Support of using the absolute path profile for LLVM's Context Sensiti…

…ve FDO

This CL adds the support of using the absolute path profile in LLVM's Context
Sensitive FDO. The newly added option is
    --cs_fdo_absolute_path=<csfdo_profile>
The profile can be of the zip file containing the profile file, a raw or an
indexed LLVM profile file. Unlike --fdo_optimize, it will not accept a profile label.
Profile label should should use option --cs_fdo_profile.

RELNOTES: Add new options --cs_fdo_absolute_path= to support the absolute path
profile for LLVM's context-sensitive FDO.
PiperOrigin-RevId: 251252510

src/main/java/com/google/devtools/build/lib/rules/cpp/CppConfiguration.java

@@ -147,6 +147,8 @@ public String toString() {
   private final PathFragment fdoPath;
   private final Label fdoOptimizeLabel;
 
+  private final PathFragment csFdoAbsolutePath;
+
   private final ImmutableList<String> conlyopts;
 
   private final ImmutableList<String> copts;
@@ -197,13 +199,30 @@ static CppConfiguration create(CpuTransformer cpuTransformer, BuildOptions optio
       }
     }
 
+    PathFragment csFdoAbsolutePath = null;
+    if (cppOptions.csFdoAbsolutePathForBuild != null) {
+      csFdoAbsolutePath = PathFragment.create(cppOptions.csFdoAbsolutePathForBuild);
+      if (!csFdoAbsolutePath.isAbsolute()) {
+        throw new InvalidConfigurationException(
+            "Path of '"
+                + csFdoAbsolutePath.getPathString()
+                + "' in --cs_fdo_absolute_path is not an absolute path.");
+      }
+      try {
+        FileSystemUtils.checkBaseName(csFdoAbsolutePath.getBaseName());
+      } catch (IllegalArgumentException e) {
+        throw new InvalidConfigurationException(e);
+      }
+    }
+
     return new CppConfiguration(
         cppOptions.doNotUseCpuTransformer
             ? commonOptions.cpu
             : cpuTransformer.getTransformer().apply(commonOptions.cpu),
         Preconditions.checkNotNull(commonOptions.cpu),
         fdoPath,
         fdoProfileLabel,
+        csFdoAbsolutePath,
         ImmutableList.copyOf(cppOptions.conlyoptList),
         ImmutableList.copyOf(cppOptions.coptList),
         ImmutableList.copyOf(cppOptions.cxxoptList),
@@ -224,6 +243,7 @@ private CppConfiguration(
       String desiredCpu,
       PathFragment fdoPath,
       Label fdoOptimizeLabel,
+      PathFragment csFdoAbsolutePath,
       ImmutableList<String> conlyopts,
       ImmutableList<String> copts,
       ImmutableList<String> cxxopts,
@@ -239,6 +259,7 @@ private CppConfiguration(
     this.desiredCpu = desiredCpu;
     this.fdoPath = fdoPath;
     this.fdoOptimizeLabel = fdoOptimizeLabel;
+    this.csFdoAbsolutePath = csFdoAbsolutePath;
     this.conlyopts = conlyopts;
     this.copts = copts;
     this.cxxopts = cxxopts;
@@ -548,6 +569,10 @@ public String getCSFdoInstrument() {
     return cppOptions.csFdoInstrumentForBuild;
   }
 
+  public PathFragment getCSFdoAbsolutePath() {
+    return csFdoAbsolutePath;
+  }
+
   Label getFdoPrefetchHintsLabel() {
     if (isThisHostConfigurationDoNotUseWillBeRemovedFor129045294()) {
       // We don't want FDO in the host configuration

src/main/java/com/google/devtools/build/lib/rules/cpp/CppOptions.java

@@ -431,6 +431,17 @@ public String getFdoOptimize() {
               + "dumped at runtime.")
   public String csFdoInstrumentForBuild;
 
+  @Option(
+      name = "cs_fdo_absolute_path",
+      defaultValue = "null",
+      documentationCategory = OptionDocumentationCategory.OUTPUT_PARAMETERS,
+      effectTags = {OptionEffectTag.AFFECTS_OUTPUTS},
+      help =
+          "Use CSFDO profile information to optimize compilation. Specify the absolute path name "
+              + "of the zip file containing the profile file, a raw or an indexed "
+              + "LLVM profile file.")
+  public String csFdoAbsolutePathForBuild;
+
   @Option(
       name = "xbinary_fdo",
       defaultValue = "null",

src/main/java/com/google/devtools/build/lib/rules/cpp/FdoHelper.java

@@ -90,7 +90,10 @@ public static FdoContext getFdoContext(
       }
 
       Pair<FdoInputFile, Artifact> csFdoInputs = null;
-      if (cppConfiguration.getCSFdoProfileLabel() != null) {
+      PathFragment csFdoZip = cppConfiguration.getCSFdoAbsolutePath();
+      if (csFdoZip != null) {
+        csFdoInputFile = FdoInputFile.fromAbsolutePath(csFdoZip);
+      } else if (cppConfiguration.getCSFdoProfileLabel() != null) {
         csFdoInputs = getFdoInputs(ruleContext, attributes.getCSFdoProfileProvider());
       }
       if (csFdoInputs != null) {

src/test/java/com/google/devtools/build/lib/rules/cpp/CcToolchainTest.java

@@ -454,6 +454,24 @@ public void testFdoOptimizeNotCompatibleWithCoverage() throws Exception {
     assertContainsEvent("coverage mode is not compatible with FDO optimization");
   }
 
+  @Test
+  public void testCSFdoRejectRelativePath() throws Exception {
+    reporter.removeHandler(failFastHandler);
+    scratch.file("a/BUILD", "cc_toolchain_alias(name = 'b')");
+    scratch.file("a/profile.profdata", "");
+    scratch.file("a/csprofile.profdata", "");
+    Exception e =
+        assertThrows(
+            Exception.class,
+            () ->
+                useConfiguration(
+                    "-c",
+                    "opt",
+                    "--fdo_optimize=a/profile.profdata",
+                    "--cs_fdo_absolute_path=a/csprofile.profdata"));
+    assertThat(e).hasMessageThat().contains("in --cs_fdo_absolute_path is not an absolute path");
+  }
+
   @Test
   public void testXFdoOptimizeNotProvider() throws Exception {
     reporter.removeHandler(failFastHandler);