Files
simgear/simgear/nasal/codegen.c

819 lines
26 KiB
C

#include <string.h>
#include "parse.h"
#include "code.h"
#define MAX_FUNARGS 32
// These are more sensical predicate names in most contexts in this file
#define LEFT(tok) ((tok)->children)
#define RIGHT(tok) ((tok)->lastChild)
#define UNARY(tok) (LEFT(tok) && LEFT(tok) == RIGHT(tok))
#define BINARY(tok) (LEFT(tok) && RIGHT(tok) && LEFT(tok)->next == RIGHT(tok))
// Forward references for recursion
static void genExpr(struct Parser* p, struct Token* t);
static void genExprList(struct Parser* p, struct Token* t);
static naRef newLambda(struct Parser* p, struct Token* t);
static void emit(struct Parser* p, int val)
{
if(p->cg->codesz >= p->cg->codeAlloced) {
int i, sz = p->cg->codeAlloced * 2;
unsigned short* buf = naParseAlloc(p, sz*sizeof(unsigned short));
for(i=0; i<p->cg->codeAlloced; i++) buf[i] = p->cg->byteCode[i];
p->cg->byteCode = buf;
p->cg->codeAlloced = sz;
}
p->cg->byteCode[p->cg->codesz++] = (unsigned short)val;
}
static void emitImmediate(struct Parser* p, int val, int arg)
{
emit(p, val);
emit(p, arg);
}
static void genBinOp(int op, struct Parser* p, struct Token* t)
{
if(!LEFT(t) || !RIGHT(t))
naParseError(p, "empty subexpression", t->line);
genExpr(p, LEFT(t));
genExpr(p, RIGHT(t));
emit(p, op);
}
static int newConstant(struct Parser* p, naRef c)
{
int i;
naVec_append(p->cg->consts, c);
i = naVec_size(p->cg->consts) - 1;
if(i > 0xffff) naParseError(p, "too many constants in code block", 0);
return i;
}
// Interns a scalar (!) constant and returns its index
static int internConstant(struct Parser* p, naRef c)
{
int i, n = naVec_size(p->cg->consts);
if(IS_CODE(c)) return newConstant(p, c);
for(i=0; i<n; i++) {
naRef b = naVec_get(p->cg->consts, i);
if(IS_NUM(b) && IS_NUM(c) && b.num == c.num) return i;
else if(IS_NIL(b) && IS_NIL(c)) return i;
else if(naStrEqual(b, c)) return i;
}
return newConstant(p, c);
}
/* FIXME: this API is fundamentally a resource leak, because symbols
* can't be deregistered. The "proper" way to do this would be to
* keep a reference count for each symbol, and decrement it when a
* code object referencing it is deleted. */
naRef naInternSymbol(naRef sym)
{
naRef result;
if(naHash_get(globals->symbols, sym, &result))
return result;
naHash_set(globals->symbols, sym, sym);
return sym;
}
static int findConstantIndex(struct Parser* p, struct Token* t)
{
naRef c, dummy;
if(t->type == TOK_NIL) c = naNil();
else if(t->str) {
c = naStr_fromdata(naNewString(p->context), t->str, t->strlen);
naHash_get(globals->symbols, c, &dummy); // noop, make c immutable
if(t->type == TOK_SYMBOL) c = naInternSymbol(c);
} else if(t->type == TOK_FUNC) c = newLambda(p, t);
else if(t->type == TOK_LITERAL) c = naNum(t->num);
else {
naParseError(p, "invalid/non-constant constant", t->line);
/* naParseError() doesn't return, but this stops compiler complaining
about <c> not being set. */
return -1;
}
return internConstant(p, c);
}
static int genScalarConstant(struct Parser* p, struct Token* t)
{
int idx;
if(t->str == 0 && t->num == 1) { emit(p, OP_PUSHONE); return 0; }
if(t->str == 0 && t->num == 0) { emit(p, OP_PUSHZERO); return 0; }
emitImmediate(p, OP_PUSHCONST, idx = findConstantIndex(p, t));
return idx;
}
static int genLValue(struct Parser* p, struct Token* t, int* cidx)
{
if(!t) naParseError(p, "bad lvalue", -1);
if(t->type == TOK_LPAR && t->rule != PREC_SUFFIX) {
return genLValue(p, LEFT(t), cidx); // Handle stuff like "(a) = 1"
} else if(t->type == TOK_SYMBOL) {
*cidx = genScalarConstant(p, t);
return OP_SETSYM;
} else if(t->type == TOK_DOT && RIGHT(t) && RIGHT(t)->type == TOK_SYMBOL) {
genExpr(p, LEFT(t));
*cidx = genScalarConstant(p, RIGHT(t));
return OP_SETMEMBER;
} else if(t->type == TOK_LBRA) {
genExpr(p, LEFT(t));
genExpr(p, RIGHT(t));
return OP_INSERT;
} else if(t->type == TOK_VAR && RIGHT(t) && RIGHT(t)->type == TOK_SYMBOL) {
*cidx = genScalarConstant(p, RIGHT(t));
return OP_SETLOCAL;
} else {
naParseError(p, "bad lvalue", t->line);
return -1;
}
}
static void genEqOp(int op, struct Parser* p, struct Token* t)
{
int cidx, n = 2, setop = genLValue(p, LEFT(t), &cidx);
if(setop == OP_SETMEMBER) {
emit(p, OP_DUP2);
emit(p, OP_POP);
emitImmediate(p, OP_MEMBER, cidx);
} else if(setop == OP_INSERT) {
emit(p, OP_DUP2);
emit(p, OP_EXTRACT);
} else {
emitImmediate(p, OP_LOCAL, cidx);
n = 1;
}
genExpr(p, RIGHT(t));
emit(p, op);
emit(p, n == 1 ? OP_XCHG : OP_XCHG2);
emit(p, setop);
}
static int defArg(struct Parser* p, struct Token* t)
{
if(t->type == TOK_LPAR) {
// http://code.google.com/p/flightgear-bugs/issues/detail?id=737
// TOK_LPAR can mean multi-value assignment or function call,
// disambigaute by checking the rule of the token
if (t->rule == PREC_SUFFIX)
naParseError(p, "default arguments cannot be function calls", t->line);
return defArg(p, RIGHT(t));
}
if(t->type == TOK_MINUS && RIGHT(t) &&
RIGHT(t)->type == TOK_LITERAL && !RIGHT(t)->str)
{
/* default arguments are constants, but "-1" parses as two
* tokens, so we have to subset the expression generator for that
* case */
RIGHT(t)->num *= -1;
return defArg(p, RIGHT(t));
}
if(t->type == TOK_CAT && RIGHT(t) &&
RIGHT(t)->type == TOK_LITERAL && !RIGHT(t)->str)
{
/* default arguments are constants, but "~1" parses as two
* tokens, so we have to subset the expression generator for that
* case */
RIGHT(t)->num = ~(int)RIGHT(t)->num;
return defArg(p, RIGHT(t));
}
return findConstantIndex(p, t);
}
static void genArgList(struct Parser* p, struct naCode* c, struct Token* t)
{
naRef sym;
if(t->type == TOK_EMPTY) return;
if(!IDENTICAL(p->cg->restArgSym, globals->argRef))
naParseError(p, "remainder must be last", t->line);
if(t->type == TOK_ELLIPSIS) {
if(LEFT(t)->type != TOK_SYMBOL)
naParseError(p, "bad function argument expression", t->line);
sym = naStr_fromdata(naNewString(p->context),
LEFT(t)->str, LEFT(t)->strlen);
p->cg->restArgSym = naInternSymbol(sym);
c->needArgVector = 1;
} else if(t->type == TOK_ASSIGN) {
if(LEFT(t)->type != TOK_SYMBOL)
naParseError(p, "bad function argument expression", t->line);
p->cg->optArgSyms[c->nOptArgs] = findConstantIndex(p, LEFT(t));
p->cg->optArgVals[c->nOptArgs++] = defArg(p, RIGHT(t));
} else if(t->type == TOK_SYMBOL) {
if(c->nOptArgs)
naParseError(p, "optional arguments must be last", t->line);
if(c->nArgs >= MAX_FUNARGS)
naParseError(p, "too many named function arguments", t->line);
p->cg->argSyms[c->nArgs++] = findConstantIndex(p, t);
} else if(t->type == TOK_COMMA) {
if(!LEFT(t) || !RIGHT(t))
naParseError(p, "empty function argument", t->line);
genArgList(p, c, LEFT(t));
genArgList(p, c, RIGHT(t));
} else
naParseError(p, "bad function argument expression", t->line);
}
static naRef newLambda(struct Parser* p, struct Token* t)
{
struct CodeGenerator* cgSave;
naRef codeObj;
struct Token* arglist;
if(RIGHT(t)->type != TOK_LCURL)
naParseError(p, "bad function definition", t->line);
// Save off the generator state while we do the new one
cgSave = p->cg;
arglist = LEFT(t)->type == TOK_LPAR ? LEFT(LEFT(t)) : 0;
codeObj = naCodeGen(p, LEFT(RIGHT(t)), arglist);
p->cg = cgSave;
return codeObj;
}
static void genLambda(struct Parser* p, struct Token* t)
{
emitImmediate(p, OP_PUSHCONST, newConstant(p, newLambda(p, t)));
}
static int genList(struct Parser* p, struct Token* t, int doAppend)
{
if(!t || t->type == TOK_EMPTY) {
return 0;
} else if(t->type == TOK_COMMA) {
genExpr(p, LEFT(t));
if(doAppend) emit(p, OP_VAPPEND);
return 1 + genList(p, RIGHT(t), doAppend);
} else {
genExpr(p, t);
if(doAppend) emit(p, OP_VAPPEND);
return 1;
}
}
static void genHashElem(struct Parser* p, struct Token* t)
{
if(!t || t->type == TOK_EMPTY)
return;
if(t->type != TOK_COLON || !LEFT(t))
naParseError(p, "bad hash/object initializer", t->line);
if(LEFT(t)->type == TOK_SYMBOL) genScalarConstant(p, LEFT(t));
else if(LEFT(t)->type == TOK_LITERAL) genExpr(p, LEFT(t));
else naParseError(p, "bad hash/object initializer", t->line);
genExpr(p, RIGHT(t));
emit(p, OP_HAPPEND);
}
static void genHash(struct Parser* p, struct Token* t)
{
if(t && t->type == TOK_COMMA) {
genHashElem(p, LEFT(t));
genHash(p, RIGHT(t));
} else if(t && t->type != TOK_EMPTY) {
genHashElem(p, t);
}
}
static int isHashcall(struct Parser* p, struct Token* t)
{
if(t) {
int sep = LEFT(t) && t->type == TOK_COMMA ? t->children->type : t->type;
return sep == TOK_COLON;
}
return 0;
}
static void genFuncall(struct Parser* p, struct Token* t)
{
int method = 0;
if(LEFT(t)->type == TOK_DOT) {
method = 1;
genExpr(p, LEFT(LEFT(t)));
emit(p, OP_DUP);
emitImmediate(p, OP_MEMBER, findConstantIndex(p, RIGHT(LEFT(t))));
} else {
genExpr(p, LEFT(t));
}
if(isHashcall(p, RIGHT(t))) {
emit(p, OP_NEWHASH);
genHash(p, RIGHT(t));
emit(p, method ? OP_MCALLH : OP_FCALLH);
} else {
int nargs = genList(p, RIGHT(t), 0);
emitImmediate(p, method ? OP_MCALL : OP_FCALL, nargs);
}
}
static int startLoop(struct Parser* p, struct Token* label)
{
int i = p->cg->loopTop;
p->cg->loops[i].breakIP = 0xffffff;
p->cg->loops[i].contIP = 0xffffff;
p->cg->loops[i].label = label;
p->cg->loopTop++;
emit(p, OP_MARK);
return p->cg->codesz;
}
// Emit a jump operation, and return the location of the address in
// the bytecode for future fixup in fixJumpTarget
static int emitJump(struct Parser* p, int op)
{
int ip;
emit(p, op);
ip = p->cg->codesz;
emit(p, 0xffff); // dummy address
return ip;
}
// Points a previous jump instruction at the current "end-of-bytecode"
static void fixJumpTarget(struct Parser* p, int spot)
{
p->cg->byteCode[spot] = p->cg->codesz;
}
static void genShortCircuit(struct Parser* p, struct Token* t)
{
int end;
genExpr(p, LEFT(t));
end = emitJump(p, t->type == TOK_AND ? OP_JIFNOT : OP_JIFTRUE);
emit(p, OP_POP);
genExpr(p, RIGHT(t));
fixJumpTarget(p, end);
}
static void genIf(struct Parser* p, struct Token* tif, struct Token* telse)
{
int jumpNext, jumpEnd;
genExpr(p, tif->children); // the test
jumpNext = emitJump(p, OP_JIFNOTPOP);
genExprList(p, tif->children->next->children); // the body
jumpEnd = emitJump(p, OP_JMP);
fixJumpTarget(p, jumpNext);
if(telse) {
if(telse->type == TOK_ELSIF) genIf(p, telse, telse->next);
else genExprList(p, telse->children->children);
} else {
emit(p, OP_PUSHNIL);
}
fixJumpTarget(p, jumpEnd);
}
static void genIfElse(struct Parser* p, struct Token* t)
{
genIf(p, t, t->children->next->next);
}
static void genQuestion(struct Parser* p, struct Token* t)
{
int jumpNext, jumpEnd;
if(!RIGHT(t) || RIGHT(t)->type != TOK_COLON)
naParseError(p, "invalid ?: expression", t->line);
genExpr(p, LEFT(t)); // the test
jumpNext = emitJump(p, OP_JIFNOTPOP);
genExpr(p, LEFT(RIGHT(t))); // the "if true" expr
jumpEnd = emitJump(p, OP_JMP);
fixJumpTarget(p, jumpNext);
genExpr(p, RIGHT(RIGHT(t))); // the "else" expr
fixJumpTarget(p, jumpEnd);
}
static int countList(struct Token* t, int type)
{
int n;
for(n = 1; t && t->type == type; t = RIGHT(t)) n++;
return n;
}
static void genLoop(struct Parser* p, struct Token* body,
struct Token* update, struct Token* label,
int loopTop, int jumpEnd)
{
int cont, jumpOverContinue;
p->cg->loops[p->cg->loopTop-1].breakIP = jumpEnd-1;
jumpOverContinue = emitJump(p, OP_JMP);
p->cg->loops[p->cg->loopTop-1].contIP = p->cg->codesz;
cont = emitJump(p, OP_JMP);
fixJumpTarget(p, jumpOverContinue);
genExprList(p, body);
emit(p, OP_POP);
fixJumpTarget(p, cont);
if(update) { genExpr(p, update); emit(p, OP_POP); }
emitImmediate(p, OP_JMPLOOP, loopTop);
fixJumpTarget(p, jumpEnd);
p->cg->loopTop--;
emit(p, OP_UNMARK);
emit(p, OP_PUSHNIL); // Leave something on the stack
}
static void genForWhile(struct Parser* p, struct Token* init,
struct Token* test, struct Token* update,
struct Token* body, struct Token* label)
{
int loopTop, jumpEnd;
if(init) { genExpr(p, init); emit(p, OP_POP); }
loopTop = startLoop(p, label);
genExpr(p, test);
jumpEnd = emitJump(p, OP_JIFNOTPOP);
genLoop(p, body, update, label, loopTop, jumpEnd);
}
static void genWhile(struct Parser* p, struct Token* t)
{
struct Token *test=LEFT(t)->children, *body, *label=0;
int len = countList(test, TOK_SEMI);
if(len == 2) {
label = LEFT(test);
if(!label || label->type != TOK_SYMBOL)
naParseError(p, "bad loop label", t->line);
test = RIGHT(test);
} else if(len != 1)
naParseError(p, "too many semicolons in while test", t->line);
body = LEFT(RIGHT(t));
genForWhile(p, 0, test, 0, body, label);
}
static void genFor(struct Parser* p, struct Token* t)
{
struct Token *init, *test, *body, *update, *label=0;
struct Token *h = LEFT(t)->children;
int len = countList(h, TOK_SEMI);
if(len == 4) {
if(!LEFT(h) || LEFT(h)->type != TOK_SYMBOL)
naParseError(p, "bad loop label", h->line);
label = LEFT(h);
h=RIGHT(h);
} else if(len != 3)
naParseError(p, "wrong number of terms in for header", t->line);
init = LEFT(h);
test = LEFT(RIGHT(h));
update = RIGHT(RIGHT(h));
body = RIGHT(t)->children;
genForWhile(p, init, test, update, body, label);
}
static void genForEach(struct Parser* p, struct Token* t)
{
int loopTop, jumpEnd, assignOp, dummy;
struct Token *elem, *body, *vec, *label=0;
struct Token *h = LEFT(LEFT(t));
int len = countList(h, TOK_SEMI);
if(len == 3) {
if(!LEFT(h) || LEFT(h)->type != TOK_SYMBOL)
naParseError(p, "bad loop label", h->line);
label = LEFT(h);
h = RIGHT(h);
} else if (len != 2) {
naParseError(p, "wrong number of terms in foreach header", t->line);
}
elem = LEFT(h);
vec = RIGHT(h);
body = RIGHT(t)->children;
genExpr(p, vec);
emit(p, OP_PUSHZERO);
loopTop = startLoop(p, label);
emit(p, t->type == TOK_FOREACH ? OP_EACH : OP_INDEX);
jumpEnd = emitJump(p, OP_JIFEND);
assignOp = genLValue(p, elem, &dummy);
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)
{
int i, l = a->strlen;
if(!a || !b) return 0;
if(l != b->strlen) return 0;
for(i=0; i<l; i++) if(a->str[i] != b->str[i]) return 0;
return 1;
}
static void genBreakContinue(struct Parser* p, struct Token* t)
{
int levels = 1, loop = -1, bp, cp, i;
// http://code.google.com/p/flightgear-bugs/issues/detail?id=587
// Make sure we are inside of a loop
if(p->cg->loopTop <= 0)
naParseError(p, "break/continue outside of a valid loop", t->line);
if(RIGHT(t)) {
if(RIGHT(t)->type != TOK_SYMBOL)
naParseError(p, "bad break/continue label", t->line);
for(i=0; i<p->cg->loopTop; i++)
if(tokMatch(RIGHT(t), p->cg->loops[i].label))
loop = i;
if(loop == -1)
naParseError(p, "no match for break/continue label", t->line);
levels = p->cg->loopTop - loop;
}
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, (i<levels-1) ? OP_BREAK2 : OP_BREAK);
if(t->type == TOK_BREAK)
emit(p, OP_PUSHEND); // breakIP is always a JIFNOTPOP/JIFEND!
emitImmediate(p, OP_JMP, t->type == TOK_BREAK ? bp : cp);
}
static void newLineEntry(struct Parser* p, int line)
{
int i;
if(p->cg->nextLineIp >= p->cg->nLineIps) {
int nsz = p->cg->nLineIps*2 + 1;
unsigned short* n = naParseAlloc(p, sizeof(unsigned short)*2*nsz);
for(i=0; i<(p->cg->nextLineIp*2); i++)
n[i] = p->cg->lineIps[i];
p->cg->lineIps = n;
p->cg->nLineIps = nsz;
}
p->cg->lineIps[p->cg->nextLineIp++] = (unsigned short) p->cg->codesz;
p->cg->lineIps[p->cg->nextLineIp++] = (unsigned short) line;
}
static int parListLen(struct Token* t)
{
if(t->type != TOK_LPAR || !LEFT(t) || LEFT(t)->type != TOK_COMMA) return 0;
return countList(LEFT(t), TOK_COMMA);
}
static void genCommaList(struct Parser* p, struct Token* t)
{
if(t->type != TOK_COMMA) { genExpr(p, t); return; }
genCommaList(p, RIGHT(t));
genExpr(p, LEFT(t));
}
static void genMultiLV(struct Parser* p, struct Token* t, int var)
{
if(!var) { emit(p, genLValue(p, t, &var)); return; }
if(t->type != TOK_SYMBOL) naParseError(p, "bad lvalue", t->line);
genScalarConstant(p, t);
emit(p, OP_SETLOCAL);
}
static void genAssign(struct Parser* p, struct Token* t)
{
struct Token *lv = LEFT(t), *rv = RIGHT(t);
int len, dummy, var=0;
if (!lv)
naParseError(p, "bad assignment, missing variable", t->line);
else
if(parListLen(lv) || (lv->type == TOK_VAR && parListLen(RIGHT(lv)))) {
if(lv->type == TOK_VAR) { lv = RIGHT(lv); var = 1; }
len = parListLen(lv);
// http://code.google.com/p/flightgear-bugs/issues/detail?id=585
// TOK_LPAR can mean multi-value assignment or function call,
// disambigaute by checking the rule of the token
if(rv->type == TOK_LPAR && rv->rule != PREC_SUFFIX) {
if(len != parListLen(rv))
naParseError(p, "bad assignment count", rv->line);
genCommaList(p, LEFT(rv));
} else {
genExpr(p, rv);
emitImmediate(p, OP_UNPACK, len);
}
for(t = LEFT(lv); t && t->type == TOK_COMMA; t = RIGHT(t)) {
genMultiLV(p, LEFT(t), var);
emit(p, OP_POP);
}
genMultiLV(p, t, var);
} else {
genExpr(p, rv);
emit(p, genLValue(p, lv, &dummy));
}
}
static void genSlice(struct Parser* p, struct Token* t)
{
if(!t || t->type==TOK_EMPTY) naParseError(p, "empty slice expression", -1);
if(t->type == TOK_COLON) {
if(LEFT(t)) genExpr(p, LEFT(t)); else emit(p, OP_PUSHNIL);
if(RIGHT(t)) genExpr(p, RIGHT(t)); else emit(p, OP_PUSHNIL);
emit(p, OP_SLICE2);
} else {
genExpr(p, t);
emit(p, OP_SLICE);
}
}
static void genExtract(struct Parser* p, struct Token* t)
{
genExpr(p, LEFT(t));
if(countList(RIGHT(t), TOK_COMMA) == 1 && RIGHT(t)->type != TOK_COLON) {
genExpr(p, RIGHT(t));
emit(p, OP_EXTRACT);
} else {
emit(p, OP_NEWVEC);
for(t = RIGHT(t); t->type == TOK_COMMA; t = RIGHT(t))
genSlice(p, LEFT(t));
genSlice(p, t);
emit(p, OP_XCHG);
emit(p, OP_POP);
}
}
static void genExpr(struct Parser* p, struct Token* t)
{
int i;
if(!t) naParseError(p, "parse error", -1); // throw line -1...
p->errLine = t->line; // ...to use this one instead
if(t->line != p->cg->lastLine)
newLineEntry(p, t->line);
p->cg->lastLine = t->line;
switch(t->type) {
case TOK_TOP: genExprList(p, LEFT(t)); break;
case TOK_IF: genIfElse(p, t); break;
case TOK_QUESTION: genQuestion(p, t); break;
case TOK_WHILE: genWhile(p, t); break;
case TOK_FOR: genFor(p, t); break;
case TOK_FUNC: genLambda(p, t); break;
case TOK_ASSIGN: genAssign(p, t); break;
case TOK_LITERAL: genScalarConstant(p, t); break;
case TOK_FOREACH: case TOK_FORINDEX:
genForEach(p, t);
break;
case TOK_BREAK: case TOK_CONTINUE:
genBreakContinue(p, t);
break;
case TOK_LPAR:
if(BINARY(t) || !RIGHT(t)) genFuncall(p, t);
else genExpr(p, LEFT(t));
break;
case TOK_LBRA:
if(UNARY(t)) {
emit(p, OP_NEWVEC);
genList(p, LEFT(t), 1);
}
else if(BINARY(t)) {
genExtract(p, t);
} else {
// forbid usage as 'vec[]'
naParseError(p, "missing index or slice expression(s)", t->line);
}
break;
case TOK_LCURL:
emit(p, OP_NEWHASH);
genHash(p, LEFT(t));
break;
case TOK_RETURN:
if(RIGHT(t)) genExpr(p, RIGHT(t));
else emit(p, OP_PUSHNIL);
for(i=0; i<p->cg->loopTop; i++) emit(p, OP_UNMARK);
emit(p, OP_RETURN);
break;
case TOK_NOT:
genExpr(p, RIGHT(t));
emit(p, OP_NOT);
break;
case TOK_SYMBOL:
emitImmediate(p, OP_LOCAL, findConstantIndex(p, t));
break;
case TOK_MINUS:
if(BINARY(t)) {
genBinOp(OP_MINUS, p, t); // binary subtraction
} else if(RIGHT(t) && RIGHT(t)->type == TOK_LITERAL && !RIGHT(t)->str) {
RIGHT(t)->num *= -1; // Pre-negate constants
genScalarConstant(p, RIGHT(t));
} else {
genExpr(p, RIGHT(t)); // unary negation
emit(p, OP_NEG);
}
break;
case TOK_NEG:
genExpr(p, RIGHT(t)); // unary negation (see also TOK_MINUS!)
emit(p, OP_NEG);
break;
case TOK_CAT:
if(BINARY(t)) {
genBinOp(OP_CAT, p, t); // string concatenation
} else if(RIGHT(t) && RIGHT(t)->type == TOK_LITERAL && !RIGHT(t)->str) {
RIGHT(t)->num = ~(int)RIGHT(t)->num; // Pre-negate constants
genScalarConstant(p, RIGHT(t));
} else {
genExpr(p, RIGHT(t)); // unary, bitwise negation
emit(p, OP_BIT_NEG);
}
break;
case TOK_BIT_NEG:
genExpr(p, RIGHT(t)); // unary, bitwise negation (see also TOK_CAT!)
emit(p, OP_BIT_NEG);
break;
case TOK_DOT:
genExpr(p, LEFT(t));
if(!RIGHT(t) || RIGHT(t)->type != TOK_SYMBOL)
naParseError(p, "object field not symbol", RIGHT(t)->line);
emitImmediate(p, OP_MEMBER, findConstantIndex(p, RIGHT(t)));
break;
case TOK_EMPTY: case TOK_NIL:
emit(p, OP_PUSHNIL);
break;
case TOK_AND: case TOK_OR:
genShortCircuit(p, t);
break;
case TOK_BIT_AND:genBinOp(OP_BIT_AND, p, t); break;
case TOK_BIT_OR: genBinOp(OP_BIT_OR, p, t); break;
case TOK_BIT_XOR:genBinOp(OP_BIT_XOR, p, t); break;
case TOK_MUL: genBinOp(OP_MUL, p, t); break;
case TOK_PLUS: genBinOp(OP_PLUS, p, t); break;
case TOK_DIV: genBinOp(OP_DIV, p, t); break;
case TOK_LT: genBinOp(OP_LT, p, t); break;
case TOK_LTE: genBinOp(OP_LTE, p, t); break;
case TOK_EQ: genBinOp(OP_EQ, p, t); break;
case TOK_NEQ: genBinOp(OP_NEQ, p, t); break;
case TOK_GT: genBinOp(OP_GT, p, t); break;
case TOK_GTE: genBinOp(OP_GTE, p, t); break;
case TOK_PLUSEQ: genEqOp(OP_PLUS, p, t); break;
case TOK_MINUSEQ: genEqOp(OP_MINUS, p, t); break;
case TOK_MULEQ: genEqOp(OP_MUL, p, t); break;
case TOK_DIVEQ: genEqOp(OP_DIV, p, t); break;
case TOK_CATEQ: genEqOp(OP_CAT, p, t); break;
case TOK_BIT_ANDEQ: genEqOp(OP_BIT_AND, p, t); break;
case TOK_BIT_OREQ: genEqOp(OP_BIT_OR, p, t); break;
case TOK_BIT_XOREQ: genEqOp(OP_BIT_XOR, p, t); break;
default:
naParseError(p, "parse error", t->line);
};
}
static void genExprList(struct Parser* p, struct Token* t)
{
if(t && t->type == TOK_SEMI) {
genExpr(p, LEFT(t));
if(RIGHT(t) && RIGHT(t)->type != TOK_EMPTY) {
emit(p, OP_POP);
genExprList(p, RIGHT(t));
}
} else {
genExpr(p, t);
}
}
naRef naCodeGen(struct Parser* p, struct Token* block, struct Token* arglist)
{
int i;
naRef codeObj;
struct naCode* code;
struct CodeGenerator cg;
cg.lastLine = 0;
cg.codeAlloced = 1024; // Start fairly big, this is a cheap allocation
cg.byteCode = naParseAlloc(p, cg.codeAlloced *sizeof(unsigned short));
cg.codesz = 0;
cg.consts = naNewVector(p->context);
cg.loopTop = 0;
cg.lineIps = 0;
cg.nLineIps = 0;
cg.nextLineIp = 0;
p->cg = &cg;
genExprList(p, block);
emit(p, OP_RETURN);
// Now make a code object
codeObj = naNewCode(p->context);
code = PTR(codeObj).code;
// Parse the argument list, if any
p->cg->restArgSym = globals->argRef;
code->nArgs = code->nOptArgs = 0;
p->cg->argSyms = p->cg->optArgSyms = p->cg->optArgVals = 0;
code->needArgVector = 1;
if(arglist) {
p->cg->argSyms = naParseAlloc(p, sizeof(int) * MAX_FUNARGS);
p->cg->optArgSyms = naParseAlloc(p, sizeof(int) * MAX_FUNARGS);
p->cg->optArgVals = naParseAlloc(p, sizeof(int) * MAX_FUNARGS);
code->needArgVector = 0;
genArgList(p, code, arglist);
}
code->restArgSym = internConstant(p, p->cg->restArgSym);
/* Set the size fields and allocate the combined array buffer.
* Note cute trick with null pointer to get the array size. */
code->nConstants = naVec_size(cg.consts);
code->codesz = cg.codesz;
code->nLines = cg.nextLineIp;
code->srcFile = p->srcFile;
code->constants = 0;
code->constants = naAlloc((int)(size_t)(LINEIPS(code)+code->nLines));
for(i=0; i<code->nConstants; i++)
code->constants[i] = naVec_get(p->cg->consts, i);
for(i=0; i<code->nArgs; i++) ARGSYMS(code)[i] = cg.argSyms[i];
for(i=0; i<code->nOptArgs; i++) OPTARGSYMS(code)[i] = cg.optArgSyms[i];
for(i=0; i<code->nOptArgs; i++) OPTARGVALS(code)[i] = cg.optArgVals[i];
for(i=0; i<code->codesz; i++) BYTECODE(code)[i] = cg.byteCode[i];
for(i=0; i<code->nLines; i++) LINEIPS(code)[i] = cg.lineIps[i];
return codeObj;
}