[lldb] Log when we cannot find an equivalent for a gdb register type

[DavidSpickett]

Summary

This happens if the type is described elsewhere in target xml as a
<flags> or <struct>.

Also hardcode the function names into the log messages because
if you use FUNCTION in a lambda you just get "operator()".

[clayborg]

So you can use

__PRETTY_FUNCTION__

in log messages if you want to get a demangled name for a C++ function, but that includes args, so it might be too verbose in a log message.

[DavidSpickett]

I didn't know about that, it's exactly what I wanted - if it worked with msvc https://godbolt.org/z/cqYf3c39n.

It is used in lldb but only in tests we know will be compiled with clang (well, we assume) and some Mac OS native code which will be clang compiled.

lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.cpp

struct GdbServerTargetInfo {
   RegisterSetMap reg_set_map;
 };
 
 bool ParseRegisters(XMLNode feature_node, GdbServerTargetInfo &target_info,
                     std::vector<DynamicRegisterInfo::Register> &registers) {
   if (!feature_node)
     return false;
 
+  Log *log(GetLog(GDBRLog::Process));
+
   feature_node.ForEachChildElementWithName(
-      "reg", [&target_info, &registers](const XMLNode &reg_node) -> bool {
+      "reg", [&target_info, &registers, log](const XMLNode &reg_node) -> bool {
         std::string gdb_group;
         std::string gdb_type;
         DynamicRegisterInfo::Register reg_info;
         bool encoding_set = false;
         bool format_set = false;
 
         // FIXME: we're silently ignoring invalid data here
         reg_node.ForEachAttribute([&target_info, &gdb_group, &gdb_type,
-                                   &encoding_set, &format_set, &reg_info](
-                                      const llvm::StringRef &name,
+                                   &encoding_set, &format_set, &reg_info,
+                                   log](const llvm::StringRef &name,
                                         const llvm::StringRef &value) -> bool {
           if (name == "name") {
             reg_info.name.SetString(value);
           } else if (name == "bitsize") {
             if (llvm::to_integer(value, reg_info.byte_size))
               reg_info.byte_size =
                   llvm::divideCeil(reg_info.byte_size, CHAR_BIT);
           } else if (name == "type") {
             gdb_type = value.str();
feature_node.ForEachChildElementWithName(
             reg_info.regnum_generic = Args::StringToGenericRegister(value);
           } else if (name == "value_regnums") {
             SplitCommaSeparatedRegisterNumberString(value, reg_info.value_regs,
                                                     0);
           } else if (name == "invalidate_regnums") {
             SplitCommaSeparatedRegisterNumberString(
                 value, reg_info.invalidate_regs, 0);
           } else {
-            Log *log(GetLog(GDBRLog::Process));
             LLDB_LOGF(log,
-                      "ProcessGDBRemote::%s unhandled reg attribute %s = %s",
-                      __FUNCTION__, name.data(), value.data());
+                      "ProcessGDBRemote::ParseRegisters unhandled reg "
+                      "attribute %s = %s",
+                      name.data(), value.data());
           }
           return true; // Keep iterating through all attributes
         });
 
         if (!gdb_type.empty() && !(encoding_set || format_set)) {
           if (llvm::StringRef(gdb_type).startswith("int")) {
             reg_info.format = eFormatHex;
             reg_info.encoding = eEncodingUint;
           } else if (gdb_type == "data_ptr" || gdb_type == "code_ptr") {
             reg_info.format = eFormatAddressInfo;
             reg_info.encoding = eEncodingUint;
           } else if (gdb_type == "float") {
             reg_info.format = eFormatFloat;
             reg_info.encoding = eEncodingIEEE754;
           } else if (gdb_type == "aarch64v" ||
                      llvm::StringRef(gdb_type).startswith("vec") ||
                      gdb_type == "i387_ext" || gdb_type == "uint128") {
             // lldb doesn't handle 128-bit uints correctly (for ymm*h), so treat
             // them as vector (similarly to xmm/ymm)
             reg_info.format = eFormatVectorOfUInt8;
             reg_info.encoding = eEncodingVector;
+          } else {
+            LLDB_LOGF(
+                log,
+                "ProcessGDBRemote::ParseRegisters Could not determine lldb"
+                "format and encoding for gdb type %s",
+                gdb_type.c_str());
           }
         }
 
         // Only update the register set name if we didn't get a "reg_set"
         // attribute. "set_name" will be empty if we didn't have a "reg_set"
         // attribute.
         if (!reg_info.set_name) {
           if (!gdb_group.empty()) {
             reg_info.set_name.SetCString(gdb_group.c_str());
           } else {
             // If no register group name provided anywhere,
             // we'll create a 'general' register set
             reg_info.set_name.SetCString("general");
           }
         }
 
         if (reg_info.byte_size == 0) {
-          Log *log(GetLog(GDBRLog::Process));
           LLDB_LOGF(log,
                     "ProcessGDBRemote::%s Skipping zero bitsize register %s",
                     __FUNCTION__, reg_info.name.AsCString());
         } else
           registers.push_back(reg_info);
 
         return true; // Keep iterating through all "reg" elements
       });