Reset trunk to 3.24.35.4

src/a64/cpu-a64.cc

-// Copyright 2013 the V8 project authors. All rights reserved.
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
-//
-//     * Redistributions of source code must retain the above copyright
-//       notice, this list of conditions and the following disclaimer.
-//     * Redistributions in binary form must reproduce the above
-//       copyright notice, this list of conditions and the following
-//       disclaimer in the documentation and/or other materials provided
-//       with the distribution.
-//     * Neither the name of Google Inc. nor the names of its
-//       contributors may be used to endorse or promote products derived
-//       from this software without specific prior written permission.
-//
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-// CPU specific code for arm independent of OS goes here.
-
-#include "v8.h"
-
-#if V8_TARGET_ARCH_A64
-
-#include "a64/cpu-a64.h"
-#include "a64/utils-a64.h"
-
-namespace v8 {
-namespace internal {
-
-#ifdef DEBUG
-bool CpuFeatures::initialized_ = false;
-#endif
-unsigned CpuFeatures::supported_ = 0;
-unsigned CpuFeatures::found_by_runtime_probing_only_ = 0;
-unsigned CpuFeatures::cross_compile_ = 0;
-
-// Initialise to smallest possible cache size.
-unsigned CpuFeatures::dcache_line_size_ = 1;
-unsigned CpuFeatures::icache_line_size_ = 1;
-
-
-void CPU::SetUp() {
-  CpuFeatures::Probe();
-}
-
-
-bool CPU::SupportsCrankshaft() {
-  return true;
-}
-
-
-void CPU::FlushICache(void* address, size_t length) {
-  if (length == 0) {
-    return;
-  }
-
-#ifdef USE_SIMULATOR
-  // TODO(all): consider doing some cache simulation to ensure every address
-  // run has been synced.
-  USE(address);
-  USE(length);
-#else
-  // The code below assumes user space cache operations are allowed. The goal
-  // of this routine is to make sure the code generated is visible to the I
-  // side of the CPU.
-
-  uintptr_t start = reinterpret_cast<uintptr_t>(address);
-  // Sizes will be used to generate a mask big enough to cover a pointer.
-  uintptr_t dsize = static_cast<uintptr_t>(CpuFeatures::dcache_line_size());
-  uintptr_t isize = static_cast<uintptr_t>(CpuFeatures::icache_line_size());
-  // Cache line sizes are always a power of 2.
-  ASSERT(CountSetBits(dsize, 64) == 1);
-  ASSERT(CountSetBits(isize, 64) == 1);
-  uintptr_t dstart = start & ~(dsize - 1);
-  uintptr_t istart = start & ~(isize - 1);
-  uintptr_t end = start + length;
-
-  __asm__ __volatile__ (  // NOLINT
-    // Clean every line of the D cache containing the target data.
-    "0:                                \n\t"
-    // dc      : Data Cache maintenance
-    //    c    : Clean
-    //     va  : by (Virtual) Address
-    //       u : to the point of Unification
-    // The point of unification for a processor is the point by which the
-    // instruction and data caches are guaranteed to see the same copy of a
-    // memory location. See ARM DDI 0406B page B2-12 for more information.
-    "dc   cvau, %[dline]                \n\t"
-    "add  %[dline], %[dline], %[dsize]  \n\t"
-    "cmp  %[dline], %[end]              \n\t"
-    "b.lt 0b                            \n\t"
-    // Barrier to make sure the effect of the code above is visible to the rest
-    // of the world.
-    // dsb    : Data Synchronisation Barrier
-    //    ish : Inner SHareable domain
-    // The point of unification for an Inner Shareable shareability domain is
-    // the point by which the instruction and data caches of all the processors
-    // in that Inner Shareable shareability domain are guaranteed to see the
-    // same copy of a memory location.  See ARM DDI 0406B page B2-12 for more
-    // information.
-    "dsb  ish                           \n\t"
-    // Invalidate every line of the I cache containing the target data.
-    "1:                                 \n\t"
-    // ic      : instruction cache maintenance
-    //    i    : invalidate
-    //     va  : by address
-    //       u : to the point of unification
-    "ic   ivau, %[iline]                \n\t"
-    "add  %[iline], %[iline], %[isize]  \n\t"
-    "cmp  %[iline], %[end]              \n\t"
-    "b.lt 1b                            \n\t"
-    // Barrier to make sure the effect of the code above is visible to the rest
-    // of the world.
-    "dsb  ish                           \n\t"
-    // Barrier to ensure any prefetching which happened before this code is
-    // discarded.
-    // isb : Instruction Synchronisation Barrier
-    "isb                                \n\t"
-    : [dline] "+r" (dstart),
-      [iline] "+r" (istart)
-    : [dsize] "r"  (dsize),
-      [isize] "r"  (isize),
-      [end]   "r"  (end)
-    // This code does not write to memory but without the dependency gcc might
-    // move this code before the code is generated.
-    : "cc", "memory"
-  );  // NOLINT
-#endif
-}
-
-
-void CpuFeatures::Probe() {
-  // Compute I and D cache line size. The cache type register holds
-  // information about the caches.
-  uint32_t cache_type_register = GetCacheType();
-
-  static const int kDCacheLineSizeShift = 16;
-  static const int kICacheLineSizeShift = 0;
-  static const uint32_t kDCacheLineSizeMask = 0xf << kDCacheLineSizeShift;
-  static const uint32_t kICacheLineSizeMask = 0xf << kICacheLineSizeShift;
-
-  // The cache type register holds the size of the I and D caches as a power of
-  // two.
-  uint32_t dcache_line_size_power_of_two =
-      (cache_type_register & kDCacheLineSizeMask) >> kDCacheLineSizeShift;
-  uint32_t icache_line_size_power_of_two =
-      (cache_type_register & kICacheLineSizeMask) >> kICacheLineSizeShift;
-
-  dcache_line_size_ = 1 << dcache_line_size_power_of_two;
-  icache_line_size_ = 1 << icache_line_size_power_of_two;
-
-  // AArch64 has no configuration options, no further probing is required.
-  supported_ = 0;
-
-#ifdef DEBUG
-  initialized_ = true;
-#endif
-}
-
-
-unsigned CpuFeatures::dcache_line_size() {
-  ASSERT(initialized_);
-  return dcache_line_size_;
-}
-
-
-unsigned CpuFeatures::icache_line_size() {
-  ASSERT(initialized_);
-  return icache_line_size_;
-}
-
-
-uint32_t CpuFeatures::GetCacheType() {
-#ifdef USE_SIMULATOR
-  // This will lead to a cache with 1 byte long lines, which is fine since the
-  // simulator will not need this information.
-  return 0;
-#else
-  uint32_t cache_type_register;
-  // Copy the content of the cache type register to a core register.
-  __asm__ __volatile__ ("mrs %[ctr], ctr_el0"  // NOLINT
-                        : [ctr] "=r" (cache_type_register));
-  return cache_type_register;
-#endif
-}
-
-} }  // namespace v8::internal
-
-#endif  // V8_TARGET_ARCH_A64