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1; RUN: llc -mtriple=arm-eabi %s -o - | FileCheck %s2 3; This loop is rewritten with an indvar which counts down, which4; frees up a register from holding the trip count.5 6define void @test(ptr %P, i32 %A, i32 %i) nounwind {7entry: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 %bb11 12bb:             ; preds = %bb, %entry13        %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, ptr %P, i32 %i_addr.09.0         ; <ptr> [#uses=1]16        store i32 %A, ptr %tmp217        %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 %bb20 21return:         ; preds = %bb, %entry22        ret void23}24 25; This loop has a non-address use of the count-up indvar, so26; it'll remain. Now the original store uses a negative-stride address.27 28define void @test_with_forced_iv(ptr %P, i32 %A, i32 %i) nounwind {29entry: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 %bb33 34bb:             ; preds = %bb, %entry35        %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, ptr %P, i32 %i_addr.09.0         ; <ptr> [#uses=1]38        store i32 %A, ptr %tmp239        store i32 %indvar, ptr null40        %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 %bb43 44return:         ; preds = %bb, %entry45        ret void46}47 48