ref: 1132d1b9df4c9ea2b857fa9778fe6762cd81ded8
dir: /sys/src/cmd/kl/noop.c/
#include "l.h"
void
noops(void)
{
Prog *p, *p1, *q, *q1;
int o, curframe, curbecome, maxbecome;
/*
* find leaf subroutines
* become sizes
* frame sizes
* strip NOPs
* expand RET
* expand BECOME pseudo
*/
if(debug['v'])
Bprint(&bso, "%5.2f noops\n", cputime());
Bflush(&bso);
curframe = 0;
curbecome = 0;
maxbecome = 0;
curtext = 0;
q = P;
for(p = firstp; p != P; p = p->link) {
/* find out how much arg space is used in this TEXT */
if(p->to.type == D_OREG && p->to.reg == REGSP)
if(p->to.offset > curframe)
curframe = p->to.offset;
switch(p->as) {
/* too hard, just leave alone */
case ATEXT:
if(curtext && curtext->from.sym) {
curtext->from.sym->frame = curframe;
curtext->from.sym->become = curbecome;
if(curbecome > maxbecome)
maxbecome = curbecome;
}
curframe = 0;
curbecome = 0;
q = p;
p->mark |= LABEL|LEAF|SYNC;
if(p->link)
p->link->mark |= LABEL;
curtext = p;
break;
case AORN:
q = p;
if(p->to.type == D_REG)
if(p->to.reg == REGZERO)
p->mark |= LABEL|SYNC;
break;
case AUNIMP:
case ATAS:
case ASWAP:
case ATA:
case ATCC:
case ATCS:
case ATE:
case ATG:
case ATGE:
case ATGU:
case ATL:
case ATLE:
case ATLEU:
case ATN:
case ATNE:
case ATNEG:
case ATPOS:
case ATVC:
case ATVS:
case AWORD:
q = p;
p->mark |= LABEL|SYNC;
continue;
case AFABSD:
case AFABSF:
case AFABSX:
case AFADDD:
case AFADDF:
case AFADDX:
case AFDIVD:
case AFDIVF:
case AFDIVX:
case AFMOVD:
case AFMOVDF:
case AFMOVDW:
case AFMOVDX:
case AFMOVF:
case AFMOVFD:
case AFMOVFW:
case AFMOVFX:
case AFMOVWD:
case AFMOVWF:
case AFMOVWX:
case AFMOVX:
case AFMOVXD:
case AFMOVXF:
case AFMOVXW:
case AFMULD:
case AFMULF:
case AFMULX:
case AFNEGD:
case AFNEGF:
case AFNEGX:
case AFSQRTD:
case AFSQRTF:
case AFSQRTX:
case AFSUBD:
case AFSUBF:
case AFSUBX:
q = p;
p->mark |= FLOAT;
continue;
case AMUL:
case ADIV:
case ADIVL:
case AMOD:
case AMODL:
q = p;
if(!debug['M']) {
if(prog_mul == P)
initmuldiv();
if(curtext != P)
curtext->mark &= ~LEAF;
}
continue;
case AJMPL:
if(curtext != P)
curtext->mark &= ~LEAF;
case AJMP:
case ABA:
case ABN:
case ABE:
case ABNE:
case ABLE:
case ABG:
case ABL:
case ABGE:
case ABLEU:
case ABGU:
case ABCS:
case ABCC:
case ABNEG:
case ABPOS:
case ABVC:
case ABVS:
case AFBN:
case AFBO:
case AFBE:
case AFBLG:
case AFBG:
case AFBLE:
case AFBGE:
case AFBL:
case AFBNE:
case AFBUE:
case AFBA:
case AFBU:
case AFBUG:
case AFBULE:
case AFBUGE:
case AFBUL:
p->mark |= BRANCH;
q = p;
q1 = p->cond;
if(q1 != P) {
while(q1->as == ANOP) {
q1 = q1->link;
p->cond = q1;
}
if(!(q1->mark & LEAF))
q1->mark |= LABEL;
} else
p->mark |= LABEL;
q1 = p->link;
if(q1 != P)
q1->mark |= LABEL;
continue;
case AFCMPD:
case AFCMPED:
case AFCMPEF:
case AFCMPEX:
case AFCMPF:
case AFCMPX:
q = p;
p->mark |= FCMP|FLOAT;
continue;
case ARETURN:
/* special form of RETURN is BECOME */
if(p->from.type == D_CONST)
if(p->from.offset > curbecome)
curbecome = p->from.offset;
q = p;
if(p->link != P)
p->link->mark |= LABEL;
continue;
case ANOP:
q1 = p->link;
q->link = q1; /* q is non-nop */
q1->mark |= p->mark;
continue;
default:
q = p;
continue;
}
}
if(curtext && curtext->from.sym) {
curtext->from.sym->frame = curframe;
curtext->from.sym->become = curbecome;
if(curbecome > maxbecome)
maxbecome = curbecome;
}
if(debug['b'])
print("max become = %d\n", maxbecome);
xdefine("ALEFbecome", STEXT, maxbecome);
curtext = 0;
for(p = firstp; p != P; p = p->link) {
switch(p->as) {
case ATEXT:
curtext = p;
break;
case AJMPL:
if(curtext != P && curtext->from.sym != S && curtext->to.offset >= 0) {
o = maxbecome - curtext->from.sym->frame;
if(o <= 0)
break;
/* calling a become or calling a variable */
if(p->to.sym == S || p->to.sym->become) {
curtext->to.offset += o;
if(debug['b']) {
curp = p;
print("%D calling %D increase %d\n",
&curtext->from, &p->to, o);
}
}
}
break;
}
}
curtext = P;
for(p = firstp; p != P; p = p->link) {
o = p->as;
switch(o) {
case ATEXT:
curtext = p;
autosize = p->to.offset + 4;
if((p->mark & LEAF) && autosize <= 4)
autosize = 0;
else
if(autosize & 4)
autosize += 4;
p->to.offset = autosize - 4;
q = p;
if(autosize) {
q = prg();
q->as = ASUB;
q->line = p->line;
q->from.type = D_CONST;
q->from.offset = autosize;
q->to.type = D_REG;
q->to.reg = REGSP;
q->link = p->link;
p->link = q;
} else
if(!(curtext->mark & LEAF)) {
if(debug['v'])
Bprint(&bso, "save suppressed in: %s\n",
curtext->from.sym->name);
curtext->mark |= LEAF;
}
if(curtext->mark & LEAF) {
if(curtext->from.sym)
curtext->from.sym->type = SLEAF;
break;
}
q1 = prg();
q1->as = AMOVW;
q1->line = p->line;
q1->from.type = D_REG;
q1->from.reg = REGLINK;
q1->to.type = D_OREG;
q1->from.offset = 0;
q1->to.reg = REGSP;
q1->link = q->link;
q->link = q1;
break;
case AMUL:
case ADIV:
case ADIVL:
case AMOD:
case AMODL:
if(debug['M'])
break;
if(p->from.type != D_REG)
break;
if(p->to.type != D_REG)
break;
q1 = p;
/* MOV a,4(SP) */
q = prg();
q->link = p->link;
p->link = q;
p = q;
p->as = AMOVW;
p->line = q1->line;
p->from.type = D_REG;
p->from.reg = q1->from.reg;
p->to.type = D_OREG;
p->to.reg = REGSP;
p->to.offset = 4;
/* MOV b,REGTMP */
q = prg();
q->link = p->link;
p->link = q;
p = q;
p->as = AMOVW;
p->line = q1->line;
p->from.type = D_REG;
p->from.reg = q1->reg;
if(q1->reg == NREG)
p->from.reg = q1->to.reg;
p->to.type = D_REG;
p->to.reg = REGTMP;
p->to.offset = 0;
/* CALL appropriate */
q = prg();
q->link = p->link;
p->link = q;
p = q;
p->as = AJMPL;
p->line = q1->line;
p->to.type = D_BRANCH;
p->cond = p;
p->mark |= BRANCH;
switch(o) {
case AMUL:
p->cond = prog_mul;
break;
case ADIV:
p->cond = prog_div;
break;
case ADIVL:
p->cond = prog_divl;
break;
case AMOD:
p->cond = prog_mod;
break;
case AMODL:
p->cond = prog_modl;
break;
}
/* MOV REGTMP, b */
q = prg();
q->link = p->link;
p->link = q;
p = q;
p->as = AMOVW;
p->line = q1->line;
p->from.type = D_REG;
p->from.reg = REGTMP;
p->from.offset = 0;
p->to.type = D_REG;
p->to.reg = q1->to.reg;
/* ADD $8,SP */
q = prg();
q->link = p->link;
p->link = q;
p = q;
p->as = AADD;
p->from.type = D_CONST;
p->from.reg = NREG;
p->from.offset = 8;
p->reg = NREG;
p->to.type = D_REG;
p->to.reg = REGSP;
/* SUB $8,SP */
q1->as = ASUB;
q1->from.type = D_CONST;
q1->from.offset = 8;
q1->from.reg = NREG;
q1->reg = NREG;
q1->to.type = D_REG;
q1->to.reg = REGSP;
break;
case ARETURN:
if(p->from.type == D_CONST)
goto become;
if(curtext->mark & LEAF) {
if(!autosize) {
p->as = AJMP;
p->from = zprg.from;
p->to.type = D_OREG;
p->to.offset = 8;
p->to.reg = REGLINK;
p->mark |= BRANCH;
break;
}
p->as = AADD;
p->from.type = D_CONST;
p->from.offset = autosize;
p->to.type = D_REG;
p->to.reg = REGSP;
q = prg();
q->as = AJMP;
q->line = p->line;
q->to.type = D_OREG;
q->to.offset = 8;
q->to.reg = REGLINK;
q->mark |= BRANCH;
q->link = p->link;
p->link = q;
break;
}
p->as = AMOVW;
p->from.type = D_OREG;
p->from.offset = 0;
p->from.reg = REGSP;
p->to.type = D_REG;
p->to.reg = REGRET+1;
q = p;
if(autosize) {
q = prg();
q->as = AADD;
q->line = p->line;
q->from.type = D_CONST;
q->from.offset = autosize;
q->to.type = D_REG;
q->to.reg = REGSP;
q->link = p->link;
p->link = q;
}
q1 = prg();
q1->as = AJMP;
q1->line = p->line;
q1->to.type = D_OREG;
q1->to.offset = 8;
q1->to.reg = REGRET+1;
q1->mark |= BRANCH;
q1->link = q->link;
q->link = q1;
break;
become:
if(curtext->mark & LEAF) {
q = prg();
q->line = p->line;
q->as = AJMP;
q->from = zprg.from;
q->to = p->to;
q->cond = p->cond;
q->link = p->link;
q->mark |= BRANCH;
p->link = q;
p->as = AADD;
p->from = zprg.from;
p->from.type = D_CONST;
p->from.offset = autosize;
p->to = zprg.to;
p->to.type = D_REG;
p->to.reg = REGSP;
break;
}
q = prg();
q->line = p->line;
q->as = AJMP;
q->from = zprg.from;
q->to = p->to;
q->cond = p->cond;
q->mark |= BRANCH;
q->link = p->link;
p->link = q;
q = prg();
q->line = p->line;
q->as = AADD;
q->from.type = D_CONST;
q->from.offset = autosize;
q->to.type = D_REG;
q->to.reg = REGSP;
q->link = p->link;
p->link = q;
p->as = AMOVW;
p->from = zprg.from;
p->from.type = D_OREG;
p->from.offset = 0;
p->from.reg = REGSP;
p->to = zprg.to;
p->to.type = D_REG;
p->to.reg = REGLINK;
break;
}
}
curtext = P;
q = P; /* p - 1 */
q1 = firstp; /* top of block */
o = 0; /* count of instructions */
for(p = firstp; p != P; p = p1) {
p1 = p->link;
o++;
if(p->mark & NOSCHED){
if(q1 != p){
sched(q1, q);
}
for(; p != P; p = p->link){
if(!(p->mark & NOSCHED))
break;
q = p;
}
p1 = p;
q1 = p;
o = 0;
continue;
}
if(p->mark & (LABEL|SYNC)) {
if(q1 != p)
sched(q1, q);
q1 = p;
o = 1;
}
if(p->mark & (BRANCH|SYNC)) {
sched(q1, p);
q1 = p1;
o = 0;
}
if(o >= NSCHED) {
sched(q1, p);
q1 = p1;
o = 0;
}
q = p;
}
}
void
addnop(Prog *p)
{
Prog *q;
q = prg();
q->as = AORN;
q->line = p->line;
q->from.type = D_REG;
q->from.reg = REGZERO;
q->to.type = D_REG;
q->to.reg = REGZERO;
q->link = p->link;
p->link = q;
}
void
initmuldiv(void)
{
Sym *s1, *s2, *s3, *s4, *s5;
Prog *p;
s1 = lookup("_mul", 0);
s2 = lookup("_div", 0);
s3 = lookup("_divl", 0);
s4 = lookup("_mod", 0);
s5 = lookup("_modl", 0);
for(p = firstp; p != P; p = p->link)
if(p->as == ATEXT) {
if(p->from.sym == s1)
prog_mul = p;
if(p->from.sym == s2)
prog_div = p;
if(p->from.sym == s3)
prog_divl = p;
if(p->from.sym == s4)
prog_mod = p;
if(p->from.sym == s5)
prog_modl = p;
}
if(prog_mul == P) {
diag("undefined: %s", s1->name);
prog_mul = curtext;
}
if(prog_div == P) {
diag("undefined: %s", s2->name);
prog_div = curtext;
}
if(prog_divl == P) {
diag("undefined: %s", s3->name);
prog_divl = curtext;
}
if(prog_mod == P) {
diag("undefined: %s", s4->name);
prog_mod = curtext;
}
if(prog_modl == P) {
diag("undefined: %s", s5->name);
prog_modl = curtext;
}
}