From 3c1b33b7d57ad8b8aeeab8babd48625b86532e0b Mon Sep 17 00:00:00 2001
From: Felix Fietkau <nbd@nbd.name>
Date: Thu, 7 Jun 2018 15:18:51 +0200
Subject: [PATCH] utils: add const_* byteswapping functions

Some gcc versions have issues with the __builtin_choose_expr construct
which attempts to automatically use the const versions of those
functions.

Make it possible to explicitly use const_* versions to avoid that.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
---
 utils.h | 32 ++++++++++++++++++++++++++++++++
 1 file changed, 32 insertions(+)

diff --git a/utils.h b/utils.h
index 019d817..27f81e5 100644
--- a/utils.h
+++ b/utils.h
@@ -142,6 +142,22 @@ int clock_gettime(int type, struct timespec *tv);
 
 #if __BYTE_ORDER == __LITTLE_ENDIAN
 
+#define const_cpu_to_be64(x) __constant_swap64(x)
+#define const_cpu_to_be32(x) __constant_swap32(x)
+#define const_cpu_to_be16(x) __constant_swap16(x)
+
+#define const_be64_to_cpu(x) __constant_swap64(x)
+#define const_be32_to_cpu(x) __constant_swap32(x)
+#define const_be16_to_cpu(x) __constant_swap16(x)
+
+#define const_cpu_to_le64(x) (x)
+#define const_cpu_to_le32(x) (x)
+#define const_cpu_to_le16(x) (x)
+
+#define const_le64_to_cpu(x) (x)
+#define const_le32_to_cpu(x) (x)
+#define const_le16_to_cpu(x) (x)
+
 #define cpu_to_be64(x) __eval_safe(__constant_swap64, x)
 #define cpu_to_be32(x) __eval_safe(__constant_swap32, x)
 #define cpu_to_be16(x) __eval_safe(__constant_swap16, x)
@@ -160,6 +176,22 @@ int clock_gettime(int type, struct timespec *tv);
 
 #else /* __BYTE_ORDER == __LITTLE_ENDIAN */
 
+#define const_cpu_to_le64(x) __constant_swap64(x)
+#define const_cpu_to_le32(x) __constant_swap32(x)
+#define const_cpu_to_le16(x) __constant_swap16(x)
+
+#define const_le64_to_cpu(x) __constant_swap64(x)
+#define const_le32_to_cpu(x) __constant_swap32(x)
+#define const_le16_to_cpu(x) __constant_swap16(x)
+
+#define const_cpu_to_be64(x) (x)
+#define const_cpu_to_be32(x) (x)
+#define const_cpu_to_be16(x) (x)
+
+#define const_be64_to_cpu(x) (x)
+#define const_be32_to_cpu(x) (x)
+#define const_be16_to_cpu(x) (x)
+
 #define cpu_to_le64(x) __eval_safe(__constant_swap64, x)
 #define cpu_to_le32(x) __eval_safe(__constant_swap32, x)
 #define cpu_to_le16(x) __eval_safe(__constant_swap16, x)
-- 
2.25.1