abi.KindOf; llgo/ssa: valFromData

This commit is contained in:
xushiwei
2024-05-24 00:36:51 +08:00
parent 4986592dd7
commit 176c0b2d36
2 changed files with 137 additions and 76 deletions

View File

@@ -24,6 +24,57 @@ import (
"hash"
)
// -----------------------------------------------------------------------------
type Kind int
const (
Invalid Kind = iota
Indirect // allocate memory for the value
Pointer // store a pointer value directly in the interface value
Integer // store a integer value directly in the interface value
BitCast // store other value (need bitcast) directly in the interface value
)
func KindOf(raw types.Type, is32Bits bool) (ret Kind) {
switch t := raw.Underlying().(type) {
case *types.Basic:
kind := t.Kind()
switch {
case types.Bool <= kind && kind <= types.Uintptr:
if is32Bits && (kind == types.Int64 || kind == types.Uint64) {
return Indirect
}
return Integer
case kind == types.Float32:
return BitCast
case kind == types.Float64 || kind == types.Complex64:
if is32Bits {
return Indirect
}
return BitCast
case kind == types.UnsafePointer:
return Pointer
}
case *types.Pointer, *types.Signature, *types.Map, *types.Chan:
return Pointer
case *types.Struct:
if t.NumFields() == 1 {
return KindOf(t.Field(0).Type(), is32Bits)
}
case *types.Interface, *types.Slice:
case *types.Array:
if t.Len() == 1 {
return KindOf(t.Elem(), is32Bits)
}
default:
panic("unkown type")
}
return Indirect
}
// -----------------------------------------------------------------------------
// Builder is a helper for constructing ABI types.
type Builder struct {
h hash.Hash
@@ -95,3 +146,5 @@ func (b *Builder) structHash(t *types.Struct) (ret []byte, private bool) {
ret = h.Sum(b.buf[:0])
return
}
// -----------------------------------------------------------------------------

View File

@@ -178,6 +178,90 @@ func (b Builder) makeIntfByIntptr(tinter Type, rawIntf *types.Interface, typ Typ
panic("todo")
}
func (b Builder) valFromData(t Type, data Expr) Expr {
kind := abi.KindOf(t.raw.Type, b.Prog.is32Bits)
switch kind {
case abi.Indirect:
impl := b.impl
tll := t.ll
tptr := llvm.PointerType(tll, 0)
ptr := llvm.CreatePointerCast(impl, data.impl, tptr)
return Expr{llvm.CreateLoad(impl, tll, ptr), t}
case abi.Pointer:
return Expr{data.impl, t}
case abi.Integer:
x := castUintptr(b, data.impl, b.Prog.Uintptr())
return Expr{castInt(b, x, t), t}
case abi.BitCast:
x := castUintptr(b, data.impl, b.Prog.Uintptr())
return Expr{llvm.CreateBitCast(b.impl, x, t.ll), t}
}
panic("todo")
}
// The TypeAssert instruction tests whether interface value X has type
// AssertedType.
//
// If !CommaOk, on success it returns v, the result of the conversion
// (defined below); on failure it panics.
//
// If CommaOk: on success it returns a pair (v, true) where v is the
// result of the conversion; on failure it returns (z, false) where z
// is AssertedType's zero value. The components of the pair must be
// accessed using the Extract instruction.
//
// If Underlying: tests whether interface value X has the underlying
// type AssertedType.
//
// If AssertedType is a concrete type, TypeAssert checks whether the
// dynamic type in interface X is equal to it, and if so, the result
// of the conversion is a copy of the value in the interface.
//
// If AssertedType is an interface, TypeAssert checks whether the
// dynamic type of the interface is assignable to it, and if so, the
// result of the conversion is a copy of the interface value X.
// If AssertedType is a superinterface of X.Type(), the operation will
// fail iff the operand is nil. (Contrast with ChangeInterface, which
// performs no nil-check.)
//
// Type() reflects the actual type of the result, possibly a
// 2-types.Tuple; AssertedType is the asserted type.
//
// Depending on the TypeAssert's purpose, Pos may return:
// - the ast.CallExpr.Lparen of an explicit T(e) conversion;
// - the ast.TypeAssertExpr.Lparen of an explicit e.(T) operation;
// - the ast.CaseClause.Case of a case of a type-switch statement;
// - the Ident(m).NamePos of an interface method value i.m
// (for which TypeAssert may be used to effect the nil check).
//
// Example printed form:
//
// t1 = typeassert t0.(int)
// t3 = typeassert,ok t2.(T)
func (b Builder) TypeAssert(x Expr, assertedTyp Type, commaOk bool) Expr {
if debugInstr {
log.Printf("TypeAssert %v, %v, %v\n", x.impl, assertedTyp.raw.Type, commaOk)
}
tx := b.faceAbiType(x)
tabi := b.abiType(assertedTyp.raw.Type)
eq := b.BinOp(token.EQL, tx, tabi)
if commaOk {
prog := b.Prog
t := prog.Tuple(assertedTyp, prog.Bool())
val := b.valFromData(assertedTyp, b.InterfaceData(x))
zero := prog.Zero(assertedTyp)
valTrue := aggregateValue(b.impl, t.ll, val.impl, prog.BoolVal(true).impl)
valFalse := aggregateValue(b.impl, t.ll, zero.impl, prog.BoolVal(false).impl)
return Expr{llvm.CreateSelect(b.impl, eq.impl, valTrue, valFalse), t}
}
blks := b.Func.MakeBlocks(2)
b.If(eq, blks[0], blks[1])
b.SetBlock(blks[1])
b.Panic(b.Str("type assertion failed"))
b.SetBlock(blks[0])
return b.valFromData(assertedTyp, b.InterfaceData(x))
}
/*
func (b Builder) TypeAssert(x Expr, assertedTyp Type, commaOk bool) (ret Expr) {
if debugInstr {
@@ -246,82 +330,6 @@ func (b Builder) TypeAssert(x Expr, assertedTyp Type, commaOk bool) (ret Expr) {
}
*/
// The TypeAssert instruction tests whether interface value X has type
// AssertedType.
//
// If !CommaOk, on success it returns v, the result of the conversion
// (defined below); on failure it panics.
//
// If CommaOk: on success it returns a pair (v, true) where v is the
// result of the conversion; on failure it returns (z, false) where z
// is AssertedType's zero value. The components of the pair must be
// accessed using the Extract instruction.
//
// If Underlying: tests whether interface value X has the underlying
// type AssertedType.
//
// If AssertedType is a concrete type, TypeAssert checks whether the
// dynamic type in interface X is equal to it, and if so, the result
// of the conversion is a copy of the value in the interface.
//
// If AssertedType is an interface, TypeAssert checks whether the
// dynamic type of the interface is assignable to it, and if so, the
// result of the conversion is a copy of the interface value X.
// If AssertedType is a superinterface of X.Type(), the operation will
// fail iff the operand is nil. (Contrast with ChangeInterface, which
// performs no nil-check.)
//
// Type() reflects the actual type of the result, possibly a
// 2-types.Tuple; AssertedType is the asserted type.
//
// Depending on the TypeAssert's purpose, Pos may return:
// - the ast.CallExpr.Lparen of an explicit T(e) conversion;
// - the ast.TypeAssertExpr.Lparen of an explicit e.(T) operation;
// - the ast.CaseClause.Case of a case of a type-switch statement;
// - the Ident(m).NamePos of an interface method value i.m
// (for which TypeAssert may be used to effect the nil check).
//
// Example printed form:
//
// t1 = typeassert t0.(int)
// t3 = typeassert,ok t2.(T)
func (b Builder) TypeAssert(x Expr, assertedTyp Type, commaOk bool) Expr {
if debugInstr {
log.Printf("TypeAssert %v, %v, %v\n", x.impl, assertedTyp.raw.Type, commaOk)
}
tx := b.faceAbiType(x)
tabi := b.abiType(assertedTyp.raw.Type)
eq := b.BinOp(token.EQL, tx, tabi)
if commaOk {
prog := b.Prog
t := prog.Tuple(assertedTyp, prog.Bool())
val := b.valFromData(assertedTyp, b.InterfaceData(x))
zero := prog.Zero(assertedTyp)
valTrue := aggregateValue(b.impl, t.ll, val.impl, prog.BoolVal(true).impl)
valFalse := aggregateValue(b.impl, t.ll, zero.impl, prog.BoolVal(false).impl)
return Expr{llvm.CreateSelect(b.impl, eq.impl, valTrue, valFalse), t}
}
blks := b.Func.MakeBlocks(2)
b.If(eq, blks[0], blks[1])
b.SetBlock(blks[1])
b.Panic(b.Str("type assertion failed"))
b.SetBlock(blks[0])
return b.valFromData(assertedTyp, b.InterfaceData(x))
}
func (b Builder) valFromData(t Type, data Expr) Expr {
switch u := t.raw.Type.Underlying().(type) {
case *types.Basic:
kind := u.Kind()
switch {
case kind >= types.Bool && kind <= types.Uintptr:
panic("todo")
}
}
_ = data
panic("todo")
}
// -----------------------------------------------------------------------------
// InterfaceData returns the data pointer of an interface.