Author: henrywong Date: Sat Mar 31 05:46:46 2018 New Revision: 328919 URL: http://llvm.org/viewvc/llvm-project?rev=328919&view=rev Log: [analyzer] Unroll the loop when it has a unsigned counter.
Summary: The original implementation in the `LoopUnrolling.cpp` didn't consider the case where the counter is unsigned. This case is only handled in `simpleCondition()`, but this is not enough, we also need to deal with the unsinged counter with the counter initialization. Since `IntegerLiteral` is `signed`, there is a `ImplicitCastExpr<IntegralCast>` in `unsigned counter = IntergerLiteral`. This patch add the `ignoringParenImpCasts()` in the `IntegerLiteral` matcher. Reviewers: szepet, a.sidorin, NoQ, george.karpenkov Reviewed By: szepet, george.karpenkov Subscribers: xazax.hun, rnkovacs, cfe-commits, MTC Differential Revision: https://reviews.llvm.org/D45086 Modified: cfe/trunk/lib/StaticAnalyzer/Core/LoopUnrolling.cpp cfe/trunk/test/Analysis/loop-unrolling.cpp Modified: cfe/trunk/lib/StaticAnalyzer/Core/LoopUnrolling.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/StaticAnalyzer/Core/LoopUnrolling.cpp?rev=328919&r1=328918&r2=328919&view=diff ============================================================================== --- cfe/trunk/lib/StaticAnalyzer/Core/LoopUnrolling.cpp (original) +++ cfe/trunk/lib/StaticAnalyzer/Core/LoopUnrolling.cpp Sat Mar 31 05:46:46 2018 @@ -141,13 +141,15 @@ static internal::Matcher<Stmt> forLoopMa return forStmt( hasCondition(simpleCondition("initVarName")), // Initialization should match the form: 'int i = 6' or 'i = 42'. - hasLoopInit(anyOf( - declStmt(hasSingleDecl(varDecl( - allOf(hasInitializer(integerLiteral().bind("initNum")), - equalsBoundNode("initVarName"))))), - binaryOperator(hasLHS(declRefExpr(to( - varDecl(equalsBoundNode("initVarName"))))), - hasRHS(integerLiteral().bind("initNum"))))), + hasLoopInit( + anyOf(declStmt(hasSingleDecl( + varDecl(allOf(hasInitializer(ignoringParenImpCasts( + integerLiteral().bind("initNum"))), + equalsBoundNode("initVarName"))))), + binaryOperator(hasLHS(declRefExpr(to(varDecl( + equalsBoundNode("initVarName"))))), + hasRHS(ignoringParenImpCasts( + integerLiteral().bind("initNum")))))), // Incrementation should be a simple increment or decrement // operator call. hasIncrement(unaryOperator( Modified: cfe/trunk/test/Analysis/loop-unrolling.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Analysis/loop-unrolling.cpp?rev=328919&r1=328918&r2=328919&view=diff ============================================================================== --- cfe/trunk/test/Analysis/loop-unrolling.cpp (original) +++ cfe/trunk/test/Analysis/loop-unrolling.cpp Sat Mar 31 05:46:46 2018 @@ -36,6 +36,29 @@ int simple_unroll2() { return 0; } +int simple_unroll3_unsigned() { + int a[9]; + int k = 42; + for (unsigned i = 0; i < 9; i++) { + clang_analyzer_numTimesReached(); // expected-warning {{9}} + a[i] = 42; + } + int b = 22 / (k - 42); // expected-warning {{Division by zero}} + return 0; +} + +int simple_unroll4_unsigned() { + int a[9]; + int k = 42; + unsigned i; + for (i = (0); i < 9; i++) { + clang_analyzer_numTimesReached(); // expected-warning {{9}} + a[i] = 42; + } + int b = 22 / (k - 42); // expected-warning {{Division by zero}} + return 0; +} + int simple_no_unroll1() { int a[9]; int k = 42; _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
