[AMDGPU] fix commuted case of sub combine

Differential Revision: https://reviews.llvm.org/D58481

llvm-svn: 354543

1 files changed, 28 insertions, 0 deletions

diff --git a/llvm/test/CodeGen/AMDGPU/combine-cond-add-sub.ll b/llvm/test/CodeGen/AMDGPU/combine-cond-add-sub.ll
index 5b3ad15fb1a..ae30ad37c37 100644
--- a/llvm/test/CodeGen/AMDGPU/combine-cond-add-sub.ll
+++ b/llvm/test/CodeGen/AMDGPU/combine-cond-add-sub.ll
@@ -127,6 +127,34 @@ bb:
   ret void
 }
 
+; GCN-LABEL: {{^}}sub_sube_commuted:
+; GCN-DAG: v_cmp_gt_u32_e{{32|64}} [[CC:[^,]+]], v{{[0-9]+}}, v{{[0-9]+}}
+; GCN-DAG: buffer_load_dword [[V:v[0-9]+]],
+; GCN:     v_subbrev_u32_e{{32|64}} [[SUBB:v[0-9]+]], {{[^,]+}}, 0, [[V]], [[CC]]
+; GCN:     v_sub_i32_e32 [[SUB:v[0-9]+]], vcc, s{{[0-9]+}}, [[SUBB]]
+; GCN:     v_add_i32_e32 {{.*}}, 0x64, [[SUB]]
+
+; GFX9-LABEL: {{^}}sub_sube_commuted:
+; GFX9-DAG: v_cmp_gt_u32_e{{32|64}} [[CC:[^,]+]], v{{[0-9]+}}, v{{[0-9]+}}
+; GFX9-DAG: global_load_dword [[V:v[0-9]+]],
+; GFX9:     v_subbrev_co_u32_e{{32|64}} [[SUBB:v[0-9]+]], {{[^,]+}}, 0, [[V]], [[CC]]
+; GFX9:     v_sub_u32_e32 [[SUB:v[0-9]+]], s{{[0-9]+}}, [[SUBB]]
+; GFX9:     v_add_u32_e32 {{.*}}, 0x64, [[SUB]]
+define amdgpu_kernel void @sub_sube_commuted(i32 addrspace(1)* nocapture %arg, i32 %a) {
+bb:
+  %x = tail call i32 @llvm.amdgcn.workitem.id.x()
+  %y = tail call i32 @llvm.amdgcn.workitem.id.y()
+  %gep = getelementptr inbounds i32, i32 addrspace(1)* %arg, i32 %x
+  %v = load i32, i32 addrspace(1)* %gep, align 4
+  %cmp = icmp ugt i32 %x, %y
+  %ext = sext i1 %cmp to i32
+  %adde = add i32 %v, %ext
+  %sub = sub i32 %adde, %a
+  %sub2 = sub i32 100, %sub
+  store i32 %sub2, i32 addrspace(1)* %gep, align 4
+  ret void
+}
+
 ; GCN-LABEL: {{^}}sube_sub:
 ; GCN: v_cmp_gt_u32_e{{32|64}} [[CC:[^,]+]], v{{[0-9]+}}, v{{[0-9]+}}
 ; GCN: v_subb_u32_e{{32|64}} v{{[0-9]+}}, {{[^,]+}}, v{{[0-9]+}}, v{{[0-9]+}}, [[CC]]