diff options
author | Manuel Klimek <klimek@google.com> | 2014-08-07 16:05:51 +0000 |
---|---|---|
committer | Manuel Klimek <klimek@google.com> | 2014-08-07 16:05:51 +0000 |
commit | c8f9454fb468fdef89e0056322ef6e18fc7cd1c2 (patch) | |
tree | 797abdad3e39c70e441285dc99d76d1a7ba2b00a /lib/Analysis | |
parent | dc2fdc2c413dd4cfda859ae62ee8e2baa0542ea8 (diff) |
Model temporary destructors from logical operators with known values.
If the truth value of a LHS is known, we can build the knowledge whether
a temporary destructor is executed or not into the CFG. This is needed
by the return type analysis.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@215118 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/Analysis')
-rw-r--r-- | lib/Analysis/CFG.cpp | 19 |
1 files changed, 15 insertions, 4 deletions
diff --git a/lib/Analysis/CFG.cpp b/lib/Analysis/CFG.cpp index b9698d550b..96571fdbec 100644 --- a/lib/Analysis/CFG.cpp +++ b/lib/Analysis/CFG.cpp @@ -3631,12 +3631,23 @@ CFGBlock *CFGBuilder::VisitBinaryOperatorForTemporaryDtors( BinaryOperator *E, TempDtorContext &Context) { if (E->isLogicalOp()) { VisitForTemporaryDtors(E->getLHS(), false, Context); - // We do not know at CFG-construction time whether the right-hand-side was - // executed, thus we add a branch node that depends on the temporary - // constructor call. + TryResult LHSVal = tryEvaluateBool(E->getLHS()); + bool RHSNotExecuted = (E->getOpcode() == BO_LAnd && LHSVal.isFalse()) || + (E->getOpcode() == BO_LOr && LHSVal.isTrue()); + if (RHSNotExecuted) { + return Block; + } + TempDtorContext RHSContext(/*IsConditional=*/true); VisitForTemporaryDtors(E->getRHS(), false, RHSContext); - InsertTempDtorDecisionBlock(RHSContext); + + // If the LHS is known, and the RHS is not executed, we returned above. + // Thus, once we arrive here, and the LHS is known, we also know that the + // RHS was executed and can execute the RHS unconditionally (that is, we + // don't insert a decision block). + if (!LHSVal.isKnown()) + InsertTempDtorDecisionBlock(RHSContext); + return Block; } |