From d49aa55cf1b0acec040ad7fdf27fd75085ea7123 Mon Sep 17 00:00:00 2001
From: Stephen Hines <srhines@google.com>
Date: Mon, 5 Apr 2021 17:12:32 -0700
Subject: [PATCH] Remove all unused, legacy FDO build rules

There are no current users of this feature. All remaining references are
legacy scripts that aren't actually in-use today.

https://source.corp.google.com/search?q=BUILD_FDO_INSTRUMENT%20-file:build%2F
https://source.corp.google.com/search?q=LOCAL_FDO&ct=os&sq=package:%5Eandroid$

Test: build
Change-Id: I86ff6531a0868fb8e30741f0d04de1739fba4586
---
 core/binary.mk                    | 27 -------------------------
 core/clear_vars.mk                |  1 -
 core/combo/TARGET_linux-arm.mk    |  1 -
 core/combo/TARGET_linux-arm64.mk  |  1 -
 core/combo/TARGET_linux-x86.mk    |  1 -
 core/combo/TARGET_linux-x86_64.mk |  1 -
 core/combo/fdo.mk                 | 33 -------------------------------
 7 files changed, 65 deletions(-)
 delete mode 100644 core/combo/fdo.mk

diff --git a/core/binary.mk b/core/binary.mk
index 0d7206f1a..cf47374b5 100644
--- a/core/binary.mk
+++ b/core/binary.mk
@@ -471,27 +471,6 @@ ifneq ($(foreach i,$(my_c_includes),$(filter %/..,$(i))$(findstring /../,$(i))),
 my_soong_problems += dotdot_incs
 endif
 
-####################################################
-## Add FDO flags if FDO is turned on and supported
-## Please note that we will do option filtering during FDO build.
-## i.e. Os->O2, remove -fno-early-inline and -finline-limit.
-##################################################################
-my_fdo_build :=
-ifneq ($(filter true always, $(LOCAL_FDO_SUPPORT)),)
-  ifeq ($(BUILD_FDO_INSTRUMENT),true)
-    my_cflags += $($(LOCAL_2ND_ARCH_VAR_PREFIX)TARGET_FDO_INSTRUMENT_CFLAGS)
-    my_ldflags += $($(LOCAL_2ND_ARCH_VAR_PREFIX)TARGET_FDO_INSTRUMENT_LDFLAGS)
-    my_fdo_build := true
-  else ifneq ($(filter true,$(BUILD_FDO_OPTIMIZE))$(filter always,$(LOCAL_FDO_SUPPORT)),)
-    my_cflags += $($(LOCAL_2ND_ARCH_VAR_PREFIX)TARGET_FDO_OPTIMIZE_CFLAGS)
-    my_fdo_build := true
-  endif
-  # Disable ccache (or other compiler wrapper) except gomacc, which
-  # can handle -fprofile-use properly.
-  my_cc_wrapper := $(filter $(GOMA_CC) $(RBE_WRAPPER),$(my_cc_wrapper))
-  my_cxx_wrapper := $(filter $(GOMA_CC) $(RBE_WRAPPER),$(my_cxx_wrapper))
-endif
-
 ###########################################################
 ## Explicitly declare assembly-only __ASSEMBLY__ macro for
 ## assembly source
@@ -1479,12 +1458,6 @@ my_cppflags := $(call convert-to-clang-flags,$(my_cppflags))
 my_asflags := $(call convert-to-clang-flags,$(my_asflags))
 my_ldflags := $(call convert-to-clang-flags,$(my_ldflags))
 
-ifeq ($(my_fdo_build), true)
-  my_cflags := $(patsubst -Os,-O2,$(my_cflags))
-  fdo_incompatible_flags := -fno-early-inlining -finline-limit=%
-  my_cflags := $(filter-out $(fdo_incompatible_flags),$(my_cflags))
-endif
-
 # No one should ever use this flag. On GCC it's mere presence will disable all
 # warnings, even those that are specified after it (contrary to typical warning
 # flag behavior). This circumvents CFLAGS_NO_OVERRIDE from forcibly enabling the
diff --git a/core/clear_vars.mk b/core/clear_vars.mk
index 019892e5e..e2864bf27 100644
--- a/core/clear_vars.mk
+++ b/core/clear_vars.mk
@@ -100,7 +100,6 @@ LOCAL_EXPORT_STATIC_LIBRARY_HEADERS:=
 LOCAL_EXTRA_FULL_TEST_CONFIGS:=
 LOCAL_EXTRACT_APK:=
 LOCAL_EXTRACT_DPI_APK:=
-LOCAL_FDO_SUPPORT:=
 LOCAL_FILE_CONTEXTS:=
 LOCAL_FINDBUGS_FLAGS:=
 LOCAL_FORCE_STATIC_EXECUTABLE:=
diff --git a/core/combo/TARGET_linux-arm.mk b/core/combo/TARGET_linux-arm.mk
index e45c1a6ba..11c19444b 100644
--- a/core/combo/TARGET_linux-arm.mk
+++ b/core/combo/TARGET_linux-arm.mk
@@ -64,7 +64,6 @@ ifeq ($(strip $(wildcard $(TARGET_ARCH_SPECIFIC_MAKEFILE))),)
 endif
 
 include $(TARGET_ARCH_SPECIFIC_MAKEFILE)
-include $(BUILD_SYSTEM)/combo/fdo.mk
 
 define $(combo_var_prefix)transform-shared-lib-to-toc
 $(call _gen_toc_command_for_elf,$(1),$(2))
diff --git a/core/combo/TARGET_linux-arm64.mk b/core/combo/TARGET_linux-arm64.mk
index a3f59a774..5d481cb8f 100644
--- a/core/combo/TARGET_linux-arm64.mk
+++ b/core/combo/TARGET_linux-arm64.mk
@@ -39,7 +39,6 @@ $(error Unknown ARM architecture version: $(TARGET_ARCH_VARIANT))
 endif
 
 include $(TARGET_ARCH_SPECIFIC_MAKEFILE)
-include $(BUILD_SYSTEM)/combo/fdo.mk
 
 define $(combo_var_prefix)transform-shared-lib-to-toc
 $(call _gen_toc_command_for_elf,$(1),$(2))
diff --git a/core/combo/TARGET_linux-x86.mk b/core/combo/TARGET_linux-x86.mk
index 2c4614b6c..acbae519f 100644
--- a/core/combo/TARGET_linux-x86.mk
+++ b/core/combo/TARGET_linux-x86.mk
@@ -32,7 +32,6 @@ $(error Unknown $(TARGET_$(combo_2nd_arch_prefix)ARCH) architecture version: $(T
 endif
 
 include $(TARGET_ARCH_SPECIFIC_MAKEFILE)
-include $(BUILD_SYSTEM)/combo/fdo.mk
 
 define $(combo_var_prefix)transform-shared-lib-to-toc
 $(call _gen_toc_command_for_elf,$(1),$(2))
diff --git a/core/combo/TARGET_linux-x86_64.mk b/core/combo/TARGET_linux-x86_64.mk
index d2172d601..9e7e3630d 100644
--- a/core/combo/TARGET_linux-x86_64.mk
+++ b/core/combo/TARGET_linux-x86_64.mk
@@ -32,7 +32,6 @@ $(error Unknown $(TARGET_ARCH) architecture version: $(TARGET_ARCH_VARIANT))
 endif
 
 include $(TARGET_ARCH_SPECIFIC_MAKEFILE)
-include $(BUILD_SYSTEM)/combo/fdo.mk
 
 define $(combo_var_prefix)transform-shared-lib-to-toc
 $(call _gen_toc_command_for_elf,$(1),$(2))
diff --git a/core/combo/fdo.mk b/core/combo/fdo.mk
deleted file mode 100644
index 8fb8fd3a5..000000000
--- a/core/combo/fdo.mk
+++ /dev/null
@@ -1,33 +0,0 @@
-#
-# Copyright (C) 2006 The Android Open Source Project
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#      http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-#
-
-# Setup FDO related flags.
-
-$(combo_2nd_arch_prefix)TARGET_FDO_CFLAGS:=
-
-# Set BUILD_FDO_INSTRUMENT=true to turn on FDO instrumentation.
-# The profile will be generated on /sdcard/fdo_profile on the device.
-$(combo_2nd_arch_prefix)TARGET_FDO_INSTRUMENT_CFLAGS := -fprofile-generate=/sdcard/fdo_profile -DANDROID_FDO
-$(combo_2nd_arch_prefix)TARGET_FDO_INSTRUMENT_LDFLAGS := -lgcov -lgcc
-
-# Set TARGET_FDO_PROFILE_PATH to set a custom profile directory for your build.
-ifeq ($(strip $($(combo_2nd_arch_prefix)TARGET_FDO_PROFILE_PATH)),)
-  $(combo_2nd_arch_prefix)TARGET_FDO_PROFILE_PATH := vendor/google_data/fdo_profile
-endif
-
-$(combo_2nd_arch_prefix)TARGET_FDO_OPTIMIZE_CFLAGS := \
-    -fprofile-use=$($(combo_2nd_arch_prefix)TARGET_FDO_PROFILE_PATH) \
-    -DANDROID_FDO -fprofile-correction -Wcoverage-mismatch -Wno-error