office-gobmx/compilerplugins/clang/intvsfloat.cxx
Stephan Bergmann 5d546de67b Adapt to Clang 12 trunk RecursiveASTVisitor change
<https://github.com/llvm/llvm-project/commit/
5689b38c6a4220cc5f6ba68a56486229b10071bf> "Removed a RecursiveASTVisitor feature
to visit operator kinds with different methods".

That change is incompatible in that before the change individual TraverseUnary*
and TraverseBin* functions were called, while now TraverseUnaryOperator and
TraverseBinaryOperator/TraverseCompoundAssignOperator are called for all the
different operators.  Fixed that with a few #if for the non-shared plugins, but
that doesn't work for the shared plugin.  So made the two affected plugins non-
shared for now and left a better fix as a TODO.

Change-Id: I5b87d329ae2c4c93bf605bb1ecc9641039f014a3
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/99000
Tested-by: Jenkins
Reviewed-by: Stephan Bergmann <sbergman@redhat.com>
2020-07-19 23:05:57 +02:00

117 lines
3.5 KiB
C++

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
* This file is part of the LibreOffice project.
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*/
#ifndef LO_CLANG_SHARED_PLUGINS
#include "plugin.hxx"
#include "check.hxx"
#include "compat.hxx"
#include <iostream>
/**
TODO multiplying/otherop on a combination of a float and int, and then truncating to int. like this:
float getRotation() {}
int moRotation = -F_PI180 * 90 * getRotation();
*/
namespace
{
class IntVsFloat : public loplugin::FilteringPlugin<IntVsFloat>
{
public:
explicit IntVsFloat(loplugin::InstantiationData const& data)
: loplugin::FilteringPlugin<IntVsFloat>(data)
{
}
void run() override { TraverseDecl(compiler.getASTContext().getTranslationUnitDecl()); }
bool VisitVarDecl(VarDecl const*);
bool VisitBinaryOperator(BinaryOperator const*);
private:
llvm::Optional<double> getExprValue(Expr const* expr);
};
bool IntVsFloat::VisitVarDecl(VarDecl const* varDecl)
{
if (ignoreLocation(varDecl->getLocation()))
return true;
auto init = varDecl->getInit();
if (!init)
return true;
init = init->IgnoreImpCasts();
if (varDecl->getType()->isFloatingType())
return true;
// init->dump();
llvm::Optional<double> d = getExprValue(init);
if (!d)
return true;
if (static_cast<long>(*d) == *d)
return true;
report(DiagnosticsEngine::Warning, "assigning constant float value to int truncates data",
compat::getBeginLoc(init))
<< init->getSourceRange();
return true;
}
bool IntVsFloat::VisitBinaryOperator(BinaryOperator const* op)
{
if (op->getOpcode() != BO_EQ)
{
return true;
}
if (ignoreLocation(compat::getBeginLoc(op)))
return true;
auto lhs = op->getLHS()->IgnoreImpCasts();
auto rhs = op->getRHS()->IgnoreImpCasts();
if (!lhs->getType()->isFloatingType())
std::swap(lhs, rhs);
if (!lhs->getType()->isFloatingType())
return true;
if (rhs->getType()->isFloatingType())
return true;
llvm::Optional<double> d = getExprValue(lhs);
if (!d)
return true;
if (static_cast<long>(*d) == *d)
return true;
report(DiagnosticsEngine::Warning, "comparing integer to float constant, can never be true",
compat::getBeginLoc(op))
<< op->getSourceRange();
return true;
}
llvm::Optional<double> IntVsFloat::getExprValue(Expr const* expr)
{
// Of the available clang Evaluate* APIs, this is the __only__ one that produces useful output
// (as of 17 Aug 2018 checkout of clang, ie. towards clang 7)
if (expr->isValueDependent())
return llvm::Optional<double>();
Expr::EvalResult evalResult;
if (!expr->EvaluateAsRValue(evalResult, compiler.getASTContext()))
return llvm::Optional<double>();
if (!evalResult.Val.isFloat())
return llvm::Optional<double>();
llvm::APFloat floatResult = evalResult.Val.getFloat();
bool losesInfo;
floatResult.convert(APFloat::IEEEdouble(), APFloat::rmNearestTiesToEven, &losesInfo);
double d = floatResult.convertToDouble();
return d;
}
loplugin::Plugin::Registration<IntVsFloat> intvsfloat("intvsfloat");
} // namespace
#endif // LO_CLANG_SHARED_PLUGINS
/* vim:set shiftwidth=4 softtabstop=4 expandtab: */