chromium/third_party/crashpad/crashpad/snapshot/linux/cpu_context_linux.cc

// Copyright 2017 The Crashpad 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
//
//     http://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.

#include "snapshot/linux/cpu_context_linux.h"

#include <stddef.h>
#include <string.h>

#include <limits>

#include "base/logging.h"

namespace crashpad {
namespace internal {

#if defined(ARCH_CPU_X86_FAMILY)

#define SET_GPRS32() …

void InitializeCPUContextX86(const ThreadContext::t32_t& thread_context,
                             const FloatContext::f32_t& float_context,
                             CPUContextX86* context) { … }

void InitializeCPUContextX86(const SignalThreadContext32& thread_context,
                             const SignalFloatContext32& float_context,
                             CPUContextX86* context) { … }

void InitializeCPUContextX86_NoFloatingPoint(
    const SignalThreadContext32& thread_context,
    CPUContextX86* context) { … }

#define SET_GPRS64() …

void InitializeCPUContextX86_64(const ThreadContext::t64_t& thread_context,
                                const FloatContext::f64_t& float_context,
                                CPUContextX86_64* context) { … }

void InitializeCPUContextX86_64(const SignalThreadContext64& thread_context,
                                const SignalFloatContext64& float_context,
                                CPUContextX86_64* context) { … }

void InitializeCPUContextX86_64_NoFloatingPoint(
    const SignalThreadContext64& thread_context,
    CPUContextX86_64* context) { … }

#elif defined(ARCH_CPU_ARM_FAMILY)

void InitializeCPUContextARM(const ThreadContext::t32_t& thread_context,
                             const FloatContext::f32_t& float_context,
                             CPUContextARM* context) {
  static_assert(sizeof(context->regs) == sizeof(thread_context.regs),
                "registers size mismatch");
  memcpy(&context->regs, &thread_context.regs, sizeof(context->regs));
  context->fp = thread_context.fp;
  context->ip = thread_context.ip;
  context->sp = thread_context.sp;
  context->lr = thread_context.lr;
  context->pc = thread_context.pc;
  context->cpsr = thread_context.cpsr;

  static_assert(sizeof(context->vfp_regs) == sizeof(float_context.vfp),
                "vfp size mismatch");
  context->have_vfp_regs = float_context.have_vfp;
  if (float_context.have_vfp) {
    memcpy(&context->vfp_regs, &float_context.vfp, sizeof(context->vfp_regs));
  }

  static_assert(sizeof(context->fpa_regs) == sizeof(float_context.fpregs),
                "fpregs size mismatch");
  context->have_fpa_regs = float_context.have_fpregs;
  if (float_context.have_fpregs) {
    memcpy(
        &context->fpa_regs, &float_context.fpregs, sizeof(context->fpa_regs));
  }
}

void InitializeCPUContextARM_NoFloatingPoint(
    const SignalThreadContext32& thread_context,
    CPUContextARM* context) {
  static_assert(sizeof(context->regs) == sizeof(thread_context.regs),
                "registers size mismatch");
  memcpy(&context->regs, &thread_context.regs, sizeof(context->regs));
  context->fp = thread_context.fp;
  context->ip = thread_context.ip;
  context->sp = thread_context.sp;
  context->lr = thread_context.lr;
  context->pc = thread_context.pc;
  context->cpsr = thread_context.cpsr;

  memset(&context->fpa_regs, 0, sizeof(context->fpa_regs));
  memset(&context->vfp_regs, 0, sizeof(context->vfp_regs));
  context->have_fpa_regs = false;
  context->have_vfp_regs = false;
}

void InitializeCPUContextARM64(const ThreadContext::t64_t& thread_context,
                               const FloatContext::f64_t& float_context,
                               CPUContextARM64* context) {
  InitializeCPUContextARM64_NoFloatingPoint(thread_context, context);

  static_assert(sizeof(context->fpsimd) == sizeof(float_context.vregs),
                "fpsimd context size mismatch");
  memcpy(context->fpsimd, float_context.vregs, sizeof(context->fpsimd));
  context->fpsr = float_context.fpsr;
  context->fpcr = float_context.fpcr;
}

void InitializeCPUContextARM64_NoFloatingPoint(
    const ThreadContext::t64_t& thread_context,
    CPUContextARM64* context) {
  static_assert(sizeof(context->regs) == sizeof(thread_context.regs),
                "gpr context size mismtach");
  memcpy(context->regs, thread_context.regs, sizeof(context->regs));
  context->sp = thread_context.sp;
  context->pc = thread_context.pc;
  // Linux seems to only be putting the SPSR register in its "pstate" field.
  // https://elixir.bootlin.com/linux/latest/source/arch/arm64/include/uapi/asm/ptrace.h
  if (thread_context.pstate >
      std::numeric_limits<decltype(context->spsr)>::max()) {
    LOG(WARNING) << "pstate truncation: we only expect the SPSR bits to be set "
                    "in the pstate";
  }
  context->spsr = static_cast<decltype(context->spsr)>(thread_context.pstate);

  memset(&context->fpsimd, 0, sizeof(context->fpsimd));
  context->fpsr = 0;
  context->fpcr = 0;
}

void InitializeCPUContextARM64_OnlyFPSIMD(
    const SignalFPSIMDContext& float_context,
    CPUContextARM64* context) {
  static_assert(sizeof(context->fpsimd) == sizeof(float_context.vregs),
                "fpsimd context size mismatch");
  memcpy(context->fpsimd, float_context.vregs, sizeof(context->fpsimd));
  context->fpsr = float_context.fpsr;
  context->fpcr = float_context.fpcr;
}

#elif defined(ARCH_CPU_RISCV64)

void InitializeCPUContextRISCV64(const ThreadContext::t64_t& thread_context,
                                 const FloatContext::f64_t& float_context,
                                 CPUContextRISCV64* context) {
  context->pc = thread_context.pc;

  static_assert(sizeof(context->regs) == sizeof(thread_context.regs));
  memcpy(context->regs, thread_context.regs, sizeof(context->regs));

  static_assert(sizeof(context->fpregs) == sizeof(float_context.fpregs));
  memcpy(context->fpregs, float_context.fpregs, sizeof(context->fpregs));
  context->fcsr = float_context.fcsr;
}

#endif  // ARCH_CPU_X86_FAMILY

}  // namespace internal
}  // namespace crashpad