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; RUN: llc -mtriple=arm-eabi %s -o - | FileCheck %s
; This loop is rewritten with an indvar which counts down, which
; frees up a register from holding the trip count.
define void @test(ptr %P, i32 %A, i32 %i) nounwind {
entry:
; CHECK: str r1, [{{r.*}}, {{r.*}}, lsl #2]
icmp eq i32 %i, 0 ; <i1>:0 [#uses=1]
br i1 %0, label %return, label %bb
bb: ; preds = %bb, %entry
%indvar = phi i32 [ 0, %entry ], [ %indvar.next, %bb ] ; <i32> [#uses=2]
%i_addr.09.0 = sub i32 %i, %indvar ; <i32> [#uses=1]
%tmp2 = getelementptr i32, ptr %P, i32 %i_addr.09.0 ; <ptr> [#uses=1]
store i32 %A, ptr %tmp2
%indvar.next = add i32 %indvar, 1 ; <i32> [#uses=2]
icmp eq i32 %indvar.next, %i ; <i1>:1 [#uses=1]
br i1 %1, label %return, label %bb
return: ; preds = %bb, %entry
ret void
}
; This loop has a non-address use of the count-up indvar, so
; it'll remain. Now the original store uses a negative-stride address.
define void @test_with_forced_iv(ptr %P, i32 %A, i32 %i) nounwind {
entry:
; CHECK: str r1, [{{r.*}}, -{{r.*}}, lsl #2]
icmp eq i32 %i, 0 ; <i1>:0 [#uses=1]
br i1 %0, label %return, label %bb
bb: ; preds = %bb, %entry
%indvar = phi i32 [ 0, %entry ], [ %indvar.next, %bb ] ; <i32> [#uses=2]
%i_addr.09.0 = sub i32 %i, %indvar ; <i32> [#uses=1]
%tmp2 = getelementptr i32, ptr %P, i32 %i_addr.09.0 ; <ptr> [#uses=1]
store i32 %A, ptr %tmp2
store i32 %indvar, ptr null
%indvar.next = add i32 %indvar, 1 ; <i32> [#uses=2]
icmp eq i32 %indvar.next, %i ; <i1>:1 [#uses=1]
br i1 %1, label %return, label %bb
return: ; preds = %bb, %entry
ret void
}
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