From 01fe03877fa9539008263453bf25c248a50ca427 Mon Sep 17 00:00:00 2001
From: Jeff Muizelaar <jmuizelaar@mozilla.com>
Date: Tue, 5 Mar 2024 03:12:28 +0000
Subject: [PATCH] Bug 1882291. Switch to stdarch_arm_neon_intrinsics feature on
 rust >=1.78. r=glandium

We only need this on ARM32 because the ARM64 intrinsics are stable.

stdarch_arm_neon_intrinsics was split out from stdsimd here:
https://github.com/rust-lang/stdarch/pull/1486

Differential Revision: https://phabricator.services.mozilla.com/D203039
---
 Cargo.lock          | 1 +
 gfx/qcms/Cargo.toml | 3 +++
 gfx/qcms/build.rs   | 7 +++++++
 gfx/qcms/src/lib.rs | 6 ++++--
 4 files changed, 15 insertions(+), 2 deletions(-)
 create mode 100644 gfx/qcms/build.rs

diff --git a/Cargo.lock b/Cargo.lock
index a55b3e6dc37ab..23601ec89b6d7 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -4274,6 +4274,7 @@ name = "qcms"
 version = "0.2.0"
 dependencies = [
  "libc",
+ "version_check",
 ]
 
 [[package]]
diff --git a/gfx/qcms/Cargo.toml b/gfx/qcms/Cargo.toml
index e976054a7b32a..f50d6623a1b4e 100644
--- a/gfx/qcms/Cargo.toml
+++ b/gfx/qcms/Cargo.toml
@@ -20,3 +20,6 @@ cmyk = []
 
 [dependencies]
 libc = {version = "0.2", optional = true }
+
+[build-dependencies]
+version_check = "0.9"
diff --git a/gfx/qcms/build.rs b/gfx/qcms/build.rs
new file mode 100644
index 0000000000000..6810a8828edeb
--- /dev/null
+++ b/gfx/qcms/build.rs
@@ -0,0 +1,7 @@
+extern crate version_check as rustc;
+
+fn main() {
+    if rustc::is_min_version("1.78.0").unwrap_or(false) {
+        println!("cargo:rustc-cfg=stdsimd_split");
+    }
+}
diff --git a/gfx/qcms/src/lib.rs b/gfx/qcms/src/lib.rs
index c311964ee3f49..fc496816a8bfc 100644
--- a/gfx/qcms/src/lib.rs
+++ b/gfx/qcms/src/lib.rs
@@ -7,9 +7,11 @@
 #![allow(non_upper_case_globals)]
 // These are needed for the neon SIMD code and can be removed once the MSRV supports the
 // instrinsics we use
-#![cfg_attr(feature = "neon", feature(stdsimd))]
+#![cfg_attr(all(stdsimd_split, target_arch = "arm", feature = "neon"), feature(stdarch_arm_neon_intrinsics))]
+#![cfg_attr(all(stdsimd_split, target_arch = "arm", feature = "neon"), feature(stdarch_arm_feature_detection))]
+#![cfg_attr(all(not(stdsimd_split), target_arch = "arm", feature = "neon"), feature(stdsimd))]
 #![cfg_attr(
-    feature = "neon",
+    all(target_arch = "arm", feature = "neon"),
     feature(arm_target_feature, raw_ref_op)
 
 )]