From 7876b5b8bef1ff8460e48232e68bb5136f04e7b5 Mon Sep 17 00:00:00 2001
From: Eddie Hung <eddie@fpgeh.com>
Date: Fri, 14 Jun 2019 12:40:51 -0700
Subject: [PATCH] Cover __APPLE__ too for little to big endian

---
 backends/aiger/xaiger.cc      | 13 +++++++++----
 frontends/aiger/aigerparse.cc | 11 +++++++----
 2 files changed, 16 insertions(+), 8 deletions(-)

diff --git a/backends/aiger/xaiger.cc b/backends/aiger/xaiger.cc
index 7e22dca7f..7cb311736 100644
--- a/backends/aiger/xaiger.cc
+++ b/backends/aiger/xaiger.cc
@@ -18,6 +18,15 @@
  *
  */
 
+// https://stackoverflow.com/a/46137633
+#ifdef _MSC_VER
+#include <stdlib.h>
+#define __builtin_bswap32 _byteswap_ulong
+#elif defined(__APPLE__)
+#include <libkern/OSByteOrder.h>
+#define __builtin_bswap32 OSSwapInt32
+#endif
+
 #include "kernel/yosys.h"
 #include "kernel/sigtools.h"
 #include "kernel/utils.h"
@@ -27,11 +36,7 @@ PRIVATE_NAMESPACE_BEGIN
 
 inline int32_t to_big_endian(int32_t i32) {
 #if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
-#ifdef _WIN32
-	return _byteswap_ulong(i32);
-#else
 	return __builtin_bswap32(i32);
-#endif
 #elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
 	return i32;
 #else
diff --git a/frontends/aiger/aigerparse.cc b/frontends/aiger/aigerparse.cc
index 7d156fe03..d378a07b7 100644
--- a/frontends/aiger/aigerparse.cc
+++ b/frontends/aiger/aigerparse.cc
@@ -24,7 +24,14 @@
 
 #ifdef _WIN32
 #include <libgen.h>
+#endif
+// https://stackoverflow.com/a/46137633
+#ifdef _MSC_VER
 #include <stdlib.h>
+#define __builtin_bswap32 _byteswap_ulong
+#elif defined(__APPLE__)
+#include <libkern/OSByteOrder.h>
+#define __builtin_bswap32 OSSwapInt32
 #endif
 #include <inttypes.h>
 
@@ -37,11 +44,7 @@ YOSYS_NAMESPACE_BEGIN
 
 inline int32_t from_big_endian(int32_t i32) {
 #if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
-#ifdef _WIN32
-	return _byteswap_ulong(i32);
-#else
 	return __builtin_bswap32(i32);
-#endif
 #elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
 	return i32;
 #else
-- 
2.30.2