tint: const eval of faceForward builtin
Bug: tint:1581
Change-Id: Ia50b4ec4d494face5e7f438037a092cd1f839849
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/111840
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: Ben Clayton <bclayton@google.com>
Commit-Queue: Antonio Maiorano <amaiorano@google.com>
diff --git a/src/tint/intrinsics.def b/src/tint/intrinsics.def
index a148d4d..687b8e1 100644
--- a/src/tint/intrinsics.def
+++ b/src/tint/intrinsics.def
@@ -466,7 +466,7 @@
@const fn exp2<N: num, T: fa_f32_f16>(vec<N, T>) -> vec<N, T>
@const fn extractBits<T: iu32>(T, u32, u32) -> T
@const fn extractBits<N: num, T: iu32>(vec<N, T>, u32, u32) -> vec<N, T>
-fn faceForward<N: num, T: f32_f16>(vec<N, T>, vec<N, T>, vec<N, T>) -> vec<N, T>
+@const fn faceForward<N: num, T: fa_f32_f16>(vec<N, T>, vec<N, T>, vec<N, T>) -> vec<N, T>
@const fn firstLeadingBit<T: iu32>(T) -> T
@const fn firstLeadingBit<N: num, T: iu32>(vec<N, T>) -> vec<N, T>
@const fn firstTrailingBit<T: iu32>(T) -> T
diff --git a/src/tint/resolver/const_eval.cc b/src/tint/resolver/const_eval.cc
index 159aaf4..f1197ce 100644
--- a/src/tint/resolver/const_eval.cc
+++ b/src/tint/resolver/const_eval.cc
@@ -2367,6 +2367,25 @@
return TransformElements(builder, ty, transform, args[0]);
}
+ConstEval::Result ConstEval::faceForward(const sem::Type* ty,
+ utils::VectorRef<const sem::Constant*> args,
+ const Source& source) {
+ // Returns e1 if dot(e2, e3) is negative, and -e1 otherwise.
+ auto* e1 = args[0];
+ auto* e2 = args[1];
+ auto* e3 = args[2];
+ auto r = Dot(source, e2, e3);
+ if (!r) {
+ AddNote("when calculating faceForward", source);
+ return utils::Failure;
+ }
+ auto is_negative = [](auto v) { return v < 0; };
+ if (Dispatch_fa_f32_f16(is_negative, r.Get())) {
+ return e1;
+ }
+ return OpUnaryMinus(ty, utils::Vector{e1}, source);
+}
+
ConstEval::Result ConstEval::firstLeadingBit(const sem::Type* ty,
utils::VectorRef<const sem::Constant*> args,
const Source& source) {
diff --git a/src/tint/resolver/const_eval.h b/src/tint/resolver/const_eval.h
index 0c8ec6b..df1db17 100644
--- a/src/tint/resolver/const_eval.h
+++ b/src/tint/resolver/const_eval.h
@@ -602,6 +602,15 @@
utils::VectorRef<const sem::Constant*> args,
const Source& source);
+ /// faceForward builtin
+ /// @param ty the expression type
+ /// @param args the input arguments
+ /// @param source the source location
+ /// @return the result value, or null if the value cannot be calculated
+ Result faceForward(const sem::Type* ty,
+ utils::VectorRef<const sem::Constant*> args,
+ const Source& source);
+
/// firstLeadingBit builtin
/// @param ty the expression type
/// @param args the input arguments
diff --git a/src/tint/resolver/const_eval_builtin_test.cc b/src/tint/resolver/const_eval_builtin_test.cc
index dabe7d9..7c5d708 100644
--- a/src/tint/resolver/const_eval_builtin_test.cc
+++ b/src/tint/resolver/const_eval_builtin_test.cc
@@ -954,6 +954,88 @@
DeterminantCases<f16>()))));
template <typename T>
+std::vector<Case> FaceForwardCases() {
+ // Rotate v by degs around Z axis
+ auto rotate = [&](const Value& v, float degs) {
+ auto x = builder::As<T>(v.args[0]);
+ auto y = builder::As<T>(v.args[1]);
+ auto z = builder::As<T>(v.args[2]);
+ auto rads = T(degs) * kPi<T> / T(180);
+ auto x2 = T(x * std::cos(rads) - y * std::sin(rads));
+ auto y2 = T(x * std::sin(rads) + y * std::cos(rads));
+ return Vec(x2, y2, z);
+ };
+
+ // An arbitrary input vector and its negation, used for e1 args to FaceForward
+ auto pos_vec = Vec(T(1), T(2), T(3));
+ auto neg_vec = Vec(-T(1), -T(2), -T(3));
+
+ // An arbitrary vector in the xy plane, used for e2 and e3 args to FaceForward.
+ auto fwd_xy = Vec(T(1.23), T(4.56), T(0));
+
+ std::vector<Case> r = {
+ C({pos_vec, fwd_xy, rotate(fwd_xy, 85)}, neg_vec),
+ C({pos_vec, fwd_xy, rotate(fwd_xy, 85)}, neg_vec),
+ C({pos_vec, fwd_xy, rotate(fwd_xy, 95)}, pos_vec),
+ C({pos_vec, fwd_xy, rotate(fwd_xy, -95)}, pos_vec),
+ C({pos_vec, fwd_xy, rotate(fwd_xy, 180)}, pos_vec),
+
+ C({pos_vec, rotate(fwd_xy, 33), rotate(fwd_xy, 33 + 85)}, neg_vec),
+ C({pos_vec, rotate(fwd_xy, 33), rotate(fwd_xy, 33 - 85)}, neg_vec),
+ C({pos_vec, rotate(fwd_xy, 33), rotate(fwd_xy, 33 + 95)}, pos_vec),
+ C({pos_vec, rotate(fwd_xy, 33), rotate(fwd_xy, 33 - 95)}, pos_vec),
+ C({pos_vec, rotate(fwd_xy, 33), rotate(fwd_xy, 33 + 180)}, pos_vec),
+
+ C({pos_vec, rotate(fwd_xy, 234), rotate(fwd_xy, 234 + 85)}, neg_vec),
+ C({pos_vec, rotate(fwd_xy, 234), rotate(fwd_xy, 234 - 85)}, neg_vec),
+ C({pos_vec, rotate(fwd_xy, 234), rotate(fwd_xy, 234 + 95)}, pos_vec),
+ C({pos_vec, rotate(fwd_xy, 234), rotate(fwd_xy, 234 - 95)}, pos_vec),
+ C({pos_vec, rotate(fwd_xy, 234), rotate(fwd_xy, 234 + 180)}, pos_vec),
+
+ // Same, but swap input and result vectors
+ C({neg_vec, fwd_xy, rotate(fwd_xy, 85)}, pos_vec),
+ C({neg_vec, fwd_xy, rotate(fwd_xy, 85)}, pos_vec),
+ C({neg_vec, fwd_xy, rotate(fwd_xy, 95)}, neg_vec),
+ C({neg_vec, fwd_xy, rotate(fwd_xy, -95)}, neg_vec),
+ C({neg_vec, fwd_xy, rotate(fwd_xy, 180)}, neg_vec),
+
+ C({neg_vec, rotate(fwd_xy, 33), rotate(fwd_xy, 33 + 85)}, pos_vec),
+ C({neg_vec, rotate(fwd_xy, 33), rotate(fwd_xy, 33 - 85)}, pos_vec),
+ C({neg_vec, rotate(fwd_xy, 33), rotate(fwd_xy, 33 + 95)}, neg_vec),
+ C({neg_vec, rotate(fwd_xy, 33), rotate(fwd_xy, 33 - 95)}, neg_vec),
+ C({neg_vec, rotate(fwd_xy, 33), rotate(fwd_xy, 33 + 180)}, neg_vec),
+
+ C({neg_vec, rotate(fwd_xy, 234), rotate(fwd_xy, 234 + 85)}, pos_vec),
+ C({neg_vec, rotate(fwd_xy, 234), rotate(fwd_xy, 234 - 85)}, pos_vec),
+ C({neg_vec, rotate(fwd_xy, 234), rotate(fwd_xy, 234 + 95)}, neg_vec),
+ C({neg_vec, rotate(fwd_xy, 234), rotate(fwd_xy, 234 - 95)}, neg_vec),
+ C({neg_vec, rotate(fwd_xy, 234), rotate(fwd_xy, 234 + 180)}, neg_vec),
+ };
+
+ auto error_msg = [](auto a, const char* op, auto b) {
+ return "12:34 error: " + OverflowErrorMessage(a, op, b) + R"(
+12:34 note: when calculating faceForward)";
+ };
+ ConcatInto( //
+ r, std::vector<Case>{
+ // Overflow the dot product operation
+ E({pos_vec, Vec(T::Highest(), T::Highest(), T(0)), Vec(T(1), T(1), T(0))},
+ error_msg(T::Highest(), "+", T::Highest())),
+ E({pos_vec, Vec(T::Lowest(), T::Lowest(), T(0)), Vec(T(1), T(1), T(0))},
+ error_msg(T::Lowest(), "+", T::Lowest())),
+ });
+
+ return r;
+}
+INSTANTIATE_TEST_SUITE_P( //
+ FaceForward,
+ ResolverConstEvalBuiltinTest,
+ testing::Combine(testing::Values(sem::BuiltinType::kFaceForward),
+ testing::ValuesIn(Concat(FaceForwardCases<AFloat>(), //
+ FaceForwardCases<f32>(), //
+ FaceForwardCases<f16>()))));
+
+template <typename T>
std::vector<Case> FirstLeadingBitCases() {
using B = BitValues<T>;
auto r = std::vector<Case>{
diff --git a/src/tint/resolver/intrinsic_table.inl b/src/tint/resolver/intrinsic_table.inl
index 9d77df3..e521a9c 100644
--- a/src/tint/resolver/intrinsic_table.inl
+++ b/src/tint/resolver/intrinsic_table.inl
@@ -13614,12 +13614,12 @@
/* num parameters */ 3,
/* num template types */ 1,
/* num template numbers */ 1,
- /* template types */ &kTemplateTypes[26],
+ /* template types */ &kTemplateTypes[23],
/* template numbers */ &kTemplateNumbers[4],
/* parameters */ &kParameters[459],
/* return matcher indices */ &kMatcherIndices[30],
/* flags */ OverloadFlags(OverloadFlag::kIsBuiltin, OverloadFlag::kSupportsVertexPipeline, OverloadFlag::kSupportsFragmentPipeline, OverloadFlag::kSupportsComputePipeline),
- /* const eval */ nullptr,
+ /* const eval */ &ConstEval::faceForward,
},
{
/* [442] */
@@ -14218,7 +14218,7 @@
},
{
/* [34] */
- /* fn faceForward<N : num, T : f32_f16>(vec<N, T>, vec<N, T>, vec<N, T>) -> vec<N, T> */
+ /* fn faceForward<N : num, T : fa_f32_f16>(vec<N, T>, vec<N, T>, vec<N, T>) -> vec<N, T> */
/* num overloads */ 1,
/* overloads */ &kOverloads[441],
},
diff --git a/src/tint/resolver/resolver_test_helper.h b/src/tint/resolver/resolver_test_helper.h
index cf17b61..d44c9d8 100644
--- a/src/tint/resolver/resolver_test_helper.h
+++ b/src/tint/resolver/resolver_test_helper.h
@@ -185,7 +185,7 @@
/// Returns current variant value in `s` cast to type `T`
template <typename T>
-T As(Scalar& s) {
+T As(const Scalar& s) {
return std::visit([](auto&& v) { return static_cast<T>(v); }, s);
}
