From: =?utf-8?q?Fabian_Gr=C3=BCnbichler?= <git@fabian.gruenbichler.email>
Date: Tue, 22 Jul 2025 09:55:13 +0200
Subject: tests: fix autovectorization bswaps test
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Debian's s390x baseline is too low for this test to work reliably, but we do
want it to run on x86_64 and aarch64.

(cherry picked from commit 59069986e7446123556630a32adce7f101eeaf8d)
(cherry picked from commit 6b0deb2161b730be16c1ec13c1ab47455c054f37)

with some additional changes on top


Signed-off-by: Fabian Grünbichler <git@fabian.gruenbichler.email>
---
 tests/codegen/autovec/dont-shuffle-bswaps-opt2.rs | 31 ++++++++++++++++++
 tests/codegen/autovec/dont-shuffle-bswaps-opt3.rs | 40 +++++++++++++++++++++++
 tests/codegen/dont-shuffle-bswaps.rs              | 38 ---------------------
 3 files changed, 71 insertions(+), 38 deletions(-)
 create mode 100644 tests/codegen/autovec/dont-shuffle-bswaps-opt2.rs
 create mode 100644 tests/codegen/autovec/dont-shuffle-bswaps-opt3.rs
 delete mode 100644 tests/codegen/dont-shuffle-bswaps.rs

diff --git a/tests/codegen/autovec/dont-shuffle-bswaps-opt2.rs b/tests/codegen/autovec/dont-shuffle-bswaps-opt2.rs
new file mode 100644
index 0000000..c354228
--- /dev/null
+++ b/tests/codegen/autovec/dont-shuffle-bswaps-opt2.rs
@@ -0,0 +1,31 @@
+//@ compile-flags: -Copt-level=2
+
+#![crate_type = "lib"]
+#![no_std]
+
+// This test is paired with the arch-specific -opt3.rs test.
+
+// The code is from https://github.com/rust-lang/rust/issues/122805.
+// Ensure we do not generate the shufflevector instruction
+// to avoid complicating the code.
+
+// CHECK-LABEL: define{{.*}}void @convert(
+// CHECK-NOT: shufflevector
+#[no_mangle]
+pub fn convert(value: [u16; 8]) -> [u8; 16] {
+    #[cfg(target_endian = "little")]
+    let bswap = u16::to_be;
+    #[cfg(target_endian = "big")]
+    let bswap = u16::to_le;
+    let addr16 = [
+        bswap(value[0]),
+        bswap(value[1]),
+        bswap(value[2]),
+        bswap(value[3]),
+        bswap(value[4]),
+        bswap(value[5]),
+        bswap(value[6]),
+        bswap(value[7]),
+    ];
+    unsafe { core::mem::transmute::<_, [u8; 16]>(addr16) }
+}
diff --git a/tests/codegen/autovec/dont-shuffle-bswaps-opt3.rs b/tests/codegen/autovec/dont-shuffle-bswaps-opt3.rs
new file mode 100644
index 0000000..b92b362
--- /dev/null
+++ b/tests/codegen/autovec/dont-shuffle-bswaps-opt3.rs
@@ -0,0 +1,40 @@
+//@ revisions: AARCH64 X86_64
+//@ compile-flags: -Copt-level=3
+//@[AARCH64] only-aarch64
+//@[X86_64] only-x86_64
+
+#![crate_type = "lib"]
+#![no_std]
+
+// This test is paired with the arch-neutral -opt2.rs test
+
+// The code is from https://github.com/rust-lang/rust/issues/122805.
+// Ensure we do not generate the shufflevector instruction
+// to avoid complicating the code.
+
+// CHECK-LABEL: define{{.*}}void @convert(
+// CHECK-NOT: shufflevector
+
+// On higher opt levels, this should just be a bswap:
+// CHECK: load <8 x i16>
+// CHECK-NEXT: call <8 x i16> @llvm.bswap
+// CHECK-NEXT: store <8 x i16>
+// CHECK-NEXT: ret void
+#[no_mangle]
+pub fn convert(value: [u16; 8]) -> [u8; 16] {
+    #[cfg(target_endian = "little")]
+    let bswap = u16::to_be;
+    #[cfg(target_endian = "big")]
+    let bswap = u16::to_le;
+    let addr16 = [
+        bswap(value[0]),
+        bswap(value[1]),
+        bswap(value[2]),
+        bswap(value[3]),
+        bswap(value[4]),
+        bswap(value[5]),
+        bswap(value[6]),
+        bswap(value[7]),
+    ];
+    unsafe { core::mem::transmute::<_, [u8; 16]>(addr16) }
+}
diff --git a/tests/codegen/dont-shuffle-bswaps.rs b/tests/codegen/dont-shuffle-bswaps.rs
deleted file mode 100644
index 0e712bc..0000000
--- a/tests/codegen/dont-shuffle-bswaps.rs
+++ /dev/null
@@ -1,38 +0,0 @@
-//@ revisions: OPT2 OPT3
-//@[OPT2] compile-flags: -Copt-level=2
-//@[OPT3] compile-flags: -C opt-level=3
-// some targets don't do the opt we are looking for
-//@[OPT3] only-64bit
-//@ min-llvm-version: 18.1.3
-
-#![crate_type = "lib"]
-#![no_std]
-
-// The code is from https://github.com/rust-lang/rust/issues/122805.
-// Ensure we do not generate the shufflevector instruction
-// to avoid complicating the code.
-// CHECK-LABEL: define{{.*}}void @convert(
-// CHECK-NOT: shufflevector
-// On higher opt levels, this should just be a bswap:
-// OPT3: load <8 x i16>
-// OPT3-NEXT: call <8 x i16> @llvm.bswap
-// OPT3-NEXT: store <8 x i16>
-// OPT3-NEXT: ret void
-#[no_mangle]
-pub fn convert(value: [u16; 8]) -> [u8; 16] {
-    #[cfg(target_endian = "little")]
-    let bswap = u16::to_be;
-    #[cfg(target_endian = "big")]
-    let bswap = u16::to_le;
-    let addr16 = [
-        bswap(value[0]),
-        bswap(value[1]),
-        bswap(value[2]),
-        bswap(value[3]),
-        bswap(value[4]),
-        bswap(value[5]),
-        bswap(value[6]),
-        bswap(value[7]),
-    ];
-    unsafe { core::mem::transmute::<_, [u8; 16]>(addr16) }
-}