add avx512fp16 to x86 target features

Author: usamoi

compiler/rustc_codegen_gcc/src/lib.rs

@@ -408,7 +408,7 @@ pub fn target_features(sess: &Session, allow_unstable: bool, target_info: &Locke
         .filter(|_feature| {
             target_info.cpu_supports(_feature)
             /*
-               adx, aes, avx, avx2, avx512bf16, avx512bitalg, avx512bw, avx512cd, avx512dq, avx512er, avx512f, avx512ifma,
+               adx, aes, avx, avx2, avx512bf16, avx512bitalg, avx512bw, avx512cd, avx512dq, avx512er, avx512f, avx512fp16, avx512ifma,
                avx512pf, avx512vbmi, avx512vbmi2, avx512vl, avx512vnni, avx512vp2intersect, avx512vpopcntdq,
                bmi1, bmi2, cmpxchg16b, ermsb, f16c, fma, fxsr, gfni, lzcnt, movbe, pclmulqdq, popcnt, rdrand, rdseed, rtm,
                sha, sse, sse2, sse3, sse4.1, sse4.2, sse4a, ssse3, tbm, vaes, vpclmulqdq, xsave, xsavec, xsaveopt, xsaves

compiler/rustc_target/src/target_features.rs

@@ -201,6 +201,7 @@ const X86_ALLOWED_FEATURES: &[(&str, Stability)] = &[
     ("avx512dq", Unstable(sym::avx512_target_feature)),
     ("avx512er", Unstable(sym::avx512_target_feature)),
     ("avx512f", Unstable(sym::avx512_target_feature)),
+    ("avx512fp16", Unstable(sym::avx512_target_feature)),
     ("avx512ifma", Unstable(sym::avx512_target_feature)),
     ("avx512pf", Unstable(sym::avx512_target_feature)),
     ("avx512vbmi", Unstable(sym::avx512_target_feature)),