llvm/test/Transforms/LoopUnroll/update-loop-info-in-subloops.ll
Duncan P. N. Exon Smith de7465af34 LoopUnroll: Create sub-loops in LoopInfo
`LoopUnrollPass` says that it preserves `LoopInfo` -- make it so.  In
particular, tell `LoopInfo` about copies of inner loops when unrolling
the outer loop.

Conservatively, also tell `ScalarEvolution` to forget about the original
versions of these loops, since their inputs may have changed.

Fixes PR20987.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219241 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-07 21:19:00 +00:00

36 lines
636 B
LLVM

; RUN: opt -S < %s -loop-unroll -block-freq | FileCheck %s
; Crasher from PR20987.
; CHECK: define void @update_loop_info_in_subloops
; CHECK: entry:
; CHECK: L:
; CHECK: L.inner:
; CHECK: L.inner.latch:
; CHECK: L.latch:
; CHECK: L.inner.1:
; CHECK: L.inner.latch.1:
; CHECK: L.latch.1:
define void @update_loop_info_in_subloops() {
entry:
br label %L
L:
%0 = phi i64 [ 1, %entry ], [ %1, %L.latch ]
br label %L.inner
L.inner:
br label %L.inner.latch
L.inner.latch:
br i1 false, label %L.latch, label %L.inner
L.latch:
%1 = add i64 %0, 1
%2 = icmp eq i64 %1, 3
br i1 %2, label %exit, label %L
exit:
ret void
}