Bitcode: Correctly handle Fixed and VBR arrays in BitstreamCursor::skipRecord().

The assertions were wrong; we need to call getEncodingData() on the element,
not the array. While here, simplify the skipRecord() implementation for Fixed
and Char6 arrays. This is tested by the code I added to llvm-bcanalyzer
which makes sure that we can skip any record.

Differential Revision: https://reviews.llvm.org/D27241

llvm-svn: 288315

1 files changed, 4 insertions, 6 deletions

diff --git a/llvm/lib/Bitcode/Reader/BitstreamReader.cpp b/llvm/lib/Bitcode/Reader/BitstreamReader.cpp
index f1237069f7b..43c9aebd79e 100644
--- a/llvm/lib/Bitcode/Reader/BitstreamReader.cpp
+++ b/llvm/lib/Bitcode/Reader/BitstreamReader.cpp
@@ -131,18 +131,16 @@ void BitstreamCursor::skipRecord(unsigned AbbrevID) {
       default:
         report_fatal_error("Array element type can't be an Array or a Blob");
       case BitCodeAbbrevOp::Fixed:
-        assert((unsigned)Op.getEncodingData() <= MaxChunkSize);
-        for (; NumElts; --NumElts)
-          Read((unsigned)EltEnc.getEncodingData());
+        assert((unsigned)EltEnc.getEncodingData() <= MaxChunkSize);
+        JumpToBit(GetCurrentBitNo() + NumElts * EltEnc.getEncodingData());
         break;
       case BitCodeAbbrevOp::VBR:
-        assert((unsigned)Op.getEncodingData() <= MaxChunkSize);
+        assert((unsigned)EltEnc.getEncodingData() <= MaxChunkSize);
         for (; NumElts; --NumElts)
           ReadVBR64((unsigned)EltEnc.getEncodingData());
         break;
       case BitCodeAbbrevOp::Char6:
-        for (; NumElts; --NumElts)
-          Read(6);
+        JumpToBit(GetCurrentBitNo() + NumElts * 6);
         break;
       }
       continue;