From 59d179e9d2971e8b9abd1d5f01e6815f2ac02b3e Mon Sep 17 00:00:00 2001 From: Jordan Rose Date: Sat, 23 Mar 2013 01:21:23 +0000 Subject: [analyzer] Also transform "a < b" to "(b - a) > 0" in the constraint manager. We can support the full range of comparison operations between two locations by canonicalizing them as subtraction, as in the previous commit. This won't work (well) if either location includes an offset, or (again) if the comparisons are not consistent about which region comes first. llvm-svn: 177803 --- clang/test/Analysis/ptr-arith.c | 44 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 44 insertions(+) (limited to 'clang/test/Analysis/ptr-arith.c') diff --git a/clang/test/Analysis/ptr-arith.c b/clang/test/Analysis/ptr-arith.c index d9c5a0ff999..35faff4a170 100644 --- a/clang/test/Analysis/ptr-arith.c +++ b/clang/test/Analysis/ptr-arith.c @@ -204,6 +204,50 @@ void zero_implies_equal(int *lhs, int *rhs) { clang_analyzer_eval(lhs != rhs); // expected-warning{{TRUE}} } +void comparisons_imply_size(int *lhs, int *rhs) { + clang_analyzer_eval(lhs <= rhs); // expected-warning{{UNKNOWN}} + + if (lhs > rhs) { + clang_analyzer_eval((rhs - lhs) == 0); // expected-warning{{FALSE}} + return; + } + + clang_analyzer_eval(lhs <= rhs); // expected-warning{{TRUE}} + clang_analyzer_eval((rhs - lhs) >= 0); // expected-warning{{TRUE}} + clang_analyzer_eval((rhs - lhs) > 0); // expected-warning{{UNKNOWN}} + + if (lhs >= rhs) { + clang_analyzer_eval((rhs - lhs) == 0); // expected-warning{{TRUE}} + return; + } + + clang_analyzer_eval(lhs == rhs); // expected-warning{{FALSE}} + clang_analyzer_eval(lhs < rhs); // expected-warning{{TRUE}} + clang_analyzer_eval((rhs - lhs) > 0); // expected-warning{{TRUE}} +} + +void size_implies_comparison(int *lhs, int *rhs) { + clang_analyzer_eval(lhs <= rhs); // expected-warning{{UNKNOWN}} + + if ((rhs - lhs) < 0) { + clang_analyzer_eval(lhs == rhs); // expected-warning{{FALSE}} + return; + } + + clang_analyzer_eval(lhs <= rhs); // expected-warning{{TRUE}} + clang_analyzer_eval((rhs - lhs) >= 0); // expected-warning{{TRUE}} + clang_analyzer_eval((rhs - lhs) > 0); // expected-warning{{UNKNOWN}} + + if ((rhs - lhs) <= 0) { + clang_analyzer_eval(lhs == rhs); // expected-warning{{TRUE}} + return; + } + + clang_analyzer_eval(lhs == rhs); // expected-warning{{FALSE}} + clang_analyzer_eval(lhs < rhs); // expected-warning{{TRUE}} + clang_analyzer_eval((rhs - lhs) > 0); // expected-warning{{TRUE}} +} + //------------------------------- // False positives //------------------------------- -- cgit v1.2.3