simplify type deduction in TypeFromBinaryOp for shift op

This reverts commit 7f9d997175.

internal/shader/delayed.go

@@ -1,165 +0,0 @@
-// Copyright 2024 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"
-	gconstant "go/constant"
-
-	"github.com/hajimehoshi/ebiten/v2/internal/shaderir"
-)
-
-type delayedTypeValidator interface {
-	Validate(t shaderir.Type) (shaderir.Type, bool)
-	IsValidated() (shaderir.Type, bool)
-	Error() string
-}
-
-func isArgDefaultTypeInt(f shaderir.BuiltinFunc) bool {
-	return f == shaderir.IntF || f == shaderir.IVec2F || f == shaderir.IVec3F || f == shaderir.IVec4F
-}
-
-func isIntType(t shaderir.Type) bool {
-	return t.Main == shaderir.Int || t.IsIntVector()
-}
-
-func (cs *compileState) ValidateDefaultTypesForExpr(block *block, expr shaderir.Expr, t shaderir.Type) shaderir.Type {
-	if check, ok := cs.delayedTypeCheks[expr.Ast]; ok {
-		if resT, ok := check.IsValidated(); ok {
-			return resT
-		}
-		resT, ok := check.Validate(t)
-		if !ok {
-			return shaderir.Type{Main: shaderir.None}
-		}
-		return resT
-	}
-
-	switch expr.Type {
-	case shaderir.LocalVariable:
-		return block.vars[expr.Index].typ
-
-	case shaderir.Binary:
-		left := expr.Exprs[0]
-		right := expr.Exprs[1]
-
-		leftType := cs.ValidateDefaultTypesForExpr(block, left, t)
-		rightType := cs.ValidateDefaultTypesForExpr(block, right, t)
-
-		// Usure about top-level type, try to validate by neighbour type
-		// The same work is done twice. Can it be optimized?
-		if t.Main == shaderir.None {
-			cs.ValidateDefaultTypesForExpr(block, left, rightType)
-			cs.ValidateDefaultTypesForExpr(block, right, leftType)
-		}
-	case shaderir.Call:
-		fun := expr.Exprs[0]
-		if fun.Type == shaderir.BuiltinFuncExpr {
-			if isArgDefaultTypeInt(fun.BuiltinFunc) {
-				for _, e := range expr.Exprs[1:] {
-					cs.ValidateDefaultTypesForExpr(block, e, shaderir.Type{Main: shaderir.Int})
-				}
-				return shaderir.Type{Main: shaderir.Int}
-			}
-
-			for _, e := range expr.Exprs[1:] {
-				cs.ValidateDefaultTypesForExpr(block, e, shaderir.Type{Main: shaderir.Float})
-			}
-			return shaderir.Type{Main: shaderir.Float}
-		}
-
-		if fun.Type == shaderir.FunctionExpr {
-			args := cs.funcs[fun.Index].ir.InParams
-
-			for i, e := range expr.Exprs[1:] {
-				cs.ValidateDefaultTypesForExpr(block, e, args[i])
-			}
-
-			retT := cs.funcs[fun.Index].ir.Return
-
-			return retT
-		}
-	}
-
-	return shaderir.Type{Main: shaderir.None}
-}
-
-func (cs *compileState) ValidateDefaultTypes(block *block, stmt shaderir.Stmt) {
-	switch stmt.Type {
-	case shaderir.Assign:
-		left := stmt.Exprs[0]
-		right := stmt.Exprs[1]
-		if left.Type == shaderir.LocalVariable {
-			varType := block.vars[left.Index].typ
-			// Type is not explicitly specified
-			if stmt.IsTypeGuessed {
-				varType = shaderir.Type{Main: shaderir.None}
-			}
-			cs.ValidateDefaultTypesForExpr(block, right, varType)
-		}
-	case shaderir.ExprStmt:
-		for _, e := range stmt.Exprs {
-			cs.ValidateDefaultTypesForExpr(block, e, shaderir.Type{Main: shaderir.None})
-		}
-	}
-}
-
-type delayedShiftValidator struct {
-	shiftType      shaderir.Op
-	value          gconstant.Value
-	validated      bool
-	closestUnknown bool
-	failed         bool
-}
-
-func (d *delayedShiftValidator) IsValidated() (shaderir.Type, bool) {
-	if d.failed {
-		return shaderir.Type{}, false
-	}
-	if d.validated {
-		return shaderir.Type{Main: shaderir.Int}, true
-	}
-	// If only matched with None
-	if d.closestUnknown {
-		// Was it originally represented by an int constant?
-		if d.value.Kind() == gconstant.Int {
-			return shaderir.Type{Main: shaderir.Int}, true
-		}
-	}
-	return shaderir.Type{}, false
-}
-
-func (d *delayedShiftValidator) Validate(t shaderir.Type) (shaderir.Type, bool) {
-	if d.validated {
-		return shaderir.Type{Main: shaderir.Int}, true
-	}
-	if isIntType(t) {
-		d.validated = true
-		return shaderir.Type{Main: shaderir.Int}, true
-	}
-	if t.Main == shaderir.None {
-		d.closestUnknown = true
-		return t, true
-	}
-	return shaderir.Type{Main: shaderir.None}, false
-}
-
-func (d *delayedShiftValidator) Error() string {
-	st := "left shift"
-	if d.shiftType == shaderir.RightShift {
-		st = "right shift"
-	}
-	return fmt.Sprintf("left operand for %s should be int", st)
-}

internal/shader/expr.go

@@ -36,7 +36,7 @@ func canTruncateToFloat(v gconstant.Value) bool {
 
 var textureVariableRe = regexp.MustCompile(`\A__t(\d+)\z`)
 
-func (cs *compileState) parseExpr(block *block, fname string, expr ast.Expr, markLocalVariableUsed bool) (rexpr []shaderir.Expr, rtype []shaderir.Type, rstmt []shaderir.Stmt, ok bool) {
+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 {
@@ -101,14 +101,7 @@ func (cs *compileState) parseExpr(block *block, fname string, expr ast.Expr, mar
 		}
 
 		// Resolve untyped constants.
-		var l gconstant.Value
-		var r gconstant.Value
-		origLvalue := lhs[0].Const
-		if op2 == shaderir.LeftShift || op2 == shaderir.RightShift {
-			l, r, ok = shaderir.ResolveUntypedConstsForBitShiftOp(lhs[0].Const, rhs[0].Const, lhst, rhst)
-		} else {
-			l, r, ok = shaderir.ResolveUntypedConstsForBinaryOp(lhs[0].Const, rhs[0].Const, lhst, rhst)
-		}
+		l, r, ok := shaderir.ResolveUntypedConstsForBinaryOp(op2, 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()))
@@ -116,27 +109,6 @@ func (cs *compileState) parseExpr(block *block, fname string, expr ast.Expr, mar
 		}
 		lhs[0].Const, rhs[0].Const = l, r
 
-		if op2 == shaderir.LeftShift || op2 == shaderir.RightShift {
-			if !(lhst.Main == shaderir.None && rhst.Main == shaderir.None) {
-				// If both are const
-				if rhs[0].Const != nil && (rhst.Main == shaderir.None || lhs[0].Const != nil) {
-					rhst = shaderir.Type{Main: shaderir.Int}
-				}
-
-				// If left is untyped const
-				if lhst.Main == shaderir.None && lhs[0].Const != nil {
-					lhst = shaderir.Type{Main: shaderir.Int}
-					// Left should be implicitly converted to the type it would assume if the shift expression were replaced by its left operand alone.
-					if rhs[0].Const == nil {
-						defer func() {
-							if ok {
-								cs.addDelayedTypeCheck(expr, &delayedShiftValidator{value: origLvalue})
-							}
-						}()
-					}
-				}
-			}
-		} else {
 		// If either is typed, resolve the other type.
 		// If both are untyped, keep them untyped.
 		if lhst.Main != shaderir.None || rhst.Main != shaderir.None {
@@ -161,7 +133,6 @@ func (cs *compileState) parseExpr(block *block, fname string, expr ast.Expr, mar
 				}
 			}
 		}
-		}
 
 		t, ok := shaderir.TypeFromBinaryOp(op2, lhst, rhst, lhs[0].Const, rhs[0].Const)
 		if !ok {
@@ -201,7 +172,6 @@ func (cs *compileState) parseExpr(block *block, fname string, expr ast.Expr, mar
 			{
 				Type:  shaderir.Binary,
 				Op:    op2,
-				Ast:   expr,
 				Exprs: []shaderir.Expr{lhs[0], rhs[0]},
 			},
 		}, []shaderir.Type{t}, stmts, true

internal/shader/shader.go

@@ -61,8 +61,6 @@ type compileState struct {
 
 	varyingParsed bool
 
-	delayedTypeCheks map[ast.Expr]delayedTypeValidator
-
 	errs []string
 }
 
@@ -84,13 +82,6 @@ func (cs *compileState) findUniformVariable(name string) (int, bool) {
 	return 0, false
 }
 
-func (cs *compileState) addDelayedTypeCheck(at ast.Expr, check delayedTypeValidator) {
-	if cs.delayedTypeCheks == nil {
-		cs.delayedTypeCheks = make(map[ast.Expr]delayedTypeValidator, 1)
-	}
-	cs.delayedTypeCheks[at] = check
-}
-
 type typ struct {
 	name string
 	ir   shaderir.Type

internal/shader/stmt.go

@@ -49,10 +49,6 @@ func (cs *compileState) parseStmt(block *block, fname string, stmt ast.Stmt, inP
 			if !ok {
 				return nil, false
 			}
-			for i := range ss {
-				ss[i].IsTypeGuessed = true
-			}
-
 			stmts = append(stmts, ss...)
 		case token.ASSIGN:
 			if len(stmt.Lhs) != len(stmt.Rhs) && len(stmt.Rhs) != 1 {
@@ -477,25 +473,6 @@ func (cs *compileState) parseStmt(block *block, fname string, stmt ast.Stmt, inP
 		cs.addError(stmt.Pos(), fmt.Sprintf("unexpected statement: %#v", stmt))
 		return nil, false
 	}
-
-	// Need to run delayed checks
-	if len(cs.delayedTypeCheks) != 0 {
-		for _, st := range stmts {
-			cs.ValidateDefaultTypes(block, st)
-		}
-
-		// Collect all errors first
-		foundErr := false
-		for s, v := range cs.delayedTypeCheks {
-			if _, ok := v.IsValidated(); !ok {
-				foundErr = true
-				cs.addError(s.Pos(), v.Error())
-			}
-		}
-		if foundErr {
-			return nil, false
-		}
-	}
 	return stmts, true
 }
 

internal/shader/syntax_test.go

@@ -1320,62 +1320,14 @@ func TestSyntaxOperatorShift(t *testing.T) {
 		stmt string
 		err  bool
 	}{
-		{stmt: "b := 2.0; a := 1.0 << 2.0 == b; _ = a", err: false},
-		{stmt: "s := 1; b := 2.0; a := 1.0<<s == b; _ = a", err: true},
-		{stmt: "s := 1; b := 2; a := 1.0<<s == b; _ = a", err: false},
-		{stmt: "s := 1; a := 2.0<<s + ivec2(3.0<<s); _ = a", err: false},
-		{stmt: "s := 1; a := 2.0<<s + vec2(3); _ = a", err: true},
-		{stmt: "s := 1; a := 2.0<<s + ivec2(3); _ = a", err: false},
-		{stmt: "s := 1; a := 2.0<<s + foo_int_int(3.0<<s); _ = a", err: false},
-		{stmt: "s := 1; a := 2.0<<s + 3.0<<s; _ = a", err: true},
-		{stmt: "s := 1; a := 2<<s + 3.0<<s; _ = a", err: true},
-		{stmt: "s := 1; a := 2.0<<s + 3<<s; _ = a", err: true},
-		{stmt: "s := 1; a := 2<<s + 3<<s; _ = a", err: false},
-		{stmt: "s := 1; foo_multivar(0, 0, 2<<s)", err: false},
-		{stmt: "s := 1; foo_multivar(0, 2.0<<s, 0)", err: true},
-		{stmt: "s := 1; foo_multivar(2.0<<s, 0, 0)", err: false},
-		{stmt: "s := 1; a := foo_multivar(2.0<<s, 0, 0); _ = a", err: false},
-		{stmt: "s := 1; a := foo_multivar(0, 2.0<<s, 0); _ = a", err: true},
-		{stmt: "s := 1; a := foo_multivar(0, 0, 2.0<<s); _ = a", err: false},
-		{stmt: "a := foo_multivar(0, 0, 1.0<<2.0); _ = a", err: false},
-		{stmt: "a := foo_multivar(0, 1.0<<2.0, 0); _ = a", err: false},
-		{stmt: "s := 1; a := int(1) + 1.0<<s + int(float(1<<s)); _ = a", err: true},
-		{stmt: "s := 1; var a int = 1.0 << 2.0 << 3.0 << 4.0 << s; _ = a", err: false},
-		{stmt: "s := 1; var a float = 1 << 1 << 1 << 1 << s; _ = a", err: true},
-		{stmt: "s := 1; var a float = 1 << s + 1.2; _ = a", err: true},
-		{stmt: "s := 1; a := 1.0 << s + 1.2; _ = a", err: true},
-		{stmt: "s := 1; a := 1.0 << s + foo_float_float(2); _ = a", err: true},
-		{stmt: "s := 1; a := 1.0 << s + foo_float_int(2); _ = a", err: false},
-		{stmt: "s := 1; a := foo_float_int(1.0<<s) + foo_float_int(2); _ = a", err: true},
-		{stmt: "s := 1; a := foo_int_float(1<<s) + foo_int_float(2); _ = a", err: false},
-		{stmt: "s := 1; a := foo_int_int(1<<s) + foo_int_int(2); _ = a", err: false},
-		{stmt: "s := 1; t := 2.0; a := t + 1.0 << s; _ = a", err: true},
-		{stmt: "s := 1; t := 2; a := t + 1.0 << s; _ = a", err: false},
-		{stmt: "s := 1; b := 1 << s; _ = b", err: false},
-		{stmt: "var a = 1; b := a << 2.0; _ = b", err: false},
-		{stmt: "s := 1; var a float; a = 1 << s; _ = a", err: true},
-		{stmt: "s := 1; var a float = 1 << s; _ = a", err: true},
-		{stmt: "s := 1; var a float = float(1.0 << s); _ = a", err: true},
-		{stmt: "s := 1; var a int = int(1 << s); _ = a", err: false},
-		{stmt: "s := 1; var a int = int(1.0 << s); _ = a", err: false},
-		{stmt: "s := 1; a := 1 << s; _ = a", err: false},
-		{stmt: "s := 1; a := 1.0 << s; _ = a", err: true},
-		{stmt: "s := 1; a := int(1.0 << s); _ = a", err: false},
-		{stmt: "s := 1; var a float = float(1.0 << s); _ = a", err: true},
-		{stmt: "s := 1; var a float = 1.0 << s; _ = a", err: true},
-		{stmt: "s := 1; var a float = 1 << s; _ = a", err: true},
-		{stmt: "s := 1; var a int = 1.0 << s; _ = a", err: false},
-		{stmt: "s := 1; var a int = 1 << s; _ = a", err: false},
-		{stmt: "var a float = 1.0 << 2.0; _ = a", err: false},
-		{stmt: "var a int = 1.0 << 2; _ = a", err: false},
-		{stmt: "var a float = 1.0 << 2; _ = a", err: false},
+		{stmt: "a := 1 << 2; _ = a", err: false},
 		{stmt: "a := 1 << 2.0; _ = a", err: false},
 		{stmt: "a := 1.0 << 2; _ = a", err: false},
 		{stmt: "a := 1.0 << 2.0; _ = a", err: false},
-		{stmt: "a := 1 << 2; _ = a", err: false},
+		{stmt: "var a = 1; b := a << 2.0; _ = b", err: false},
+		{stmt: "var a = 1; b := 2.0 << a; _ = b", err: false}, // PR: #2916
 		{stmt: "a := float(1.0) << 2; _ = a", err: true},
-		{stmt: "a := 1 << float(2.0); _ = a", err: false},
-		{stmt: "a := 1.0 << float(2.0); _ = a", err: false},
+		{stmt: "a := 1 << float(2.0); _ = a", err: true},
 		{stmt: "a := ivec2(1) << 2; _ = a", err: false},
 		{stmt: "a := 1 << ivec2(2); _ = a", err: true},
 		{stmt: "a := ivec2(1) << float(2.0); _ = a", err: true},
@@ -1395,62 +1347,14 @@ func TestSyntaxOperatorShift(t *testing.T) {
 		{stmt: "a := vec3(1) << ivec2(2); _ = a", err: true},
 		{stmt: "a := ivec2(1) << vec3(2); _ = a", err: true},
 
-		{stmt: "b := 2.0; a := 1.0 >> 2.0 == b; _ = a", err: false},
-		{stmt: "s := 1; b := 2.0; a := 1.0>>s == b; _ = a", err: true},
-		{stmt: "s := 1; b := 2; a := 1.0>>s == b; _ = a", err: false},
-		{stmt: "s := 1; a := 2.0>>s + ivec2(3.0>>s); _ = a", err: false},
-		{stmt: "s := 1; a := 2.0>>s + vec2(3); _ = a", err: true},
-		{stmt: "s := 1; a := 2.0>>s + ivec2(3); _ = a", err: false},
-		{stmt: "s := 1; a := 2.0>>s + foo_int_int(3.0>>s); _ = a", err: false},
-		{stmt: "s := 1; a := 2.0>>s + 3.0>>s; _ = a", err: true},
-		{stmt: "s := 1; a := 2>>s + 3.0>>s; _ = a", err: true},
-		{stmt: "s := 1; a := 2.0>>s + 3>>s; _ = a", err: true},
-		{stmt: "s := 1; a := 2>>s + 3>>s; _ = a", err: false},
-		{stmt: "s := 1; foo_multivar(0, 0, 2>>s)", err: false},
-		{stmt: "s := 1; foo_multivar(0, 2.0>>s, 0)", err: true},
-		{stmt: "s := 1; foo_multivar(2.0>>s, 0, 0)", err: false},
-		{stmt: "s := 1; a := foo_multivar(2.0>>s, 0, 0); _ = a", err: false},
-		{stmt: "s := 1; a := foo_multivar(0, 2.0>>s, 0); _ = a", err: true},
-		{stmt: "s := 1; a := foo_multivar(0, 0, 2.0>>s); _ = a", err: false},
-		{stmt: "a := foo_multivar(0, 0, 1.0>>2.0); _ = a", err: false},
-		{stmt: "a := foo_multivar(0, 1.0>>2.0, 0); _ = a", err: false},
-		{stmt: "s := 1; a := int(1) + 1.0>>s + int(float(1>>s)); _ = a", err: true},
-		{stmt: "s := 1; var a int = 1.0 >> 2.0 >> 3.0 >> 4.0 >> s; _ = a", err: false},
-		{stmt: "s := 1; var a float = 1 >> 1 >> 1 >> 1 >> s; _ = a", err: true},
-		{stmt: "s := 1; var a float = 1 >> s + 1.2; _ = a", err: true},
-		{stmt: "s := 1; a := 1.0 >> s + 1.2; _ = a", err: true},
-		{stmt: "s := 1; a := 1.0 >> s + foo_float_float(2); _ = a", err: true},
-		{stmt: "s := 1; a := 1.0 >> s + foo_float_int(2); _ = a", err: false},
-		{stmt: "s := 1; a := foo_float_int(1.0>>s) + foo_float_int(2); _ = a", err: true},
-		{stmt: "s := 1; a := foo_int_float(1>>s) + foo_int_float(2); _ = a", err: false},
-		{stmt: "s := 1; a := foo_int_int(1>>s) + foo_int_int(2); _ = a", err: false},
-		{stmt: "s := 1; t := 2.0; a := t + 1.0 >> s; _ = a", err: true},
-		{stmt: "s := 1; t := 2; a := t + 1.0 >> s; _ = a", err: false},
-		{stmt: "s := 1; b := 1 >> s; _ = b", err: false},
-		{stmt: "var a = 1; b := a >> 2.0; _ = b", err: false},
-		{stmt: "s := 1; var a float; a = 1 >> s; _ = a", err: true},
-		{stmt: "s := 1; var a float = 1 >> s; _ = a", err: true},
-		{stmt: "s := 1; var a float = float(1.0 >> s); _ = a", err: true},
-		{stmt: "s := 1; var a int = int(1 >> s); _ = a", err: false},
-		{stmt: "s := 1; var a int = int(1.0 >> s); _ = a", err: false},
-		{stmt: "s := 1; a := 1 >> s; _ = a", err: false},
-		{stmt: "s := 1; a := 1.0 >> s; _ = a", err: true},
-		{stmt: "s := 1; a := int(1.0 >> s); _ = a", err: false},
-		{stmt: "s := 1; var a float = float(1.0 >> s); _ = a", err: true},
-		{stmt: "s := 1; var a float = 1.0 >> s; _ = a", err: true},
-		{stmt: "s := 1; var a float = 1 >> s; _ = a", err: true},
-		{stmt: "s := 1; var a int = 1.0 >> s; _ = a", err: false},
-		{stmt: "s := 1; var a int = 1 >> s; _ = a", err: false},
-		{stmt: "var a float = 1.0 >> 2.0; _ = a", err: false},
-		{stmt: "var a int = 1.0 >> 2; _ = a", err: false},
-		{stmt: "var a float = 1.0 >> 2; _ = a", err: false},
+		{stmt: "a := 1 >> 2; _ = a", err: false},
 		{stmt: "a := 1 >> 2.0; _ = a", err: false},
 		{stmt: "a := 1.0 >> 2; _ = a", err: false},
 		{stmt: "a := 1.0 >> 2.0; _ = a", err: false},
-		{stmt: "a := 1 >> 2; _ = a", err: false},
+		{stmt: "var a = 1; b := a >> 2.0; _ = b", err: false},
+		{stmt: "var a = 1; b := 2.0 >> a; _ = b", err: false}, // PR: #2916
 		{stmt: "a := float(1.0) >> 2; _ = a", err: true},
-		{stmt: "a := 1 >> float(2.0); _ = a", err: false},
-		{stmt: "a := 1.0 >> float(2.0); _ = a", err: false},
+		{stmt: "a := 1 >> float(2.0); _ = a", err: true},
 		{stmt: "a := ivec2(1) >> 2; _ = a", err: false},
 		{stmt: "a := 1 >> ivec2(2); _ = a", err: true},
 		{stmt: "a := ivec2(1) >> float(2.0); _ = a", err: true},
@@ -1473,11 +1377,7 @@ func TestSyntaxOperatorShift(t *testing.T) {
 
 	for _, c := range cases {
 		_, err := compileToIR([]byte(fmt.Sprintf(`package main
-func foo_multivar(x int, y float, z int) int {return x}
-func foo_int_int(x int) int {return x}
-func foo_float_int(x float) int {return int(x)}
-func foo_int_float(x int) float {return float(x)}
-func foo_float_float(x float) float {return x}
+
 func Fragment(dstPos vec4, srcPos vec2, color vec4) vec4 {
 	%s
 	return dstPos

internal/shaderir/check.go

@@ -18,31 +18,21 @@ import (
 	"go/constant"
 )
 
-func ResolveUntypedConstsForBitShiftOp(lhs, rhs constant.Value, lhst, rhst Type) (newLhs, newRhs constant.Value, ok bool) {
-	cLhs := lhs
-	cRhs := rhs
-
-	// Right is const -> int
-	if rhs != nil {
-		cRhs = constant.ToInt(rhs)
-		if cRhs.Kind() == constant.Unknown {
-			return nil, nil, false
-		}
-	}
-
-	// Left if untyped const -> int
-	if lhs != nil && lhst.Main == None {
-		cLhs = constant.ToInt(lhs)
-		if cLhs.Kind() == constant.Unknown {
-			return nil, nil, false
-		}
-	}
-
-	return cLhs, cRhs, true
-}
-
-func ResolveUntypedConstsForBinaryOp(lhs, rhs constant.Value, lhst, rhst Type) (newLhs, newRhs constant.Value, ok bool) {
+func ResolveUntypedConstsForBinaryOp(op Op, lhs, rhs constant.Value, lhst, rhst Type) (newLhs, newRhs constant.Value, ok bool) {
 	if lhst.Main == None && rhst.Main == None {
+		if op == LeftShift || op == RightShift {
+			newLhs = constant.ToInt(lhs)
+			newRhs = constant.ToInt(rhs)
+
+			if newLhs.Kind() == constant.Unknown {
+				return nil, nil, false
+			}
+			if newRhs.Kind() == constant.Unknown {
+				return nil, nil, false
+			}
+			return newLhs, newRhs, true
+		}
+
 		if lhs.Kind() == rhs.Kind() {
 			return lhs, rhs, true
 		}
@@ -121,6 +111,13 @@ func TypeFromBinaryOp(op Op, lhst, rhst Type, lhsConst, rhsConst constant.Value)
 			return Type{}, false
 		}
 
+		if op == LeftShift || op == RightShift {
+			if lhsConst.Kind() == constant.Int && rhsConst.Kind() == constant.Int {
+				return Type{Main: Int}, true
+			}
+			return Type{}, false
+		}
+
 		if op == EqualOp || op == NotEqualOp || op == LessThanOp || op == LessThanEqualOp || op == GreaterThanOp || op == GreaterThanEqualOp {
 			return Type{Main: Bool}, true
 		}
@@ -144,16 +141,6 @@ func TypeFromBinaryOp(op Op, lhst, rhst Type, lhsConst, rhsConst constant.Value)
 		panic("shaderir: cannot resolve untyped values")
 	}
 
-	if op == LeftShift || op == RightShift {
-		if (lhst.Main == Int || lhst.IsIntVector()) && rhst.Main == Int {
-			return lhst, true
-		}
-		if lhst.IsIntVector() && rhst.IsIntVector() && lhst.VectorElementCount() == rhst.VectorElementCount() {
-			return lhst, true
-		}
-		return Type{}, false
-	}
-
 	if op == AndAnd || op == OrOr {
 		if lhst.Main == Bool && rhst.Main == Bool {
 			return Type{Main: Bool}, true
@@ -228,6 +215,16 @@ func TypeFromBinaryOp(op Op, lhst, rhst Type, lhsConst, rhsConst constant.Value)
 		return Type{}, false
 	}
 
+	if op == LeftShift || op == RightShift {
+		if (lhst.Main == Int || lhst.IsIntVector()) && rhst.Main == Int {
+			return lhst, true
+		}
+		if lhst.IsIntVector() && rhst.IsIntVector() && lhst.VectorElementCount() == rhst.VectorElementCount() {
+			return lhst, true
+		}
+		return Type{}, false
+	}
+
 	if lhst.Equal(&rhst) {
 		if lhst.Main == None {
 			return rhst, true

internal/shaderir/program.go

@@ -16,7 +16,6 @@
 package shaderir
 
 import (
-	"go/ast"
 	"go/constant"
 	"go/token"
 	"sort"
@@ -85,7 +84,6 @@ type Stmt struct {
 	ForOp       Op
 	ForDelta    constant.Value
 	InitIndex   int
-	IsTypeGuessed bool
 }
 
 type StmtType int
@@ -111,7 +109,6 @@ type Expr struct {
 	Swizzling   string
 	Index       int
 	Op          Op
-	Ast         ast.Expr
 }
 
 type ExprType int