| //! Run-time feature detection for PowerPC on Linux. |
| |
| use super::auxvec; |
| use crate::detect::{cache, Feature}; |
| |
| /// Try to read the features from the auxiliary vector, and if that fails, try |
| /// to read them from /proc/cpuinfo. |
| pub(crate) fn detect_features() -> cache::Initializer { |
| let mut value = cache::Initializer::default(); |
| let enable_feature = |value: &mut cache::Initializer, f, enable| { |
| if enable { |
| value.set(f as u32); |
| } |
| }; |
| |
| // The values are part of the platform-specific [asm/cputable.h][cputable] |
| // |
| // [cputable]: https://github.com/torvalds/linux/blob/master/arch/powerpc/include/uapi/asm/cputable.h |
| if let Ok(auxv) = auxvec::auxv() { |
| // note: the PowerPC values are the mask to do the test (instead of the |
| // index of the bit to test like in ARM and Aarch64) |
| enable_feature(&mut value, Feature::altivec, auxv.hwcap & 0x10000000 != 0); |
| enable_feature(&mut value, Feature::vsx, auxv.hwcap & 0x00000080 != 0); |
| enable_feature(&mut value, Feature::power8, auxv.hwcap2 & 0x80000000 != 0); |
| return value; |
| } |
| |
| // PowerPC's /proc/cpuinfo lacks a proper Feature field, |
| // but `altivec` support is indicated in the `cpu` field. |
| #[cfg(feature = "std_detect_file_io")] |
| if let Ok(c) = super::cpuinfo::CpuInfo::new() { |
| enable_feature(&mut value, Feature::altivec, c.field("cpu").has("altivec")); |
| return value; |
| } |
| value |
| } |
