diff --git a/library/stdarch/asm/x86_lzcnt_lzcnt.asm b/library/stdarch/asm/x86_lzcnt_lzcnt.asm
new file mode 100644
index 000000000000..891fb4ee8f5e
--- /dev/null
+++ b/library/stdarch/asm/x86_lzcnt_lzcnt.asm
@@ -0,0 +1,12 @@
+_lzcnt_u32:
+	pushq	%rbp
+	movq	%rsp, %rbp
+	lzcntl	%edi, %eax
+	popq	%rbp
+	retq
+_lzcnt_u64:
+	pushq	%rbp
+	movq	%rsp, %rbp
+	lzcntq	%rdi, %rax
+	popq	%rbp
+	retq
diff --git a/library/stdarch/asm/x86_lzcnt_lzcnt.rs b/library/stdarch/asm/x86_lzcnt_lzcnt.rs
new file mode 100644
index 000000000000..34185009727b
--- /dev/null
+++ b/library/stdarch/asm/x86_lzcnt_lzcnt.rs
@@ -0,0 +1,11 @@
+extern crate stdsimd;
+
+#[no_mangle]
+pub fn lzcnt_u32(x: u32) -> u32 {
+    stdsimd::vendor::_lzcnt_u32(x)
+}
+
+#[no_mangle]
+pub fn lzcnt_u64(x: u64) -> u64 {
+    stdsimd::vendor::_lzcnt_u64(x)
+}
diff --git a/library/stdarch/asm/x86_popcnt_popcnt.asm b/library/stdarch/asm/x86_popcnt_popcnt.asm
new file mode 100644
index 000000000000..ef8fcf211c54
--- /dev/null
+++ b/library/stdarch/asm/x86_popcnt_popcnt.asm
@@ -0,0 +1,12 @@
+_popcnt_u32:
+	pushq	%rbp
+	movq	%rsp, %rbp
+	popcntl	%edi, %eax
+	popq	%rbp
+	retq
+_popcnt_u64:
+	pushq	%rbp
+	movq	%rsp, %rbp
+	popcntq	%rdi, %rax
+	popq	%rbp
+	retq
diff --git a/library/stdarch/asm/x86_popcnt_popcnt.rs b/library/stdarch/asm/x86_popcnt_popcnt.rs
new file mode 100644
index 000000000000..9f215be6b2a3
--- /dev/null
+++ b/library/stdarch/asm/x86_popcnt_popcnt.rs
@@ -0,0 +1,11 @@
+extern crate stdsimd;
+
+#[no_mangle]
+pub fn popcnt_u32(x: u32) -> u32 {
+    stdsimd::vendor::_popcnt32(x)
+}
+
+#[no_mangle]
+pub fn popcnt_u64(x: u64) -> u64 {
+    stdsimd::vendor::_popcnt64(x)
+}