| // Copyright 2022 The Dawn & Tint Authors |
| // |
| // Redistribution and use in source and binary forms, with or without |
| // modification, are permitted provided that the following conditions are met: |
| // |
| // 1. Redistributions of source code must retain the above copyright notice, this |
| // list of conditions and the following disclaimer. |
| // |
| // 2. Redistributions in binary form must reproduce the above copyright notice, |
| // this list of conditions and the following disclaimer in the documentation |
| // and/or other materials provided with the distribution. |
| // |
| // 3. Neither the name of the copyright holder nor the names of its |
| // contributors may be used to endorse or promote products derived from |
| // this software without specific prior written permission. |
| // |
| // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" |
| // AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| // IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE |
| // DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE |
| // FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| // DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR |
| // SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER |
| // CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, |
| // OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| |
| #include "src/tint/lang/wgsl/ast/transform/builtin_polyfill.h" |
| |
| #include <algorithm> |
| #include <tuple> |
| #include <unordered_map> |
| #include <utility> |
| |
| #include "src/tint/lang/core/type/storage_texture.h" |
| #include "src/tint/lang/core/type/texture_dimension.h" |
| #include "src/tint/lang/wgsl/program/clone_context.h" |
| #include "src/tint/lang/wgsl/program/program_builder.h" |
| #include "src/tint/lang/wgsl/resolver/resolve.h" |
| #include "src/tint/lang/wgsl/sem/builtin_fn.h" |
| #include "src/tint/lang/wgsl/sem/call.h" |
| #include "src/tint/lang/wgsl/sem/type_expression.h" |
| #include "src/tint/lang/wgsl/sem/value_conversion.h" |
| #include "src/tint/utils/containers/map.h" |
| #include "src/tint/utils/rtti/switch.h" |
| |
| using namespace tint::core::fluent_types; // NOLINT |
| using namespace tint::core::number_suffixes; // NOLINT |
| |
| TINT_INSTANTIATE_TYPEINFO(tint::ast::transform::BuiltinPolyfill); |
| TINT_INSTANTIATE_TYPEINFO(tint::ast::transform::BuiltinPolyfill::Config); |
| |
| namespace tint::ast::transform { |
| |
| /// BinaryOpSignature is tuple of a binary op, LHS type and RHS type |
| using BinaryOpSignature = |
| std::tuple<core::BinaryOp, const core::type::Type*, const core::type::Type*>; |
| |
| /// PIMPL state for the transform |
| struct BuiltinPolyfill::State { |
| /// Constructor |
| /// @param program the source program |
| /// @param config the transform config |
| State(const Program& program, const Config& config) : src(program), cfg(config) {} |
| |
| /// Runs the transform |
| /// @returns the new program or SkipTransform if the transform is not required |
| Transform::ApplyResult Run() { |
| for (auto* node : src.ASTNodes().Objects()) { |
| Switch( |
| node, // |
| [&](const CallExpression* expr) { Call(expr); }, |
| [&](const BinaryExpression* bin_op) { |
| if (auto* s = src.Sem().Get(bin_op); |
| !s || s->Stage() == core::EvaluationStage::kConstant || |
| s->Stage() == core::EvaluationStage::kNotEvaluated) { |
| return; // Don't polyfill @const expressions |
| } |
| switch (bin_op->op) { |
| case core::BinaryOp::kShiftLeft: |
| case core::BinaryOp::kShiftRight: { |
| if (cfg.builtins.bitshift_modulo) { |
| ctx.Replace(bin_op, |
| [this, bin_op] { return BitshiftModulo(bin_op); }); |
| made_changes = true; |
| } |
| break; |
| } |
| case core::BinaryOp::kDivide: { |
| if (cfg.builtins.int_div_mod) { |
| auto* lhs_ty = src.TypeOf(bin_op->lhs)->UnwrapRef(); |
| if (lhs_ty->is_integer_scalar_or_vector()) { |
| ctx.Replace(bin_op, |
| [this, bin_op] { return IntDivMod(bin_op); }); |
| made_changes = true; |
| } |
| } |
| break; |
| } |
| case core::BinaryOp::kModulo: { |
| if (cfg.builtins.int_div_mod) { |
| auto* lhs_ty = src.TypeOf(bin_op->lhs)->UnwrapRef(); |
| if (lhs_ty->is_integer_scalar_or_vector()) { |
| ctx.Replace(bin_op, |
| [this, bin_op] { return IntDivMod(bin_op); }); |
| made_changes = true; |
| } |
| } |
| if (cfg.builtins.precise_float_mod) { |
| auto* lhs_ty = src.TypeOf(bin_op->lhs)->UnwrapRef(); |
| if (lhs_ty->is_float_scalar_or_vector()) { |
| ctx.Replace(bin_op, |
| [this, bin_op] { return PreciseFloatMod(bin_op); }); |
| made_changes = true; |
| } |
| } |
| break; |
| } |
| default: |
| break; |
| } |
| }, |
| [&](const Expression* expr) { |
| if (cfg.builtins.bgra8unorm) { |
| if (auto* ty_expr = src.Sem().Get<sem::TypeExpression>(expr)) { |
| if (auto* tex = ty_expr->Type()->As<core::type::StorageTexture>()) { |
| if (tex->texel_format() == core::TexelFormat::kBgra8Unorm) { |
| ctx.Replace(expr, [this, tex] { |
| return ctx.dst->Expr(ctx.dst->ty.storage_texture( |
| tex->dim(), core::TexelFormat::kRgba8Unorm, |
| tex->access())); |
| }); |
| made_changes = true; |
| } |
| } |
| } |
| } |
| }); |
| } |
| |
| if (!made_changes) { |
| return SkipTransform; |
| } |
| |
| ctx.Clone(); |
| return resolver::Resolve(b); |
| } |
| |
| private: |
| /// The source program |
| const Program& src; |
| /// The transform config |
| const Config& cfg; |
| /// The destination program builder |
| ProgramBuilder b; |
| /// The clone context |
| program::CloneContext ctx{&b, &src}; |
| /// The source clone context |
| const sem::Info& sem = src.Sem(); |
| /// Polyfill functions for binary operators. |
| Hashmap<BinaryOpSignature, Symbol, 8> binary_op_polyfills; |
| /// Polyfill builtins. |
| Hashmap<const sem::BuiltinFn*, Symbol, 8> builtin_polyfills; |
| /// Polyfill f32 conversion to i32 or u32 (or vectors of) |
| Hashmap<const core::type::Type*, Symbol, 2> f32_conv_polyfills; |
| /// True if the transform has made changes (i.e. the program needs cloning) |
| bool made_changes = false; |
| |
| //////////////////////////////////////////////////////////////////////////// |
| // Function polyfills |
| //////////////////////////////////////////////////////////////////////////// |
| |
| /// Builds the polyfill function for the `acosh` builtin |
| /// @param ty the parameter and return type for the function |
| /// @return the polyfill function name |
| Symbol acosh(const core::type::Type* ty) { |
| auto name = b.Symbols().New("tint_acosh"); |
| uint32_t width = WidthOf(ty); |
| |
| auto V = [&](AFloat value) -> const Expression* { |
| const Expression* expr = b.Expr(value); |
| if (width == 1) { |
| return expr; |
| } |
| return b.Call(T(ty), expr); |
| }; |
| |
| tint::Vector<const Statement*, 4> body; |
| switch (cfg.builtins.acosh) { |
| case Level::kFull: |
| // return log(x + sqrt(x*x - 1)); |
| body.Push(b.Return( |
| b.Call("log", b.Add("x", b.Call("sqrt", b.Sub(b.Mul("x", "x"), 1_a)))))); |
| break; |
| case Level::kRangeCheck: { |
| // return select(acosh(x), 0, x < 1); |
| body.Push(b.Return( |
| b.Call("select", b.Call("acosh", "x"), V(0.0_a), b.LessThan("x", V(1.0_a))))); |
| break; |
| } |
| default: |
| TINT_ICE() << "unhandled polyfill level: " << static_cast<int>(cfg.builtins.acosh); |
| return {}; |
| } |
| |
| b.Func(name, tint::Vector{b.Param("x", T(ty))}, T(ty), body); |
| |
| return name; |
| } |
| |
| /// Builds the polyfill function for the `asinh` builtin |
| /// @param ty the parameter and return type for the function |
| /// @return the polyfill function name |
| Symbol asinh(const core::type::Type* ty) { |
| auto name = b.Symbols().New("tint_sinh"); |
| |
| // return log(x + sqrt(x*x + 1)); |
| b.Func(name, tint::Vector{b.Param("x", T(ty))}, T(ty), |
| tint::Vector{ |
| b.Return(b.Call("log", b.Add("x", b.Call("sqrt", b.Add(b.Mul("x", "x"), 1_a))))), |
| }); |
| |
| return name; |
| } |
| |
| /// Builds the polyfill function for the `atanh` builtin |
| /// @param ty the parameter and return type for the function |
| /// @return the polyfill function name |
| Symbol atanh(const core::type::Type* ty) { |
| auto name = b.Symbols().New("tint_atanh"); |
| uint32_t width = WidthOf(ty); |
| |
| auto V = [&](AFloat value) -> const Expression* { |
| const Expression* expr = b.Expr(value); |
| if (width == 1) { |
| return expr; |
| } |
| return b.Call(T(ty), expr); |
| }; |
| |
| tint::Vector<const Statement*, 1> body; |
| switch (cfg.builtins.atanh) { |
| case Level::kFull: |
| // return log((1+x) / (1-x)) * 0.5 |
| body.Push( |
| b.Return(b.Mul(b.Call("log", b.Div(b.Add(1_a, "x"), b.Sub(1_a, "x"))), 0.5_a))); |
| break; |
| case Level::kRangeCheck: |
| // return select(atanh(x), 0, x >= 1); |
| body.Push(b.Return(b.Call("select", b.Call("atanh", "x"), V(0.0_a), |
| b.GreaterThanEqual("x", V(1.0_a))))); |
| break; |
| default: |
| TINT_ICE() << "unhandled polyfill level: " << static_cast<int>(cfg.builtins.acosh); |
| return {}; |
| } |
| |
| b.Func(name, tint::Vector{b.Param("x", T(ty))}, T(ty), body); |
| |
| return name; |
| } |
| |
| /// Builds the polyfill function for the `clamp` builtin when called with integer arguments |
| /// (scalar or vector) |
| /// @param ty the parameter and return type for the function |
| /// @return the polyfill function name |
| Symbol clampInteger(const core::type::Type* ty) { |
| auto name = b.Symbols().New("tint_clamp"); |
| |
| b.Func(name, |
| tint::Vector{ |
| b.Param("e", T(ty)), |
| b.Param("low", T(ty)), |
| b.Param("high", T(ty)), |
| }, |
| T(ty), |
| tint::Vector{ |
| // return min(max(e, low), high); |
| b.Return(b.Call("min", b.Call("max", "e", "low"), "high")), |
| }); |
| return name; |
| } |
| |
| /// Builds the polyfill function for the `countLeadingZeros` builtin |
| /// @param ty the parameter and return type for the function |
| /// @return the polyfill function name |
| Symbol countLeadingZeros(const core::type::Type* ty) { |
| auto name = b.Symbols().New("tint_count_leading_zeros"); |
| uint32_t width = WidthOf(ty); |
| |
| // Returns either u32 or vecN<u32> |
| auto U = [&] { |
| if (width == 1) { |
| return b.ty.u32(); |
| } |
| return b.ty.vec<u32>(width); |
| }; |
| auto V = [&](uint32_t value) -> const Expression* { |
| return ScalarOrVector(width, u32(value)); |
| }; |
| b.Func( |
| name, |
| tint::Vector{ |
| b.Param("v", T(ty)), |
| }, |
| T(ty), |
| tint::Vector{ |
| // var x = U(v); |
| b.Decl(b.Var("x", b.Call(U(), b.Expr("v")))), |
| // let b16 = select(0, 16, x <= 0x0000ffff); |
| b.Decl(b.Let("b16", |
| b.Call("select", V(0), V(16), b.LessThanEqual("x", V(0x0000ffff))))), |
| // x = x << b16; |
| b.Assign("x", b.Shl("x", "b16")), |
| // let b8 = select(0, 8, x <= 0x00ffffff); |
| b.Decl( |
| b.Let("b8", b.Call("select", V(0), V(8), b.LessThanEqual("x", V(0x00ffffff))))), |
| // x = x << b8; |
| b.Assign("x", b.Shl("x", "b8")), |
| // let b4 = select(0, 4, x <= 0x0fffffff); |
| b.Decl( |
| b.Let("b4", b.Call("select", V(0), V(4), b.LessThanEqual("x", V(0x0fffffff))))), |
| // x = x << b4; |
| b.Assign("x", b.Shl("x", "b4")), |
| // let b2 = select(0, 2, x <= 0x3fffffff); |
| b.Decl( |
| b.Let("b2", b.Call("select", V(0), V(2), b.LessThanEqual("x", V(0x3fffffff))))), |
| // x = x << b2; |
| b.Assign("x", b.Shl("x", "b2")), |
| // let b1 = select(0, 1, x <= 0x7fffffff); |
| b.Decl( |
| b.Let("b1", b.Call("select", V(0), V(1), b.LessThanEqual("x", V(0x7fffffff))))), |
| // let is_zero = select(0, 1, x == 0); |
| b.Decl(b.Let("is_zero", b.Call("select", V(0), V(1), b.Equal("x", V(0))))), |
| // return R((b16 | b8 | b4 | b2 | b1) + zero); |
| b.Return(b.Call(T(ty), b.Add(b.Or(b.Or(b.Or(b.Or("b16", "b8"), "b4"), "b2"), "b1"), |
| "is_zero"))), |
| }); |
| return name; |
| } |
| |
| /// Builds the polyfill function for the `countTrailingZeros` builtin |
| /// @param ty the parameter and return type for the function |
| /// @return the polyfill function name |
| Symbol countTrailingZeros(const core::type::Type* ty) { |
| auto name = b.Symbols().New("tint_count_trailing_zeros"); |
| uint32_t width = WidthOf(ty); |
| |
| // Returns either u32 or vecN<u32> |
| auto U = [&] { |
| if (width == 1) { |
| return b.ty.u32(); |
| } |
| return b.ty.vec<u32>(width); |
| }; |
| auto V = [&](uint32_t value) -> const Expression* { |
| return ScalarOrVector(width, u32(value)); |
| }; |
| auto B = [&](const Expression* value) -> const Expression* { |
| if (width == 1) { |
| return b.Call<bool>(value); |
| } |
| return b.Call(b.ty.vec<bool>(width), value); |
| }; |
| b.Func( |
| name, |
| tint::Vector{ |
| b.Param("v", T(ty)), |
| }, |
| T(ty), |
| tint::Vector{ |
| // var x = U(v); |
| b.Decl(b.Var("x", b.Call(U(), b.Expr("v")))), |
| // let b16 = select(16, 0, bool(x & 0x0000ffff)); |
| b.Decl(b.Let("b16", b.Call("select", V(16), V(0), B(b.And("x", V(0x0000ffff)))))), |
| // x = x >> b16; |
| b.Assign("x", b.Shr("x", "b16")), |
| // let b8 = select(8, 0, bool(x & 0x000000ff)); |
| b.Decl(b.Let("b8", b.Call("select", V(8), V(0), B(b.And("x", V(0x000000ff)))))), |
| // x = x >> b8; |
| b.Assign("x", b.Shr("x", "b8")), |
| // let b4 = select(4, 0, bool(x & 0x0000000f)); |
| b.Decl(b.Let("b4", b.Call("select", V(4), V(0), B(b.And("x", V(0x0000000f)))))), |
| // x = x >> b4; |
| b.Assign("x", b.Shr("x", "b4")), |
| // let b2 = select(2, 0, bool(x & 0x00000003)); |
| b.Decl(b.Let("b2", b.Call("select", V(2), V(0), B(b.And("x", V(0x00000003)))))), |
| // x = x >> b2; |
| b.Assign("x", b.Shr("x", "b2")), |
| // let b1 = select(1, 0, bool(x & 0x00000001)); |
| b.Decl(b.Let("b1", b.Call("select", V(1), V(0), B(b.And("x", V(0x00000001)))))), |
| // let is_zero = select(0, 1, x == 0); |
| b.Decl(b.Let("is_zero", b.Call("select", V(0), V(1), b.Equal("x", V(0))))), |
| // return R((b16 | b8 | b4 | b2 | b1) + zero); |
| b.Return(b.Call(T(ty), b.Add(b.Or(b.Or(b.Or(b.Or("b16", "b8"), "b4"), "b2"), "b1"), |
| "is_zero"))), |
| }); |
| return name; |
| } |
| |
| /// Builds the polyfill function for the `extractBits` builtin |
| /// @param ty the parameter and return type for the function |
| /// @return the polyfill function name |
| Symbol extractBits(const core::type::Type* ty) { |
| auto name = b.Symbols().New("tint_extract_bits"); |
| uint32_t width = WidthOf(ty); |
| |
| constexpr uint32_t W = 32u; // 32-bit |
| |
| auto vecN_u32 = [&](const Expression* value) -> const Expression* { |
| if (width == 1) { |
| return value; |
| } |
| return b.Call(b.ty.vec<u32>(width), value); |
| }; |
| |
| tint::Vector<const Statement*, 8> body{ |
| b.Decl(b.Let("s", b.Call("min", "offset", u32(W)))), |
| b.Decl(b.Let("e", b.Call("min", u32(W), b.Add("s", "count")))), |
| }; |
| |
| switch (cfg.builtins.extract_bits) { |
| case Level::kFull: |
| body.Push(b.Decl(b.Let("shl", b.Sub(u32(W), "e")))); |
| body.Push(b.Decl(b.Let("shr", b.Add("shl", "s")))); |
| // Here we don't want the shl and shr modulos the rhs, so handle the `rhs >= 32u` |
| // cases using `select`. In order to handle the signed shr `lhs >> rhs` corrently, |
| // use `(lhs >> 31u) >> 1u` if `rhs >= 32u`. |
| body.Push(b.Decl(b.Let("shl_result", b.Call("select", b.Call(T(ty)), |
| b.Shl("v", vecN_u32(b.Expr("shl"))), |
| b.LessThan("shl", 32_u))))); |
| body.Push(b.Return(b.Call( |
| "select", |
| b.Shr(b.Shr("shl_result", vecN_u32(b.Expr(31_u))), vecN_u32(b.Expr(1_u))), |
| b.Shr("shl_result", vecN_u32(b.Expr("shr"))), b.LessThan("shr", 32_u)) |
| |
| )); |
| break; |
| case Level::kClampParameters: |
| body.Push(b.Return(b.Call("extractBits", "v", "s", b.Sub("e", "s")))); |
| break; |
| default: |
| TINT_ICE() << "unhandled polyfill level: " |
| << static_cast<int>(cfg.builtins.extract_bits); |
| return {}; |
| } |
| |
| b.Func(name, |
| tint::Vector{ |
| b.Param("v", T(ty)), |
| b.Param("offset", b.ty.u32()), |
| b.Param("count", b.ty.u32()), |
| }, |
| T(ty), std::move(body)); |
| |
| return name; |
| } |
| |
| /// Builds the polyfill function for the `firstLeadingBit` builtin |
| /// @param ty the parameter and return type for the function |
| /// @return the polyfill function name |
| Symbol firstLeadingBit(const core::type::Type* ty) { |
| auto name = b.Symbols().New("tint_first_leading_bit"); |
| uint32_t width = WidthOf(ty); |
| |
| // Returns either u32 or vecN<u32> |
| auto U = [&] { |
| if (width == 1) { |
| return b.ty.u32(); |
| } |
| return b.ty.vec<u32>(width); |
| }; |
| auto V = [&](uint32_t value) -> const Expression* { |
| return ScalarOrVector(width, u32(value)); |
| }; |
| auto B = [&](const Expression* value) -> const Expression* { |
| if (width == 1) { |
| return b.Call<bool>(value); |
| } |
| return b.Call(b.ty.vec<bool>(width), value); |
| }; |
| |
| const Expression* x = nullptr; |
| if (ty->is_unsigned_integer_scalar_or_vector()) { |
| x = b.Expr("v"); |
| } else { |
| // If ty is signed, then the value is inverted if the sign is negative |
| x = b.Call("select", // |
| b.Call(U(), "v"), // |
| b.Call(U(), b.Complement("v")), // |
| b.LessThan("v", ScalarOrVector(width, 0_i))); |
| } |
| |
| b.Func( |
| name, |
| tint::Vector{ |
| b.Param("v", T(ty)), |
| }, |
| T(ty), |
| tint::Vector{ |
| // var x = v; (unsigned) |
| // var x = select(U(v), ~U(v), v < 0); (signed) |
| b.Decl(b.Var("x", x)), |
| // let b16 = select(0, 16, bool(x & 0xffff0000)); |
| b.Decl(b.Let("b16", b.Call("select", V(0), V(16), B(b.And("x", V(0xffff0000)))))), |
| // x = x >> b16; |
| b.Assign("x", b.Shr("x", "b16")), |
| // let b8 = select(0, 8, bool(x & 0x0000ff00)); |
| b.Decl(b.Let("b8", b.Call("select", V(0), V(8), B(b.And("x", V(0x0000ff00)))))), |
| // x = x >> b8; |
| b.Assign("x", b.Shr("x", "b8")), |
| // let b4 = select(0, 4, bool(x & 0x000000f0)); |
| b.Decl(b.Let("b4", b.Call("select", V(0), V(4), B(b.And("x", V(0x000000f0)))))), |
| // x = x >> b4; |
| b.Assign("x", b.Shr("x", "b4")), |
| // let b2 = select(0, 2, bool(x & 0x0000000c)); |
| b.Decl(b.Let("b2", b.Call("select", V(0), V(2), B(b.And("x", V(0x0000000c)))))), |
| // x = x >> b2; |
| b.Assign("x", b.Shr("x", "b2")), |
| // let b1 = select(0, 1, bool(x & 0x00000002)); |
| b.Decl(b.Let("b1", b.Call("select", V(0), V(1), B(b.And("x", V(0x00000002)))))), |
| // let is_zero = select(0, 0xffffffff, x == 0); |
| b.Decl(b.Let("is_zero", b.Call("select", V(0), V(0xffffffff), b.Equal("x", V(0))))), |
| // return R(b16 | b8 | b4 | b2 | b1 | zero); |
| b.Return(b.Call( |
| T(ty), b.Or(b.Or(b.Or(b.Or(b.Or("b16", "b8"), "b4"), "b2"), "b1"), "is_zero"))), |
| }); |
| return name; |
| } |
| |
| /// Builds the polyfill function for the `firstTrailingBit` builtin |
| /// @param ty the parameter and return type for the function |
| /// @return the polyfill function name |
| Symbol firstTrailingBit(const core::type::Type* ty) { |
| auto name = b.Symbols().New("tint_first_trailing_bit"); |
| uint32_t width = WidthOf(ty); |
| |
| // Returns either u32 or vecN<u32> |
| auto U = [&] { |
| if (width == 1) { |
| return b.ty.u32(); |
| } |
| return b.ty.vec<u32>(width); |
| }; |
| auto V = [&](uint32_t value) -> const Expression* { |
| return ScalarOrVector(width, u32(value)); |
| }; |
| auto B = [&](const Expression* value) -> const Expression* { |
| if (width == 1) { |
| return b.Call<bool>(value); |
| } |
| return b.Call(b.ty.vec<bool>(width), value); |
| }; |
| b.Func( |
| name, |
| tint::Vector{ |
| b.Param("v", T(ty)), |
| }, |
| T(ty), |
| tint::Vector{ |
| // var x = U(v); |
| b.Decl(b.Var("x", b.Call(U(), b.Expr("v")))), |
| // let b16 = select(16, 0, bool(x & 0x0000ffff)); |
| b.Decl(b.Let("b16", b.Call("select", V(16), V(0), B(b.And("x", V(0x0000ffff)))))), |
| // x = x >> b16; |
| b.Assign("x", b.Shr("x", "b16")), |
| // let b8 = select(8, 0, bool(x & 0x000000ff)); |
| b.Decl(b.Let("b8", b.Call("select", V(8), V(0), B(b.And("x", V(0x000000ff)))))), |
| // x = x >> b8; |
| b.Assign("x", b.Shr("x", "b8")), |
| // let b4 = select(4, 0, bool(x & 0x0000000f)); |
| b.Decl(b.Let("b4", b.Call("select", V(4), V(0), B(b.And("x", V(0x0000000f)))))), |
| // x = x >> b4; |
| b.Assign("x", b.Shr("x", "b4")), |
| // let b2 = select(2, 0, bool(x & 0x00000003)); |
| b.Decl(b.Let("b2", b.Call("select", V(2), V(0), B(b.And("x", V(0x00000003)))))), |
| // x = x >> b2; |
| b.Assign("x", b.Shr("x", "b2")), |
| // let b1 = select(1, 0, bool(x & 0x00000001)); |
| b.Decl(b.Let("b1", b.Call("select", V(1), V(0), B(b.And("x", V(0x00000001)))))), |
| // let is_zero = select(0, 0xffffffff, x == 0); |
| b.Decl(b.Let("is_zero", b.Call("select", V(0), V(0xffffffff), b.Equal("x", V(0))))), |
| // return R(b16 | b8 | b4 | b2 | b1 | is_zero); |
| b.Return(b.Call( |
| T(ty), b.Or(b.Or(b.Or(b.Or(b.Or("b16", "b8"), "b4"), "b2"), "b1"), "is_zero"))), |
| }); |
| return name; |
| } |
| |
| /// Builds the polyfill function for the `fwidthFine` builtin |
| /// @param ty the parameter and return type for the function |
| /// @return the polyfill function name |
| Symbol fwidthFine(const core::type::Type* ty) { |
| auto name = b.Symbols().New("tint_fwidth_fine"); |
| // WGSL polyfill function: |
| // fn tint_fwidth_fine(v : T) -> T { |
| // return abs(dpdxFine(v)) + abs(dpdyFine(v)); |
| // } |
| auto body = tint::Vector{ |
| b.Return(b.Add(b.Call("abs", b.Call("dpdxFine", "v")), |
| b.Call("abs", b.Call("dpdyFine", "v")))), |
| }; |
| b.Func(name, |
| tint::Vector{ |
| b.Param("v", T(ty)), |
| }, |
| T(ty), body); |
| return name; |
| } |
| |
| /// Builds the polyfill function for the `insertBits` builtin |
| /// @param ty the parameter and return type for the function |
| /// @return the polyfill function name |
| Symbol insertBits(const core::type::Type* ty) { |
| auto name = b.Symbols().New("tint_insert_bits"); |
| uint32_t width = WidthOf(ty); |
| |
| // Currently in WGSL parameters of insertBits must be i32, u32, vecN<i32> or vecN<u32> |
| if (TINT_UNLIKELY(((!ty->DeepestElement()->IsAnyOf<core::type::I32, core::type::U32>())))) { |
| TINT_ICE() |
| << "insertBits polyfill only support i32, u32, and vector of i32 or u32, got " |
| << ty->FriendlyName(); |
| return {}; |
| } |
| |
| constexpr uint32_t W = 32u; // 32-bit |
| |
| auto V = [&](auto value) -> const Expression* { |
| const Expression* expr = b.Expr(value); |
| if (!ty->is_unsigned_integer_scalar_or_vector()) { |
| expr = b.Call<i32>(expr); |
| } |
| if (ty->Is<core::type::Vector>()) { |
| expr = b.Call(T(ty), expr); |
| } |
| return expr; |
| }; |
| auto U = [&](auto value) -> const Expression* { |
| if (width == 1) { |
| return b.Expr(value); |
| } |
| return b.vec(b.ty.u32(), width, value); |
| }; |
| |
| // Polyfill algorithm: |
| // s = min(offset, 32u); |
| // e = min(32u, (s + count)); |
| // mask = (((1u << s) - 1u) ^ ((1u << e) - 1u)); |
| // return (((n << s) & mask) | (v & ~(mask))); |
| // Note that the algorithm above use the left-shifting in C++ manner, but in WGSL, HLSL, MSL |
| // the rhs are modulo to bit-width of lhs (that is 32u in this case), and in GLSL the result |
| // is undefined if rhs is greater than or equal to bit-width of lhs. The results of `x << y` |
| // in C++ and HLSL are different when `y >= 32u`, and the `s` and `e` defined above can be |
| // 32u, which are cases we must handle specially. Replace all `(x << y)` to |
| // `select(Tx(), x << y, y < 32u)`, in which `Tx` is the type of x, where y can be greater |
| // than or equal to 32u. |
| // WGSL polyfill function: |
| // fn tint_insert_bits(v : T, n : T, offset : u32, count : u32) -> T { |
| // let e = offset + count; |
| // let mask = ( |
| // (select(0u, 1u << offset, offset < 32u) - 1u) ^ |
| // (select(0u, 1u << e, e < 32u) - 1u) |
| // ); |
| // return ((select(T(), n << offset, offset < 32u) & mask) | (v & ~(mask))); |
| // } |
| |
| tint::Vector<const Statement*, 8> body; |
| |
| switch (cfg.builtins.insert_bits) { |
| case Level::kFull: |
| // let e = offset + count; |
| body.Push(b.Decl(b.Let("e", b.Add("offset", "count")))); |
| |
| // let mask = ( |
| // (select(0u, 1u << offset, offset < 32u) - 1u) ^ |
| // (select(0u, 1u << e, e < 32u) - 1u) |
| // ); |
| body.Push(b.Decl(b.Let( |
| "mask", |
| b.Xor( // |
| b.Sub( |
| b.Call("select", 0_u, b.Shl(1_u, "offset"), b.LessThan("offset", 32_u)), |
| 1_u), |
| b.Sub(b.Call("select", 0_u, b.Shl(1_u, "e"), b.LessThan("e", 32_u)), |
| 1_u) // |
| )))); |
| |
| // return ((select(T(), n << offset, offset < 32u) & mask) | (v & ~(mask))); |
| body.Push( |
| b.Return(b.Or(b.And(b.Call("select", b.Call(T(ty)), b.Shl("n", U("offset")), |
| b.LessThan("offset", 32_u)), |
| V("mask")), |
| b.And("v", V(b.Complement("mask")))))); |
| |
| break; |
| case Level::kClampParameters: |
| body.Push(b.Decl(b.Let("s", b.Call("min", "offset", u32(W))))); |
| body.Push(b.Decl(b.Let("e", b.Call("min", u32(W), b.Add("s", "count"))))); |
| body.Push(b.Return(b.Call("insertBits", "v", "n", "s", b.Sub("e", "s")))); |
| break; |
| default: |
| TINT_ICE() << "unhandled polyfill level: " |
| << static_cast<int>(cfg.builtins.insert_bits); |
| return {}; |
| } |
| |
| b.Func(name, |
| tint::Vector{ |
| b.Param("v", T(ty)), |
| b.Param("n", T(ty)), |
| b.Param("offset", b.ty.u32()), |
| b.Param("count", b.ty.u32()), |
| }, |
| T(ty), body); |
| |
| return name; |
| } |
| |
| /// Builds the polyfill function for the `reflect` builtin |
| /// @param ty the parameter and return type for the function |
| /// @return the polyfill function name |
| Symbol reflect(const core::type::Type* ty) { |
| auto name = b.Symbols().New("tint_reflect"); |
| |
| // WGSL polyfill function: |
| // fn tint_reflect(e1 : T, e2 : T) -> T { |
| // let factor = (-2.0 * dot(e1, e2)); |
| // return (e1 + (factor * e2)); |
| // } |
| // Using -2.0 instead of 2.0 in factor to prevent the optimization that cause wrong result. |
| // See https://crbug.com/tint/1798 for more details. |
| auto body = tint::Vector{ |
| b.Decl(b.Let("factor", b.Mul(-2.0_a, b.Call("dot", "e1", "e2")))), |
| b.Return(b.Add("e1", b.Mul("factor", "e2"))), |
| }; |
| b.Func(name, |
| tint::Vector{ |
| b.Param("e1", T(ty)), |
| b.Param("e2", T(ty)), |
| }, |
| T(ty), body); |
| |
| return name; |
| } |
| |
| /// Builds the polyfill function for the `saturate` builtin |
| /// @param ty the parameter and return type for the function |
| /// @return the polyfill function name |
| Symbol saturate(const core::type::Type* ty) { |
| auto name = b.Symbols().New("tint_saturate"); |
| auto body = tint::Vector{ |
| b.Return(b.Call("clamp", "v", b.Call(T(ty), 0_a), b.Call(T(ty), 1_a))), |
| }; |
| b.Func(name, |
| tint::Vector{ |
| b.Param("v", T(ty)), |
| }, |
| T(ty), body); |
| |
| return name; |
| } |
| |
| /// Builds the polyfill function for the `sign` builtin when the element type is integer |
| /// @param ty the parameter and return type for the function |
| /// @return the polyfill function name |
| Symbol sign_int(const core::type::Type* ty) { |
| const uint32_t width = WidthOf(ty); |
| auto zero = [&] { return ScalarOrVector(width, 0_a); }; |
| |
| // pos_or_neg_one = (v > 0) ? 1 : -1 |
| auto pos_or_neg_one = b.Call("select", // |
| ScalarOrVector(width, -1_a), // |
| ScalarOrVector(width, 1_a), // |
| b.GreaterThan("v", zero())); |
| |
| auto name = b.Symbols().New("tint_sign"); |
| b.Func(name, |
| tint::Vector{ |
| b.Param("v", T(ty)), |
| }, |
| T(ty), |
| tint::Vector{ |
| b.Return(b.Call("select", pos_or_neg_one, zero(), b.Equal("v", zero()))), |
| }); |
| |
| return name; |
| } |
| |
| /// Builds the polyfill function for the `textureSampleBaseClampToEdge` builtin, when the |
| /// texture type is texture_2d<f32>. |
| /// @return the polyfill function name |
| Symbol textureSampleBaseClampToEdge_2d_f32() { |
| auto name = b.Symbols().New("tint_textureSampleBaseClampToEdge"); |
| auto body = tint::Vector{ |
| b.Decl(b.Let("dims", b.Call(b.ty.vec2<f32>(), b.Call("textureDimensions", "t", 0_a)))), |
| b.Decl(b.Let("half_texel", b.Div(b.Call<vec2<f32>>(0.5_a), "dims"))), |
| b.Decl( |
| b.Let("clamped", b.Call("clamp", "coord", "half_texel", b.Sub(1_a, "half_texel")))), |
| b.Return(b.Call("textureSampleLevel", "t", "s", "clamped", 0_a)), |
| }; |
| b.Func( |
| name, |
| tint::Vector{ |
| b.Param("t", b.ty.sampled_texture(core::type::TextureDimension::k2d, b.ty.f32())), |
| b.Param("s", b.ty.sampler(core::type::SamplerKind::kSampler)), |
| b.Param("coord", b.ty.vec2<f32>()), |
| }, |
| b.ty.vec4<f32>(), body); |
| return name; |
| } |
| |
| /// Builds the polyfill function for the `quantizeToF16` builtin, by replacing the vector form |
| /// with scalar calls. |
| /// @param vec the vector type |
| /// @return the polyfill function name |
| Symbol quantizeToF16(const core::type::Vector* vec) { |
| auto name = b.Symbols().New("tint_quantizeToF16"); |
| tint::Vector<const Expression*, 4> args; |
| for (uint32_t i = 0; i < vec->Width(); i++) { |
| args.Push(b.Call("quantizeToF16", b.IndexAccessor("v", u32(i)))); |
| } |
| b.Func(name, |
| tint::Vector{ |
| b.Param("v", T(vec)), |
| }, |
| T(vec), |
| tint::Vector{ |
| b.Return(b.Call(T(vec), std::move(args))), |
| }); |
| return name; |
| } |
| |
| /// Builds the polyfill function for the `workgroupUniformLoad` builtin. |
| /// @param type the type being loaded |
| /// @return the polyfill function name |
| Symbol workgroupUniformLoad(const core::type::Type* type) { |
| auto name = b.Symbols().New("tint_workgroupUniformLoad"); |
| b.Func(name, |
| tint::Vector{ |
| b.Param("p", b.ty.ptr<workgroup>(T(type))), |
| }, |
| T(type), |
| tint::Vector{ |
| b.CallStmt(b.Call("workgroupBarrier")), |
| b.Decl(b.Let("result", b.Deref("p"))), |
| b.CallStmt(b.Call("workgroupBarrier")), |
| b.Return("result"), |
| }); |
| return name; |
| } |
| |
| /// Builds the polyfill function to value convert a scalar or vector of f32 to an i32 or u32 (or |
| /// vector of). |
| /// @param source the type of the value being converted |
| /// @param target the target conversion type |
| /// @return the polyfill function name |
| Symbol ConvF32ToIU32(const core::type::Type* source, const core::type::Type* target) { |
| struct Limits { |
| AFloat low_condition; |
| AInt low_limit; |
| AFloat high_condition; |
| AInt high_limit; |
| }; |
| const bool is_signed = target->is_signed_integer_scalar_or_vector(); |
| const Limits limits = is_signed ? Limits{ |
| /* low_condition */ -AFloat(0x80000000), |
| /* low_limit */ -AInt(0x80000000), |
| /* high_condition */ AFloat(0x7fffff80), |
| /* high_limit */ AInt(0x7fffffff), |
| } |
| : Limits{ |
| /* low_condition */ AFloat(0), |
| /* low_limit */ AInt(0), |
| /* high_condition */ AFloat(0xffffff00), |
| /* high_limit */ AInt(0xffffffff), |
| }; |
| |
| const uint32_t width = WidthOf(target); |
| |
| // select(target(v), low_limit, v < low_condition) |
| auto* select_low = b.Call(wgsl::BuiltinFn::kSelect, // |
| b.Call(T(target), "v"), // |
| ScalarOrVector(width, limits.low_limit), // |
| b.LessThan("v", ScalarOrVector(width, limits.low_condition))); |
| |
| // select(high_limit, select_low, v < high_condition) |
| auto* select_high = b.Call(wgsl::BuiltinFn::kSelect, // |
| ScalarOrVector(width, limits.high_limit), // |
| select_low, // |
| b.LessThan("v", ScalarOrVector(width, limits.high_condition))); |
| |
| auto name = b.Symbols().New(is_signed ? "tint_ftoi" : "tint_ftou"); |
| b.Func(name, tint::Vector{b.Param("v", T(source))}, T(target), |
| tint::Vector{b.Return(select_high)}); |
| return name; |
| } |
| |
| /// Builds the polyfill function for the `dot4I8Packed` builtin |
| /// @return the polyfill function name |
| Symbol Dot4I8Packed() { |
| using vec4i = vec4<i32>; |
| using vec4u = vec4<u32>; |
| |
| auto name = b.Symbols().New("tint_dot4_i8_packed"); |
| |
| auto body = tint::Vector{ |
| // const n = vec4u(24, 16, 8, 0); |
| // let a_i8 = bitcast<vec4i>(vec4u(a) << n) >> vec4u(24); |
| // let b_i8 = bitcast<vec4i>(vec4u(b) << n) >> vec4u(24); |
| // return dot(a_i8, b_i8); |
| b.Decl(b.Const("n", b.Call<vec4u>(24_a, 16_a, 8_a, 0_a))), |
| b.Decl(b.Let("a_i8", b.Shr(b.Bitcast<vec4i>(b.Shl(b.Call<vec4u>("a"), "n")), |
| b.Call<vec4u>(24_a)))), |
| b.Decl(b.Let("b_i8", b.Shr(b.Bitcast<vec4i>(b.Shl(b.Call<vec4u>("b"), "n")), |
| b.Call<vec4u>(24_a)))), |
| b.Return(b.Call("dot", "a_i8", "b_i8")), |
| }; |
| b.Func(name, |
| tint::Vector{ |
| b.Param("a", b.ty.u32()), |
| b.Param("b", b.ty.u32()), |
| }, |
| b.ty.i32(), body); |
| |
| return name; |
| } |
| |
| /// Builds the polyfill function for the `dot4U8Packed` builtin |
| /// @return the polyfill function name |
| Symbol Dot4U8Packed() { |
| using vec4u = vec4<u32>; |
| auto name = b.Symbols().New("tint_dot4_u8_packed"); |
| |
| auto body = tint::Vector{ |
| // const n = vec4u(24, 16, 8, 0); |
| // let a_u8 = (vec4u(a) >> n) & vec4u(0xff); |
| // let b_u8 = (vec4u(b) >> n) & vec4u(0xff); |
| // return dot(a_u8, b_u8); |
| b.Decl(b.Const("n", b.Call<vec4u>(24_a, 16_a, 8_a, 0_a))), |
| b.Decl(b.Let("a_u8", b.And(b.Shr(b.Call<vec4u>("a"), "n"), b.Call<vec4u>(0xff_a)))), |
| b.Decl(b.Let("b_u8", b.And(b.Shr(b.Call<vec4u>("b"), "n"), b.Call<vec4u>(0xff_a)))), |
| b.Return(b.Call("dot", "a_u8", "b_u8")), |
| }; |
| b.Func(name, |
| tint::Vector{ |
| b.Param("a", b.ty.u32()), |
| b.Param("b", b.ty.u32()), |
| }, |
| b.ty.u32(), body); |
| |
| return name; |
| } |
| |
| /// Builds the polyfill function for the `pack4xI8` builtin |
| /// @return the polyfill function name |
| Symbol Pack4xI8() { |
| using vec4u = vec4<u32>; |
| |
| auto name = b.Symbols().New("tint_pack_4xi8"); |
| |
| auto body = tint::Vector{ |
| // const n = vec4u(0, 8, 16, 24); |
| // let a_u32 = bitcast<vec4u>(a); |
| // let a_u8 = (a_u32 & vec4u(0xff)) << n; |
| // return dot(a_u8, vec4u(1)); |
| b.Decl(b.Const("n", b.Call<vec4u>(0_a, 8_a, 16_a, 24_a))), |
| b.Decl(b.Let("a_u32", b.Bitcast<vec4u>("a"))), |
| b.Decl(b.Let("a_u8", b.Shl(b.And("a_u32", b.Call<vec4u>(0xff_a)), "n"))), |
| b.Return(b.Call("dot", "a_u8", b.Call<vec4u>(1_a))), |
| }; |
| b.Func(name, |
| tint::Vector{ |
| b.Param("a", b.ty.vec4<i32>()), |
| }, |
| b.ty.u32(), body); |
| |
| return name; |
| } |
| |
| /// Builds the polyfill function for the `pack4xU8` builtin |
| /// @return the polyfill function name |
| Symbol Pack4xU8() { |
| using vec4u = vec4<u32>; |
| |
| auto name = b.Symbols().New("tint_pack_4xu8"); |
| |
| auto body = tint::Vector{ |
| // const n = vec4u(0, 8, 16, 24); |
| // let a_u8 = (a & vec4u(0xff)) << n; |
| // return dot(a_u8, vec4u(1)); |
| b.Decl(b.Const("n", b.Call<vec4u>(0_a, 8_a, 16_a, 24_a))), |
| b.Decl(b.Let("a_u8", b.Shl(b.And("a", b.Call<vec4u>(0xff_a)), "n"))), |
| b.Return(b.Call("dot", "a_u8", b.Call<vec4u>(1_a))), |
| }; |
| b.Func(name, |
| tint::Vector{ |
| b.Param("a", b.ty.vec4<u32>()), |
| }, |
| b.ty.u32(), body); |
| |
| return name; |
| } |
| |
| /// Builds the polyfill function for the `pack4xI8Clamp` builtin |
| /// @return the polyfill function name |
| Symbol Pack4xI8Clamp() { |
| using vec4i = vec4<i32>; |
| using vec4u = vec4<u32>; |
| |
| auto name = b.Symbols().New("tint_pack_4xi8_clamp"); |
| |
| auto body = tint::Vector{ |
| // const n = vec4u(0, 8, 16, 24); |
| // let a_clamp = clamp(a, vec4i(-128), vec4i(127)); |
| // let a_u32 = bitcast<vec4u>(a_clamp); |
| // let a_u8 = (a_u32 & vec4u(0xff)) << n; |
| // return dot(a_u8, vec4u(1)); |
| b.Decl(b.Const("n", b.Call<vec4u>(0_a, 8_a, 16_a, 24_a))), |
| b.Decl(b.Let("a_clamp", |
| b.Call("clamp", "a", b.Call<vec4i>(-128_a), b.Call<vec4i>(127_a)))), |
| b.Decl(b.Let("a_u32", b.Bitcast<vec4u>("a_clamp"))), |
| b.Decl(b.Let("a_u8", b.Shl(b.And("a_u32", b.Call<vec4u>(0xff_a)), "n"))), |
| b.Return(b.Call("dot", "a_u8", b.Call<vec4u>(1_a))), |
| }; |
| b.Func(name, |
| tint::Vector{ |
| b.Param("a", b.ty.vec4<i32>()), |
| }, |
| b.ty.u32(), body); |
| |
| return name; |
| } |
| |
| /// Builds the polyfill function for the `pack4xU8Clamp` builtin |
| /// @return the polyfill function name |
| Symbol Pack4xU8Clamp() { |
| using vec4u = vec4<u32>; |
| |
| auto name = b.Symbols().New("tint_pack_4xu8_clamp"); |
| |
| auto body = tint::Vector{ |
| // const n = vec4u(0, 8, 16, 24); |
| // let a_clamp = clamp(a, vec4u(0), vec4u(255)); |
| // let a_u8 = a_clamp << n; |
| // return dot(a_u8, vec4u(1)); |
| b.Decl(b.Const("n", b.Call<vec4u>(0_a, 8_a, 16_a, 24_a))), |
| b.Decl( |
| b.Let("a_clamp", b.Call("clamp", "a", b.Call<vec4u>(0_a), b.Call<vec4u>(255_a)))), |
| b.Decl(b.Let("a_u8", b.Call<vec4u>(b.Shl("a_clamp", "n")))), |
| b.Return(b.Call("dot", "a_u8", b.Call<vec4u>(1_a))), |
| }; |
| b.Func(name, |
| tint::Vector{ |
| b.Param("a", b.ty.vec4<u32>()), |
| }, |
| b.ty.u32(), body); |
| |
| return name; |
| } |
| |
| /// Builds the polyfill function for the `unpack4xI8` builtin |
| /// @return the polyfill function name |
| Symbol Unpack4xI8() { |
| using vec4i = vec4<i32>; |
| using vec4u = vec4<u32>; |
| |
| auto name = b.Symbols().New("tint_unpack_4xi8"); |
| |
| auto body = tint::Vector{ |
| // const n = vec4u(24, 16, 8, 0); |
| // let a_vec4u = vec4u(a); |
| // let a_vec4i = bitcast<vec4i>(a_vec4u << n); |
| // return a_vec4i >> vec4u(24); |
| b.Decl(b.Const("n", b.Call<vec4u>(24_a, 16_a, 8_a, 0_a))), |
| b.Decl(b.Let("a_vec4u", b.Call<vec4u>("a"))), |
| b.Decl(b.Let("a_vec4i", b.Bitcast<vec4i>(b.Shl("a_vec4u", "n")))), |
| b.Return(b.Shr("a_vec4i", b.Call<vec4u>(24_a))), |
| }; |
| b.Func(name, |
| tint::Vector{ |
| b.Param("a", b.ty.u32()), |
| }, |
| b.ty.vec4<i32>(), body); |
| |
| return name; |
| } |
| |
| /// Builds the polyfill function for the `unpack4xU8` builtin |
| /// @return the polyfill function name |
| Symbol Unpack4xU8() { |
| using vec4u = vec4<u32>; |
| |
| auto name = b.Symbols().New("tint_unpack_4xu8"); |
| |
| auto body = tint::Vector{ |
| // const n = vec4u(0, 8, 16, 24); |
| // const a_vec4u = vec4u(a) >> n; |
| // return a_vec4u & vec4u(0xff); |
| b.Decl(b.Const("n", b.Call<vec4u>(0_a, 8_a, 16_a, 24_a))), |
| b.Decl(b.Let("a_vec4u", b.Shr(b.Call<vec4u>("a"), "n"))), |
| b.Return(b.And("a_vec4u", b.Call<vec4u>(0xff_a))), |
| }; |
| b.Func(name, |
| tint::Vector{ |
| b.Param("a", b.ty.u32()), |
| }, |
| b.ty.vec4<u32>(), body); |
| |
| return name; |
| } |
| |
| //////////////////////////////////////////////////////////////////////////// |
| // Inline polyfills |
| //////////////////////////////////////////////////////////////////////////// |
| |
| /// Builds the polyfill inline expression for a bitshift left or bitshift right, ensuring that |
| /// the RHS is modulo the bit-width of the LHS. |
| /// @param bin_op the original BinaryExpression |
| /// @return the polyfill value for bitshift operation |
| const Expression* BitshiftModulo(const BinaryExpression* bin_op) { |
| auto* lhs_ty = src.TypeOf(bin_op->lhs)->UnwrapRef(); |
| auto* rhs_ty = src.TypeOf(bin_op->rhs)->UnwrapRef(); |
| auto* lhs_el_ty = lhs_ty->DeepestElement(); |
| const Expression* mask = b.Expr(AInt(lhs_el_ty->Size() * 8 - 1)); |
| if (rhs_ty->Is<core::type::Vector>()) { |
| mask = b.Call(CreateASTTypeFor(ctx, rhs_ty), mask); |
| } |
| auto* lhs = ctx.Clone(bin_op->lhs); |
| auto* rhs = b.And(ctx.Clone(bin_op->rhs), mask); |
| return b.create<BinaryExpression>(ctx.Clone(bin_op->source), bin_op->op, lhs, rhs); |
| } |
| |
| /// Builds the polyfill inline expression for a integer divide or modulo, preventing DBZs and |
| /// integer overflows. |
| /// @param bin_op the original BinaryExpression |
| /// @return the polyfill divide or modulo |
| const Expression* IntDivMod(const BinaryExpression* bin_op) { |
| auto* lhs_ty = src.TypeOf(bin_op->lhs)->UnwrapRef(); |
| auto* rhs_ty = src.TypeOf(bin_op->rhs)->UnwrapRef(); |
| BinaryOpSignature sig{bin_op->op, lhs_ty, rhs_ty}; |
| auto fn = binary_op_polyfills.GetOrAdd(sig, [&] { |
| const bool is_div = bin_op->op == core::BinaryOp::kDivide; |
| |
| const auto [lhs_el_ty, lhs_width] = lhs_ty->Elements(lhs_ty, 1); |
| const auto [rhs_el_ty, rhs_width] = rhs_ty->Elements(rhs_ty, 1); |
| |
| const uint32_t width = std::max(lhs_width, rhs_width); |
| |
| const char* lhs = "lhs"; |
| const char* rhs = "rhs"; |
| |
| tint::Vector<const Statement*, 4> body; |
| |
| if (lhs_width < width) { |
| // lhs is scalar, rhs is vector. Convert lhs to vector. |
| body.Push(b.Decl(b.Let("l", b.vec(T(lhs_el_ty), width, b.Expr(lhs))))); |
| lhs = "l"; |
| } |
| if (rhs_width < width) { |
| // lhs is vector, rhs is scalar. Convert rhs to vector. |
| body.Push(b.Decl(b.Let("r", b.vec(T(rhs_el_ty), width, b.Expr(rhs))))); |
| rhs = "r"; |
| } |
| |
| auto name = b.Symbols().New(is_div ? "tint_div" : "tint_mod"); |
| |
| auto* rhs_is_zero = b.Equal(rhs, ScalarOrVector(width, 0_a)); |
| |
| if (lhs_ty->is_signed_integer_scalar_or_vector()) { |
| const auto bits = lhs_el_ty->Size() * 8; |
| auto min_int = AInt(AInt::kLowestValue >> (AInt::kNumBits - bits)); |
| const Expression* lhs_is_min = b.Equal(lhs, ScalarOrVector(width, min_int)); |
| const Expression* rhs_is_minus_one = b.Equal(rhs, ScalarOrVector(width, -1_a)); |
| // use_one = rhs_is_zero | ((lhs == MIN_INT) & (rhs == -1)) |
| auto* use_one = b.Or(rhs_is_zero, b.And(lhs_is_min, rhs_is_minus_one)); |
| |
| // Special handling for mod in case either operand is negative, as negative operands |
| // for % is undefined behaviour for most backends (HLSL, MSL, GLSL, SPIR-V). |
| if (!is_div) { |
| const char* rhs_or_one = "rhs_or_one"; |
| body.Push(b.Decl(b.Let( |
| rhs_or_one, b.Call("select", rhs, ScalarOrVector(width, 1_a), use_one)))); |
| |
| // Is either operand negative? |
| // (lhs | rhs) & (1<<31) |
| auto sign_bit_mask = ScalarOrVector(width, u32(1 << (bits - 1))); |
| auto* lhs_or_rhs = CastScalarOrVector<u32>(width, b.Or(lhs, rhs_or_one)); |
| auto* lhs_or_rhs_is_neg = |
| b.NotEqual(b.And(lhs_or_rhs, sign_bit_mask), ScalarOrVector(width, 0_u)); |
| |
| // lhs - trunc(lhs / rhs) * rhs (note: integral division truncates) |
| auto* slow_mod = b.Sub(lhs, b.Mul(b.Div(lhs, rhs_or_one), rhs_or_one)); |
| |
| // lhs % rhs |
| auto* fast_mod = b.Mod(lhs, rhs_or_one); |
| |
| auto* use_slow = b.Call("any", lhs_or_rhs_is_neg); |
| |
| body.Push(b.If(use_slow, b.Block(b.Return(slow_mod)), |
| b.Else(b.Block(b.Return(fast_mod))))); |
| |
| } else { |
| auto* rhs_or_one = b.Call("select", rhs, ScalarOrVector(width, 1_a), use_one); |
| body.Push(b.Return(is_div ? b.Div(lhs, rhs_or_one) : b.Mod(lhs, rhs_or_one))); |
| } |
| |
| } else { |
| auto* rhs_or_one = b.Call("select", rhs, ScalarOrVector(width, 1_a), rhs_is_zero); |
| body.Push(b.Return(is_div ? b.Div(lhs, rhs_or_one) : b.Mod(lhs, rhs_or_one))); |
| } |
| |
| b.Func(name, |
| tint::Vector{ |
| b.Param("lhs", T(lhs_ty)), |
| b.Param("rhs", T(rhs_ty)), |
| }, |
| width == 1 ? T(lhs_ty) : b.ty.vec(T(lhs_el_ty), width), // return type |
| std::move(body)); |
| |
| return name; |
| }); |
| auto* lhs = ctx.Clone(bin_op->lhs); |
| auto* rhs = ctx.Clone(bin_op->rhs); |
| return b.Call(fn, lhs, rhs); |
| } |
| |
| /// Builds the polyfill inline expression for a precise float modulo, as defined in the spec. |
| /// @param bin_op the original BinaryExpression |
| /// @return the polyfill divide or modulo |
| const Expression* PreciseFloatMod(const BinaryExpression* bin_op) { |
| auto* lhs_ty = src.TypeOf(bin_op->lhs)->UnwrapRef(); |
| auto* rhs_ty = src.TypeOf(bin_op->rhs)->UnwrapRef(); |
| BinaryOpSignature sig{bin_op->op, lhs_ty, rhs_ty}; |
| auto fn = binary_op_polyfills.GetOrAdd(sig, [&] { |
| const auto [lhs_el_ty, lhs_width] = lhs_ty->Elements(lhs_ty, 1); |
| const auto [rhs_el_ty, rhs_width] = rhs_ty->Elements(rhs_ty, 1); |
| |
| const uint32_t width = std::max(lhs_width, rhs_width); |
| |
| const char* lhs = "lhs"; |
| const char* rhs = "rhs"; |
| |
| tint::Vector<const Statement*, 4> body; |
| |
| if (lhs_width < width) { |
| // lhs is scalar, rhs is vector. Convert lhs to vector. |
| body.Push(b.Decl(b.Let("l", b.vec(T(lhs_el_ty), width, b.Expr(lhs))))); |
| lhs = "l"; |
| } |
| if (rhs_width < width) { |
| // lhs is vector, rhs is scalar. Convert rhs to vector. |
| body.Push(b.Decl(b.Let("r", b.vec(T(rhs_el_ty), width, b.Expr(rhs))))); |
| rhs = "r"; |
| } |
| |
| auto name = b.Symbols().New("tint_float_mod"); |
| |
| // lhs - trunc(lhs / rhs) * rhs |
| auto* precise_mod = b.Sub(lhs, b.Mul(b.Call("trunc", b.Div(lhs, rhs)), rhs)); |
| body.Push(b.Return(precise_mod)); |
| |
| b.Func(name, |
| tint::Vector{ |
| b.Param("lhs", T(lhs_ty)), |
| b.Param("rhs", T(rhs_ty)), |
| }, |
| width == 1 ? T(lhs_ty) : b.ty.vec(T(lhs_el_ty), width), // return type |
| std::move(body)); |
| |
| return name; |
| }); |
| auto* lhs = ctx.Clone(bin_op->lhs); |
| auto* rhs = ctx.Clone(bin_op->rhs); |
| return b.Call(fn, lhs, rhs); |
| } |
| |
| /// @returns the AST type for the given sem type |
| Type T(const core::type::Type* ty) { return CreateASTTypeFor(ctx, ty); } |
| |
| /// @returns 1 if `ty` is not a vector, otherwise the vector width |
| uint32_t WidthOf(const core::type::Type* ty) const { |
| if (auto* v = ty->As<core::type::Vector>()) { |
| return v->Width(); |
| } |
| return 1; |
| } |
| |
| /// @returns a scalar or vector with the given width, with each element with |
| /// the given value. |
| template <typename T> |
| const Expression* ScalarOrVector(uint32_t width, T value) { |
| if (width == 1) { |
| return b.Expr(value); |
| } |
| return b.Call(b.ty.vec<T>(width), value); |
| } |
| |
| template <typename To> |
| const Expression* CastScalarOrVector(uint32_t width, const Expression* e) { |
| if (width == 1) { |
| return b.Call(b.ty.Of<To>(), e); |
| } |
| return b.Call(b.ty.vec<To>(width), e); |
| } |
| |
| /// Examines the call expression @p expr, applying any necessary polyfill transforms |
| void Call(const CallExpression* expr) { |
| auto* call = src.Sem().Get(expr)->UnwrapMaterialize()->As<sem::Call>(); |
| if (!call || call->Stage() == core::EvaluationStage::kConstant || |
| call->Stage() == core::EvaluationStage::kNotEvaluated) { |
| return; // Don't polyfill @const expressions |
| } |
| Symbol fn = Switch( |
| call->Target(), // |
| [&](const sem::BuiltinFn* builtin) { |
| switch (builtin->Fn()) { |
| case wgsl::BuiltinFn::kAcosh: |
| if (cfg.builtins.acosh != Level::kNone) { |
| return builtin_polyfills.GetOrAdd( |
| builtin, [&] { return acosh(builtin->ReturnType()); }); |
| } |
| return Symbol{}; |
| |
| case wgsl::BuiltinFn::kAsinh: |
| if (cfg.builtins.asinh) { |
| return builtin_polyfills.GetOrAdd( |
| builtin, [&] { return asinh(builtin->ReturnType()); }); |
| } |
| return Symbol{}; |
| |
| case wgsl::BuiltinFn::kAtanh: |
| if (cfg.builtins.atanh != Level::kNone) { |
| return builtin_polyfills.GetOrAdd( |
| builtin, [&] { return atanh(builtin->ReturnType()); }); |
| } |
| return Symbol{}; |
| |
| case wgsl::BuiltinFn::kClamp: |
| if (cfg.builtins.clamp_int) { |
| auto& sig = builtin->Signature(); |
| if (sig.parameters[0]->Type()->is_integer_scalar_or_vector()) { |
| return builtin_polyfills.GetOrAdd( |
| builtin, [&] { return clampInteger(builtin->ReturnType()); }); |
| } |
| } |
| return Symbol{}; |
| |
| case wgsl::BuiltinFn::kCountLeadingZeros: |
| if (cfg.builtins.count_leading_zeros) { |
| return builtin_polyfills.GetOrAdd( |
| builtin, [&] { return countLeadingZeros(builtin->ReturnType()); }); |
| } |
| return Symbol{}; |
| |
| case wgsl::BuiltinFn::kCountTrailingZeros: |
| if (cfg.builtins.count_trailing_zeros) { |
| return builtin_polyfills.GetOrAdd( |
| builtin, [&] { return countTrailingZeros(builtin->ReturnType()); }); |
| } |
| return Symbol{}; |
| |
| case wgsl::BuiltinFn::kExtractBits: |
| if (cfg.builtins.extract_bits != Level::kNone) { |
| return builtin_polyfills.GetOrAdd( |
| builtin, [&] { return extractBits(builtin->ReturnType()); }); |
| } |
| return Symbol{}; |
| |
| case wgsl::BuiltinFn::kFirstLeadingBit: |
| if (cfg.builtins.first_leading_bit) { |
| return builtin_polyfills.GetOrAdd( |
| builtin, [&] { return firstLeadingBit(builtin->ReturnType()); }); |
| } |
| return Symbol{}; |
| |
| case wgsl::BuiltinFn::kFirstTrailingBit: |
| if (cfg.builtins.first_trailing_bit) { |
| return builtin_polyfills.GetOrAdd( |
| builtin, [&] { return firstTrailingBit(builtin->ReturnType()); }); |
| } |
| return Symbol{}; |
| |
| case wgsl::BuiltinFn::kFwidthFine: |
| if (cfg.builtins.fwidth_fine) { |
| return builtin_polyfills.GetOrAdd( |
| builtin, [&] { return fwidthFine(builtin->ReturnType()); }); |
| } |
| return Symbol{}; |
| |
| case wgsl::BuiltinFn::kInsertBits: |
| if (cfg.builtins.insert_bits != Level::kNone) { |
| return builtin_polyfills.GetOrAdd( |
| builtin, [&] { return insertBits(builtin->ReturnType()); }); |
| } |
| return Symbol{}; |
| |
| case wgsl::BuiltinFn::kReflect: |
| // Only polyfill for vec2<f32>. See https://crbug.com/tint/1798 for |
| // more details. |
| if (cfg.builtins.reflect_vec2_f32) { |
| auto& sig = builtin->Signature(); |
| auto* vec = sig.return_type->As<core::type::Vector>(); |
| if (vec && vec->Width() == 2 && vec->type()->Is<core::type::F32>()) { |
| return builtin_polyfills.GetOrAdd( |
| builtin, [&] { return reflect(builtin->ReturnType()); }); |
| } |
| } |
| return Symbol{}; |
| |
| case wgsl::BuiltinFn::kSaturate: |
| if (cfg.builtins.saturate) { |
| return builtin_polyfills.GetOrAdd( |
| builtin, [&] { return saturate(builtin->ReturnType()); }); |
| } |
| return Symbol{}; |
| |
| case wgsl::BuiltinFn::kSign: |
| if (cfg.builtins.sign_int) { |
| auto* ty = builtin->ReturnType(); |
| if (ty->is_signed_integer_scalar_or_vector()) { |
| return builtin_polyfills.GetOrAdd(builtin, |
| [&] { return sign_int(ty); }); |
| } |
| } |
| return Symbol{}; |
| |
| case wgsl::BuiltinFn::kTextureLoad: |
| if (cfg.builtins.bgra8unorm) { |
| auto& sig = builtin->Signature(); |
| auto* tex = sig.Parameter(core::ParameterUsage::kTexture); |
| if (auto* stex = tex->Type()->As<core::type::StorageTexture>()) { |
| if (stex->texel_format() == core::TexelFormat::kBgra8Unorm) { |
| ctx.Replace(expr, [this, expr] { |
| return ctx.dst->MemberAccessor( |
| ctx.CloneWithoutTransform(expr), "bgra"); |
| }); |
| made_changes = true; |
| } |
| } |
| } |
| return Symbol{}; |
| |
| case wgsl::BuiltinFn::kTextureSampleBaseClampToEdge: |
| if (cfg.builtins.texture_sample_base_clamp_to_edge_2d_f32) { |
| auto& sig = builtin->Signature(); |
| auto* tex = sig.Parameter(core::ParameterUsage::kTexture); |
| if (auto* stex = tex->Type()->As<core::type::SampledTexture>()) { |
| if (stex->type()->Is<core::type::F32>()) { |
| return builtin_polyfills.GetOrAdd(builtin, [&] { |
| return textureSampleBaseClampToEdge_2d_f32(); |
| }); |
| } |
| } |
| } |
| return Symbol{}; |
| |
| case wgsl::BuiltinFn::kTextureStore: |
| if (cfg.builtins.bgra8unorm) { |
| auto& sig = builtin->Signature(); |
| auto* tex = sig.Parameter(core::ParameterUsage::kTexture); |
| if (auto* stex = tex->Type()->As<core::type::StorageTexture>()) { |
| if (stex->texel_format() == core::TexelFormat::kBgra8Unorm) { |
| size_t value_idx = static_cast<size_t>( |
| sig.IndexOf(core::ParameterUsage::kValue)); |
| ctx.Replace(expr, [this, expr, value_idx] { |
| tint::Vector<const Expression*, 3> args; |
| for (auto* arg : expr->args) { |
| arg = ctx.Clone(arg); |
| if (args.Length() == value_idx) { // value |
| arg = ctx.dst->MemberAccessor(arg, "bgra"); |
| } |
| args.Push(arg); |
| } |
| return ctx.dst->Call( |
| tint::ToString(wgsl::BuiltinFn::kTextureStore), |
| std::move(args)); |
| }); |
| made_changes = true; |
| } |
| } |
| } |
| return Symbol{}; |
| |
| case wgsl::BuiltinFn::kQuantizeToF16: |
| if (cfg.builtins.quantize_to_vec_f16) { |
| if (auto* vec = builtin->ReturnType()->As<core::type::Vector>()) { |
| return builtin_polyfills.GetOrAdd( |
| builtin, [&] { return quantizeToF16(vec); }); |
| } |
| } |
| return Symbol{}; |
| |
| case wgsl::BuiltinFn::kWorkgroupUniformLoad: |
| if (cfg.builtins.workgroup_uniform_load) { |
| return builtin_polyfills.GetOrAdd(builtin, [&] { |
| return workgroupUniformLoad(builtin->ReturnType()); |
| }); |
| } |
| return Symbol{}; |
| |
| case wgsl::BuiltinFn::kDot4I8Packed: { |
| if (cfg.builtins.dot_4x8_packed) { |
| return builtin_polyfills.GetOrAdd(builtin, |
| [&] { return Dot4I8Packed(); }); |
| } |
| return Symbol{}; |
| } |
| |
| case wgsl::BuiltinFn::kDot4U8Packed: { |
| if (cfg.builtins.dot_4x8_packed) { |
| return builtin_polyfills.GetOrAdd(builtin, |
| [&] { return Dot4U8Packed(); }); |
| } |
| return Symbol{}; |
| } |
| |
| case wgsl::BuiltinFn::kPack4XI8: { |
| if (cfg.builtins.pack_unpack_4x8) { |
| return builtin_polyfills.GetOrAdd(builtin, [&] { return Pack4xI8(); }); |
| } |
| return Symbol{}; |
| } |
| |
| case wgsl::BuiltinFn::kPack4XU8: { |
| if (cfg.builtins.pack_unpack_4x8) { |
| return builtin_polyfills.GetOrAdd(builtin, [&] { return Pack4xU8(); }); |
| } |
| return Symbol{}; |
| } |
| |
| case wgsl::BuiltinFn::kPack4XI8Clamp: { |
| if (cfg.builtins.pack_unpack_4x8) { |
| return builtin_polyfills.GetOrAdd(builtin, |
| [&] { return Pack4xI8Clamp(); }); |
| } |
| return Symbol{}; |
| } |
| |
| case wgsl::BuiltinFn::kPack4XU8Clamp: { |
| if (cfg.builtins.pack_4xu8_clamp) { |
| return builtin_polyfills.GetOrAdd(builtin, |
| [&] { return Pack4xU8Clamp(); }); |
| } |
| return Symbol{}; |
| } |
| |
| case wgsl::BuiltinFn::kUnpack4XI8: { |
| if (cfg.builtins.pack_unpack_4x8) { |
| return builtin_polyfills.GetOrAdd(builtin, |
| [&] { return Unpack4xI8(); }); |
| } |
| return Symbol{}; |
| } |
| |
| case wgsl::BuiltinFn::kUnpack4XU8: { |
| if (cfg.builtins.pack_unpack_4x8) { |
| return builtin_polyfills.GetOrAdd(builtin, |
| [&] { return Unpack4xU8(); }); |
| } |
| return Symbol{}; |
| } |
| |
| default: |
| return Symbol{}; |
| } |
| }, |
| [&](const sem::ValueConversion* conv) { |
| if (cfg.builtins.conv_f32_to_iu32) { |
| auto* src_ty = conv->Source(); |
| if (tint::Is<core::type::F32>(src_ty->Elements(src_ty).type)) { |
| auto* dst_ty = conv->Target(); |
| if (tint::IsAnyOf<core::type::I32, core::type::U32>( |
| dst_ty->Elements(dst_ty).type)) { |
| return f32_conv_polyfills.GetOrAdd(dst_ty, [&] { // |
| return ConvF32ToIU32(src_ty, dst_ty); |
| }); |
| } |
| } |
| } |
| return Symbol{}; |
| }); |
| |
| if (fn.IsValid()) { |
| ctx.Replace(call->Declaration(), |
| [this, fn, expr] { return ctx.dst->Call(fn, ctx.Clone(expr->args)); }); |
| made_changes = true; |
| } |
| } |
| }; |
| |
| BuiltinPolyfill::BuiltinPolyfill() = default; |
| |
| BuiltinPolyfill::~BuiltinPolyfill() = default; |
| |
| Transform::ApplyResult BuiltinPolyfill::Apply(const Program& src, |
| const DataMap& data, |
| DataMap&) const { |
| auto* cfg = data.Get<Config>(); |
| if (!cfg) { |
| return SkipTransform; |
| } |
| return State{src, *cfg}.Run(); |
| } |
| |
| BuiltinPolyfill::Config::Config() = default; |
| BuiltinPolyfill::Config::Config(const Builtins& b) : builtins(b) {} |
| BuiltinPolyfill::Config::Config(const Config&) = default; |
| BuiltinPolyfill::Config::~Config() = default; |
| |
| } // namespace tint::ast::transform |
