From 3f2f8aa30b35bb87fa7b7aa914233437b5d68cb2 Mon Sep 17 00:00:00 2001 From: Timotej Kapus Date: Tue, 5 Nov 2019 09:53:03 +0000 Subject: [optimize-array] Fix hash collisions The caching maps in ArrayExpr are broken, they only consider hashes and don't check for structural equality. This can lead to hash collisions and invalid Expr replacement. This is especially potetent for UpdateLists, who only put the array name in the hash, so there can be a lot of colisions. --- lib/Expr/ArrayExprVisitor.cpp | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) (limited to 'lib/Expr/ArrayExprVisitor.cpp') diff --git a/lib/Expr/ArrayExprVisitor.cpp b/lib/Expr/ArrayExprVisitor.cpp index e4ea9a1c..75604104 100644 --- a/lib/Expr/ArrayExprVisitor.cpp +++ b/lib/Expr/ArrayExprVisitor.cpp @@ -183,16 +183,16 @@ ExprVisitor::Action IndexTransformationExprVisitor::visitMul(const MulExpr &e) { ExprVisitor::Action ArrayReadExprVisitor::visitConcat(const ConcatExpr &ce) { ReadExpr *base = ArrayExprHelper::hasOrderedReads(ce); if (base) { - return inspectRead(ce.hash(), ce.getWidth(), *base); + return inspectRead(const_cast(&ce), ce.getWidth(), *base); } return Action::doChildren(); } ExprVisitor::Action ArrayReadExprVisitor::visitRead(const ReadExpr &re) { - return inspectRead(re.hash(), re.getWidth(), re); + return inspectRead(const_cast(&re), re.getWidth(), re); } // This method is a mess because I want to avoid looping over the UpdateList // values twice -ExprVisitor::Action ArrayReadExprVisitor::inspectRead(unsigned hash, +ExprVisitor::Action ArrayReadExprVisitor::inspectRead(ref hash, Expr::Width width, const ReadExpr &re) { // pre(*): index is symbolic @@ -243,14 +243,14 @@ ExprVisitor::Action ArrayReadExprVisitor::inspectRead(unsigned hash, ExprVisitor::Action ArrayValueOptReplaceVisitor::visitConcat(const ConcatExpr &ce) { - auto found = optimized.find(ce.hash()); + auto found = optimized.find(const_cast(&ce)); if (found != optimized.end()) { return Action::changeTo((*found).second.get()); } return Action::doChildren(); } ExprVisitor::Action ArrayValueOptReplaceVisitor::visitRead(const ReadExpr &re) { - auto found = optimized.find(re.hash()); + auto found = optimized.find(const_cast(&re)); if (found != optimized.end()) { return Action::changeTo((*found).second.get()); } -- cgit 1.4.1