Index: llvm/trunk/lib/Target/AMDGPU/SILoadStoreOptimizer.cpp
===================================================================
--- llvm/trunk/lib/Target/AMDGPU/SILoadStoreOptimizer.cpp
+++ llvm/trunk/lib/Target/AMDGPU/SILoadStoreOptimizer.cpp
@@ -226,6 +226,15 @@
     Opc = (EltSize == 4) ? AMDGPU::DS_READ2ST64_B32 : AMDGPU::DS_READ2ST64_B64;
   }
 
+  unsigned SubRegIdx0 = (EltSize == 4) ? AMDGPU::sub0 : AMDGPU::sub0_sub1;
+  unsigned SubRegIdx1 = (EltSize == 4) ? AMDGPU::sub1 : AMDGPU::sub2_sub3;
+
+  if (NewOffset0 > NewOffset1) {
+    // Canonicalize the merged instruction so the smaller offset comes first.
+    std::swap(NewOffset0, NewOffset1);
+    std::swap(SubRegIdx0, SubRegIdx1);
+  }
+
   assert((isUInt<8>(NewOffset0) && isUInt<8>(NewOffset1)) &&
          (NewOffset0 != NewOffset1) &&
          "Computed offset doesn't fit");
@@ -246,9 +255,6 @@
     .addMemOperand(*I->memoperands_begin())
     .addMemOperand(*Paired->memoperands_begin());
 
-  unsigned SubRegIdx0 = (EltSize == 4) ? AMDGPU::sub0 : AMDGPU::sub0_sub1;
-  unsigned SubRegIdx1 = (EltSize == 4) ? AMDGPU::sub1 : AMDGPU::sub2_sub3;
-
   const MCInstrDesc &CopyDesc = TII->get(TargetOpcode::COPY);
 
   // Copy to the old destination registers.
@@ -322,6 +328,12 @@
     Opc = (EltSize == 4) ? AMDGPU::DS_WRITE2ST64_B32 : AMDGPU::DS_WRITE2ST64_B64;
   }
 
+  if (NewOffset0 > NewOffset1) {
+    // Canonicalize the merged instruction so the smaller offset comes first.
+    std::swap(NewOffset0, NewOffset1);
+    std::swap(Data0, Data1);
+  }
+
   assert((isUInt<8>(NewOffset0) && isUInt<8>(NewOffset1)) &&
          (NewOffset0 != NewOffset1) &&
          "Computed offset doesn't fit");
Index: llvm/trunk/test/CodeGen/AMDGPU/ds_read2_offset_order.ll
===================================================================
--- llvm/trunk/test/CodeGen/AMDGPU/ds_read2_offset_order.ll
+++ llvm/trunk/test/CodeGen/AMDGPU/ds_read2_offset_order.ll
@@ -9,7 +9,7 @@
 ; SI-LABEL: {{^}}offset_order:
 
 ; SI: ds_read2_b32 v[{{[0-9]+}}:{{[0-9]+}}], v{{[0-9]+}} offset0:2 offset1:3
-; SI: ds_read2_b32 v[{{[0-9]+}}:{{[0-9]+}}], v{{[0-9]+}} offset0:14 offset1:12
+; SI: ds_read2_b32 v[{{[0-9]+}}:{{[0-9]+}}], v{{[0-9]+}} offset0:12 offset1:14
 ; SI: ds_read_b32 v{{[0-9]+}}, v{{[0-9]+}} offset:44
 
 define void @offset_order(float addrspace(1)* %out) {
Index: llvm/trunk/test/CodeGen/AMDGPU/ds_read2st64.ll
===================================================================
--- llvm/trunk/test/CodeGen/AMDGPU/ds_read2st64.ll
+++ llvm/trunk/test/CodeGen/AMDGPU/ds_read2st64.ll
@@ -44,9 +44,9 @@
 }
 
 ; SI-LABEL: @simple_read2st64_f32_max_offset
-; SI: ds_read2st64_b32 v{{\[}}[[LO_VREG:[0-9]+]]:[[HI_VREG:[0-9]+]]{{\]}}, v{{[0-9]+}} offset0:255 offset1:1
+; SI: ds_read2st64_b32 v{{\[}}[[LO_VREG:[0-9]+]]:[[HI_VREG:[0-9]+]]{{\]}}, v{{[0-9]+}} offset0:1 offset1:255
 ; SI: s_waitcnt lgkmcnt(0)
-; SI: v_add_f32_e32 [[RESULT:v[0-9]+]], v[[LO_VREG]], v[[HI_VREG]]
+; SI: v_add_f32_e32 [[RESULT:v[0-9]+]], v[[HI_VREG]], v[[LO_VREG]]
 ; SI: buffer_store_dword [[RESULT]]
 ; SI: s_endpgm
 define void @simple_read2st64_f32_max_offset(float addrspace(1)* %out, float addrspace(3)* %lds) #0 {
@@ -176,9 +176,9 @@
 
 ; The maximum is not the usual 0xff because 0xff * 8 * 64 > 0xffff
 ; SI-LABEL: @simple_read2st64_f64_max_offset
-; SI: ds_read2st64_b64 v{{\[}}[[LO_VREG:[0-9]+]]:[[HI_VREG:[0-9]+]]{{\]}}, v{{[0-9]+}} offset0:127 offset1:4
+; SI: ds_read2st64_b64 v{{\[}}[[LO_VREG:[0-9]+]]:[[HI_VREG:[0-9]+]]{{\]}}, v{{[0-9]+}} offset0:4 offset1:127
 ; SI: s_waitcnt lgkmcnt(0)
-; SI: v_add_f64 [[RESULT:v\[[0-9]+:[0-9]+\]]], v{{\[[0-9]+}}:[[HI_VREG]]{{\]}}, v{{\[}}[[LO_VREG]]:{{[0-9]+\]}}
+; SI: v_add_f64 [[RESULT:v\[[0-9]+:[0-9]+\]]], v{{\[}}[[LO_VREG]]:{{[0-9]+\]}}, v{{\[[0-9]+}}:[[HI_VREG]]{{\]}}
 ; SI: buffer_store_dwordx2 [[RESULT]]
 ; SI: s_endpgm
 define void @simple_read2st64_f64_max_offset(double addrspace(1)* %out, double addrspace(3)* %lds) #0 {
Index: llvm/trunk/test/CodeGen/AMDGPU/load-local-i16.ll
===================================================================
--- llvm/trunk/test/CodeGen/AMDGPU/load-local-i16.ll
+++ llvm/trunk/test/CodeGen/AMDGPU/load-local-i16.ll
@@ -51,7 +51,7 @@
 }
 
 ; FUNC-LABEL: {{^}}local_load_v8i16:
-; GCN: ds_read2_b64 v{{\[[0-9]+:[0-9]+\]}}, v{{[0-9]+}} offset0:1{{$}}
+; GCN: ds_read2_b64 v{{\[[0-9]+:[0-9]+\]}}, v{{[0-9]+}} offset1:1{{$}}
 
 ; EG: LDS_READ_RET
 ; EG: LDS_READ_RET
@@ -65,8 +65,8 @@
 }
 
 ; FUNC-LABEL: {{^}}local_load_v16i16:
-; GCN-DAG: ds_read2_b64 v{{\[[0-9]+:[0-9]+\]}}, v{{[0-9]+}} offset0:3 offset1:2{{$}}
-; GCN-DAG: ds_read2_b64 v{{\[[0-9]+:[0-9]+\]}}, v{{[0-9]+}} offset0:1{{$}}
+; GCN-DAG: ds_read2_b64 v{{\[[0-9]+:[0-9]+\]}}, v{{[0-9]+}} offset0:2 offset1:3{{$}}
+; GCN-DAG: ds_read2_b64 v{{\[[0-9]+:[0-9]+\]}}, v{{[0-9]+}} offset1:1{{$}}
 
 
 ; EG: LDS_READ_RET
@@ -256,7 +256,7 @@
 
 ; FUNC-LABEL: {{^}}local_sextload_v16i16_to_v16i32:
 ; GCN-DAG: ds_read_b64 v{{\[[0-9]+:[0-9]+\]}}, v{{[0-9]+$}}
-; GCN-DAG: ds_read2_b64 v{{\[[0-9]+:[0-9]+\]}}, v{{[0-9]+}} offset0:3 offset1:1{{$}}
+; GCN-DAG: ds_read2_b64 v{{\[[0-9]+:[0-9]+\]}}, v{{[0-9]+}} offset0:1 offset1:3{{$}}
 ; GCN-DAG: ds_read_b64 v{{\[[0-9]+:[0-9]+\]}}, v{{[0-9]+}} offset:16{{$}}
 define void @local_sextload_v16i16_to_v16i32(<16 x i32> addrspace(3)* %out, <16 x i16> addrspace(3)* %in) #0 {
   %load = load <16 x i16>, <16 x i16> addrspace(3)* %in
@@ -280,7 +280,7 @@
 ; FUNC-LABEL: {{^}}local_sextload_v32i16_to_v32i32:
 ; GCN-DAG: ds_read2_b64 v{{\[[0-9]+:[0-9]+\]}}, v{{[0-9]+}} offset0:1 offset1:2{{$}}
 ; GCN-DAG: ds_read2_b64 v{{\[[0-9]+:[0-9]+\]}}, v{{[0-9]+}} offset0:3 offset1:4
-; GCN-DAG: ds_read2_b64 v{{\[[0-9]+:[0-9]+\]}}, v{{[0-9]+}} offset0:5{{$}}
+; GCN-DAG: ds_read2_b64 v{{\[[0-9]+:[0-9]+\]}}, v{{[0-9]+}} offset1:5{{$}}
 ; GCN-DAG: ds_read2_b64 v{{\[[0-9]+:[0-9]+\]}}, v{{[0-9]+}} offset0:6 offset1:7
 define void @local_sextload_v32i16_to_v32i32(<32 x i32> addrspace(3)* %out, <32 x i16> addrspace(3)* %in) #0 {
   %load = load <32 x i16>, <32 x i16> addrspace(3)* %in
Index: llvm/trunk/test/CodeGen/AMDGPU/load-local-i32.ll
===================================================================
--- llvm/trunk/test/CodeGen/AMDGPU/load-local-i32.ll
+++ llvm/trunk/test/CodeGen/AMDGPU/load-local-i32.ll
@@ -36,7 +36,7 @@
 }
 
 ; FUNC-LABEL: {{^}}local_load_v4i32:
-; GCN: ds_read2_b64 v{{\[[0-9]+:[0-9]+\]}}, v{{[0-9]+}} offset0:1{{$}}
+; GCN: ds_read2_b64 v{{\[[0-9]+:[0-9]+\]}}, v{{[0-9]+}} offset1:1{{$}}
 
 define void @local_load_v4i32(<4 x i32> addrspace(3)* %out, <4 x i32> addrspace(3)* %in) #0 {
 entry:
@@ -46,8 +46,8 @@
 }
 
 ; FUNC-LABEL: {{^}}local_load_v8i32:
-; GCN-DAG: ds_read2_b64 v{{\[[0-9]+:[0-9]+\]}}, v{{[0-9]+}} offset0:3 offset1:2{{$}}
-; GCN-DAG: ds_read2_b64 v{{\[[0-9]+:[0-9]+\]}}, v{{[0-9]+}} offset0:1{{$}}
+; GCN-DAG: ds_read2_b64 v{{\[[0-9]+:[0-9]+\]}}, v{{[0-9]+}} offset0:2 offset1:3{{$}}
+; GCN-DAG: ds_read2_b64 v{{\[[0-9]+:[0-9]+\]}}, v{{[0-9]+}} offset1:1{{$}}
 define void @local_load_v8i32(<8 x i32> addrspace(3)* %out, <8 x i32> addrspace(3)* %in) #0 {
 entry:
   %ld = load <8 x i32>, <8 x i32> addrspace(3)* %in
@@ -58,7 +58,7 @@
 ; FUNC-LABEL: {{^}}local_load_v16i32:
 ; GCN-DAG: ds_read2_b64 v{{\[[0-9]+:[0-9]+\]}}, v{{[0-9]+}} offset0:3 offset1:4{{$}}
 ; GCN-DAG: ds_read2_b64 v{{\[[0-9]+:[0-9]+\]}}, v{{[0-9]+}} offset0:5 offset1:6{{$}}
-; GCN-DAG: ds_read2_b64 v{{\[[0-9]+:[0-9]+\]}}, v{{[0-9]+}} offset0:7{{$}}
+; GCN-DAG: ds_read2_b64 v{{\[[0-9]+:[0-9]+\]}}, v{{[0-9]+}} offset1:7{{$}}
 ; GCN-DAG: ds_read2_b64 v{{\[[0-9]+:[0-9]+\]}}, v{{[0-9]+}} offset0:1 offset1:2{{$}}
 define void @local_load_v16i32(<16 x i32> addrspace(3)* %out, <16 x i32> addrspace(3)* %in) #0 {
 entry:
Index: llvm/trunk/test/CodeGen/AMDGPU/load-local-i8.ll
===================================================================
--- llvm/trunk/test/CodeGen/AMDGPU/load-local-i8.ll
+++ llvm/trunk/test/CodeGen/AMDGPU/load-local-i8.ll
@@ -64,8 +64,8 @@
 }
 
 ; FUNC-LABEL: {{^}}local_load_v16i8:
-; GCN: ds_read2_b64  v{{\[}}[[LO:[0-9]+]]:[[HI:[0-9]+]]{{\]}}, v{{[0-9]+}} offset0:1{{$}}
-; GCN: ds_write2_b64 v{{[0-9]+}}, v{{\[}}[[LO]]:{{[0-9]+}}], v[{{[0-9]+}}:[[HI]]{{\]}} offset0:1{{$}}
+; GCN: ds_read2_b64  v{{\[}}[[LO:[0-9]+]]:[[HI:[0-9]+]]{{\]}}, v{{[0-9]+}} offset1:1{{$}}
+; GCN: ds_write2_b64 v{{[0-9]+}}, v{{\[}}[[LO]]:{{[0-9]+}}], v[{{[0-9]+}}:[[HI]]{{\]}} offset1:1{{$}}
 
 ; EG: LDS_READ_RET
 ; EG: LDS_READ_RET
Index: llvm/trunk/test/CodeGen/AMDGPU/local-64.ll
===================================================================
--- llvm/trunk/test/CodeGen/AMDGPU/local-64.ll
+++ llvm/trunk/test/CodeGen/AMDGPU/local-64.ll
@@ -122,7 +122,7 @@
 
 ; BOTH-LABEL: {{^}}local_v2i64_store:
 ; BOTH-NOT: ADD
-; BOTH: ds_write2_b64 v{{[0-9]+}}, {{v\[[0-9]+:[0-9]+\]}}, {{v\[[0-9]+:[0-9]+\]}} offset0:15 offset1:14
+; BOTH: ds_write2_b64 v{{[0-9]+}}, {{v\[[0-9]+:[0-9]+\]}}, {{v\[[0-9]+:[0-9]+\]}} offset0:14 offset1:15
 ; BOTH: s_endpgm
 define void @local_v2i64_store(<2 x i64> addrspace(3)* %out) nounwind {
   %gep = getelementptr <2 x i64>, <2 x i64> addrspace(3)* %out, i32 7
@@ -132,7 +132,7 @@
 
 ; BOTH-LABEL: {{^}}local_v2i64_store_0_offset:
 ; BOTH-NOT: ADD
-; BOTH: ds_write2_b64 v{{[0-9]+}}, {{v\[[0-9]+:[0-9]+\]}}, {{v\[[0-9]+:[0-9]+\]}} offset0:1
+; BOTH: ds_write2_b64 v{{[0-9]+}}, {{v\[[0-9]+:[0-9]+\]}}, {{v\[[0-9]+:[0-9]+\]}} offset1:1
 ; BOTH: s_endpgm
 define void @local_v2i64_store_0_offset(<2 x i64> addrspace(3)* %out) nounwind {
   store <2 x i64> <i64 1234, i64 1234>, <2 x i64> addrspace(3)* %out, align 16
@@ -141,8 +141,8 @@
 
 ; BOTH-LABEL: {{^}}local_v4i64_store:
 ; BOTH-NOT: ADD
-; BOTH-DAG: ds_write2_b64 v{{[0-9]+}}, {{v\[[0-9]+:[0-9]+\]}}, {{v\[[0-9]+:[0-9]+\]}} offset0:31 offset1:30
-; BOTH-DAG: ds_write2_b64 v{{[0-9]+}}, {{v\[[0-9]+:[0-9]+\]}}, {{v\[[0-9]+:[0-9]+\]}} offset0:29 offset1:28
+; BOTH-DAG: ds_write2_b64 v{{[0-9]+}}, {{v\[[0-9]+:[0-9]+\]}}, {{v\[[0-9]+:[0-9]+\]}} offset0:30 offset1:31
+; BOTH-DAG: ds_write2_b64 v{{[0-9]+}}, {{v\[[0-9]+:[0-9]+\]}}, {{v\[[0-9]+:[0-9]+\]}} offset0:28 offset1:29
 ; BOTH: s_endpgm
 define void @local_v4i64_store(<4 x i64> addrspace(3)* %out) nounwind {
   %gep = getelementptr <4 x i64>, <4 x i64> addrspace(3)* %out, i32 7
@@ -152,8 +152,8 @@
 
 ; BOTH-LABEL: {{^}}local_v4i64_store_0_offset:
 ; BOTH-NOT: ADD
-; BOTH-DAG: ds_write2_b64 v{{[0-9]+}}, {{v\[[0-9]+:[0-9]+\]}}, {{v\[[0-9]+:[0-9]+\]}} offset0:3 offset1:2
-; BOTH-DAG: ds_write2_b64 v{{[0-9]+}}, {{v\[[0-9]+:[0-9]+\]}}, {{v\[[0-9]+:[0-9]+\]}} offset0:1
+; BOTH-DAG: ds_write2_b64 v{{[0-9]+}}, {{v\[[0-9]+:[0-9]+\]}}, {{v\[[0-9]+:[0-9]+\]}} offset0:2 offset1:3
+; BOTH-DAG: ds_write2_b64 v{{[0-9]+}}, {{v\[[0-9]+:[0-9]+\]}}, {{v\[[0-9]+:[0-9]+\]}} offset1:1
 ; BOTH: s_endpgm
 define void @local_v4i64_store_0_offset(<4 x i64> addrspace(3)* %out) nounwind {
   store <4 x i64> <i64 1234, i64 1234, i64 1234, i64 1234>, <4 x i64> addrspace(3)* %out, align 16