commit 16c7bdaf3245d23b9b441144f5efb610e2044927
author Scott Linder <scott@scottlinder.com> Fri Feb 23 23:01:06 2018 +0000
committer Scott Linder <scott@scottlinder.com> Fri Feb 23 23:01:06 2018 +0000
tree 870f3b5c5c606b19951cb4433f3887825bc61e56
parent 5e2f6ba51e89c9b9625902f0c36493ad46e46a3b

[DebugInfo] Support DWARF v5 source code embedding extension

In DWARF v5 the Line Number Program Header is extensible, allowing values with
new content types. In this extension a content type is added,
DW_LNCT_LLVM_source, which contains the embedded source code of the file.

Add new optional attribute for !DIFile IR metadata called source which contains
source text. Use this to output the source to the DWARF line table of code
objects. Analogously extend METADATA_FILE in Bitcode and .file directive in ASM
to support optional source.

Teach llvm-dwarfdump and llvm-objdump about the new values. Update the output
format of llvm-dwarfdump to make room for the new attribute on file_names
entries, and support embedded sources for the -source option in llvm-objdump.

Differential Revision: https://reviews.llvm.org/D42765

llvm-svn: 325970

llvm/lib/Bitcode/Reader/MetadataLoader.cpp

diff --git a/llvm/lib/Bitcode/Reader/MetadataLoader.cpp b/llvm/lib/Bitcode/Reader/MetadataLoader.cpp
index 0931192..efaee21 100644
--- a/llvm/lib/Bitcode/Reader/MetadataLoader.cpp
+++ b/llvm/lib/Bitcode/Reader/MetadataLoader.cpp
@@ -1350,7 +1350,7 @@
   }
 
   case bitc::METADATA_FILE: {
-    if (Record.size() != 3 && Record.size() != 5)
+    if (Record.size() != 3 && Record.size() != 5 && Record.size() != 6)
       return error("Invalid record");
 
     IsDistinct = Record[0];
@@ -1360,14 +1360,15 @@
     // and the old encoding for CSK_None in the ChecksumKind. The new
     // representation reserves the value 0 in the ChecksumKind to continue to
     // encode None in a backwards-compatible way.
-    if (Record.size() == 5 && Record[3] && Record[4])
+    if (Record.size() > 4 && Record[3] && Record[4])
       Checksum.emplace(static_cast<DIFile::ChecksumKind>(Record[3]),
                        getMDString(Record[4]));
     MetadataList.assignValue(
         GET_OR_DISTINCT(
             DIFile,
-            (Context, getMDString(Record[1]), getMDString(Record[2]),
-             Checksum)),
+            (Context, getMDString(Record[1]), getMDString(Record[2]), Checksum,
+             Record.size() > 5 ? Optional<MDString *>(getMDString(Record[5]))
+                               : None)),
         NextMetadataNo);
     NextMetadataNo++;
     break;

llvm/lib/Bitcode/Writer/BitcodeWriter.cpp

diff --git a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
index 832f494..0738b90 100644
--- a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
+++ b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
@@ -1560,6 +1560,9 @@
     Record.push_back(0);
     Record.push_back(VE.getMetadataOrNullID(nullptr));
   }
+  auto Source = N->getRawSource();
+  if (Source)
+    Record.push_back(VE.getMetadataOrNullID(*Source));
 
   Stream.EmitRecord(bitc::METADATA_FILE, Record, Abbrev);
   Record.clear();