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Been hacking at Nasal recently:

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Fix bug with break/continue inside of a foreach or forindex: Don't pop
the vector/index inside OP_EACH, do it at the end of the loop.

In the process, discovered and fixed a scary corruption issue with
continue; it never really worked right, although simple usage was
likely to get away without crashing.  Both the continue's OP_BREAK and
the cleanup code at the end of a loop would pop the "mark" stack,
leading to an underflow.  Introduced an OP_CONTINUE which adjusts
stack but doesn't change markTop

Re-inline the PUSH macro.  This thing is called all over the place
from the inner loop.  If the problem is intra-expression side effects,
then just use another expression in the macro.

Return an empty vector when requesting zero-length subvec, not nil

Have call() return the call stack in the error vector; see docs on
plausible.org/nasal or ask Andy about this feature.

Default closure()'s level argument to zero, not nil

Add an optional "file name" argument to compile()
This commit is contained in:
andy
2006-07-03 05:13:27 +00:00
parent 735f475c24
commit d894f52b97
6 changed files with 41 additions and 57 deletions
Download Patch File Download Diff File Expand all files Collapse all files

34
simgear/nasal/code.c
View File

@@ -200,29 +200,15 @@ void naFreeContext(struct Context* c)
UNLOCK();
}
#if 0
/*
* This is the original code which might not work properly on all
* platforms since it allows one to work on the same variable in one
* statement without the prior knowledge how this will behave.
*
* e.g. ctx->opStack[ctx->opTop++] = ctx->opStack[ctx->opTop-1];
* ^^^^^ ^^^^^
*/
# define PUSH(r) do { \
// Note that opTop is incremented separately, to avoid situations
// where the "r" expression also references opTop. The SGI compiler
// is known to have issues with such code.
#define PUSH(r) do { \
if(ctx->opTop >= MAX_STACK_DEPTH) ERR(ctx, "stack overflow"); \
ctx->opStack[ctx->opTop++] = r; \
ctx->opStack[ctx->opTop] = r; \
ctx->opTop++; \
} while(0)
#else
# define PUSH(r) _PUSH((ctx), (r))
void _PUSH(struct Context* ctx, naRef r) {
if(ctx->opTop >= MAX_STACK_DEPTH) ERR(ctx, "stack overflow");
ctx->opStack[ctx->opTop++] = r;
}
#endif
static void setupArgs(naContext ctx, struct Frame* f, naRef* args, int nargs)
{
int i;
@@ -402,15 +388,14 @@ static int getMember(struct Context* ctx, naRef obj, naRef fld,
}
// OP_EACH works like a vector get, except that it leaves the vector
// and index on the stack, increments the index after use, and pops
// the arguments and pushes a nil if the index is beyond the end.
// and index on the stack, increments the index after use, and
// pushes a nil if the index is beyond the end.
static void evalEach(struct Context* ctx, int useIndex)
{
int idx = (int)(ctx->opStack[ctx->opTop-1].num);
naRef vec = ctx->opStack[ctx->opTop-2];
if(!IS_VEC(vec)) naRuntimeError(ctx, "foreach enumeration of non-vector");
if(!vec.ref.ptr.vec->rec || idx >= vec.ref.ptr.vec->rec->size) {
ctx->opTop -= 2; // pop two values
PUSH(naNil());
return;
}
@@ -618,6 +603,9 @@ static naRef run(struct Context* ctx)
case OP_BREAK: // restore stack state (FOLLOW WITH JMP!)
ctx->opTop = ctx->markStack[--ctx->markTop];
break;
case OP_CONTINUE: // same, but don't modify markTop
ctx->opTop = ctx->markStack[ctx->markTop-1];
break;
default:
ERR(ctx, "BUG: bad opcode");
}

2
simgear/nasal/code.h
View File

@@ -22,7 +22,7 @@ enum {
OP_DUP, OP_XCHG, OP_INSERT, OP_EXTRACT, OP_MEMBER, OP_SETMEMBER,
OP_LOCAL, OP_SETLOCAL, OP_NEWVEC, OP_VAPPEND, OP_NEWHASH, OP_HAPPEND,
OP_MARK, OP_UNMARK, OP_BREAK, OP_FTAIL, OP_MTAIL, OP_SETSYM, OP_DUP2,
OP_INDEX
OP_INDEX, OP_CONTINUE
};
struct Frame {

6
simgear/nasal/codegen.c
View File

@@ -480,9 +480,9 @@ static void genForEach(struct Parser* p, struct Token* t)
vec = RIGHT(h);
body = RIGHT(t)->children;
pushLoop(p, label);
genExpr(p, vec);
emit(p, OP_PUSHZERO);
pushLoop(p, label);
loopTop = p->cg->codesz;
emit(p, t->type == TOK_FOREACH ? OP_EACH : OP_INDEX);
jumpEnd = emitJump(p, OP_JIFNIL);
@@ -491,6 +491,8 @@ static void genForEach(struct Parser* p, struct Token* t)
emit(p, assignOp);
emit(p, OP_POP);
genLoop(p, body, 0, label, loopTop, jumpEnd);
emit(p, OP_POP); // Pull off the vector and index
emit(p, OP_POP);
}
static int tokMatch(struct Token* a, struct Token* b)
@@ -518,7 +520,7 @@ static void genBreakContinue(struct Parser* p, struct Token* t)
bp = p->cg->loops[p->cg->loopTop - levels].breakIP;
cp = p->cg->loops[p->cg->loopTop - levels].contIP;
for(i=0; i<levels; i++)
emit(p, OP_BREAK);
emit(p, (t->type == TOK_BREAK || i>0) ? OP_BREAK : OP_CONTINUE);
if(t->type == TOK_BREAK)
emit(p, OP_PUSHNIL); // breakIP is always a JIFNOT/JIFNIL!
emitImmediate(p, OP_JMP, t->type == TOK_BREAK ? bp : cp);

27
simgear/nasal/gc.c
View File

@@ -136,28 +136,15 @@ static void naGhost_gcclean(struct naGhost* g)
static void freeelem(struct naPool* p, struct naObj* o)
{
// Free any intrinsic (i.e. non-garbage collected) storage the
// object might have
// Clean up any intrinsic storage the object might have...
switch(p->type) {
case T_STR:
naStr_gcclean((struct naStr*)o);
break;
case T_VEC:
naVec_gcclean((struct naVec*)o);
break;
case T_HASH:
naHash_gcclean((struct naHash*)o);
break;
case T_CODE:
naCode_gcclean((struct naCode*)o);
break;
case T_GHOST:
naGhost_gcclean((struct naGhost*)o);
break;
case T_STR: naStr_gcclean ((struct naStr*) o); break;
case T_VEC: naVec_gcclean ((struct naVec*) o); break;
case T_HASH: naHash_gcclean ((struct naHash*) o); break;
case T_CODE: naCode_gcclean ((struct naCode*) o); break;
case T_GHOST: naGhost_gcclean((struct naGhost*)o); break;
}
// And add it to the free list
p->free[p->nfree++] = o;
p->free[p->nfree++] = o; // ...and add it to the free list
}
static void newBlock(struct naPool* p, int need)

23
simgear/nasal/lib.c
View File

@@ -67,7 +67,7 @@ static naRef subvec(naContext c, naRef me, int argc, naRef* args)
nlen = argc > 2 ? naNumValue(args[2]) : naNil();
if(!naIsNil(nlen))
len = (int)nlen.num;
if(!naIsVector(v) || start < 0 || start >= naVec_size(v) || len < 0)
if(!naIsVector(v) || start < 0 || start > naVec_size(v) || len < 0)
return naNil();
if(naIsNil(nlen) || len > naVec_size(v) - start)
len = naVec_size(v) - start;
@@ -180,8 +180,8 @@ static naRef f_compile(naContext c, naRef me, int argc, naRef* args)
int errLine;
naRef script, code, fname;
script = argc > 0 ? args[0] : naNil();
if(!naIsString(script)) return naNil();
fname = NEWCSTR(c, "<compile>");
fname = argc > 1 ? args[1] : NEWCSTR(c, "<compile>");
if(!naIsString(script) || !naIsString(fname)) return naNil();
code = naParseCode(c, fname, 1,
naStr_data(script), naStr_len(script), &errLine);
if(!naIsCode(code)) return naNil(); // FIXME: export error to caller...
@@ -208,9 +208,17 @@ static naRef f_call(naContext c, naRef me, int argc, naRef* args)
callme, callns);
c->callChild = 0;
if(argc > 2 && IS_VEC(args[argc-1])) {
if(!IS_NIL(subc->dieArg)) naVec_append(args[argc-1], subc->dieArg);
naRef v = args[argc-1];
if(!IS_NIL(subc->dieArg)) naVec_append(v, subc->dieArg);
else if(naGetError(subc))
naVec_append(args[argc-1], NEWCSTR(subc, naGetError(subc)));
naVec_append(v, NEWCSTR(subc, naGetError(subc)));
if(naVec_size(v)) {
int i, sd = naStackDepth(subc);
for(i=0; i<sd; i++) {
naVec_append(v, naGetSourceFile(subc, i));
naVec_append(v, naNum(naGetLine(subc, i)));
}
}
}
naFreeContext(subc);
return result;
@@ -349,10 +357,9 @@ static naRef f_caller(naContext ctx, naRef me, int argc, naRef* args)
static naRef f_closure(naContext ctx, naRef me, int argc, naRef* args)
{
int i;
naRef func, idx;
struct naFunc* f;
func = argc > 0 ? args[0] : naNil();
idx = argc > 1 ? naNumValue(args[1]) : naNil();
naRef func = argc > 0 ? args[0] : naNil();
naRef idx = argc > 1 ? naNumValue(args[1]) : naNum(0);
if(!IS_FUNC(func) || IS_NIL(idx))
naRuntimeError(ctx, "bad arguments to closure()");
i = (int)idx.num;

6
simgear/nasal/vector.c
View File

@@ -13,7 +13,7 @@ static struct VecRec* newvecrec(struct VecRec* old)
return vr;
}
static void vecrealloc(struct naVec* v)
static void resize(struct naVec* v)
{
struct VecRec* vr = newvecrec(v->rec);
naGC_swapfree((void**)&(v->rec), vr);
@@ -60,7 +60,7 @@ int naVec_append(naRef vec, naRef o)
if(IS_VEC(vec)) {
struct VecRec* r = vec.ref.ptr.vec->rec;
while(!r || r->size >= r->alloced) {
vecrealloc(vec.ref.ptr.vec);
resize(vec.ref.ptr.vec);
r = vec.ref.ptr.vec->rec;
}
r->array[r->size] = o;
@@ -91,7 +91,7 @@ naRef naVec_removelast(naRef vec)
o = v->array[v->size - 1];
v->size--;
if(v->size < (v->alloced >> 1))
vecrealloc(vec.ref.ptr.vec);
resize(vec.ref.ptr.vec);
return o;
}
return naNil();