Liveness: fix branch operands becoming aliased

1 files changed, 33 insertions, 0 deletions

diff --git a/test/behavior/if.zig b/test/behavior/if.zig
index c4dfd04f71..bef02fd1ce 100644
--- a/test/behavior/if.zig
+++ b/test/behavior/if.zig
@@ -167,3 +167,36 @@ test "if-@as-if chain" {
 
     try expect(num_frames == 4);
 }
+
+fn returnTrue() bool {
+    return true;
+}
+
+test "if value shouldn't be load-elided if used later (structs)" {
+    const Foo = struct { x: i32 };
+
+    var a = Foo{ .x = 1 };
+    var b = Foo{ .x = 1 };
+
+    const c = if (@call(.never_inline, returnTrue, .{})) a else b;
+    // The second variable is superfluous with the current
+    // state of codegen optimizations, but in future
+    // "if (smthg) a else a" may be optimized simply into "a".
+
+    a.x = 2;
+    b.x = 3;
+
+    try std.testing.expectEqual(c.x, 1);
+}
+
+test "if value shouldn't be load-elided if used later (optionals)" {
+    var a: ?i32 = 1;
+    var b: ?i32 = 1;
+
+    const c = if (@call(.never_inline, returnTrue, .{})) a else b;
+
+    a = 2;
+    b = 3;
+
+    try std.testing.expectEqual(c, 1);
+}