1 ; RUN: opt < %s -indvars -S | FileCheck %s 2 3 ; This tests that the IV is not recomputed outside of the loop when it is known 4 ; to be computed by the loop and used in the loop any way. In the example below 5 ; although a's value can be computed outside of the loop, there is no benefit 6 ; in doing so as it has to be computed by the loop anyway. 7 ; 8 ; extern void func(unsigned val); 9 ; 10 ; void test(unsigned m) 11 ; { 12 ; unsigned a = 0; 13 ; 14 ; for (int i=0; i<186; i++) { 15 ; a += m; 16 ; func(a); 17 ; } 18 ; 19 ; func(a); 20 ; } 21 22 declare void @func(i32) 23 24 ; CHECK-LABEL: @test( 25 define void @test(i32 %m) nounwind uwtable { 26 entry: 27 br label %for.body 28 29 for.body: ; preds = %for.body, %entry 30 %i.06 = phi i32 [ 0, %entry ], [ %inc, %for.body ] 31 %a.05 = phi i32 [ 0, %entry ], [ %add, %for.body ] 32 %add = add i32 %a.05, %m 33 ; CHECK: tail call void @func(i32 %add) 34 tail call void @func(i32 %add) 35 %inc = add nsw i32 %i.06, 1 36 %exitcond = icmp eq i32 %inc, 186 37 br i1 %exitcond, label %for.end, label %for.body 38 39 for.end: ; preds = %for.body 40 ; CHECK: for.end: 41 ; CHECK-NOT: mul i32 %m, 186 42 ; CHECK:%add.lcssa = phi i32 [ %add, %for.body ] 43 ; CHECK-NEXT: tail call void @func(i32 %add.lcssa) 44 tail call void @func(i32 %add) 45 ret void 46 } 47 48 ; CHECK-LABEL: @test2( 49 define i32 @test2(i32 %m) nounwind uwtable { 50 entry: 51 br label %for.body 52 53 for.body: ; preds = %for.body, %entry 54 %i.06 = phi i32 [ 0, %entry ], [ %inc, %for.body ] 55 %a.05 = phi i32 [ 0, %entry ], [ %add, %for.body ] 56 %add = add i32 %a.05, %m 57 ; CHECK: tail call void @func(i32 %add) 58 tail call void @func(i32 %add) 59 %inc = add nsw i32 %i.06, 1 60 %exitcond = icmp eq i32 %inc, 186 61 br i1 %exitcond, label %for.end, label %for.body 62 63 for.end: ; preds = %for.body 64 ; CHECK: for.end: 65 ; CHECK-NOT: mul i32 %m, 186 66 ; CHECK:%add.lcssa = phi i32 [ %add, %for.body ] 67 ; CHECK-NEXT: ret i32 %add.lcssa 68 ret i32 %add 69 } 70
