[Bitcode] Encode alloca address space

Since D101045, allocas are no longer required to be part of the
default alloca address space. There may be allocas in multiple
different address spaces. However, the bitcode reader would
simply assume the default alloca address space, resulting in
either an error or incorrect IR.

Add an optional record for allocas which encodes the address
space.

1 files changed, 4 insertions, 0 deletions

diff --git a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
index c847118..ec10994 100644
--- a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
+++ b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
@@ -3072,6 +3072,10 @@ void ModuleBitcodeWriter::writeInstruction(const Instruction &I,
     Bitfield::set<APV::ExplicitType>(Record, true);
     Bitfield::set<APV::SwiftError>(Record, AI.isSwiftError());
     Vals.push_back(Record);
+
+    unsigned AS = AI.getAddressSpace();
+    if (AS != M.getDataLayout().getAllocaAddrSpace())
+      Vals.push_back(AS);
     break;
   }