caio/clang-p2996
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

[ELF] - Report location for div/mod by zero.

Browse Source 
"division by zero" or "modulo by zero" are not
very informative errors and even probably confusing
as does not let to know that error is coming from linker script.
Patch adds location reporting.

Differential revision: https://reviews.llvm.org/D43934

llvm-svn: 326686
This commit is contained in:
George Rimar
2018-03-05 10:02:44 +00:00
parent 503da8ff1f
commit 7b91e2133e
2 changed files with 27 additions and 20 deletions
Download Patch File Download Diff File Expand all files Collapse all files

39
lld/ELF/ScriptParser.cpp
View File

@@ -98,6 +98,7 @@ private:
uint64_t readMemoryAssignment(StringRef, StringRef, StringRef);
std::pair<uint32_t, uint32_t> readMemoryAttributes();
Expr combine(StringRef Op, Expr L, Expr R);
Expr readExpr();
Expr readExpr1(Expr Lhs, int MinPrec);
StringRef readParenLiteral();
@@ -157,20 +158,6 @@ static ExprValue sub(ExprValue A, ExprValue B) {
return {A.Sec, false, A.getSectionOffset() - B.getValue(), A.Loc};
}
static ExprValue div(ExprValue A, ExprValue B) {
if (uint64_t BV = B.getValue())
return A.getValue() / BV;
error("division by zero");
return 0;
}
static ExprValue mod(ExprValue A, ExprValue B) {
if (uint64_t BV = B.getValue())
return A.getValue() % BV;
error("modulo by zero");
return 0;
}
static ExprValue bitAnd(ExprValue A, ExprValue B) {
moveAbsRight(A, B);
return {A.Sec, A.ForceAbsolute,
@@ -809,17 +796,31 @@ Expr ScriptParser::readExpr() {
return E;
}
static Expr combine(StringRef Op, Expr L, Expr R) {
Expr ScriptParser::combine(StringRef Op, Expr L, Expr R) {
if (Op == "+")
return [=] { return add(L(), R()); };
if (Op == "-")
return [=] { return sub(L(), R()); };
if (Op == "*")
return [=] { return L().getValue() * R().getValue(); };
if (Op == "/")
return [=] { return div(L(), R()); };
if (Op == "%")
return [=] { return mod(L(), R()); };
if (Op == "/") {
std::string Loc = getCurrentLocation();
return [=]() -> uint64_t {
if (uint64_t RV = R().getValue())
return L().getValue() / RV;
error(Loc + ": division by zero");
return (uint64_t)0;
};
}
if (Op == "%") {
std::string Loc = getCurrentLocation();
return [=]() -> uint64_t {
if (uint64_t RV = R().getValue())
return L().getValue() % RV;
error(Loc + ": modulo by zero");
return (uint64_t)0;
};
}
if (Op == "<<")
return [=] { return L().getValue() << R().getValue(); };
if (Op == ">>")