Add build system scaffolding and libc headers

1 files changed, 36 insertions, 0 deletions

diff --git a/include/arch/x86_64/asm/swab.h b/include/arch/x86_64/asm/swab.h
new file mode 100644
index 00000000..0324f00d
--- /dev/null
+++ b/include/arch/x86_64/asm/swab.h
@@ -0,0 +1,36 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+#ifndef _ASM_X86_SWAB_H
+#define _ASM_X86_SWAB_H
+
+#include <linux/types.h>
+
+static __inline__ __u32 __arch_swab32(__u32 val)
+{
+	__asm__("bswapl %0" : "=r"(val) : "0"(val));
+	return val;
+}
+#define __arch_swab32 __arch_swab32
+
+static __inline__ __u64 __arch_swab64(__u64 val)
+{
+#ifdef __i386__
+	union {
+		struct {
+			__u32 a;
+			__u32 b;
+		} s;
+		__u64 u;
+	} v;
+	v.u = val;
+	__asm__("bswapl %0 ; bswapl %1 ; xchgl %0,%1"
+		: "=r"(v.s.a), "=r"(v.s.b)
+		: "0"(v.s.a), "1"(v.s.b));
+	return v.u;
+#else /* __i386__ */
+	__asm__("bswapq %0" : "=r"(val) : "0"(val));
+	return val;
+#endif
+}
+#define __arch_swab64 __arch_swab64
+
+#endif /* _ASM_X86_SWAB_H */