chore(3p/abseil_cpp): unvendor abseil_cpp r/3786

we weren't actually using these sources anymore, okay?

Change-Id: If701571d9716de308d3512e1eb22c35db0877a66
Reviewed-on: https://cl.tvl.fyi/c/depot/+/5248
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
Autosubmit: tazjin <tazjin@tvl.su>

1 files changed, 0 insertions, 221 deletions

diff --git a/third_party/abseil_cpp/absl/random/internal/randen_detect.cc b/third_party/abseil_cpp/absl/random/internal/randen_detect.cc
deleted file mode 100644
index bbe7b965329c..000000000000
--- a/third_party/abseil_cpp/absl/random/internal/randen_detect.cc
+++ /dev/null
@@ -1,221 +0,0 @@
-// Copyright 2017 The Abseil Authors.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//      https://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-// HERMETIC NOTE: The randen_hwaes target must not introduce duplicate
-// symbols from arbitrary system and other headers, since it may be built
-// with different flags from other targets, using different levels of
-// optimization, potentially introducing ODR violations.
-
-#include "absl/random/internal/randen_detect.h"
-
-#include <cstdint>
-#include <cstring>
-
-#include "absl/random/internal/platform.h"
-
-#if defined(ABSL_ARCH_X86_64)
-#define ABSL_INTERNAL_USE_X86_CPUID
-#elif defined(ABSL_ARCH_PPC) || defined(ABSL_ARCH_ARM) || \
-    defined(ABSL_ARCH_AARCH64)
-#if defined(__ANDROID__)
-#define ABSL_INTERNAL_USE_ANDROID_GETAUXVAL
-#define ABSL_INTERNAL_USE_GETAUXVAL
-#elif defined(__linux__)
-#define ABSL_INTERNAL_USE_LINUX_GETAUXVAL
-#define ABSL_INTERNAL_USE_GETAUXVAL
-#endif
-#endif
-
-#if defined(ABSL_INTERNAL_USE_X86_CPUID)
-#if defined(_WIN32) || defined(_WIN64)
-#include <intrin.h>  // NOLINT(build/include_order)
-#pragma intrinsic(__cpuid)
-#else
-// MSVC-equivalent __cpuid intrinsic function.
-static void __cpuid(int cpu_info[4], int info_type) {
-  __asm__ volatile("cpuid \n\t"
-                   : "=a"(cpu_info[0]), "=b"(cpu_info[1]), "=c"(cpu_info[2]),
-                     "=d"(cpu_info[3])
-                   : "a"(info_type), "c"(0));
-}
-#endif
-#endif  // ABSL_INTERNAL_USE_X86_CPUID
-
-// On linux, just use the c-library getauxval call.
-#if defined(ABSL_INTERNAL_USE_LINUX_GETAUXVAL)
-
-extern "C" unsigned long getauxval(unsigned long type);  // NOLINT(runtime/int)
-
-static uint32_t GetAuxval(uint32_t hwcap_type) {
-  return static_cast<uint32_t>(getauxval(hwcap_type));
-}
-
-#endif
-
-// On android, probe the system's C library for getauxval().
-// This is the same technique used by the android NDK cpu features library
-// as well as the google open-source cpu_features library.
-//
-// TODO(absl-team): Consider implementing a fallback of directly reading
-// /proc/self/auxval.
-#if defined(ABSL_INTERNAL_USE_ANDROID_GETAUXVAL)
-#include <dlfcn.h>
-
-static uint32_t GetAuxval(uint32_t hwcap_type) {
-  // NOLINTNEXTLINE(runtime/int)
-  typedef unsigned long (*getauxval_func_t)(unsigned long);
-
-  dlerror();  // Cleaning error state before calling dlopen.
-  void* libc_handle = dlopen("libc.so", RTLD_NOW);
-  if (!libc_handle) {
-    return 0;
-  }
-  uint32_t result = 0;
-  void* sym = dlsym(libc_handle, "getauxval");
-  if (sym) {
-    getauxval_func_t func;
-    memcpy(&func, &sym, sizeof(func));
-    result = static_cast<uint32_t>((*func)(hwcap_type));
-  }
-  dlclose(libc_handle);
-  return result;
-}
-
-#endif
-
-namespace absl {
-ABSL_NAMESPACE_BEGIN
-namespace random_internal {
-
-// The default return at the end of the function might be unreachable depending
-// on the configuration. Ignore that warning.
-#if defined(__clang__)
-#pragma clang diagnostic push
-#pragma clang diagnostic ignored "-Wunreachable-code-return"
-#endif
-
-// CPUSupportsRandenHwAes returns whether the CPU is a microarchitecture
-// which supports the crpyto/aes instructions or extensions necessary to use the
-// accelerated RandenHwAes implementation.
-//
-// 1. For x86 it is sufficient to use the CPUID instruction to detect whether
-//    the cpu supports AES instructions. Done.
-//
-// Fon non-x86 it is much more complicated.
-//
-// 2. When ABSL_INTERNAL_USE_GETAUXVAL is defined, use getauxval() (either
-//    the direct c-library version, or the android probing version which loads
-//    libc), and read the hardware capability bits.
-//    This is based on the technique used by boringssl uses to detect
-//    cpu capabilities, and should allow us to enable crypto in the android
-//    builds where it is supported.
-//
-// 3. Use the default for the compiler architecture.
-//
-
-bool CPUSupportsRandenHwAes() {
-#if defined(ABSL_INTERNAL_USE_X86_CPUID)
-  // 1. For x86: Use CPUID to detect the required AES instruction set.
-  int regs[4];
-  __cpuid(reinterpret_cast<int*>(regs), 1);
-  return regs[2] & (1 << 25);  // AES
-
-#elif defined(ABSL_INTERNAL_USE_GETAUXVAL)
-  // 2. Use getauxval() to read the hardware bits and determine
-  // cpu capabilities.
-
-#define AT_HWCAP 16
-#define AT_HWCAP2 26
-#if defined(ABSL_ARCH_PPC)
-  // For Power / PPC: Expect that the cpu supports VCRYPTO
-  // See https://members.openpowerfoundation.org/document/dl/576
-  // VCRYPTO should be present in POWER8 >= 2.07.
-  // Uses Linux kernel constants from arch/powerpc/include/uapi/asm/cputable.h
-  static const uint32_t kVCRYPTO = 0x02000000;
-  const uint32_t hwcap = GetAuxval(AT_HWCAP2);
-  return (hwcap & kVCRYPTO) != 0;
-
-#elif defined(ABSL_ARCH_ARM)
-  // For ARM: Require crypto+neon
-  // http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0500f/CIHBIBBA.html
-  // Uses Linux kernel constants from arch/arm64/include/asm/hwcap.h
-  static const uint32_t kNEON = 1 << 12;
-  uint32_t hwcap = GetAuxval(AT_HWCAP);
-  if ((hwcap & kNEON) == 0) {
-    return false;
-  }
-
-  // And use it again to detect AES.
-  static const uint32_t kAES = 1 << 0;
-  const uint32_t hwcap2 = GetAuxval(AT_HWCAP2);
-  return (hwcap2 & kAES) != 0;
-
-#elif defined(ABSL_ARCH_AARCH64)
-  // For AARCH64: Require crypto+neon
-  // http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0500f/CIHBIBBA.html
-  static const uint32_t kNEON = 1 << 1;
-  static const uint32_t kAES = 1 << 3;
-  const uint32_t hwcap = GetAuxval(AT_HWCAP);
-  return ((hwcap & kNEON) != 0) && ((hwcap & kAES) != 0);
-#endif
-
-#else  // ABSL_INTERNAL_USE_GETAUXVAL
-  // 3. By default, assume that the compiler default.
-  return ABSL_HAVE_ACCELERATED_AES ? true : false;
-
-#endif
-  // NOTE: There are some other techniques that may be worth trying:
-  //
-  // * Use an environment variable: ABSL_RANDOM_USE_HWAES
-  //
-  // * Rely on compiler-generated target-based dispatch.
-  // Using x86/gcc it might look something like this:
-  //
-  // int __attribute__((target("aes"))) HasAes() { return 1; }
-  // int __attribute__((target("default"))) HasAes() { return 0; }
-  //
-  // This does not work on all architecture/compiler combinations.
-  //
-  // * On Linux consider reading /proc/cpuinfo and/or /proc/self/auxv.
-  // These files have lines which are easy to parse; for ARM/AARCH64 it is quite
-  // easy to find the Features: line and extract aes / neon. Likewise for
-  // PPC.
-  //
-  // * Fork a process and test for SIGILL:
-  //
-  // * Many architectures have instructions to read the ISA. Unfortunately
-  //   most of those require that the code is running in ring 0 /
-  //   protected-mode.
-  //
-  //   There are several examples. e.g. Valgrind detects PPC ISA 2.07:
-  //   https://github.com/lu-zero/valgrind/blob/master/none/tests/ppc64/test_isa_2_07_part1.c
-  //
-  //   MRS <Xt>, ID_AA64ISAR0_EL1 ; Read ID_AA64ISAR0_EL1 into Xt
-  //
-  //   uint64_t val;
-  //   __asm __volatile("mrs %0, id_aa64isar0_el1" :"=&r" (val));
-  //
-  // * Use a CPUID-style heuristic database.
-  //
-  // * On Apple (__APPLE__), AES is available on Arm v8.
-  //   https://stackoverflow.com/questions/45637888/how-to-determine-armv8-features-at-runtime-on-ios
-}
-
-#if defined(__clang__)
-#pragma clang diagnostic pop
-#endif
-
-}  // namespace random_internal
-ABSL_NAMESPACE_END
-}  // namespace absl