Use a different block id for block of metadata kind records

Summary:
There are currently two blocks with the METADATA_BLOCK id at module
scope. The first has the module-level metadata values (consisting of
some combination of METADATA_* record codes except for METADATA_KIND).
The second consists only of METADATA_KIND records. The latter is used
only in the METADATA_ATTACHMENT block within function blocks (for
metadata attached to instructions).

For ThinLTO we want to delay the parsing of module level metadata
until all functions have been imported from that module (there is some
bookkeeping used to suture it up when we read it during a post-pass).
However, we do need the METADATA_KIND records when parsing the function
body during importing, since those kinds are used as described above.

To simplify identification and parsing of just the block containing
the metadata kinds, use a different block id (METADATA_KIND_BLOCK_ID).
Support older bitcode without the new block id as well.

Reviewers: dexonsmith, joker.eph

Subscribers: davidxl, llvm-commits

Differential Revision: http://reviews.llvm.org/D14654

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@253154 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 8 insertions, 1 deletions

diff --git a/tools/llvm-bcanalyzer/llvm-bcanalyzer.cpp b/tools/llvm-bcanalyzer/llvm-bcanalyzer.cpp
index 3c82779ab1ea..c460eb534cda 100644
--- a/tools/llvm-bcanalyzer/llvm-bcanalyzer.cpp
+++ b/tools/llvm-bcanalyzer/llvm-bcanalyzer.cpp
@@ -114,6 +114,7 @@ static const char *GetBlockName(unsigned BlockID,
     return "IDENTIFICATION_BLOCK_ID";
   case bitc::VALUE_SYMTAB_BLOCK_ID:    return "VALUE_SYMTAB";
   case bitc::METADATA_BLOCK_ID:        return "METADATA_BLOCK";
+  case bitc::METADATA_KIND_BLOCK_ID:   return "METADATA_KIND_BLOCK";
   case bitc::METADATA_ATTACHMENT_ID:   return "METADATA_ATTACHMENT_BLOCK";
   case bitc::USELIST_BLOCK_ID:         return "USELIST_BLOCK_ID";
   case bitc::FUNCTION_SUMMARY_BLOCK_ID:
@@ -305,7 +306,7 @@ static const char *GetCodeName(unsigned CodeID, unsigned BlockID,
     default:return nullptr;
       STRINGIFY_CODE(METADATA, STRING)
       STRINGIFY_CODE(METADATA, NAME)
-      STRINGIFY_CODE(METADATA, KIND)
+      STRINGIFY_CODE(METADATA, KIND) // Older bitcode has it in a MODULE_BLOCK
       STRINGIFY_CODE(METADATA, NODE)
       STRINGIFY_CODE(METADATA, VALUE)
       STRINGIFY_CODE(METADATA, OLD_NODE)
@@ -335,6 +336,12 @@ static const char *GetCodeName(unsigned CodeID, unsigned BlockID,
       STRINGIFY_CODE(METADATA, IMPORTED_ENTITY)
       STRINGIFY_CODE(METADATA, MODULE)
     }
+  case bitc::METADATA_KIND_BLOCK_ID:
+    switch (CodeID) {
+    default:
+      return nullptr;
+      STRINGIFY_CODE(METADATA, KIND)
+    }
   case bitc::USELIST_BLOCK_ID:
     switch(CodeID) {
     default:return nullptr;