1 files changed, 31 insertions, 0 deletions
diff --git a/tests/assembly-llvm/simd/reduce-fadd-unordered.rs b/tests/assembly-llvm/simd/reduce-fadd-unordered.rs
new file mode 100644
index 00000000000..e872826f6ef
--- /dev/null
+++ b/tests/assembly-llvm/simd/reduce-fadd-unordered.rs
@@ -0,0 +1,31 @@
+//@ revisions: x86_64 aarch64
+//@ assembly-output: emit-asm
+//@ compile-flags: --crate-type=lib -Copt-level=3
+
+//@[aarch64] only-aarch64
+//@[x86_64] only-x86_64
+//@[x86_64] compile-flags: -Ctarget-feature=+sse3
+//@ ignore-sgx Test incompatible with LVI mitigations
+#![feature(portable_simd)]
+#![feature(core_intrinsics)]
+use std::intrinsics::simd as intrinsics;
+use std::simd::*;
+// Regression test for https://github.com/rust-lang/rust/issues/130028
+// This intrinsic produces much worse code if you use +0.0 instead of -0.0 because
+// +0.0 isn't as easy to algebraically reassociate, even using LLVM's reassoc attribute!
+// It would emit about an extra fadd, depending on the architecture.
+
+// CHECK-LABEL: reduce_fadd_negative_zero
+pub unsafe fn reduce_fadd_negative_zero(v: f32x4) -> f32 {
+    // x86_64: addps
+    // x86_64-NEXT: movshdup
+    // x86_64-NEXT: addss
+    // x86_64-NOT: xorps
+
+    // aarch64: faddp
+    // aarch64-NEXT: faddp
+
+    // CHECK-NOT: {{f?}}add{{p?s*}}
+    // CHECK: ret
+    intrinsics::simd_reduce_add_unordered(v)
+}