Add functionality that returns correct reflection section name for different object files (Mach-O, ELF, COFF)

include/swift/ABI/ObjectFile.h

@@ -0,0 +1,99 @@
+//===--- ObjectFile.h - Object File Related Information ------*- C++ -*-===//
+//
+// Object File related data structures.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef SWIFT_ABI_OBJECTFILE_H
+#define SWIFT_ABI_OBJECTFILE_H
+
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/ADT/StringRef.h"
+
+namespace swift {
+
+/// Represents the six reflection sections used by Swift
+enum ReflectionSectionKind : uint8_t {
+  fieldmd,
+  assocty,
+  builtin,
+  capture,
+  typeref,
+  reflstr
+};
+
+/// Abstract base class responsible for providing the correct reflection section
+/// string identifier for a given object file type (Mach-O, ELF, COFF).
+class SwiftObjectFileFormat {
+public:
+  virtual ~SwiftObjectFileFormat() {}
+  virtual llvm::StringRef getSectionName(ReflectionSectionKind section) = 0;
+};
+
+/// Responsible for providing the Mach-O reflection section identifiers.
+class SwiftObjectFileFormatMachO : SwiftObjectFileFormat {
+public:
+  llvm::StringRef getSectionName(ReflectionSectionKind section) override {
+    switch (section) {
+    case fieldmd:
+      return "__swift5_fieldmd";
+    case assocty:
+      return "__swift5_assocty";
+    case builtin:
+      return "__swift5_builtin";
+    case capture:
+      return "__swift5_capture";
+    case typeref:
+      return "__swift5_typeref";
+    case reflstr:
+      return "__swift5_reflstr";
+    }
+    llvm_unreachable("Section type not found.");
+  }
+};
+
+/// Responsible for providing the ELF reflection section identifiers.
+class SwiftObjectFileFormatELF : SwiftObjectFileFormat {
+public:
+  llvm::StringRef getSectionName(ReflectionSectionKind section) override {
+    switch (section) {
+    case fieldmd:
+      return "swift5_fieldmd";
+    case assocty:
+      return "swift5_assocty";
+    case builtin:
+      return "swift5_builtin";
+    case capture:
+      return "swift5_capture";
+    case typeref:
+      return "swift5_typeref";
+    case reflstr:
+      return "swift5_reflstr";
+    }
+    llvm_unreachable("Section type not found.");
+  }
+};
+
+/// Responsible for providing the COFF reflection section identifiers
+class SwiftObjectFileFormatCOFF : SwiftObjectFileFormat {
+public:
+  llvm::StringRef getSectionName(ReflectionSectionKind section) override {
+    switch (section) {
+    case fieldmd:
+      return ".sw5flmd";
+    case assocty:
+      return ".sw5asty";
+    case builtin:
+      return ".sw5bltn";
+    case capture:
+      return ".sw5cptr";
+    case typeref:
+      return ".sw5tyrf";
+    case reflstr:
+      return ".sw5rfst";
+    }
+    llvm_unreachable("Section  not found.");
+  }
+};
+} // namespace swift
+#endif // SWIFT_ABI_OBJECTFILE_H

include/swift/Reflection/ReflectionContext.h

@@ -24,6 +24,7 @@
 #include "llvm/Object/COFF.h"
 
 #include "swift/ABI/Enum.h"
+#include "swift/ABI/ObjectFile.h"
 #include "swift/Remote/MemoryReader.h"
 #include "swift/Remote/MetadataReader.h"
 #include "swift/Reflection/Records.h"
@@ -210,12 +211,12 @@ class ReflectionContext
     auto SectBuf = this->getReader().readBytes(RemoteAddress(RangeStart),
                                                RangeEnd - RangeStart);
 
-    auto findMachOSectionByName = [&](std::string Name)
+    auto findMachOSectionByName = [&](llvm::StringRef Name)
         -> std::pair<RemoteRef<void>, uint64_t> {
       for (unsigned I = 0; I < NumSect; ++I) {
         auto S = reinterpret_cast<typename T::Section *>(
             SectionsBuf + (I * sizeof(typename T::Section)));
-        if (strncmp(S->sectname, Name.c_str(), strlen(Name.c_str())) != 0)
+        if (strncmp(S->sectname, Name.data(), strlen(Name.data())) != 0)
           continue;
         auto RemoteSecStart = S->addr + Slide;
         auto SectBufData = reinterpret_cast<const char *>(SectBuf.get());
@@ -228,12 +229,19 @@ class ReflectionContext
       return {nullptr, 0};
     };
 
-    auto FieldMdSec = findMachOSectionByName("__swift5_fieldmd");
-    auto AssocTySec = findMachOSectionByName("__swift5_assocty");
-    auto BuiltinTySec = findMachOSectionByName("__swift5_builtin");
-    auto CaptureSec = findMachOSectionByName("__swift5_capture");
-    auto TypeRefMdSec = findMachOSectionByName("__swift5_typeref");
-    auto ReflStrMdSec = findMachOSectionByName("__swift5_reflstr");
+    SwiftObjectFileFormatMachO ObjectFileFormat;
+    auto FieldMdSec = findMachOSectionByName(
+        ObjectFileFormat.getSectionName(ReflectionSectionKind::fieldmd));
+    auto AssocTySec = findMachOSectionByName(
+        ObjectFileFormat.getSectionName(ReflectionSectionKind::assocty));
+    auto BuiltinTySec = findMachOSectionByName(
+        ObjectFileFormat.getSectionName(ReflectionSectionKind::builtin));
+    auto CaptureSec = findMachOSectionByName(
+        ObjectFileFormat.getSectionName(ReflectionSectionKind::capture));
+    auto TypeRefMdSec = findMachOSectionByName(
+        ObjectFileFormat.getSectionName(ReflectionSectionKind::typeref));
+    auto ReflStrMdSec = findMachOSectionByName(
+        ObjectFileFormat.getSectionName(ReflectionSectionKind::reflstr));
 
     if (FieldMdSec.first == nullptr &&
         AssocTySec.first == nullptr &&
@@ -330,12 +338,19 @@ class ReflectionContext
       return {nullptr, 0};
     };
 
-    auto CaptureSec = findCOFFSectionByName(".sw5cptr");
-    auto TypeRefMdSec = findCOFFSectionByName(".sw5tyrf");
-    auto FieldMdSec = findCOFFSectionByName(".sw5flmd");
-    auto AssocTySec = findCOFFSectionByName(".sw5asty");
-    auto BuiltinTySec = findCOFFSectionByName(".sw5bltn");
-    auto ReflStrMdSec = findCOFFSectionByName(".sw5rfst");
+    SwiftObjectFileFormatCOFF ObjectFileFormat;
+    auto FieldMdSec = findCOFFSectionByName(
+        ObjectFileFormat.getSectionName(ReflectionSectionKind::fieldmd));
+    auto AssocTySec = findCOFFSectionByName(
+        ObjectFileFormat.getSectionName(ReflectionSectionKind::assocty));
+    auto BuiltinTySec = findCOFFSectionByName(
+        ObjectFileFormat.getSectionName(ReflectionSectionKind::builtin));
+    auto CaptureSec = findCOFFSectionByName(
+        ObjectFileFormat.getSectionName(ReflectionSectionKind::capture));
+    auto TypeRefMdSec = findCOFFSectionByName(
+        ObjectFileFormat.getSectionName(ReflectionSectionKind::typeref));
+    auto ReflStrMdSec = findCOFFSectionByName(
+        ObjectFileFormat.getSectionName(ReflectionSectionKind::reflstr));
 
     if (FieldMdSec.first == nullptr &&
         AssocTySec.first == nullptr &&
@@ -424,7 +439,7 @@ class ReflectionContext
     auto StrTabBuf = this->getReader().readBytes(StrTabStart, StrTabSize);
     auto StrTab = reinterpret_cast<const char *>(StrTabBuf.get());
 
-    auto findELFSectionByName = [&](std::string Name)
+    auto findELFSectionByName = [&](llvm::StringRef Name)
         -> std::pair<RemoteRef<void>, uint64_t> {
       // Now for all the sections, find their name.
       for (const typename T::Section *Hdr : SecHdrVec) {
@@ -444,12 +459,19 @@ class ReflectionContext
       return {nullptr, 0};
     };
 
-    auto FieldMdSec = findELFSectionByName("swift5_fieldmd");
-    auto AssocTySec = findELFSectionByName("swift5_assocty");
-    auto BuiltinTySec = findELFSectionByName("swift5_builtin");
-    auto CaptureSec = findELFSectionByName("swift5_capture");
-    auto TypeRefMdSec = findELFSectionByName("swift5_typeref");
-    auto ReflStrMdSec = findELFSectionByName("swift5_reflstr");
+    SwiftObjectFileFormatELF ObjectFileFormat;
+    auto FieldMdSec = findELFSectionByName(
+        ObjectFileFormat.getSectionName(ReflectionSectionKind::fieldmd));
+    auto AssocTySec = findELFSectionByName(
+        ObjectFileFormat.getSectionName(ReflectionSectionKind::assocty));
+    auto BuiltinTySec = findELFSectionByName(
+        ObjectFileFormat.getSectionName(ReflectionSectionKind::builtin));
+    auto CaptureSec = findELFSectionByName(
+        ObjectFileFormat.getSectionName(ReflectionSectionKind::capture));
+    auto TypeRefMdSec = findELFSectionByName(
+        ObjectFileFormat.getSectionName(ReflectionSectionKind::typeref));
+    auto ReflStrMdSec = findELFSectionByName(
+        ObjectFileFormat.getSectionName(ReflectionSectionKind::reflstr));
 
     // We succeed if at least one of the sections is present in the
     // ELF executable.