From be9fe49b179a89a659fe786d64b176d2b360bb4a Mon Sep 17 00:00:00 2001
From: Lang Hames <lhames@gmail.com>
Date: Mon, 2 Apr 2012 19:58:43 +0000
Subject: [PATCH] During two-address lowering, rescheduling an instruction does
 not untie operands. Make TryInstructionTransform return false to reflect
 this. Fixes PR11861.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153892 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/CodeGen/TwoAddressInstructionPass.cpp     |  4 ++--
 .../ARM/2012-04-02-TwoAddrInstrCrash.ll       | 24 +++++++++++++++++++
 2 files changed, 26 insertions(+), 2 deletions(-)
 create mode 100644 test/CodeGen/ARM/2012-04-02-TwoAddrInstrCrash.ll

diff --git a/lib/CodeGen/TwoAddressInstructionPass.cpp b/lib/CodeGen/TwoAddressInstructionPass.cpp
index 24b8bc2048a..789617ba7fc 100644
--- a/lib/CodeGen/TwoAddressInstructionPass.cpp
+++ b/lib/CodeGen/TwoAddressInstructionPass.cpp
@@ -1248,7 +1248,7 @@ TryInstructionTransform(MachineBasicBlock::iterator &mi,
   // re-schedule this MI below it.
   if (RescheduleMIBelowKill(mbbi, mi, nmi, regB)) {
     ++NumReSchedDowns;
-    return true;
+    return false;
   }
 
   if (TargetRegisterInfo::isVirtualRegister(regA))
@@ -1270,7 +1270,7 @@ TryInstructionTransform(MachineBasicBlock::iterator &mi,
   // re-schedule it before this MI if it's legal.
   if (RescheduleKillAboveMI(mbbi, mi, nmi, regB)) {
     ++NumReSchedUps;
-    return true;
+    return false;
   }
 
   // If this is an instruction with a load folded into it, try unfolding
diff --git a/test/CodeGen/ARM/2012-04-02-TwoAddrInstrCrash.ll b/test/CodeGen/ARM/2012-04-02-TwoAddrInstrCrash.ll
new file mode 100644
index 00000000000..33ad187926b
--- /dev/null
+++ b/test/CodeGen/ARM/2012-04-02-TwoAddrInstrCrash.ll
@@ -0,0 +1,24 @@
+; RUN: llc < %s
+; PR11861
+target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:64:128-a0:0:64-n32-S64"
+target triple = "armv7-none-linux-gnueabi"
+
+define arm_aapcs_vfpcc void @foo() nounwind align 2 {
+  br i1 undef, label %5, label %1
+
+; <label>:1                                       ; preds = %0
+  %2 = shufflevector <1 x i64> zeroinitializer, <1 x i64> undef, <2 x i32> <i32 0, i32 1>
+  %3 = bitcast <2 x i64> %2 to <4 x float>
+  store <4 x float> zeroinitializer, <4 x float>* undef, align 16, !tbaa !0
+  store <4 x float> zeroinitializer, <4 x float>* undef, align 16, !tbaa !0
+  store <4 x float> %3, <4 x float>* undef, align 16, !tbaa !0
+  %4 = insertelement <4 x float> %3, float 8.000000e+00, i32 2
+  store <4 x float> %4, <4 x float>* undef, align 16, !tbaa !0
+  unreachable
+
+; <label>:5                                       ; preds = %0
+  ret void
+}
+
+!0 = metadata !{metadata !"omnipotent char", metadata !1}
+!1 = metadata !{metadata !"Simple C/C++ TBAA", null}
-- 
2.34.1