diff --git a/clang/lib/CIR/CodeGen/CIRGenBuiltinX86.cpp b/clang/lib/CIR/CodeGen/CIRGenBuiltinX86.cpp
index 1c87e945de846..791c73fc49838 100644
--- a/clang/lib/CIR/CodeGen/CIRGenBuiltinX86.cpp
+++ b/clang/lib/CIR/CodeGen/CIRGenBuiltinX86.cpp
@@ -1831,9 +1831,29 @@ CIRGenFunction::emitX86BuiltinExpr(unsigned builtinID, const CallExpr *expr) {
   case X86::BI__builtin_ia32_vcvtph2ps_mask:
   case X86::BI__builtin_ia32_vcvtph2ps256_mask:
   case X86::BI__builtin_ia32_vcvtph2ps512_mask:
+    cgm.errorNYI(expr->getSourceRange(),
+                 std::string("unimplemented X86 builtin call: ") +
+                     getContext().BuiltinInfo.getName(builtinID));
+    return mlir::Value{};
   case X86::BI__builtin_ia32_cvtneps2bf16_128_mask:
   case X86::BI__builtin_ia32_cvtneps2bf16_256_mask:
-  case X86::BI__builtin_ia32_cvtneps2bf16_512_mask:
+  case X86::BI__builtin_ia32_cvtneps2bf16_512_mask: {
+    mlir::Location loc = getLoc(expr->getExprLoc());
+    cir::VectorType resTy = cast<cir::VectorType>(convertType(expr->getType()));
+    unsigned numElts = resTy.getSize();
+    StringRef intrinsicName;
+    if (builtinID == X86::BI__builtin_ia32_cvtneps2bf16_128_mask)
+      intrinsicName = "x86.avx512bf16.cvtneps2bf16.128";
+    else if (builtinID == X86::BI__builtin_ia32_cvtneps2bf16_256_mask)
+      intrinsicName = "x86.avx512bf16.cvtneps2bf16.256";
+    else
+      intrinsicName = "x86.avx512bf16.cvtneps2bf16.512";
+    mlir::Value selectMask = getMaskVecValue(builder, loc, ops[2], numElts);
+    mlir::Value intrinsicResult = emitIntrinsicCallOp(
+        builder, loc, intrinsicName, resTy, mlir::ValueRange{ops[0]});
+    return emitX86Select(builder, loc, selectMask, intrinsicResult, ops[1]);
+  }
+
   case X86::BI__cpuid:
   case X86::BI__cpuidex:
   case X86::BI__emul:
diff --git a/clang/test/CIR/CodeGenBuiltins/X86/avx512vlbf16-builtins.c b/clang/test/CIR/CodeGenBuiltins/X86/avx512vlbf16-builtins.c
new file mode 100644
index 0000000000000..d312ccbe93807
--- /dev/null
+++ b/clang/test/CIR/CodeGenBuiltins/X86/avx512vlbf16-builtins.c
@@ -0,0 +1,44 @@
+// RUN: %clang_cc1 -flax-vector-conversions=none -ffreestanding %s -triple=x86_64-unknown-linux -target-feature +avx512f -target-feature +avx512vl -target-feature +avx512bf16 -fclangir -emit-cir -o %t.cir -Wall -Werror -Wsign-conversion 
+// RUN: FileCheck --check-prefix=CIR --input-file=%t.cir %s
+// RUN: %clang_cc1 -flax-vector-conversions=none -ffreestanding %s -triple=x86_64-unknown-linux -target-feature +avx512f -target-feature +avx512vl -target-feature +avx512bf16 -fclangir -emit-llvm -o %t.ll -Wall -Werror -Wsign-conversion
+// RUN: FileCheck --check-prefixes=LLVM --input-file=%t.ll %s
+// RUN: %clang_cc1 -flax-vector-conversions=none -ffreestanding %s -triple=x86_64-unknown-linux -target-feature +avx512f -target-feature +avx512vl -target-feature +avx512bf16 -emit-llvm -o %t.ll -Wall -Werror -Wsign-conversion
+// RUN: FileCheck --check-prefixes=OGCG --input-file=%t.ll %s
+
+#include <immintrin.h>
+
+__m256bh test_mm512_mask_cvtneps_pbh(__m256bh src, __mmask16 k, __m512 a) {
+  // CIR-LABEL: @test_mm512_mask_cvtneps_pbh
+  // CIR: cir.call @_mm512_mask_cvtneps_pbh({{.+}}, {{.+}}, {{.+}}) : (!cir.vector<16 x !cir.bf16>, !u16i, !cir.vector<16 x !cir.float>) -> !cir.vector<16 x !cir.bf16>
+
+  // LLVM-LABEL: @test_mm512_mask_cvtneps_pbh
+  // LLVM: call <16 x bfloat> @llvm.x86.avx512bf16.cvtneps2bf16.512
+
+  // OGCG-LABEL: @test_mm512_mask_cvtneps_pbh
+  // OGCG: call <16 x bfloat> @llvm.x86.avx512bf16.cvtneps2bf16.512
+  return _mm512_mask_cvtneps_pbh(src, k, a);
+}
+
+__m128bh test_mm256_mask_cvtneps_pbh(__m128bh src, __mmask8 k, __m256 a) {
+  // CIR-LABEL: test_mm256_mask_cvtneps_pbh
+  // CIR: cir.call @_mm256_mask_cvtneps_pbh({{.+}}, {{.+}}, {{.+}}) : (!cir.vector<8 x !cir.bf16>, !u8i, !cir.vector<8 x !cir.float>) -> !cir.vector<8 x !cir.bf16>
+  
+  // LLVM-LABEL: test_mm256_mask_cvtneps_pbh
+  // LLVM: call <8 x bfloat> @llvm.x86.avx512bf16.cvtneps2bf16.256(<8 x float> {{.+}})
+
+  // OGCG-LABEL: test_mm256_mask_cvtneps_pbh
+  // OGCG: call <8 x bfloat> @llvm.x86.avx512bf16.cvtneps2bf16.256(<8 x float> {{.+}})  
+  return _mm256_mask_cvtneps_pbh(src, k, a);
+}
+
+__m128bh test_mm_mask_cvtneps_pbh(__m128bh src, __mmask8 k, __m128 a) {
+  // CIR-LABEL: test_mm_mask_cvtneps_pbh
+  // CIR: cir.call @_mm_mask_cvtneps_pbh({{.+}}, {{.+}}, {{.+}}) : (!cir.vector<8 x !cir.bf16>, !u8i, !cir.vector<4 x !cir.float>) -> !cir.vector<8 x !cir.bf1{{.+}}
+
+  // LLVM-LABEL: test_mm_mask_cvtneps_pbh
+  // LLVM: call <8 x bfloat> @llvm.x86.avx512bf16.mask.cvtneps2bf16.128(<4 x float> {{.+}}, <8 x bfloat> {{.+}}, <4 x i1> %extract.i)
+
+  // OGCG-LABEL: test_mm_mask_cvtneps_pbh
+  // OGCG: call <8 x bfloat> @llvm.x86.avx512bf16.mask.cvtneps2bf16.128(<4 x float> {{.+}}, <8 x bfloat> {{.+}}, <4 x i1> %extract.i)
+  return _mm_mask_cvtneps_pbh(src, k, a);
+}