From 580bba2b0dd2173c899699a87e109bfd1482c001 Mon Sep 17 00:00:00 2001 From: Jakob Stoklund Olesen Date: Fri, 5 Mar 2010 21:49:10 +0000 Subject: [PATCH] Avoid creating bad PHI instructions when BR is being const-folded. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97836 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp | 2 + .../CodeGen/X86/2010-03-05-ConstantFoldCFG.ll | 42 +++++++++++++++++++ 2 files changed, 44 insertions(+) create mode 100644 test/CodeGen/X86/2010-03-05-ConstantFoldCFG.ll diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp index f426fb1f3fa..05f9f1ff186 100644 --- a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp +++ b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp @@ -1038,6 +1038,8 @@ SelectionDAGISel::FinishBasicBlock() { MachineInstr *PHI = SDB->PHINodesToUpdate[i].first; assert(PHI->isPHI() && "This is not a machine PHI node that we are updating!"); + if (!BB->isSuccessor(PHI->getParent())) + continue; PHI->addOperand(MachineOperand::CreateReg(SDB->PHINodesToUpdate[i].second, false)); PHI->addOperand(MachineOperand::CreateMBB(BB)); diff --git a/test/CodeGen/X86/2010-03-05-ConstantFoldCFG.ll b/test/CodeGen/X86/2010-03-05-ConstantFoldCFG.ll new file mode 100644 index 00000000000..5de19662fff --- /dev/null +++ b/test/CodeGen/X86/2010-03-05-ConstantFoldCFG.ll @@ -0,0 +1,42 @@ +; RUN: llc < %s -verify-machineinstrs +; +; When BRCOND is constant-folded to BR, make sure that PHI nodes don't get +; spurious operands when the CFG is trimmed. +; +target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64" +target triple = "x86_64-apple-darwin10.2" + +define fastcc void @_ZSt16__introsort_loopIPdl17less_than_functorEvT_S2_T0_T1_(double* %__first, double* %__last, i64 %__depth_limit) nounwind ssp { +entry: + br i1 undef, label %bb1, label %bb2 + +bb1: ; preds = %entry + ret void + +bb2: ; preds = %entry + br label %bb2.outer.i + +bb2.outer.i: ; preds = %bb9.i, %bb2 + br i1 undef, label %bb1.i, label %bb5.preheader.i + +bb1.i: ; preds = %bb1.i, %bb2.outer.i + %indvar5.i = phi i64 [ %tmp, %bb1.i ], [ 0, %bb2.outer.i ] ; [#uses=1] + %tmp = add i64 %indvar5.i, 1 ; [#uses=2] + %scevgep.i = getelementptr double* undef, i64 %tmp ; [#uses=0] + br i1 undef, label %bb1.i, label %bb5.preheader.i + +bb5.preheader.i: ; preds = %bb1.i, %bb2.outer.i + br label %bb5.i + +bb5.i: ; preds = %bb5.i, %bb5.preheader.i + br i1 undef, label %bb5.i, label %bb7.i6 + +bb7.i6: ; preds = %bb5.i + br i1 undef, label %bb9.i, label %_ZSt21__unguarded_partitionIPdd17less_than_functorET_S2_S2_T0_T1_.exit + +bb9.i: ; preds = %bb7.i6 + br label %bb2.outer.i + +_ZSt21__unguarded_partitionIPdd17less_than_functorET_S2_S2_T0_T1_.exit: ; preds = %bb7.i6 + unreachable +}