Index: include/llvm/Analysis/DivergenceAnalysis.h
===================================================================
--- include/llvm/Analysis/DivergenceAnalysis.h
+++ include/llvm/Analysis/DivergenceAnalysis.h
@@ -35,10 +35,16 @@
   // Print all divergent branches in the function.
   void print(raw_ostream &OS, const Module *) const override;
 
-  // Returns true if V is divergent.
+  // Returns true if V is divergent at its definition.
+  //
+  // Even if this function returns false, V may still be divergent when used
+  // in a different basic block.
   bool isDivergent(const Value *V) const { return DivergentValues.count(V); }
 
   // Returns true if V is uniform/non-divergent.
+  //
+  // Even if this function returns true, V may still be divergent when used
+  // in a different basic block.
   bool isUniform(const Value *V) const { return !isDivergent(V); }
 
 private:
Index: lib/Transforms/Scalar/StructurizeCFG.cpp
===================================================================
--- lib/Transforms/Scalar/StructurizeCFG.cpp
+++ lib/Transforms/Scalar/StructurizeCFG.cpp
@@ -55,6 +55,12 @@
 
 namespace {
 
+static cl::opt<bool> ForceSkipUniformRegions(
+  "structurizecfg-skip-uniform-regions",
+  cl::Hidden,
+  cl::desc("Force whether the StructurizeCFG pass skips uniform regions"),
+  cl::init(false));
+
 // Definition of the complex types used in this pass.
 
 using BBValuePair = std::pair<BasicBlock *, Value *>;
@@ -242,8 +248,11 @@
 public:
   static char ID;
 
-  explicit StructurizeCFG(bool SkipUniformRegions = false)
-      : RegionPass(ID), SkipUniformRegions(SkipUniformRegions) {
+  explicit StructurizeCFG(bool SkipUniformRegions_ = false)
+      : RegionPass(ID),
+        SkipUniformRegions(SkipUniformRegions_) {
+    if (ForceSkipUniformRegions.getNumOccurrences())
+      SkipUniformRegions = ForceSkipUniformRegions.getValue();
     initializeStructurizeCFGPass(*PassRegistry::getPassRegistry());
   }
 
@@ -885,7 +894,7 @@
     if (!Br || !Br->isConditional())
       continue;
 
-    if (!DA.isUniform(Br->getCondition()))
+    if (!DA.isUniform(Br))
       return false;
     DEBUG(dbgs() << "BB: " << BB->getName() << " has uniform terminator\n");
   }
Index: test/CodeGen/AMDGPU/control-flow-optnone.ll
===================================================================
--- test/CodeGen/AMDGPU/control-flow-optnone.ll
+++ test/CodeGen/AMDGPU/control-flow-optnone.ll
@@ -15,8 +15,8 @@
 ; GCN: s_mov_b64 exec
 
 ; GCN: s_or_b64 exec, exec
-; GCN: v_cmp_eq_u32
-; GCN: s_cbranch_vccnz
+; GCN: s_cmp_eq_u32
+; GCN: s_cbranch_scc1
 ; GCN-NEXT: s_branch
 define amdgpu_kernel void @copytoreg_divergent_brcond(i32 %arg, i32 %arg1, i32 %arg2) #0 {
 bb:
Index: test/Transforms/StructurizeCFG/AMDGPU/uniform-regions.ll
===================================================================
--- /dev/null
+++ test/Transforms/StructurizeCFG/AMDGPU/uniform-regions.ll
@@ -0,0 +1,50 @@
+; RUN: opt -mtriple=amdgcn-- -S -o - -structurizecfg -structurizecfg-skip-uniform-regions < %s | FileCheck %s
+
+; CHECK-LABEL: @uniform(
+; CHECK: entry:
+; CHECK:   br i1 %cc, label %if, label %end, !structurizecfg.uniform !0
+; CHECK: if:
+; CHECK:   br label %end, !structurizecfg.uniform !0
+define amdgpu_cs void @uniform(i32 inreg %v) {
+entry:
+  %cc = icmp eq i32 %v, 0
+  br i1 %cc, label %if, label %end
+
+if:
+  br label %end
+
+end:
+  ret void
+}
+
+; CHECK-LABEL: @nonuniform(
+; CHECK-NOT: !structurizecfg
+define amdgpu_cs void @nonuniform(i32 addrspace(2)* %ptr) {
+entry:
+  br label %for.body
+
+for.body:
+  %i = phi i32 [0, %entry], [%i.inc, %end.loop]
+  %cc = icmp ult i32 %i, 4
+  br i1 %cc, label %mid.loop, label %for.end
+
+mid.loop:
+  %v = call i32 @llvm.amdgcn.workitem.id.x()
+  %cc2 = icmp eq i32 %v, 0
+  br i1 %cc2, label %end.loop, label %for.end
+
+end.loop:
+  %i.inc = add i32 %i, 1
+  br label %for.body
+
+for.end:
+  br i1 %cc, label %if, label %end
+
+if:
+  br label %end
+
+end:
+  ret void
+}
+
+declare i32 @llvm.amdgcn.workitem.id.x()