1 ; RUN: llc < %s -march=arm | FileCheck %s 2 3 ; This loop is rewritten with an indvar which counts down, which 4 ; frees up a register from holding the trip count. 5 6 define void @test(i32* %P, i32 %A, i32 %i) nounwind { 7 entry: 8 ; CHECK: str r1, [{{r.*}}, {{r.*}}, lsl #2] 9 icmp eq i32 %i, 0 ; <i1>:0 [#uses=1] 10 br i1 %0, label %return, label %bb 11 12 bb: ; preds = %bb, %entry 13 %indvar = phi i32 [ 0, %entry ], [ %indvar.next, %bb ] ; <i32> [#uses=2] 14 %i_addr.09.0 = sub i32 %i, %indvar ; <i32> [#uses=1] 15 %tmp2 = getelementptr i32* %P, i32 %i_addr.09.0 ; <i32*> [#uses=1] 16 store i32 %A, i32* %tmp2 17 %indvar.next = add i32 %indvar, 1 ; <i32> [#uses=2] 18 icmp eq i32 %indvar.next, %i ; <i1>:1 [#uses=1] 19 br i1 %1, label %return, label %bb 20 21 return: ; preds = %bb, %entry 22 ret void 23 } 24 25 ; This loop has a non-address use of the count-up indvar, so 26 ; it'll remain. Now the original store uses a negative-stride address. 27 28 define void @test_with_forced_iv(i32* %P, i32 %A, i32 %i) nounwind { 29 entry: 30 ; CHECK: str r1, [{{r.*}}, -{{r.*}}, lsl #2] 31 icmp eq i32 %i, 0 ; <i1>:0 [#uses=1] 32 br i1 %0, label %return, label %bb 33 34 bb: ; preds = %bb, %entry 35 %indvar = phi i32 [ 0, %entry ], [ %indvar.next, %bb ] ; <i32> [#uses=2] 36 %i_addr.09.0 = sub i32 %i, %indvar ; <i32> [#uses=1] 37 %tmp2 = getelementptr i32* %P, i32 %i_addr.09.0 ; <i32*> [#uses=1] 38 store i32 %A, i32* %tmp2 39 store i32 %indvar, i32* null 40 %indvar.next = add i32 %indvar, 1 ; <i32> [#uses=2] 41 icmp eq i32 %indvar.next, %i ; <i1>:1 [#uses=1] 42 br i1 %1, label %return, label %bb 43 44 return: ; preds = %bb, %entry 45 ret void 46 } 47 48
