[llvm] r264301 - BitcodeWriter: Split out named metadata; almost NFC

[Duncan P. N. Exon Smith via llvm-commits]

Author: dexonsmith
Date: Thu Mar 24 11:16:08 2016
New Revision: 264301

URL: http://llvm.org/viewvc/llvm-project?rev=264301&view=rev
Log:
BitcodeWriter: Split out named metadata; almost NFC

Split writeNamedMetadata out of WriteModuleMetadata to write named
metadata, and createNamedMetadataAbbrev for the abbreviation.

There should be no effective functionality change, although the layout
of the bitcode will change.  Previously, the abbreviation was emitted at
the top of the block, but now it is delayed until immediately before the
named metadata records are emitted.

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

Modified: llvm/trunk/lib/Bitcode/Writer/BitcodeWriter.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Bitcode/Writer/BitcodeWriter.cpp?rev=264301&r1=264300&r2=264301&view=diff
==============================================================================
--- llvm/trunk/lib/Bitcode/Writer/BitcodeWriter.cpp (original)
+++ llvm/trunk/lib/Bitcode/Writer/BitcodeWriter.cpp Thu Mar 24 11:16:08 2016
@@ -1301,6 +1301,36 @@ static void WriteDIImportedEntity(const
   Record.clear();
 }
 
+static unsigned createNamedMetadataAbbrev(BitstreamWriter &Stream) {
+  BitCodeAbbrev *Abbv = new BitCodeAbbrev();
+  Abbv->Add(BitCodeAbbrevOp(bitc::METADATA_NAME));
+  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
+  Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 8));
+  return Stream.EmitAbbrev(Abbv);
+}
+
+static void writeNamedMetadata(const Module &M, const ValueEnumerator &VE,
+                               BitstreamWriter &Stream,
+                               SmallVectorImpl<uint64_t> &Record) {
+  if (M.named_metadata_empty())
+    return;
+
+  unsigned Abbrev = createNamedMetadataAbbrev(Stream);
+  for (const NamedMDNode &NMD : M.named_metadata()) {
+    // Write name.
+    StringRef Str = NMD.getName();
+    Record.append(Str.bytes_begin(), Str.bytes_end());
+    Stream.EmitRecord(bitc::METADATA_NAME, Record, Abbrev);
+    Record.clear();
+
+    // Write named metadata operands.
+    for (const MDNode *N : NMD.operands())
+      Record.push_back(VE.getMetadataID(N));
+    Stream.EmitRecord(bitc::METADATA_NAMED_NODE, Record, 0);
+    Record.clear();
+  }
+}
+
 static void WriteModuleMetadata(const Module &M,
                                 const ValueEnumerator &VE,
                                 BitstreamWriter &Stream) {
@@ -1355,16 +1385,6 @@ static void WriteModuleMetadata(const Mo
     GenericDINodeAbbrev = Stream.EmitAbbrev(Abbv);
   }
 
-  unsigned NameAbbrev = 0;
-  if (!M.named_metadata_empty()) {
-    // Abbrev for METADATA_NAME.
-    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
-    Abbv->Add(BitCodeAbbrevOp(bitc::METADATA_NAME));
-    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
-    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 8));
-    NameAbbrev = Stream.EmitAbbrev(Abbv);
-  }
-
   SmallVector<uint64_t, 64> Record;
   for (const Metadata *MD : MDs) {
     if (const MDNode *N = dyn_cast<MDNode>(MD)) {
@@ -1393,21 +1413,7 @@ static void WriteModuleMetadata(const Mo
     Record.clear();
   }
 
-  // Write named metadata.
-  for (const NamedMDNode &NMD : M.named_metadata()) {
-    // Write name.
-    StringRef Str = NMD.getName();
-    Record.append(Str.bytes_begin(), Str.bytes_end());
-    Stream.EmitRecord(bitc::METADATA_NAME, Record, NameAbbrev);
-    Record.clear();
-
-    // Write named metadata operands.
-    for (const MDNode *N : NMD.operands())
-      Record.push_back(VE.getMetadataID(N));
-    Stream.EmitRecord(bitc::METADATA_NAMED_NODE, Record, 0);
-    Record.clear();
-  }
-
+  writeNamedMetadata(M, VE, Stream, Record);
   Stream.ExitBlock();
 }