llvm/test/Transforms/GVNSink/struct.ll

; RUN: opt -gvn-sink -S < %s | FileCheck %s
; RUN: opt -passes=gvn-sink -S < %s | FileCheck %s

%struct = type {i32, i32}
%struct2 = type { [ 2 x i32], i32 }

; Struct indices cannot be variant.

; CHECK-LABEL: @f() {
; CHECK: getelementptr
; CHECK: getelementptr
define void @f() {
bb:
  br i1 undef, label %bb2, label %bb1

bb1:                                              ; preds = %bb
  %tmp = getelementptr inbounds %struct, %struct* null, i64 0, i32 1
  br label %bb4

bb2:                                              ; preds = %bb
  %tmp3 = getelementptr inbounds %struct, %struct* null, i64 0, i32 0
  br label %bb4

bb4:                                              ; preds = %bb2, %bb1
  %tmp5 = phi i32 [ 1, %bb1 ], [ 0, %bb2 ]
  ret void
}

; Struct indices cannot be variant.

; CHECK-LABEL: @g() {
; CHECK: getelementptr
; CHECK: getelementptr
define void @g() {
bb:
  br i1 undef, label %bb2, label %bb1

bb1:                                              ; preds = %bb
  %tmp = getelementptr inbounds %struct2, %struct2* null, i64 0, i32 0, i32 1
  br label %bb4

bb2:                                              ; preds = %bb
  %tmp3 = getelementptr inbounds %struct2, %struct2* null, i64 0, i32 0, i32 0
  br label %bb4

bb4:                                              ; preds = %bb2, %bb1
  %tmp5 = phi i32 [ 1, %bb1 ], [ 0, %bb2 ]
  ret void
}


; ... but the first parameter to a GEP can.

; CHECK-LABEL: @h() {
; CHECK: getelementptr
; CHECK-NOT: getelementptr
define void @h() {
bb:
  br i1 undef, label %bb2, label %bb1

bb1:                                              ; preds = %bb
  %tmp = getelementptr inbounds %struct, %struct* null, i32 0, i32 0
  br label %bb4

bb2:                                              ; preds = %bb
  %tmp3 = getelementptr inbounds %struct, %struct* null, i32 1, i32 0
  br label %bb4

bb4:                                              ; preds = %bb2, %bb1
  %tmp5 = phi i32 [ 0, %bb1 ], [ 1, %bb2 ]
  ret void
}