OpenBSD-4.6/usr.bin/pcc/mips/code.c
/* $OpenBSD: code.c,v 1.6 2008/04/11 20:45:52 stefan Exp $ */
/*
* Copyright (c) 2003 Anders Magnusson (ragge@ludd.luth.se).
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
* MIPS port by Jan Enoksson (janeno-1@student.ltu.se) and
* Simon Olsson (simols-1@student.ltu.se) 2005.
*/
#include <assert.h>
#include "pass1.h"
/*
* Define everything needed to print out some data (or text).
* This means segment, alignment, visibility, etc.
*/
void
defloc(struct symtab *sp)
{
static char *loctbl[] = { "text", "data", "section .rodata" };
static int lastloc = -1;
TWORD t;
int s;
if (sp == NULL) {
lastloc = -1;
return;
}
t = sp->stype;
s = ISFTN(t) ? PROG : ISCON(cqual(t, sp->squal)) ? RDATA : DATA;
lastloc = s;
if (s == PROG)
return; /* text is written in prologue() */
if (s != lastloc)
printf(" .%s\n", loctbl[s]);
printf(" .p2align %d\n", ispow2(talign(t, sp->ssue)));
if (sp->sclass == EXTDEF)
printf(" .globl %s\n", sp->soname);
if (sp->slevel == 0) {
#ifdef USE_GAS
printf("\t.type %s,@object\n", sp->soname);
printf("\t.size %s," CONFMT "\n", sp->soname,
tsize(sp->stype, sp->sdf, sp->ssue));
#endif
printf("%s:\n", sp->soname);
} else
printf(LABFMT ":\n", sp->soffset);
}
#ifdef notdef
/*
* cause the alignment to become a multiple of n
* never called for text segment.
*/
void
defalign(int n)
{
n = ispow2(n / SZCHAR);
if (n == -1)
cerror("defalign: n != 2^i");
printf("\t.p2align %d\n", n);
}
/*
* define the current location as the name p->sname
* never called for text segment.
*/
void
defnam(struct symtab *p)
{
char *c = p->soname;
if (p->sclass == EXTDEF)
printf("\t.globl %s\n", c);
#ifdef USE_GAS
printf("\t.type %s,@object\n", c);
printf("\t.size %s," CONFMT "\n", c, tsize(p->stype, p->sdf, p->ssue));
#endif
printf("%s:\n", c);
}
#endif
static int rvnr;
/*
* code for the end of a function
* deals with struct return here
*/
void
efcode()
{
NODE *p, *q;
int tempnr;
int ty;
if (cftnsp->stype != STRTY+FTN && cftnsp->stype != UNIONTY+FTN)
return;
ty = cftnsp->stype - FTN;
q = block(REG, NIL, NIL, INCREF(ty), 0, cftnsp->ssue);
q->n_rval = V0;
p = tempnode(0, INCREF(ty), 0, cftnsp->ssue);
tempnr = regno(p);
p = buildtree(ASSIGN, p, q);
ecomp(p);
q = tempnode(tempnr, INCREF(ty), 0, cftnsp->ssue);
q = buildtree(UMUL, q, NIL);
p = tempnode(rvnr, INCREF(ty), 0, cftnsp->ssue);
p = buildtree(UMUL, p, NIL);
p = buildtree(ASSIGN, p, q);
ecomp(p);
q = tempnode(rvnr, INCREF(ty), 0, cftnsp->ssue);
p = block(REG, NIL, NIL, INCREF(ty), 0, cftnsp->ssue);
p->n_rval = V0;
p = buildtree(ASSIGN, p, q);
ecomp(p);
}
/* Put a symbol in a temporary
* used by bfcode() and its helpers */
static void
putintemp(struct symtab *sym)
{
NODE *p;
spname = sym;
p = tempnode(0, sym->stype, sym->sdf, sym->ssue);
p = buildtree(ASSIGN, p, buildtree(NAME, 0, 0));
sym->soffset = regno(p->n_left);
sym->sflags |= STNODE;
ecomp(p);
}
/* setup the hidden pointer to struct return parameter
* used by bfcode() */
static void
param_retptr(void)
{
NODE *p, *q;
p = tempnode(0, PTR+STRTY, 0, cftnsp->ssue);
rvnr = regno(p);
q = block(REG, NIL, NIL, PTR+STRTY, 0, cftnsp->ssue);
q->n_rval = A0;
p = buildtree(ASSIGN, p, q);
ecomp(p);
}
/* setup struct parameter
* push the registers out to memory
* used by bfcode() */
static void
param_struct(struct symtab *sym, int *regp)
{
int reg = *regp;
NODE *p, *q;
int navail;
int sz;
int off;
int num;
int i;
navail = nargregs - (reg - A0);
sz = tsize(sym->stype, sym->sdf, sym->ssue) / SZINT;
off = ARGINIT/SZINT + (reg - A0);
num = sz > navail ? navail : sz;
for (i = 0; i < num; i++) {
q = block(REG, NIL, NIL, INT, 0, MKSUE(INT));
q->n_rval = reg++;
p = block(REG, NIL, NIL, INT, 0, MKSUE(INT));
p->n_rval = FP;
p = block(PLUS, p, bcon(4*off++), INT, 0, MKSUE(INT));
p = block(UMUL, p, NIL, INT, 0, MKSUE(INT));
p = buildtree(ASSIGN, p, q);
ecomp(p);
}
*regp = reg;
}
/* setup a 64-bit parameter (double/ldouble/longlong)
* used by bfcode() */
static void
param_64bit(struct symtab *sym, int *regp, int dotemps)
{
int reg = *regp;
NODE *p, *q;
int navail;
/* alignment */
++reg;
reg &= ~1;
navail = nargregs - (reg - A0);
if (navail < 2) {
/* would have appeared half in registers/half
* on the stack, but alignment ensures it
* appears on the stack */
if (dotemps)
putintemp(sym);
*regp = reg;
return;
}
q = block(REG, NIL, NIL, sym->stype, sym->sdf, sym->ssue);
q->n_rval = A0A1 + (reg - A0);
if (dotemps) {
p = tempnode(0, sym->stype, sym->sdf, sym->ssue);
sym->soffset = regno(p);
sym->sflags |= STNODE;
} else {
spname = sym;
p = buildtree(NAME, 0, 0);
}
p = buildtree(ASSIGN, p, q);
ecomp(p);
*regp = reg + 2;
}
/* setup a 32-bit param on the stack
* used by bfcode() */
static void
param_32bit(struct symtab *sym, int *regp, int dotemps)
{
NODE *p, *q;
q = block(REG, NIL, NIL, sym->stype, sym->sdf, sym->ssue);
q->n_rval = (*regp)++;
if (dotemps) {
p = tempnode(0, sym->stype, sym->sdf, sym->ssue);
sym->soffset = regno(p);
sym->sflags |= STNODE;
} else {
spname = sym;
p = buildtree(NAME, 0, 0);
}
p = buildtree(ASSIGN, p, q);
ecomp(p);
}
/*
* XXX This is a hack. We cannot have (l)doubles in more than one
* register class. So we bounce them in and out of temps to
* move them in and out of the right registers.
*/
static void
param_double(struct symtab *sym, int *regp, int dotemps)
{
int reg = *regp;
NODE *p, *q, *t;
int navail;
int tmpnr;
/* alignment */
++reg;
reg &= ~1;
navail = nargregs - (reg - A0);
if (navail < 2) {
/* would have appeared half in registers/half
* on the stack, but alignment ensures it
* appears on the stack */
if (dotemps)
putintemp(sym);
*regp = reg;
return;
}
t = tempnode(0, LONGLONG, 0, MKSUE(LONGLONG));
tmpnr = regno(t);
q = block(REG, NIL, NIL, LONGLONG, 0, MKSUE(LONGLONG));
q->n_rval = A0A1 + (reg - A0);
p = buildtree(ASSIGN, t, q);
ecomp(p);
if (dotemps) {
sym->soffset = tmpnr;
sym->sflags |= STNODE;
} else {
q = tempnode(tmpnr, sym->stype, sym->sdf, sym->ssue);
spname = sym;
p = buildtree(NAME, 0, 0);
p = buildtree(ASSIGN, p, q);
ecomp(p);
}
*regp = reg + 2;
}
/*
* XXX This is a hack. We cannot have floats in more than one
* register class. So we bounce them in and out of temps to
* move them in and out of the right registers.
*/
static void
param_float(struct symtab *sym, int *regp, int dotemps)
{
NODE *p, *q, *t;
int tmpnr;
t = tempnode(0, INT, 0, MKSUE(INT));
tmpnr = regno(t);
q = block(REG, NIL, NIL, INT, 0, MKSUE(INT));
q->n_rval = (*regp)++;
p = buildtree(ASSIGN, t, q);
ecomp(p);
if (dotemps) {
sym->soffset = tmpnr;
sym->sflags |= STNODE;
} else {
q = tempnode(tmpnr, sym->stype, sym->sdf, sym->ssue);
spname = sym;
p = buildtree(NAME, 0, 0);
p = buildtree(ASSIGN, p, q);
ecomp(p);
}
}
/*
* code for the beginning of a function; a is an array of
* indices in symtab for the arguments; n is the number
*/
void
bfcode(struct symtab **sp, int cnt)
{
union arglist *usym;
int lastreg = A0 + nargregs - 1;
int saveallargs = 0;
int i, reg;
/*
* Detect if this function has ellipses and save all
* argument register onto stack.
*/
usym = cftnsp->sdf->dfun;
while (usym && usym->type != TNULL) {
if (usym->type == TELLIPSIS) {
saveallargs = 1;
break;
}
++usym;
}
reg = A0;
/* assign hidden return structure to temporary */
if (cftnsp->stype == STRTY+FTN || cftnsp->stype == UNIONTY+FTN) {
param_retptr();
++reg;
}
/* recalculate the arg offset and create TEMP moves */
for (i = 0; i < cnt; i++) {
if ((reg > lastreg) && !xtemps)
break;
else if (reg > lastreg)
putintemp(sp[i]);
else if (sp[i]->stype == STRTY || sp[i]->stype == UNIONTY)
param_struct(sp[i], ®);
else if (DEUNSIGN(sp[i]->stype) == LONGLONG)
param_64bit(sp[i], ®, xtemps && !saveallargs);
else if (sp[i]->stype == DOUBLE || sp[i]->stype == LDOUBLE)
param_double(sp[i], ®, xtemps && !saveallargs);
else if (sp[i]->stype == FLOAT)
param_float(sp[i], ®, xtemps && !saveallargs);
else
param_32bit(sp[i], ®, xtemps && !saveallargs);
}
/* if saveallargs, save the rest of the args onto the stack */
if (!saveallargs)
return;
while (reg <= lastreg) {
NODE *p, *q;
int off = ARGINIT/SZINT + (reg - A0);
q = block(REG, NIL, NIL, INT, 0, MKSUE(INT));
q->n_rval = reg++;
p = block(REG, NIL, NIL, INT, 0, MKSUE(INT));
p->n_rval = FP;
p = block(PLUS, p, bcon(4*off), INT, 0, MKSUE(INT));
p = block(UMUL, p, NIL, INT, 0, MKSUE(INT));
p = buildtree(ASSIGN, p, q);
ecomp(p);
}
}
/*
* by now, the automatics and register variables are allocated
*/
void
bccode()
{
SETOFF(autooff, SZINT);
}
/* called just before final exit */
/* flag is 1 if errors, 0 if none */
void
ejobcode(int flag )
{
}
void
bjobcode()
{
printf("\t.section .mdebug.abi32\n");
printf("\t.previous\n");
printf("\t.abicalls\n");
}
#ifdef notdef
/*
* Print character t at position i in one string, until t == -1.
* Locctr & label is already defined.
*/
void
bycode(int t, int i)
{
static int lastoctal = 0;
/* put byte i+1 in a string */
if (t < 0) {
if (i != 0)
puts("\\000\"");
} else {
if (i == 0)
printf("\t.ascii \"");
if (t == 0)
return;
else if (t == '\\' || t == '"') {
lastoctal = 0;
putchar('\\');
putchar(t);
} else if (t == 011) {
printf("\\t");
} else if (t == 012) {
printf("\\n");
} else if (t < 040 || t >= 0177) {
lastoctal++;
printf("\\%o",t);
} else if (lastoctal && '0' <= t && t <= '9') {
lastoctal = 0;
printf("\"\n\t.ascii \"%c", t);
} else {
lastoctal = 0;
putchar(t);
}
}
}
#endif
/*
* return the alignment of field of type t
*/
int
fldal(unsigned int t)
{
uerror("illegal field type");
return(ALINT);
}
/* fix up type of field p */
void
fldty(struct symtab *p)
{
}
/*
* XXX - fix genswitch.
*/
int
mygenswitch(int num, TWORD type, struct swents **p, int n)
{
return 0;
}
/* setup call stack with a structure */
/* called from moveargs() */
static NODE *
movearg_struct(NODE *p, NODE *parent, int *regp)
{
int reg = *regp;
NODE *l, *q, *t, *r;
int tmpnr;
int navail;
int off;
int num;
int sz;
int ty;
int i;
navail = nargregs - (reg - A0);
sz = tsize(p->n_type, p->n_df, p->n_sue) / SZINT;
num = sz > navail ? navail : sz;
l = p->n_left;
nfree(p);
ty = l->n_type;
t = tempnode(0, l->n_type, l->n_df, l->n_sue);
tmpnr = regno(t);
l = buildtree(ASSIGN, t, l);
if (p != parent) {
q = parent->n_left;
} else
q = NULL;
/* copy structure into registers */
for (i = 0; i < num; i++) {
t = tempnode(tmpnr, ty, 0, MKSUE(PTR+ty));
t = block(SCONV, t, NIL, PTR+INT, 0, MKSUE(PTR+INT));
t = block(PLUS, t, bcon(4*i), PTR+INT, 0, MKSUE(PTR+INT));
t = buildtree(UMUL, t, NIL);
r = block(REG, NIL, NIL, INT, 0, MKSUE(INT));
r->n_rval = reg++;
r = buildtree(ASSIGN, r, t);
if (q == NULL)
q = r;
else
q = block(CM, q, r, INT, 0, MKSUE(INT));
}
off = ARGINIT/SZINT + nargregs;
for (i = num; i < sz; i++) {
t = tempnode(tmpnr, ty, 0, MKSUE(PTR+ty));
t = block(SCONV, t, NIL, PTR+INT, 0, MKSUE(PTR+INT));
t = block(PLUS, t, bcon(4*i), PTR+INT, 0, MKSUE(PTR+INT));
t = buildtree(UMUL, t, NIL);
r = block(REG, NIL, NIL, INT, 0, MKSUE(INT));
r->n_rval = FP;
r = block(PLUS, r, bcon(4*off++), INT, 0, MKSUE(INT));
r = block(UMUL, r, NIL, INT, 0, MKSUE(INT));
r = buildtree(ASSIGN, r, t);
if (q == NULL)
q = r;
else
q = block(CM, q, r, INT, 0, MKSUE(INT));
}
if (parent->n_op == CM) {
parent->n_left = q;
q = l;
} else {
q = block(CM, q, l, INT, 0, MKSUE(INT));
}
*regp = reg;
return q;
}
/* setup call stack with 64-bit argument */
/* called from moveargs() */
static NODE *
movearg_64bit(NODE *p, int *regp)
{
int reg = *regp;
NODE *q;
int lastarg;
/* alignment */
++reg;
reg &= ~1;
lastarg = A0 + nargregs - 1;
if (reg > lastarg) {
*regp = reg;
return block(FUNARG, p, NIL, p->n_type, p->n_df, p->n_sue);
}
q = block(REG, NIL, NIL, p->n_type, p->n_df, p->n_sue);
q->n_rval = A0A1 + (reg - A0);
q = buildtree(ASSIGN, q, p);
*regp = reg + 2;
return q;
}
/* setup call stack with 32-bit argument */
/* called from moveargs() */
static NODE *
movearg_32bit(NODE *p, int *regp)
{
int reg = *regp;
NODE *q;
q = block(REG, NIL, NIL, p->n_type, p->n_df, p->n_sue);
q->n_rval = reg++;
q = buildtree(ASSIGN, q, p);
*regp = reg;
return q;
}
static NODE *
moveargs(NODE *p, int *regp)
{
NODE *r, **rp;
int lastreg;
int reg;
if (p->n_op == CM) {
p->n_left = moveargs(p->n_left, regp);
r = p->n_right;
rp = &p->n_right;
} else {
r = p;
rp = &p;
}
lastreg = A0 + nargregs - 1;
reg = *regp;
if (reg > lastreg && r->n_op != STARG)
*rp = block(FUNARG, r, NIL, r->n_type, r->n_df, r->n_sue);
else if (r->n_op == STARG) {
*rp = movearg_struct(r, p, regp);
} else if (DEUNSIGN(r->n_type) == LONGLONG) {
*rp = movearg_64bit(r, regp);
} else if (r->n_type == DOUBLE || r->n_type == LDOUBLE) {
/* XXX bounce in and out of temporary to change to longlong */
NODE *t1 = tempnode(0, LONGLONG, 0, MKSUE(LONGLONG));
int tmpnr = regno(t1);
NODE *t2 = tempnode(tmpnr, r->n_type, r->n_df, r->n_sue);
t1 = movearg_64bit(t1, regp);
r = block(ASSIGN, t2, r, r->n_type, r->n_df, r->n_sue);
if (p->n_op == CM) {
p->n_left = buildtree(CM, p->n_left, t1);
p->n_right = r;
} else {
p = buildtree(CM, t1, r);
}
} else if (r->n_type == FLOAT) {
/* XXX bounce in and out of temporary to change to int */
NODE *t1 = tempnode(0, INT, 0, MKSUE(INT));
int tmpnr = regno(t1);
NODE *t2 = tempnode(tmpnr, r->n_type, r->n_df, r->n_sue);
t1 = movearg_32bit(t1, regp);
r = block(ASSIGN, t2, r, r->n_type, r->n_df, r->n_sue);
if (p->n_op == CM) {
p->n_left = buildtree(CM, p->n_left, t1);
p->n_right = r;
} else {
p = buildtree(CM, t1, r);
}
} else {
*rp = movearg_32bit(r, regp);
}
return p;
}
/*
* Called with a function call with arguments as argument.
* This is done early in buildtree() and only done once.
*/
NODE *
funcode(NODE *p)
{
int regnum = A0;
NODE *l, *r, *t, *q;
int ty;
l = p->n_left;
r = p->n_right;
/*
* if returning a structure, make the first argument
* a hidden pointer to return structure.
*/
ty = DECREF(l->n_type);
if (ty == STRTY+FTN || ty == UNIONTY+FTN) {
ty = DECREF(l->n_type) - FTN;
q = tempnode(0, ty, l->n_df, l->n_sue);
q = buildtree(ADDROF, q, NIL);
if (r->n_op != CM) {
p->n_right = block(CM, q, r, INCREF(ty),
l->n_df, l->n_sue);
} else {
for (t = r; t->n_left->n_op == CM; t = t->n_left)
;
t->n_left = block(CM, q, t->n_left, INCREF(ty),
l->n_df, l->n_sue);
}
}
p->n_right = moveargs(p->n_right, ®num);
return p;
}