Use action function return value to make state jumps happen
- The A_Jump family of action functions now return the state to jump
to (NULL if no jump is to be taken) instead of jumping directly.
It is the caller's responsibility to handle the jump. This will
make it possible to use their results in if statements and
do something other than jump.
- DECORATE return statements can now return the result of a function
(but not any random expression--it must be a function call). To
make a jump happen from inside a multi-action block, you must
return the value of an A_Jump function. e.g.:
{ return A_Jump(128, "SomeState"); }
- The VMFunction class now contains its prototype instead of storing
it at a higher level in PFunction. This is so that
FState::CallAction can easily tell if a function returns a state.
- Removed the FxTailable class because with explicit return
statements, it's not useful anymore.
This commit is contained in:
Randy Heit
parent
0f70d10521
commit
b2ccd0bd28
18 changed files with 662 additions and 534 deletions
|
|
@ -129,6 +129,17 @@ bool FxExpression::isConstant() const
|
|||
//
|
||||
//==========================================================================
|
||||
|
||||
VMFunction *FxExpression::GetDirectFunction()
|
||||
{
|
||||
return NULL;
|
||||
}
|
||||
|
||||
//==========================================================================
|
||||
//
|
||||
//
|
||||
//
|
||||
//==========================================================================
|
||||
|
||||
FxExpression *FxExpression::Resolve(FCompileContext &ctx)
|
||||
{
|
||||
isresolved = true;
|
||||
|
|
@ -3064,28 +3075,6 @@ ExpEmit FxActionSpecialCall::Emit(VMFunctionBuilder *build)
|
|||
return dest;
|
||||
}
|
||||
|
||||
//==========================================================================
|
||||
//
|
||||
//
|
||||
//
|
||||
//==========================================================================
|
||||
|
||||
ExpEmit FxTailable::Emit(VMFunctionBuilder *build)
|
||||
{
|
||||
return Emit(build, false);
|
||||
}
|
||||
|
||||
//==========================================================================
|
||||
//
|
||||
//
|
||||
//
|
||||
//==========================================================================
|
||||
|
||||
VMFunction *FxTailable::GetDirectFunction()
|
||||
{
|
||||
return NULL;
|
||||
}
|
||||
|
||||
//==========================================================================
|
||||
//
|
||||
// FxVMFunctionCall
|
||||
|
|
@ -3093,7 +3082,7 @@ VMFunction *FxTailable::GetDirectFunction()
|
|||
//==========================================================================
|
||||
|
||||
FxVMFunctionCall::FxVMFunctionCall(PFunction *func, FArgumentList *args, const FScriptPosition &pos)
|
||||
: FxTailable(pos)
|
||||
: FxExpression(pos)
|
||||
{
|
||||
Function = func;
|
||||
ArgList = args;
|
||||
|
|
@ -3134,14 +3123,9 @@ FxExpression *FxVMFunctionCall::Resolve(FCompileContext& ctx)
|
|||
delete this;
|
||||
return NULL;
|
||||
}
|
||||
TArray<PType *> &rets = Function->Variants[0].Proto->ReturnTypes;
|
||||
if (rets.Size() == 0)
|
||||
TArray<PType *> &rets = Function->Variants[0].Implementation->Proto->ReturnTypes;
|
||||
if (rets.Size() > 0)
|
||||
{
|
||||
ReturnType = TypeVoid;
|
||||
}
|
||||
else
|
||||
{
|
||||
ReturnType = rets[0];
|
||||
// If more types are added to ParseNativeFunction(), add them here too.
|
||||
if (rets[0] == TypeSInt32) ValueType = VAL_Int;
|
||||
else if (rets[0] == TypeFloat64) ValueType = VAL_Float;
|
||||
|
|
@ -3165,6 +3149,11 @@ FxExpression *FxVMFunctionCall::Resolve(FCompileContext& ctx)
|
|||
//
|
||||
//==========================================================================
|
||||
|
||||
ExpEmit FxVMFunctionCall::Emit(VMFunctionBuilder *build)
|
||||
{
|
||||
return Emit(build, false);
|
||||
}
|
||||
|
||||
ExpEmit FxVMFunctionCall::Emit(VMFunctionBuilder *build, bool tailcall)
|
||||
{
|
||||
assert(build->Registers[REGT_POINTER].GetMostUsed() >= 3);
|
||||
|
|
@ -3191,17 +3180,17 @@ ExpEmit FxVMFunctionCall::Emit(VMFunctionBuilder *build, bool tailcall)
|
|||
}
|
||||
}
|
||||
// Get a constant register for this function
|
||||
int funcaddr = build->GetConstantAddress(Function->Variants[0].Implementation, ATAG_OBJECT);
|
||||
VMFunction *vmfunc = Function->Variants[0].Implementation;
|
||||
int funcaddr = build->GetConstantAddress(vmfunc, ATAG_OBJECT);
|
||||
// Emit the call
|
||||
if (tailcall)
|
||||
{ // Tail call
|
||||
build->Emit(OP_TAIL_K, funcaddr, count, 0);
|
||||
return ExpEmit();
|
||||
}
|
||||
else if (ReturnType != TypeVoid)
|
||||
else if (vmfunc->Proto->ReturnTypes.Size() > 0)
|
||||
{ // Call, expecting one result
|
||||
assert(ReturnType != NULL);
|
||||
ExpEmit reg(build, ReturnType->GetRegType());
|
||||
ExpEmit reg(build, vmfunc->Proto->ReturnTypes[0]->GetRegType());
|
||||
build->Emit(OP_CALL_K, funcaddr, count, 1);
|
||||
build->Emit(OP_RESULT, 0, reg.RegType, reg.RegNum);
|
||||
return reg;
|
||||
|
|
@ -3331,7 +3320,7 @@ FxExpression *FxSequence::Resolve(FCompileContext &ctx)
|
|||
CHECKRESOLVED();
|
||||
for (unsigned i = 0; i < Expressions.Size(); ++i)
|
||||
{
|
||||
if (NULL == (Expressions[i] = static_cast<FxTailable *>(Expressions[i]->Resolve(ctx))))
|
||||
if (NULL == (Expressions[i] = Expressions[i]->Resolve(ctx)))
|
||||
{
|
||||
delete this;
|
||||
return NULL;
|
||||
|
|
@ -3346,11 +3335,11 @@ FxExpression *FxSequence::Resolve(FCompileContext &ctx)
|
|||
//
|
||||
//==========================================================================
|
||||
|
||||
ExpEmit FxSequence::Emit(VMFunctionBuilder *build, bool tailcall)
|
||||
ExpEmit FxSequence::Emit(VMFunctionBuilder *build)
|
||||
{
|
||||
for (unsigned i = 0; i < Expressions.Size(); ++i)
|
||||
{
|
||||
ExpEmit v = Expressions[i]->Emit(build, tailcall ? i == Expressions.Size()-1 : false);
|
||||
ExpEmit v = Expressions[i]->Emit(build);
|
||||
// Throw away any result. We don't care about it.
|
||||
v.Free(build);
|
||||
}
|
||||
|
|
@ -3378,9 +3367,9 @@ VMFunction *FxSequence::GetDirectFunction()
|
|||
//
|
||||
//==========================================================================
|
||||
|
||||
FxIfStatement::FxIfStatement(FxExpression *cond, FxTailable *true_part,
|
||||
FxTailable *false_part, const FScriptPosition &pos)
|
||||
: FxTailable(pos)
|
||||
FxIfStatement::FxIfStatement(FxExpression *cond, FxExpression *true_part,
|
||||
FxExpression *false_part, const FScriptPosition &pos)
|
||||
: FxExpression(pos)
|
||||
{
|
||||
Condition = cond;
|
||||
WhenTrue = true_part;
|
||||
|
|
@ -3407,12 +3396,12 @@ FxExpression *FxIfStatement::Resolve(FCompileContext &ctx)
|
|||
ABORT(Condition);
|
||||
if (WhenTrue != NULL)
|
||||
{
|
||||
WhenTrue = static_cast<FxTailable *>(WhenTrue->Resolve(ctx));
|
||||
WhenTrue = WhenTrue->Resolve(ctx);
|
||||
ABORT(WhenTrue);
|
||||
}
|
||||
if (WhenFalse != NULL)
|
||||
{
|
||||
WhenFalse = static_cast<FxTailable *>(WhenFalse->Resolve(ctx));
|
||||
WhenFalse = WhenFalse->Resolve(ctx);
|
||||
ABORT(WhenFalse);
|
||||
}
|
||||
ValueType = VAL_Unknown;
|
||||
|
|
@ -3422,7 +3411,7 @@ FxExpression *FxIfStatement::Resolve(FCompileContext &ctx)
|
|||
ExpVal condval = static_cast<FxConstant *>(Condition)->GetValue();
|
||||
bool result = condval.GetBool();
|
||||
|
||||
FxTailable *e = result ? WhenTrue : WhenFalse;
|
||||
FxExpression *e = result ? WhenTrue : WhenFalse;
|
||||
delete (result ? WhenFalse : WhenTrue);
|
||||
WhenTrue = WhenFalse = NULL;
|
||||
delete this;
|
||||
|
|
@ -3431,11 +3420,11 @@ FxExpression *FxIfStatement::Resolve(FCompileContext &ctx)
|
|||
return this;
|
||||
}
|
||||
|
||||
ExpEmit FxIfStatement::Emit(VMFunctionBuilder *build, bool tailcall)
|
||||
ExpEmit FxIfStatement::Emit(VMFunctionBuilder *build)
|
||||
{
|
||||
ExpEmit v;
|
||||
size_t jumpspot;
|
||||
FxTailable *path1, *path2;
|
||||
FxExpression *path1, *path2;
|
||||
int condcheck;
|
||||
|
||||
// This is pretty much copied from FxConditional, except we don't
|
||||
|
|
@ -3465,24 +3454,18 @@ ExpEmit FxIfStatement::Emit(VMFunctionBuilder *build, bool tailcall)
|
|||
cond.Free(build);
|
||||
|
||||
// Evaluate first path
|
||||
v = path1->Emit(build, tailcall);
|
||||
v = path1->Emit(build);
|
||||
v.Free(build);
|
||||
if (path2 != NULL)
|
||||
{
|
||||
size_t path1jump = build->Emit(OP_JMP, 0);
|
||||
// Evaluate second path
|
||||
build->BackpatchToHere(jumpspot);
|
||||
v = path2->Emit(build, tailcall);
|
||||
v = path2->Emit(build);
|
||||
v.Free(build);
|
||||
jumpspot = path1jump;
|
||||
}
|
||||
build->BackpatchToHere(jumpspot);
|
||||
if (tailcall)
|
||||
{
|
||||
// When tailcall is true, execution is not expected to get past
|
||||
// this if statement, so issue a RET.
|
||||
build->Emit(OP_RET, RET_FINAL, REGT_NIL, 0);
|
||||
}
|
||||
return ExpEmit();
|
||||
}
|
||||
|
||||
|
|
@ -3490,14 +3473,35 @@ ExpEmit FxIfStatement::Emit(VMFunctionBuilder *build, bool tailcall)
|
|||
//
|
||||
//==========================================================================
|
||||
|
||||
FxReturnStatement::FxReturnStatement(const FScriptPosition &pos)
|
||||
: FxTailable(pos)
|
||||
FxReturnStatement::FxReturnStatement(FxVMFunctionCall *call, const FScriptPosition &pos)
|
||||
: FxExpression(pos), Call(call)
|
||||
{
|
||||
}
|
||||
|
||||
ExpEmit FxReturnStatement::Emit(VMFunctionBuilder *build, bool tailcall)
|
||||
FxExpression *FxReturnStatement::Resolve(FCompileContext &ctx)
|
||||
{
|
||||
build->Emit(OP_RET, RET_FINAL, REGT_NIL, 0);
|
||||
CHECKRESOLVED();
|
||||
if (Call != NULL)
|
||||
{
|
||||
Call = static_cast<FxVMFunctionCall *>(Call->Resolve(ctx));
|
||||
ABORT(Call);
|
||||
}
|
||||
return this;
|
||||
}
|
||||
|
||||
ExpEmit FxReturnStatement::Emit(VMFunctionBuilder *build)
|
||||
{
|
||||
// If we return nothing, use a regular RET opcode. If we return
|
||||
// something, use TAIL to call the function. Our return type
|
||||
// should be compatible with the called function's return type.
|
||||
if (Call == NULL)
|
||||
{
|
||||
build->Emit(OP_RET, RET_FINAL, REGT_NIL, 0);
|
||||
}
|
||||
else
|
||||
{
|
||||
Call->Emit(build, true);
|
||||
}
|
||||
return ExpEmit();
|
||||
}
|
||||
|
||||
|
|
|
|||
Loading…
Add table
Add a link
Reference in a new issue