diff --git a/llvm/lib/Target/AMDGPU/AMDGPUAnnotateUniformValues.cpp b/llvm/lib/Target/AMDGPU/AMDGPUAnnotateUniformValues.cpp
--- a/llvm/lib/Target/AMDGPU/AMDGPUAnnotateUniformValues.cpp
+++ b/llvm/lib/Target/AMDGPU/AMDGPUAnnotateUniformValues.cpp
@@ -14,9 +14,11 @@
 
 #include "AMDGPU.h"
 #include "Utils/AMDGPUBaseInfo.h"
+#include "llvm/ADT/SmallSet.h"
 #include "llvm/Analysis/LegacyDivergenceAnalysis.h"
 #include "llvm/Analysis/MemorySSA.h"
 #include "llvm/IR/InstVisitor.h"
+#include "llvm/IR/IntrinsicsAMDGPU.h"
 #include "llvm/InitializePasses.h"
 
 #define DEBUG_TYPE "amdgpu-annotate-uniform"
@@ -70,9 +72,68 @@
   I->setMetadata("amdgpu.noclobber", MDNode::get(I->getContext(), {}));
 }
 
-bool AMDGPUAnnotateUniformValues::isClobberedInFunction(LoadInst * Load) {
-  const MemoryAccess *MA = MSSA->getWalker()->getClobberingMemoryAccess(Load);
-  return !MSSA->isLiveOnEntryDef(MA);
+bool AMDGPUAnnotateUniformValues::isClobberedInFunction(LoadInst *Load) {
+  MemorySSAWalker *Walker = MSSA->getWalker();
+  SmallVector<MemoryAccess *> WorkList{Walker->getClobberingMemoryAccess(Load)};
+  SmallSet<MemoryAccess *, 8> Visited;
+  MemoryLocation Loc(MemoryLocation::get(Load));
+
+  const auto isReallyAClobber = [](MemoryDef *Def) -> bool {
+    Instruction *DefInst = Def->getMemoryInst();
+    LLVM_DEBUG(dbgs() << "  Def: " << *DefInst << '\n');
+
+    if (isa<FenceInst>(DefInst))
+      return false;
+
+    if (const IntrinsicInst *II = dyn_cast<IntrinsicInst>(DefInst)) {
+      switch (II->getIntrinsicID()) {
+      case Intrinsic::amdgcn_s_barrier:
+      case Intrinsic::amdgcn_wave_barrier:
+        return false;
+      default:
+        break;
+      }
+    }
+
+    return true;
+  };
+
+  LLVM_DEBUG(dbgs() << "Checking clobbering of: " << *Load << '\n');
+
+  // Start with a nearest dominating clobbering access, it will be either
+  // live on entry (nothing to do, load is not clobbered), MemoryDef, or
+  // MemoryPhi if several MemoryDefs can define this memory state. In that
+  // case add all Defs to WorkList and continue going up and checking all
+  // the definitions of this memory location until the root. When all the
+  // defs are exhausted and came to the entry state we have no clobber.
+  // Along the scan ignore barriers and fences which are considered clobbers
+  // by the MemorySSA, but not really writing anything into the memory.
+  while (!WorkList.empty()) {
+    MemoryAccess *MA = WorkList.pop_back_val();
+    if (!Visited.insert(MA).second)
+      continue;
+
+    if (MSSA->isLiveOnEntryDef(MA))
+      continue;
+
+    if (MemoryDef *Def = dyn_cast<MemoryDef>(MA)) {
+      if (isReallyAClobber(Def)) {
+        LLVM_DEBUG(dbgs() << "      -> load is clobbered\n");
+        return true;
+      }
+
+      WorkList.push_back(
+          Walker->getClobberingMemoryAccess(Def->getDefiningAccess(), Loc));
+      continue;
+    }
+
+    const MemoryPhi *Phi = cast<MemoryPhi>(MA);
+    for (auto &Use : Phi->incoming_values())
+      WorkList.push_back(cast<MemoryAccess>(&Use));
+  }
+
+  LLVM_DEBUG(dbgs() << "      -> no clobber\n");
+  return false;
 }
 
 void AMDGPUAnnotateUniformValues::visitBranchInst(BranchInst &I) {
diff --git a/llvm/test/CodeGen/AMDGPU/noclobber-barrier.ll b/llvm/test/CodeGen/AMDGPU/noclobber-barrier.ll
new file mode 100644
--- /dev/null
+++ b/llvm/test/CodeGen/AMDGPU/noclobber-barrier.ll
@@ -0,0 +1,438 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt -march=amdgcn -mcpu=gfx900 -amdgpu-aa -amdgpu-aa-wrapper -amdgpu-annotate-uniform -S < %s | FileCheck %s
+; RUN: llc -march=amdgcn -mcpu=gfx900 -verify-machineinstrs < %s | FileCheck -check-prefix=GCN %s
+
+; Check that barrier or fence in between of loads is not considered a clobber
+; for the purpose of converting vector loads into scalar.
+
+@LDS = linkonce_odr hidden local_unnamed_addr addrspace(3) global i32 undef
+
+; GCN-LABEL: {{^}}simple_barrier:
+; GCN: s_load_dword s
+; GCN: s_waitcnt lgkmcnt(0)
+; GCN: s_barrier
+; GCN: s_waitcnt lgkmcnt(0)
+; GCN: ; wave barrier
+; GCN-NOT: global_load_dword
+; GCN: s_load_dword s
+; GCN-NOT: global_load_dword
+; GCN: global_store_dword
+define amdgpu_kernel void @simple_barrier(i32 addrspace(1)* %arg) {
+; CHECK-LABEL: @simple_barrier(
+; CHECK-NEXT:  bb:
+; CHECK-NEXT:    [[TMP0:%.*]] = getelementptr i32, i32 addrspace(1)* [[ARG:%.*]], i64 0, !amdgpu.uniform !0, !amdgpu.noclobber !0
+; CHECK-NEXT:    [[I:%.*]] = load i32, i32 addrspace(1)* [[TMP0]], align 4
+; CHECK-NEXT:    fence syncscope("workgroup") release
+; CHECK-NEXT:    tail call void @llvm.amdgcn.s.barrier()
+; CHECK-NEXT:    fence syncscope("workgroup") acquire
+; CHECK-NEXT:    tail call void @llvm.amdgcn.wave.barrier()
+; CHECK-NEXT:    [[I1:%.*]] = getelementptr inbounds i32, i32 addrspace(1)* [[ARG]], i64 1, !amdgpu.uniform !0, !amdgpu.noclobber !0
+; CHECK-NEXT:    [[I2:%.*]] = load i32, i32 addrspace(1)* [[I1]], align 4
+; CHECK-NEXT:    [[I3:%.*]] = add i32 [[I2]], [[I]]
+; CHECK-NEXT:    [[I4:%.*]] = getelementptr inbounds i32, i32 addrspace(1)* [[ARG]], i64 2
+; CHECK-NEXT:    store i32 [[I3]], i32 addrspace(1)* [[I4]], align 4
+; CHECK-NEXT:    ret void
+;
+bb:
+  %i = load i32, i32 addrspace(1)* %arg, align 4
+  fence syncscope("workgroup") release
+  tail call void @llvm.amdgcn.s.barrier()
+  fence syncscope("workgroup") acquire
+  tail call void @llvm.amdgcn.wave.barrier()
+  %i1 = getelementptr inbounds i32, i32 addrspace(1)* %arg, i64 1
+  %i2 = load i32, i32 addrspace(1)* %i1, align 4
+  %i3 = add i32 %i2, %i
+  %i4 = getelementptr inbounds i32, i32 addrspace(1)* %arg, i64 2
+  store i32 %i3, i32 addrspace(1)* %i4, align 4
+  ret void
+}
+
+; GCN-LABEL: {{^}}memory_phi_no_clobber:
+; GCN: s_load_dword s
+; GCN: s_waitcnt lgkmcnt(0)
+; GCN: s_waitcnt lgkmcnt(0)
+; GCN: s_barrier
+; GCN-NOT: global_load_dword
+; GCN: s_load_dword s
+; GCN-NOT: global_load_dword
+; GCN: global_store_dword
+define amdgpu_kernel void @memory_phi_no_clobber(i32 addrspace(1)* %arg) {
+; CHECK-LABEL: @memory_phi_no_clobber(
+; CHECK-NEXT:  bb:
+; CHECK-NEXT:    [[TMP0:%.*]] = getelementptr i32, i32 addrspace(1)* [[ARG:%.*]], i64 0, !amdgpu.uniform !0, !amdgpu.noclobber !0
+; CHECK-NEXT:    [[I:%.*]] = load i32, i32 addrspace(1)* [[TMP0]], align 4
+; CHECK-NEXT:    br i1 undef, label [[IF_THEN:%.*]], label [[IF_ELSE:%.*]], !amdgpu.uniform !0
+; CHECK:       if.then:
+; CHECK-NEXT:    tail call void @llvm.amdgcn.s.barrier()
+; CHECK-NEXT:    br label [[IF_END:%.*]], !amdgpu.uniform !0
+; CHECK:       if.else:
+; CHECK-NEXT:    fence syncscope("workgroup") release
+; CHECK-NEXT:    br label [[IF_END]], !amdgpu.uniform !0
+; CHECK:       if.end:
+; CHECK-NEXT:    [[I1:%.*]] = getelementptr inbounds i32, i32 addrspace(1)* [[ARG]], i64 1, !amdgpu.uniform !0, !amdgpu.noclobber !0
+; CHECK-NEXT:    [[I2:%.*]] = load i32, i32 addrspace(1)* [[I1]], align 4
+; CHECK-NEXT:    [[I3:%.*]] = add i32 [[I2]], [[I]]
+; CHECK-NEXT:    [[I4:%.*]] = getelementptr inbounds i32, i32 addrspace(1)* [[ARG]], i64 2
+; CHECK-NEXT:    store i32 [[I3]], i32 addrspace(1)* [[I4]], align 4
+; CHECK-NEXT:    ret void
+;
+bb:
+  %i = load i32, i32 addrspace(1)* %arg, align 4
+  br i1 undef, label %if.then, label %if.else
+
+if.then:
+  tail call void @llvm.amdgcn.s.barrier()
+  br label %if.end
+
+if.else:
+  fence syncscope("workgroup") release
+  br label %if.end
+
+if.end:
+  %i1 = getelementptr inbounds i32, i32 addrspace(1)* %arg, i64 1
+  %i2 = load i32, i32 addrspace(1)* %i1, align 4
+  %i3 = add i32 %i2, %i
+  %i4 = getelementptr inbounds i32, i32 addrspace(1)* %arg, i64 2
+  store i32 %i3, i32 addrspace(1)* %i4, align 4
+  ret void
+}
+
+; GCN-LABEL: {{^}}memory_phi_clobber1:
+; GCN: s_load_dword s
+; GCN: s_barrier
+; GCN: global_store_dword
+; GCN: global_load_dword
+; GCN: global_store_dword
+define amdgpu_kernel void @memory_phi_clobber1(i32 addrspace(1)* %arg) {
+; CHECK-LABEL: @memory_phi_clobber1(
+; CHECK-NEXT:  bb:
+; CHECK-NEXT:    [[TMP0:%.*]] = getelementptr i32, i32 addrspace(1)* [[ARG:%.*]], i64 0, !amdgpu.uniform !0, !amdgpu.noclobber !0
+; CHECK-NEXT:    [[I:%.*]] = load i32, i32 addrspace(1)* [[TMP0]], align 4
+; CHECK-NEXT:    br i1 undef, label [[IF_THEN:%.*]], label [[IF_ELSE:%.*]], !amdgpu.uniform !0
+; CHECK:       if.then:
+; CHECK-NEXT:    [[GEP:%.*]] = getelementptr inbounds i32, i32 addrspace(1)* [[ARG]], i64 3
+; CHECK-NEXT:    store i32 1, i32 addrspace(1)* [[GEP]], align 4
+; CHECK-NEXT:    br label [[IF_END:%.*]], !amdgpu.uniform !0
+; CHECK:       if.else:
+; CHECK-NEXT:    tail call void @llvm.amdgcn.s.barrier()
+; CHECK-NEXT:    br label [[IF_END]], !amdgpu.uniform !0
+; CHECK:       if.end:
+; CHECK-NEXT:    [[I1:%.*]] = getelementptr inbounds i32, i32 addrspace(1)* [[ARG]], i64 1, !amdgpu.uniform !0
+; CHECK-NEXT:    [[I2:%.*]] = load i32, i32 addrspace(1)* [[I1]], align 4
+; CHECK-NEXT:    [[I3:%.*]] = add i32 [[I2]], [[I]]
+; CHECK-NEXT:    [[I4:%.*]] = getelementptr inbounds i32, i32 addrspace(1)* [[ARG]], i64 2
+; CHECK-NEXT:    store i32 [[I3]], i32 addrspace(1)* [[I4]], align 4
+; CHECK-NEXT:    ret void
+;
+bb:
+  %i = load i32, i32 addrspace(1)* %arg, align 4
+  br i1 undef, label %if.then, label %if.else
+
+if.then:
+  %gep = getelementptr inbounds i32, i32 addrspace(1)* %arg, i64 3
+  store i32 1, i32 addrspace(1)* %gep, align 4
+  br label %if.end
+
+if.else:
+  tail call void @llvm.amdgcn.s.barrier()
+  br label %if.end
+
+if.end:
+  %i1 = getelementptr inbounds i32, i32 addrspace(1)* %arg, i64 1
+  %i2 = load i32, i32 addrspace(1)* %i1, align 4
+  %i3 = add i32 %i2, %i
+  %i4 = getelementptr inbounds i32, i32 addrspace(1)* %arg, i64 2
+  store i32 %i3, i32 addrspace(1)* %i4, align 4
+  ret void
+}
+
+; GCN-LABEL: {{^}}memory_phi_clobber2:
+; GCN-DAG: s_load_dword s
+; GCN-DAG: global_store_dword
+; GCN: s_barrier
+; GCN: global_load_dword
+; GCN: global_store_dword
+define amdgpu_kernel void @memory_phi_clobber2(i32 addrspace(1)* %arg) {
+; CHECK-LABEL: @memory_phi_clobber2(
+; CHECK-NEXT:  bb:
+; CHECK-NEXT:    [[TMP0:%.*]] = getelementptr i32, i32 addrspace(1)* [[ARG:%.*]], i64 0, !amdgpu.uniform !0, !amdgpu.noclobber !0
+; CHECK-NEXT:    [[I:%.*]] = load i32, i32 addrspace(1)* [[TMP0]], align 4
+; CHECK-NEXT:    br i1 undef, label [[IF_THEN:%.*]], label [[IF_ELSE:%.*]], !amdgpu.uniform !0
+; CHECK:       if.then:
+; CHECK-NEXT:    tail call void @llvm.amdgcn.s.barrier()
+; CHECK-NEXT:    br label [[IF_END:%.*]], !amdgpu.uniform !0
+; CHECK:       if.else:
+; CHECK-NEXT:    [[GEP:%.*]] = getelementptr inbounds i32, i32 addrspace(1)* [[ARG]], i64 3
+; CHECK-NEXT:    store i32 1, i32 addrspace(1)* [[GEP]], align 4
+; CHECK-NEXT:    br label [[IF_END]], !amdgpu.uniform !0
+; CHECK:       if.end:
+; CHECK-NEXT:    [[I1:%.*]] = getelementptr inbounds i32, i32 addrspace(1)* [[ARG]], i64 1, !amdgpu.uniform !0
+; CHECK-NEXT:    [[I2:%.*]] = load i32, i32 addrspace(1)* [[I1]], align 4
+; CHECK-NEXT:    [[I3:%.*]] = add i32 [[I2]], [[I]]
+; CHECK-NEXT:    [[I4:%.*]] = getelementptr inbounds i32, i32 addrspace(1)* [[ARG]], i64 2
+; CHECK-NEXT:    store i32 [[I3]], i32 addrspace(1)* [[I4]], align 4
+; CHECK-NEXT:    ret void
+;
+bb:
+  %i = load i32, i32 addrspace(1)* %arg, align 4
+  br i1 undef, label %if.then, label %if.else
+
+if.then:
+  tail call void @llvm.amdgcn.s.barrier()
+  br label %if.end
+
+if.else:
+  %gep = getelementptr inbounds i32, i32 addrspace(1)* %arg, i64 3
+  store i32 1, i32 addrspace(1)* %gep, align 4
+  br label %if.end
+
+if.end:
+  %i1 = getelementptr inbounds i32, i32 addrspace(1)* %arg, i64 1
+  %i2 = load i32, i32 addrspace(1)* %i1, align 4
+  %i3 = add i32 %i2, %i
+  %i4 = getelementptr inbounds i32, i32 addrspace(1)* %arg, i64 2
+  store i32 %i3, i32 addrspace(1)* %i4, align 4
+  ret void
+}
+
+; GCN-LABEL: {{^}}no_clobbering_loop1:
+; GCN: s_load_dword s
+; GCN: s_load_dword s
+; GCN-NOT: global_load_dword
+; GCN: global_store_dword
+define amdgpu_kernel void @no_clobbering_loop1(i32 addrspace(1)* %arg, i1 %cc) {
+; CHECK-LABEL: @no_clobbering_loop1(
+; CHECK-NEXT:  bb:
+; CHECK-NEXT:    [[TMP0:%.*]] = getelementptr i32, i32 addrspace(1)* [[ARG:%.*]], i64 0, !amdgpu.uniform !0, !amdgpu.noclobber !0
+; CHECK-NEXT:    [[I:%.*]] = load i32, i32 addrspace(1)* [[TMP0]], align 4
+; CHECK-NEXT:    br label [[WHILE_COND:%.*]], !amdgpu.uniform !0
+; CHECK:       while.cond:
+; CHECK-NEXT:    [[I1:%.*]] = getelementptr inbounds i32, i32 addrspace(1)* [[ARG]], i64 1, !amdgpu.uniform !0, !amdgpu.noclobber !0
+; CHECK-NEXT:    [[I2:%.*]] = load i32, i32 addrspace(1)* [[I1]], align 4
+; CHECK-NEXT:    [[I3:%.*]] = add i32 [[I2]], [[I]]
+; CHECK-NEXT:    [[I4:%.*]] = getelementptr inbounds i32, i32 addrspace(1)* [[ARG]], i64 2
+; CHECK-NEXT:    store i32 [[I3]], i32 addrspace(1)* [[I4]], align 4
+; CHECK-NEXT:    tail call void @llvm.amdgcn.wave.barrier()
+; CHECK-NEXT:    br i1 [[CC:%.*]], label [[WHILE_COND]], label [[END:%.*]], !amdgpu.uniform !0
+; CHECK:       end:
+; CHECK-NEXT:    ret void
+;
+bb:
+  %i = load i32, i32 addrspace(1)* %arg, align 4
+  br label %while.cond
+
+while.cond:
+  %i1 = getelementptr inbounds i32, i32 addrspace(1)* %arg, i64 1
+  %i2 = load i32, i32 addrspace(1)* %i1, align 4
+  %i3 = add i32 %i2, %i
+  %i4 = getelementptr inbounds i32, i32 addrspace(1)* %arg, i64 2
+  store i32 %i3, i32 addrspace(1)* %i4, align 4
+  tail call void @llvm.amdgcn.wave.barrier()
+  br i1 %cc, label %while.cond, label %end
+
+end:
+  ret void
+}
+
+; GCN-LABEL: {{^}}no_clobbering_loop2:
+; GCN: s_load_dword s
+; GCN: s_load_dword s
+; GCN-NOT: global_load_dword
+; GCN: global_store_dword
+define amdgpu_kernel void @no_clobbering_loop2(i32 addrspace(1)* noalias %arg, i32 addrspace(1)* noalias %out, i32 %n) {
+; CHECK-LABEL: @no_clobbering_loop2(
+; CHECK-NEXT:  bb:
+; CHECK-NEXT:    [[TMP0:%.*]] = getelementptr i32, i32 addrspace(1)* [[ARG:%.*]], i64 0, !amdgpu.uniform !0, !amdgpu.noclobber !0
+; CHECK-NEXT:    [[I:%.*]] = load i32, i32 addrspace(1)* [[TMP0]], align 4
+; CHECK-NEXT:    br label [[WHILE_COND:%.*]], !amdgpu.uniform !0
+; CHECK:       while.cond:
+; CHECK-NEXT:    [[C:%.*]] = phi i32 [ 0, [[BB:%.*]] ], [ [[INC:%.*]], [[WHILE_COND]] ]
+; CHECK-NEXT:    [[ACC:%.*]] = phi i32 [ [[I]], [[BB]] ], [ [[I3:%.*]], [[WHILE_COND]] ]
+; CHECK-NEXT:    [[I1:%.*]] = getelementptr inbounds i32, i32 addrspace(1)* [[ARG]], i32 [[C]], !amdgpu.uniform !0, !amdgpu.noclobber !0
+; CHECK-NEXT:    [[I2:%.*]] = load i32, i32 addrspace(1)* [[I1]], align 4
+; CHECK-NEXT:    [[I3]] = add i32 [[I2]], [[ACC]]
+; CHECK-NEXT:    tail call void @llvm.amdgcn.wave.barrier()
+; CHECK-NEXT:    [[INC]] = add nuw nsw i32 [[C]], 1
+; CHECK-NEXT:    [[CC:%.*]] = icmp eq i32 [[INC]], [[N:%.*]]
+; CHECK-NEXT:    br i1 [[CC]], label [[WHILE_COND]], label [[END:%.*]], !amdgpu.uniform !0
+; CHECK:       end:
+; CHECK-NEXT:    store i32 [[I3]], i32 addrspace(1)* [[OUT:%.*]], align 4
+; CHECK-NEXT:    ret void
+;
+bb:
+  %i = load i32, i32 addrspace(1)* %arg, align 4
+  br label %while.cond
+
+while.cond:
+  %c = phi i32 [ 0, %bb ], [ %inc, %while.cond ]
+  %acc = phi i32 [ %i, %bb ], [ %i3, %while.cond ]
+  %i1 = getelementptr inbounds i32, i32 addrspace(1)* %arg, i32 %c
+  %i2 = load i32, i32 addrspace(1)* %i1, align 4
+  %i3 = add i32 %i2, %acc
+  tail call void @llvm.amdgcn.wave.barrier()
+  %inc = add nuw nsw i32 %c, 1
+  %cc = icmp eq i32 %inc, %n
+  br i1 %cc, label %while.cond, label %end
+
+end:
+  store i32 %i3, i32 addrspace(1)* %out, align 4
+  ret void
+}
+
+; GCN-LABEL: {{^}}clobbering_loop:
+; GCN: s_load_dword s
+; GCN: global_load_dword
+; GCN: global_store_dword
+define amdgpu_kernel void @clobbering_loop(i32 addrspace(1)* %arg, i32 addrspace(1)* %out, i1 %cc) {
+; CHECK-LABEL: @clobbering_loop(
+; CHECK-NEXT:  bb:
+; CHECK-NEXT:    [[TMP0:%.*]] = getelementptr i32, i32 addrspace(1)* [[ARG:%.*]], i64 0, !amdgpu.uniform !0, !amdgpu.noclobber !0
+; CHECK-NEXT:    [[I:%.*]] = load i32, i32 addrspace(1)* [[TMP0]], align 4
+; CHECK-NEXT:    br label [[WHILE_COND:%.*]], !amdgpu.uniform !0
+; CHECK:       while.cond:
+; CHECK-NEXT:    [[I1:%.*]] = getelementptr inbounds i32, i32 addrspace(1)* [[ARG]], i64 1, !amdgpu.uniform !0
+; CHECK-NEXT:    [[I2:%.*]] = load i32, i32 addrspace(1)* [[I1]], align 4
+; CHECK-NEXT:    [[I3:%.*]] = add i32 [[I2]], [[I]]
+; CHECK-NEXT:    [[I4:%.*]] = getelementptr inbounds i32, i32 addrspace(1)* [[OUT:%.*]], i64 1
+; CHECK-NEXT:    store i32 [[I3]], i32 addrspace(1)* [[I4]], align 4
+; CHECK-NEXT:    tail call void @llvm.amdgcn.wave.barrier()
+; CHECK-NEXT:    br i1 [[CC:%.*]], label [[WHILE_COND]], label [[END:%.*]], !amdgpu.uniform !0
+; CHECK:       end:
+; CHECK-NEXT:    ret void
+;
+bb:
+  %i = load i32, i32 addrspace(1)* %arg, align 4
+  br label %while.cond
+
+while.cond:
+  %i1 = getelementptr inbounds i32, i32 addrspace(1)* %arg, i64 1
+  %i2 = load i32, i32 addrspace(1)* %i1, align 4
+  %i3 = add i32 %i2, %i
+  %i4 = getelementptr inbounds i32, i32 addrspace(1)* %out, i64 1
+  store i32 %i3, i32 addrspace(1)* %i4, align 4
+  tail call void @llvm.amdgcn.wave.barrier()
+  br i1 %cc, label %while.cond, label %end
+
+end:
+  ret void
+}
+
+; GCN-LABEL: {{^}}clobber_by_atomic_load:
+; GCN: s_load_dword s
+; GCN: global_load_dword {{.*}} glc
+; GCN: global_load_dword
+; GCN: global_store_dword
+define amdgpu_kernel void @clobber_by_atomic_load(i32 addrspace(1)* %arg) {
+; CHECK-LABEL: @clobber_by_atomic_load(
+; CHECK-NEXT:  bb:
+; CHECK-NEXT:    [[TMP0:%.*]] = getelementptr i32, i32 addrspace(1)* [[ARG:%.*]], i64 0, !amdgpu.uniform !0, !amdgpu.noclobber !0
+; CHECK-NEXT:    [[I:%.*]] = load i32, i32 addrspace(1)* [[TMP0]], align 4
+; CHECK-NEXT:    [[GEP:%.*]] = getelementptr inbounds i32, i32 addrspace(1)* [[ARG]], i64 2, !amdgpu.uniform !0, !amdgpu.noclobber !0
+; CHECK-NEXT:    [[VAL:%.*]] = load atomic i32, i32 addrspace(1)* [[GEP]] seq_cst, align 4
+; CHECK-NEXT:    [[I1:%.*]] = getelementptr inbounds i32, i32 addrspace(1)* [[ARG]], i64 3, !amdgpu.uniform !0
+; CHECK-NEXT:    [[I2:%.*]] = load i32, i32 addrspace(1)* [[I1]], align 4
+; CHECK-NEXT:    [[I3:%.*]] = add i32 [[I2]], [[I]]
+; CHECK-NEXT:    [[I4:%.*]] = getelementptr inbounds i32, i32 addrspace(1)* [[ARG]], i64 4
+; CHECK-NEXT:    store i32 [[I3]], i32 addrspace(1)* [[I4]], align 4
+; CHECK-NEXT:    ret void
+;
+bb:
+  %i = load i32, i32 addrspace(1)* %arg, align 4
+  %gep = getelementptr inbounds i32, i32 addrspace(1)* %arg, i64 2
+  %val = load atomic i32, i32 addrspace(1)* %gep  seq_cst, align 4
+  %i1 = getelementptr inbounds i32, i32 addrspace(1)* %arg, i64 3
+  %i2 = load i32, i32 addrspace(1)* %i1, align 4
+  %i3 = add i32 %i2, %i
+  %i4 = getelementptr inbounds i32, i32 addrspace(1)* %arg, i64 4
+  store i32 %i3, i32 addrspace(1)* %i4, align 4
+  ret void
+}
+
+; GCN-LABEL: {{^}}no_alias_store:
+; GCN: ds_write_b32
+; GCN: s_barrier
+; GCN: s_load_dword s
+; GCN-NOT: global_load_dword
+; GCN: global_store_dword
+define protected amdgpu_kernel void @no_alias_store(i32 addrspace(1)* %in, i32 addrspace(1)* %out) {
+; CHECK-LABEL: @no_alias_store(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    store i32 0, i32 addrspace(3)* @LDS, align 4
+; CHECK-NEXT:    fence syncscope("workgroup") release
+; CHECK-NEXT:    tail call void @llvm.amdgcn.s.barrier()
+; CHECK-NEXT:    fence syncscope("workgroup") acquire
+; CHECK-NEXT:    [[GEP:%.*]] = getelementptr inbounds i32, i32 addrspace(1)* [[IN:%.*]], i64 0, !amdgpu.uniform !0, !amdgpu.noclobber !0
+; CHECK-NEXT:    [[LD:%.*]] = load i32, i32 addrspace(1)* [[GEP]], align 4
+; CHECK-NEXT:    store i32 [[LD]], i32 addrspace(1)* [[OUT:%.*]], align 4
+; CHECK-NEXT:    ret void
+;
+entry:
+  store i32 0, i32 addrspace(3)* @LDS, align 4
+  fence syncscope("workgroup") release
+  tail call void @llvm.amdgcn.s.barrier()
+  fence syncscope("workgroup") acquire
+  %gep = getelementptr inbounds i32, i32 addrspace(1)* %in, i64 0
+  %ld = load i32, i32 addrspace(1)* %gep, align 4
+  store i32 %ld, i32 addrspace(1)* %out, align 4
+  ret void
+}
+
+; GCN-LABEL: {{^}}may_alias_store:
+; GCN: global_store_dword
+; GCN: s_barrier
+; GCN: global_load_dword
+; GCN: global_store_dword
+define protected amdgpu_kernel void @may_alias_store(i32 addrspace(1)* %in, i32 addrspace(1)* %out) {
+; CHECK-LABEL: @may_alias_store(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    store i32 0, i32 addrspace(1)* [[OUT:%.*]], align 4
+; CHECK-NEXT:    fence syncscope("workgroup") release
+; CHECK-NEXT:    tail call void @llvm.amdgcn.s.barrier()
+; CHECK-NEXT:    fence syncscope("workgroup") acquire
+; CHECK-NEXT:    [[GEP:%.*]] = getelementptr inbounds i32, i32 addrspace(1)* [[IN:%.*]], i64 0, !amdgpu.uniform !0
+; CHECK-NEXT:    [[LD:%.*]] = load i32, i32 addrspace(1)* [[GEP]], align 4
+; CHECK-NEXT:    store i32 [[LD]], i32 addrspace(1)* [[OUT]], align 4
+; CHECK-NEXT:    ret void
+;
+entry:
+  store i32 0, i32 addrspace(1)* %out, align 4
+  fence syncscope("workgroup") release
+  tail call void @llvm.amdgcn.s.barrier()
+  fence syncscope("workgroup") acquire
+  %gep = getelementptr inbounds i32, i32 addrspace(1)* %in, i64 0
+  %ld = load i32, i32 addrspace(1)* %gep, align 4
+  store i32 %ld, i32 addrspace(1)* %out, align 4
+  ret void
+}
+
+; GCN-LABEL: {{^}}no_alias_volatile_store:
+; GCN: ds_write_b32
+; GCN: s_barrier
+; GCN: s_load_dword s
+; GCN-NOT: global_load_dword
+; GCN: global_store_dword
+define protected amdgpu_kernel void @no_alias_volatile_store(i32 addrspace(1)* %in, i32 addrspace(1)* %out) {
+; CHECK-LABEL: @no_alias_volatile_store(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    store volatile i32 0, i32 addrspace(3)* @LDS, align 4
+; CHECK-NEXT:    fence syncscope("workgroup") release
+; CHECK-NEXT:    tail call void @llvm.amdgcn.s.barrier()
+; CHECK-NEXT:    fence syncscope("workgroup") acquire
+; CHECK-NEXT:    [[GEP:%.*]] = getelementptr inbounds i32, i32 addrspace(1)* [[IN:%.*]], i64 0, !amdgpu.uniform !0, !amdgpu.noclobber !0
+; CHECK-NEXT:    [[LD:%.*]] = load i32, i32 addrspace(1)* [[GEP]], align 4
+; CHECK-NEXT:    store i32 [[LD]], i32 addrspace(1)* [[OUT:%.*]], align 4
+; CHECK-NEXT:    ret void
+;
+entry:
+  store volatile i32 0, i32 addrspace(3)* @LDS, align 4
+  fence syncscope("workgroup") release
+  tail call void @llvm.amdgcn.s.barrier()
+  fence syncscope("workgroup") acquire
+  %gep = getelementptr inbounds i32, i32 addrspace(1)* %in, i64 0
+  %ld = load i32, i32 addrspace(1)* %gep, align 4
+  store i32 %ld, i32 addrspace(1)* %out, align 4
+  ret void
+}
+
+declare void @llvm.amdgcn.s.barrier()
+declare void @llvm.amdgcn.wave.barrier()