From 642767a8f648c45c9dabaea089bdf48783ad4806 Mon Sep 17 00:00:00 2001 From: Jakob Stoklund Olesen Date: Tue, 15 Jun 2010 18:49:14 +0000 Subject: Fix an exotic bug that only showed up in an internal test case. SimpleRegisterCoalescing::JoinIntervals() uses CoalescerPair to determine if a copy is coalescable, and in very rare cases it can return true where LHS is not live - the coalescable copy can come from an alias of the physreg in LHS. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106021 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/CodeGen/SimpleRegisterCoalescing.cpp | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'lib') diff --git a/lib/CodeGen/SimpleRegisterCoalescing.cpp b/lib/CodeGen/SimpleRegisterCoalescing.cpp index 16d929b..6f3fc99 100644 --- a/lib/CodeGen/SimpleRegisterCoalescing.cpp +++ b/lib/CodeGen/SimpleRegisterCoalescing.cpp @@ -2310,7 +2310,8 @@ SimpleRegisterCoalescing::JoinIntervals(LiveInterval &LHS, LiveInterval &RHS, // Figure out the value # from the RHS. LiveRange *lr = RHS.getLiveRangeContaining(VNI->def.getPrevSlot()); - assert(lr && "Cannot find live range"); + // The copy could be to an aliased physreg. + if (!lr) continue; LHSValsDefinedFromRHS[VNI] = lr->valno; } @@ -2329,7 +2330,8 @@ SimpleRegisterCoalescing::JoinIntervals(LiveInterval &LHS, LiveInterval &RHS, // Figure out the value # from the LHS. LiveRange *lr = LHS.getLiveRangeContaining(VNI->def.getPrevSlot()); - assert(lr && "Cannot find live range"); + // The copy could be to an aliased physreg. + if (!lr) continue; RHSValsDefinedFromLHS[VNI] = lr->valno; } -- cgit v1.1