ack/lang/pc/comp/tmpvar.C
2006-02-04 00:57:05 +00:00

128 lines
2.1 KiB
C

/* T E M P O R A R Y V A R I A B L E S */
/* Code for the allocation and de-allocation of temporary variables,
allowing re-use.
The routines use "ProcScope" instead of "CurrentScope", because
"CurrentScope" also reflects WITH statements, and these scopes do not
have local variables.
*/
#include "debug.h"
#include <alloc.h>
#include <em_arith.h>
#include <em_label.h>
#include <em_reg.h>
#include "def.h"
#include "main.h"
#include "scope.h"
#include "type.h"
struct tmpvar {
struct tmpvar *next;
arith t_offset; /* offset from LocalBase */
};
/* ALLOCDEF "tmpvar" 10 */
static struct tmpvar *TmpInts, /* for integer temporaries */
*TmpPtrs; /* for pointer temporaries */
static struct scope *ProcScope; /* scope of procedure in which the
temporaries are allocated
*/
TmpOpen(sc)
struct scope *sc;
{
/* Initialize for temporaries in scope "sc".
*/
ProcScope = sc;
}
arith
TmpSpace(sz, al)
arith sz;
{
register struct scope *sc = ProcScope;
sc->sc_off = - WA(align(sz - sc->sc_off, al));
return sc->sc_off;
}
STATIC arith
NewTmp(plist, sz, al, regtype, priority)
struct tmpvar **plist;
arith sz;
{
register arith offset;
register struct tmpvar *tmp;
if( !*plist ) {
offset = TmpSpace(sz, al);
if( !options['n'] ) C_ms_reg(offset, sz, regtype, priority);
}
else {
tmp = *plist;
offset = tmp->t_offset;
*plist = tmp->next;
free_tmpvar(tmp);
}
return offset;
}
arith
NewInt(reg_prior)
{
return NewTmp(&TmpInts, int_size, int_align, reg_any, reg_prior);
}
arith
NewPtr(reg_prior)
{
return NewTmp(&TmpPtrs, pointer_size, pointer_align, reg_pointer, reg_prior);
}
STATIC
FreeTmp(plist, off)
struct tmpvar **plist;
arith off;
{
register struct tmpvar *tmp = new_tmpvar();
tmp->next = *plist;
tmp->t_offset = off;
*plist = tmp;
}
FreeInt(off)
arith off;
{
FreeTmp(&TmpInts, off);
}
FreePtr(off)
arith off;
{
FreeTmp(&TmpPtrs, off);
}
TmpClose()
{
register struct tmpvar *tmp, *tmp1;
tmp = TmpInts;
while( tmp ) {
tmp1 = tmp;
tmp = tmp->next;
free_tmpvar(tmp1);
}
tmp = TmpPtrs;
while( tmp ) {
tmp1 = tmp;
tmp = tmp->next;
free_tmpvar(tmp1);
}
TmpInts = TmpPtrs = 0;
}