llvm/test/CodeGen/AArch64/br-undef-cond.ll
Ahmed Bougacha 75da31ff15 [AArch64] Keep flags on condition vreg when instantiating a CB branch.
Reversing a CB* instruction used to drop the flags on the condition. On the
included testcase, this lead to a read from an undefined vreg.
Using addOperand keeps the flags, here <undef>.

Differential Revision: http://reviews.llvm.org/D6159


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221507 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-07 02:50:00 +00:00

27 lines
600 B
LLVM

; RUN: llc < %s -verify-machineinstrs
; Make sure we don't end up with a CBNZ of an undef v-/phys-reg.
target datalayout = "e-m:o-i64:64-i128:128-n32:64-S128"
target triple = "arm64-apple-ios"
declare void @bar(i8*)
define void @foo(i8* %m, i32 %off0) {
.thread1653:
br i1 undef, label %0, label %.thread1880
%1 = icmp eq i32 undef, 0
%.not = xor i1 %1, true
%brmerge = or i1 %.not, undef
br i1 %brmerge, label %.thread1880, label %.thread1705
.thread1705:
ret void
.thread1880:
%m1652.ph = phi i8* [ %m, %0 ], [ null, %.thread1653 ]
call void @bar(i8* %m1652.ph)
ret void
}