diff options
| -rw-r--r-- | lib/Core/ExecutorUtil.cpp | 24 | ||||
| -rw-r--r-- | test/Feature/ConstExprWithDivZero.ll | 18 | ||||
| -rw-r--r-- | test/Feature/ConstExprWithOvershift.ll | 16 |
3 files changed, 58 insertions, 0 deletions
diff --git a/lib/Core/ExecutorUtil.cpp b/lib/Core/ExecutorUtil.cpp index 0a8f08ed..bd8aa200 100644 --- a/lib/Core/ExecutorUtil.cpp +++ b/lib/Core/ExecutorUtil.cpp @@ -126,6 +126,30 @@ namespace klee { if (numOperands > 1) op2 = evalConstant(ce->getOperand(1), ki); if (numOperands > 2) op3 = evalConstant(ce->getOperand(2), ki); + /* Checking for possible errors during constant folding */ + switch (ce->getOpcode()) { + case Instruction::SDiv: + case Instruction::UDiv: + case Instruction::SRem: + case Instruction::URem: + if (op2->getLimitedValue() == 0) { + std::string msg("Division/modulo by zero during constant folding at location "); + llvm::raw_string_ostream os(msg); + os << (ki ? ki->printFileLine().c_str() : "[unknown]"); + klee_error("%s", os.str().c_str()); + } + break; + case Instruction::Shl: + case Instruction::LShr: + case Instruction::AShr: + if (op2->getLimitedValue() >= op1->getWidth()) { + std::string msg("Overshift during constant folding at location "); + llvm::raw_string_ostream os(msg); + os << (ki ? ki->printFileLine().c_str() : "[unknown]"); + klee_error("%s", os.str().c_str()); + } + } + std::string msg("Unknown ConstantExpr type"); llvm::raw_string_ostream os(msg); diff --git a/test/Feature/ConstExprWithDivZero.ll b/test/Feature/ConstExprWithDivZero.ll new file mode 100644 index 00000000..f430dad9 --- /dev/null +++ b/test/Feature/ConstExprWithDivZero.ll @@ -0,0 +1,18 @@ +; REQUIRES: llvm-3.4 +; RUN: llvm-as %s -f -o %t.bc +; RUN: rm -rf %t.klee-out +; RUN: not %klee --output-dir=%t.klee-out %t.bc 2> %t.log +; RUN: FileCheck --input-file %t.log %s + +; See https://github.com/klee/klee/issues/268 + +target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128" +target triple = "x86_64-pc-linux-gnu" + +@a = internal global i32 0, align 4 +@b = internal global [1 x i32] [i32 1], align 4 + +define i32 @main() { +; CHECK: Division/modulo by zero during constant folding + ret i32 trunc (i64 sdiv (i64 2036854775807, i64 sext (i32 select (i1 icmp eq (i32* getelementptr inbounds ([1 x i32]* @b, i64 0, i64 0), i32* @a), i32 1, i32 0) to i64)) to i32) +} diff --git a/test/Feature/ConstExprWithOvershift.ll b/test/Feature/ConstExprWithOvershift.ll new file mode 100644 index 00000000..7d4a1284 --- /dev/null +++ b/test/Feature/ConstExprWithOvershift.ll @@ -0,0 +1,16 @@ +; REQUIRES: llvm-3.4 +; RUN: llvm-as %s -f -o %t.bc +; RUN: rm -rf %t.klee-out +; RUN: not %klee --output-dir=%t.klee-out %t.bc 2> %t.log +; RUN: FileCheck --input-file %t.log %s + +target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128" +target triple = "x86_64-pc-linux-gnu" + +@a = internal global i32 0, align 4 +@b = internal global [1 x i32] [i32 1], align 4 + +define i32 @main() { +; CHECK: Overshift during constant folding + ret i32 ashr (i32 zext (i1 icmp ne (i32* getelementptr inbounds ([1 x i32]* @b, i64 0, i64 0), i32* @a) to i32), i32 trunc (i64 add (i64 zext (i1 icmp ne (i32* getelementptr inbounds ([1 x i32]* @b, i64 0, i64 0), i32* @a) to i64), i64 31) to i32)) +} |