AsmParser/Bitcode: Add support for MDLocation

This adds assembly and bitcode support for `MDLocation`.  The assembly
side is rather big, since this is the first `MDNode` subclass (that
isn't `MDTuple`).  Part of PR21433.

(If you're wondering where the mountains of testcase updates are, we
don't need them until I update `DILocation` and `DebugLoc` to actually
use this class.)

llvm-svn: 225830

1 files changed, 14 insertions, 0 deletions

diff --git a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
index 6f58f2241a6..60a380d5d26 100644
--- a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
+++ b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
@@ -1267,6 +1267,20 @@ std::error_code BitcodeReader::ParseMetadata() {
                               NextMDValueNo++);
       break;
     }
+    case bitc::METADATA_LOCATION: {
+      if (Record.size() != 5)
+        return Error("Invalid record");
+
+      auto get = Record[0] ? MDLocation::getDistinct : MDLocation::get;
+      unsigned Line = Record[1];
+      unsigned Column = Record[2];
+      MDNode *Scope = cast<MDNode>(MDValueList.getValueFwdRef(Record[3]));
+      Metadata *InlinedAt =
+          Record[4] ? MDValueList.getValueFwdRef(Record[4] - 1) : nullptr;
+      MDValueList.AssignValue(get(Context, Line, Column, Scope, InlinedAt),
+                              NextMDValueNo++);
+      break;
+    }
     case bitc::METADATA_STRING: {
       std::string String(Record.begin(), Record.end());
       llvm::UpgradeMDStringConstant(String);