Reapply "Verifier: Check for incompatible bit piece expressions"

This reverts commit r234717, reapplying r234698 (in spirit).

As described in r234717, the original `Verifier` check had a
use-after-free.  Instead of storing pointers to "interesting" debug info
intrinsics whose bit piece expressions should be verified once we have
typerefs, do a second traversal.  I've added a testcase to catch the
`llc` crasher.

Original commit message:

    Verifier: Check for incompatible bit piece expressions

    Convert an assertion into a `Verifier` check.  Bit piece expressions
    must fit inside the variable, and mustn't be the entire variable.
    Catching this in the verifier will help us find bugs sooner, and makes
    `DIVariable::getSizeInBits()` dead code.

llvm-svn: 234776

1 files changed, 0 insertions, 13 deletions

diff --git a/llvm/lib/IR/DebugInfo.cpp b/llvm/lib/IR/DebugInfo.cpp
index b0bd8223294..7797a026211 100644
--- a/llvm/lib/IR/DebugInfo.cpp
+++ b/llvm/lib/IR/DebugInfo.cpp
@@ -33,19 +33,6 @@
 using namespace llvm;
 using namespace llvm::dwarf;
 
-/// \brief Return the size reported by the variable's type.
-unsigned DIVariable::getSizeInBits(const DITypeIdentifierMap &Map) {
-  DIType Ty = getType().resolve(Map);
-  // Follow derived types until we reach a type that
-  // reports back a size.
-  while (isa<MDDerivedType>(Ty) && !Ty.getSizeInBits()) {
-    DIDerivedType DT = cast<MDDerivedType>(Ty);
-    Ty = DT.getTypeDerivedFrom().resolve(Map);
-  }
-  assert(Ty.getSizeInBits() && "type with size 0");
-  return Ty.getSizeInBits();
-}
-
 //===----------------------------------------------------------------------===//
 // Simple Descriptor Constructors and other Methods
 //===----------------------------------------------------------------------===//