Polynomial types are signed on ARM

Author: Amanieu

crates/core_arch/src/arm_shared/neon/mod.rs

@@ -11,10 +11,25 @@ use crate::{
 #[cfg(test)]
 use stdarch_test::assert_instr;
 
+// Polynomial types are signed on ARM and unsigned on AArch64. However the
+// situation for poly64_t on ARM is less clear: it is signed in Clang but
+// unsigned in GCC. We follow Clang here for now.
+#[cfg(target_arch = "aarch64")]
 pub(crate) type p8 = u8;
+#[cfg(target_arch = "aarch64")]
 pub(crate) type p16 = u16;
+#[cfg(target_arch = "aarch64")]
 pub(crate) type p64 = u64;
+#[cfg(target_arch = "aarch64")]
 pub(crate) type p128 = u128;
+#[cfg(target_arch = "arm")]
+pub(crate) type p8 = i8;
+#[cfg(target_arch = "arm")]
+pub(crate) type p16 = i16;
+#[cfg(target_arch = "arm")]
+pub(crate) type p64 = i64;
+#[cfg(target_arch = "arm")]
+pub(crate) type p128 = i128;
 
 types! {
     /// ARM-specific 64-bit wide vector of eight packed `i8`.