Index: include/llvm/CodeGen/BasicTTIImpl.h
===================================================================
--- include/llvm/CodeGen/BasicTTIImpl.h
+++ include/llvm/CodeGen/BasicTTIImpl.h
@@ -413,6 +413,12 @@
       if (TLI->isZExtFree(OpTy, Ty))
         return TargetTransformInfo::TCC_Free;
       return TargetTransformInfo::TCC_Basic;
+
+    case Instruction::AddrSpaceCast:
+      if (TLI->isFreeAddrSpaceCast(OpTy->getPointerAddressSpace(),
+                                   Ty->getPointerAddressSpace()))
+        return TargetTransformInfo::TCC_Free;
+      return TargetTransformInfo::TCC_Basic;
     }
 
     return BaseT::getOperationCost(Opcode, Ty, OpTy);
@@ -656,7 +662,7 @@
       return 0;
 
     if (Opcode == Instruction::AddrSpaceCast &&
-        TLI->isNoopAddrSpaceCast(Src->getPointerAddressSpace(),
+        TLI->isFreeAddrSpaceCast(Src->getPointerAddressSpace(),
                                  Dst->getPointerAddressSpace()))
       return 0;
 
Index: include/llvm/CodeGen/TargetLowering.h
===================================================================
--- include/llvm/CodeGen/TargetLowering.h
+++ include/llvm/CodeGen/TargetLowering.h
@@ -1586,6 +1586,12 @@
     return isNoopAddrSpaceCast(SrcAS, DestAS);
   }
 
+  /// Returns true if a cast from SrcAS to DestAS is free, but not necessarily a
+  /// no-op. e.g. a free truncate from a 64-bit to 32-bit pointer.
+  bool isFreeAddrSpaceCast(unsigned SrcAS, unsigned DestAS) const {
+    return isCheapAddrSpaceCast(SrcAS, DestAS);
+  }
+
   /// Return true if the pointer arguments to CI should be aligned by aligning
   /// the object whose address is being passed. If so then MinSize is set to the
   /// minimum size the object must be to be aligned and PrefAlign is set to the
Index: test/Analysis/CostModel/AMDGPU/addrspacecast.ll
===================================================================
--- test/Analysis/CostModel/AMDGPU/addrspacecast.ll
+++ test/Analysis/CostModel/AMDGPU/addrspacecast.ll
@@ -1,45 +1,66 @@
 ; RUN: opt -cost-model -analyze -mtriple=amdgcn-unknown-amdhsa -mcpu=kaveri < %s | FileCheck %s
 
-; CHECK: 'addrspacecast_global_to_flat'
+; CHECK-LABEL: 'addrspacecast_global_to_flat'
 ; CHECK: estimated cost of 0 for {{.*}} addrspacecast i8 addrspace(1)* %ptr to i8*
 define i8* @addrspacecast_global_to_flat(i8 addrspace(1)* %ptr) #0 {
   %cast = addrspacecast i8 addrspace(1)* %ptr to i8*
   ret i8* %cast
 }
 
-; CHECK: 'addrspacecast_global_to_flat_v2'
+; CHECK-LABEL: 'addrspacecast_global_to_flat_v2'
 ; CHECK: estimated cost of 0 for {{.*}} addrspacecast <2 x i8 addrspace(1)*> %ptr to <2 x i8*>
 define <2 x i8*> @addrspacecast_global_to_flat_v2(<2 x i8 addrspace(1)*> %ptr) #0 {
   %cast = addrspacecast <2 x i8 addrspace(1)*> %ptr to <2 x i8*>
   ret <2 x i8*> %cast
 }
 
-; CHECK: 'addrspacecast_global_to_flat_v32'
+; CHECK-LABEL: 'addrspacecast_global_to_flat_v32'
 ; CHECK: estimated cost of 0 for {{.*}} addrspacecast <32 x i8 addrspace(1)*> %ptr to <32 x i8*>
 define <32 x i8*> @addrspacecast_global_to_flat_v32(<32 x i8 addrspace(1)*> %ptr) #0 {
   %cast = addrspacecast <32 x i8 addrspace(1)*> %ptr to <32 x i8*>
   ret <32 x i8*> %cast
 }
 
-; CHECK: 'addrspacecast_local_to_flat'
+; CHECK-LABEL: 'addrspacecast_local_to_flat'
 ; CHECK: estimated cost of 1 for {{.*}} addrspacecast i8 addrspace(3)* %ptr to i8*
 define i8* @addrspacecast_local_to_flat(i8 addrspace(3)* %ptr) #0 {
   %cast = addrspacecast i8 addrspace(3)* %ptr to i8*
   ret i8* %cast
 }
 
-; CHECK: 'addrspacecast_local_to_flat_v2'
+; CHECK-LABEL: 'addrspacecast_local_to_flat_v2'
 ; CHECK: estimated cost of 2 for {{.*}} addrspacecast <2 x i8 addrspace(3)*> %ptr to <2 x i8*>
 define <2 x i8*> @addrspacecast_local_to_flat_v2(<2 x i8 addrspace(3)*> %ptr) #0 {
   %cast = addrspacecast <2 x i8 addrspace(3)*> %ptr to <2 x i8*>
   ret <2 x i8*> %cast
 }
 
-; CHECK: 'addrspacecast_local_to_flat_v32'
+; CHECK-LABEL: 'addrspacecast_local_to_flat_v32'
 ; CHECK: estimated cost of 32 for {{.*}} addrspacecast <32 x i8 addrspace(3)*> %ptr to <32 x i8*>
 define <32 x i8*> @addrspacecast_local_to_flat_v32(<32 x i8 addrspace(3)*> %ptr) #0 {
   %cast = addrspacecast <32 x i8 addrspace(3)*> %ptr to <32 x i8*>
   ret <32 x i8*> %cast
 }
 
+; CHECK-LABEL: 'addrspacecast_flat_to_local'
+; CHECK: estimated cost of 0 for {{.*}} addrspacecast i8* %ptr to i8 addrspace(3)*
+define i8 addrspace(3)* @addrspacecast_flat_to_local(i8* %ptr) #0 {
+  %cast = addrspacecast i8* %ptr to i8 addrspace(3)*
+  ret i8 addrspace(3)* %cast
+}
+
+; CHECK-LABEL: 'addrspacecast_flat_to_local_v2'
+; CHECK: estimated cost of 0 for {{.*}} addrspacecast <2 x i8*> %ptr to <2 x i8 addrspace(3)*>
+define <2 x i8 addrspace(3)*> @addrspacecast_flat_to_local_v2(<2 x i8*> %ptr) #0 {
+  %cast = addrspacecast <2 x i8*> %ptr to <2 x i8 addrspace(3)*>
+  ret <2 x i8 addrspace(3)*> %cast
+}
+
+; CHECK-LABEL: 'addrspacecast_flat_to_local_v32'
+; CHECK: estimated cost of 0 for {{.*}} addrspacecast <32 x i8*> %ptr to <32 x i8 addrspace(3)*>
+define <32 x i8 addrspace(3)*> @addrspacecast_flat_to_local_v32(<32 x i8*> %ptr) #0 {
+  %cast = addrspacecast <32 x i8*> %ptr to <32 x i8 addrspace(3)*>
+  ret <32 x i8 addrspace(3)*> %cast
+}
+
 attributes #0 = { nounwind readnone }
Index: test/Transforms/LoopUnroll/AMDGPU/unroll-cost-addrspacecast.ll
===================================================================
--- /dev/null
+++ test/Transforms/LoopUnroll/AMDGPU/unroll-cost-addrspacecast.ll
@@ -0,0 +1,77 @@
+; RUN: opt -S -mtriple=amdgcn-unknown-amdhsa -mcpu=hawaii -loop-unroll -unroll-threshold=75 -unroll-peel-count=0 -unroll-allow-partial=false -unroll-max-iteration-count-to-analyze=16 < %s | FileCheck %s
+
+; CHECK-LABEL: @test_func_addrspacecast_cost_noop(
+; CHECK-NOT: br i1
+define amdgpu_kernel void @test_func_addrspacecast_cost_noop(float addrspace(1)* noalias nocapture %out, float addrspace(1)* noalias nocapture %in) #0 {
+entry:
+  br label %for.body
+
+for.body:
+  %indvars.iv = phi i32 [ %indvars.iv.next, %for.body ], [ 0, %entry ]
+  %sum.02 = phi float [ %fmul, %for.body ], [ 0.0, %entry ]
+  %arrayidx.in = getelementptr inbounds float, float addrspace(1)* %in, i32 %indvars.iv
+  %arrayidx.out = getelementptr inbounds float, float addrspace(1)* %out, i32 %indvars.iv
+  %cast.in = addrspacecast float addrspace(1)* %arrayidx.in to float*
+  %cast.out = addrspacecast float addrspace(1)* %arrayidx.out to float*
+  %load = load float, float* %cast.in
+  %fmul = fmul float %load, %sum.02
+  store float %fmul, float* %cast.out
+  %indvars.iv.next = add i32 %indvars.iv, 1
+  %exitcond = icmp eq i32 %indvars.iv.next, 16
+  br i1 %exitcond, label %for.end, label %for.body
+
+for.end:
+  ret void
+}
+
+; Free, but not a no-op
+; CHECK-LABEL: @test_func_addrspacecast_cost_free(
+; CHECK-NOT: br i1
+define amdgpu_kernel void @test_func_addrspacecast_cost_free(float* noalias nocapture %out, float* noalias nocapture %in) #0 {
+entry:
+  br label %for.body
+
+for.body:
+  %indvars.iv = phi i32 [ %indvars.iv.next, %for.body ], [ 0, %entry ]
+  %sum.02 = phi float [ %fmul, %for.body ], [ 0.0, %entry ]
+  %arrayidx.in = getelementptr inbounds float, float* %in, i32 %indvars.iv
+  %arrayidx.out = getelementptr inbounds float, float* %out, i32 %indvars.iv
+  %cast.in = addrspacecast float* %arrayidx.in to float addrspace(3)*
+  %cast.out = addrspacecast float* %arrayidx.out to float addrspace(3)*
+  %load = load float, float addrspace(3)* %cast.in
+  %fmul = fmul float %load, %sum.02
+  store float %fmul, float addrspace(3)* %cast.out
+  %indvars.iv.next = add i32 %indvars.iv, 1
+  %exitcond = icmp eq i32 %indvars.iv.next, 16
+  br i1 %exitcond, label %for.end, label %for.body
+
+for.end:
+  ret void
+}
+
+; CHECK-LABEL: @test_func_addrspacecast_cost_nonfree(
+; CHECK: br i1 %exitcond
+define amdgpu_kernel void @test_func_addrspacecast_cost_nonfree(float addrspace(3)* noalias nocapture %out, float addrspace(3)* noalias nocapture %in) #0 {
+entry:
+  br label %for.body
+
+for.body:
+  %indvars.iv = phi i32 [ %indvars.iv.next, %for.body ], [ 0, %entry ]
+  %sum.02 = phi float [ %fmul, %for.body ], [ 0.0, %entry ]
+  %arrayidx.in = getelementptr inbounds float, float addrspace(3)* %in, i32 %indvars.iv
+  %arrayidx.out = getelementptr inbounds float, float addrspace(3)* %out, i32 %indvars.iv
+  %cast.in = addrspacecast float addrspace(3)* %arrayidx.in to float*
+  %cast.out = addrspacecast float addrspace(3)* %arrayidx.out to float*
+  %load = load float, float* %cast.in
+  %fmul = fmul float %load, %sum.02
+  store float %fmul, float* %cast.out
+  %indvars.iv.next = add i32 %indvars.iv, 1
+  %exitcond = icmp eq i32 %indvars.iv.next, 16
+  br i1 %exitcond, label %for.end, label %for.body
+
+for.end:
+  ret void
+}
+
+attributes #0 = { nounwind }
+attributes #1 = { nounwind readnone speculatable }