mirror of
https://github.com/golang/go
synced 2024-11-22 00:34:40 -07:00
Implement multi-valued functions, multi-valued return, and
unpacking for assignments, call arguments, and returns. This change revamps the whole assignment compilation system to be multi-valued, using the new MultiType type and multiV value. Function calls, returns, and assignments now share a lot of code and produce very consistent error messages. R=rsc APPROVED=rsc DELTA=510 (335 added, 74 deleted, 101 changed) OCL=32248 CL=32258
This commit is contained in:
Austin Clements
parent
eece85c9a7
commit
75760a4b5d
@ -35,6 +35,9 @@ type FuncDecl struct
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func (a *compiler) compileFunc(scope *Scope, decl *FuncDecl, body *ast.BlockStmt) (func (f *Frame) Func)
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type exprCompiler struct
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func (a *compiler) compileExpr(scope *Scope, expr ast.Expr, constant bool) *exprCompiler
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type assignCompiler struct
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func (a *compiler) checkAssign(pos token.Position, rs []*exprCompiler, errOp, errPosName string) (*assignCompiler, bool)
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func (a *compiler) compileAssign(pos token.Position, lt Type, rs []*exprCompiler, errOp, errPosName string) (func(lv Value, f *Frame))
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func (a *compiler) compileType(scope *Scope, typ ast.Expr) Type
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func (a *compiler) compileFuncType(scope *Scope, typ *ast.FuncType) *FuncDecl
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@ -42,11 +45,12 @@ func (a *compiler) compileArrayLen(scope *Scope, expr ast.Expr) (int64, bool)
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type codeBuf struct
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type FuncType struct
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// A funcCompiler captures information used throughout the compilation
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// of a single function body.
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type funcCompiler struct {
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*compiler;
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outVars []*Variable;
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fnType *FuncType;
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// Whether the out variables are named. This affects what
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// kinds of return statements are legal.
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outVarsNamed bool;
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@ -37,6 +37,7 @@ type exprCompiler struct {
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evalArray func(f *Frame) ArrayValue;
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evalPtr func(f *Frame) Value;
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evalFunc func(f *Frame) Func;
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evalMulti func(f *Frame) []Value;
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// Evaluate to the "address of" this value; that is, the
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// settable Value object. nil for expressions whose address
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// cannot be taken.
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@ -179,6 +180,13 @@ func (a *exprCompiler) asFunc() (func(f *Frame) Func) {
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return a.evalFunc;
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}
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func (a *exprCompiler) asMulti() (func(f *Frame) []Value) {
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if a.evalMulti == nil {
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log.Crashf("tried to get %v node as MultiType", a.t);
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}
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return a.evalMulti;
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}
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/*
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* Common expression manipulations
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*/
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@ -186,6 +194,8 @@ func (a *exprCompiler) asFunc() (func(f *Frame) Func) {
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// a.convertTo(t) converts the value of the analyzed expression a,
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// which must be a constant, ideal number, to a new analyzed
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// expression with a constant value of type t.
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//
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// TODO(austin) Rename to resolveIdeal or something?
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func (a *exprCompiler) convertTo(t Type) *exprCompiler {
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if !a.t.isIdeal() {
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log.Crashf("attempted to convert from %v, expected ideal", a.t);
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@ -256,66 +266,193 @@ func (a *exprCompiler) convertTo(t Type) *exprCompiler {
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return res;
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}
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// mkAssign takes an optional expected l-value type, lt, and an
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// r-value expression compiler, r, and returns the expected l-value
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// type and a function that evaluates the r-value and assigns it to
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// the l-value lv.
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/*
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* Assignments
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*/
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// An assignCompiler compiles assignment operations. Anything other
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// than short declarations should use the compileAssign wrapper.
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//
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// If lt is non-nil, the returned l-value type will always be lt. If
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// lt is nil, mkAssign will infer and return the appropriate l-value
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// type, or produce an error.
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//
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// errOp specifies the operation name to use for error messages, such
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// as "assignment", or "function call". errPosName specifies the name
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// to use for positions. errPos, if non-zero, specifies the position
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// of this assignment (for tuple assignments or function arguments).
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//
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// If the assignment fails to typecheck, this generates an error
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// message and returns nil, nil.
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func mkAssign(lt Type, r *exprCompiler, errOp string, errPosName string, errPos int) (Type, func(lv Value, f *Frame)) {
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// However, when [an ideal is] (used in an expression)
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// assigned to a variable or typed constant, the destination
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// must be able to represent the assigned value.
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if r.t.isIdeal() && (lt == nil || lt.isInteger() || lt.isFloat()) {
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// If the type is absent and the corresponding
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// expression is a constant expression of ideal
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// integer or ideal float type, the type of the
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// declared variable is int or float respectively.
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if lt == nil {
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switch {
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case r.t.isInteger():
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lt = IntType;
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case r.t.isFloat():
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lt = FloatType;
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default:
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log.Crashf("unexpected ideal type %v", r.t);
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}
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}
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r = r.convertTo(lt);
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if r == nil {
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return nil, nil;
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// There are three valid types of assignment:
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// 1) T = T
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// Assigning a single expression with single-valued type to a
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// single-valued type.
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// 2) MT = T, T, ...
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// Assigning multiple expressions with single-valued types to a
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// multi-valued type.
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// 3) MT = MT
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// Assigning a single expression with multi-valued type to a
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// multi-valued type.
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type assignCompiler struct {
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*compiler;
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pos token.Position;
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// The RHS expressions. This may include nil's for
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// expressions that failed to compile.
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rs []*exprCompiler;
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// The (possibly unary) MultiType of the RHS.
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rmt *MultiType;
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// Whether this is an unpack assignment (case 3).
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isUnpack bool;
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// The operation name to use in error messages, such as
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// "assignment" or "function call".
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errOp string;
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// The name to use for positions in error messages, such as
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// "argument".
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errPosName string;
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}
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// Type check the RHS of an assignment, returning a new assignCompiler
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// and indicating if the type check succeeded. This always returns an
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// assignCompiler with rmt set, but if type checking fails, slots in
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// the MultiType may be nil. If rs contains nil's, type checking will
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// fail and these expressions given a nil type.
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func (a *compiler) checkAssign(pos token.Position, rs []*exprCompiler, errOp, errPosName string) (*assignCompiler, bool) {
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c := &assignCompiler{
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compiler: a,
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pos: pos,
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rs: rs,
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errOp: errOp,
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errPosName: errPosName,
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};
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// Is this an unpack?
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if len(rs) == 1 && rs[0] != nil {
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if rmt, isUnpack := rs[0].t.(*MultiType); isUnpack {
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c.rmt = rmt;
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c.isUnpack = true;
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return c, true;
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}
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}
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// TOOD(austin) Deal with assignment special cases
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if lt == nil {
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lt = r.t;
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} else {
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// Values of any type may always be assigned to
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// variables of compatible static type.
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if lt.literal() != r.t.literal() {
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if errPos == 0 {
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r.diag("illegal operand types for %s\n\t%v\n\t%v", errOp, lt, r.t);
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} else {
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r.diag("illegal operand types in %s %d of %s\n\t%v\n\t%v", errPosName, errPos, errOp, lt, r.t);
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}
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return nil, nil;
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// Create MultiType for RHS and check that all RHS expressions
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// are single-valued.
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rts := make([]Type, len(rs));
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ok := true;
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for i, r := range rs {
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if r == nil {
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ok = false;
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continue;
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}
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if _, isMT := r.t.(*MultiType); isMT {
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r.diag("multi-valued expression not allowed in %s", errOp);
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ok = false;
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continue;
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}
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rts[i] = r.t;
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}
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c.rmt = NewMultiType(rts);
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return c, ok;
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}
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// compile type checks and compiles an assignment operation, returning
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// a function that expects an l-value and the frame in which to
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// evaluate the RHS expressions. The l-value must have exactly the
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// type given by lt. Returns nil if type checking fails.
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func (a *assignCompiler) compile(lt Type) (func(lv Value, f *Frame)) {
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lmt, isMT := lt.(*MultiType);
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rmt, isUnpack := a.rmt, a.isUnpack;
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// Create unary MultiType for single LHS
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if !isMT {
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lmt = NewMultiType([]Type{lt});
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}
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// Check that the assignment count matches
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lcount := len(lmt.Elems);
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rcount := len(rmt.Elems);
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if lcount != rcount {
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msg := "not enough";
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pos := a.pos;
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if rcount > lcount {
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msg = "too many";
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if lcount > 0 {
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pos = a.rs[lcount-1].pos;
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}
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}
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a.diagAt(&pos, "%s %ss for %s\n\t%s\n\t%s", msg, a.errPosName, a.errOp, lt, rmt);
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return nil;
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}
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bad := false;
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// TODO(austin) Deal with assignment special cases. This is
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// tricky in the unpack case, since some of the conversions
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// can apply to single types within the multi-type.
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// Values of any type may always be assigned to variables of
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// compatible static type.
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for i, lt := range lmt.Elems {
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// Check each type individually so we can produce a
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// better error message.
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rt := rmt.Elems[i];
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// When [an ideal is] (used in an expression) assigned
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// to a variable or typed constant, the destination
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// must be able to represent the assigned value.
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if rt.isIdeal() {
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if isUnpack {
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log.Crashf("Right side of unpack contains ideal: %s", rmt);
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}
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a.rs[i] = a.rs[i].convertTo(lmt.Elems[i]);
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if a.rs[i] == nil {
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bad = true;
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continue;
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}
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rt = a.rs[i].t;
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}
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if lt.literal() != rt.literal() {
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if len(a.rs) == 1 {
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a.rs[0].diag("illegal operand types for %s\n\t%v\n\t%v", a.errOp, lt, rt);
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} else {
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a.rs[i].diag("illegal operand types in %s %d of %s\n\t%v\n\t%v", a.errPosName, i+1, a.errOp, lt, rt);
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}
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bad = true;
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}
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}
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if bad {
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return nil;
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}
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// Compile
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return lt, genAssign(lt, r);
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switch {
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case !isMT:
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// Case 1
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return genAssign(lt, a.rs[0]);
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case !isUnpack:
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// Case 2
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as := make([]func(lv Value, f *Frame), len(a.rs));
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for i, r := range a.rs {
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as[i] = genAssign(lmt.Elems[i], r);
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}
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return func(lv Value, f *Frame) {
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lmv := lv.(multiV);
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for i, a := range as {
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a(lmv[i], f);
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}
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};
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default:
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// Case 3
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rf := a.rs[0].asMulti();
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return func(lv Value, f *Frame) {
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lv.Assign(multiV(rf(f)));
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};
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}
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panic();
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}
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// compileAssign compiles an assignment operation without the full
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// generality of an assignCompiler. See assignCompiler for a
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// description of the arguments.
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func (a *compiler) compileAssign(pos token.Position, lt Type, rs []*exprCompiler, errOp, errPosName string) (func(lv Value, f *Frame)) {
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ac, ok := a.checkAssign(pos, rs, errOp, errPosName);
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if !ok {
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return nil;
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}
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return ac.compile(lt);
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}
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/*
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@ -342,6 +479,10 @@ func (a *exprCompiler) DoIdent(x *ast.Ident) {
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a.diag("variable %s used in constant expression", x.Value);
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return;
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}
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if def.Type == nil {
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// Placeholder definition from an earlier error
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return;
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}
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a.t = def.Type;
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defidx := def.Index;
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a.genIdentOp(dscope, defidx);
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@ -611,51 +752,37 @@ func (a *exprCompiler) DoCallExpr(x *ast.CallExpr) {
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return;
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}
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if len(as) != len(lt.In) {
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msg := "too many";
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if len(as) < len(lt.In) {
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msg = "not enough";
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}
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a.diag("%s arguments to call\n\t%s\n\t%s", msg, typeListString(lt.In, nil), typeListString(ats, nil));
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return;
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}
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// The arguments must be single-valued expressions assignment
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// compatible with the parameters of F.
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afs := make([]func(lv Value, f *Frame), len(as));
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for i := 0; i < len(as); i++ {
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var at Type;
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at, afs[i] = mkAssign(lt.In[i], as[i], "function call", "argument", i + 1);
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if at == nil {
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bad = true;
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}
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}
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if bad {
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//
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// XXX(Spec) The spec is wrong. It can also be a single
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// multi-valued expression.
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assign := a.compileAssign(x.Pos(), NewMultiType(lt.In), as, "function call", "argument");
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if assign == nil {
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return;
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}
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nResults := len(lt.Out);
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if nResults != 1 {
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log.Crashf("Multi-valued return type not implemented");
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nout := len(lt.Out);
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switch nout {
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case 0:
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a.t = EmptyType;
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case 1:
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a.t = lt.Out[0];
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default:
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a.t = NewMultiType(lt.Out);
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}
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a.t = lt.Out[0];
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// Compile
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lf := l.asFunc();
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nin := len(lt.In);
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call := func(f *Frame) []Value {
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fun := lf(f);
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fr := fun.NewFrame();
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for i, af := range afs {
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af(fr.Vars[i], f);
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}
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assign(multiV(fr.Vars[0:nin]), f);
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fun.Call(fr);
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return fr.Vars[len(afs):len(afs)+nResults];
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return fr.Vars[nin:nin+nout];
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};
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a.genFuncCall(call);
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// Function calls, method calls, and channel operations can
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// appear in statement context.
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a.exec = func(f *Frame) { call(f) };
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}
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func (a *exprCompiler) DoStarExpr(x *ast.StarExpr) {
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@ -1150,9 +1277,9 @@ func (a *exprCompiler) extractEffect() (func(f *Frame), *exprCompiler) {
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addr.t = tempType;
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addr.genUnaryAddrOf(a);
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_, assign := mkAssign(tempType, addr, "", "", 0);
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assign := a.compileAssign(a.pos, tempType, []*exprCompiler{addr}, "", "");
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if assign == nil {
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log.Crashf("extractEffect: mkAssign type check failed");
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log.Crashf("compileAssign type check failed");
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}
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effect := func(f *Frame) {
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@ -1311,6 +1438,7 @@ func (a *exprCompiler) genIndexArray(l *exprCompiler, r *exprCompiler) {
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}
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func (a *exprCompiler) genFuncCall(call func(f *Frame) []Value) {
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a.exec = func(f *Frame) { call(f) };
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switch _ := a.t.rep().(type) {
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case *boolType:
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a.evalBool = func(f *Frame) bool { return call(f)[0].(BoolValue).Get() };
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@ -1328,6 +1456,8 @@ func (a *exprCompiler) genFuncCall(call func(f *Frame) []Value) {
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a.evalPtr = func(f *Frame) Value { return call(f)[0].(PtrValue).Get() };
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case *FuncType:
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a.evalFunc = func(f *Frame) Func { return call(f)[0].(FuncValue).Get() };
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case *MultiType:
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a.evalMulti = func(f *Frame) []Value { return call(f) };
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default:
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log.Crashf("unexpected result type %v at %v", a.t, a.pos);
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}
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@ -91,21 +91,27 @@ func (a *stmtCompiler) doAssign(s *ast.AssignStmt) {
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}
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}
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// Check the assignment count
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if len(s.Lhs) != len(s.Rhs) {
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log.Crashf("Unbalanced assignment not implemented %v %v %v", len(s.Lhs), s.Tok, len(s.Rhs));
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errOp := "assignment";
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if s.Tok == token.DEFINE {
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errOp = "definition";
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}
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ac, ok := a.checkAssign(s.Pos(), rs, "assignment", "value");
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if !ok {
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bad = true;
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}
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// Compile left side and generate assigners
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// If this is a definition and the LHS is too big, we won't be
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// able to produce the usual error message because we can't
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// begin to infer the types of the LHS.
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if s.Tok == token.DEFINE && len(s.Lhs) > len(ac.rmt.Elems) {
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a.diag("not enough values for definition");
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bad = true;
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}
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// Compile left side
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ls := make([]*exprCompiler, len(s.Lhs));
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as := make([]func(lv Value, f *Frame), len(s.Lhs));
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nDefs := 0;
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for i, le := range s.Lhs {
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errPos := i + 1;
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if len(s.Lhs) == 1 {
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errPos = 0;
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}
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if s.Tok == token.DEFINE {
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// Check that it's an identifier
|
||||
ident, ok := le.(*ast.Ident);
|
||||
@ -123,17 +129,39 @@ func (a *stmtCompiler) doAssign(s *ast.AssignStmt) {
|
||||
}
|
||||
nDefs++;
|
||||
|
||||
if rs[i] == nil {
|
||||
// TODO(austin) Define a placeholder.
|
||||
continue;
|
||||
}
|
||||
|
||||
// Generate assigner and get type
|
||||
// Compute the identifier's type from the RHS
|
||||
// type. We use the computed MultiType so we
|
||||
// don't have to worry about unpacking.
|
||||
var lt Type;
|
||||
lt, as[i] = mkAssign(nil, rs[i], "assignment", "position", errPos);
|
||||
if lt == nil {
|
||||
bad = true;
|
||||
continue;
|
||||
switch {
|
||||
case i >= len(ac.rmt.Elems):
|
||||
// Define a placeholder. We already
|
||||
// gave the "not enough" error above.
|
||||
lt = nil;
|
||||
|
||||
case ac.rmt.Elems[i] == nil:
|
||||
// We gave the error when we compiled
|
||||
// the RHS.
|
||||
lt = nil;
|
||||
|
||||
case ac.rmt.Elems[i].isIdeal():
|
||||
// If the type is absent and the
|
||||
// corresponding expression is a
|
||||
// constant expression of ideal
|
||||
// integer or ideal float type, the
|
||||
// type of the declared variable is
|
||||
// int or float respectively.
|
||||
switch {
|
||||
case ac.rmt.Elems[i].isInteger():
|
||||
lt = IntType;
|
||||
case ac.rmt.Elems[i].isFloat():
|
||||
lt = FloatType;
|
||||
default:
|
||||
log.Crashf("unexpected ideal type %v", rs[i].t);
|
||||
}
|
||||
|
||||
default:
|
||||
lt = ac.rmt.Elems[i];
|
||||
}
|
||||
|
||||
// Define identifier
|
||||
@ -155,16 +183,6 @@ func (a *stmtCompiler) doAssign(s *ast.AssignStmt) {
|
||||
bad = true;
|
||||
continue;
|
||||
}
|
||||
|
||||
// Generate assigner
|
||||
if as[i] == nil {
|
||||
var lt Type;
|
||||
lt, as[i] = mkAssign(ls[i].t, rs[i], "assignment", "position", errPos);
|
||||
if lt == nil {
|
||||
bad = true;
|
||||
continue;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// A short variable declaration may redeclare variables
|
||||
@ -180,23 +198,58 @@ func (a *stmtCompiler) doAssign(s *ast.AssignStmt) {
|
||||
return;
|
||||
}
|
||||
|
||||
// Create assigner
|
||||
var lt Type;
|
||||
n := len(s.Lhs);
|
||||
if n == 1 {
|
||||
lf := ls[0].evalAddr;
|
||||
assign := as[0];
|
||||
a.push(func(v *vm) { assign(lf(v.f), v.f) });
|
||||
lt = ls[0].t;
|
||||
} else {
|
||||
a.push(func(v *vm) {
|
||||
temps := make([]Value, n);
|
||||
// Assign to temporaries
|
||||
for i := 0; i < n; i++ {
|
||||
// TODO(austin) Don't capture ls
|
||||
temps[i] = ls[i].t.Zero();
|
||||
as[i](temps[i], v.f);
|
||||
lts := make([]Type, len(ls));
|
||||
for i, l := range ls {
|
||||
if l != nil {
|
||||
lts[i] = l.t;
|
||||
}
|
||||
}
|
||||
lt = NewMultiType(lts);
|
||||
}
|
||||
assign := ac.compile(lt);
|
||||
if assign == nil {
|
||||
return;
|
||||
}
|
||||
|
||||
// Compile
|
||||
if n == 1 {
|
||||
// Don't need temporaries and can avoid []Value.
|
||||
lf := ls[0].evalAddr;
|
||||
a.push(func(v *vm) { assign(lf(v.f), v.f) });
|
||||
} else if s.Tok == token.DEFINE && nDefs == n {
|
||||
// Don't need temporaries
|
||||
lfs := make([]func(*Frame) Value, n);
|
||||
for i, l := range ls {
|
||||
lfs[i] = l.evalAddr;
|
||||
}
|
||||
a.push(func(v *vm) {
|
||||
dest := make([]Value, n);
|
||||
for i, lf := range lfs {
|
||||
dest[i] = lf(v.f);
|
||||
}
|
||||
assign(multiV(dest), v.f);
|
||||
});
|
||||
} else {
|
||||
// Need temporaries
|
||||
lmt := lt.(*MultiType);
|
||||
lfs := make([]func(*Frame) Value, n);
|
||||
for i, l := range ls {
|
||||
lfs[i] = l.evalAddr;
|
||||
}
|
||||
a.push(func(v *vm) {
|
||||
temp := lmt.Zero().(multiV);
|
||||
assign(temp, v.f);
|
||||
// Copy to destination
|
||||
for i := 0; i < n; i++ {
|
||||
ls[i].evalAddr(v.f).Assign(temps[i]);
|
||||
for i := 0; i < n; i ++ {
|
||||
// TODO(austin) Need to evaluate LHS
|
||||
// before RHS
|
||||
lfs[i](v.f).Assign(temp[i]);
|
||||
}
|
||||
});
|
||||
}
|
||||
@ -244,9 +297,9 @@ func (a *stmtCompiler) doAssignOp(s *ast.AssignStmt) {
|
||||
return;
|
||||
}
|
||||
|
||||
_, assign := mkAssign(l.t, binop, "assignment", "", 0);
|
||||
assign := a.compileAssign(s.Pos(), l.t, []*exprCompiler{binop}, "assignment", "value");
|
||||
if assign == nil {
|
||||
return;
|
||||
log.Crashf("compileAssign type check failed");
|
||||
}
|
||||
|
||||
lf := l.evalAddr;
|
||||
@ -280,58 +333,46 @@ func (a *stmtCompiler) DoReturnStmt(s *ast.ReturnStmt) {
|
||||
// return statement.
|
||||
a.returned = true;
|
||||
|
||||
if len(s.Results) == 0 && (len(a.outVars) == 0 || a.outVarsNamed) {
|
||||
if len(s.Results) == 0 && (len(a.fnType.Out) == 0 || a.outVarsNamed) {
|
||||
// Simple case. Simply exit from the function.
|
||||
a.push(func(v *vm) { v.pc = ^uint(0) });
|
||||
a.err = false;
|
||||
return;
|
||||
}
|
||||
|
||||
// TODO(austin) Might be a call of a multi-valued function.
|
||||
// It might be possible to combine this code with the
|
||||
// assignment code.
|
||||
if len(s.Results) != len(a.outVars) {
|
||||
a.diag("Unbalanced return not implemented");
|
||||
return;
|
||||
}
|
||||
|
||||
// Compile expressions and create assigners
|
||||
// Compile expressions
|
||||
bad := false;
|
||||
rs := make([]*exprCompiler, len(s.Results));
|
||||
as := make([]func(lv Value, f *Frame), len(s.Results));
|
||||
for i, re := range s.Results {
|
||||
rs[i] = a.compileExpr(a.scope, re, false);
|
||||
if rs[i] == nil {
|
||||
bad = true;
|
||||
continue;
|
||||
}
|
||||
|
||||
errPos := i + 1;
|
||||
if len(s.Results) == 1 {
|
||||
errPos = 0;
|
||||
}
|
||||
var lt Type;
|
||||
lt, as[i] = mkAssign(a.outVars[i].Type, rs[i], "return", "value", errPos);
|
||||
if as[i] == nil {
|
||||
bad = true;
|
||||
}
|
||||
}
|
||||
|
||||
if bad {
|
||||
return;
|
||||
}
|
||||
|
||||
// Save indexes of return values
|
||||
idxs := make([]int, len(s.Results));
|
||||
for i, outVar := range a.outVars {
|
||||
idxs[i] = outVar.Index;
|
||||
// Create assigner
|
||||
|
||||
// However, if the expression list in the "return" statement
|
||||
// is a single call to a multi-valued function, the values
|
||||
// returned from the called function will be returned from
|
||||
// this one.
|
||||
assign := a.compileAssign(s.Pos(), NewMultiType(a.fnType.Out), rs, "return", "value");
|
||||
if assign == nil {
|
||||
return;
|
||||
}
|
||||
|
||||
// XXX(Spec) "The result types of the current function and the
|
||||
// called function must match." Match is fuzzy. It should
|
||||
// say that they must be assignment compatible.
|
||||
|
||||
// Compile
|
||||
start := len(a.fnType.In);
|
||||
nout := len(a.fnType.Out);
|
||||
a.push(func(v *vm) {
|
||||
for i, assign := range as {
|
||||
assign(v.activation.Vars[idxs[i]], v.f);
|
||||
}
|
||||
assign(multiV(v.activation.Vars[start:start+nout]), v.f);
|
||||
v.pc = ^uint(0);
|
||||
});
|
||||
a.err = false;
|
||||
@ -410,19 +451,17 @@ func (a *compiler) compileFunc(scope *Scope, decl *FuncDecl, body *ast.BlockStmt
|
||||
for i, t := range decl.Type.In {
|
||||
bodyScope.DefineVar(decl.InNames[i].Value, t);
|
||||
}
|
||||
outVars := make([]*Variable, len(decl.Type.Out));
|
||||
for i, t := range decl.Type.Out {
|
||||
if decl.OutNames[i] != nil {
|
||||
outVars[i] = bodyScope.DefineVar(decl.OutNames[i].Value, t);
|
||||
bodyScope.DefineVar(decl.OutNames[i].Value, t);
|
||||
} else {
|
||||
// TODO(austin) It would be nice to have a
|
||||
// better way to define unnamed slots.
|
||||
outVars[i] = bodyScope.DefineVar(":out" + strconv.Itoa(i), t);
|
||||
// TODO(austin) Not technically a temp
|
||||
bodyScope.DefineTemp(t);
|
||||
}
|
||||
}
|
||||
|
||||
// Create block context
|
||||
fc := &funcCompiler{a, outVars, false, newCodeBuf(), false};
|
||||
fc := &funcCompiler{a, decl.Type, false, newCodeBuf(), false};
|
||||
if len(decl.OutNames) > 0 && decl.OutNames[0] != nil {
|
||||
fc.outVarsNamed = true;
|
||||
}
|
||||
|
||||
@ -45,8 +45,11 @@ type typeArrayMap map[uintptr] *typeArrayMapEntry
|
||||
func hashTypeArray(key []Type) uintptr {
|
||||
hash := uintptr(0);
|
||||
for _, t := range key {
|
||||
addr := reflect.NewValue(t).Addr();
|
||||
hash = hash * 33;
|
||||
if t == nil {
|
||||
continue;
|
||||
}
|
||||
addr := reflect.NewValue(t).Addr();
|
||||
hash ^= addr;
|
||||
}
|
||||
return hash;
|
||||
@ -153,7 +156,6 @@ type uintType struct {
|
||||
Bits uint;
|
||||
// true for uintptr, false for all others
|
||||
Ptr bool;
|
||||
|
||||
name string;
|
||||
}
|
||||
|
||||
@ -224,7 +226,6 @@ type intType struct {
|
||||
|
||||
// 0 for architecture-dependent types
|
||||
Bits uint;
|
||||
|
||||
name string;
|
||||
}
|
||||
|
||||
@ -437,10 +438,8 @@ func (t *stringType) Zero() Value
|
||||
|
||||
type ArrayType struct {
|
||||
commonType;
|
||||
|
||||
Len int64;
|
||||
Elem Type;
|
||||
|
||||
lit Type;
|
||||
}
|
||||
|
||||
@ -595,7 +594,12 @@ func typeListString(ts []Type, ns []*ast.Ident) string {
|
||||
if ns != nil && ns[i] != nil {
|
||||
s += ns[i].Value + " ";
|
||||
}
|
||||
s += t.String();
|
||||
if t == nil {
|
||||
// Some places use nil types to represent errors
|
||||
s += "<none>";
|
||||
} else {
|
||||
s += t.String();
|
||||
}
|
||||
}
|
||||
return s;
|
||||
}
|
||||
@ -708,3 +712,55 @@ func (t *NamedType) String() string {
|
||||
func (t *NamedType) Zero() Value {
|
||||
return t.def.Zero();
|
||||
}
|
||||
|
||||
/*
|
||||
* Multi-valued type
|
||||
*/
|
||||
|
||||
// MultiType is a special type used for multi-valued expressions, akin
|
||||
// to a tuple type. It's not generally accessible within the
|
||||
// language.
|
||||
type MultiType struct {
|
||||
commonType;
|
||||
Elems []Type;
|
||||
lit Type;
|
||||
}
|
||||
|
||||
var multiTypes = newTypeArrayMap()
|
||||
|
||||
func NewMultiType(elems []Type) *MultiType {
|
||||
if t := multiTypes.Get(elems); t != nil {
|
||||
return t.(*MultiType);
|
||||
}
|
||||
|
||||
t := &MultiType{commonType{}, elems, nil};
|
||||
multiTypes.Put(elems, t);
|
||||
return t;
|
||||
}
|
||||
|
||||
var EmptyType Type = NewMultiType([]Type{});
|
||||
|
||||
func (t *MultiType) literal() Type {
|
||||
if t.lit == nil {
|
||||
elems := make([]Type, len(t.Elems));
|
||||
for i, e := range t.Elems {
|
||||
elems[i] = e.literal();
|
||||
}
|
||||
|
||||
t.lit = NewMultiType(elems);
|
||||
}
|
||||
return t.lit;
|
||||
}
|
||||
|
||||
func (t *MultiType) rep() Type {
|
||||
return t;
|
||||
}
|
||||
|
||||
func (t *MultiType) String() string {
|
||||
if len(t.Elems) == 0 {
|
||||
return "<none>";
|
||||
}
|
||||
return typeListString(t.Elems, nil);
|
||||
}
|
||||
|
||||
func (t *MultiType) Zero() Value
|
||||
|
||||
@ -536,6 +536,38 @@ func (t *FuncType) Zero() Value {
|
||||
return &funcV{nil};
|
||||
}
|
||||
|
||||
/*
|
||||
* Multi-values
|
||||
*/
|
||||
|
||||
type multiV []Value
|
||||
|
||||
func (v multiV) String() string {
|
||||
res := "(";
|
||||
for i, v := range v {
|
||||
if i > 0 {
|
||||
res += ", ";
|
||||
}
|
||||
res += v.String();
|
||||
}
|
||||
return res + ")";
|
||||
}
|
||||
|
||||
func (v multiV) Assign(o Value) {
|
||||
omv := o.(multiV);
|
||||
for i := range v {
|
||||
v[i].Assign(omv[i]);
|
||||
}
|
||||
}
|
||||
|
||||
func (t *MultiType) Zero() Value {
|
||||
res := make([]Value, len(t.Elems));
|
||||
for i := 0; i < len(t.Elems); i++ {
|
||||
res[i] = t.Elems[i].Zero();
|
||||
}
|
||||
return multiV(res);
|
||||
}
|
||||
|
||||
/*
|
||||
* Universal constants
|
||||
*/
|
||||
|
||||
Loading…
Reference in New Issue
Block a user