Resolve TODO now that the feature configuration supports conditional expansion

of flag sets.

--
MOS_MIGRATED_REVID=100400672

2 files changed, 67 insertions, 78 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/rules/cpp/CppConfiguration.java b/src/main/java/com/google/devtools/build/lib/rules/cpp/CppConfiguration.java
index 8d66f01753..c999e7fad7 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/cpp/CppConfiguration.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/cpp/CppConfiguration.java
@@ -719,69 +719,81 @@ public class CppConfiguration extends BuildConfiguration.Fragment {
             toolchainBuilder);
       }
       if (!features.contains("fdo_instrument")) {
-        TextFormat.merge(""
-            + "feature {"
-            + "  name: 'fdo_instrument'"
-            + "  flag_set {"
-            + "    action: 'c-compile'"
-            + "    action: 'c++-compile'"
-            + "    action: 'c++-link'"
-            + "    flag_group {"
-            + "      flag: '-Xgcc-only=-fprofile-generate=%{fdo_instrument_path}'"
-            + "      flag: '-Xclang-only=-fprofile-instr-generate=%{fdo_instrument_path}'"
-            + "    }"
-            + "    flag_group {"
-            + "      flag: '-fno-data-sections'"
-            + "    }"
-            + "  }"
-            + "}",
+        TextFormat.merge(
+            ""
+                + "feature {"
+                + "  name: 'fdo_instrument'"
+                + "  provides: 'profile'"
+                + "  flag_set {"
+                + "    action: 'c-compile'"
+                + "    action: 'c++-compile'"
+                + "    action: 'c++-link'"
+                + "    flag_group {"
+                + "      flag: '-Xgcc-only=-fprofile-generate=%{fdo_instrument_path}'"
+                + "      flag: '-Xclang-only=-fprofile-instr-generate=%{fdo_instrument_path}'"
+                + "    }"
+                + "    flag_group {"
+                + "      flag: '-fno-data-sections'"
+                + "    }"
+                + "  }"
+                + "}",
             toolchainBuilder);
       }
       if (!features.contains("fdo_optimize")) {
-        TextFormat.merge(""
-            + "feature {"
-            + "  name: 'fdo_optimize'"
-            + "  flag_set {"
-            + "    action: 'c-compile'"
-            + "    action: 'c++-compile'"
-            + "    flag_group {"
-            + "      flag: '-Xgcc-only=-fprofile-use=%{fdo_profile_path}'"
-            + "      flag: '-Xclang-only=-fprofile-instr-use=%{fdo_profile_path}'"
-            + "      flag: '-Xclang-only=-Wno-profile-instr-unprofiled'"
-            + "      flag: '-Xclang-only=-Wno-profile-instr-out-of-date'"
-            + "      flag: '-fprofile-correction'"
-            + "    }"
-            + "  }"
-            + "}",
+        TextFormat.merge(
+            ""
+                + "feature {"
+                + "  name: 'fdo_optimize'"
+                + "  provides: 'profile'"
+                + "  flag_set {"
+                + "    action: 'c-compile'"
+                + "    action: 'c++-compile'"
+                + "    expand_if_all_available: 'fdo_profile_path'"
+                + "    flag_group {"
+                + "      flag: '-Xgcc-only=-fprofile-use=%{fdo_profile_path}'"
+                + "      flag: '-Xclang-only=-fprofile-instr-use=%{fdo_profile_path}'"
+                + "      flag: '-Xclang-only=-Wno-profile-instr-unprofiled'"
+                + "      flag: '-Xclang-only=-Wno-profile-instr-out-of-date'"
+                + "      flag: '-fprofile-correction'"
+                + "    }"
+                + "  }"
+                + "}",
             toolchainBuilder);
       }
       if (!features.contains("autofdo")) {
-        TextFormat.merge(""
-            + "feature {"
-            + "  name: 'autofdo'"
-            + "  flag_set {"
-            + "    action: 'c-compile'"
-            + "    action: 'c++-compile'"
-            + "    flag_group {"
-            + "      flag: '-fauto-profile=%{fdo_profile_path}'"
-            + "      flag: '-fprofile-correction'"
-            + "    }"
-            + "  }"
-            + "}",
+        TextFormat.merge(
+            ""
+                + "feature {"
+                + "  name: 'autofdo'"
+                + "  provides: 'profile'"
+                + "  flag_set {"
+                + "    action: 'c-compile'"
+                + "    action: 'c++-compile'"
+                + "    expand_if_all_available: 'fdo_profile_path'"
+                + "    flag_group {"
+                + "      flag: '-fauto-profile=%{fdo_profile_path}'"
+                + "      flag: '-fprofile-correction'"
+                + "    }"
+                + "  }"
+                + "}",
             toolchainBuilder);
       }
       if (!features.contains("lipo")) {
-        TextFormat.merge(""
-            + "feature {"
-            + "  name: 'lipo'"
-            + "  flag_set {"
-            + "    action: 'c-compile'"
-            + "    action: 'c++-compile'"
-            + "    flag_group {"
-            + "      flag: '-fripa'"
-            + "    }"
-            + "  }"
-            + "}",
+        TextFormat.merge(
+            ""
+                + "feature {"
+                + "  name: 'lipo'"
+                + "  requires { feature: 'autofdo' }"
+                + "  requires { feature: 'fdo_optimize' }"
+                + "  requires { feature: 'fdo_instrument' }"
+                + "  flag_set {"
+                + "    action: 'c-compile'"
+                + "    action: 'c++-compile'"
+                + "    flag_group {"
+                + "      flag: '-fripa'"
+                + "    }"
+                + "  }"
+                + "}",
             toolchainBuilder);
       }
       if (!features.contains("coverage")) {
@@ -789,6 +801,7 @@ public class CppConfiguration extends BuildConfiguration.Fragment {
             ""
                 + "feature {"
                 + "  name: 'coverage'"
+                + "  provides: 'profile'"
                 + "  flag_set {"
                 + "    action: 'preprocess-assemble'"
                 + "    action: 'c-compile'"
diff --git a/src/main/java/com/google/devtools/build/lib/rules/cpp/FdoSupport.java b/src/main/java/com/google/devtools/build/lib/rules/cpp/FdoSupport.java
index a2339c2b2a..1ab6a8b5f4 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/cpp/FdoSupport.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/cpp/FdoSupport.java
@@ -44,7 +44,6 @@ import com.google.devtools.build.skyframe.SkyFunction;
 
 import java.io.IOException;
 import java.util.Collection;
-import java.util.HashSet;
 import java.util.zip.ZipException;
 
 /**
@@ -502,29 +501,6 @@ public class FdoSupport {
                 fdoRootExecPath.getPathString());
           }
         }
-      } else {
-        // TODO(bazel-team): Remove this workaround once the feature configuration
-        // supports per-file feature enabling.
-        // The feature configuration was created based on blaze options, which
-        // enabled the fdo optimize options since the fdoRoot was set.
-        // In this case the source file doesn't have an associated profile,
-        // so we need to disable these features so that we don't add the FDO options.
-        // However, the list of features is immutable and set on the CppModel.
-        // Create a new feature config here, enabling just what we want,
-        // and set it in this builder.
-        Collection<String> featureNames = cppConfiguration.getFeatures().getFeatureNames();
-        Collection<String> newFeatureNames = new HashSet<>();
-        for (String name : featureNames) {
-          if (featureConfiguration.isEnabled(name)) {
-            newFeatureNames.add(name);
-          }
-        }
-        newFeatureNames.remove(CppRuleClasses.FDO_OPTIMIZE);
-        newFeatureNames.remove(CppRuleClasses.AUTOFDO);
-        newFeatureNames.remove(CppRuleClasses.LIPO);
-        FeatureConfiguration newFeatureConfiguration =
-            cppConfiguration.getFeatures().getFeatureConfiguration(newFeatureNames);
-        builder.setFeatureConfiguration(newFeatureConfiguration);
       }
     }
   }