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authorGravatar Abseil Team <absl-team@google.com>2020-03-31 12:32:35 -0700
committerGravatar Andy Getz <durandal@google.com>2020-03-31 16:34:04 -0400
commitfba8a316c30690097de5d6127ad307d84a1b74ca (patch)
tree952cde69de3f0bca33453bf166514711e3abd5e0 /absl/base/internal/bits.h
parent79e0dc11514df035a8d07a356f9ee1800fb2160c (diff)
Export of internal Abseil changes
-- 2dd5008c7b4176859e320c7c337078adb173b662 by Tom Manshreck <shreck@google.com>: Internal change PiperOrigin-RevId: 304022549 -- 6442abd78697b03cfe698b0d0dac7f1eb4b5cb38 by Andy Getzendanner <durandal@google.com>: Internal change PiperOrigin-RevId: 303890410 -- eb8b37b468b0f23da09d3de714272928ef61f942 by Gennadiy Rozental <rogeeff@google.com>: Roll changes forward with ChunkIterator templatized. This should facilitate usage of "small" chunk iterator for a regular usage and proper "big" iterator internally in Cord implementation. This way Cord users are not exposed to stack size overhead if they have a lot of chunk iterators or recursive implementation which relies on chunk iterators. PiperOrigin-RevId: 303877118 -- 9623c569e7c55b45254e95f2d14c5badf9c901aa by Gennadiy Rozental <rogeeff@google.com>: Switch Flags implementation of fast type id to use absl/base/internal/fast_type_id.h PiperOrigin-RevId: 303861019 -- e2931e8d53c86d0816da6bbc8ba58cf5a3a443bb by Matthew Brown <matthewbr@google.com>: Internal Change PiperOrigin-RevId: 303832407 -- b549ed6e441e920b8ad6f02a80b9fd543820ef86 by Tom Manshreck <shreck@google.com>: Update Cord header file comments to Abseil standards PiperOrigin-RevId: 303823232 -- fc633d4f31a2d058f2b6a7029fc7c9820cd71c92 by Evan Brown <ezb@google.com>: Remove top-level const from K/V in map_slot_type::mutable_value and map_slot_type::key. This allows us to move between `map_slot_type::mutable_value`s internally even when the key_type and/or mapped_type specified by the user are const. PiperOrigin-RevId: 303811694 -- 909b3ce7cb3583ee9c374d36ff5f82bba02a1b64 by Derek Mauro <dmauro@google.com>: Add hardening assertions to the preconditions of absl::Cord PiperOrigin-RevId: 303419537 -- 9d32f79eabd54e6cb17bcc28b53e9bcfeb3cf6f4 by Greg Falcon <gfalcon@google.com>: Don't use MSVC-specific bit manipulations when using Clang on Windows. This fixes a compiler warning. Note that we do not have continuous testing for this configuration; this CL is best-effort support. PiperOrigin-RevId: 303322582 -- f6e0a35a2b9081d2a9eef73789b7bc1b5e46e5ad by Gennadiy Rozental <rogeeff@google.com>: Introduce standlone FastTypeId utility to represent compile time unique type id. PiperOrigin-RevId: 303180545 -- 99120e9fbdb5b2d327139ab8f617533d7bc3345b by Abseil Team <absl-team@google.com>: Changed absl's import of std::string_view to using string_view = std::string_view. This should help tools (e.g. include-what-you-use) discover where absl::string_view is defined. PiperOrigin-RevId: 303169095 GitOrigin-RevId: 2dd5008c7b4176859e320c7c337078adb173b662 Change-Id: I1e18ae08e23686ac963e7ea5e5bd499e18d51048
Diffstat (limited to 'absl/base/internal/bits.h')
-rw-r--r--absl/base/internal/bits.h24
1 files changed, 12 insertions, 12 deletions
diff --git a/absl/base/internal/bits.h b/absl/base/internal/bits.h
index 8b03453c..14c51d8b 100644
--- a/absl/base/internal/bits.h
+++ b/absl/base/internal/bits.h
@@ -24,7 +24,7 @@
// Clang on Windows has __builtin_clzll; otherwise we need to use the
// windows intrinsic functions.
-#if defined(_MSC_VER)
+#if defined(_MSC_VER) && !defined(__clang__)
#include <intrin.h>
#if defined(_M_X64)
#pragma intrinsic(_BitScanReverse64)
@@ -36,7 +36,7 @@
#include "absl/base/attributes.h"
-#if defined(_MSC_VER)
+#if defined(_MSC_VER) && !defined(__clang__)
// We can achieve something similar to attribute((always_inline)) with MSVC by
// using the __forceinline keyword, however this is not perfect. MSVC is
// much less aggressive about inlining, and even with the __forceinline keyword.
@@ -73,14 +73,14 @@ ABSL_BASE_INTERNAL_FORCEINLINE int CountLeadingZeros64Slow(uint64_t n) {
}
ABSL_BASE_INTERNAL_FORCEINLINE int CountLeadingZeros64(uint64_t n) {
-#if defined(_MSC_VER) && defined(_M_X64)
+#if defined(_MSC_VER) && !defined(__clang__) && defined(_M_X64)
// MSVC does not have __buitin_clzll. Use _BitScanReverse64.
unsigned long result = 0; // NOLINT(runtime/int)
if (_BitScanReverse64(&result, n)) {
return 63 - result;
}
return 64;
-#elif defined(_MSC_VER)
+#elif defined(_MSC_VER) && !defined(__clang__)
// MSVC does not have __buitin_clzll. Compose two calls to _BitScanReverse
unsigned long result = 0; // NOLINT(runtime/int)
if ((n >> 32) && _BitScanReverse(&result, n >> 32)) {
@@ -90,7 +90,7 @@ ABSL_BASE_INTERNAL_FORCEINLINE int CountLeadingZeros64(uint64_t n) {
return 63 - result;
}
return 64;
-#elif defined(__GNUC__)
+#elif defined(__GNUC__) || defined(__clang__)
// Use __builtin_clzll, which uses the following instructions:
// x86: bsr
// ARM64: clz
@@ -126,13 +126,13 @@ ABSL_BASE_INTERNAL_FORCEINLINE int CountLeadingZeros32Slow(uint64_t n) {
}
ABSL_BASE_INTERNAL_FORCEINLINE int CountLeadingZeros32(uint32_t n) {
-#if defined(_MSC_VER)
+#if defined(_MSC_VER) && !defined(__clang__)
unsigned long result = 0; // NOLINT(runtime/int)
if (_BitScanReverse(&result, n)) {
return 31 - result;
}
return 32;
-#elif defined(__GNUC__)
+#elif defined(__GNUC__) || defined(__clang__)
// Use __builtin_clz, which uses the following instructions:
// x86: bsr
// ARM64: clz
@@ -163,11 +163,11 @@ ABSL_BASE_INTERNAL_FORCEINLINE int CountTrailingZerosNonZero64Slow(uint64_t n) {
}
ABSL_BASE_INTERNAL_FORCEINLINE int CountTrailingZerosNonZero64(uint64_t n) {
-#if defined(_MSC_VER) && defined(_M_X64)
+#if defined(_MSC_VER) && !defined(__clang__) && defined(_M_X64)
unsigned long result = 0; // NOLINT(runtime/int)
_BitScanForward64(&result, n);
return result;
-#elif defined(_MSC_VER)
+#elif defined(_MSC_VER) && !defined(__clang__)
unsigned long result = 0; // NOLINT(runtime/int)
if (static_cast<uint32_t>(n) == 0) {
_BitScanForward(&result, n >> 32);
@@ -175,7 +175,7 @@ ABSL_BASE_INTERNAL_FORCEINLINE int CountTrailingZerosNonZero64(uint64_t n) {
}
_BitScanForward(&result, n);
return result;
-#elif defined(__GNUC__)
+#elif defined(__GNUC__) || defined(__clang__)
static_assert(sizeof(unsigned long long) == sizeof(n), // NOLINT(runtime/int)
"__builtin_ctzll does not take 64-bit arg");
return __builtin_ctzll(n);
@@ -196,11 +196,11 @@ ABSL_BASE_INTERNAL_FORCEINLINE int CountTrailingZerosNonZero32Slow(uint32_t n) {
}
ABSL_BASE_INTERNAL_FORCEINLINE int CountTrailingZerosNonZero32(uint32_t n) {
-#if defined(_MSC_VER)
+#if defined(_MSC_VER) && !defined(__clang__)
unsigned long result = 0; // NOLINT(runtime/int)
_BitScanForward(&result, n);
return result;
-#elif defined(__GNUC__)
+#elif defined(__GNUC__) || defined(__clang__)
static_assert(sizeof(int) == sizeof(n),
"__builtin_ctz does not take 32-bit arg");
return __builtin_ctz(n);