Index: lib/Target/AMDGPU/AMDGPULegalizerInfo.cpp
===================================================================
--- lib/Target/AMDGPU/AMDGPULegalizerInfo.cpp
+++ lib/Target/AMDGPU/AMDGPULegalizerInfo.cpp
@@ -539,11 +539,9 @@
         return std::make_pair(0, LLT::scalar(Query.Types[1].getSizeInBits()));
       });
 
-  if (ST.hasFlatAddressSpace()) {
-    getActionDefinitionsBuilder(G_ADDRSPACE_CAST)
-      .scalarize(0)
-      .custom();
-  }
+  getActionDefinitionsBuilder(G_ADDRSPACE_CAST)
+    .scalarize(0)
+    .custom();
 
   // TODO: Should load to s16 be legal? Most loads extend to 32-bits, but we
   // handle some operations by just promoting the register during
@@ -1106,6 +1104,7 @@
 
   MIRBuilder.setInstr(MI);
 
+  const LLT S32 = LLT::scalar(32);
   Register Dst = MI.getOperand(0).getReg();
   Register Src = MI.getOperand(1).getReg();
 
@@ -1127,6 +1126,26 @@
     return true;
   }
 
+  if (DestAS == AMDGPUAS::CONSTANT_ADDRESS_32BIT) {
+    // Truncate.
+    MIRBuilder.buildExtract(Dst, Src, 0);
+    MI.eraseFromParent();
+    return true;
+  }
+
+  if (SrcAS == AMDGPUAS::CONSTANT_ADDRESS_32BIT) {
+    // This is a simple zero extend.
+    //
+    // FIXME: This is a bit ugly due to creating a merge of 2 pointers to
+    // another. Merge operands are required to be the same type, but creating an
+    // extra ptrtoint would be kind of pointless.
+    auto Zero = MIRBuilder.buildConstant(
+      LLT::pointer(AMDGPUAS::CONSTANT_ADDRESS_32BIT, 32), 0);
+    MIRBuilder.buildMerge(Dst, {Src, Zero.getReg(0)});
+    MI.eraseFromParent();
+    return true;
+  }
+
   if (SrcAS == AMDGPUAS::FLAT_ADDRESS) {
     assert(DestAS == AMDGPUAS::LOCAL_ADDRESS ||
            DestAS == AMDGPUAS::PRIVATE_ADDRESS);
@@ -1148,8 +1167,11 @@
     return true;
   }
 
-  assert(SrcAS == AMDGPUAS::LOCAL_ADDRESS ||
-         SrcAS == AMDGPUAS::PRIVATE_ADDRESS);
+  if (SrcAS != AMDGPUAS::LOCAL_ADDRESS && SrcAS != AMDGPUAS::PRIVATE_ADDRESS)
+    return false;
+
+  if (!ST.hasFlatAddressSpace())
+    return false;
 
   auto SegmentNull =
       MIRBuilder.buildConstant(SrcTy, TM.getNullPointerValue(SrcAS));
@@ -1164,7 +1186,7 @@
   Register BuildPtr = MRI.createGenericVirtualRegister(DstTy);
 
   // Coerce the type of the low half of the result so we can use merge_values.
-  Register SrcAsInt = MRI.createGenericVirtualRegister(LLT::scalar(32));
+  Register SrcAsInt = MRI.createGenericVirtualRegister(S32);
   MIRBuilder.buildInstr(TargetOpcode::G_PTRTOINT)
     .addDef(SrcAsInt)
     .addUse(Src);
Index: test/CodeGen/AMDGPU/GlobalISel/legalize-addrspacecast.mir
===================================================================
--- test/CodeGen/AMDGPU/GlobalISel/legalize-addrspacecast.mir
+++ test/CodeGen/AMDGPU/GlobalISel/legalize-addrspacecast.mir
@@ -1,6 +1,7 @@
 # NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py
 # RUN: llc -march=amdgcn -mcpu=fiji -O0 -run-pass=legalizer -global-isel-abort=0 -o - %s  | FileCheck -check-prefix=VI %s
 # RUN: llc -march=amdgcn -mcpu=gfx900 -O0 -run-pass=legalizer -global-isel-abort=0 -o - %s  | FileCheck -check-prefix=GFX9 %s
+# RUN: llc -march=amdgcn -mcpu=tahiti -O0 -run-pass=legalizer -global-isel-abort=0 -o - %s  | FileCheck -check-prefix=SI %s
 
 ---
 name: test_addrspacecast_p0_to_p1
@@ -16,6 +17,10 @@
     ; GFX9: [[COPY:%[0-9]+]]:_(p0) = COPY $vgpr0_vgpr1
     ; GFX9: [[BITCAST:%[0-9]+]]:_(p1) = G_BITCAST [[COPY]](p0)
     ; GFX9: $vgpr0_vgpr1 = COPY [[BITCAST]](p1)
+    ; SI-LABEL: name: test_addrspacecast_p0_to_p1
+    ; SI: [[COPY:%[0-9]+]]:_(p0) = COPY $vgpr0_vgpr1
+    ; SI: [[BITCAST:%[0-9]+]]:_(p1) = G_BITCAST [[COPY]](p0)
+    ; SI: $vgpr0_vgpr1 = COPY [[BITCAST]](p1)
     %0:_(p0) = COPY $vgpr0_vgpr1
     %1:_(p1) = G_ADDRSPACE_CAST %0
     $vgpr0_vgpr1 = COPY %1
@@ -35,6 +40,10 @@
     ; GFX9: [[COPY:%[0-9]+]]:_(p1) = COPY $vgpr0_vgpr1
     ; GFX9: [[BITCAST:%[0-9]+]]:_(p0) = G_BITCAST [[COPY]](p1)
     ; GFX9: $vgpr0_vgpr1 = COPY [[BITCAST]](p0)
+    ; SI-LABEL: name: test_addrspacecast_p1_to_p0
+    ; SI: [[COPY:%[0-9]+]]:_(p1) = COPY $vgpr0_vgpr1
+    ; SI: [[BITCAST:%[0-9]+]]:_(p0) = G_BITCAST [[COPY]](p1)
+    ; SI: $vgpr0_vgpr1 = COPY [[BITCAST]](p0)
     %0:_(p1) = COPY $vgpr0_vgpr1
     %1:_(p0) = G_ADDRSPACE_CAST %0
     $vgpr0_vgpr1 = COPY %1
@@ -54,6 +63,10 @@
     ; GFX9: [[COPY:%[0-9]+]]:_(p0) = COPY $vgpr0_vgpr1
     ; GFX9: [[BITCAST:%[0-9]+]]:_(p4) = G_BITCAST [[COPY]](p0)
     ; GFX9: $vgpr0_vgpr1 = COPY [[BITCAST]](p4)
+    ; SI-LABEL: name: test_addrspacecast_p0_to_p4
+    ; SI: [[COPY:%[0-9]+]]:_(p0) = COPY $vgpr0_vgpr1
+    ; SI: [[BITCAST:%[0-9]+]]:_(p4) = G_BITCAST [[COPY]](p0)
+    ; SI: $vgpr0_vgpr1 = COPY [[BITCAST]](p4)
     %0:_(p0) = COPY $vgpr0_vgpr1
     %1:_(p4) = G_ADDRSPACE_CAST %0
     $vgpr0_vgpr1 = COPY %1
@@ -73,6 +86,10 @@
     ; GFX9: [[COPY:%[0-9]+]]:_(p4) = COPY $vgpr0_vgpr1
     ; GFX9: [[BITCAST:%[0-9]+]]:_(p0) = G_BITCAST [[COPY]](p4)
     ; GFX9: $vgpr0_vgpr1 = COPY [[BITCAST]](p0)
+    ; SI-LABEL: name: test_addrspacecast_p4_to_p0
+    ; SI: [[COPY:%[0-9]+]]:_(p4) = COPY $vgpr0_vgpr1
+    ; SI: [[BITCAST:%[0-9]+]]:_(p0) = G_BITCAST [[COPY]](p4)
+    ; SI: $vgpr0_vgpr1 = COPY [[BITCAST]](p0)
     %0:_(p4) = COPY $vgpr0_vgpr1
     %1:_(p0) = G_ADDRSPACE_CAST %0
     $vgpr0_vgpr1 = COPY %1
@@ -92,6 +109,10 @@
     ; GFX9: [[COPY:%[0-9]+]]:_(p0) = COPY $vgpr0_vgpr1
     ; GFX9: [[BITCAST:%[0-9]+]]:_(p999) = G_BITCAST [[COPY]](p0)
     ; GFX9: $vgpr0_vgpr1 = COPY [[BITCAST]](p999)
+    ; SI-LABEL: name: test_addrspacecast_p0_to_p999
+    ; SI: [[COPY:%[0-9]+]]:_(p0) = COPY $vgpr0_vgpr1
+    ; SI: [[BITCAST:%[0-9]+]]:_(p999) = G_BITCAST [[COPY]](p0)
+    ; SI: $vgpr0_vgpr1 = COPY [[BITCAST]](p999)
     %0:_(p0) = COPY $vgpr0_vgpr1
     %1:_(p999) = G_ADDRSPACE_CAST %0
     $vgpr0_vgpr1 = COPY %1
@@ -111,6 +132,10 @@
     ; GFX9: [[COPY:%[0-9]+]]:_(p999) = COPY $vgpr0_vgpr1
     ; GFX9: [[BITCAST:%[0-9]+]]:_(p0) = G_BITCAST [[COPY]](p999)
     ; GFX9: $vgpr0_vgpr1 = COPY [[BITCAST]](p0)
+    ; SI-LABEL: name: test_addrspacecast_p999_to_p0
+    ; SI: [[COPY:%[0-9]+]]:_(p999) = COPY $vgpr0_vgpr1
+    ; SI: [[BITCAST:%[0-9]+]]:_(p0) = G_BITCAST [[COPY]](p999)
+    ; SI: $vgpr0_vgpr1 = COPY [[BITCAST]](p0)
     %0:_(p999) = COPY $vgpr0_vgpr1
     %1:_(p0) = G_ADDRSPACE_CAST %0
     $vgpr0_vgpr1 = COPY %1
@@ -147,6 +172,10 @@
     ; GFX9: [[MV:%[0-9]+]]:_(p0) = G_MERGE_VALUES [[PTRTOINT]](s32), [[SHL]](s32)
     ; GFX9: [[SELECT:%[0-9]+]]:_(p0) = G_SELECT [[ICMP]](s1), [[MV]], [[C1]]
     ; GFX9: $vgpr0_vgpr1 = COPY [[SELECT]](p0)
+    ; SI-LABEL: name: test_addrspacecast_p5_to_p0
+    ; SI: [[COPY:%[0-9]+]]:_(p5) = COPY $vgpr0
+    ; SI: [[ADDRSPACE_CAST:%[0-9]+]]:_(p0) = G_ADDRSPACE_CAST [[COPY]](p5)
+    ; SI: $vgpr0_vgpr1 = COPY [[ADDRSPACE_CAST]](p0)
     %0:_(p5) = COPY $vgpr0
     %1:_(p0) = G_ADDRSPACE_CAST %0
     $vgpr0_vgpr1 = COPY %1
@@ -174,6 +203,14 @@
     ; GFX9: [[ICMP:%[0-9]+]]:_(s1) = G_ICMP intpred(ne), [[COPY]](p0), [[C1]]
     ; GFX9: [[SELECT:%[0-9]+]]:_(p5) = G_SELECT [[ICMP]](s1), [[EXTRACT]], [[C]]
     ; GFX9: $vgpr0 = COPY [[SELECT]](p5)
+    ; SI-LABEL: name: test_addrspacecast_p0_to_p5
+    ; SI: [[COPY:%[0-9]+]]:_(p0) = COPY $vgpr0_vgpr1
+    ; SI: [[C:%[0-9]+]]:_(p5) = G_CONSTANT i32 0
+    ; SI: [[C1:%[0-9]+]]:_(p0) = G_CONSTANT i64 0
+    ; SI: [[EXTRACT:%[0-9]+]]:_(p5) = G_EXTRACT [[COPY]](p0), 0
+    ; SI: [[ICMP:%[0-9]+]]:_(s1) = G_ICMP intpred(ne), [[COPY]](p0), [[C1]]
+    ; SI: [[SELECT:%[0-9]+]]:_(p5) = G_SELECT [[ICMP]](s1), [[EXTRACT]], [[C]]
+    ; SI: $vgpr0 = COPY [[SELECT]](p5)
     %0:_(p0) = COPY $vgpr0_vgpr1
     %1:_(p5) = G_ADDRSPACE_CAST %0
     $vgpr0 = COPY %1
@@ -210,6 +247,10 @@
     ; GFX9: [[MV:%[0-9]+]]:_(p0) = G_MERGE_VALUES [[PTRTOINT]](s32), [[SHL]](s32)
     ; GFX9: [[SELECT:%[0-9]+]]:_(p0) = G_SELECT [[ICMP]](s1), [[MV]], [[C1]]
     ; GFX9: $vgpr0_vgpr1 = COPY [[SELECT]](p0)
+    ; SI-LABEL: name: test_addrspacecast_p3_to_p0
+    ; SI: [[COPY:%[0-9]+]]:_(p3) = COPY $vgpr0
+    ; SI: [[ADDRSPACE_CAST:%[0-9]+]]:_(p0) = G_ADDRSPACE_CAST [[COPY]](p3)
+    ; SI: $vgpr0_vgpr1 = COPY [[ADDRSPACE_CAST]](p0)
     %0:_(p3) = COPY $vgpr0
     %1:_(p0) = G_ADDRSPACE_CAST %0
     $vgpr0_vgpr1 = COPY %1
@@ -237,6 +278,14 @@
     ; GFX9: [[ICMP:%[0-9]+]]:_(s1) = G_ICMP intpred(ne), [[COPY]](p0), [[C1]]
     ; GFX9: [[SELECT:%[0-9]+]]:_(p3) = G_SELECT [[ICMP]](s1), [[EXTRACT]], [[C]]
     ; GFX9: $vgpr0 = COPY [[SELECT]](p3)
+    ; SI-LABEL: name: test_addrspacecast_p0_to_p3
+    ; SI: [[COPY:%[0-9]+]]:_(p0) = COPY $vgpr0_vgpr1
+    ; SI: [[C:%[0-9]+]]:_(p3) = G_CONSTANT i32 -1
+    ; SI: [[C1:%[0-9]+]]:_(p0) = G_CONSTANT i64 0
+    ; SI: [[EXTRACT:%[0-9]+]]:_(p3) = G_EXTRACT [[COPY]](p0), 0
+    ; SI: [[ICMP:%[0-9]+]]:_(s1) = G_ICMP intpred(ne), [[COPY]](p0), [[C1]]
+    ; SI: [[SELECT:%[0-9]+]]:_(p3) = G_SELECT [[ICMP]](s1), [[EXTRACT]], [[C]]
+    ; SI: $vgpr0 = COPY [[SELECT]](p3)
     %0:_(p0) = COPY $vgpr0_vgpr1
     %1:_(p3) = G_ADDRSPACE_CAST %0
     $vgpr0 = COPY %1
@@ -262,6 +311,13 @@
     ; GFX9: [[BITCAST1:%[0-9]+]]:_(p1) = G_BITCAST [[UV1]](p0)
     ; GFX9: [[BUILD_VECTOR:%[0-9]+]]:_(<2 x p1>) = G_BUILD_VECTOR [[BITCAST]](p1), [[BITCAST1]](p1)
     ; GFX9: $vgpr0_vgpr1_vgpr2_vgpr3 = COPY [[BUILD_VECTOR]](<2 x p1>)
+    ; SI-LABEL: name: test_addrspacecast_v2p0_to_v2p1
+    ; SI: [[COPY:%[0-9]+]]:_(<2 x p0>) = COPY $vgpr0_vgpr1_vgpr2_vgpr3
+    ; SI: [[UV:%[0-9]+]]:_(p0), [[UV1:%[0-9]+]]:_(p0) = G_UNMERGE_VALUES [[COPY]](<2 x p0>)
+    ; SI: [[BITCAST:%[0-9]+]]:_(p1) = G_BITCAST [[UV]](p0)
+    ; SI: [[BITCAST1:%[0-9]+]]:_(p1) = G_BITCAST [[UV1]](p0)
+    ; SI: [[BUILD_VECTOR:%[0-9]+]]:_(<2 x p1>) = G_BUILD_VECTOR [[BITCAST]](p1), [[BITCAST1]](p1)
+    ; SI: $vgpr0_vgpr1_vgpr2_vgpr3 = COPY [[BUILD_VECTOR]](<2 x p1>)
     %0:_(<2 x p0>) = COPY $vgpr0_vgpr1_vgpr2_vgpr3
     %1:_(<2 x p1>) = G_ADDRSPACE_CAST %0
     $vgpr0_vgpr1_vgpr2_vgpr3 = COPY %1
@@ -287,6 +343,13 @@
     ; GFX9: [[BITCAST1:%[0-9]+]]:_(p0) = G_BITCAST [[UV1]](p1)
     ; GFX9: [[BUILD_VECTOR:%[0-9]+]]:_(<2 x p0>) = G_BUILD_VECTOR [[BITCAST]](p0), [[BITCAST1]](p0)
     ; GFX9: $vgpr0_vgpr1_vgpr2_vgpr3 = COPY [[BUILD_VECTOR]](<2 x p0>)
+    ; SI-LABEL: name: test_addrspacecast_v2p1_to_v2p0
+    ; SI: [[COPY:%[0-9]+]]:_(<2 x p1>) = COPY $vgpr0_vgpr1_vgpr2_vgpr3
+    ; SI: [[UV:%[0-9]+]]:_(p1), [[UV1:%[0-9]+]]:_(p1) = G_UNMERGE_VALUES [[COPY]](<2 x p1>)
+    ; SI: [[BITCAST:%[0-9]+]]:_(p0) = G_BITCAST [[UV]](p1)
+    ; SI: [[BITCAST1:%[0-9]+]]:_(p0) = G_BITCAST [[UV1]](p1)
+    ; SI: [[BUILD_VECTOR:%[0-9]+]]:_(<2 x p0>) = G_BUILD_VECTOR [[BITCAST]](p0), [[BITCAST1]](p0)
+    ; SI: $vgpr0_vgpr1_vgpr2_vgpr3 = COPY [[BUILD_VECTOR]](<2 x p0>)
     %0:_(<2 x p1>) = COPY $vgpr0_vgpr1_vgpr2_vgpr3
     %1:_(<2 x p0>) = G_ADDRSPACE_CAST %0
     $vgpr0_vgpr1_vgpr2_vgpr3 = COPY %1
@@ -324,6 +387,19 @@
     ; GFX9: [[SELECT1:%[0-9]+]]:_(p3) = G_SELECT [[ICMP1]](s1), [[EXTRACT1]], [[C]]
     ; GFX9: [[BUILD_VECTOR:%[0-9]+]]:_(<2 x p3>) = G_BUILD_VECTOR [[SELECT]](p3), [[SELECT1]](p3)
     ; GFX9: $vgpr0_vgpr1 = COPY [[BUILD_VECTOR]](<2 x p3>)
+    ; SI-LABEL: name: test_addrspacecast_v2p0_to_v2p3
+    ; SI: [[COPY:%[0-9]+]]:_(<2 x p0>) = COPY $vgpr0_vgpr1_vgpr2_vgpr3
+    ; SI: [[UV:%[0-9]+]]:_(p0), [[UV1:%[0-9]+]]:_(p0) = G_UNMERGE_VALUES [[COPY]](<2 x p0>)
+    ; SI: [[C:%[0-9]+]]:_(p3) = G_CONSTANT i32 -1
+    ; SI: [[C1:%[0-9]+]]:_(p0) = G_CONSTANT i64 0
+    ; SI: [[EXTRACT:%[0-9]+]]:_(p3) = G_EXTRACT [[UV]](p0), 0
+    ; SI: [[ICMP:%[0-9]+]]:_(s1) = G_ICMP intpred(ne), [[UV]](p0), [[C1]]
+    ; SI: [[SELECT:%[0-9]+]]:_(p3) = G_SELECT [[ICMP]](s1), [[EXTRACT]], [[C]]
+    ; SI: [[EXTRACT1:%[0-9]+]]:_(p3) = G_EXTRACT [[UV1]](p0), 0
+    ; SI: [[ICMP1:%[0-9]+]]:_(s1) = G_ICMP intpred(ne), [[UV1]](p0), [[C1]]
+    ; SI: [[SELECT1:%[0-9]+]]:_(p3) = G_SELECT [[ICMP1]](s1), [[EXTRACT1]], [[C]]
+    ; SI: [[BUILD_VECTOR:%[0-9]+]]:_(<2 x p3>) = G_BUILD_VECTOR [[SELECT]](p3), [[SELECT1]](p3)
+    ; SI: $vgpr0_vgpr1 = COPY [[BUILD_VECTOR]](<2 x p3>)
     %0:_(<2 x p0>) = COPY $vgpr0_vgpr1_vgpr2_vgpr3
     %1:_(<2 x p3>) = G_ADDRSPACE_CAST %0
     $vgpr0_vgpr1 = COPY %1
@@ -377,7 +453,112 @@
     ; GFX9: [[SELECT1:%[0-9]+]]:_(p0) = G_SELECT [[ICMP1]](s1), [[MV1]], [[C1]]
     ; GFX9: [[BUILD_VECTOR:%[0-9]+]]:_(<2 x p0>) = G_BUILD_VECTOR [[SELECT]](p0), [[SELECT1]](p0)
     ; GFX9: $vgpr0_vgpr1_vgpr2_vgpr3 = COPY [[BUILD_VECTOR]](<2 x p0>)
+    ; SI-LABEL: name: test_addrspacecast_v2p3_to_v2p0
+    ; SI: [[COPY:%[0-9]+]]:_(<2 x p3>) = COPY $vgpr0_vgpr1
+    ; SI: [[UV:%[0-9]+]]:_(p3), [[UV1:%[0-9]+]]:_(p3) = G_UNMERGE_VALUES [[COPY]](<2 x p3>)
+    ; SI: [[ADDRSPACE_CAST:%[0-9]+]]:_(p0) = G_ADDRSPACE_CAST [[UV]](p3)
+    ; SI: [[ADDRSPACE_CAST1:%[0-9]+]]:_(p0) = G_ADDRSPACE_CAST [[UV1]](p3)
+    ; SI: [[BUILD_VECTOR:%[0-9]+]]:_(<2 x p0>) = G_BUILD_VECTOR [[ADDRSPACE_CAST]](p0), [[ADDRSPACE_CAST1]](p0)
+    ; SI: $vgpr0_vgpr1_vgpr2_vgpr3 = COPY [[BUILD_VECTOR]](<2 x p0>)
     %0:_(<2 x p3>) = COPY $vgpr0_vgpr1
     %1:_(<2 x p0>) = G_ADDRSPACE_CAST %0
     $vgpr0_vgpr1_vgpr2_vgpr3 = COPY %1
 ...
+
+---
+name: test_addrspacecast_p4_to_p6
+body: |
+  bb.0:
+    liveins: $vgpr0_vgpr1
+
+    ; VI-LABEL: name: test_addrspacecast_p4_to_p6
+    ; VI: [[COPY:%[0-9]+]]:_(p4) = COPY $vgpr0_vgpr1
+    ; VI: [[EXTRACT:%[0-9]+]]:_(p6) = G_EXTRACT [[COPY]](p4), 0
+    ; VI: $vgpr0 = COPY [[EXTRACT]](p6)
+    ; GFX9-LABEL: name: test_addrspacecast_p4_to_p6
+    ; GFX9: [[COPY:%[0-9]+]]:_(p4) = COPY $vgpr0_vgpr1
+    ; GFX9: [[EXTRACT:%[0-9]+]]:_(p6) = G_EXTRACT [[COPY]](p4), 0
+    ; GFX9: $vgpr0 = COPY [[EXTRACT]](p6)
+    ; SI-LABEL: name: test_addrspacecast_p4_to_p6
+    ; SI: [[COPY:%[0-9]+]]:_(p4) = COPY $vgpr0_vgpr1
+    ; SI: [[EXTRACT:%[0-9]+]]:_(p6) = G_EXTRACT [[COPY]](p4), 0
+    ; SI: $vgpr0 = COPY [[EXTRACT]](p6)
+    %0:_(p4) = COPY $vgpr0_vgpr1
+    %1:_(p6) = G_ADDRSPACE_CAST %0
+    $vgpr0 = COPY %1
+...
+
+---
+name: test_addrspacecast_p6_to_p4
+body: |
+  bb.0:
+    liveins: $vgpr0
+
+    ; VI-LABEL: name: test_addrspacecast_p6_to_p4
+    ; VI: [[COPY:%[0-9]+]]:_(p6) = COPY $vgpr0
+    ; VI: [[C:%[0-9]+]]:_(p6) = G_CONSTANT i32 0
+    ; VI: [[MV:%[0-9]+]]:_(p4) = G_MERGE_VALUES [[COPY]](p6), [[C]](p6)
+    ; VI: $vgpr0_vgpr1 = COPY [[MV]](p4)
+    ; GFX9-LABEL: name: test_addrspacecast_p6_to_p4
+    ; GFX9: [[COPY:%[0-9]+]]:_(p6) = COPY $vgpr0
+    ; GFX9: [[C:%[0-9]+]]:_(p6) = G_CONSTANT i32 0
+    ; GFX9: [[MV:%[0-9]+]]:_(p4) = G_MERGE_VALUES [[COPY]](p6), [[C]](p6)
+    ; GFX9: $vgpr0_vgpr1 = COPY [[MV]](p4)
+    ; SI-LABEL: name: test_addrspacecast_p6_to_p4
+    ; SI: [[COPY:%[0-9]+]]:_(p6) = COPY $vgpr0
+    ; SI: [[C:%[0-9]+]]:_(p6) = G_CONSTANT i32 0
+    ; SI: [[MV:%[0-9]+]]:_(p4) = G_MERGE_VALUES [[COPY]](p6), [[C]](p6)
+    ; SI: $vgpr0_vgpr1 = COPY [[MV]](p4)
+    %0:_(p6) = COPY $vgpr0
+    %1:_(p4) = G_ADDRSPACE_CAST %0
+    $vgpr0_vgpr1 = COPY %1
+...
+
+---
+name: test_addrspacecast_p0_to_p6
+body: |
+  bb.0:
+    liveins: $vgpr0_vgpr1
+
+    ; VI-LABEL: name: test_addrspacecast_p0_to_p6
+    ; VI: [[COPY:%[0-9]+]]:_(p0) = COPY $vgpr0_vgpr1
+    ; VI: [[EXTRACT:%[0-9]+]]:_(p6) = G_EXTRACT [[COPY]](p0), 0
+    ; VI: $vgpr0 = COPY [[EXTRACT]](p6)
+    ; GFX9-LABEL: name: test_addrspacecast_p0_to_p6
+    ; GFX9: [[COPY:%[0-9]+]]:_(p0) = COPY $vgpr0_vgpr1
+    ; GFX9: [[EXTRACT:%[0-9]+]]:_(p6) = G_EXTRACT [[COPY]](p0), 0
+    ; GFX9: $vgpr0 = COPY [[EXTRACT]](p6)
+    ; SI-LABEL: name: test_addrspacecast_p0_to_p6
+    ; SI: [[COPY:%[0-9]+]]:_(p0) = COPY $vgpr0_vgpr1
+    ; SI: [[EXTRACT:%[0-9]+]]:_(p6) = G_EXTRACT [[COPY]](p0), 0
+    ; SI: $vgpr0 = COPY [[EXTRACT]](p6)
+    %0:_(p0) = COPY $vgpr0_vgpr1
+    %1:_(p6) = G_ADDRSPACE_CAST %0
+    $vgpr0 = COPY %1
+...
+
+---
+name: test_addrspacecast_p6_to_p0
+body: |
+  bb.0:
+    liveins: $vgpr0
+
+    ; VI-LABEL: name: test_addrspacecast_p6_to_p0
+    ; VI: [[COPY:%[0-9]+]]:_(p6) = COPY $vgpr0
+    ; VI: [[C:%[0-9]+]]:_(p6) = G_CONSTANT i32 0
+    ; VI: [[MV:%[0-9]+]]:_(p0) = G_MERGE_VALUES [[COPY]](p6), [[C]](p6)
+    ; VI: $vgpr0_vgpr1 = COPY [[MV]](p0)
+    ; GFX9-LABEL: name: test_addrspacecast_p6_to_p0
+    ; GFX9: [[COPY:%[0-9]+]]:_(p6) = COPY $vgpr0
+    ; GFX9: [[C:%[0-9]+]]:_(p6) = G_CONSTANT i32 0
+    ; GFX9: [[MV:%[0-9]+]]:_(p0) = G_MERGE_VALUES [[COPY]](p6), [[C]](p6)
+    ; GFX9: $vgpr0_vgpr1 = COPY [[MV]](p0)
+    ; SI-LABEL: name: test_addrspacecast_p6_to_p0
+    ; SI: [[COPY:%[0-9]+]]:_(p6) = COPY $vgpr0
+    ; SI: [[C:%[0-9]+]]:_(p6) = G_CONSTANT i32 0
+    ; SI: [[MV:%[0-9]+]]:_(p0) = G_MERGE_VALUES [[COPY]](p6), [[C]](p6)
+    ; SI: $vgpr0_vgpr1 = COPY [[MV]](p0)
+    %0:_(p6) = COPY $vgpr0
+    %1:_(p0) = G_ADDRSPACE_CAST %0
+    $vgpr0_vgpr1 = COPY %1
+...