* Make Value smaller by not storing redundant PrimOp info.

* Clear pointers in Values after overwriting them to make sure that no
  objects are kept alive unnecessarily.
This commit is contained in:
Eelco Dolstra 2010-10-23 20:07:47 +00:00
parent 3f66cfb96b
commit 8ac06726b9
2 changed files with 44 additions and 25 deletions

View file

@ -153,15 +153,14 @@ void EvalState::addConstant(const string & name, Value & v)
void EvalState::addPrimOp(const string & name,
unsigned int arity, PrimOp primOp)
unsigned int arity, PrimOpFun primOp)
{
Value * v = allocValue();
string name2 = string(name, 0, 2) == "__" ? string(name, 2) : name;
Symbol sym = symbols.create(name);
v->type = tPrimOp;
v->primOp.arity = arity;
v->primOp.fun = primOp;
v->primOp.name = GC_STRDUP(name2.c_str());
staticBaseEnv.vars[symbols.create(name)] = baseEnvDispl;
v->primOp = new (UseGC) PrimOp(primOp, arity, sym);
staticBaseEnv.vars[sym] = baseEnvDispl;
baseEnv.values[baseEnvDispl++] = v;
(*baseEnv.values[0]->attrs)[symbols.create(name2)].value = v;
}
@ -252,6 +251,7 @@ void mkString(Value & v, const string & s, const PathSet & context)
void mkPath(Value & v, const char * s)
{
clearValue(v);
v.type = tPath;
v.path = GC_STRDUP(s);
}
@ -310,6 +310,7 @@ void EvalState::mkList(Value & v, unsigned int length)
void EvalState::mkAttrs(Value & v)
{
clearValue(v);
v.type = tAttrs;
#if HAVE_BOEHMGC
v.attrs = new (UseGC) Bindings;
@ -595,15 +596,20 @@ void ExprApp::eval(EvalState & state, Env & env, Value & v)
void EvalState::callFunction(Value & fun, Value & arg, Value & v)
{
if (fun.type == tPrimOp || fun.type == tPrimOpApp) {
unsigned int argsLeft =
fun.type == tPrimOp ? fun.primOp.arity : fun.primOpApp.argsLeft;
/* Figure out the number of arguments still needed. */
unsigned int argsDone = 0;
Value * primOp = &fun;
while (primOp->type == tPrimOpApp) {
argsDone++;
primOp = primOp->primOpApp.left;
}
assert(primOp->type == tPrimOp);
unsigned int arity = primOp->primOp->arity;
unsigned int argsLeft = arity - argsDone;
if (argsLeft == 1) {
/* We have all the arguments, so call the primop. First
find the primop. */
Value * primOp = &fun;
while (primOp->type == tPrimOpApp) primOp = primOp->primOpApp.left;
assert(primOp->type == tPrimOp);
unsigned int arity = primOp->primOp.arity;
/* We have all the arguments, so call the primop. */
/* Put all the arguments in an array. */
Value * vArgs[arity];
@ -614,9 +620,9 @@ void EvalState::callFunction(Value & fun, Value & arg, Value & v)
/* And call the primop. */
try {
primOp->primOp.fun(*this, vArgs, v);
primOp->primOp->fun(*this, vArgs, v);
} catch (Error & e) {
addErrorPrefix(e, "while evaluating the builtin function `%1%':\n", primOp->primOp.name);
addErrorPrefix(e, "while evaluating the builtin function `%1%':\n", primOp->primOp->name);
throw;
}
} else {
@ -624,7 +630,6 @@ void EvalState::callFunction(Value & fun, Value & arg, Value & v)
v.primOpApp.left = allocValue();
*v.primOpApp.left = fun;
v.primOpApp.right = &arg;
v.primOpApp.argsLeft = argsLeft - 1;
}
return;
}

View file

@ -44,7 +44,17 @@ typedef enum {
} ValueType;
typedef void (* PrimOp) (EvalState & state, Value * * args, Value & v);
typedef void (* PrimOpFun) (EvalState & state, Value * * args, Value & v);
struct PrimOp
{
PrimOpFun fun;
unsigned int arity;
Symbol name;
PrimOp(PrimOpFun fun, unsigned int arity, Symbol name)
: fun(fun), arity(arity), name(name) { }
};
struct Value
@ -97,15 +107,9 @@ struct Value
Env * env;
ExprLambda * fun;
} lambda;
Value * val;
struct {
PrimOp fun;
char * name;
unsigned int arity;
} primOp;
PrimOp * primOp;
struct {
Value * left, * right;
unsigned int argsLeft;
} primOpApp;
};
};
@ -127,8 +131,17 @@ struct Attr
};
/* After overwriting an app node, be sure to clear pointers in the
Value to ensure that the target isn't kept alive unnecessarily. */
static inline void clearValue(Value & v)
{
v.app.right = 0;
}
static inline void mkInt(Value & v, int n)
{
clearValue(v);
v.type = tInt;
v.integer = n;
}
@ -136,6 +149,7 @@ static inline void mkInt(Value & v, int n)
static inline void mkBool(Value & v, bool b)
{
clearValue(v);
v.type = tBool;
v.boolean = b;
}
@ -268,7 +282,7 @@ private:
void addConstant(const string & name, Value & v);
void addPrimOp(const string & name,
unsigned int arity, PrimOp primOp);
unsigned int arity, PrimOpFun primOp);
Value * lookupVar(Env * env, const VarRef & var);