[SystemZ] Support ATOMIC_FENCE
A cross-thread sequentially consistent fence should be lowered into
z/Architecture's BCR serialization instruction, instead of causing a
fatal error in the back-end.
Author: bryanpkc
Differential Revision: http://reviews.llvm.org/D18644
llvm-svn: 265292
diff --git a/llvm/lib/Target/SystemZ/SystemZAsmPrinter.cpp b/llvm/lib/Target/SystemZ/SystemZAsmPrinter.cpp
index 7527311..be729d3 100644
--- a/llvm/lib/Target/SystemZ/SystemZAsmPrinter.cpp
+++ b/llvm/lib/Target/SystemZ/SystemZAsmPrinter.cpp
@@ -260,6 +260,11 @@
.addImm(15).addReg(SystemZ::R0D);
break;
+ // Emit nothing here but a comment if we can.
+ case SystemZ::MemBarrier:
+ OutStreamer->emitRawComment("MEMBARRIER");
+ return;
+
default:
Lower.lower(MI, LoweredMI);
break;