Remove lookupSymbol() and have all callers use SymbolInfo::lookup() instead (#62552)

Author: grynspan

stdlib/public/SwiftShims/swift/shims/MetadataSections.h

@@ -53,8 +53,8 @@ struct MetadataSections {
   /// reported when the section was registered with the Swift runtime.
   ///
   /// The value of this field is equivalent to the value of
-  /// \c SymbolInfo::baseAddress as returned from \c lookupSymbol() for a symbol
-  /// in the image that contains these sections.
+  /// \c SymbolInfo::baseAddress as returned from \c SymbolInfo::lookup() for a
+  /// symbol in the image that contains these sections.
   ///
   /// For Mach-O images, set this field to \c __dso_handle (i.e. the Mach header
   /// for the image.) For ELF images, set it to \c __dso_handle (the runtime

stdlib/public/runtime/Errors.cpp

@@ -144,18 +144,16 @@ static bool getSymbolNameAddr(llvm::StringRef libraryName,
 void swift::dumpStackTraceEntry(unsigned index, void *framePC,
                                 bool shortOutput) {
 #if SWIFT_STDLIB_SUPPORTS_BACKTRACE_REPORTING && SWIFT_STDLIB_HAS_DLADDR
-  SymbolInfo syminfo;
-
-  // 0 is failure for lookupSymbol
-  if (0 == lookupSymbol(framePC, &syminfo)) {
+  auto syminfo = SymbolInfo::lookup(framePC);
+  if (!syminfo.has_value()) {
     return;
   }
 
-  // If lookupSymbol succeeded then fileName is non-null. Thus, we find the
+  // If SymbolInfo:lookup succeeded then fileName is non-null. Thus, we find the
   // library name here. Avoid using StringRef::rsplit because its definition
   // is not provided in the header so that it requires linking with
   // libSupport.a.
-  llvm::StringRef libraryName{syminfo.getFilename()};
+  llvm::StringRef libraryName{syminfo->getFilename()};
   libraryName = libraryName.substr(libraryName.rfind('/')).substr(1);
 
   // Next we get the symbol name that we are going to use in our backtrace.
@@ -165,12 +163,12 @@ void swift::dumpStackTraceEntry(unsigned index, void *framePC,
   // we just get HexAddr + 0.
   uintptr_t symbolAddr = uintptr_t(framePC);
   bool foundSymbol =
-      getSymbolNameAddr(libraryName, syminfo, symbolName, symbolAddr);
+      getSymbolNameAddr(libraryName, syminfo.value(), symbolName, symbolAddr);
   ptrdiff_t offset = 0;
   if (foundSymbol) {
     offset = ptrdiff_t(uintptr_t(framePC) - symbolAddr);
   } else {
-    auto baseAddress = syminfo.getBaseAddress();
+    auto baseAddress = syminfo->getBaseAddress();
     offset = ptrdiff_t(uintptr_t(framePC) - uintptr_t(baseAddress));
     symbolAddr = uintptr_t(framePC);
     symbolName = "<unavailable>";

stdlib/public/runtime/ImageInspectionCommon.cpp

@@ -64,9 +64,9 @@ static void fixupMetadataSectionBaseAddress(swift::MetadataSections *sections) {
   if (fixupNeeded) {
     // We need to fix up the base address. We'll need a known-good address in
     // the same image: `sections` itself will work nicely.
-    swift::SymbolInfo symbolInfo;
-    if (lookupSymbol(sections, &symbolInfo) && symbolInfo.getBaseAddress()) {
-        sections->baseAddress.store(symbolInfo.getBaseAddress(),
+    auto symbolInfo = SymbolInfo::lookup(sections);
+    if (symbolInfo.has_value() && symbolInfo->getBaseAddress()) {
+        sections->baseAddress.store(symbolInfo->getBaseAddress(),
                                     std::memory_order_relaxed);
     }
   }
@@ -190,10 +190,9 @@ const swift::MetadataSections *swift_getMetadataSection(size_t index) {
 SWIFT_RUNTIME_EXPORT
 const char *
 swift_getMetadataSectionName(const swift::MetadataSections *section) {
-  swift::SymbolInfo info;
-  if (lookupSymbol(section, &info)) {
-    if (info.getFilename()) {
-      return info.getFilename();
+  if (auto info = SymbolInfo::lookup(section)) {
+    if (info->getFilename()) {
+      return info->getFilename();
     }
   }
   return "";
@@ -203,9 +202,8 @@ SWIFT_RUNTIME_EXPORT
 void swift_getMetadataSectionBaseAddress(const swift::MetadataSections *section,
                                          void const **out_actual,
                                          void const **out_expected) {
-  swift::SymbolInfo info;
-  if (lookupSymbol(section, &info)) {
-    *out_actual = info.getBaseAddress();
+  if (auto info = SymbolInfo::lookup(section)) {
+    *out_actual = info->getBaseAddress();
   } else {
     *out_actual = nullptr;
   }

stdlib/public/runtime/MetadataLookup.cpp

@@ -1105,9 +1105,8 @@ _gatherGenericParameters(const ContextDescriptor *context,
 
       str += "_gatherGenericParameters: context: ";
 
-      SymbolInfo contextInfo;
-      if (lookupSymbol(context, &contextInfo)) {
-        str += contextInfo.getSymbolName();
+      if (auto contextInfo = SymbolInfo::lookup(context)) {
+        str += contextInfo->getSymbolName();
         str += " ";
       }
 

stdlib/public/runtime/ProtocolConformance.cpp

@@ -124,12 +124,13 @@ static const char *class_getName(const ClassMetadata* type) {
 }
 
 template<> void ProtocolConformanceDescriptor::dump() const {
-  SymbolInfo info;
+  llvm::Optional<SymbolInfo> info;
   auto symbolName = [&](const void *addr) -> const char * {
-    int ok = lookupSymbol(addr, &info);
-    if (!ok || !info.getSymbolName())
-      return "<unknown addr>";
-    return info.getSymbolName();
+    info = SymbolInfo::lookup(addr);
+    if (info.has_value() && info->getSymbolName()) {
+      return info->getSymbolName();
+    }
+    return "<unknown addr>";
   };
 
   switch (auto kind = getTypeKind()) {

stdlib/public/runtime/ReflectionMirror.cpp

@@ -1116,11 +1116,12 @@ id swift_reflectionMirror_quickLookObject(OpaqueValue *value, const Metadata *T)
 
 SWIFT_CC(swift) SWIFT_RUNTIME_STDLIB_INTERNAL
 const char *swift_keyPath_copySymbolName(void *address) {
-  SymbolInfo info;
-  if (lookupSymbol(address, &info) && info.getSymbolName()) {
-    return strdup(info.getSymbolName());
+  if (auto info = SymbolInfo::lookup(address)) {
+    if (info->getSymbolName()) {
+      return strdup(info->getSymbolName());
+    }
   }
-  return 0;
+  return nullptr;
 }
 
 SWIFT_CC(swift) SWIFT_RUNTIME_STDLIB_INTERNAL

stdlib/public/runtime/SymbolInfo.h

@@ -76,27 +76,6 @@ struct SymbolInfo {
   static llvm::Optional<SymbolInfo> lookup(const void *address);
 };
 
-/// Look up a symbol by address and store the result in a locally-declared
-/// \c SymbolInfo value.
-///
-/// \param address The address where the symbol is located.
-/// \param outInfo On successful return, populated with information about the
-///   symbol at \a address. On failure, unspecified.
-///
-/// \returns On success, a non-zero integer. On failure, zero.
-///
-/// \note This function will be replaced with \c SymbolInfo::lookup() in a
-///   future update.
-static inline int lookupSymbol(const void *address, SymbolInfo *outInfo) {
-  auto info = SymbolInfo::lookup(address);
-  if (info.has_value()) {
-    *outInfo = info.value();
-    return 1;
-  } else {
-    return 0;
-  }
-}
-
 } // end namespace swift
 
 #endif