Let's see.

Author: dvanhorn

langs/mug/compile-ops.rkt

@@ -142,13 +142,16 @@
        (Add rdx 1)              ; #words = 1 + (len+1)/2
        (Sar rdx 1)
        (Add rdx 1)
-       (Sal rdx 3)              ; #bytes = 8*#words
-       (Mov r15 rbx)            ; save what will be rax in non-volatile register
-       (Add rbx rdx)            ; increment before rdx is destroyed
+       (Sal rdx 3)              ; #bytes = 8*#words       
+
+       (Mov 'r12 rdx)            ; save rdx before destroyed
        pad-stack
-       (Call 'memcpy)
+       (Call 'my_memcpy)
        unpad-stack
-       (Mov rax r15)))
+       (Mov rbx rax) ; dst is returned, install as heap pointer
+       (Add rbx 'r12)))
+       
+            
 
 ;; Op2 -> Asm
 (define (compile-op2 p)

langs/mug/compile.rkt

@@ -44,4 +44,4 @@
        (Extern 'write_byte)
        (Extern 'raise_error)
        (Extern 'intern_symbol)
-       (Extern 'memcpy)))
+       (Extern 'my_memcpy)))

langs/mug/symbol.c

@@ -1,4 +1,7 @@
 #include <stdlib.h>
+#include <inttypes.h>
+#include <stdio.h>
+#include <string.h>
 #include "values.h"
 
 int symb_cmp(const val_symb_t *, const val_symb_t *);
@@ -12,6 +15,13 @@ struct Node {
 
 static struct Node *symbol_tbl = NULL;
 
+void *my_memcpy(void *dest, const void *src, size_t n) {
+  printf("memcpy(%" PRId64 ", %" PRId64 ", %" PRId64 ")", (int64_t)dest, (int64_t)src, (int64_t)n);
+  void * r = memcpy(dest, src, n);
+  printf(" = %" PRId64 "\n", (int64_t)r);
+  return r;
+}
+
 val_symb_t *intern_symbol(val_symb_t* symb)
 {
   struct Node **curr = &symbol_tbl;