[Bug d/96429] d: Pointer subtraction uses TRUNC_DIV_EXPR

[ibuclaw at gdcproject dot org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96429

--- Comment #1 from Iain Buclaw <ibuclaw at gdcproject dot org> ---
--- a/gcc/d/expr.cc
+++ b/gcc/d/expr.cc
@@ -620,6 +620,18 @@ public:
        break;

       case TOKdiv:
+       /* Determine if the div expression is a lowered pointer diff operation.
+          The front-end rewrites `(p1 - p2)' into `(p1 - p2) / stride'.  */
+       if (MinExp *me = e->e1->isMinExp ())
+         {
+           if (me->e1->type->ty == Tpointer && me->e2->type->ty == Tpointer
+               && e->e2->op == TOKint64)
+             {
+               code = EXACT_DIV_EXPR;
+               break;
+             }
+         }
+
        code = e->e1->type->isintegral ()
          ? TRUNC_DIV_EXPR : RDIV_EXPR;
        break;