AMDGPU: add missing llvm.amdgcn.{raw,struct}.buffer.atomic.{inc,dec}

Summary:
Wrapping increment/decrement. These aren't exposed by many APIs...

Change-Id: I1df25c7889de5a5ba76468ad8e8a2597efa9af6c

Reviewers: arsenm, tpr, dstuttard

Subscribers: kzhuravl, jvesely, wdng, yaxunl, t-tye, jfb, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D65283

llvm-svn: 367821
diff --git a/llvm/lib/Target/AMDGPU/AMDGPUISelLowering.cpp b/llvm/lib/Target/AMDGPU/AMDGPUISelLowering.cpp
index a5098f4..90e0369 100644
--- a/llvm/lib/Target/AMDGPU/AMDGPUISelLowering.cpp
+++ b/llvm/lib/Target/AMDGPU/AMDGPUISelLowering.cpp
@@ -4354,6 +4354,8 @@
   NODE_NAME_CASE(BUFFER_ATOMIC_AND)
   NODE_NAME_CASE(BUFFER_ATOMIC_OR)
   NODE_NAME_CASE(BUFFER_ATOMIC_XOR)
+  NODE_NAME_CASE(BUFFER_ATOMIC_INC)
+  NODE_NAME_CASE(BUFFER_ATOMIC_DEC)
   NODE_NAME_CASE(BUFFER_ATOMIC_CMPSWAP)
   NODE_NAME_CASE(BUFFER_ATOMIC_FADD)
   NODE_NAME_CASE(BUFFER_ATOMIC_PK_FADD)