diff --git a/llvm/test/CodeGen/AMDGPU/GlobalISel/inst-select-store-flat.mir b/llvm/test/CodeGen/AMDGPU/GlobalISel/inst-select-store-flat.mir
--- a/llvm/test/CodeGen/AMDGPU/GlobalISel/inst-select-store-flat.mir
+++ b/llvm/test/CodeGen/AMDGPU/GlobalISel/inst-select-store-flat.mir
@@ -56,23 +56,23 @@
     ; GFX7: liveins: $vgpr0_vgpr1, $vgpr2
     ; GFX7: [[COPY:%[0-9]+]]:vreg_64 = COPY $vgpr0_vgpr1
     ; GFX7: [[COPY1:%[0-9]+]]:vgpr_32 = COPY $vgpr2
-    ; GFX7: FLAT_STORE_SHORT [[COPY]], [[COPY1]], 0, 0, 0, 0, implicit $exec, implicit $flat_scr :: (store 2)
+    ; GFX7: FLAT_STORE_DWORD [[COPY]], [[COPY1]], 0, 0, 0, 0, implicit $exec, implicit $flat_scr
     ; GFX8-LABEL: name: store_flat_s32_to_2
     ; GFX8: liveins: $vgpr0_vgpr1, $vgpr2
     ; GFX8: [[COPY:%[0-9]+]]:vreg_64 = COPY $vgpr0_vgpr1
     ; GFX8: [[COPY1:%[0-9]+]]:vgpr_32 = COPY $vgpr2
-    ; GFX8: FLAT_STORE_SHORT [[COPY]], [[COPY1]], 0, 0, 0, 0, implicit $exec, implicit $flat_scr :: (store 2)
+    ; GFX8: FLAT_STORE_DWORD [[COPY]], [[COPY1]], 0, 0, 0, 0, implicit $exec, implicit $flat_scr
     ; GFX9-LABEL: name: store_flat_s32_to_2
     ; GFX9: liveins: $vgpr0_vgpr1, $vgpr2
     ; GFX9: [[COPY:%[0-9]+]]:vreg_64 = COPY $vgpr0_vgpr1
     ; GFX9: [[COPY1:%[0-9]+]]:vgpr_32 = COPY $vgpr2
-    ; GFX9: FLAT_STORE_SHORT [[COPY]], [[COPY1]], 0, 0, 0, 0, implicit $exec, implicit $flat_scr :: (store 2)
+    ; GFX9: FLAT_STORE_DWORD [[COPY]], [[COPY1]], 0, 0, 0, 0, implicit $exec, implicit $flat_scr
     ; GFX10-LABEL: name: store_flat_s32_to_2
     ; GFX10: liveins: $vgpr0_vgpr1, $vgpr2
     ; GFX10: $vcc_hi = IMPLICIT_DEF
     ; GFX10: [[COPY:%[0-9]+]]:vreg_64 = COPY $vgpr0_vgpr1
     ; GFX10: [[COPY1:%[0-9]+]]:vgpr_32 = COPY $vgpr2
-    ; GFX10: FLAT_STORE_SHORT [[COPY]], [[COPY1]], 0, 0, 0, 0, implicit $exec, implicit $flat_scr :: (store 2)
+    ; GFX10: FLAT_STORE_DWORD [[COPY]], [[COPY1]], 0, 0, 0, 0, implicit $exec, implicit $flat_scr
     %0:vgpr(p1) = COPY $vgpr0_vgpr1
     %1:vgpr(s32) = COPY $vgpr2
     G_STORE %1, %0 :: (store 2, align 2, addrspace 0)
@@ -93,23 +93,23 @@
     ; GFX7: liveins: $vgpr0_vgpr1, $vgpr2
     ; GFX7: [[COPY:%[0-9]+]]:vreg_64 = COPY $vgpr0_vgpr1
     ; GFX7: [[COPY1:%[0-9]+]]:vgpr_32 = COPY $vgpr2
-    ; GFX7: FLAT_STORE_BYTE [[COPY]], [[COPY1]], 0, 0, 0, 0, implicit $exec, implicit $flat_scr :: (store 1)
+    ; GFX7: FLAT_STORE_DWORD [[COPY]], [[COPY1]], 0, 0, 0, 0, implicit $exec, implicit $flat_scr
     ; GFX8-LABEL: name: store_flat_s32_to_1
     ; GFX8: liveins: $vgpr0_vgpr1, $vgpr2
     ; GFX8: [[COPY:%[0-9]+]]:vreg_64 = COPY $vgpr0_vgpr1
     ; GFX8: [[COPY1:%[0-9]+]]:vgpr_32 = COPY $vgpr2
-    ; GFX8: FLAT_STORE_BYTE [[COPY]], [[COPY1]], 0, 0, 0, 0, implicit $exec, implicit $flat_scr :: (store 1)
+    ; GFX8: FLAT_STORE_DWORD [[COPY]], [[COPY1]], 0, 0, 0, 0, implicit $exec, implicit $flat_scr
     ; GFX9-LABEL: name: store_flat_s32_to_1
     ; GFX9: liveins: $vgpr0_vgpr1, $vgpr2
     ; GFX9: [[COPY:%[0-9]+]]:vreg_64 = COPY $vgpr0_vgpr1
     ; GFX9: [[COPY1:%[0-9]+]]:vgpr_32 = COPY $vgpr2
-    ; GFX9: FLAT_STORE_BYTE [[COPY]], [[COPY1]], 0, 0, 0, 0, implicit $exec, implicit $flat_scr :: (store 1)
+    ; GFX9: FLAT_STORE_DWORD [[COPY]], [[COPY1]], 0, 0, 0, 0, implicit $exec, implicit $flat_scr
     ; GFX10-LABEL: name: store_flat_s32_to_1
     ; GFX10: liveins: $vgpr0_vgpr1, $vgpr2
     ; GFX10: $vcc_hi = IMPLICIT_DEF
     ; GFX10: [[COPY:%[0-9]+]]:vreg_64 = COPY $vgpr0_vgpr1
     ; GFX10: [[COPY1:%[0-9]+]]:vgpr_32 = COPY $vgpr2
-    ; GFX10: FLAT_STORE_BYTE [[COPY]], [[COPY1]], 0, 0, 0, 0, implicit $exec, implicit $flat_scr :: (store 1)
+    ; GFX10: FLAT_STORE_DWORD [[COPY]], [[COPY1]], 0, 0, 0, 0, implicit $exec, implicit $flat_scr
     %0:vgpr(p1) = COPY $vgpr0_vgpr1
     %1:vgpr(s32) = COPY $vgpr2
     G_STORE %1, %0 :: (store 1, align 1, addrspace 0)
diff --git a/llvm/test/CodeGen/AMDGPU/GlobalISel/inst-select-store-global.mir b/llvm/test/CodeGen/AMDGPU/GlobalISel/inst-select-store-global.mir
--- a/llvm/test/CodeGen/AMDGPU/GlobalISel/inst-select-store-global.mir
+++ b/llvm/test/CodeGen/AMDGPU/GlobalISel/inst-select-store-global.mir
@@ -56,23 +56,23 @@
     ; GFX7: liveins: $vgpr0_vgpr1, $vgpr2
     ; GFX7: [[COPY:%[0-9]+]]:vreg_64 = COPY $vgpr0_vgpr1
     ; GFX7: [[COPY1:%[0-9]+]]:vgpr_32 = COPY $vgpr2
-    ; GFX7: FLAT_STORE_SHORT [[COPY]], [[COPY1]], 0, 0, 0, 0, implicit $exec, implicit $flat_scr :: (store 2, addrspace 1)
+    ; GFX7: FLAT_STORE_DWORD [[COPY]], [[COPY1]], 0, 0, 0, 0, implicit $exec, implicit $flat_scr
     ; GFX8-LABEL: name: store_global_s32_to_2
     ; GFX8: liveins: $vgpr0_vgpr1, $vgpr2
     ; GFX8: [[COPY:%[0-9]+]]:vreg_64 = COPY $vgpr0_vgpr1
     ; GFX8: [[COPY1:%[0-9]+]]:vgpr_32 = COPY $vgpr2
-    ; GFX8: FLAT_STORE_SHORT [[COPY]], [[COPY1]], 0, 0, 0, 0, implicit $exec, implicit $flat_scr :: (store 2, addrspace 1)
+    ; GFX8: FLAT_STORE_DWORD [[COPY]], [[COPY1]], 0, 0, 0, 0, implicit $exec, implicit $flat_scr
     ; GFX9-LABEL: name: store_global_s32_to_2
     ; GFX9: liveins: $vgpr0_vgpr1, $vgpr2
     ; GFX9: [[COPY:%[0-9]+]]:vreg_64 = COPY $vgpr0_vgpr1
     ; GFX9: [[COPY1:%[0-9]+]]:vgpr_32 = COPY $vgpr2
-    ; GFX9: GLOBAL_STORE_SHORT [[COPY]], [[COPY1]], 0, 0, 0, 0, implicit $exec :: (store 2, addrspace 1)
+    ; GFX9: FLAT_STORE_DWORD [[COPY]], [[COPY1]], 0, 0, 0, 0, implicit $exec, implicit $flat_scr
     ; GFX10-LABEL: name: store_global_s32_to_2
     ; GFX10: liveins: $vgpr0_vgpr1, $vgpr2
     ; GFX10: $vcc_hi = IMPLICIT_DEF
     ; GFX10: [[COPY:%[0-9]+]]:vreg_64 = COPY $vgpr0_vgpr1
     ; GFX10: [[COPY1:%[0-9]+]]:vgpr_32 = COPY $vgpr2
-    ; GFX10: GLOBAL_STORE_SHORT [[COPY]], [[COPY1]], 0, 0, 0, 0, implicit $exec :: (store 2, addrspace 1)
+    ; GFX10: FLAT_STORE_DWORD [[COPY]], [[COPY1]], 0, 0, 0, 0, implicit $exec, implicit $flat_scr
     %0:vgpr(p1) = COPY $vgpr0_vgpr1
     %1:vgpr(s32) = COPY $vgpr2
     G_STORE %1, %0 :: (store 2, align 2, addrspace 1)
@@ -93,23 +93,23 @@
     ; GFX7: liveins: $vgpr0_vgpr1, $vgpr2
     ; GFX7: [[COPY:%[0-9]+]]:vreg_64 = COPY $vgpr0_vgpr1
     ; GFX7: [[COPY1:%[0-9]+]]:vgpr_32 = COPY $vgpr2
-    ; GFX7: FLAT_STORE_BYTE [[COPY]], [[COPY1]], 0, 0, 0, 0, implicit $exec, implicit $flat_scr :: (store 1, addrspace 1)
+    ; GFX7: FLAT_STORE_DWORD [[COPY]], [[COPY1]], 0, 0, 0, 0, implicit $exec, implicit $flat_scr
     ; GFX8-LABEL: name: store_global_s32_to_1
     ; GFX8: liveins: $vgpr0_vgpr1, $vgpr2
     ; GFX8: [[COPY:%[0-9]+]]:vreg_64 = COPY $vgpr0_vgpr1
     ; GFX8: [[COPY1:%[0-9]+]]:vgpr_32 = COPY $vgpr2
-    ; GFX8: FLAT_STORE_BYTE [[COPY]], [[COPY1]], 0, 0, 0, 0, implicit $exec, implicit $flat_scr :: (store 1, addrspace 1)
+    ; GFX8: FLAT_STORE_DWORD [[COPY]], [[COPY1]], 0, 0, 0, 0, implicit $exec, implicit $flat_scr
     ; GFX9-LABEL: name: store_global_s32_to_1
     ; GFX9: liveins: $vgpr0_vgpr1, $vgpr2
     ; GFX9: [[COPY:%[0-9]+]]:vreg_64 = COPY $vgpr0_vgpr1
     ; GFX9: [[COPY1:%[0-9]+]]:vgpr_32 = COPY $vgpr2
-    ; GFX9: GLOBAL_STORE_BYTE [[COPY]], [[COPY1]], 0, 0, 0, 0, implicit $exec :: (store 1, addrspace 1)
+    ; GFX9: FLAT_STORE_DWORD [[COPY]], [[COPY1]], 0, 0, 0, 0, implicit $exec, implicit $flat_scr
     ; GFX10-LABEL: name: store_global_s32_to_1
     ; GFX10: liveins: $vgpr0_vgpr1, $vgpr2
     ; GFX10: $vcc_hi = IMPLICIT_DEF
     ; GFX10: [[COPY:%[0-9]+]]:vreg_64 = COPY $vgpr0_vgpr1
     ; GFX10: [[COPY1:%[0-9]+]]:vgpr_32 = COPY $vgpr2
-    ; GFX10: GLOBAL_STORE_BYTE [[COPY]], [[COPY1]], 0, 0, 0, 0, implicit $exec :: (store 1, addrspace 1)
+    ; GFX10: FLAT_STORE_DWORD [[COPY]], [[COPY1]], 0, 0, 0, 0, implicit $exec, implicit $flat_scr
     %0:vgpr(p1) = COPY $vgpr0_vgpr1
     %1:vgpr(s32) = COPY $vgpr2
     G_STORE %1, %0 :: (store 1, align 1, addrspace 1)
diff --git a/llvm/test/CodeGen/AMDGPU/GlobalISel/inst-select-store-private.mir b/llvm/test/CodeGen/AMDGPU/GlobalISel/inst-select-store-private.mir
--- a/llvm/test/CodeGen/AMDGPU/GlobalISel/inst-select-store-private.mir
+++ b/llvm/test/CodeGen/AMDGPU/GlobalISel/inst-select-store-private.mir
@@ -50,14 +50,14 @@
 
     ; GFX6-LABEL: name: store_private_s32_to_2
     ; GFX6: liveins: $vgpr0, $vgpr1
-    ; GFX6: [[COPY:%[0-9]+]]:vgpr_32 = COPY $vgpr0
-    ; GFX6: [[COPY1:%[0-9]+]]:vgpr_32 = COPY $vgpr1
-    ; GFX6: BUFFER_STORE_SHORT_OFFEN [[COPY]], [[COPY1]], $sgpr0_sgpr1_sgpr2_sgpr3, $sgpr4, 0, 0, 0, 0, 0, implicit $exec :: (store 2, addrspace 5)
+    ; GFX6: [[COPY:%[0-9]+]]:vgpr(s32) = COPY $vgpr0
+    ; GFX6: [[COPY1:%[0-9]+]]:vgpr(p5) = COPY $vgpr1
+    ; GFX6: G_STORE [[COPY]](s32), [[COPY1]](p5) :: (store 2, addrspace 5)
     ; GFX9-LABEL: name: store_private_s32_to_2
     ; GFX9: liveins: $vgpr0, $vgpr1
-    ; GFX9: [[COPY:%[0-9]+]]:vgpr_32 = COPY $vgpr0
-    ; GFX9: [[COPY1:%[0-9]+]]:vgpr_32 = COPY $vgpr1
-    ; GFX9: BUFFER_STORE_SHORT_OFFEN [[COPY]], [[COPY1]], $sgpr0_sgpr1_sgpr2_sgpr3, $sgpr4, 0, 0, 0, 0, 0, implicit $exec :: (store 2, addrspace 5)
+    ; GFX9: [[COPY:%[0-9]+]]:vgpr(s32) = COPY $vgpr0
+    ; GFX9: [[COPY1:%[0-9]+]]:vgpr(p5) = COPY $vgpr1
+    ; GFX9: G_STORE [[COPY]](s32), [[COPY1]](p5) :: (store 2, addrspace 5)
     %0:vgpr(s32) = COPY $vgpr0
     %1:vgpr(p5) = COPY $vgpr1
     G_STORE %0, %1 :: (store 2, align 2, addrspace 5)
@@ -81,14 +81,14 @@
 
     ; GFX6-LABEL: name: store_private_s32_to_1
     ; GFX6: liveins: $vgpr0, $vgpr1
-    ; GFX6: [[COPY:%[0-9]+]]:vgpr_32 = COPY $vgpr0
-    ; GFX6: [[COPY1:%[0-9]+]]:vgpr_32 = COPY $vgpr1
-    ; GFX6: BUFFER_STORE_BYTE_OFFEN [[COPY]], [[COPY1]], $sgpr0_sgpr1_sgpr2_sgpr3, $sgpr4, 0, 0, 0, 0, 0, implicit $exec :: (store 1, addrspace 5)
+    ; GFX6: [[COPY:%[0-9]+]]:vgpr(s32) = COPY $vgpr0
+    ; GFX6: [[COPY1:%[0-9]+]]:vgpr(p5) = COPY $vgpr1
+    ; GFX6: G_STORE [[COPY]](s32), [[COPY1]](p5) :: (store 1, addrspace 5)
     ; GFX9-LABEL: name: store_private_s32_to_1
     ; GFX9: liveins: $vgpr0, $vgpr1
-    ; GFX9: [[COPY:%[0-9]+]]:vgpr_32 = COPY $vgpr0
-    ; GFX9: [[COPY1:%[0-9]+]]:vgpr_32 = COPY $vgpr1
-    ; GFX9: BUFFER_STORE_BYTE_OFFEN [[COPY]], [[COPY1]], $sgpr0_sgpr1_sgpr2_sgpr3, $sgpr4, 0, 0, 0, 0, 0, implicit $exec :: (store 1, addrspace 5)
+    ; GFX9: [[COPY:%[0-9]+]]:vgpr(s32) = COPY $vgpr0
+    ; GFX9: [[COPY1:%[0-9]+]]:vgpr(p5) = COPY $vgpr1
+    ; GFX9: G_STORE [[COPY]](s32), [[COPY1]](p5) :: (store 1, addrspace 5)
     %0:vgpr(s32) = COPY $vgpr0
     %1:vgpr(p5) = COPY $vgpr1
     G_STORE %0, %1 :: (store 1, align 1, addrspace 5)
@@ -205,14 +205,17 @@
   bb.0:
 
     ; GFX6-LABEL: name: store_private_s32_to_1_fi_offset_4095
-    ; GFX6: [[V_MOV_B32_e32_:%[0-9]+]]:vgpr_32 = V_MOV_B32_e32 %stack.0, implicit $exec
-    ; GFX6: [[V_MOV_B32_e32_1:%[0-9]+]]:vgpr_32 = V_MOV_B32_e32 4095, implicit $exec
-    ; GFX6: %2:vgpr_32, dead %4:sreg_64_xexec = V_ADD_I32_e64 [[V_MOV_B32_e32_]], [[V_MOV_B32_e32_1]], 0, implicit $exec
-    ; GFX6: [[V_MOV_B32_e32_2:%[0-9]+]]:vgpr_32 = V_MOV_B32_e32 0, implicit $exec
-    ; GFX6: BUFFER_STORE_BYTE_OFFEN [[V_MOV_B32_e32_2]], %2, $sgpr0_sgpr1_sgpr2_sgpr3, $sgpr4, 0, 0, 0, 0, 0, implicit $exec :: (store 1, addrspace 5)
+    ; GFX6: [[FRAME_INDEX:%[0-9]+]]:vgpr(p5) = G_FRAME_INDEX %stack.0
+    ; GFX6: [[C:%[0-9]+]]:vgpr(s32) = G_CONSTANT i32 4095
+    ; GFX6: [[GEP:%[0-9]+]]:vgpr(p5) = G_GEP [[FRAME_INDEX]], [[C]](s32)
+    ; GFX6: [[C1:%[0-9]+]]:vgpr(s32) = G_CONSTANT i32 0
+    ; GFX6: G_STORE [[C1]](s32), [[GEP]](p5) :: (store 1, addrspace 5)
     ; GFX9-LABEL: name: store_private_s32_to_1_fi_offset_4095
-    ; GFX9: [[V_MOV_B32_e32_:%[0-9]+]]:vgpr_32 = V_MOV_B32_e32 0, implicit $exec
-    ; GFX9: BUFFER_STORE_BYTE_OFFEN [[V_MOV_B32_e32_]], %stack.0, $sgpr0_sgpr1_sgpr2_sgpr3, $sgpr32, 4095, 0, 0, 0, 0, implicit $exec :: (store 1, addrspace 5)
+    ; GFX9: [[FRAME_INDEX:%[0-9]+]]:vgpr(p5) = G_FRAME_INDEX %stack.0
+    ; GFX9: [[C:%[0-9]+]]:vgpr(s32) = G_CONSTANT i32 4095
+    ; GFX9: [[GEP:%[0-9]+]]:vgpr(p5) = G_GEP [[FRAME_INDEX]], [[C]](s32)
+    ; GFX9: [[C1:%[0-9]+]]:vgpr(s32) = G_CONSTANT i32 0
+    ; GFX9: G_STORE [[C1]](s32), [[GEP]](p5) :: (store 1, addrspace 5)
     %0:vgpr(p5) = G_FRAME_INDEX %stack.0
     %1:vgpr(s32) = G_CONSTANT i32 4095
     %2:vgpr(p5) = G_GEP %0, %1
@@ -238,11 +241,13 @@
   bb.0:
 
     ; GFX6-LABEL: name: store_private_s32_to_1_constant_4095
-    ; GFX6: [[V_MOV_B32_e32_:%[0-9]+]]:vgpr_32 = V_MOV_B32_e32 0, implicit $exec
-    ; GFX6: BUFFER_STORE_BYTE_OFFSET [[V_MOV_B32_e32_]], $sgpr0_sgpr1_sgpr2_sgpr3, $sgpr4, 4095, 0, 0, 0, 0, implicit $exec :: (store 1, addrspace 5)
+    ; GFX6: [[C:%[0-9]+]]:vgpr(p5) = G_CONSTANT i32 4095
+    ; GFX6: [[C1:%[0-9]+]]:vgpr(s32) = G_CONSTANT i32 0
+    ; GFX6: G_STORE [[C1]](s32), [[C]](p5) :: (store 1, addrspace 5)
     ; GFX9-LABEL: name: store_private_s32_to_1_constant_4095
-    ; GFX9: [[V_MOV_B32_e32_:%[0-9]+]]:vgpr_32 = V_MOV_B32_e32 0, implicit $exec
-    ; GFX9: BUFFER_STORE_BYTE_OFFSET [[V_MOV_B32_e32_]], $sgpr0_sgpr1_sgpr2_sgpr3, $sgpr4, 4095, 0, 0, 0, 0, implicit $exec :: (store 1, addrspace 5)
+    ; GFX9: [[C:%[0-9]+]]:vgpr(p5) = G_CONSTANT i32 4095
+    ; GFX9: [[C1:%[0-9]+]]:vgpr(s32) = G_CONSTANT i32 0
+    ; GFX9: G_STORE [[C1]](s32), [[C]](p5) :: (store 1, addrspace 5)
     %0:vgpr(p5) = G_CONSTANT i32 4095
     %1:vgpr(s32) = G_CONSTANT i32 0
     G_STORE %1, %0 :: (store 1, align 1, addrspace 5)
@@ -266,13 +271,13 @@
   bb.0:
 
     ; GFX6-LABEL: name: store_private_s32_to_1_constant_4096
-    ; GFX6: [[V_MOV_B32_e32_:%[0-9]+]]:vgpr_32 = V_MOV_B32_e32 0, implicit $exec
-    ; GFX6: [[V_MOV_B32_e32_1:%[0-9]+]]:vgpr_32 = V_MOV_B32_e32 4096, implicit $exec
-    ; GFX6: BUFFER_STORE_BYTE_OFFEN [[V_MOV_B32_e32_]], [[V_MOV_B32_e32_1]], $sgpr0_sgpr1_sgpr2_sgpr3, $sgpr4, 0, 0, 0, 0, 0, implicit $exec :: (store 1, addrspace 5)
+    ; GFX6: [[C:%[0-9]+]]:vgpr(p5) = G_CONSTANT i32 4096
+    ; GFX6: [[C1:%[0-9]+]]:vgpr(s32) = G_CONSTANT i32 0
+    ; GFX6: G_STORE [[C1]](s32), [[C]](p5) :: (store 1, addrspace 5)
     ; GFX9-LABEL: name: store_private_s32_to_1_constant_4096
-    ; GFX9: [[V_MOV_B32_e32_:%[0-9]+]]:vgpr_32 = V_MOV_B32_e32 0, implicit $exec
-    ; GFX9: [[V_MOV_B32_e32_1:%[0-9]+]]:vgpr_32 = V_MOV_B32_e32 4096, implicit $exec
-    ; GFX9: BUFFER_STORE_BYTE_OFFEN [[V_MOV_B32_e32_]], [[V_MOV_B32_e32_1]], $sgpr0_sgpr1_sgpr2_sgpr3, $sgpr4, 0, 0, 0, 0, 0, implicit $exec :: (store 1, addrspace 5)
+    ; GFX9: [[C:%[0-9]+]]:vgpr(p5) = G_CONSTANT i32 4096
+    ; GFX9: [[C1:%[0-9]+]]:vgpr(s32) = G_CONSTANT i32 0
+    ; GFX9: G_STORE [[C1]](s32), [[C]](p5) :: (store 1, addrspace 5)
     %0:vgpr(p5) = G_CONSTANT i32 4096
     %1:vgpr(s32) = G_CONSTANT i32 0
     G_STORE %1, %0 :: (store 1, align 1, addrspace 5)
diff --git a/llvm/utils/TableGen/GlobalISelEmitter.cpp b/llvm/utils/TableGen/GlobalISelEmitter.cpp
--- a/llvm/utils/TableGen/GlobalISelEmitter.cpp
+++ b/llvm/utils/TableGen/GlobalISelEmitter.cpp
@@ -3301,11 +3301,18 @@
       continue;
     }
 
-    if (Predicate.isStore() && Predicate.isTruncStore()) {
-      // FIXME: If MemoryVT is set, we end up with 2 checks for the MMO size.
-      InsnMatcher.addPredicate<MemoryVsLLTSizePredicateMatcher>(
-        0, MemoryVsLLTSizePredicateMatcher::LessThan, 0);
-      continue;
+    if (Predicate.isStore()) {
+      if (Predicate.isTruncStore()) {
+        // FIXME: If MemoryVT is set, we end up with 2 checks for the MMO size.
+        InsnMatcher.addPredicate<MemoryVsLLTSizePredicateMatcher>(
+            0, MemoryVsLLTSizePredicateMatcher::LessThan, 0);
+        continue;
+      } else {
+        // We need to check the sizes match here otherwise we could incorrectly
+        // match truncating stores with non-truncating ones.
+        InsnMatcher.addPredicate<MemoryVsLLTSizePredicateMatcher>(
+            0, MemoryVsLLTSizePredicateMatcher::EqualTo, 0);
+      }
     }
 
     // No check required. We already did it by swapping the opcode.