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authorGravatar Abseil Team <absl-team@google.com>2022-03-28 13:12:19 -0700
committerGravatar rogeeff <rogeeff@google.com>2022-03-29 10:08:46 -0400
commit3204cc0625230e9876f0310a6dea0014210ab325 (patch)
tree7b9193fc4b720bc8e767912b8a38f82c11e19569 /absl/base/internal
parent0c6302fe427963ec5c471d3ee660120682ab15f7 (diff)
Export of internal Abseil changes
-- 291f7ef542f73e4801ab5108014bc02344ef31df by Derek Mauro <dmauro@google.com>: Internal change PiperOrigin-RevId: 437835981 Change-Id: I42fd92e74903894533ac9984d7f622e3ba20f468 -- 2e8caf1a57c50b518e05b4bca48e4fe1bb19af82 by Andy Getzendanner <durandal@google.com>: Internal change PiperOrigin-RevId: 437832673 Change-Id: I61b35089418d01a54cecf161b254b68252bebff3 -- b927482ccc399f7e337b60582988b914d9946e4e by Derek Mauro <dmauro@google.com>: Simplify endian intrinsics for modern compilers All modern compilers have either __builtin_bswapN (gcc, clang) or _byteswap_TYPE (MSVC). The other intrinsic definitions are no longer necessary. PiperOrigin-RevId: 437772295 Change-Id: Ifb3d88ba24b9097f87ceb202272b36d2f5e5117f -- b6782a2247a16d5c14706a74ec577c19963d9f97 by Derek Mauro <dmauro@google.com>: Internal change PiperOrigin-RevId: 437373174 Change-Id: I0f77e1780dee90d7a3c32a08d96c4aeb624a57b4 -- a53e0c724e37b0b01515a99bd25394b8e21ffdfc by Derek Mauro <dmauro@google.com>: Unify detection of SSE2 and SSSE3 instruction sets and include the proper headers Fix the intrinsic implementation of FastHexToBufferZeroPad16 in numbers.h which only relies on SSSE3, not SSE 4.2. https://godbolt.org/z/Pf5bn1Yv9 Closes #639 PiperOrigin-RevId: 437286940 Change-Id: Ic97948399b61b91e9c0bccd09313b795b904d714 -- f173f597cb2a75ef2a989f45a496334b85e6f40d by Abseil Team <absl-team@google.com>: Change assertion function to enable clearer error messages. PiperOrigin-RevId: 437227057 Change-Id: If420d2f63b51feef6648762f344d5be012cd9c85 GitOrigin-RevId: 291f7ef542f73e4801ab5108014bc02344ef31df
Diffstat (limited to 'absl/base/internal')
-rw-r--r--absl/base/internal/endian.h79
1 files changed, 17 insertions, 62 deletions
diff --git a/absl/base/internal/endian.h b/absl/base/internal/endian.h
index dad0e9ae..50747d75 100644
--- a/absl/base/internal/endian.h
+++ b/absl/base/internal/endian.h
@@ -16,16 +16,9 @@
#ifndef ABSL_BASE_INTERNAL_ENDIAN_H_
#define ABSL_BASE_INTERNAL_ENDIAN_H_
-// The following guarantees declaration of the byte swap functions
-#ifdef _MSC_VER
-#include <stdlib.h> // NOLINT(build/include)
-#elif defined(__FreeBSD__)
-#include <sys/endian.h>
-#elif defined(__GLIBC__)
-#include <byteswap.h> // IWYU pragma: export
-#endif
-
#include <cstdint>
+#include <cstdlib>
+
#include "absl/base/casts.h"
#include "absl/base/config.h"
#include "absl/base/internal/unaligned_access.h"
@@ -34,47 +27,11 @@
namespace absl {
ABSL_NAMESPACE_BEGIN
-// Use compiler byte-swapping intrinsics if they are available. 32-bit
-// and 64-bit versions are available in Clang and GCC as of GCC 4.3.0.
-// The 16-bit version is available in Clang and GCC only as of GCC 4.8.0.
-// For simplicity, we enable them all only for GCC 4.8.0 or later.
-#if defined(__clang__) || \
- (defined(__GNUC__) && \
- ((__GNUC__ == 4 && __GNUC_MINOR__ >= 8) || __GNUC__ >= 5))
inline uint64_t gbswap_64(uint64_t host_int) {
+#if ABSL_HAVE_BUILTIN(__builtin_bswap64) || defined(__GNUC__)
return __builtin_bswap64(host_int);
-}
-inline uint32_t gbswap_32(uint32_t host_int) {
- return __builtin_bswap32(host_int);
-}
-inline uint16_t gbswap_16(uint16_t host_int) {
- return __builtin_bswap16(host_int);
-}
-
#elif defined(_MSC_VER)
-inline uint64_t gbswap_64(uint64_t host_int) {
return _byteswap_uint64(host_int);
-}
-inline uint32_t gbswap_32(uint32_t host_int) {
- return _byteswap_ulong(host_int);
-}
-inline uint16_t gbswap_16(uint16_t host_int) {
- return _byteswap_ushort(host_int);
-}
-
-#else
-inline uint64_t gbswap_64(uint64_t host_int) {
-#if defined(__GNUC__) && defined(__x86_64__) && !defined(__APPLE__)
- // Adapted from /usr/include/byteswap.h. Not available on Mac.
- if (__builtin_constant_p(host_int)) {
- return __bswap_constant_64(host_int);
- } else {
- uint64_t result;
- __asm__("bswap %0" : "=r"(result) : "0"(host_int));
- return result;
- }
-#elif defined(__GLIBC__)
- return bswap_64(host_int);
#else
return (((host_int & uint64_t{0xFF}) << 56) |
((host_int & uint64_t{0xFF00}) << 40) |
@@ -84,12 +41,14 @@ inline uint64_t gbswap_64(uint64_t host_int) {
((host_int & uint64_t{0xFF0000000000}) >> 24) |
((host_int & uint64_t{0xFF000000000000}) >> 40) |
((host_int & uint64_t{0xFF00000000000000}) >> 56));
-#endif // bswap_64
+#endif
}
inline uint32_t gbswap_32(uint32_t host_int) {
-#if defined(__GLIBC__)
- return bswap_32(host_int);
+#if ABSL_HAVE_BUILTIN(__builtin_bswap32) || defined(__GNUC__)
+ return __builtin_bswap32(host_int);
+#elif defined(_MSC_VER)
+ return _byteswap_ulong(host_int);
#else
return (((host_int & uint32_t{0xFF}) << 24) |
((host_int & uint32_t{0xFF00}) << 8) |
@@ -99,33 +58,29 @@ inline uint32_t gbswap_32(uint32_t host_int) {
}
inline uint16_t gbswap_16(uint16_t host_int) {
-#if defined(__GLIBC__)
- return bswap_16(host_int);
+#if ABSL_HAVE_BUILTIN(__builtin_bswap16) || defined(__GNUC__)
+ return __builtin_bswap16(host_int);
+#elif defined(_MSC_VER)
+ return _byteswap_ushort(host_int);
#else
return (((host_int & uint16_t{0xFF}) << 8) |
((host_int & uint16_t{0xFF00}) >> 8));
#endif
}
-#endif // intrinsics available
-
#ifdef ABSL_IS_LITTLE_ENDIAN
-// Definitions for ntohl etc. that don't require us to include
-// netinet/in.h. We wrap gbswap_32 and gbswap_16 in functions rather
-// than just #defining them because in debug mode, gcc doesn't
-// correctly handle the (rather involved) definitions of bswap_32.
-// gcc guarantees that inline functions are as fast as macros, so
-// this isn't a performance hit.
+// Portable definitions for htonl (host-to-network) and friends on little-endian
+// architectures.
inline uint16_t ghtons(uint16_t x) { return gbswap_16(x); }
inline uint32_t ghtonl(uint32_t x) { return gbswap_32(x); }
inline uint64_t ghtonll(uint64_t x) { return gbswap_64(x); }
#elif defined ABSL_IS_BIG_ENDIAN
-// These definitions are simpler on big-endian machines
-// These are functions instead of macros to avoid self-assignment warnings
-// on calls such as "i = ghtnol(i);". This also provides type checking.
+// Portable definitions for htonl (host-to-network) etc on big-endian
+// architectures. These definitions are simpler since the host byte order is the
+// same as network byte order.
inline uint16_t ghtons(uint16_t x) { return x; }
inline uint32_t ghtonl(uint32_t x) { return x; }
inline uint64_t ghtonll(uint64_t x) { return x; }