[llvm-objdump] Add -demangle (-C) option

Differential Revision: https://reviews.llvm.org/D49043

llvm-svn: 336816

llvm/test/tools/llvm-objdump/disassemble-demangle.test

@@ -0,0 +1,47 @@
+# RUN: yaml2obj %s > %t
+# RUN: llvm-objdump -d -C %t | FileCheck --check-prefix=DEMANGLE %s
+# RUN: llvm-objdump -d --demangle=itanium %t | FileCheck --check-prefix=DEMANGLE %s
+# RUN: llvm-objdump -d %t | FileCheck --check-prefix=NO-DEMANGLE %s
+# RUN: llvm-objdump -d --demangle=none %t | FileCheck --check-prefix=NO-DEMANGLE %s
+# RUN: llvm-objdump -d -C=wrong-style %t 2>&1 | FileCheck --check-prefix=BAD-STYLE %s
+
+!ELF
+FileHeader:
+  Class:           ELFCLASS64
+  Data:            ELFDATA2LSB
+  Type:            ET_EXEC
+  Machine:         EM_X86_64
+Sections:
+  - Name:            .text1
+    Type:            SHT_PROGBITS
+    Flags:           [ SHF_ALLOC, SHF_EXECINSTR ]
+    Address:         0x1000
+    AddressAlign:    0x0000000000000010
+    Content:         "0000000000000000"
+  - Name:            .text2
+    Type:            SHT_PROGBITS
+    Flags:           [ SHF_ALLOC, SHF_EXECINSTR ]
+    Address:         0x1010
+    AddressAlign:    0x0000000000000010
+    Content:         "0000000000000000"
+Symbols:
+  Local:
+    - Name:     _Z3fooi
+      Type:     STT_FUNC
+      Section:  .text1
+      Value:    0x1000
+    - Name:     _Z3foov
+      Type:     STT_FUNC
+      Section:  .text2
+      Value:    0x1010
+
+# We just want to check that the symbols are demangled
+# DEMANGLE: foo(int)
+# DEMANGLE: foo()
+
+# NO-DEMANGLE: _Z3fooi
+# NO-DEMANGLE: _Z3foov
+
+# BAD-STYLE: warning: Unsupported demangling style.
+# BAD-STYLE: _Z3fooi
+# BAD-STYLE: _Z3foov

llvm/tools/llvm-objdump/llvm-objdump.cpp

@@ -25,6 +25,7 @@
 #include "llvm/CodeGen/FaultMaps.h"
 #include "llvm/DebugInfo/DWARF/DWARFContext.h"
 #include "llvm/DebugInfo/Symbolize/Symbolize.h"
+#include "llvm/Demangle/Demangle.h"
 #include "llvm/MC/MCAsmInfo.h"
 #include "llvm/MC/MCContext.h"
 #include "llvm/MC/MCDisassembler/MCDisassembler.h"
@@ -90,6 +91,13 @@ static cl::alias
 DisassembleAlld("D", cl::desc("Alias for --disassemble-all"),
              cl::aliasopt(DisassembleAll));
 
+cl::opt<std::string> llvm::Demangle("demangle",
+                                    cl::desc("Demangle symbols names"),
+                                    cl::ValueOptional, cl::init("none"));
+
+static cl::alias DemangleShort("C", cl::desc("Alias for --demangle"),
+                               cl::aliasopt(Demangle));
+
 static cl::list<std::string>
 DisassembleFunctions("df",
                      cl::CommaSeparated,
@@ -330,6 +338,11 @@ LLVM_ATTRIBUTE_NORETURN void llvm::error(Twine Message) {
   exit(1);
 }
 
+void llvm::warn(StringRef Message) {
+  errs() << ToolName << ": warning: " << Message << ".\n";
+  errs().flush();
+}
+
 LLVM_ATTRIBUTE_NORETURN void llvm::report_error(StringRef File,
                                                 Twine Message) {
   errs() << ToolName << ": '" << File << "': " << Message << ".\n";
@@ -1511,7 +1524,25 @@ static void DisassembleObject(const ObjectFile *Obj, bool InlineRelocs) {
         }
       }
 
-      outs() << '\n' << std::get<1>(Symbols[si]) << ":\n";
+      auto PrintSymbol = [](StringRef Name) {
+        outs() << '\n' << Name << ":\n";
+      };
+      StringRef SymbolName = std::get<1>(Symbols[si]);
+      if (Demangle.getValue() == "" || Demangle.getValue() == "itanium") {
+        char *DemangledSymbol = nullptr;
+        size_t Size = 0;
+        int Status;
+        DemangledSymbol =
+            itaniumDemangle(SymbolName.data(), DemangledSymbol, &Size, &Status);
+        if (Status == 0)
+          PrintSymbol(StringRef(DemangledSymbol));
+        else
+          PrintSymbol(SymbolName);
+
+        if (Size != 0)
+          free(DemangledSymbol);
+      } else
+        PrintSymbol(SymbolName);
 
       // Don't print raw contents of a virtual section. A virtual section
       // doesn't have any contents in the file.
@@ -2360,6 +2391,11 @@ int main(int argc, char **argv) {
 
   if (DisassembleAll || PrintSource || PrintLines)
     Disassemble = true;
+
+  if (Demangle.getValue() != "none" && Demangle.getValue() != "" &&
+      Demangle.getValue() != "itanium")
+    warn("Unsupported demangling style");
+
   if (!Disassemble
       && !Relocations
       && !DynamicRelocations

llvm/tools/llvm-objdump/llvm-objdump.h

@@ -30,6 +30,7 @@ namespace object {
 extern cl::opt<std::string> TripleName;
 extern cl::opt<std::string> ArchName;
 extern cl::opt<std::string> MCPU;
+extern cl::opt<std::string> Demangle;
 extern cl::list<std::string> MAttrs;
 extern cl::list<std::string> FilterSections;
 extern cl::opt<bool> AllHeaders;
@@ -96,6 +97,7 @@ void PrintSectionHeaders(const object::ObjectFile *o);
 void PrintSectionContents(const object::ObjectFile *o);
 void PrintSymbolTable(const object::ObjectFile *o, StringRef ArchiveName,
                       StringRef ArchitectureName = StringRef());
+void warn(StringRef Message);
 LLVM_ATTRIBUTE_NORETURN void error(Twine Message);
 LLVM_ATTRIBUTE_NORETURN void report_error(StringRef File, Twine Message);
 LLVM_ATTRIBUTE_NORETURN void report_error(StringRef File, std::error_code EC);