[X86][AVX512FP16] Decouple AVX512VL and AVX512DQ from AVX512FP16

Fixes: #136209

Author: phoebewang

clang/lib/Headers/avx512fp16intrin.h

@@ -553,7 +553,8 @@ static __inline__ __m512h __DEFAULT_FN_ATTRS512 _mm512_abs_ph(__m512h __A) {
 }
 
 static __inline__ __m512h __DEFAULT_FN_ATTRS512 _mm512_conj_pch(__m512h __A) {
-  return (__m512h)_mm512_xor_ps((__m512)__A, _mm512_set1_ps(-0.0f));
+  return (__m512h)_mm512_xor_epi32((__m512i)__A,
+                                   _mm512_set1_epi32(-2147483648));
 }
 
 static __inline__ __m512h __DEFAULT_FN_ATTRS512

clang/test/CodeGen/X86/avx512fp16-builtins-constrained-cmp.c

@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 -flax-vector-conversions=none -ffreestanding %s -triple=x86_64-apple-darwin -target-feature +avx512fp16 -emit-llvm -ffp-exception-behavior=strict -o - -Wall -Werror | FileCheck %s
+// RUN: %clang_cc1 -flax-vector-conversions=none -ffreestanding %s -triple=x86_64-apple-darwin -target-feature +avx512fp16 -target-feature +avx512vl -emit-llvm -ffp-exception-behavior=strict -o - -Wall -Werror | FileCheck %s
 
 #include <immintrin.h>