Auto merge of #69450 - cuviper:llvm-scev-no-wrap, r=nikic

Cherry-pick the LLVM fix for #69225

An additional reproducer was provided in #69225 -- the new testcase here -- which still crashes even after #69241 reverted #67174. Now this pull request updates LLVM with the cherry-picked reversion of its own. This is also going to stable in #69444.

I have not tried to reapply #67174 yet -- cc @kraai @shahn

Author: bors

src/llvm-project

@@ -0,0 +1,33 @@
+// run-fail
+// compile-flags: -C opt-level=3
+// error-pattern: index out of bounds: the len is 0 but the index is 16777216
+// ignore-wasm no panic or subprocess support
+// ignore-emscripten no panic or subprocess support
+
+fn do_test(x: usize) {
+    let mut arr = vec![vec![0u8; 3]];
+
+    let mut z = vec![0];
+    for arr_ref in arr.iter_mut() {
+        for y in 0..x {
+            for _ in 0..1 {
+                z.reserve_exact(x);
+                let iterator = std::iter::repeat(0).take(x);
+                let mut cnt = 0;
+                iterator.for_each(|_| {
+                    z[0] = 0;
+                    cnt += 1;
+                });
+                let a = y * x;
+                let b = (y + 1) * x - 1;
+                let slice = &mut arr_ref[a..b];
+                slice[1 << 24] += 1;
+            }
+        }
+    }
+}
+
+fn main() {
+    do_test(1);
+    do_test(2);
+}