# Copyright 2014 The Chromium Authors. All rights reserved. # Use of this source code is governed by a BSD-style license that can be # found in the LICENSE file. import("//build/config/chromeos/ui_mode.gni") import("//build/config/v8_target_cpu.gni") # 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" || v8_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 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 } # For lacros build, we use ARM v8 by default. if (is_chromeos_lacros && arm_arch == "") { arm_version = 8 arm_arch = "armv8-a+crc" } if (current_os == "android" || target_os == "android") { arm_float_abi = "softfp" } else { declare_args() { # 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 = "" } } assert(arm_float_abi == "" || arm_float_abi == "hard" || arm_float_abi == "soft" || arm_float_abi == "softfp") if (arm_use_neon == "") { if (current_os == "linux" && target_cpu != v8_target_cpu) { # Don't use neon on V8 simulator builds as a default. arm_use_neon = false } else { arm_use_neon = true } } if (arm_version == 6) { if (arm_arch == "") { # v8 can still with version 6 but only with the armv6k extension. arm_arch = "armv6k" } 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_float_abi == "") { if (current_os == "linux" && target_cpu != v8_target_cpu) { # Default to the same as Android for V8 simulator builds. 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 == "") { arm_float_abi = "hard" } if (arm_fpu == "") { if (arm_use_neon) { arm_fpu = "neon" } else { arm_fpu = "vfpv3-d16" } } } } else if (current_cpu == "arm64" || v8_current_cpu == "arm64") { # arm64 supports only "hard". arm_float_abi = "hard" arm_use_neon = true declare_args() { # Enables the new Armv8 branch protection features. Valid strings are: # - "pac": Enables Pointer Authentication Code (PAC, featured in Armv8.3) # - "standard": Enables both PAC and Branch Target Identification (Armv8.5). # - "none": No branch protection. arm_control_flow_integrity = "standard" # TODO(cavalcantii): enable the feature for the following OSes next. if (is_mac || is_chromeos || is_fuchsia || is_win || target_cpu != "arm64") { # target_cpu != "arm64" covers some cases (e.g. the ChromeOS x64 MSAN # build) where the target platform is x64, but V8 is configured to use # the arm64 simulator. Pointer authentication doesn't work properly # in this mode (yet). arm_control_flow_integrity = "none" } } assert(arm_control_flow_integrity == "none" || arm_control_flow_integrity == "standard" || arm_control_flow_integrity == "pac", "Invalid branch protection option") }