tint: optimize compile time for const_eval_*_test files

The reason for slow compile times is because the very large variants of
builder::Value<T>s combined with the many std::visits over these
variants result in many combinatorial instantiations of the visit
callbacks.

To address this, I added a polymorphic base class ValueBase to Value<T>,
and replaced most of the std::visit-based compile time code with runtime
virtual calls. For the two heaviest users of std::visit over the large
variants, compiles times dropped more than half (clang-10, debug):

const_eval_binary_op_test.cc: 19.079s to 7.736s
const_eval_unary_op_test.cc: 10.021s to 4.789s

Bug: tint:1711
Change-Id: Iba05e6ae1004ef0814250e2a8ea50aa2b26b85f2
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/105782
Reviewed-by: Ben Clayton <bclayton@google.com>
Kokoro: Kokoro <noreply+kokoro@google.com>
Commit-Queue: Antonio Maiorano <amaiorano@google.com>
This commit is contained in:
Antonio Maiorano 2022-10-17 16:11:02 +00:00 committed by Dawn LUCI CQ
parent 3fd42ae042
commit 29fb8f8eef
6 changed files with 198 additions and 163 deletions

View File

@ -54,47 +54,39 @@ TEST_P(ResolverConstEvalBinaryOpTest, Test) {
auto op = std::get<0>(GetParam());
auto& c = std::get<1>(GetParam());
std::visit(
[&](auto&& expected) {
using T = typename std::decay_t<decltype(expected)>::ElementType;
if constexpr (std::is_same_v<T, AInt> || std::is_same_v<T, AFloat>) {
if (c.overflow) {
// Overflow is not allowed for abstract types. This is tested separately.
return;
}
}
auto* expected = ToValueBase(c.expected);
if (expected->IsAbstract() && c.overflow) {
// Overflow is not allowed for abstract types. This is tested separately.
return;
}
auto* lhs_expr = std::visit([&](auto&& value) { return value.Expr(*this); }, c.lhs);
auto* rhs_expr = std::visit([&](auto&& value) { return value.Expr(*this); }, c.rhs);
auto* expr = create<ast::BinaryExpression>(op, lhs_expr, rhs_expr);
auto* lhs = ToValueBase(c.lhs);
auto* rhs = ToValueBase(c.rhs);
GlobalConst("C", expr);
auto* expected_expr = expected.Expr(*this);
GlobalConst("E", expected_expr);
ASSERT_TRUE(r()->Resolve()) << r()->error();
auto* lhs_expr = lhs->Expr(*this);
auto* rhs_expr = rhs->Expr(*this);
auto* expr = create<ast::BinaryExpression>(op, lhs_expr, rhs_expr);
GlobalConst("C", expr);
ASSERT_TRUE(r()->Resolve()) << r()->error();
auto* sem = Sem().Get(expr);
const sem::Constant* value = sem->ConstantValue();
ASSERT_NE(value, nullptr);
EXPECT_TYPE(value->Type(), sem->Type());
auto* sem = Sem().Get(expr);
const sem::Constant* value = sem->ConstantValue();
ASSERT_NE(value, nullptr);
EXPECT_TYPE(value->Type(), sem->Type());
auto* expected_sem = Sem().Get(expected_expr);
const sem::Constant* expected_value = expected_sem->ConstantValue();
ASSERT_NE(expected_value, nullptr);
EXPECT_TYPE(expected_value->Type(), expected_sem->Type());
ForEachElemPair(value, expected_value,
[&](const sem::Constant* a, const sem::Constant* b) {
EXPECT_EQ(a->As<T>(), b->As<T>());
if constexpr (IsIntegral<T>) {
// Check that the constant's integer doesn't contain unexpected
// data in the MSBs that are outside of the bit-width of T.
EXPECT_EQ(a->As<AInt>(), b->As<AInt>());
}
return HasFailure() ? Action::kStop : Action::kContinue;
});
},
c.expected);
auto values_flat = ScalarArgsFrom(value);
auto expected_values_flat = expected->Args();
ASSERT_EQ(values_flat.values.Length(), expected_values_flat.values.Length());
for (size_t i = 0; i < values_flat.values.Length(); ++i) {
auto& a = values_flat.values[i];
auto& b = expected_values_flat.values[i];
EXPECT_EQ(a, b);
if (expected->IsIntegral()) {
// Check that the constant's integer doesn't contain unexpected
// data in the MSBs that are outside of the bit-width of T.
EXPECT_EQ(builder::As<AInt>(a), builder::As<AInt>(b));
}
}
}
INSTANTIATE_TEST_SUITE_P(MixedAbstractArgs,
@ -658,21 +650,15 @@ using ResolverConstEvalBinaryOpTest_Overflow = ResolverTestWithParam<OverflowCas
TEST_P(ResolverConstEvalBinaryOpTest_Overflow, Test) {
Enable(ast::Extension::kF16);
auto& c = GetParam();
auto* lhs_expr = std::visit([&](auto&& value) { return value.Expr(*this); }, c.lhs);
auto* rhs_expr = std::visit([&](auto&& value) { return value.Expr(*this); }, c.rhs);
auto* lhs = ToValueBase(c.lhs);
auto* rhs = ToValueBase(c.rhs);
auto* lhs_expr = lhs->Expr(*this);
auto* rhs_expr = rhs->Expr(*this);
auto* expr = create<ast::BinaryExpression>(Source{{1, 1}}, c.op, lhs_expr, rhs_expr);
GlobalConst("C", expr);
ASSERT_FALSE(r()->Resolve());
std::string type_name = std::visit(
[&](auto&& value) {
using ValueType = std::decay_t<decltype(value)>;
return builder::FriendlyName<ValueType>();
},
c.lhs);
EXPECT_THAT(r()->error(), HasSubstr("1:1 error: '"));
EXPECT_THAT(r()->error(), HasSubstr("' cannot be represented as '" + type_name + "'"));
EXPECT_THAT(r()->error(), HasSubstr("' cannot be represented as '" + lhs->TypeName() + "'"));
}
INSTANTIATE_TEST_SUITE_P(
Test,
@ -854,10 +840,8 @@ TEST_F(ResolverConstEvalTest, BinaryAbstractShiftLeftByNegativeValue_Error) {
using ResolverConstEvalShiftLeftConcreteGeqBitWidthError =
ResolverTestWithParam<std::tuple<Types, Types>>;
TEST_P(ResolverConstEvalShiftLeftConcreteGeqBitWidthError, Test) {
auto* lhs_expr =
std::visit([&](auto&& value) { return value.Expr(*this); }, std::get<0>(GetParam()));
auto* rhs_expr =
std::visit([&](auto&& value) { return value.Expr(*this); }, std::get<1>(GetParam()));
auto* lhs_expr = ToValueBase(std::get<0>(GetParam()))->Expr(*this);
auto* rhs_expr = ToValueBase(std::get<1>(GetParam()))->Expr(*this);
GlobalConst("c", Shl(Source{{1, 1}}, lhs_expr, rhs_expr));
EXPECT_FALSE(r()->Resolve());
EXPECT_EQ(
@ -880,10 +864,8 @@ INSTANTIATE_TEST_SUITE_P(Test,
// AInt left shift results in sign change error
using ResolverConstEvalShiftLeftSignChangeError = ResolverTestWithParam<std::tuple<Types, Types>>;
TEST_P(ResolverConstEvalShiftLeftSignChangeError, Test) {
auto* lhs_expr =
std::visit([&](auto&& value) { return value.Expr(*this); }, std::get<0>(GetParam()));
auto* rhs_expr =
std::visit([&](auto&& value) { return value.Expr(*this); }, std::get<1>(GetParam()));
auto* lhs_expr = ToValueBase(std::get<0>(GetParam()))->Expr(*this);
auto* rhs_expr = ToValueBase(std::get<1>(GetParam()))->Expr(*this);
GlobalConst("c", Shl(Source{{1, 1}}, lhs_expr, rhs_expr));
EXPECT_FALSE(r()->Resolve());
EXPECT_EQ(r()->error(), "1:1 error: shift left operation results in sign change");

View File

@ -83,54 +83,57 @@ TEST_P(ResolverConstEvalBuiltinTest, Test) {
std::visit([&](auto&& v) { args.Push(v.Expr(*this)); }, a);
}
std::visit(
[&](auto&& expected) {
using T = typename std::decay_t<decltype(expected)>::ElementType;
auto* expr = Call(sem::str(builtin), std::move(args));
auto* expected = ToValueBase(c.expected);
auto* expr = Call(sem::str(builtin), std::move(args));
GlobalConst("C", expr);
auto* expected_expr = expected.Expr(*this);
GlobalConst("E", expected_expr);
GlobalConst("C", expr);
auto* expected_expr = expected->Expr(*this);
GlobalConst("E", expected_expr);
EXPECT_TRUE(r()->Resolve()) << r()->error();
EXPECT_TRUE(r()->Resolve()) << r()->error();
auto* sem = Sem().Get(expr);
const sem::Constant* value = sem->ConstantValue();
ASSERT_NE(value, nullptr);
EXPECT_TYPE(value->Type(), sem->Type());
auto* sem = Sem().Get(expr);
const sem::Constant* value = sem->ConstantValue();
ASSERT_NE(value, nullptr);
EXPECT_TYPE(value->Type(), sem->Type());
auto* expected_sem = Sem().Get(expected_expr);
const sem::Constant* expected_value = expected_sem->ConstantValue();
ASSERT_NE(expected_value, nullptr);
EXPECT_TYPE(expected_value->Type(), expected_sem->Type());
auto* expected_sem = Sem().Get(expected_expr);
const sem::Constant* expected_value = expected_sem->ConstantValue();
ASSERT_NE(expected_value, nullptr);
EXPECT_TYPE(expected_value->Type(), expected_sem->Type());
ForEachElemPair(value, expected_value,
[&](const sem::Constant* a, const sem::Constant* b) {
auto v = a->As<T>();
auto e = b->As<T>();
if constexpr (std::is_same_v<bool, T>) {
EXPECT_EQ(v, e);
} else if constexpr (IsFloatingPoint<T>) {
if (std::isnan(e)) {
EXPECT_TRUE(std::isnan(v));
} else {
auto vf = (c.expected_pos_or_neg ? Abs(v) : v);
if (c.float_compare) {
EXPECT_FLOAT_EQ(vf, e);
} else {
EXPECT_EQ(vf, e);
}
}
} else {
EXPECT_EQ((c.expected_pos_or_neg ? Abs(v) : v), e);
// Check that the constant's integer doesn't contain unexpected
// data in the MSBs that are outside of the bit-width of T.
EXPECT_EQ(a->As<AInt>(), b->As<AInt>());
}
return HasFailure() ? Action::kStop : Action::kContinue;
});
},
c.expected);
// @TODO(amaiorano): Rewrite using ScalarArgsFrom()
ForEachElemPair(value, expected_value, [&](const sem::Constant* a, const sem::Constant* b) {
std::visit(
[&](auto&& ct_expected) {
using T = typename std::decay_t<decltype(ct_expected)>::ElementType;
auto v = a->As<T>();
auto e = b->As<T>();
if constexpr (std::is_same_v<bool, T>) {
EXPECT_EQ(v, e);
} else if constexpr (IsFloatingPoint<T>) {
if (std::isnan(e)) {
EXPECT_TRUE(std::isnan(v));
} else {
auto vf = (c.expected_pos_or_neg ? Abs(v) : v);
if (c.float_compare) {
EXPECT_FLOAT_EQ(vf, e);
} else {
EXPECT_EQ(vf, e);
}
}
} else {
EXPECT_EQ((c.expected_pos_or_neg ? Abs(v) : v), e);
// Check that the constant's integer doesn't contain unexpected
// data in the MSBs that are outside of the bit-width of T.
EXPECT_EQ(a->As<AInt>(), b->As<AInt>());
}
},
c.expected);
return HasFailure() ? Action::kStop : Action::kContinue;
});
}
INSTANTIATE_TEST_SUITE_P( //

View File

@ -29,20 +29,7 @@ using Scalar = std::variant< //
builder::Value<bool>>;
static std::ostream& operator<<(std::ostream& o, const Scalar& scalar) {
std::visit(
[&](auto&& v) {
using ValueType = std::decay_t<decltype(v)>;
o << ValueType::DataType::Name() << "(";
for (auto& a : v.args.values) {
o << std::get<typename ValueType::ElementType>(a);
if (&a != &v.args.values.Back()) {
o << ", ";
}
}
o << ")";
},
scalar);
return o;
return ToValueBase(scalar)->Print(o);
}
enum class Kind {
@ -96,7 +83,7 @@ TEST_P(ResolverConstEvalConvTest, Test) {
const auto& type = std::get<1>(GetParam()).type;
const auto unrepresentable = std::get<1>(GetParam()).unrepresentable;
auto* input_val = std::visit([&](auto val) { return val.Expr(*this); }, input);
auto* input_val = ToValueBase(input)->Expr(*this);
auto* expr = Construct(type.ast(*this), input_val);
if (kind == Kind::kVector) {
expr = Construct(ty.vec(nullptr, 3), expr);
@ -120,7 +107,7 @@ TEST_P(ResolverConstEvalConvTest, Test) {
ASSERT_NE(sem->ConstantValue(), nullptr);
EXPECT_TYPE(sem->ConstantValue()->Type(), target_sem_ty);
auto expected_values = std::visit([&](auto&& val) { return val.args; }, expected);
auto expected_values = ToValueBase(expected)->Args();
if (kind == Kind::kVector) {
expected_values.values.Push(expected_values.values[0]);
expected_values.values.Push(expected_values.values[0]);

View File

@ -41,6 +41,8 @@ inline const auto k3PiOver4 = T(UnwrapNumber<T>(2.356194490192344928846));
inline void CollectScalarArgs(const sem::Constant* c, builder::ScalarArgs& args) {
Switch(
c->Type(), //
[&](const sem::AbstractInt*) { args.values.Push(c->As<AInt>()); },
[&](const sem::AbstractFloat*) { args.values.Push(c->As<AFloat>()); },
[&](const sem::Bool*) { args.values.Push(c->As<bool>()); },
[&](const sem::I32*) { args.values.Push(c->As<i32>()); },
[&](const sem::U32*) { args.values.Push(c->As<u32>()); },
@ -136,6 +138,7 @@ using builder::IsValue;
using builder::Mat;
using builder::Val;
using builder::Value;
using builder::ValueBase;
using builder::Vec;
using Types = std::variant< //
@ -188,21 +191,18 @@ using Types = std::variant< //
//
>;
/// Returns the current Value<T> in the `types` variant as a `ValueBase` pointer to use the
/// polymorphic API. This trades longer compile times using std::variant for longer runtime via
/// virtual function calls.
template <typename ValueVariant>
inline const ValueBase* ToValueBase(const ValueVariant& types) {
return std::visit(
[](auto&& t) -> const ValueBase* { return static_cast<const ValueBase*>(&t); }, types);
}
/// Prints Types to ostream
inline std::ostream& operator<<(std::ostream& o, const Types& types) {
std::visit(
[&](auto&& v) {
using ValueType = std::decay_t<decltype(v)>;
o << ValueType::DataType::Name() << "(";
for (auto& a : v.args.values) {
o << std::get<typename ValueType::ElementType>(a);
if (&a != &v.args.values.Back()) {
o << ", ";
}
}
o << ")";
},
types);
return o;
return ToValueBase(types)->Print(o);
}
// Calls `f` on deepest elements of both `a` and `b`. If function returns Action::kStop, it stops

View File

@ -51,40 +51,34 @@ TEST_P(ResolverConstEvalUnaryOpTest, Test) {
auto op = std::get<0>(GetParam());
auto& c = std::get<1>(GetParam());
std::visit(
[&](auto&& expected) {
using T = typename std::decay_t<decltype(expected)>::ElementType;
auto* input_expr = std::visit([&](auto&& value) { return value.Expr(*this); }, c.input);
auto* expr = create<ast::UnaryOpExpression>(op, input_expr);
auto* expected = ToValueBase(c.expected);
auto* input = ToValueBase(c.input);
GlobalConst("C", expr);
auto* expected_expr = expected.Expr(*this);
GlobalConst("E", expected_expr);
ASSERT_TRUE(r()->Resolve()) << r()->error();
auto* input_expr = input->Expr(*this);
auto* expr = create<ast::UnaryOpExpression>(op, input_expr);
auto* sem = Sem().Get(expr);
const sem::Constant* value = sem->ConstantValue();
ASSERT_NE(value, nullptr);
EXPECT_TYPE(value->Type(), sem->Type());
GlobalConst("C", expr);
ASSERT_TRUE(r()->Resolve()) << r()->error();
auto* expected_sem = Sem().Get(expected_expr);
const sem::Constant* expected_value = expected_sem->ConstantValue();
ASSERT_NE(expected_value, nullptr);
EXPECT_TYPE(expected_value->Type(), expected_sem->Type());
auto* sem = Sem().Get(expr);
const sem::Constant* value = sem->ConstantValue();
ASSERT_NE(value, nullptr);
EXPECT_TYPE(value->Type(), sem->Type());
ForEachElemPair(value, expected_value,
[&](const sem::Constant* a, const sem::Constant* b) {
EXPECT_EQ(a->As<T>(), b->As<T>());
if constexpr (IsIntegral<T>) {
// Check that the constant's integer doesn't contain unexpected
// data in the MSBs that are outside of the bit-width of T.
EXPECT_EQ(a->As<AInt>(), b->As<AInt>());
}
return HasFailure() ? Action::kStop : Action::kContinue;
});
},
c.expected);
auto values_flat = ScalarArgsFrom(value);
auto expected_values_flat = expected->Args();
ASSERT_EQ(values_flat.values.Length(), expected_values_flat.values.Length());
for (size_t i = 0; i < values_flat.values.Length(); ++i) {
auto& a = values_flat.values[i];
auto& b = expected_values_flat.values[i];
EXPECT_EQ(a, b);
if (expected->IsIntegral()) {
// Check that the constant's integer doesn't contain unexpected
// data in the MSBs that are outside of the bit-width of T.
EXPECT_EQ(builder::As<AInt>(a), builder::As<AInt>(b));
}
}
}
INSTANTIATE_TEST_SUITE_P(Complement,
ResolverConstEvalUnaryOpTest,

View File

@ -206,6 +206,12 @@ struct ScalarArgs {
utils::Vector<Storage, 16> values;
};
/// Returns current variant value in `s` cast to type `T`
template <typename T>
T As(ScalarArgs::Storage& s) {
return std::visit([](auto&& v) { return static_cast<T>(v); }, s);
}
/// @param o the std::ostream to write to
/// @param args the ScalarArgs
/// @return the std::ostream so calls can be chained
@ -750,10 +756,45 @@ constexpr CreatePtrs CreatePtrsFor() {
DataType<T>::Name};
}
/// Base class for Value<T>
struct ValueBase {
/// Constructor
ValueBase() = default;
/// Destructor
virtual ~ValueBase() = default;
/// Move constructor
ValueBase(ValueBase&&) = default;
/// Copy constructor
ValueBase(const ValueBase&) = default;
/// Copy assignment operator
/// @returns this instance
ValueBase& operator=(const ValueBase&) = default;
/// Creates an `ast::Expression` for the type T passing in previously stored args
/// @param b the ProgramBuilder
/// @returns an expression node
virtual const ast::Expression* Expr(ProgramBuilder& b) const = 0;
/// @returns args used to create expression via `Expr`
virtual const ScalarArgs& Args() const = 0;
/// @returns true if element type is abstract
virtual bool IsAbstract() const = 0;
/// @returns true if element type is an integral
virtual bool IsIntegral() const = 0;
/// @returns element type name
virtual std::string TypeName() const = 0;
/// Prints this value to the output stream
/// @param o the output stream
/// @returns input argument `o`
virtual std::ostream& Print(std::ostream& o) const = 0;
};
/// Value<T> is an instance of a value of type DataType<T>. Useful for storing values to create
/// expressions with.
template <typename T>
struct Value {
struct Value : ValueBase {
/// Constructor
/// @param a the scalar args
explicit Value(ScalarArgs a) : args(std::move(a)) {}
/// Alias to T
using Type = T;
/// Alias to DataType<T>
@ -764,15 +805,43 @@ struct Value {
/// Creates a Value<T> with `args`
/// @param args the args that will be passed to the expression
/// @returns a Value<T>
static Value Create(ScalarArgs args) { return Value{CreatePtrsFor<T>(), std::move(args)}; }
static Value Create(ScalarArgs args) { return Value{std::move(args)}; }
/// Creates an `ast::Expression` for the type T passing in previously stored args
/// @param b the ProgramBuilder
/// @returns an expression node
const ast::Expression* Expr(ProgramBuilder& b) const { return (*create.expr)(b, args); }
const ast::Expression* Expr(ProgramBuilder& b) const override {
auto create = CreatePtrsFor<T>();
return (*create.expr)(b, args);
}
/// @returns args used to create expression via `Expr`
const ScalarArgs& Args() const override { return args; }
/// @returns true if element type is abstract
bool IsAbstract() const override { return tint::IsAbstract<ElementType>; }
/// @returns true if element type is an integral
bool IsIntegral() const override { return tint::IsIntegral<ElementType>; }
/// @returns element type name
std::string TypeName() const override { return tint::FriendlyName<ElementType>(); }
/// Prints this value to the output stream
/// @param o the output stream
/// @returns input argument `o`
std::ostream& Print(std::ostream& o) const override {
o << TypeName() << "(";
for (auto& a : args.values) {
o << std::get<ElementType>(a);
if (&a != &args.values.Back()) {
o << ", ";
}
}
o << ")";
return o;
}
/// functions to create values / types of the value
CreatePtrs create;
/// args to create expression with
ScalarArgs args;
};