1 files changed, 47 insertions, 0 deletions
diff --git a/js/src/jit-test/tests/warp/min-max-foldsTo-1.js b/js/src/jit-test/tests/warp/min-max-foldsTo-1.js
new file mode 100644
index 0000000000..accc6ea416
--- /dev/null
+++ b/js/src/jit-test/tests/warp/min-max-foldsTo-1.js
@@ -0,0 +1,47 @@
+with ({}); // Don't inline anything into the top-level script.
+
+function args() { return arguments; }
+
+for (let xs of [
+  // Array
+  [[], [1, 2, 3]],
+
+  // String
+  ["", "asdf"],
+
+  // ArrayBufferView
+  [new Int32Array(0), new Int32Array(10)],
+
+  // Arguments
+  [args(), args(1, 2, 3)],
+]) {
+  for (let cst of [0, -1]) {
+    // Fold `Math.min(length ≥ 0, constant ≤ 0)` to `constant`.
+    let min = Function("x", `return Math.min(x.length, ${cst})`);
+    for (let i = 0; i < 100; ++i) {
+      let x = xs[i & 1];
+      assertEq(min(x), cst);
+    }
+
+    // Reverse operands.
+    min = Function("x", `return Math.min(${cst}, x.length)`);
+    for (let i = 0; i < 100; ++i) {
+      let x = xs[i & 1];
+      assertEq(min(x), cst);
+    }
+
+    // Fold `Math.max(length ≥ 0, constant ≤ 0)` to `length`.
+    let max = Function("x", `return Math.max(x.length, ${cst})`);
+    for (let i = 0; i < 100; ++i) {
+      let x = xs[i & 1];
+      assertEq(max(x), x.length);
+    }
+
+    // Reverse operands.
+    max = Function("x", `return Math.max(${cst}, x.length)`);
+    for (let i = 0; i < 100; ++i) {
+      let x = xs[i & 1];
+      assertEq(max(x), x.length);
+    }
+  }
+}