[opaque pointer types] Use the pointee type loaded from bitcode when constructing a LoadInst

Now (with a few carefully placed suppressions relating to general type
serialization, etc) we can round trip a simple load through bitcode and
textual IR without calling getElementType on a PointerType.

llvm-svn: 235221

1 files changed, 6 insertions, 5 deletions

diff --git a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
index a3552e92a53..bc78a71efad 100644
--- a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
+++ b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
@@ -4002,15 +4002,16 @@ std::error_code BitcodeReader::ParseFunctionBody(Function *F) {
       Type *Ty = nullptr;
       if (OpNum + 3 == Record.size())
         Ty = getTypeByID(Record[OpNum++]);
+      if (!Ty)
+        Ty = cast<PointerType>(Op->getType())->getElementType();
+      else if (Ty != cast<PointerType>(Op->getType())->getElementType())
+        return Error("Explicit load type does not match pointee type of "
+                     "pointer operand");
 
       unsigned Align;
       if (std::error_code EC = parseAlignmentValue(Record[OpNum], Align))
         return EC;
-      I = new LoadInst(Op, "", Record[OpNum+1], Align);
-
-      if (Ty && Ty != I->getType())
-        return Error("Explicit load type does not match pointee type of "
-                     "pointer operand");
+      I = new LoadInst(Ty, Op, "", Record[OpNum + 1], Align);
 
       InstructionList.push_back(I);
       break;