symbol *except_gentables()
{
//printf("except_gentables()\n");
#if OUREH
// BUG: alloca() changes the stack size, which is not reflected
// in the fixed eh tables.
assert(!usedalloca);
symbol *s = symbol_generate(SCstatic,tsint);
s->Sseg = UNKNOWN;
symbol_keep(s);
symbol_debug(s);
except_fillInEHTable(s);
outdata(s); // output the scope table
obj_ehtables(funcsym_p,funcsym_p->Ssize,s);
#endif
return NULL;
}
symbol *except_gentables()
{
//printf("except_gentables()\n");
#if TARGET_LINUX || TARGET_OSX || TARGET_FREEBSD || TARGET_SOLARIS
symbol *s;
int sz; // size so far
dt_t **pdt;
unsigned fsize; // target size of function pointer
long spoff;
block *b;
int guarddim;
int i;
// BUG: alloca() changes the stack size, which is not reflected
// in the fixed eh tables.
assert(!usedalloca);
s = symbol_generate(SCstatic,tsint);
s->Sseg = UNKNOWN;
symbol_keep(s);
symbol_debug(s);
fsize = 4;
pdt = &s->Sdt;
sz = 0;
/*
void* pointer to start of function
unsigned offset of ESP from EBP
unsigned offset from start of function to return code
unsigned nguards; // dimension of guard[]
{ unsigned offset; // offset of start of guarded section
unsigned endoffset; // ending offset of guarded section
int last_index; // previous index (enclosing guarded section)
unsigned catchoffset; // offset to catch block from symbol
void *finally; // finally code to execute
} guard[];
catchoffset:
unsigned ncatches; // number of catch blocks
{ void *type; // symbol representing type
unsigned bpoffset; // EBP offset of catch variable
void *handler; // catch handler code
} catch[];
*/
#define GUARD_SIZE 5 // number of 4 byte values in one guard
sz = 0;
// Address of start of function
symbol_debug(funcsym_p);
pdt = dtxoff(pdt,funcsym_p,0,TYnptr);
sz += fsize;
//printf("ehtables: func = %s, offset = x%x, startblock->Boffset = x%x\n", funcsym_p->Sident, funcsym_p->Soffset, startblock->Boffset);
// Get offset of ESP from EBP
spoff = cod3_spoff();
pdt = dtdword(pdt,spoff);
sz += 4;
// Offset from start of function to return code
pdt = dtdword(pdt,retoffset);
sz += 4;
// First, calculate starting catch offset
guarddim = 0; // max dimension of guard[]
for (b = startblock; b; b = b->Bnext)
{
if (b->BC == BC_try && b->Bscope_index >= guarddim)
guarddim = b->Bscope_index + 1;
// printf("b->BC = %2d, Bscope_index = %2d, last_index = %2d, offset = x%x\n",
// b->BC, b->Bscope_index, b->Blast_index, b->Boffset);
}
pdt = dtdword(pdt,guarddim);
sz += 4;
unsigned catchoffset = sz + guarddim * (GUARD_SIZE * 4);
// Generate guard[]
i = 0;
for (b = startblock; b; b = b->Bnext)
{
//printf("b = %p, b->Btry = %p, b->offset = %x\n", b, b->Btry, b->Boffset);
if (b->BC == BC_try)
{ dt_t *dt;
block *bhandler;
int nsucc;
unsigned endoffset;
block *bn;
assert(b->Bscope_index >= i);
if (i < b->Bscope_index)
{ int fillsize = (b->Bscope_index - i) * (GUARD_SIZE * 4);
pdt = dtnzeros(pdt, fillsize);
sz += fillsize;
}
i = b->Bscope_index + 1;
nsucc = list_nitems(b->Bsucc);
pdt = dtdword(pdt,b->Boffset - startblock->Boffset); // offset to start of block
// Compute ending offset
for (bn = b->Bnext; 1; bn = bn->Bnext)
{
//printf("\tbn = %p, bn->Btry = %p, bn->offset = %x\n", bn, bn->Btry, bn->Boffset);
assert(bn);
if (bn->Btry == b->Btry)
{ endoffset = bn->Boffset - startblock->Boffset;
break;
}
}
pdt = dtdword(pdt,endoffset); // offset past end of guarded block
pdt = dtdword(pdt,b->Blast_index); // parent index
if (b->jcatchvar) // if try-catch
{
pdt = dtdword(pdt,catchoffset);
pdt = dtdword(pdt,0); // no finally handler
catchoffset += 4 + (nsucc - 1) * (3 * 4);
}
else // else try-finally
{
assert(nsucc == 2);
pdt = dtdword(pdt,0); // no catch offset
bhandler = list_block(list_next(b->Bsucc));
assert(bhandler->BC == BC_finally);
// To successor of BC_finally block
bhandler = list_block(bhandler->Bsucc);
pdt = dtxoff(pdt,funcsym_p,bhandler->Boffset - startblock->Boffset, TYnptr); // finally handler address
//pdt = dtcoff(pdt,bhandler->Boffset); // finally handler address
}
sz += GUARD_SIZE + 4;
}
}
// Generate catch[]
for (b = startblock; b; b = b->Bnext)
{
if (b->BC == BC_try)
{ block *bhandler;
int nsucc;
if (b->jcatchvar) // if try-catch
{ list_t bl;
nsucc = list_nitems(b->Bsucc);
pdt = dtdword(pdt,nsucc - 1); // # of catch blocks
sz += 4;
for (bl = list_next(b->Bsucc); bl; bl = list_next(bl))
{
block *bcatch = list_block(bl);
pdt = dtxoff(pdt,bcatch->Bcatchtype,0,TYjhandle);
pdt = dtdword(pdt,cod3_bpoffset(b->jcatchvar)); // EBP offset
pdt = dtxoff(pdt,funcsym_p,bcatch->Boffset - startblock->Boffset, TYnptr); // catch handler address
//pdt = dtcoff(pdt,bcatch->Boffset); // catch handler address
sz += 3 * 4;
}
}
}
}
assert(sz != 0);
outdata(s); // output the scope table
obj_ehtables(funcsym_p,funcsym_p->Ssize,s);
#endif
return NULL;
}
