[llvm][orc] Consider other ELF init sections as well

[Mogball]

Summary

ELF object files can contain .ctors and .dtors sections that also
participate as initializers.

[Mogball]

Don't include .rela sections

[Mogball]

@lhames PTAL

[lhames]

Mostly looks good, but should .dtors be included as an init section? I don't think ELFNixPlatform has any special case logic for .dtors yet, which might lead to functions in .dtors being run immediately upon load.

It may take some changes on the ELFNixPlatform side to make .dtors work.

[Mogball]

I don't think ELFNixPlatform has any special case logic for .dtors yet, which might lead to functions in .dtors being run immediately upon load.

You are right. I double-checked this and it is causing the dtors to run upon load. I'll comment dtors out and file an issue to fix this in ELFNixPlatform. Thanks for taking a look!

[Mogball]

drop fini and dtors from init sections

[lhames]

LGTM. Thanks @Mogball!

llvm/include/llvm/ExecutionEngine/Orc/Shared/ObjectFormats.h

 extern StringRef MachOThreadBSSSectionName;
 extern StringRef MachOThreadDataSectionName;
 extern StringRef MachOThreadVarsSectionName;
 
 extern StringRef MachOInitSectionNames[19];
 
 // ELF section names.
 extern StringRef ELFEHFrameSectionName;
+
 extern StringRef ELFInitArrayFuncSectionName;
+extern StringRef ELFInitFuncSectionName;
+extern StringRef ELFFiniArrayFuncSectionName;
+extern StringRef ELFFiniFuncSectionName;
+extern StringRef ELFCtorArrayFuncSectionName;
+extern StringRef ELFDtorArrayFuncSectionName;
+
+extern StringRef ELFInitSectionNames[3];
 
 extern StringRef ELFThreadBSSSectionName;
 extern StringRef ELFThreadDataSectionName;
 
 bool isMachOInitializerSection(StringRef SegName, StringRef SecName);
 bool isMachOInitializerSection(StringRef QualifiedName);
 
 bool isELFInitializerSection(StringRef SecName);
 
 bool isCOFFInitializerSection(StringRef Name);
 
 } // end namespace orc
 } // end namespace llvm
 
 #endif // LLVM_EXECUTIONENGINE_ORC_SHARED_MEMORYFLAGS_H

llvm/lib/ExecutionEngine/Orc/Shared/ObjectFormats.cpp

StringRef MachOInitSectionNames[19] = {
     MachOObjCMethTypeSectionName,  MachOObjCNLCatListSectionName,
     MachOObjCSelRefsSectionName,   MachOSwift5ProtoSectionName,
     MachOSwift5ProtosSectionName,  MachOSwift5TypesSectionName,
     MachOSwift5TypeRefSectionName, MachOSwift5FieldMetadataSectionName,
     MachOSwift5EntrySectionName,
 };
 
 StringRef ELFEHFrameSectionName = ".eh_frame";
+
 StringRef ELFInitArrayFuncSectionName = ".init_array";
+StringRef ELFInitFuncSectionName = ".init";
+StringRef ELFFiniArrayFuncSectionName = ".fini_array";
+StringRef ELFFiniFuncSectionName = ".fini";
+StringRef ELFCtorArrayFuncSectionName = ".ctors";
+StringRef ELFDtorArrayFuncSectionName = ".dtors";
+
+StringRef ELFInitSectionNames[3]{
+    ELFInitArrayFuncSectionName,
+    ELFInitFuncSectionName,
+    ELFCtorArrayFuncSectionName,
+};
 
 StringRef ELFThreadBSSSectionName = ".tbss";
 StringRef ELFThreadDataSectionName = ".tdata";
 
 bool isMachOInitializerSection(StringRef SegName, StringRef SecName) {
   for (auto &InitSection : MachOInitSectionNames) {
     // Loop below assumes all MachO init sectios have a length-6
     // segment name.
     assert(InitSection[6] == ',' && "Init section seg name has length != 6");
     if (InitSection.starts_with(SegName) && InitSection.substr(7) == SecName)
       return true;
   }
   return false;
 }
 
 bool isMachOInitializerSection(StringRef QualifiedName) {
   for (auto &InitSection : MachOInitSectionNames)
     if (InitSection == QualifiedName)
       return true;
   return false;
 }
 
 bool isELFInitializerSection(StringRef SecName) {
-  if (SecName.consume_front(ELFInitArrayFuncSectionName) &&
-      (SecName.empty() || SecName[0] == '.'))
+  for (StringRef InitSection : ELFInitSectionNames) {
+    StringRef Name = SecName;
+    if (Name.consume_front(InitSection) && (Name.empty() || Name[0] == '.'))
       return true;
+  }
   return false;
 }
 
 bool isCOFFInitializerSection(StringRef SecName) {
   return SecName.startswith(".CRT");
 }
 
 } // namespace orc
 } // namespace llvm

llvm/unittests/ExecutionEngine/Orc/ObjectFormatsTest.cpp

TEST(ObjectFormatsTest, MachOInitializerSections) {
   EXPECT_TRUE(isMachOInitializerSection("__TEXT,__swift5_types"));
   EXPECT_FALSE(isMachOInitializerSection("__DATA,__not_an_init_sec"));
 }
 
 TEST(ObjectFormatsTest, ELFInitializerSections) {
   EXPECT_TRUE(isELFInitializerSection(".init_array"));
   EXPECT_TRUE(isELFInitializerSection(".init_array.0"));
   EXPECT_FALSE(isELFInitializerSection(".text"));
+  EXPECT_TRUE(isELFInitializerSection(".ctors.0"));
 }
 
 } // end anonymous namespace