Ported add_int64 and sub_int64 to jai.

2 files changed, 62 insertions, 27 deletions

diff --git a/ttt.jai b/ttt.jai
index fd39bb3..ea999c8 100644
--- a/ttt.jai
+++ b/ttt.jai
@@ -271,39 +271,23 @@ int mvprintw_time(int y, int x, intmax_t time, int space) {
         return mvprintw(y, x, "%*s  ∞  %*s", left_padding, "", right_padding, "");
     }
 }
+*/
 
-int64_t add_int64(int64_t x, int64_t y) {
-    int64_t result;
-#ifdef __GNUC__
-    bool overflow = __builtin_add_overflow(x, y, &result);
-    if (overflow) {
-        result = ((uint64_t)x >> 63) + INT64_MAX; // Equivalent to (x > 0 ? INT64_MAX : INT64_MIN)
-    }
-#else
-    result =
-        (y > 0 && x > INT64_MAX - y) ? INT64_MAX :
-        (y < 0 && x < INT64_MIN - y) ? INT64_MIN :
+add_int64 :: (x :s64, y: s64) -> s64 {
+    return
+        ifx (y > 0 && x > S64_MAX - y) then S64_MAX else
+        ifx (y < 0 && x < S64_MIN - y) then S64_MIN else
         x + y;
-#endif
-    return result;
 }
 
-int64_t sub_int64(int64_t x, int64_t y) {
-    int64_t result;
-#ifdef __GNUC__
-    bool overflow = __builtin_sub_overflow(x, y, &result);
-    if (overflow) {
-        result = ((uint64_t)x >> 63) + INT64_MAX; // Equivalent to (x > 0 ? INT64_MAX : INT64_MIN)
-    }
-#else
-    result =
-        (y < 0 && x > INT64_MAX + y) ? INT64_MAX :
-        (y > 0 && x < INT64_MIN + y) ? INT64_MIN :
+sub_int64 :: (x :s64, y :s64) -> s64 {
+    return
+        ifx (y < 0 && x > S64_MAX + y) then S64_MAX else
+        ifx (y > 0 && x < S64_MIN + y) then S64_MIN else
         x - y;
-#endif
-    return result;
 }
 
+/*
 // Returns active task or NULL if none applies.
 task_st *get_active_task(database_st *db) {
     assert(db != NULL);
@@ -1823,7 +1807,8 @@ int main(int argc, char *argv[]) {
 
 #import "Basic";
 #import "System";
-#import "File_Utilities";
+#import "Math";
+// #import "File_Utilities";
 
 homie : string;
 
diff --git a/unused.jai b/unused.jai
new file mode 100644
index 0000000..3529a46
--- /dev/null
+++ b/unused.jai
@@ -0,0 +1,50 @@
+checked_add :: (a: $T, b: T) -> result: T, overflow: bool 
+#modify {
+    if T.type == .INTEGER return;
+    T = null;
+}
+{
+    overflow: bool;
+    result: T = a + b;
+
+    info := type_info(T);
+    if info.signed {
+        // (+A) + (+B) = −C
+        // (−A) + (−B) = +C
+        if ((a > 0) && (b > 0) && (result < 0)) || ((a < 0) && (b < 0) && (result > 0)) {
+            overflow = true;
+        }
+    } else {
+        if result < a {
+            overflow = true;
+        }
+    }
+
+    return result, overflow;
+}
+
+checked_sub :: (a: $T, b: T) -> result: T, overflow: bool 
+#modify {
+    if T.type == .INTEGER return;
+    T = null;
+}
+{
+    overflow: bool;
+    result: T = a - b;
+
+    info := type_info(T);
+    if info.signed {
+        // (+A) − (−B) = −C
+        // (−A) − (+B) = +C
+        if ((a > 0) && (b < 0) && (result < 0)) || ((a < 0) && (b > 0) && (result > 0)) {
+            overflow = true;
+        }
+    } else {
+        if result > a {
+            overflow = true;
+        }
+    }
+
+    return result, overflow;
+}
+