[DebugInfo][COFF] Fix reading variable-length encoded records

While reading Codeview records which contain variable-length encoded integers,
such as LF_BCLASS, LF_ENUMERATE, LF_MEMBER, LF_VBCLASS or LF_IVBCLASS,
the record's size would be improperly calculated in cases where the value was
indeed of a variable length (>= LF_NUMERIC). This caused a bad alignement on
the next record, which would/might crash later on.

Differential Revision: https://reviews.llvm.org/D45104

llvm-svn: 329659

1 files changed, 8 insertions, 0 deletions

diff --git a/llvm/unittests/DebugInfo/CodeView/TypeIndexDiscoveryTest.cpp b/llvm/unittests/DebugInfo/CodeView/TypeIndexDiscoveryTest.cpp
index 14d358dd152..54da2b719e9 100644
--- a/llvm/unittests/DebugInfo/CodeView/TypeIndexDiscoveryTest.cpp
+++ b/llvm/unittests/DebugInfo/CodeView/TypeIndexDiscoveryTest.cpp
@@ -593,3 +593,11 @@ TEST_F(TypeIndexIteratorTest, Precomp) {
   writeTypeRecords(P, EP);
   checkTypeReferences(0);
 }
+
+// This is a test for getEncodedIntegerLength()
+TEST_F(TypeIndexIteratorTest, VariableSizeIntegers) {
+  BaseClassRecord BaseClass1(MemberAccess::Public, TypeIndex(47), (uint64_t)-1);
+  BaseClassRecord BaseClass2(MemberAccess::Public, TypeIndex(48), 1);
+  writeFieldList(BaseClass1, BaseClass2);
+  checkTypeReferences(0, TypeIndex(47), TypeIndex(48));
+}
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