2011-03-23-PeepholeBug.ll
1.12 KB
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; RUN: llc < %s -mtriple=thumbv7-apple-darwin10 -relocation-model=pic -frame-pointer=all -mcpu=cortex-a8 | FileCheck %s
; subs r4, #1
; cmp r4, 0
; bgt
; cmp cannot be optimized away since it will clear the overflow bit.
; gt / ge, lt, le conditions all depend on V bit.
; rdar://9172742
define i32 @t() nounwind {
; CHECK-LABEL: t:
entry:
br label %bb2
bb: ; preds = %bb2
%0 = tail call i32 @rand() nounwind
%1 = icmp eq i32 %0, 50
br i1 %1, label %bb3, label %bb1
bb1: ; preds = %bb
; CHECK: bb1
; CHECK: subs [[REG:r[0-9]+]], #1
%tmp = tail call i32 @puts() nounwind
%indvar.next = add i32 %indvar, 1
br label %bb2
bb2: ; preds = %bb1, %entry
; CHECK: cmp [[REG]], #0
; CHECK: bgt
%indvar = phi i32 [ %indvar.next, %bb1 ], [ 0, %entry ]
%tries.0 = sub i32 2147483647, %indvar
%tmp1 = icmp sgt i32 %tries.0, 0
br i1 %tmp1, label %bb, label %bb3
bb3: ; preds = %bb2, %bb
ret i32 0
}
declare i32 @rand()
declare i32 @puts() nounwind