i32,%edx" (#:address ,label))
+            ("mov____0x8(%eax),%ebx" (#:immediate1 ,i))
+            ("mov____%ebx,0x8(%edx)" (#:immediate1 ,i)))
+          (loop (+ i 4)))))
+   '(("pop____%edx"))))
+
 (define (i386:accu-shl n)
   (or n (error "invalid value: accu:shl n: " n))
   `(("shl____$i8,%eax" (#:immediate1 ,n)))) ; shl    $0x8,%eax
diff --git a/module/mes/as-i386.scm b/module/mes/as-i386.scm
index d1cc0f3c..54a7bcd0 100644
--- a/module/mes/as-i386.scm
+++ b/module/mes/as-i386.scm
@@ -30,6 +30,8 @@
   #:export (
             i386:accu%base
             i386:accu*base
+            i386:accu*n->label
+            i386:accu*n->local
             i386:accu+accu
             i386:accu+base
             i386:accu+value
@@ -62,7 +64,6 @@
             i386:base->accu
             i386:base->accu-mem
             i386:base->label
-            i386:base->local
             i386:base-mem->accu-mem
             i386:base-mem+n->accu
             i386:base-mem->accu
diff --git a/scaffold/tests/7h-struct-assign.c b/scaffold/tests/7h-struct-assign.c
new file mode 100644
index 00000000..4de679f0
--- /dev/null
+++ b/scaffold/tests/7h-struct-assign.c
@@ -0,0 +1,47 @@
+/* -*-comment-start: "//";comment-end:""-*-
+ * Mes --- Maxwell Equations of Software
+ * Copyright © 2017 Jan Nieuwenhuizen <janneke@gnu.org>
+ *
+ * This file is part of Mes.
+ *
+ * Mes is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or (at
+ * your option) any later version.
+ *
+ * Mes is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Mes.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "30-test.i"
+#include <string.h>
+
+struct string {
+  char *str;
+  int len;
+};
+
+struct string g_t;
+
+int
+test ()
+{
+  struct string s = {"hallo"};
+  s.len = strlen (s.str);
+  struct string t;
+  t = s;
+
+  if (t.len != s.len) return 1;
+  if (strcmp (t.str, s.str)) return 2;
+
+  g_t = s;
+  if (g_t.len != s.len) return 3;
+  if (strcmp (g_t.str, s.str)) return 4;
+
+  return 0;
+}
diff --git a/stage0/x86.M1 b/stage0/x86.M1
index 3d28954d..bb68b670 100644
--- a/stage0/x86.M1
+++ b/stage0/x86.M1
@@ -92,8 +92,14 @@ DEFINE mov____%eax,0x8(%edx) 8942
 DEFINE mov____%ebp,%eax 89e8
 DEFINE mov____%ebp,%ecx 89e9
 DEFINE mov____%ebp,%edx 89ea
+DEFINE mov____%ebx,0x32 891d
+DEFINE mov____%ebx,0x32(%ebp) 899d
+DEFINE mov____%ebx,0x8(%ebp) 895d
+DEFINE mov____%ebx,0x8(%edx) 895a
 DEFINE mov____%ecx,(%eax) 8908
 DEFINE mov____%ecx,(%edx) 890a
+DEFINE mov____%ecx,0x32(%ebp) 898d
+DEFINE mov____%ecx,0x8(%ebp) 894d
 DEFINE mov____%edx,%eax 89d0
 DEFINE mov____%edx,%ebx 89d3
 DEFINE mov____%edx,%ecx 89d1
@@ -106,6 +112,8 @@ DEFINE mov____(%eax),%ecx 8b08
 DEFINE mov____(%edx),%ecx 8b0a
 DEFINE mov____(%edx),%edx 8b12
 DEFINE mov____0x32(%eax),%eax 8b80
+DEFINE mov____0x32(%eax),%ebx 8b98
+DEFINE mov____0x32(%eax),%ecx 8b88
 DEFINE mov____0x32(%ebp),%eax 8b85
 DEFINE mov____0x32(%ebp),%eax 8b85
 DEFINE mov____0x32(%ebp),%ebx 8b9d
@@ -115,6 +123,8 @@ DEFINE mov____0x32(%ebp),%edx 8b95
 DEFINE mov____0x32,%eax a1
 DEFINE mov____0x32,%edx 8b15
 DEFINE mov____0x8(%eax),%eax 8b40
+DEFINE mov____0x8(%eax),%ebx 8b58
+DEFINE mov____0x8(%eax),%ecx 8b48
 DEFINE mov____0x8(%ebp),%eax 8b45
 DEFINE mov____0x8(%ebp),%ebx 8b5d
 DEFINE mov____0x8(%ebp),%ecx 8b4d