Patrick Georgi submitted this change.
endian: Replace explicit byte swapping with compiler builtin
gcc seems to have some stupid problem with deciding when to inline byte
swapping functions (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92716).
Using the compiler builtin instead seems to solve the problem.
(This doesn't yet solve the issue for the read_be32()-family of
functions, which we should maybe just get rid of at some point?)
Change-Id: Ia2a6d8ea98987266ccc32ffaa0a7f78965fca1cd
Signed-off-by: Julius Werner <jwerner@chromium.org>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/37343
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
---
M payloads/libpayload/include/endian.h
D payloads/libpayload/include/swab.h
M src/include/swab.h
3 files changed, 12 insertions(+), 67 deletions(-)
diff --git a/payloads/libpayload/include/endian.h b/payloads/libpayload/include/endian.h
index ec0825d..dee45f2 100644
--- a/payloads/libpayload/include/endian.h
+++ b/payloads/libpayload/include/endian.h
@@ -34,23 +34,6 @@
#include <arch/types.h>
#include <libpayload-config.h>
-static inline uint16_t swap_bytes16(uint16_t in)
-{
- return ((in & 0xFF) << 8) | ((in & 0xFF00) >> 8);
-}
-
-static inline uint32_t swap_bytes32(uint32_t in)
-{
- return ((in & 0xFF) << 24) | ((in & 0xFF00) << 8) |
- ((in & 0xFF0000) >> 8) | ((in & 0xFF000000) >> 24);
-}
-
-static inline uint64_t swap_bytes64(uint64_t in)
-{
- return ((uint64_t)swap_bytes32((uint32_t)in) << 32) |
- ((uint64_t)swap_bytes32((uint32_t)(in >> 32)));
-}
-
/* Endian functions from glibc 2.9 / BSD "endian.h" */
#if CONFIG(LP_BIG_ENDIAN)
@@ -59,15 +42,15 @@
#define htobe32(in) (in)
#define htobe64(in) (in)
-#define htole16(in) swap_bytes16(in)
-#define htole32(in) swap_bytes32(in)
-#define htole64(in) swap_bytes64(in)
+#define htole16(in) ((uint16_t)__builtin_bswap16(in))
+#define htole32(in) ((uint32_t)__builtin_bswap32(in))
+#define htole64(in) ((uint64_t)__builtin_bswap64(in))
#elif CONFIG(LP_LITTLE_ENDIAN)
-#define htobe16(in) swap_bytes16(in)
-#define htobe32(in) swap_bytes32(in)
-#define htobe64(in) swap_bytes64(in)
+#define htobe16(in) ((uint16_t)__builtin_bswap16(in))
+#define htobe32(in) ((uint32_t)__builtin_bswap32(in))
+#define htobe64(in) ((uint64_t)__builtin_bswap64(in))
#define htole16(in) (in)
#define htole32(in) (in)
diff --git a/payloads/libpayload/include/swab.h b/payloads/libpayload/include/swab.h
deleted file mode 100644
index 2198077..0000000
--- a/payloads/libpayload/include/swab.h
+++ /dev/null
@@ -1,44 +0,0 @@
-#ifndef _SWAB_H
-#define _SWAB_H
-
-/*
- * linux/byteorder/swab.h
- * Byte-swapping, independently from CPU endianness
- * swabXX[ps]?(foo)
- *
- * Francois-Rene Rideau <fare@tunes.org> 19971205
- * separated swab functions from cpu_to_XX,
- * to clean up support for bizarre-endian architectures.
- *
- * See asm-i386/byteorder.h and suches for examples of how to provide
- * architecture-dependent optimized versions
- *
- */
-
-/* casts are necessary for constants, because we never know for sure
- * how U/UL/ULL map to __u16, __u32, __u64. At least not in a portable way.
- */
-#define swab16(x) \
- ((unsigned short)( \
- (((unsigned short)(x) & (unsigned short)0x00ffU) << 8) | \
- (((unsigned short)(x) & (unsigned short)0xff00U) >> 8)))
-
-#define swab32(x) \
- ((unsigned int)( \
- (((unsigned int)(x) & (unsigned int)0x000000ffUL) << 24) | \
- (((unsigned int)(x) & (unsigned int)0x0000ff00UL) << 8) | \
- (((unsigned int)(x) & (unsigned int)0x00ff0000UL) >> 8) | \
- (((unsigned int)(x) & (unsigned int)0xff000000UL) >> 24)))
-
-#define swab64(x) \
- ((uint64_t)( \
- (((uint64_t)(x) & (uint64_t)0x00000000000000ffULL) << 56) | \
- (((uint64_t)(x) & (uint64_t)0x000000000000ff00ULL) << 40) | \
- (((uint64_t)(x) & (uint64_t)0x0000000000ff0000ULL) << 24) | \
- (((uint64_t)(x) & (uint64_t)0x00000000ff000000ULL) << 8) | \
- (((uint64_t)(x) & (uint64_t)0x000000ff00000000ULL) >> 8) | \
- (((uint64_t)(x) & (uint64_t)0x0000ff0000000000ULL) >> 24) | \
- (((uint64_t)(x) & (uint64_t)0x00ff000000000000ULL) >> 40) | \
- (((uint64_t)(x) & (uint64_t)0xff00000000000000ULL) >> 56)))
-
-#endif /* _SWAB_H */
diff --git a/src/include/swab.h b/src/include/swab.h
index 956cfa5..57fe5a2 100644
--- a/src/include/swab.h
+++ b/src/include/swab.h
@@ -21,6 +21,7 @@
#include <stdint.h>
+#if defined(__ROMCC__) || ENV_ARMV4
#define swab16(x) \
((unsigned short)( \
(((unsigned short)(x) & (unsigned short)0x00ffU) << 8) | \
@@ -43,5 +44,10 @@
(((uint64_t)(x) & (uint64_t)0x0000ff0000000000ULL) >> 24) | \
(((uint64_t)(x) & (uint64_t)0x00ff000000000000ULL) >> 40) | \
(((uint64_t)(x) & (uint64_t)0xff00000000000000ULL) >> 56)))
+#else /* __ROMCC__ || ENV_ARMV4 */
+#define swab16(x) ((uint16_t)__builtin_bswap16(x))
+#define swab32(x) ((uint32_t)__builtin_bswap32(x))
+#define swab64(x) ((uint64_t)__builtin_bswap64(x))
+#endif /* !(__ROMCC__ || ENV_ARMV4) */
#endif /* _SWAB_H */
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