From 4ca60174520d321a19183e6c5d8f829b7c7d1e4e Mon Sep 17 00:00:00 2001
From: Vincent St-Amour <stamourv@iro.umontreal.ca>
Date: Fri, 27 Feb 2009 12:06:07 -0500
Subject: [PATCH] Added bitwise ior and xor for bignums.

---
 bignums.c    | 43 +++++++++++++++++++++++--------------------
 primitives.c |  6 +++++-
 2 files changed, 28 insertions(+), 21 deletions(-)

diff --git a/bignums.c b/bignums.c
index 8c5ff8f..1d81be2 100644
--- a/bignums.c
+++ b/bignums.c
@@ -8,13 +8,7 @@
 
 #ifdef INFINITE_PRECISION_BIGNUMS
 
-// TODO clean up all this
-
 integer make_integer (digit lo, integer hi) {
-/*   if(!hi && lo <= MAX_FIXNUM && lo >= MIN_FIXNUM) */
-/*     return ENCODE_FIXNUM(lo);o */
-  // TODO won't work, and the bignum functions are unaware of fixnums
-  // TODO if I uncomment, segfaults every time this is called. no ill effect is noticed without it, but kept just in case
   return alloc_ram_cell_init (BIGNUM_FIELD0 | (hi >> 8), hi, lo >> 8, lo);
 }
 
@@ -388,26 +382,35 @@ integer divnonneg (integer x, integer y) {
 integer bitwise_ior (integer x, integer y) {
   /* returns the bitwise inclusive or of x and y */
 
-  obj result = ZERO;
-  printf("START\n");
+  obj result = NIL;
   
   for (;;){
-    printf("LOOP\n");
-    if (obj_eq(x, ZERO)){
-      printf("ZERO\n");
-      return make_integer(y, result);
-    }
-    if (obj_eq(x, NEG1)){
-      printf("NEG1\n");
-      return norm(x, result);
-    }
-    result = make_integer(integer_lo(x) | integer_lo(y), // TODO a l'envers
+    if (obj_eq(x, ZERO))
+      return norm(result, y);
+    if (obj_eq(x, NEG1))
+      return norm(result, x);
+    result = make_integer(integer_lo(x) | integer_lo(y),
+			  result);
+    x = integer_hi(x);
+    y = integer_hi(y);
+  }
+}
+
+integer bitwise_xor (integer x, integer y) { // TODO similar to ior (only diff is the test), abstract ?
+  /* returns the bitwise inclusive or of x and y */
+  
+  obj result = NIL;
+  
+  for (;;){
+    if (obj_eq(x, ZERO))
+      return norm(result, y);
+    if (obj_eq(x, NEG1))
+      return norm(result, x);
+    result = make_integer(integer_lo(x) ^ integer_lo(y),
 			  result);
     x = integer_hi(x);
     y = integer_hi(y);
-    printf("END-LOOP\n");
   }
-  // TODO test for fixnums
 }
 
 // used only in primitives that use small numbers only
diff --git a/primitives.c b/primitives.c
index f15c4c9..8efb243 100644
--- a/primitives.c
+++ b/primitives.c
@@ -234,7 +234,7 @@ void prim_geq (void) {
   arg2 = OBJ_FALSE;
 }
 
-void prim_ior (void) { // TODO FOOBIGNUMS these have not been implemented with bignums, do it
+void prim_ior (void) {
 #ifdef INFINITE_PRECISION_BIGNUMS
   arg1 = bitwise_ior(arg1, arg2);
 #else
@@ -245,8 +245,12 @@ void prim_ior (void) { // TODO FOOBIGNUMS these have not been implemented with b
 }
 
 void prim_xor (void) {
+#ifdef INFINITE_PRECISION_BIGNUMS
+  arg1 = bitwise_xor(arg1, arg2);
+#else
   decode_2_int_args (); // TODO is the function call overhead worth it ?
   arg1 = encode_int (a1 ^ a2);
+#endif
   arg2 = OBJ_FALSE;
 }
 
-- 
2.11.4.GIT