From 28c81638a8a42ca294819e8152e4e722ce0da081 Mon Sep 17 00:00:00 2001 From: Dale Johannesen Date: Mon, 15 Jun 2009 20:59:27 +0000 Subject: Fix the crash in this test. This is basically the same problem addressed in 31284, but the patch there only addressed the case where an invoke is the first thing in a block. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73416 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Transforms/Utils/SimplifyCFG.cpp | 29 +++++++++++++++++++++++++++-- 1 file changed, 27 insertions(+), 2 deletions(-) (limited to 'lib/Transforms/Utils') diff --git a/lib/Transforms/Utils/SimplifyCFG.cpp b/lib/Transforms/Utils/SimplifyCFG.cpp index bcc6b81..ee0f6a6 100644 --- a/lib/Transforms/Utils/SimplifyCFG.cpp +++ b/lib/Transforms/Utils/SimplifyCFG.cpp @@ -859,6 +859,26 @@ static bool FoldValueComparisonIntoPredecessors(TerminatorInst *TI) { return Changed; } +// isSafeToHoistInvoke - If we would need to insert a select that uses the +// value of this invoke (comments in HoistThenElseCodeToIf explain why we +// would need to do this), we can't hoist the invoke, as there is nowhere +// to put the select in this case. +static bool isSafeToHoistInvoke(BasicBlock *BB1, BasicBlock *BB2, + Instruction *I1, Instruction *I2) { + for (succ_iterator SI = succ_begin(BB1), E = succ_end(BB1); SI != E; ++SI) { + PHINode *PN; + for (BasicBlock::iterator BBI = SI->begin(); + (PN = dyn_cast(BBI)); ++BBI) { + Value *BB1V = PN->getIncomingValueForBlock(BB1); + Value *BB2V = PN->getIncomingValueForBlock(BB2); + if (BB1V != BB2V && (BB1V==I1 || BB2V==I2)) { + return false; + } + } + } + return true; +} + /// HoistThenElseCodeToIf - Given a conditional branch that goes to BB1 and /// BB2, hoist any common code in the two blocks up into the branch block. The /// caller of this function guarantees that BI's block dominates BB1 and BB2. @@ -879,8 +899,9 @@ static bool HoistThenElseCodeToIf(BranchInst *BI) { I1 = BB1_Itr++; while (isa(I2)) I2 = BB2_Itr++; - if (I1->getOpcode() != I2->getOpcode() || isa(I1) || - isa(I1) || !I1->isIdenticalTo(I2)) + if (I1->getOpcode() != I2->getOpcode() || isa(I1) || + !I1->isIdenticalTo(I2) || + (isa(I1) && !isSafeToHoistInvoke(BB1, BB2, I1, I2))) return false; // If we get here, we can hoist at least one instruction. @@ -911,6 +932,10 @@ static bool HoistThenElseCodeToIf(BranchInst *BI) { return true; HoistTerminator: + // It may not be possible to hoist an invoke. + if (isa(I1) && !isSafeToHoistInvoke(BB1, BB2, I1, I2)) + return true; + // Okay, it is safe to hoist the terminator. Instruction *NT = I1->clone(); BIParent->getInstList().insert(BI, NT); -- cgit v1.1