ebiten/internal/shader/expr.go
2024-02-25 21:21:27 +09:00

1207 lines
39 KiB
Go

// Copyright 2020 The Ebiten Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package shader
import (
"fmt"
"go/ast"
gconstant "go/constant"
"go/token"
"regexp"
"strconv"
"strings"
"github.com/hajimehoshi/ebiten/v2/internal/shaderir"
)
func canTruncateToInteger(v gconstant.Value) bool {
return gconstant.ToInt(v).Kind() != gconstant.Unknown
}
func canTruncateToFloat(v gconstant.Value) bool {
return gconstant.ToFloat(v).Kind() != gconstant.Unknown
}
var textureVariableRe = regexp.MustCompile(`\A__t(\d+)\z`)
func (cs *compileState) parseExpr(block *block, fname string, expr ast.Expr, markLocalVariableUsed bool) ([]shaderir.Expr, []shaderir.Type, []shaderir.Stmt, bool) {
switch e := expr.(type) {
case *ast.BasicLit:
switch e.Kind {
case token.INT:
// The type is not determined yet.
return []shaderir.Expr{
{
Type: shaderir.NumberExpr,
Const: gconstant.MakeFromLiteral(e.Value, e.Kind, 0),
},
}, []shaderir.Type{{}}, nil, true
case token.FLOAT:
// The type is not determined yet.
return []shaderir.Expr{
{
Type: shaderir.NumberExpr,
Const: gconstant.MakeFromLiteral(e.Value, e.Kind, 0),
},
}, []shaderir.Type{{}}, nil, true
default:
cs.addError(e.Pos(), fmt.Sprintf("literal not implemented: %#v", e))
}
case *ast.BinaryExpr:
var stmts []shaderir.Stmt
// Prase LHS first for the order of the statements.
lhs, ts, ss, ok := cs.parseExpr(block, fname, e.X, markLocalVariableUsed)
if !ok {
return nil, nil, nil, false
}
if len(lhs) != 1 {
cs.addError(e.Pos(), fmt.Sprintf("multiple-value context is not available at a binary operator: %s", e.X))
return nil, nil, nil, false
}
stmts = append(stmts, ss...)
lhst := ts[0]
rhs, ts, ss, ok := cs.parseExpr(block, fname, e.Y, markLocalVariableUsed)
if !ok {
return nil, nil, nil, false
}
if len(rhs) != 1 {
cs.addError(e.Pos(), fmt.Sprintf("multiple-value context is not available at a binary operator: %s", e.Y))
return nil, nil, nil, false
}
stmts = append(stmts, ss...)
rhst := ts[0]
op := e.Op
// https://pkg.go.dev/go/constant/#BinaryOp
// "To force integer division of Int operands, use op == token.QUO_ASSIGN instead of
// token.QUO; the result is guaranteed to be Int in this case."
if op == token.QUO && lhs[0].Const != nil && lhs[0].Const.Kind() == gconstant.Int && rhs[0].Const != nil && rhs[0].Const.Kind() == gconstant.Int {
op = token.QUO_ASSIGN
}
op2, ok := shaderir.OpFromToken(e.Op, lhst, rhst)
if !ok {
cs.addError(e.Pos(), fmt.Sprintf("unexpected operator: %s", e.Op))
return nil, nil, nil, false
}
// Resolve untyped constants.
l, r, ok := shaderir.ResolveUntypedConstsForBinaryOp(lhs[0].Const, rhs[0].Const, lhst, rhst)
if !ok {
// TODO: Show a better type name for untyped constants.
cs.addError(e.Pos(), fmt.Sprintf("types don't match: %s %s %s", lhst.String(), op, rhst.String()))
return nil, nil, nil, false
}
lhs[0].Const, rhs[0].Const = l, r
// If either is typed, resolve the other type.
// If both are untyped, keep them untyped.
if lhst.Main != shaderir.None || rhst.Main != shaderir.None {
if lhs[0].Const != nil {
switch lhs[0].Const.Kind() {
case gconstant.Float:
lhst = shaderir.Type{Main: shaderir.Float}
case gconstant.Int:
lhst = shaderir.Type{Main: shaderir.Int}
case gconstant.Bool:
lhst = shaderir.Type{Main: shaderir.Bool}
}
}
if rhs[0].Const != nil {
switch rhs[0].Const.Kind() {
case gconstant.Float:
rhst = shaderir.Type{Main: shaderir.Float}
case gconstant.Int:
rhst = shaderir.Type{Main: shaderir.Int}
case gconstant.Bool:
rhst = shaderir.Type{Main: shaderir.Bool}
}
}
}
t, ok := shaderir.TypeFromBinaryOp(op2, lhst, rhst, lhs[0].Const, rhs[0].Const)
if !ok {
// TODO: Show a better type name for untyped constants.
cs.addError(e.Pos(), fmt.Sprintf("types don't match: %s %s %s", lhst.String(), op, rhst.String()))
return nil, nil, nil, false
}
if lhs[0].Const != nil && rhs[0].Const != nil {
var v gconstant.Value
switch op {
case token.LAND, token.LOR:
b := gconstant.BoolVal(gconstant.BinaryOp(lhs[0].Const, op, rhs[0].Const))
v = gconstant.MakeBool(b)
case token.EQL, token.NEQ, token.LSS, token.LEQ, token.GTR, token.GEQ:
v = gconstant.MakeBool(gconstant.Compare(lhs[0].Const, op, rhs[0].Const))
default:
v = gconstant.BinaryOp(lhs[0].Const, op, rhs[0].Const)
}
return []shaderir.Expr{
{
Type: shaderir.NumberExpr,
Const: v,
},
}, []shaderir.Type{t}, stmts, true
}
return []shaderir.Expr{
{
Type: shaderir.Binary,
Op: op2,
Exprs: []shaderir.Expr{lhs[0], rhs[0]},
},
}, []shaderir.Type{t}, stmts, true
case *ast.CallExpr:
var (
callee shaderir.Expr
args []shaderir.Expr
argts []shaderir.Type
stmts []shaderir.Stmt
)
// Parse the argument first for the order of the statements.
for _, a := range e.Args {
es, ts, ss, ok := cs.parseExpr(block, fname, a, markLocalVariableUsed)
if !ok {
return nil, nil, nil, false
}
if len(es) > 1 && len(e.Args) > 1 {
cs.addError(e.Pos(), fmt.Sprintf("single-value context and multiple-value context cannot be mixed: %s", e.Fun))
return nil, nil, nil, false
}
for _, expr := range es {
if expr.Type == shaderir.FunctionExpr {
cs.addError(e.Pos(), fmt.Sprintf("function name cannot be an argument: %s", e.Fun))
return nil, nil, nil, false
}
}
args = append(args, es...)
argts = append(argts, ts...)
stmts = append(stmts, ss...)
}
// TODO: When len(ss) is not 0?
es, _, ss, ok := cs.parseExpr(block, fname, e.Fun, markLocalVariableUsed)
if !ok {
return nil, nil, nil, false
}
if len(es) != 1 {
cs.addError(e.Pos(), fmt.Sprintf("multiple-value context is not available at a callee: %s", e.Fun))
return nil, nil, nil, false
}
callee = es[0]
stmts = append(stmts, ss...)
// For built-in functions, we can call this in this position. Return an expression for the function
// call.
if callee.Type == shaderir.BuiltinFuncExpr {
// Process compile-time evaluations.
switch callee.BuiltinFunc {
case shaderir.Len, shaderir.Cap:
if len(args) != 1 {
cs.addError(e.Pos(), fmt.Sprintf("number of %s's arguments must be 1 but %d", callee.BuiltinFunc, len(args)))
return nil, nil, nil, false
}
if argts[0].Main != shaderir.Array {
cs.addError(e.Pos(), fmt.Sprintf("%s takes an array but %s", callee.BuiltinFunc, argts[0].String()))
return nil, nil, nil, false
}
return []shaderir.Expr{
{
Type: shaderir.NumberExpr,
Const: gconstant.MakeInt64(int64(argts[0].Length)),
},
}, []shaderir.Type{{Main: shaderir.Int}}, stmts, true
case shaderir.BoolF:
if len(args) == 1 && args[0].Const != nil {
if args[0].Const.Kind() != gconstant.Bool {
cs.addError(e.Pos(), fmt.Sprintf("cannot convert %s to type bool", args[0].Const.String()))
return nil, nil, nil, false
}
return []shaderir.Expr{
{
Type: shaderir.NumberExpr,
Const: args[0].Const,
},
}, []shaderir.Type{{Main: shaderir.Bool}}, stmts, true
}
case shaderir.IntF:
if len(args) == 1 && args[0].Const != nil {
// For constants, a cast-like function doesn't work as a cast.
// For example, `int(1.1)` is invalid.
v := gconstant.ToInt(args[0].Const)
if v.Kind() == gconstant.Unknown {
cs.addError(e.Pos(), fmt.Sprintf("cannot convert %s to type int", args[0].Const.String()))
return nil, nil, nil, false
}
return []shaderir.Expr{
{
Type: shaderir.NumberExpr,
Const: v,
},
}, []shaderir.Type{{Main: shaderir.Int}}, stmts, true
}
case shaderir.FloatF:
if len(args) == 1 && args[0].Const != nil {
v := gconstant.ToFloat(args[0].Const)
if v.Kind() == gconstant.Unknown {
cs.addError(e.Pos(), fmt.Sprintf("cannot convert %s to type float", args[0].Const.String()))
return nil, nil, nil, false
}
return []shaderir.Expr{
{
Type: shaderir.NumberExpr,
Const: v,
},
}, []shaderir.Type{{Main: shaderir.Float}}, stmts, true
}
}
// Process the expression as a regular function call.
var t shaderir.Type
switch callee.BuiltinFunc {
case shaderir.BoolF:
if err := checkArgsForBoolBuiltinFunc(args, argts); err != nil {
cs.addError(e.Pos(), err.Error())
return nil, nil, nil, false
}
t = shaderir.Type{Main: shaderir.Bool}
case shaderir.IntF:
if err := checkArgsForIntBuiltinFunc(args, argts); err != nil {
cs.addError(e.Pos(), err.Error())
return nil, nil, nil, false
}
t = shaderir.Type{Main: shaderir.Int}
case shaderir.FloatF:
if err := checkArgsForFloatBuiltinFunc(args, argts); err != nil {
cs.addError(e.Pos(), err.Error())
return nil, nil, nil, false
}
t = shaderir.Type{Main: shaderir.Float}
case shaderir.Vec2F:
if err := checkArgsForVec2BuiltinFunc(args, argts); err != nil {
cs.addError(e.Pos(), err.Error())
return nil, nil, nil, false
}
for i := range args {
if args[i].Const == nil {
continue
}
args[i].Const = gconstant.ToFloat(args[i].Const)
argts[i] = shaderir.Type{Main: shaderir.Float}
}
t = shaderir.Type{Main: shaderir.Vec2}
case shaderir.Vec3F:
if err := checkArgsForVec3BuiltinFunc(args, argts); err != nil {
cs.addError(e.Pos(), err.Error())
return nil, nil, nil, false
}
for i := range args {
if args[i].Const == nil {
continue
}
args[i].Const = gconstant.ToFloat(args[i].Const)
argts[i] = shaderir.Type{Main: shaderir.Float}
}
t = shaderir.Type{Main: shaderir.Vec3}
case shaderir.Vec4F:
if err := checkArgsForVec4BuiltinFunc(args, argts); err != nil {
cs.addError(e.Pos(), err.Error())
return nil, nil, nil, false
}
for i := range args {
if args[i].Const == nil {
continue
}
args[i].Const = gconstant.ToFloat(args[i].Const)
argts[i] = shaderir.Type{Main: shaderir.Float}
}
t = shaderir.Type{Main: shaderir.Vec4}
case shaderir.IVec2F:
if err := checkArgsForIVec2BuiltinFunc(args, argts); err != nil {
cs.addError(e.Pos(), err.Error())
return nil, nil, nil, false
}
t = shaderir.Type{Main: shaderir.IVec2}
case shaderir.IVec3F:
if err := checkArgsForIVec3BuiltinFunc(args, argts); err != nil {
cs.addError(e.Pos(), err.Error())
return nil, nil, nil, false
}
t = shaderir.Type{Main: shaderir.IVec3}
case shaderir.IVec4F:
if err := checkArgsForIVec4BuiltinFunc(args, argts); err != nil {
cs.addError(e.Pos(), err.Error())
return nil, nil, nil, false
}
t = shaderir.Type{Main: shaderir.IVec4}
case shaderir.Mat2F:
if err := checkArgsForMat2BuiltinFunc(args, argts); err != nil {
cs.addError(e.Pos(), err.Error())
return nil, nil, nil, false
}
for i := range args {
if args[i].Const == nil {
continue
}
args[i].Const = gconstant.ToFloat(args[i].Const)
argts[i] = shaderir.Type{Main: shaderir.Float}
}
t = shaderir.Type{Main: shaderir.Mat2}
case shaderir.Mat3F:
if err := checkArgsForMat3BuiltinFunc(args, argts); err != nil {
cs.addError(e.Pos(), err.Error())
return nil, nil, nil, false
}
for i := range args {
if args[i].Const == nil {
continue
}
args[i].Const = gconstant.ToFloat(args[i].Const)
argts[i] = shaderir.Type{Main: shaderir.Float}
}
t = shaderir.Type{Main: shaderir.Mat3}
case shaderir.Mat4F:
if err := checkArgsForMat4BuiltinFunc(args, argts); err != nil {
cs.addError(e.Pos(), err.Error())
return nil, nil, nil, false
}
for i := range args {
if args[i].Const == nil {
continue
}
args[i].Const = gconstant.ToFloat(args[i].Const)
argts[i] = shaderir.Type{Main: shaderir.Float}
}
t = shaderir.Type{Main: shaderir.Mat4}
case shaderir.TexelAt:
if len(args) != 2 {
cs.addError(e.Pos(), fmt.Sprintf("number of %s's arguments must be 2 but %d", callee.BuiltinFunc, len(args)))
return nil, nil, nil, false
}
if argts[0].Main != shaderir.Texture {
cs.addError(e.Pos(), fmt.Sprintf("cannot use %s as texture value in argument to %s", argts[0].String(), callee.BuiltinFunc))
return nil, nil, nil, false
}
if argts[1].Main != shaderir.Vec2 {
cs.addError(e.Pos(), fmt.Sprintf("cannot use %s as vec2 value in argument to %s", argts[1].String(), callee.BuiltinFunc))
return nil, nil, nil, false
}
t = shaderir.Type{Main: shaderir.Vec4}
case shaderir.DiscardF:
if len(args) != 0 {
cs.addError(e.Pos(), fmt.Sprintf("number of %s's arguments must be 0 but %d", callee.BuiltinFunc, len(args)))
return nil, nil, nil, false
}
if fname != cs.fragmentEntry {
cs.addError(e.Pos(), fmt.Sprintf("discard is available only in %s", cs.fragmentEntry))
return nil, nil, nil, false
}
stmts = append(stmts, shaderir.Stmt{
Type: shaderir.Discard,
})
return nil, nil, stmts, true
case shaderir.Clamp, shaderir.Mix, shaderir.Smoothstep, shaderir.Faceforward, shaderir.Refract:
// 3 arguments
if len(args) != 3 {
cs.addError(e.Pos(), fmt.Sprintf("number of %s's arguments must be 3 but %d", callee.BuiltinFunc, len(args)))
return nil, nil, nil, false
}
switch callee.BuiltinFunc {
case shaderir.Clamp:
if kind, allConsts := resolveConstKind(args, argts); allConsts {
switch kind {
case gconstant.Unknown:
cs.addError(e.Pos(), fmt.Sprintf("%s's arguments don't match: %s, %s, and %s", callee.BuiltinFunc, argts[0].String(), argts[1].String(), argts[2].String()))
return nil, nil, nil, false
case gconstant.Int:
for i, arg := range args {
v := gconstant.ToInt(arg.Const)
if v.Kind() == gconstant.Unknown {
cs.addError(e.Pos(), fmt.Sprintf("cannot convert %s to type int", arg.Const.String()))
return nil, nil, nil, false
}
args[i].Const = gconstant.ToInt(args[i].Const)
argts[i] = shaderir.Type{Main: shaderir.Int}
}
case gconstant.Float:
for i, arg := range args {
v := gconstant.ToFloat(arg.Const)
if v.Kind() == gconstant.Unknown {
cs.addError(e.Pos(), fmt.Sprintf("cannot convert %s to type float", arg.Const.String()))
return nil, nil, nil, false
}
args[i].Const = gconstant.ToFloat(args[i].Const)
argts[i] = shaderir.Type{Main: shaderir.Float}
}
}
}
if argts[0].IsIntVector() {
for i := 1; i < 3; i++ {
if args[i].Const != nil {
v := gconstant.ToInt(args[i].Const)
if v.Kind() == gconstant.Unknown {
cs.addError(e.Pos(), fmt.Sprintf("cannot convert %s to type int", args[i].Const.String()))
return nil, nil, nil, false
}
args[i].Const = v
argts[i] = shaderir.Type{Main: shaderir.Int}
}
}
}
if argts[0].IsFloatVector() {
for i := 1; i < 3; i++ {
if args[i].Const != nil {
v := gconstant.ToFloat(args[i].Const)
if v.Kind() == gconstant.Unknown {
cs.addError(e.Pos(), fmt.Sprintf("cannot convert %s to type float", args[i].Const.String()))
return nil, nil, nil, false
}
args[i].Const = v
argts[i] = shaderir.Type{Main: shaderir.Float}
}
}
}
default:
for i := range args {
// If the argument is a non-typed constant value, treat this as a float value (#1874).
if args[i].Const != nil && argts[i].Main == shaderir.None && gconstant.ToFloat(args[i].Const).Kind() != gconstant.Unknown {
args[i].Const = gconstant.ToFloat(args[i].Const)
argts[i] = shaderir.Type{Main: shaderir.Float}
}
}
}
for i := range args {
switch callee.BuiltinFunc {
case shaderir.Clamp:
if argts[i].Main != shaderir.Float && !argts[i].IsFloatVector() && argts[i].Main != shaderir.Int && !argts[i].IsIntVector() {
cs.addError(e.Pos(), fmt.Sprintf("cannot use %s as float, vecN, int, or ivecN value in argument to %s", argts[i].String(), callee.BuiltinFunc))
return nil, nil, nil, false
}
default:
if argts[i].Main != shaderir.Float && !argts[i].IsFloatVector() {
cs.addError(e.Pos(), fmt.Sprintf("cannot use %s as float, vec2, vec3, or vec4 value in argument to %s", argts[i].String(), callee.BuiltinFunc))
return nil, nil, nil, false
}
}
}
switch callee.BuiltinFunc {
case shaderir.Clamp:
if !((argts[0].Equal(&argts[1]) && argts[0].Equal(&argts[2])) ||
(argts[0].IsFloatVector() && argts[1].Main == shaderir.Float && argts[2].Main == shaderir.Float) ||
(argts[0].IsIntVector() && argts[1].Main == shaderir.Int && argts[2].Main == shaderir.Int)) {
cs.addError(e.Pos(), fmt.Sprintf("the second and the third arguments for %s must equal to the first argument %s or float or int but %s and %s", callee.BuiltinFunc, argts[0].String(), argts[1].String(), argts[2].String()))
return nil, nil, nil, false
}
case shaderir.Mix:
if !argts[0].Equal(&argts[1]) {
cs.addError(e.Pos(), fmt.Sprintf("%s and %s don't match in argument to %s", argts[0].String(), argts[1].String(), callee.BuiltinFunc))
return nil, nil, nil, false
}
if !argts[0].Equal(&argts[2]) && argts[2].Main != shaderir.Float {
cs.addError(e.Pos(), fmt.Sprintf("the third arguments for %s must equal to the first/second argument %s or float but %s", callee.BuiltinFunc, argts[0].String(), argts[2].String()))
return nil, nil, nil, false
}
case shaderir.Smoothstep:
if (!argts[0].Equal(&argts[1]) || !argts[0].Equal(&argts[2])) && (argts[0].Main != shaderir.Float || argts[1].Main != shaderir.Float) {
cs.addError(e.Pos(), fmt.Sprintf("the first and the second arguments for %s must equal to the third argument %s or float but %s and %s", callee.BuiltinFunc, argts[2].String(), argts[0].String(), argts[1].String()))
return nil, nil, nil, false
}
case shaderir.Refract:
if !argts[0].Equal(&argts[1]) {
cs.addError(e.Pos(), fmt.Sprintf("%s and %s don't match in argument to %s", argts[0].String(), argts[1].String(), callee.BuiltinFunc))
return nil, nil, nil, false
}
if argts[2].Main != shaderir.Float {
cs.addError(e.Pos(), fmt.Sprintf("cannot use %s as float value in argument to %s", argts[2].String(), callee.BuiltinFunc))
return nil, nil, nil, false
}
default:
if !argts[0].Equal(&argts[1]) || !argts[0].Equal(&argts[2]) {
cs.addError(e.Pos(), fmt.Sprintf("all the argument types for %s must be the same but %s, %s, and %s", callee.BuiltinFunc, argts[0].String(), argts[1].String(), argts[2].String()))
return nil, nil, nil, false
}
}
switch callee.BuiltinFunc {
case shaderir.Smoothstep:
t = argts[2]
default:
t = argts[0]
}
case shaderir.Atan2, shaderir.Pow, shaderir.Mod, shaderir.Min, shaderir.Max, shaderir.Step, shaderir.Distance, shaderir.Dot, shaderir.Cross, shaderir.Reflect:
// 2 arguments
if len(args) != 2 {
cs.addError(e.Pos(), fmt.Sprintf("number of %s's arguments must be 2 but %d", callee.BuiltinFunc, len(args)))
return nil, nil, nil, false
}
switch callee.BuiltinFunc {
case shaderir.Min, shaderir.Max:
if kind, allConsts := resolveConstKind(args, argts); allConsts {
switch kind {
case gconstant.Unknown:
cs.addError(e.Pos(), fmt.Sprintf("%s's arguments don't match: %s and %s", callee.BuiltinFunc, argts[0].String(), argts[1].String()))
return nil, nil, nil, false
case gconstant.Int:
for i, arg := range args {
v := gconstant.ToInt(arg.Const)
if v.Kind() == gconstant.Unknown {
cs.addError(e.Pos(), fmt.Sprintf("cannot convert %s to type int", arg.Const.String()))
return nil, nil, nil, false
}
args[i].Const = gconstant.ToInt(args[i].Const)
argts[i] = shaderir.Type{Main: shaderir.Int}
}
case gconstant.Float:
for i, arg := range args {
v := gconstant.ToFloat(arg.Const)
if v.Kind() == gconstant.Unknown {
cs.addError(e.Pos(), fmt.Sprintf("cannot convert %s to type float", arg.Const.String()))
return nil, nil, nil, false
}
args[i].Const = gconstant.ToFloat(args[i].Const)
argts[i] = shaderir.Type{Main: shaderir.Float}
}
}
}
if argts[0].IsIntVector() && args[1].Const != nil {
v := gconstant.ToInt(args[1].Const)
if v.Kind() == gconstant.Unknown {
cs.addError(e.Pos(), fmt.Sprintf("cannot convert %s to type int", args[1].Const.String()))
return nil, nil, nil, false
}
args[1].Const = v
argts[1] = shaderir.Type{Main: shaderir.Int}
}
if argts[0].IsFloatVector() && args[1].Const != nil {
v := gconstant.ToFloat(args[1].Const)
if v.Kind() == gconstant.Unknown {
cs.addError(e.Pos(), fmt.Sprintf("cannot convert %s to type float", args[1].Const.String()))
return nil, nil, nil, false
}
args[1].Const = v
argts[1] = shaderir.Type{Main: shaderir.Float}
}
default:
for i := range args {
if args[i].Const != nil && argts[i].Main == shaderir.None {
// If the argument is a non-typed constant value, treat this as a float value (#1874).
if gconstant.ToFloat(args[i].Const).Kind() != gconstant.Unknown {
args[i].Const = gconstant.ToFloat(args[i].Const)
argts[i] = shaderir.Type{Main: shaderir.Float}
}
}
}
}
for i := range args {
switch callee.BuiltinFunc {
case shaderir.Min, shaderir.Max:
if argts[i].Main != shaderir.Float && !argts[i].IsFloatVector() && argts[i].Main != shaderir.Int && !argts[i].IsIntVector() {
cs.addError(e.Pos(), fmt.Sprintf("cannot use %s as float, vecN, int, or ivecN value in argument to %s", argts[i].String(), callee.BuiltinFunc))
return nil, nil, nil, false
}
default:
if argts[i].Main != shaderir.Float && !argts[i].IsFloatVector() {
cs.addError(e.Pos(), fmt.Sprintf("cannot use %s as float, vec2, vec3, or vec4 value in argument to %s", argts[i].String(), callee.BuiltinFunc))
return nil, nil, nil, false
}
}
}
switch callee.BuiltinFunc {
case shaderir.Mod:
if !argts[0].Equal(&argts[1]) && argts[1].Main != shaderir.Float {
cs.addError(e.Pos(), fmt.Sprintf("the second argument for %s must equal to the first argument %s or float but %s", callee.BuiltinFunc, argts[0].String(), argts[1].String()))
return nil, nil, nil, false
}
case shaderir.Min, shaderir.Max:
if !(argts[0].Equal(&argts[1]) || (argts[0].IsFloatVector() && argts[1].Main == shaderir.Float) || (argts[0].IsIntVector() && argts[1].Main == shaderir.Int)) {
cs.addError(e.Pos(), fmt.Sprintf("the second argument for %s must equal to the first argument %s or float or int but %s", callee.BuiltinFunc, argts[0].String(), argts[1].String()))
return nil, nil, nil, false
}
case shaderir.Step:
if !argts[0].Equal(&argts[1]) && argts[0].Main != shaderir.Float {
cs.addError(e.Pos(), fmt.Sprintf("the first argument for %s must equal to the second argument %s or float but %s", callee.BuiltinFunc, argts[1].String(), argts[0].String()))
return nil, nil, nil, false
}
case shaderir.Cross:
for i := range argts {
if argts[i].Main != shaderir.Vec3 {
cs.addError(e.Pos(), fmt.Sprintf("cannot use %s as vec3 value in argument to %s", argts[i].String(), callee.BuiltinFunc))
return nil, nil, nil, false
}
}
default:
if !argts[0].Equal(&argts[1]) {
cs.addError(e.Pos(), fmt.Sprintf("%s and %s don't match in argument to %s", argts[0].String(), argts[1].String(), callee.BuiltinFunc))
return nil, nil, nil, false
}
}
switch callee.BuiltinFunc {
case shaderir.Distance, shaderir.Dot:
t = shaderir.Type{Main: shaderir.Float}
case shaderir.Step:
t = argts[1]
default:
t = argts[0]
}
default:
// 1 argument
if len(args) != 1 {
cs.addError(e.Pos(), fmt.Sprintf("number of %s's arguments must be 1 but %d", callee.BuiltinFunc, len(args)))
return nil, nil, nil, false
}
if args[0].Const != nil && argts[0].Main == shaderir.None {
switch callee.BuiltinFunc {
case shaderir.Abs, shaderir.Sign:
if args[0].Const.Kind() == gconstant.Int {
argts[0] = shaderir.Type{Main: shaderir.Int}
}
if args[0].Const.Kind() == gconstant.Float {
argts[0] = shaderir.Type{Main: shaderir.Float}
}
default:
// If the argument is a non-typed constant value, treat this as a float value (#1874).
if gconstant.ToFloat(args[0].Const).Kind() != gconstant.Unknown {
args[0].Const = gconstant.ToFloat(args[0].Const)
argts[0] = shaderir.Type{Main: shaderir.Float}
}
}
}
switch callee.BuiltinFunc {
case shaderir.Transpose:
if !argts[0].IsMatrix() {
cs.addError(e.Pos(), fmt.Sprintf("cannot use %s as mat2, mat3, or mat4 value in argument to %s", argts[0].String(), callee.BuiltinFunc))
return nil, nil, nil, false
}
case shaderir.Abs, shaderir.Sign:
if argts[0].Main != shaderir.Float && !argts[0].IsFloatVector() && argts[0].Main != shaderir.Int && !argts[0].IsIntVector() {
cs.addError(e.Pos(), fmt.Sprintf("cannot use %s as float, vecN, int, or ivenN value in argument to %s", argts[0].String(), callee.BuiltinFunc))
return nil, nil, nil, false
}
default:
if argts[0].Main != shaderir.Float && !argts[0].IsFloatVector() {
cs.addError(e.Pos(), fmt.Sprintf("cannot use %s as float, vec2, vec3, or vec4 value in argument to %s", argts[0].String(), callee.BuiltinFunc))
return nil, nil, nil, false
}
}
if callee.BuiltinFunc == shaderir.Length {
t = shaderir.Type{Main: shaderir.Float}
} else {
t = argts[0]
}
}
return []shaderir.Expr{
{
Type: shaderir.Call,
Exprs: append([]shaderir.Expr{callee}, args...),
},
}, []shaderir.Type{t}, stmts, true
}
if callee.Type != shaderir.FunctionExpr {
cs.addError(e.Pos(), fmt.Sprintf("function callee must be a function name but %s", e.Fun))
return nil, nil, nil, false
}
f := cs.funcs[callee.Index]
if len(f.ir.InParams) < len(args) {
cs.addError(e.Pos(), fmt.Sprintf("too many arguments in call to %s", e.Fun))
return nil, nil, nil, false
}
if len(f.ir.InParams) > len(args) {
cs.addError(e.Pos(), fmt.Sprintf("not enough arguments in call to %s", e.Fun))
return nil, nil, nil, false
}
for i, p := range f.ir.InParams {
if !canAssign(&p, &argts[i], args[i].Const) {
cs.addError(e.Pos(), fmt.Sprintf("cannot use type %s as type %s in argument", argts[i].String(), p.String()))
return nil, nil, nil, false
}
if args[i].Const != nil {
switch p.Main {
case shaderir.Int:
args[i].Const = gconstant.ToInt(args[i].Const)
argts[i] = shaderir.Type{Main: shaderir.Int}
case shaderir.Float:
args[i].Const = gconstant.ToFloat(args[i].Const)
argts[i] = shaderir.Type{Main: shaderir.Float}
}
}
}
var outParams []int
for _, p := range f.ir.OutParams {
idx := block.totalLocalVariableCount()
block.vars = append(block.vars, variable{
typ: p,
})
args = append(args, shaderir.Expr{
Type: shaderir.LocalVariable,
Index: idx,
})
outParams = append(outParams, idx)
}
if t := f.ir.Return; t.Main != shaderir.None {
if len(outParams) != 0 {
cs.addError(e.Pos(), fmt.Sprintf("a function returning value cannot have out-params so far: %s", e.Fun))
return nil, nil, nil, false
}
// The actual expression here is just a local variable that includes the result of the
// function call.
return []shaderir.Expr{
{
Type: shaderir.Call,
Exprs: append([]shaderir.Expr{callee}, args...),
},
}, []shaderir.Type{t}, stmts, true
}
// Even if the function doesn't return anything, calling the function should be done earlier to keep
// the evaluation order.
stmts = append(stmts, shaderir.Stmt{
Type: shaderir.ExprStmt,
Exprs: []shaderir.Expr{
{
Type: shaderir.Call,
Exprs: append([]shaderir.Expr{callee}, args...),
},
},
})
if len(outParams) == 0 {
// TODO: Is this an error?
}
// These local-variable expressions are used for an outside function callers.
var exprs []shaderir.Expr
for _, p := range outParams {
exprs = append(exprs, shaderir.Expr{
Type: shaderir.LocalVariable,
Index: p,
})
}
return exprs, f.ir.OutParams, stmts, true
case *ast.Ident:
if e.Name == "_" {
// In the context where a local variable is marked as used, any expressions must have its
// meaning. Then, a blank identifier is not available there.
if markLocalVariableUsed {
cs.addError(e.Pos(), "cannot use _ as value")
return nil, nil, nil, false
}
return []shaderir.Expr{
{
Type: shaderir.Blank,
},
}, []shaderir.Type{{}}, nil, true
}
if i, t, ok := block.findLocalVariable(e.Name, markLocalVariableUsed); ok {
return []shaderir.Expr{
{
Type: shaderir.LocalVariable,
Index: i,
},
}, []shaderir.Type{t}, nil, true
}
if c, ok := block.findConstant(e.Name); ok {
return []shaderir.Expr{
{
Type: shaderir.NumberExpr,
Const: c.value,
},
}, []shaderir.Type{c.typ}, nil, true
}
if i, ok := cs.findFunction(e.Name); ok {
return []shaderir.Expr{
{
Type: shaderir.FunctionExpr,
Index: i,
},
}, nil, nil, true
}
if i, ok := cs.findUniformVariable(e.Name); ok {
return []shaderir.Expr{
{
Type: shaderir.UniformVariable,
Index: i,
},
}, []shaderir.Type{cs.ir.Uniforms[i]}, nil, true
}
if f, ok := shaderir.ParseBuiltinFunc(e.Name); ok {
return []shaderir.Expr{
{
Type: shaderir.BuiltinFuncExpr,
BuiltinFunc: f,
},
}, nil, nil, true
}
if m := textureVariableRe.FindStringSubmatch(e.Name); m != nil {
i, _ := strconv.Atoi(m[1])
return []shaderir.Expr{
{
Type: shaderir.TextureVariable,
Index: i,
},
}, []shaderir.Type{{Main: shaderir.Texture}}, nil, true
}
if e.Name == "true" || e.Name == "false" {
return []shaderir.Expr{
{
Type: shaderir.NumberExpr,
Const: gconstant.MakeBool(e.Name == "true"),
},
}, []shaderir.Type{{Main: shaderir.Bool}}, nil, true
}
cs.addError(e.Pos(), fmt.Sprintf("unexpected identifier: %s", e.Name))
case *ast.ParenExpr:
return cs.parseExpr(block, fname, e.X, markLocalVariableUsed)
case *ast.SelectorExpr:
exprs, types, stmts, ok := cs.parseExpr(block, fname, e.X, true)
if !ok {
return nil, nil, nil, false
}
if len(exprs) != 1 {
cs.addError(e.Pos(), fmt.Sprintf("multiple-value context is not available at a selector: %s", e.X))
return nil, nil, nil, false
}
if !isValidSwizzling(e.Sel.Name, types[0]) {
cs.addError(e.Pos(), fmt.Sprintf("unexpected swizzling: %s", e.Sel.Name))
return nil, nil, nil, false
}
var t shaderir.Type
switch types[0].Main {
case shaderir.Vec2, shaderir.Vec3, shaderir.Vec4:
switch len(e.Sel.Name) {
case 1:
t.Main = shaderir.Float
case 2:
t.Main = shaderir.Vec2
case 3:
t.Main = shaderir.Vec3
case 4:
t.Main = shaderir.Vec4
}
case shaderir.IVec2, shaderir.IVec3, shaderir.IVec4:
switch len(e.Sel.Name) {
case 1:
t.Main = shaderir.Int
case 2:
t.Main = shaderir.IVec2
case 3:
t.Main = shaderir.IVec3
case 4:
t.Main = shaderir.IVec4
}
}
if t.Equal(&shaderir.Type{}) {
cs.addError(e.Pos(), fmt.Sprintf("unexpected swizzling: %s", e.Sel.Name))
return nil, nil, nil, false
}
return []shaderir.Expr{
{
Type: shaderir.FieldSelector,
Exprs: []shaderir.Expr{
exprs[0],
{
Type: shaderir.SwizzlingExpr,
Swizzling: e.Sel.Name,
},
},
},
}, []shaderir.Type{t}, stmts, true
case *ast.UnaryExpr:
exprs, ts, stmts, ok := cs.parseExpr(block, fname, e.X, markLocalVariableUsed)
if !ok {
return nil, nil, nil, false
}
if len(exprs) != 1 {
cs.addError(e.Pos(), fmt.Sprintf("multiple-value context is not available at a unary operator: %s", e.X))
return nil, nil, nil, false
}
if exprs[0].Const != nil {
v := gconstant.UnaryOp(e.Op, exprs[0].Const, 0)
// Use the original type as it is.
// Keep the type untyped if the original expression is untyped (#2705).
return []shaderir.Expr{
{
Type: shaderir.NumberExpr,
Const: v,
},
}, ts[:1], stmts, true
}
var op shaderir.Op
switch e.Op {
case token.ADD:
op = shaderir.Add
case token.SUB:
op = shaderir.Sub
case token.NOT:
op = shaderir.NotOp
default:
cs.addError(e.Pos(), fmt.Sprintf("unexpected operator: %s", e.Op))
return nil, nil, nil, false
}
return []shaderir.Expr{
{
Type: shaderir.Unary,
Op: op,
Exprs: exprs,
},
}, ts[:1], stmts, true
case *ast.CompositeLit:
t, ok := cs.parseType(block, fname, e.Type)
if !ok {
return nil, nil, nil, false
}
if t.Main != shaderir.Array {
cs.addError(e.Pos(), fmt.Sprintf("invalid composite literal type %s", t.String()))
return nil, nil, nil, false
}
if t.Main == shaderir.Array && t.Length == -1 {
t.Length = len(e.Elts)
}
idx := block.totalLocalVariableCount()
block.vars = append(block.vars, variable{
typ: t,
})
var stmts []shaderir.Stmt
for i, e := range e.Elts {
exprs, _, ss, ok := cs.parseExpr(block, fname, e, markLocalVariableUsed)
if !ok {
return nil, nil, nil, false
}
if len(exprs) != 1 {
cs.addError(e.Pos(), "multiple-value context is not available at a composite literal")
return nil, nil, nil, false
}
expr := exprs[0]
if expr.Const != nil {
switch t.Sub[0].Main {
case shaderir.Bool:
if expr.Const.Kind() != gconstant.Bool {
cs.addError(e.Pos(), fmt.Sprintf("cannot %s to type bool", expr.Const.String()))
}
case shaderir.Int:
if !canTruncateToInteger(expr.Const) {
cs.addError(e.Pos(), fmt.Sprintf("constant %s truncated to integer", expr.Const.String()))
return nil, nil, nil, false
}
expr.Const = gconstant.ToInt(expr.Const)
case shaderir.Float:
if !canTruncateToFloat(expr.Const) {
cs.addError(e.Pos(), fmt.Sprintf("constant %s truncated to float", expr.Const.String()))
return nil, nil, nil, false
}
expr.Const = gconstant.ToFloat(expr.Const)
default:
cs.addError(e.Pos(), fmt.Sprintf("constant %s cannot be used for the array type %s", expr.Const.String(), t.String()))
return nil, nil, nil, false
}
}
stmts = append(stmts, ss...)
stmts = append(stmts, shaderir.Stmt{
Type: shaderir.Assign,
Exprs: []shaderir.Expr{
{
Type: shaderir.Index,
Exprs: []shaderir.Expr{
{
Type: shaderir.LocalVariable,
Index: idx,
},
{
Type: shaderir.NumberExpr,
Const: gconstant.MakeInt64(int64(i)),
},
},
},
expr,
},
})
}
return []shaderir.Expr{
{
Type: shaderir.LocalVariable,
Index: idx,
},
}, []shaderir.Type{t}, stmts, true
case *ast.IndexExpr:
var stmts []shaderir.Stmt
// Parse the index first
exprs, _, ss, ok := cs.parseExpr(block, fname, e.Index, true)
if !ok {
return nil, nil, nil, false
}
stmts = append(stmts, ss...)
if len(exprs) != 1 {
cs.addError(e.Pos(), "multiple-value context is not available at an index expression")
return nil, nil, nil, false
}
idx := exprs[0]
if idx.Const != nil {
if !canTruncateToInteger(idx.Const) {
cs.addError(e.Pos(), fmt.Sprintf("constant %s truncated to integer", idx.Const.String()))
return nil, nil, nil, false
}
}
exprs, ts, ss, ok := cs.parseExpr(block, fname, e.X, markLocalVariableUsed)
if !ok {
return nil, nil, nil, false
}
stmts = append(stmts, ss...)
if len(exprs) != 1 {
cs.addError(e.Pos(), "multiple-value context is not available at an index expression")
return nil, nil, nil, false
}
x := exprs[0]
t := ts[0]
var typ shaderir.Type
switch t.Main {
case shaderir.Vec2, shaderir.Vec3, shaderir.Vec4:
typ = shaderir.Type{Main: shaderir.Float}
case shaderir.IVec2, shaderir.IVec3, shaderir.IVec4:
typ = shaderir.Type{Main: shaderir.Int}
case shaderir.Mat2:
typ = shaderir.Type{Main: shaderir.Vec2}
case shaderir.Mat3:
typ = shaderir.Type{Main: shaderir.Vec3}
case shaderir.Mat4:
typ = shaderir.Type{Main: shaderir.Vec4}
case shaderir.Array:
typ = t.Sub[0]
default:
cs.addError(e.Pos(), fmt.Sprintf("index operator cannot be applied to the type %s", t.String()))
return nil, nil, nil, false
}
return []shaderir.Expr{
{
Type: shaderir.Index,
Exprs: []shaderir.Expr{
x,
idx,
},
},
}, []shaderir.Type{typ}, stmts, true
default:
cs.addError(e.Pos(), fmt.Sprintf("expression not implemented: %#v", e))
}
return nil, nil, nil, false
}
func isValidSwizzling(swizzling string, t shaderir.Type) bool {
if !shaderir.IsValidSwizzling(swizzling) {
return false
}
switch t.Main {
case shaderir.Vec2, shaderir.IVec2:
return !strings.ContainsAny(swizzling, "zwbapq")
case shaderir.Vec3, shaderir.IVec3:
return !strings.ContainsAny(swizzling, "waq")
case shaderir.Vec4, shaderir.IVec4:
return true
default:
return false
}
}
func resolveConstKind(exprs []shaderir.Expr, ts []shaderir.Type) (kind gconstant.Kind, allConsts bool) {
if len(exprs) != len(ts) {
panic("not reached")
}
for _, expr := range exprs {
if expr.Const == nil {
return gconstant.Unknown, false
}
}
kind = gconstant.Unknown
for _, t := range ts {
switch t.Main {
case shaderir.None:
continue
case shaderir.Int:
switch kind {
case gconstant.Unknown:
kind = gconstant.Int
case gconstant.Int:
case gconstant.Float:
return gconstant.Unknown, true
}
case shaderir.Float:
switch kind {
case gconstant.Unknown:
kind = gconstant.Float
case gconstant.Int:
return gconstant.Unknown, true
case gconstant.Float:
}
}
}
// Prefer floats over integers for non-typed constant values.
// For example, max(1.0, 1) should return a float value.
if kind == gconstant.Unknown {
for _, expr := range exprs {
if expr.Const.Kind() == gconstant.Float {
return gconstant.Float, true
}
}
}
return gconstant.Int, true
}