1; RUN: opt < %s -reassociate -instcombine -S | FileCheck %s
2
3; With sub reassociation, constant folding can eliminate the 12 and -12 constants.
4define i32 @test1(i32 %A, i32 %B) {
5; CHECK-LABEL: @test1
6; CHECK-NEXT: %Z = sub i32 %A, %B
7; CHECK-NEXT: ret i32 %Z
8  %X = add i32 -12, %A
9  %Y = sub i32 %X, %B
10  %Z = add i32 %Y, 12
11  ret i32 %Z
12}
13
14; PR2047
15; With sub reassociation, constant folding can eliminate the uses of %a.
16define i32 @test2(i32 %a, i32 %b, i32 %c) nounwind  {
17; CHECK-LABEL: @test2
18; CHECK-NEXT: %sum = add i32 %c, %b
19; CHECK-NEXT: %tmp7 = sub i32 0, %sum
20; CHECK-NEXT: ret i32 %tmp7
21
22  %tmp3 = sub i32 %a, %b
23  %tmp5 = sub i32 %tmp3, %c
24  %tmp7 = sub i32 %tmp5, %a
25  ret i32 %tmp7
26}
27