[llvm-objdump/mac] Add new function starts print mode

This updates the `--function-starts` argument to now accept 3 different
modes, `addrs` for just printing the addresses of the function starts
(previous behavior), `names` for just printing the names of the function
starts, and `both` to print them both side by side.

In general if you're debugging function starts issues it's useful to see
the symbol name alongside the address. This also mirrors Apple's
`dyldinfo -function_starts` command which prints both.

Differential Revision: https://reviews.llvm.org/D119050

1 files changed, 46 insertions, 10 deletions

diff --git a/llvm/tools/llvm-objdump/MachODump.cpp b/llvm/tools/llvm-objdump/MachODump.cpp
index 4637b09..3164159 100644
--- a/llvm/tools/llvm-objdump/MachODump.cpp
+++ b/llvm/tools/llvm-objdump/MachODump.cpp
@@ -78,7 +78,8 @@ bool objdump::UniversalHeaders;
 static bool ArchiveMemberOffsets;
 bool objdump::IndirectSymbols;
 bool objdump::DataInCode;
-bool objdump::FunctionStarts;
+FunctionStartsMode objdump::FunctionStartsType =
+    objdump::FunctionStartsMode::None;
 bool objdump::LinkOptHints;
 bool objdump::InfoPlist;
 bool objdump::ChainedFixups;
@@ -112,7 +113,15 @@ void objdump::parseMachOOptions(const llvm::opt::InputArgList &InputArgs) {
   ArchiveMemberOffsets = InputArgs.hasArg(OBJDUMP_archive_member_offsets);
   IndirectSymbols = InputArgs.hasArg(OBJDUMP_indirect_symbols);
   DataInCode = InputArgs.hasArg(OBJDUMP_data_in_code);
-  FunctionStarts = InputArgs.hasArg(OBJDUMP_function_starts);
+  if (const opt::Arg *A = InputArgs.getLastArg(OBJDUMP_function_starts_EQ)) {
+    FunctionStartsType = StringSwitch<FunctionStartsMode>(A->getValue())
+                             .Case("addrs", FunctionStartsMode::Addrs)
+                             .Case("names", FunctionStartsMode::Names)
+                             .Case("both", FunctionStartsMode::Both)
+                             .Default(FunctionStartsMode::None);
+    if (FunctionStartsType == FunctionStartsMode::None)
+      invalidArgValue(A);
+  }
   LinkOptHints = InputArgs.hasArg(OBJDUMP_link_opt_hints);
   InfoPlist = InputArgs.hasArg(OBJDUMP_info_plist);
   ChainedFixups = InputArgs.hasArg(OBJDUMP_chained_fixups);
@@ -1080,12 +1089,39 @@ static void PrintFunctionStarts(MachOObjectFile *O) {
     }
   }
 
+  DenseMap<uint64_t, StringRef> SymbolNames;
+  if (FunctionStartsType == FunctionStartsMode::Names ||
+      FunctionStartsType == FunctionStartsMode::Both) {
+    for (SymbolRef Sym : O->symbols()) {
+      if (Expected<uint64_t> Addr = Sym.getAddress()) {
+        if (Expected<StringRef> Name = Sym.getName()) {
+          SymbolNames[*Addr] = *Name;
+        }
+      }
+    }
+  }
+
   for (uint64_t S : FunctionStarts) {
     uint64_t Addr = BaseSegmentAddress + S;
-    if (O->is64Bit())
-      outs() << format("%016" PRIx64, Addr) << "\n";
-    else
-      outs() << format("%08" PRIx32, static_cast<uint32_t>(Addr)) << "\n";
+    if (FunctionStartsType == FunctionStartsMode::Names) {
+      auto It = SymbolNames.find(Addr);
+      if (It != SymbolNames.end())
+        outs() << It->second << "\n";
+    } else {
+      if (O->is64Bit())
+        outs() << format("%016" PRIx64, Addr);
+      else
+        outs() << format("%08" PRIx32, static_cast<uint32_t>(Addr));
+
+      if (FunctionStartsType == FunctionStartsMode::Both) {
+        auto It = SymbolNames.find(Addr);
+        if (It != SymbolNames.end())
+          outs() << " " << It->second;
+        else
+          outs() << " ?";
+      }
+      outs() << "\n";
+    }
   }
 }
 
@@ -2111,9 +2147,9 @@ static void ProcessMachO(StringRef Name, MachOObjectFile *MachOOF,
   // UniversalHeaders or ArchiveHeaders.
   if (Disassemble || Relocations || PrivateHeaders || ExportsTrie || Rebase ||
       Bind || SymbolTable || LazyBind || WeakBind || IndirectSymbols ||
-      DataInCode || FunctionStarts || LinkOptHints || ChainedFixups ||
-      DyldInfo || DylibsUsed || DylibId || Rpaths || ObjcMetaData ||
-      (!FilterSections.empty())) {
+      DataInCode || FunctionStartsType != FunctionStartsMode::None ||
+      LinkOptHints || ChainedFixups || DyldInfo || DylibsUsed || DylibId ||
+      Rpaths || ObjcMetaData || (!FilterSections.empty())) {
     if (LeadingHeaders) {
       outs() << Name;
       if (!ArchiveMemberName.empty())
@@ -2168,7 +2204,7 @@ static void ProcessMachO(StringRef Name, MachOObjectFile *MachOOF,
     PrintIndirectSymbols(MachOOF, Verbose);
   if (DataInCode)
     PrintDataInCodeTable(MachOOF, Verbose);
-  if (FunctionStarts)
+  if (FunctionStartsType != FunctionStartsMode::None)
     PrintFunctionStarts(MachOOF);
   if (LinkOptHints)
     PrintLinkOptHints(MachOOF);