From 5be5607a0fa62a5eca4fc9db3ce112e66cd76cfb Mon Sep 17 00:00:00 2001
From: Jordan Rose <jordan_rose@apple.com>
Date: Thu, 9 May 2013 00:19:10 +0000
Subject: [PATCH] [serialization] Write a BLOCKINFO block so llvm-bcanalyzer is
 useful.

This adds names to the other blocks and records in the file.

The tests now require llvm-bcanalyzer to run; please build that along
with 'FileCheck' and 'not'.

Swift SVN r5109
---
 lib/Serialization/Serialization.cpp | 55 ++++++++++++++++++++++++++---
 test/Serialization/empty.swift      | 24 +++++++++++++
 test/Serialization/test.swift       |  3 --
 3 files changed, 75 insertions(+), 7 deletions(-)
 create mode 100644 test/Serialization/empty.swift
 delete mode 100644 test/Serialization/test.swift

diff --git a/lib/Serialization/Serialization.cpp b/lib/Serialization/Serialization.cpp
index fe3a823eb24..8ec4bff5c41 100644
--- a/lib/Serialization/Serialization.cpp
+++ b/lib/Serialization/Serialization.cpp
@@ -35,7 +35,11 @@ namespace {
     /// A reusable buffer for emitting records.
     SmallVector<uint64_t, 64> ScratchRecord;
 
-    /// Writes the Swift module file header and BLOCKINFO block.
+    /// Writes the BLOCKINFO block.
+    void writeBlockInfoBlock();
+
+    /// Writes the Swift module file header, BLOCKINFO block, and
+    /// non-TU-specific metadata.
     void writeHeader();
 
     /// Writes the input file paths.
@@ -53,6 +57,51 @@ namespace {
   };
 } // end anonymous namespace
 
+
+/// Record the name of a block.
+static void emitBlockID(llvm::BitstreamWriter &out, unsigned ID,
+                        StringRef name,
+                        SmallVectorImpl<unsigned char> &nameBuffer) {
+  SmallVector<unsigned, 1> idBuffer;
+  idBuffer.push_back(ID);
+  out.EmitRecord(llvm::bitc::BLOCKINFO_CODE_SETBID, idBuffer);
+
+  // Emit the block name if present.
+  if (name.empty())
+    return;
+  nameBuffer.resize(name.size());
+  memcpy(nameBuffer.data(), name.data(), name.size());
+  out.EmitRecord(llvm::bitc::BLOCKINFO_CODE_BLOCKNAME, nameBuffer);
+}
+
+/// Record the name of a record within a block.
+static void emitRecordID(llvm::BitstreamWriter &out, unsigned ID,
+                         StringRef name,
+                         SmallVectorImpl<unsigned char> &nameBuffer) {
+  assert(ID < 256 && "can't fit record ID in next to name");
+  nameBuffer.resize(name.size()+1);
+  nameBuffer[0] = ID;
+  memcpy(nameBuffer.data()+1, name.data(), name.size());
+  out.EmitRecord(llvm::bitc::BLOCKINFO_CODE_SETRECORDNAME, nameBuffer);
+}
+
+void Serializer::writeBlockInfoBlock() {
+  BCBlockRAII restoreBlock(Out, llvm::bitc::BLOCKINFO_BLOCK_ID, 2);
+
+  SmallVector<unsigned char, 64> nameBuffer;
+#define BLOCK(X) emitBlockID(Out, X ## _ID, #X, nameBuffer)
+#define RECORD(X) emitRecordID(Out, X, #X, nameBuffer)
+
+  BLOCK(CONTROL_BLOCK);
+  RECORD(METADATA);
+
+  BLOCK(INPUT_BLOCK);
+  RECORD(SOURCE_FILE);
+
+#undef BLOCK
+#undef RECORD
+}
+
 void Serializer::writeHeader() {
   // Swift module file type: 'SMod'.
   Out.Emit((unsigned)'S', 8);
@@ -60,9 +109,7 @@ void Serializer::writeHeader() {
   Out.Emit((unsigned)'o', 8);
   Out.Emit((unsigned)'d', 8);
 
-  {
-    BCBlockRAII restoreBlock(Out, llvm::bitc::BLOCKINFO_BLOCK_ID, 2);
-  }
+  writeBlockInfoBlock();
 
   {
     BCBlockRAII restoreBlock(Out, CONTROL_BLOCK_ID, 3);
diff --git a/test/Serialization/empty.swift b/test/Serialization/empty.swift
new file mode 100644
index 00000000000..23cee15224a
--- /dev/null
+++ b/test/Serialization/empty.swift
@@ -0,0 +1,24 @@
+// RUN: %swift -emit-module -o %t.sm %s
+// RUN: llvm-bcanalyzer %t.sm | FileCheck %s
+
+
+// CHECK:  Block ID #0 (BLOCKINFO_BLOCK):
+// CHECK-NEXT:      Num Instances: 1
+
+// CHECK:  Block ID #8 (CONTROL_BLOCK):
+// CHECK-NEXT:      Num Instances: 1
+// CHECK-NEXT:         Total Size:
+// CHECK-NEXT:    Percent of file:
+// CHECK-NEXT:      Num SubBlocks: 0
+// CHECK-NEXT:        Num Abbrevs: 1
+// CHECK-NEXT:        Num Records: 1
+// CHECK-NEXT:    Percent Abbrevs: 100.0000%
+
+// CHECK:  Block ID #9 (INPUT_BLOCK):
+// CHECK-NEXT:      Num Instances: 1
+// CHECK-NEXT:         Total Size:
+// CHECK-NEXT:    Percent of file:
+// CHECK-NEXT:      Num SubBlocks: 0
+// CHECK-NEXT:        Num Abbrevs: 1
+// CHECK-NEXT:        Num Records: 1
+// CHECK-NEXT:    Percent Abbrevs: 100.0000%
diff --git a/test/Serialization/test.swift b/test/Serialization/test.swift
deleted file mode 100644
index 6572f3e7aaf..00000000000
--- a/test/Serialization/test.swift
+++ /dev/null
@@ -1,3 +0,0 @@
-// RUN: %swift -emit-module -o %t.sm %s
-
-// Just don't crash.