Bitcode: Write the irsymtab to disk.

[pcc]

Summary

Depends on D33970

Depends on D33971

Depends on D33972

[tejohnson]

LGTM

llvm/include/llvm/Bitcode/BitcodeWriter.h

31 ↗

(On Diff #101654)

Document what this is used for.

llvm/test/Object/X86/irsymtab.ll

5 ↗

(On Diff #101654)

Can you note what offset into this dump holds the symtab version so that it is more obvious which needs to be adjusted whenever that gets bumped?

[pcc]

• Address review comments

llvm/trunk/include/llvm/Bitcode/BitcodeWriter.h

namespace llvm {
   class Module;
   class raw_ostream;
 
   class BitcodeWriter {
     SmallVectorImpl<char> &Buffer;
     std::unique_ptr<BitstreamWriter> Stream;
 
     StringTableBuilder StrtabBuilder{StringTableBuilder::RAW};
-    bool WroteStrtab = false;
+
+    // Owns any strings created by the irsymtab writer until we create the
+    // string table.
+    BumpPtrAllocator Alloc;
+
+    bool WroteStrtab = false, WroteSymtab = false;
 
     void writeBlob(unsigned Block, unsigned Record, StringRef Blob);
 
+    std::vector<Module *> Mods;
+
    public:
     /// Create a BitcodeWriter that writes to Buffer.
     BitcodeWriter(SmallVectorImpl<char> &Buffer);
 
     ~BitcodeWriter();
 
+    /// Attempt to write a symbol table to the bitcode file. This must be called
+    /// at most once after all modules have been written.
+    ///
+    /// A reader does not require a symbol table to interpret a bitcode file;
+    /// the symbol table is needed only to improve link-time performance. So
+    /// this function may decide not to write a symbol table. It may so decide
+    /// if, for example, the target is unregistered or the IR is malformed.
+    void writeSymtab();
+
     /// Write the bitcode file's string table. This must be called exactly once
-    /// after all modules have been written.
+    /// after all modules and the optional symbol table have been written.
     void writeStrtab();
 
     /// Copy the string table for another module into this bitcode file. This
     /// should be called after copying the module itself into the bitcode file.
     void copyStrtab(StringRef Strtab);
 
     /// Write the specified module to the buffer specified at construction time.
     ///

llvm/trunk/include/llvm/Bitcode/LLVMBitCodes.h

 
 #ifndef LLVM_BITCODE_LLVMBITCODES_H
 #define LLVM_BITCODE_LLVMBITCODES_H
 
 #include "llvm/Bitcode/BitCodes.h"
 
 namespace llvm {
 namespace bitc {
-// The only top-level block types are MODULE, IDENTIFICATION and STRTAB.
+// The only top-level block types are MODULE, IDENTIFICATION, STRTAB and SYMTAB.
 enum BlockIDs {
   // Blocks
   MODULE_BLOCK_ID = FIRST_APPLICATION_BLOCKID,
 
   // Module sub-block id's.
   PARAMATTR_BLOCK_ID,
   PARAMATTR_GROUP_BLOCK_ID,
 
enum BlockIDs {
 
   OPERAND_BUNDLE_TAGS_BLOCK_ID,
 
   METADATA_KIND_BLOCK_ID,
 
   STRTAB_BLOCK_ID,
 
   FULL_LTO_GLOBALVAL_SUMMARY_BLOCK_ID,
+
+  SYMTAB_BLOCK_ID,
 };
 
 /// Identification block contains a string that describes the producer details,
 /// and an epoch that defines the auto-upgrade capability.
 enum IdentificationCodes {
   IDENTIFICATION_CODE_STRING = 1, // IDENTIFICATION:      [strchr x N]
   IDENTIFICATION_CODE_EPOCH = 2,  // EPOCH:               [epoch#]
 };
enum ComdatSelectionKindCodes {
   COMDAT_SELECTION_KIND_NO_DUPLICATES = 4,
   COMDAT_SELECTION_KIND_SAME_SIZE = 5,
 };
 
 enum StrtabCodes {
   STRTAB_BLOB = 1,
 };
 
+enum SymtabCodes {
+  SYMTAB_BLOB = 1,
+};
+
 } // End bitc namespace
 } // End llvm namespace
 
 #endif

llvm/trunk/lib/Bitcode/Writer/BitcodeWriter.cpp

 #include "llvm/IR/InlineAsm.h"
 #include "llvm/IR/Instructions.h"
 #include "llvm/IR/LLVMContext.h"
 #include "llvm/IR/Module.h"
 #include "llvm/IR/Operator.h"
 #include "llvm/IR/UseListOrder.h"
 #include "llvm/IR/ValueSymbolTable.h"
 #include "llvm/MC/StringTableBuilder.h"
+#include "llvm/Object/IRSymtab.h"
 #include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/MathExtras.h"
 #include "llvm/Support/Program.h"
 #include "llvm/Support/SHA1.h"
+#include "llvm/Support/TargetRegistry.h"
 #include "llvm/Support/raw_ostream.h"
 #include <cctype>
 #include <map>
 using namespace llvm;
 
 namespace {
 
 cl::opt<unsigned>
void BitcodeWriter::writeBlob(unsigned Block, unsigned Record, StringRef Blob) {
   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
   auto AbbrevNo = Stream->EmitAbbrev(std::move(Abbv));
 
   Stream->EmitRecordWithBlob(AbbrevNo, ArrayRef<uint64_t>{Record}, Blob);
 
   Stream->ExitBlock();
 }
 
+void BitcodeWriter::writeSymtab() {
+  assert(!WroteStrtab && !WroteSymtab);
+
+  // If any module has module-level inline asm, we will require a registered asm
+  // parser for the target so that we can create an accurate symbol table for
+  // the module.
+  for (Module *M : Mods) {
+    if (M->getModuleInlineAsm().empty())
+      continue;
+
+    std::string Err;
+    const Triple TT(M->getTargetTriple());
+    const Target *T = TargetRegistry::lookupTarget(TT.str(), Err);
+    if (!T || !T->hasMCAsmParser())
+      return;
+  }
+
+  WroteSymtab = true;
+  SmallVector<char, 0> Symtab;
+  // The irsymtab::build function may be unable to create a symbol table if the
+  // module is malformed (e.g. it contains an invalid alias). Writing a symbol
+  // table is not required for correctness, but we still want to be able to
+  // write malformed modules to bitcode files, so swallow the error.
+  if (Error E = irsymtab::build(Mods, Symtab, StrtabBuilder, Alloc)) {
+    consumeError(std::move(E));
+    return;
+  }
+
+  writeBlob(bitc::SYMTAB_BLOCK_ID, bitc::SYMTAB_BLOB,
+            {Symtab.data(), Symtab.size()});
+}
+
 void BitcodeWriter::writeStrtab() {
   assert(!WroteStrtab);
 
   std::vector<char> Strtab;
   StrtabBuilder.finalizeInOrder();
   Strtab.resize(StrtabBuilder.getSize());
   StrtabBuilder.write((uint8_t *)Strtab.data());
 
   writeBlob(bitc::STRTAB_BLOCK_ID, bitc::STRTAB_BLOB,
             {Strtab.data(), Strtab.size()});
 
   WroteStrtab = true;
 }
 
 void BitcodeWriter::copyStrtab(StringRef Strtab) {
   writeBlob(bitc::STRTAB_BLOCK_ID, bitc::STRTAB_BLOB, Strtab);
   WroteStrtab = true;
 }
 
 void BitcodeWriter::writeModule(const Module *M,
                                 bool ShouldPreserveUseListOrder,
                                 const ModuleSummaryIndex *Index,
                                 bool GenerateHash, ModuleHash *ModHash) {
+  assert(!WroteStrtab);
+
+  // The Mods vector is used by irsymtab::build, which requires non-const
+  // Modules in case it needs to materialize metadata. But the bitcode writer
+  // requires that the module is materialized, so we can cast to non-const here,
+  // after checking that it is in fact materialized.
+  assert(M->isMaterialized());
+  Mods.push_back(const_cast<Module *>(M));
+
   ModuleBitcodeWriter ModuleWriter(M, Buffer, StrtabBuilder, *Stream,
                                    ShouldPreserveUseListOrder, Index,
                                    GenerateHash, ModHash);
   ModuleWriter.write();
 }
 
 void BitcodeWriter::writeIndex(
     const ModuleSummaryIndex *Index,
void llvm::WriteBitcodeToFile(const Module *M, raw_ostream &Out,
   // header.
   Triple TT(M->getTargetTriple());
   if (TT.isOSDarwin() || TT.isOSBinFormatMachO())
     Buffer.insert(Buffer.begin(), BWH_HeaderSize, 0);
 
   BitcodeWriter Writer(Buffer);
   Writer.writeModule(M, ShouldPreserveUseListOrder, Index, GenerateHash,
                      ModHash);
+  Writer.writeSymtab();
   Writer.writeStrtab();
 
   if (TT.isOSDarwin() || TT.isOSBinFormatMachO())
     emitDarwinBCHeaderAndTrailer(Buffer, TT);
 
   // Write the generated bitstream to "Out".
   Out.write((char*)&Buffer.front(), Buffer.size());
 }

llvm/trunk/lib/Object/CMakeLists.txt

add_llvm_library(LLVMObject
   WasmObjectFile.cpp
   WindowsResource.cpp
 
   ADDITIONAL_HEADER_DIRS
   ${LLVM_MAIN_INCLUDE_DIR}/llvm/Object
 
   DEPENDS
   intrinsics_gen
+  llvm_vcsrevision_h
   )

llvm/trunk/lib/Transforms/IPO/ThinLTOBitcodeWriter.cpp

void splitAndWriteThinLTOBitcode(
   // Save the module hash produced for the full bitcode, which will
   // be used in the backends, and use that in the minimized bitcode
   // produced for the full link.
   ModuleHash ModHash = {{0}};
   W.writeModule(&M, /*ShouldPreserveUseListOrder=*/false, &Index,
                 /*GenerateHash=*/true, &ModHash);
   W.writeModule(MergedM.get(), /*ShouldPreserveUseListOrder=*/false,
                 &MergedMIndex);
+  W.writeSymtab();
   W.writeStrtab();
   OS << Buffer;
 
   // If a minimized bitcode module was requested for the thin link,
   // strip the debug info (the merged module was already stripped above)
   // and write it to the given OS.
   if (ThinLinkOS) {
     Buffer.clear();
     BitcodeWriter W2(Buffer);
     StripDebugInfo(M);
     W2.writeModule(&M, /*ShouldPreserveUseListOrder=*/false, &Index,
                    /*GenerateHash=*/false, &ModHash);
     W2.writeModule(MergedM.get(), /*ShouldPreserveUseListOrder=*/false,
                    &MergedMIndex);
+    W2.writeSymtab();
     W2.writeStrtab();
     *ThinLinkOS << Buffer;
   }
 }
 
 // Returns whether this module needs to be split because it uses type metadata.
 bool requiresSplit(Module &M) {
   SmallVector<MDNode *, 1> MDs;

llvm/trunk/test/Bitcode/thinlto-alias.ll

 ; CHECK:       <GLOBALVAL_SUMMARY_BLOCK
 ; CHECK-NEXT:    <VERSION
 ; See if the call to func is registered.
 ; The value id 1 matches the second FUNCTION record above.
 ; CHECK-NEXT:    <PERMODULE {{.*}} op4=1/>
 ; CHECK-NEXT:  </GLOBALVAL_SUMMARY_BLOCK>
 
 ; CHECK: <STRTAB_BLOCK
-; CHECK-NEXT: blob data = 'mainanalias'
+; CHECK-NEXT: blob data = 'mainanalias{{.*}}'
 
 ; COMBINED:       <GLOBALVAL_SUMMARY_BLOCK
 ; COMBINED-NEXT:    <VERSION
 ; See if the call to analias is registered, using the expected value id.
 ; COMBINED-NEXT:    <VALUE_GUID op0=[[ALIASID:[0-9]+]] op1=-5751648690987223394/>
 ; COMBINED-NEXT:    <VALUE_GUID
 ; COMBINED-NEXT:    <VALUE_GUID op0=[[ALIASEEID:[0-9]+]] op1=-1039159065113703048/>
 ; COMBINED-NEXT:    <COMBINED {{.*}} op5=[[ALIASID]]/>

llvm/trunk/test/Bitcode/thinlto-function-summary-callgraph-pgo.ll

 ; "func"
 ; CHECK-NEXT: <FUNCTION op0=4 op1=4
 ; CHECK:       <GLOBALVAL_SUMMARY_BLOCK
 ; CHECK-NEXT:    <VERSION
 ; See if the call to func is registered, using the expected hotness type.
 ; CHECK-NEXT:    <PERMODULE_PROFILE {{.*}} op4=1 op5=2/>
 ; CHECK-NEXT:  </GLOBALVAL_SUMMARY_BLOCK>
 ; CHECK: <STRTAB_BLOCK
-; CHECK-NEXT: blob data = 'mainfunc'
+; CHECK-NEXT: blob data = 'mainfunc{{.*}}'
 
 ; COMBINED:       <GLOBALVAL_SUMMARY_BLOCK
 ; COMBINED-NEXT:    <VERSION
 ; COMBINED-NEXT:    <VALUE_GUID op0=[[FUNCID:[0-9]+]] op1=7289175272376759421/>
 ; COMBINED-NEXT:    <VALUE_GUID
 ; COMBINED-NEXT:    <COMBINED
 ; See if the call to func is registered, using the expected hotness type.
 ; op6=2 which is hotnessType::None.

llvm/trunk/test/Bitcode/thinlto-function-summary-callgraph-profile-summary.ll

 ; CHECK-LABEL:       <GLOBALVAL_SUMMARY_BLOCK
 ; CHECK-NEXT:    <VERSION
 ; CHECK-NEXT:    <VALUE_GUID op0=25 op1=123/>
 ; op4=hot1 op6=cold op8=hot2 op10=hot4 op12=none1 op14=hot3 op16=none2 op18=none3 op20=123
 ; CHECK-NEXT:    <PERMODULE_PROFILE {{.*}} op4=1 op5=3 op6=5 op7=1 op8=2 op9=3 op10=4 op11=1 op12=6 op13=2 op14=3 op15=3 op16=7 op17=2 op18=8 op19=2 op20=25 op21=3/>
 ; CHECK-NEXT:  </GLOBALVAL_SUMMARY_BLOCK>
 
 ; CHECK: <STRTAB_BLOCK
-; CHECK-NEXT: blob data = 'hot_functionhot1hot2hot3hot4coldnone1none2none3'
+; CHECK-NEXT: blob data = 'hot_functionhot1hot2hot3hot4coldnone1none2none3{{.*}}'
 
 ; COMBINED:       <GLOBALVAL_SUMMARY_BLOCK
 ; COMBINED-NEXT:    <VERSION
 ; COMBINED-NEXT:    <VALUE_GUID
 ; COMBINED-NEXT:    <VALUE_GUID
 ; COMBINED-NEXT:    <VALUE_GUID
 ; COMBINED-NEXT:    <VALUE_GUID
 ; COMBINED-NEXT:    <VALUE_GUID

llvm/trunk/test/Bitcode/thinlto-function-summary-callgraph-sample-profile-summary.ll

 ; CHECK-LABEL:       <GLOBALVAL_SUMMARY_BLOCK
 ; CHECK-NEXT:    <VERSION
 ; CHECK-NEXT:    <VALUE_GUID op0=25 op1=123/>
 ; op4=hot1 op6=cold op8=hot2 op10=hot4 op12=none1 op14=hot3 op16=none2 op18=none3 op20=123
 ; CHECK-NEXT:    <PERMODULE_PROFILE {{.*}} op4=1 op5=3 op6=5 op7=1 op8=2 op9=3 op10=4 op11=3 op12=6 op13=2 op14=3 op15=3 op16=7 op17=2 op18=8 op19=2 op20=25 op21=3/>
 ; CHECK-NEXT:  </GLOBALVAL_SUMMARY_BLOCK>
 
 ; CHECK: <STRTAB_BLOCK
-; CHECK-NEXT: blob data = 'hot_functionhot1hot2hot3hot4coldnone1none2none3'
+; CHECK-NEXT: blob data = 'hot_functionhot1hot2hot3hot4coldnone1none2none3{{.*}}'
 
 ; COMBINED:       <GLOBALVAL_SUMMARY_BLOCK
 ; COMBINED-NEXT:    <VERSION
 ; COMBINED-NEXT:    <VALUE_GUID
 ; COMBINED-NEXT:    <VALUE_GUID
 ; COMBINED-NEXT:    <VALUE_GUID
 ; COMBINED-NEXT:    <VALUE_GUID
 ; COMBINED-NEXT:    <VALUE_GUID

llvm/trunk/test/Bitcode/thinlto-function-summary-callgraph.ll

 ; "func"
 ; CHECK-NEXT: <FUNCTION op0=17 op1=4
 ; CHECK:       <GLOBALVAL_SUMMARY_BLOCK
 ; CHECK-NEXT:    <VERSION
 ; See if the call to func is registered.
 ; CHECK-NEXT:    <PERMODULE {{.*}} op3=1
 ; CHECK-NEXT:  </GLOBALVAL_SUMMARY_BLOCK>
 ; CHECK: <STRTAB_BLOCK
-; CHECK-NEXT: blob data = 'undefinedglobmainfunc'
+; CHECK-NEXT: blob data = 'undefinedglobmainfunc{{.*}}'
 
 
 ; COMBINED:       <GLOBALVAL_SUMMARY_BLOCK
 ; COMBINED-NEXT:    <VERSION
 ; Only 2 VALUE_GUID since reference to undefinedglob should not be included in
 ; combined index.
 ; COMBINED-NEXT:    <VALUE_GUID op0=[[FUNCID:[0-9]+]] op1=7289175272376759421/>
 ; COMBINED-NEXT:    <VALUE_GUID

llvm/trunk/test/Bitcode/thinlto-function-summary-refgraph.ll

 ; op0=Z op4=func2
 ; CHECK-DAG:    <PERMODULE {{.*}} op0=9 op1=3 {{.*}} op3=0 op4=3/>
 ; Variable bar initialization contains address reference to func:
 ; op0=bar op2=func
 ; CHECK-DAG:    <PERMODULE_GLOBALVAR_INIT_REFS {{.*}} op0=0 op1=0 op2=2/>
 ; CHECK:  </GLOBALVAL_SUMMARY_BLOCK>
 
 ; CHECK: <STRTAB_BLOCK
-; CHECK-NEXT: blob data = 'barglobalvarfuncfunc2foofunc3WXYZllvm.ctpop.i8main'
+; CHECK-NEXT: blob data = 'barglobalvarfuncfunc2foofunc3WXYZllvm.ctpop.i8main{{.*}}'
 
 ; ModuleID = 'thinlto-function-summary-refgraph.ll'
 target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
 target triple = "x86_64-unknown-linux-gnu"
 
 @bar = global void (...)* bitcast (void ()* @func to void (...)*), align 8
 
 @globalvar = global i32 0, align 4

llvm/trunk/test/Bitcode/thinlto-function-summary.ll

 ; BC-NEXT: <VERSION
 ; BC-NEXT: <PERMODULE {{.*}} op0=1 op1=0
 ; BC-NEXT: <PERMODULE {{.*}} op0=2 op1=0
 ; BC-NEXT: <PERMODULE {{.*}} op0=3 op1=7
 ; BC-NEXT: <PERMODULE {{.*}} op0=4 op1=16
 ; BC-NEXT: <ALIAS {{.*}} op0=5 op1=0 op2=3
 ; BC-NEXT: </GLOBALVAL_SUMMARY_BLOCK
 ; BC: <STRTAB_BLOCK
-; BC-NEXT: blob data = 'hfoobaranon.{{................................}}.0variadicf'
+; BC-NEXT: blob data = 'hfoobaranon.{{................................}}.0variadicf{{.*}}'
 
 
 ; RUN: opt -name-anon-globals -module-summary < %s | llvm-dis | FileCheck %s
 ; Check that this round-trips correctly.
 
 ; ModuleID = '<stdin>'
 target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
 target triple = "x86_64-unknown-linux-gnu"

llvm/trunk/test/Object/X86/irsymtab-asm.ll

+; Check that we correctly handle the case where we have inline asm and the
+; target is not registered. In this case we shouldn't emit an irsymtab.
+
+; RUN: llvm-as -o %t %s
+; RUN: llvm-bcanalyzer -dump %t | FileCheck --check-prefix=AS %s
+
+; AS-NOT: <SYMTAB_BLOCK
+
+; RUN: opt -o %t2 %s
+; RUN: llvm-bcanalyzer -dump %t2 | FileCheck --check-prefix=OPT %s
+
+; OPT: <SYMTAB_BLOCK
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+module asm "ret"

llvm/trunk/test/Object/X86/irsymtab-bad-alias.ll

+; Check that we do not create an irsymtab for modules with malformed IR.
+
+; RUN: opt -o %t %s
+; RUN: llvm-bcanalyzer -dump %t | FileCheck %s
+
+; CHECK-NOT: <SYMTAB_BLOCK
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+@g1 = global i32 1
+@g2 = global i32 2
+
+@a = alias i32, inttoptr(i32 sub (i32 ptrtoint (i32* @g1 to i32),
+                                  i32 ptrtoint (i32* @g2 to i32)) to i32*)

llvm/trunk/test/Object/X86/irsymtab.ll

+; RUN: env LLVM_OVERRIDE_PRODUCER=producer opt -o %t %s
+; RUN: llvm-bcanalyzer -dump -show-binary-blobs %t | FileCheck --check-prefix=BCA %s
+
+; BCA:      <SYMTAB_BLOCK
+; Version stored at offset 0.
+; BCA-NEXT:   <BLOB abbrevid=4/> blob data = '\x00\x00\x00\x00\x06\x00\x00\x00\x08\x00\x00\x00D\x00\x00\x00\x01\x00\x00\x00P\x00\x00\x00\x00\x00\x00\x00P\x00\x00\x00\x02\x00\x00\x00\x80\x00\x00\x00\x00\x00\x00\x00\x0E\x00\x00\x00\x18\x00\x00\x00&\x00\x00\x00\x0B\x00\x00\x001\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x03\x00\x00\x00\x00\x00\x00\x00\x03\x00\x00\x00\xFF\xFF\xFF\xFF\x00$\x00\x00\x03\x00\x00\x00\x03\x00\x00\x00\x03\x00\x00\x00\x03\x00\x00\x00\xFF\xFF\xFF\xFF\x08$\x00\x00'
+; BCA-NEXT: </SYMTAB_BLOCK>
+; BCA-NEXT: <STRTAB_BLOCK
+; BCA-NEXT:   <BLOB abbrevid=4/> blob data = 'foobarproducerx86_64-unknown-linux-gnuirsymtab.ll'
+; BCA-NEXT: </STRTAB_BLOCK>
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+source_filename = "irsymtab.ll"
+
+define void @foo() {
+  ret void
+}
+
+declare void @bar()

llvm/trunk/test/ThinLTO/X86/autoupgrade.ll

 ; Verify that auto-upgrading intrinsics works with Lazy loaded bitcode
 ; Do setup work for all below tests: generate bitcode and combined index
 ; RUN: opt -module-summary %s -o %t.bc
 ; RUN: llvm-lto -thinlto-action=thinlink -o %t3.bc %t.bc %p/Inputs/autoupgrade.bc
 
 ; We can't use llvm-dis here, because it would do the autoupgrade itself.
 
 ; RUN: llvm-link  -summary-index=%t3.bc \
 ; RUN:            -import=globalfunc1:%p/Inputs/autoupgrade.bc %t.bc \
 ; RUN:     | llvm-bcanalyzer -dump | FileCheck %s
 
 ; CHECK: <STRTAB_BLOCK
-; CHECK-NEXT: blob data = 'mainglobalfunc1llvm.invariant.start.p0i8'
+; CHECK-NEXT: blob data = 'mainglobalfunc1llvm.invariant.start.p0i8{{.*}}'
 
 target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
 target triple = "x86_64-apple-macosx10.11.0"
 
 define i32 @main() #0 {
 entry:
   call void (...) @globalfunc1()
   ret i32 0
 }
 
 declare void @globalfunc1(...) #1

llvm/trunk/tools/llvm-bcanalyzer/llvm-bcanalyzer.cpp

static const char *GetBlockName(unsigned BlockID,
   case bitc::METADATA_ATTACHMENT_ID:       return "METADATA_ATTACHMENT_BLOCK";
   case bitc::USELIST_BLOCK_ID:             return "USELIST_BLOCK_ID";
   case bitc::GLOBALVAL_SUMMARY_BLOCK_ID:
                                            return "GLOBALVAL_SUMMARY_BLOCK";
   case bitc::FULL_LTO_GLOBALVAL_SUMMARY_BLOCK_ID:
                                       return "FULL_LTO_GLOBALVAL_SUMMARY_BLOCK";
   case bitc::MODULE_STRTAB_BLOCK_ID:       return "MODULE_STRTAB_BLOCK";
   case bitc::STRTAB_BLOCK_ID:              return "STRTAB_BLOCK";
+  case bitc::SYMTAB_BLOCK_ID:              return "SYMTAB_BLOCK";
   }
 }
 
 /// GetCodeName - Return a symbolic code name if known, otherwise return
 /// null.
 static const char *GetCodeName(unsigned CodeID, unsigned BlockID,
                                const BitstreamBlockInfo &BlockInfo,
                                CurStreamTypeType CurStreamType) {
case bitc::OPERAND_BUNDLE_TAGS_BLOCK_ID:
     default: return nullptr;
     case bitc::OPERAND_BUNDLE_TAG: return "OPERAND_BUNDLE_TAG";
     }
   case bitc::STRTAB_BLOCK_ID:
     switch(CodeID) {
     default: return nullptr;
     case bitc::STRTAB_BLOB: return "BLOB";
     }
+  case bitc::SYMTAB_BLOCK_ID:
+    switch(CodeID) {
+    default: return nullptr;
+    case bitc::SYMTAB_BLOB: return "BLOB";
+    }
   }
 #undef STRINGIFY_CODE
 }
 
 struct PerRecordStats {
   unsigned NumInstances;
   unsigned NumAbbrev;
   uint64_t TotalBits;