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-rw-r--r--src/cmd/5l/noop.c671
1 files changed, 3 insertions, 668 deletions
diff --git a/src/cmd/5l/noop.c b/src/cmd/5l/noop.c
index 305ed684e..d42c86289 100644
--- a/src/cmd/5l/noop.c
+++ b/src/cmd/5l/noop.c
@@ -32,677 +32,12 @@
#include "l.h"
#include "../ld/lib.h"
-#include "../../pkg/runtime/stack.h"
-
-static Sym* sym_div;
-static Sym* sym_divu;
-static Sym* sym_mod;
-static Sym* sym_modu;
-static Sym* symmorestack;
-static Prog* pmorestack;
-
-static Prog* stacksplit(Prog*, int32);
-
-static void
-linkcase(Prog *casep)
-{
- Prog *p;
-
- for(p = casep; p != P; p = p->link){
- if(p->as == ABCASE) {
- for(; p != P && p->as == ABCASE; p = p->link)
- p->pcrel = casep;
- break;
- }
- }
-}
void
noops(void)
{
- Prog *p, *q, *q1, *q2;
- int o;
- Sym *tlsfallback, *gmsym;
-
- /*
- * find leaf subroutines
- * strip NOPs
- * expand RET
- * expand BECOME pseudo
- * fixup TLS
- */
-
- if(debug['v'])
- Bprint(&bso, "%5.2f noops\n", cputime());
- Bflush(&bso);
-
- symmorestack = lookup("runtime.morestack", 0);
- if(symmorestack->type != STEXT) {
- diag("runtime·morestack not defined");
- errorexit();
- }
- pmorestack = symmorestack->text;
- pmorestack->reg |= NOSPLIT;
-
- tlsfallback = lookup("runtime.read_tls_fallback", 0);
- gmsym = S;
- if(linkmode == LinkExternal)
- gmsym = lookup("runtime.tlsgm", 0);
- q = P;
- for(cursym = textp; cursym != nil; cursym = cursym->next) {
- for(p = cursym->text; p != P; p = p->link) {
- switch(p->as) {
- case ACASE:
- if(flag_shared)
- linkcase(p);
- break;
-
- case ATEXT:
- p->mark |= LEAF;
- break;
-
- case ARET:
- break;
-
- case ADIV:
- case ADIVU:
- case AMOD:
- case AMODU:
- q = p;
- if(prog_div == P)
- initdiv();
- cursym->text->mark &= ~LEAF;
- continue;
-
- case ANOP:
- q1 = p->link;
- q->link = q1; /* q is non-nop */
- if(q1 != P)
- q1->mark |= p->mark;
- continue;
-
- case ABL:
- case ABX:
- cursym->text->mark &= ~LEAF;
-
- case ABCASE:
- case AB:
-
- case ABEQ:
- case ABNE:
- case ABCS:
- case ABHS:
- case ABCC:
- case ABLO:
- case ABMI:
- case ABPL:
- case ABVS:
- case ABVC:
- case ABHI:
- case ABLS:
- case ABGE:
- case ABLT:
- case ABGT:
- case ABLE:
- q1 = p->cond;
- if(q1 != P) {
- while(q1->as == ANOP) {
- q1 = q1->link;
- p->cond = q1;
- }
- }
- break;
- case AWORD:
- // Rewrite TLS register fetch: MRC 15, 0, <reg>, C13, C0, 3
- if((p->to.offset & 0xffff0fff) == 0xee1d0f70) {
- if(HEADTYPE == Hopenbsd) {
- p->as = ARET;
- } else if(goarm < 7) {
- if(tlsfallback->type != STEXT) {
- diag("runtime·read_tls_fallback not defined");
- errorexit();
- }
- // BL runtime.read_tls_fallback(SB)
- p->as = ABL;
- p->to.type = D_BRANCH;
- p->to.sym = tlsfallback;
- p->cond = tlsfallback->text;
- p->to.offset = 0;
- cursym->text->mark &= ~LEAF;
- }
- if(linkmode == LinkExternal) {
- // runtime.tlsgm is relocated with R_ARM_TLS_LE32
- // and $runtime.tlsgm will contain the TLS offset.
- //
- // MOV $runtime.tlsgm+tlsoffset(SB), REGTMP
- // ADD REGTMP, <reg>
- //
- // In shared mode, runtime.tlsgm is relocated with
- // R_ARM_TLS_IE32 and runtime.tlsgm(SB) will point
- // to the GOT entry containing the TLS offset.
- //
- // MOV runtime.tlsgm(SB), REGTMP
- // ADD REGTMP, <reg>
- // SUB -tlsoffset, <reg>
- //
- // The SUB compensates for tlsoffset
- // used in runtime.save_gm and runtime.load_gm.
- q = p;
- p = appendp(p);
- p->as = AMOVW;
- p->scond = 14;
- p->reg = NREG;
- if(flag_shared) {
- p->from.type = D_OREG;
- p->from.offset = 0;
- } else {
- p->from.type = D_CONST;
- p->from.offset = tlsoffset;
- }
- p->from.sym = gmsym;
- p->from.name = D_EXTERN;
- p->to.type = D_REG;
- p->to.reg = REGTMP;
- p->to.offset = 0;
-
- p = appendp(p);
- p->as = AADD;
- p->scond = 14;
- p->reg = NREG;
- p->from.type = D_REG;
- p->from.reg = REGTMP;
- p->to.type = D_REG;
- p->to.reg = (q->to.offset & 0xf000) >> 12;
- p->to.offset = 0;
-
- if(flag_shared) {
- p = appendp(p);
- p->as = ASUB;
- p->scond = 14;
- p->reg = NREG;
- p->from.type = D_CONST;
- p->from.offset = -tlsoffset;
- p->to.type = D_REG;
- p->to.reg = (q->to.offset & 0xf000) >> 12;
- p->to.offset = 0;
- }
- }
- }
- }
- q = p;
- }
- }
-
- for(cursym = textp; cursym != nil; cursym = cursym->next) {
- for(p = cursym->text; p != P; p = p->link) {
- o = p->as;
- switch(o) {
- case ATEXT:
- autosize = p->to.offset + 4;
- if(autosize <= 4)
- if(cursym->text->mark & LEAF) {
- p->to.offset = -4;
- autosize = 0;
- }
-
- if(!autosize && !(cursym->text->mark & LEAF)) {
- if(debug['v'])
- Bprint(&bso, "save suppressed in: %s\n",
- cursym->name);
- Bflush(&bso);
- cursym->text->mark |= LEAF;
- }
- if(cursym->text->mark & LEAF) {
- cursym->leaf = 1;
- if(!autosize)
- break;
- }
-
- if(!(p->reg & NOSPLIT))
- p = stacksplit(p, autosize); // emit split check
-
- // MOVW.W R14,$-autosize(SP)
- p = appendp(p);
- p->as = AMOVW;
- p->scond |= C_WBIT;
- p->from.type = D_REG;
- p->from.reg = REGLINK;
- p->to.type = D_OREG;
- p->to.offset = -autosize;
- p->to.reg = REGSP;
- p->spadj = autosize;
-
- if(cursym->text->reg & WRAPPER) {
- // g->panicwrap += autosize;
- // MOVW panicwrap_offset(g), R3
- // ADD $autosize, R3
- // MOVW R3 panicwrap_offset(g)
- p = appendp(p);
- p->as = AMOVW;
- p->from.type = D_OREG;
- p->from.reg = REGG;
- p->from.offset = 2*PtrSize;
- p->to.type = D_REG;
- p->to.reg = 3;
-
- p = appendp(p);
- p->as = AADD;
- p->from.type = D_CONST;
- p->from.offset = autosize;
- p->to.type = D_REG;
- p->to.reg = 3;
-
- p = appendp(p);
- p->as = AMOVW;
- p->from.type = D_REG;
- p->from.reg = 3;
- p->to.type = D_OREG;
- p->to.reg = REGG;
- p->to.offset = 2*PtrSize;
- }
- break;
-
- case ARET:
- nocache(p);
- if(cursym->text->mark & LEAF) {
- if(!autosize) {
- p->as = AB;
- p->from = zprg.from;
- if(p->to.sym) { // retjmp
- p->to.type = D_BRANCH;
- p->cond = p->to.sym->text;
- } else {
- p->to.type = D_OREG;
- p->to.offset = 0;
- p->to.reg = REGLINK;
- }
- break;
- }
- }
-
- if(cursym->text->reg & WRAPPER) {
- int cond;
-
- // Preserve original RET's cond, to allow RET.EQ
- // in the implementation of reflect.call.
- cond = p->scond;
- p->scond = C_SCOND_NONE;
-
- // g->panicwrap -= autosize;
- // MOVW panicwrap_offset(g), R3
- // SUB $autosize, R3
- // MOVW R3 panicwrap_offset(g)
- p->as = AMOVW;
- p->from.type = D_OREG;
- p->from.reg = REGG;
- p->from.offset = 2*PtrSize;
- p->to.type = D_REG;
- p->to.reg = 3;
- p = appendp(p);
-
- p->as = ASUB;
- p->from.type = D_CONST;
- p->from.offset = autosize;
- p->to.type = D_REG;
- p->to.reg = 3;
- p = appendp(p);
-
- p->as = AMOVW;
- p->from.type = D_REG;
- p->from.reg = 3;
- p->to.type = D_OREG;
- p->to.reg = REGG;
- p->to.offset = 2*PtrSize;
- p = appendp(p);
-
- p->scond = cond;
- }
-
- p->as = AMOVW;
- p->scond |= C_PBIT;
- p->from.type = D_OREG;
- p->from.offset = autosize;
- p->from.reg = REGSP;
- p->to.type = D_REG;
- p->to.reg = REGPC;
- // If there are instructions following
- // this ARET, they come from a branch
- // with the same stackframe, so no spadj.
-
- if(p->to.sym) { // retjmp
- p->to.reg = REGLINK;
- q2 = appendp(p);
- q2->as = AB;
- q2->to.type = D_BRANCH;
- q2->to.sym = p->to.sym;
- q2->cond = p->to.sym->text;
- p->to.sym = nil;
- p = q2;
- }
- break;
-
- case AADD:
- if(p->from.type == D_CONST && p->from.reg == NREG && p->to.type == D_REG && p->to.reg == REGSP)
- p->spadj = -p->from.offset;
- break;
-
- case ASUB:
- if(p->from.type == D_CONST && p->from.reg == NREG && p->to.type == D_REG && p->to.reg == REGSP)
- p->spadj = p->from.offset;
- break;
-
- case ADIV:
- case ADIVU:
- case AMOD:
- case AMODU:
- if(debug['M'])
- break;
- if(p->from.type != D_REG)
- break;
- if(p->to.type != D_REG)
- break;
- q1 = p;
-
- /* MOV a,4(SP) */
- p = appendp(p);
- 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 */
- p = appendp(p);
- 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 */
- p = appendp(p);
- p->as = ABL;
- p->line = q1->line;
- p->to.type = D_BRANCH;
- p->cond = p;
- switch(o) {
- case ADIV:
- p->cond = prog_div;
- p->to.sym = sym_div;
- break;
- case ADIVU:
- p->cond = prog_divu;
- p->to.sym = sym_divu;
- break;
- case AMOD:
- p->cond = prog_mod;
- p->to.sym = sym_mod;
- break;
- case AMODU:
- p->cond = prog_modu;
- p->to.sym = sym_modu;
- break;
- }
+ LSym *s;
- /* MOV REGTMP, b */
- p = appendp(p);
- 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 */
- p = appendp(p);
- p->as = AADD;
- p->line = q1->line;
- 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;
- p->spadj = -8;
-
- /* Keep saved LR at 0(SP) after SP change. */
- /* MOVW 0(SP), REGTMP; MOVW REGTMP, -8!(SP) */
- /* TODO: Remove SP adjustments; see issue 6699. */
- q1->as = AMOVW;
- q1->from.type = D_OREG;
- q1->from.reg = REGSP;
- q1->from.offset = 0;
- q1->reg = NREG;
- q1->to.type = D_REG;
- q1->to.reg = REGTMP;
-
- /* SUB $8,SP */
- q1 = appendp(q1);
- q1->as = AMOVW;
- q1->from.type = D_REG;
- q1->from.reg = REGTMP;
- q1->reg = NREG;
- q1->to.type = D_OREG;
- q1->to.reg = REGSP;
- q1->to.offset = -8;
- q1->scond |= C_WBIT;
- q1->spadj = 8;
-
- break;
- case AMOVW:
- if((p->scond & C_WBIT) && p->to.type == D_OREG && p->to.reg == REGSP)
- p->spadj = -p->to.offset;
- if((p->scond & C_PBIT) && p->from.type == D_OREG && p->from.reg == REGSP && p->to.reg != REGPC)
- p->spadj = -p->from.offset;
- if(p->from.type == D_CONST && p->from.reg == REGSP && p->to.type == D_REG && p->to.reg == REGSP)
- p->spadj = -p->from.offset;
- break;
- }
- }
- }
-}
-
-static Prog*
-stacksplit(Prog *p, int32 framesize)
-{
- int32 arg;
-
- // MOVW g_stackguard(g), R1
- p = appendp(p);
- p->as = AMOVW;
- p->from.type = D_OREG;
- p->from.reg = REGG;
- p->to.type = D_REG;
- p->to.reg = 1;
-
- if(framesize <= StackSmall) {
- // small stack: SP < stackguard
- // CMP stackguard, SP
- p = appendp(p);
- p->as = ACMP;
- p->from.type = D_REG;
- p->from.reg = 1;
- p->reg = REGSP;
- } else if(framesize <= StackBig) {
- // large stack: SP-framesize < stackguard-StackSmall
- // MOVW $-framesize(SP), R2
- // CMP stackguard, R2
- p = appendp(p);
- p->as = AMOVW;
- p->from.type = D_CONST;
- p->from.reg = REGSP;
- p->from.offset = -framesize;
- p->to.type = D_REG;
- p->to.reg = 2;
-
- p = appendp(p);
- p->as = ACMP;
- p->from.type = D_REG;
- p->from.reg = 1;
- p->reg = 2;
- } else {
- // Such a large stack we need to protect against wraparound
- // if SP is close to zero.
- // SP-stackguard+StackGuard < framesize + (StackGuard-StackSmall)
- // The +StackGuard on both sides is required to keep the left side positive:
- // SP is allowed to be slightly below stackguard. See stack.h.
- // CMP $StackPreempt, R1
- // MOVW.NE $StackGuard(SP), R2
- // SUB.NE R1, R2
- // MOVW.NE $(framesize+(StackGuard-StackSmall)), R3
- // CMP.NE R3, R2
- p = appendp(p);
- p->as = ACMP;
- p->from.type = D_CONST;
- p->from.offset = (uint32)StackPreempt;
- p->reg = 1;
-
- p = appendp(p);
- p->as = AMOVW;
- p->from.type = D_CONST;
- p->from.reg = REGSP;
- p->from.offset = StackGuard;
- p->to.type = D_REG;
- p->to.reg = 2;
- p->scond = C_SCOND_NE;
-
- p = appendp(p);
- p->as = ASUB;
- p->from.type = D_REG;
- p->from.reg = 1;
- p->to.type = D_REG;
- p->to.reg = 2;
- p->scond = C_SCOND_NE;
-
- p = appendp(p);
- p->as = AMOVW;
- p->from.type = D_CONST;
- p->from.offset = framesize + (StackGuard - StackSmall);
- p->to.type = D_REG;
- p->to.reg = 3;
- p->scond = C_SCOND_NE;
-
- p = appendp(p);
- p->as = ACMP;
- p->from.type = D_REG;
- p->from.reg = 3;
- p->reg = 2;
- p->scond = C_SCOND_NE;
- }
-
- // MOVW.LS $framesize, R1
- p = appendp(p);
- p->as = AMOVW;
- p->scond = C_SCOND_LS;
- p->from.type = D_CONST;
- p->from.offset = framesize;
- p->to.type = D_REG;
- p->to.reg = 1;
-
- // MOVW.LS $args, R2
- p = appendp(p);
- p->as = AMOVW;
- p->scond = C_SCOND_LS;
- p->from.type = D_CONST;
- arg = cursym->text->to.offset2;
- if(arg == 1) // special marker for known 0
- arg = 0;
- if(arg&3)
- diag("misaligned argument size in stack split");
- p->from.offset = arg;
- p->to.type = D_REG;
- p->to.reg = 2;
-
- // MOVW.LS R14, R3
- p = appendp(p);
- p->as = AMOVW;
- p->scond = C_SCOND_LS;
- p->from.type = D_REG;
- p->from.reg = REGLINK;
- p->to.type = D_REG;
- p->to.reg = 3;
-
- // BL.LS runtime.morestack(SB) // modifies LR, returns with LO still asserted
- p = appendp(p);
- p->as = ABL;
- p->scond = C_SCOND_LS;
- p->to.type = D_BRANCH;
- p->to.sym = symmorestack;
- p->cond = pmorestack;
-
- // BLS start
- p = appendp(p);
- p->as = ABLS;
- p->to.type = D_BRANCH;
- p->cond = cursym->text->link;
-
- return p;
-}
-
-static void
-sigdiv(char *n)
-{
- Sym *s;
-
- s = lookup(n, 0);
- if(s->type == STEXT)
- if(s->sig == 0)
- s->sig = SIGNINTERN;
-}
-
-void
-divsig(void)
-{
- sigdiv("_div");
- sigdiv("_divu");
- sigdiv("_mod");
- sigdiv("_modu");
-}
-
-void
-initdiv(void)
-{
- Sym *s2, *s3, *s4, *s5;
-
- if(prog_div != P)
- return;
- sym_div = s2 = lookup("_div", 0);
- sym_divu = s3 = lookup("_divu", 0);
- sym_mod = s4 = lookup("_mod", 0);
- sym_modu = s5 = lookup("_modu", 0);
- prog_div = s2->text;
- prog_divu = s3->text;
- prog_mod = s4->text;
- prog_modu = s5->text;
- if(prog_div == P) {
- diag("undefined: %s", s2->name);
- prog_div = cursym->text;
- }
- if(prog_divu == P) {
- diag("undefined: %s", s3->name);
- prog_divu = cursym->text;
- }
- if(prog_mod == P) {
- diag("undefined: %s", s4->name);
- prog_mod = cursym->text;
- }
- if(prog_modu == P) {
- diag("undefined: %s", s5->name);
- prog_modu = cursym->text;
- }
-}
-
-void
-nocache(Prog *p)
-{
- p->optab = 0;
- p->from.class = 0;
- p->to.class = 0;
+ for(s = ctxt->textp; s != nil; s = s->next)
+ ctxt->arch->addstacksplit(ctxt, s);
}
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