xref: /arkcompiler/toolchain/build/config/arm.gni (revision e509ee18)

# Copyright (c) 2023 Huawei Device Co., Ltd.
# 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.

# These are primarily relevant in current_cpu == "arm" contexts, where
# ARM code is being compiled.  But they can also be relevant in the
# other contexts when the code will change its behavior based on the
# cpu it wants to generate code for.
if (current_cpu == "arm") {
  declare_args() {
    # Version of the ARM processor when compiling on ARM. Ignored on non-ARM
    # platforms.
    arm_version = 7

    # The ARM architecture. This will be a string like "armv6" or "armv7-a".
    # An empty string means to use the default for the arm_version.
    arm_arch = ""

    # The ARM floating point hardware. This will be a string like "neon" or
    # "vfpv3". An empty string means to use the default for the arm_version.
    arm_fpu = ""

    # The ARM floating point mode. This is either the string "hard", "soft", or
    # "softfp". An empty string means to use the default one for the
    # arm_version.
    arm_float_abi = ""

    # The ARM variant-specific tuning mode. This will be a string like "armv6"
    # or "cortex-a15". An empty string means to use the default for the
    # arm_version.
    arm_tune = ""

    # Whether to use the neon FPU instruction set or not.
    arm_use_neon = ""

    # Whether to enable optional NEON code paths.
    arm_optionally_use_neon = false

    # Thumb is a reduced instruction set available on some ARM processors that
    # has increased code density.
    arm_use_thumb = true
  }

  assert(arm_float_abi == "" || arm_float_abi == "hard" ||
         arm_float_abi == "soft" || arm_float_abi == "softfp")

  if (arm_use_neon == "") {
    if (current_os == "linux") {
      # Don't use neon as a default.
      arm_use_neon = false
    } else {
      arm_use_neon = true
    }
  }

  if (arm_version == 6) {
    if (arm_arch == "") {
      arm_arch = "armv6"
    }
    if (arm_tune != "") {
      arm_tune = ""
    }
    if (arm_float_abi == "") {
      arm_float_abi = "softfp"
    }
    if (arm_fpu == "") {
      arm_fpu = "vfp"
    }
    arm_use_thumb = false
    arm_use_neon = false
  } else if (arm_version == 7) {
    if (arm_arch == "") {
      arm_arch = "armv7-a"
    }
    if (arm_tune == "") {
      arm_tune = "generic-armv7-a"
    }

    if (arm_float_abi == "") {
      if (current_os == "ohos" || target_os == "ohos") {
        arm_float_abi = "softfp"
      } else if (current_os == "linux") {
        arm_float_abi = "softfp"
      } else {
        arm_float_abi = "hard"
      }
    }

    if (arm_fpu == "") {
      if (arm_use_neon) {
        arm_fpu = "neon"
      } else {
        arm_fpu = "vfpv3-d16"
      }
    }
  } else if (arm_version == 8) {
    if (arm_arch == "") {
      arm_arch = "armv8-a"
    }
    if (arm_tune == "") {
      arm_tune = "generic-armv8-a"
    }

    if (arm_float_abi == "") {
      if (current_os == "ohos" || target_os == "ohos") {
        arm_float_abi = "softfp"
      } else {
        arm_float_abi = "hard"
      }
    }

    if (arm_fpu == "") {
      if (arm_use_neon) {
        arm_fpu = "neon"
      } else {
        arm_fpu = "vfpv3-d16"
      }
    }
  }
} else if (current_cpu == "arm64") {
  if (!defined(board_arch)) {
    arm_arch = "armv8-a"
  } else {
    arm_arch = "$board_arch"
  }
  if (!defined(board_cpu)) {
    arm_cpu = "cortex-a55"
  } else {
    arm_cpu = "$board_cpu"
  }
  if (!defined(board_fpu)) {
    arm_fpu = "neon-fp-armv8"
  } else {
    arm_fpu = "$board_fpu"
  }

  # arm64 supports only "hard".
  arm_float_abi = "hard"
  arm_use_neon = true
}