ref: b0a059537147237e868b4a8f07922ae8a349e55c
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; } }