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-rw-r--r--src/cmd/6g/cgen.c1299
1 files changed, 1299 insertions, 0 deletions
diff --git a/src/cmd/6g/cgen.c b/src/cmd/6g/cgen.c
new file mode 100644
index 000000000..24f88a416
--- /dev/null
+++ b/src/cmd/6g/cgen.c
@@ -0,0 +1,1299 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "gg.h"
+
+/*
+ * generate:
+ * res = n;
+ * simplifies and calls gmove.
+ */
+void
+cgen(Node *n, Node *res)
+{
+ Node *nl, *nr, *r;
+ Node n1, n2;
+ int a, f;
+ Prog *p1, *p2, *p3;
+ Addr addr;
+
+ if(debug['g']) {
+ dump("\ncgen-n", n);
+ dump("cgen-res", res);
+ }
+ if(n == N || n->type == T)
+ goto ret;
+
+ if(res == N || res->type == T)
+ fatal("cgen: res nil");
+
+ while(n->op == OCONVNOP)
+ n = n->left;
+
+ // inline slices
+ if(cgen_inline(n, res))
+ goto ret;
+
+ if(n->ullman >= UINF) {
+ if(n->op == OINDREG)
+ fatal("cgen: this is going to misscompile");
+ if(res->ullman >= UINF) {
+ tempname(&n1, n->type);
+ cgen(n, &n1);
+ cgen(&n1, res);
+ goto ret;
+ }
+ }
+
+ if(isfat(n->type)) {
+ if(n->type->width < 0)
+ fatal("forgot to compute width for %T", n->type);
+ sgen(n, res, n->type->width);
+ goto ret;
+ }
+
+ if(!res->addable) {
+ if(n->ullman > res->ullman) {
+ regalloc(&n1, n->type, res);
+ cgen(n, &n1);
+ if(n1.ullman > res->ullman) {
+ dump("n1", &n1);
+ dump("res", res);
+ fatal("loop in cgen");
+ }
+ cgen(&n1, res);
+ regfree(&n1);
+ goto ret;
+ }
+
+ if(res->ullman >= UINF)
+ goto gen;
+
+ if(complexop(n, res)) {
+ complexgen(n, res);
+ goto ret;
+ }
+
+ f = 1; // gen thru register
+ switch(n->op) {
+ case OLITERAL:
+ if(smallintconst(n))
+ f = 0;
+ break;
+ case OREGISTER:
+ f = 0;
+ break;
+ }
+
+ if(!iscomplex[n->type->etype]) {
+ a = optoas(OAS, res->type);
+ if(sudoaddable(a, res, &addr)) {
+ if(f) {
+ regalloc(&n2, res->type, N);
+ cgen(n, &n2);
+ p1 = gins(a, &n2, N);
+ regfree(&n2);
+ } else
+ p1 = gins(a, n, N);
+ p1->to = addr;
+ if(debug['g'])
+ print("%P [ignore previous line]\n", p1);
+ sudoclean();
+ goto ret;
+ }
+ }
+
+ gen:
+ igen(res, &n1, N);
+ cgen(n, &n1);
+ regfree(&n1);
+ goto ret;
+ }
+
+ // update addressability for string, slice
+ // can't do in walk because n->left->addable
+ // changes if n->left is an escaping local variable.
+ switch(n->op) {
+ case OLEN:
+ if(isslice(n->left->type) || istype(n->left->type, TSTRING))
+ n->addable = n->left->addable;
+ break;
+ case OCAP:
+ if(isslice(n->left->type))
+ n->addable = n->left->addable;
+ break;
+ }
+
+ if(complexop(n, res)) {
+ complexgen(n, res);
+ goto ret;
+ }
+
+ if(n->addable) {
+ gmove(n, res);
+ goto ret;
+ }
+
+ nl = n->left;
+ nr = n->right;
+
+ if(nl != N && nl->ullman >= UINF)
+ if(nr != N && nr->ullman >= UINF) {
+ tempname(&n1, nl->type);
+ cgen(nl, &n1);
+ n2 = *n;
+ n2.left = &n1;
+ cgen(&n2, res);
+ goto ret;
+ }
+
+ if(!iscomplex[n->type->etype]) {
+ a = optoas(OAS, n->type);
+ if(sudoaddable(a, n, &addr)) {
+ if(res->op == OREGISTER) {
+ p1 = gins(a, N, res);
+ p1->from = addr;
+ } else {
+ regalloc(&n2, n->type, N);
+ p1 = gins(a, N, &n2);
+ p1->from = addr;
+ gins(a, &n2, res);
+ regfree(&n2);
+ }
+ sudoclean();
+ goto ret;
+ }
+ }
+
+ switch(n->op) {
+ default:
+ dump("cgen", n);
+ fatal("cgen: unknown op %N", n);
+ break;
+
+ // these call bgen to get a bool value
+ case OOROR:
+ case OANDAND:
+ case OEQ:
+ case ONE:
+ case OLT:
+ case OLE:
+ case OGE:
+ case OGT:
+ case ONOT:
+ p1 = gbranch(AJMP, T);
+ p2 = pc;
+ gmove(nodbool(1), res);
+ p3 = gbranch(AJMP, T);
+ patch(p1, pc);
+ bgen(n, 1, p2);
+ gmove(nodbool(0), res);
+ patch(p3, pc);
+ goto ret;
+
+ case OPLUS:
+ cgen(nl, res);
+ goto ret;
+
+ // unary
+ case OCOM:
+ a = optoas(OXOR, nl->type);
+ regalloc(&n1, nl->type, N);
+ cgen(nl, &n1);
+ nodconst(&n2, nl->type, -1);
+ gins(a, &n2, &n1);
+ gmove(&n1, res);
+ regfree(&n1);
+ goto ret;
+
+ case OMINUS:
+ if(isfloat[nl->type->etype]) {
+ nr = nodintconst(-1);
+ convlit(&nr, n->type);
+ a = optoas(OMUL, nl->type);
+ goto sbop;
+ }
+ a = optoas(n->op, nl->type);
+ goto uop;
+
+ // symmetric binary
+ case OAND:
+ case OOR:
+ case OXOR:
+ case OADD:
+ case OMUL:
+ a = optoas(n->op, nl->type);
+ if(a != AIMULB)
+ goto sbop;
+ cgen_bmul(n->op, nl, nr, res);
+ break;
+
+ // asymmetric binary
+ case OSUB:
+ a = optoas(n->op, nl->type);
+ goto abop;
+
+ case OCONV:
+ regalloc(&n1, nl->type, res);
+ regalloc(&n2, n->type, &n1);
+ cgen(nl, &n1);
+
+ // if we do the conversion n1 -> n2 here
+ // reusing the register, then gmove won't
+ // have to allocate its own register.
+ gmove(&n1, &n2);
+ gmove(&n2, res);
+ regfree(&n2);
+ regfree(&n1);
+ break;
+
+ case ODOT:
+ case ODOTPTR:
+ case OINDEX:
+ case OIND:
+ case ONAME: // PHEAP or PPARAMREF var
+ igen(n, &n1, res);
+ gmove(&n1, res);
+ regfree(&n1);
+ break;
+
+ case OLEN:
+ if(istype(nl->type, TMAP) || istype(nl->type, TCHAN)) {
+ // map and chan have len in the first 32-bit word.
+ // a zero pointer means zero length
+ regalloc(&n1, types[tptr], res);
+ cgen(nl, &n1);
+
+ nodconst(&n2, types[tptr], 0);
+ gins(optoas(OCMP, types[tptr]), &n1, &n2);
+ p1 = gbranch(optoas(OEQ, types[tptr]), T);
+
+ n2 = n1;
+ n2.op = OINDREG;
+ n2.type = types[TINT32];
+ gmove(&n2, &n1);
+
+ patch(p1, pc);
+
+ gmove(&n1, res);
+ regfree(&n1);
+ break;
+ }
+ if(istype(nl->type, TSTRING) || isslice(nl->type)) {
+ // both slice and string have len one pointer into the struct.
+ // a zero pointer means zero length
+ igen(nl, &n1, res);
+ n1.type = types[TUINT32];
+ n1.xoffset += Array_nel;
+ gmove(&n1, res);
+ regfree(&n1);
+ break;
+ }
+ fatal("cgen: OLEN: unknown type %lT", nl->type);
+ break;
+
+ case OCAP:
+ if(istype(nl->type, TCHAN)) {
+ // chan has cap in the second 32-bit word.
+ // a zero pointer means zero length
+ regalloc(&n1, types[tptr], res);
+ cgen(nl, &n1);
+
+ nodconst(&n2, types[tptr], 0);
+ gins(optoas(OCMP, types[tptr]), &n1, &n2);
+ p1 = gbranch(optoas(OEQ, types[tptr]), T);
+
+ n2 = n1;
+ n2.op = OINDREG;
+ n2.xoffset = 4;
+ n2.type = types[TINT32];
+ gmove(&n2, &n1);
+
+ patch(p1, pc);
+
+ gmove(&n1, res);
+ regfree(&n1);
+ break;
+ }
+ if(isslice(nl->type)) {
+ igen(nl, &n1, res);
+ n1.type = types[TUINT32];
+ n1.xoffset += Array_cap;
+ gmove(&n1, res);
+ regfree(&n1);
+ break;
+ }
+ fatal("cgen: OCAP: unknown type %lT", nl->type);
+ break;
+
+ case OADDR:
+ agen(nl, res);
+ break;
+
+ case OCALLMETH:
+ cgen_callmeth(n, 0);
+ cgen_callret(n, res);
+ break;
+
+ case OCALLINTER:
+ cgen_callinter(n, res, 0);
+ cgen_callret(n, res);
+ break;
+
+ case OCALLFUNC:
+ cgen_call(n, 0);
+ cgen_callret(n, res);
+ break;
+
+ case OMOD:
+ case ODIV:
+ if(isfloat[n->type->etype]) {
+ a = optoas(n->op, nl->type);
+ goto abop;
+ }
+ cgen_div(n->op, nl, nr, res);
+ break;
+
+ case OLSH:
+ case ORSH:
+ cgen_shift(n->op, nl, nr, res);
+ break;
+ }
+ goto ret;
+
+sbop: // symmetric binary
+ if(nl->ullman < nr->ullman) {
+ r = nl;
+ nl = nr;
+ nr = r;
+ }
+
+abop: // asymmetric binary
+ if(nl->ullman >= nr->ullman) {
+ regalloc(&n1, nl->type, res);
+ cgen(nl, &n1);
+
+ if(sudoaddable(a, nr, &addr)) {
+ p1 = gins(a, N, &n1);
+ p1->from = addr;
+ gmove(&n1, res);
+ sudoclean();
+ regfree(&n1);
+ goto ret;
+ }
+ regalloc(&n2, nr->type, N);
+ cgen(nr, &n2);
+ } else {
+ regalloc(&n2, nr->type, N);
+ cgen(nr, &n2);
+ regalloc(&n1, nl->type, res);
+ cgen(nl, &n1);
+ }
+ gins(a, &n2, &n1);
+ gmove(&n1, res);
+ regfree(&n1);
+ regfree(&n2);
+ goto ret;
+
+uop: // unary
+ regalloc(&n1, nl->type, res);
+ cgen(nl, &n1);
+ gins(a, N, &n1);
+ gmove(&n1, res);
+ regfree(&n1);
+ goto ret;
+
+ret:
+ ;
+}
+
+/*
+ * generate:
+ * res = &n;
+ */
+void
+agen(Node *n, Node *res)
+{
+ Node *nl, *nr;
+ Node n1, n2, n3, tmp, n4, n5;
+ Prog *p1;
+ uint32 w;
+ uint64 v;
+ Type *t;
+
+ if(debug['g']) {
+ dump("\nagen-res", res);
+ dump("agen-r", n);
+ }
+ if(n == N || n->type == T)
+ return;
+
+ while(n->op == OCONVNOP)
+ n = n->left;
+
+ if(n->addable) {
+ regalloc(&n1, types[tptr], res);
+ gins(ALEAQ, n, &n1);
+ gmove(&n1, res);
+ regfree(&n1);
+ goto ret;
+ }
+
+ nl = n->left;
+ nr = n->right;
+
+ switch(n->op) {
+ default:
+ fatal("agen: unknown op %N", n);
+ break;
+
+ case OCALLMETH:
+ cgen_callmeth(n, 0);
+ cgen_aret(n, res);
+ break;
+
+ case OCALLINTER:
+ cgen_callinter(n, res, 0);
+ cgen_aret(n, res);
+ break;
+
+ case OCALLFUNC:
+ cgen_call(n, 0);
+ cgen_aret(n, res);
+ break;
+
+ case OINDEX:
+ w = n->type->width;
+ if(nr->addable)
+ goto irad;
+ if(nl->addable) {
+ if(!isconst(nr, CTINT)) {
+ regalloc(&n1, nr->type, N);
+ cgen(nr, &n1);
+ }
+ if(!isconst(nl, CTSTR)) {
+ regalloc(&n3, types[tptr], res);
+ agen(nl, &n3);
+ }
+ goto index;
+ }
+ tempname(&tmp, nr->type);
+ cgen(nr, &tmp);
+ nr = &tmp;
+
+ irad:
+ if(!isconst(nl, CTSTR)) {
+ regalloc(&n3, types[tptr], res);
+ agen(nl, &n3);
+ }
+ if(!isconst(nr, CTINT)) {
+ regalloc(&n1, nr->type, N);
+ cgen(nr, &n1);
+ }
+ goto index;
+
+ index:
+ // &a is in &n3 (allocated in res)
+ // i is in &n1 (if not constant)
+ // w is width
+
+ // explicit check for nil if array is large enough
+ // that we might derive too big a pointer.
+ if(isfixedarray(nl->type) && nl->type->width >= unmappedzero) {
+ regalloc(&n4, types[tptr], &n3);
+ gmove(&n3, &n4);
+ n4.op = OINDREG;
+ n4.type = types[TUINT8];
+ n4.xoffset = 0;
+ gins(ATESTB, nodintconst(0), &n4);
+ regfree(&n4);
+ }
+
+ // constant index
+ if(isconst(nr, CTINT)) {
+ if(isconst(nl, CTSTR))
+ fatal("constant string constant index"); // front end should handle
+ v = mpgetfix(nr->val.u.xval);
+ if(isslice(nl->type) || nl->type->etype == TSTRING) {
+ if(!debug['B'] && !n->etype) {
+ n1 = n3;
+ n1.op = OINDREG;
+ n1.type = types[tptr];
+ n1.xoffset = Array_nel;
+ nodconst(&n2, types[TUINT32], v);
+ gins(optoas(OCMP, types[TUINT32]), &n1, &n2);
+ p1 = gbranch(optoas(OGT, types[TUINT32]), T);
+ ginscall(panicindex, 0);
+ patch(p1, pc);
+ }
+
+ n1 = n3;
+ n1.op = OINDREG;
+ n1.type = types[tptr];
+ n1.xoffset = Array_array;
+ gmove(&n1, &n3);
+ }
+
+ if (v*w != 0)
+ ginscon(optoas(OADD, types[tptr]), v*w, &n3);
+ gmove(&n3, res);
+ regfree(&n3);
+ break;
+ }
+
+ // type of the index
+ t = types[TUINT64];
+ if(issigned[n1.type->etype])
+ t = types[TINT64];
+
+ regalloc(&n2, t, &n1); // i
+ gmove(&n1, &n2);
+ regfree(&n1);
+
+ if(!debug['B'] && !n->etype) {
+ // check bounds
+ n5.op = OXXX;
+ t = types[TUINT32];
+ if(is64(nr->type))
+ t = types[TUINT64];
+ if(isconst(nl, CTSTR)) {
+ nodconst(&n1, t, nl->val.u.sval->len);
+ } else if(isslice(nl->type) || nl->type->etype == TSTRING) {
+ n1 = n3;
+ n1.op = OINDREG;
+ n1.type = types[TUINT32];
+ n1.xoffset = Array_nel;
+ if(is64(nr->type)) {
+ regalloc(&n5, t, N);
+ gmove(&n1, &n5);
+ n1 = n5;
+ }
+ } else {
+ nodconst(&n1, t, nl->type->bound);
+ }
+ gins(optoas(OCMP, t), &n2, &n1);
+ p1 = gbranch(optoas(OLT, t), T);
+ if(n5.op != OXXX)
+ regfree(&n5);
+ ginscall(panicindex, 0);
+ patch(p1, pc);
+ }
+
+ if(isconst(nl, CTSTR)) {
+ regalloc(&n3, types[tptr], res);
+ p1 = gins(ALEAQ, N, &n3);
+ datastring(nl->val.u.sval->s, nl->val.u.sval->len, &p1->from);
+ p1->from.scale = 1;
+ p1->from.index = n2.val.u.reg;
+ goto indexdone;
+ }
+
+ if(isslice(nl->type) || nl->type->etype == TSTRING) {
+ n1 = n3;
+ n1.op = OINDREG;
+ n1.type = types[tptr];
+ n1.xoffset = Array_array;
+ gmove(&n1, &n3);
+ }
+
+ if(w == 0) {
+ // nothing to do
+ } else if(w == 1 || w == 2 || w == 4 || w == 8) {
+ p1 = gins(ALEAQ, &n2, &n3);
+ p1->from.scale = w;
+ p1->from.index = p1->from.type;
+ p1->from.type = p1->to.type + D_INDIR;
+ } else {
+ ginscon(optoas(OMUL, t), w, &n2);
+ gins(optoas(OADD, types[tptr]), &n2, &n3);
+ }
+
+ indexdone:
+ gmove(&n3, res);
+ regfree(&n2);
+ regfree(&n3);
+ break;
+
+ case ONAME:
+ // should only get here with names in this func.
+ if(n->funcdepth > 0 && n->funcdepth != funcdepth) {
+ dump("bad agen", n);
+ fatal("agen: bad ONAME funcdepth %d != %d",
+ n->funcdepth, funcdepth);
+ }
+
+ // should only get here for heap vars or paramref
+ if(!(n->class & PHEAP) && n->class != PPARAMREF) {
+ dump("bad agen", n);
+ fatal("agen: bad ONAME class %#x", n->class);
+ }
+ cgen(n->heapaddr, res);
+ if(n->xoffset != 0)
+ ginscon(optoas(OADD, types[tptr]), n->xoffset, res);
+ break;
+
+ case OIND:
+ cgen(nl, res);
+ break;
+
+ case ODOT:
+ agen(nl, res);
+ if(n->xoffset != 0)
+ ginscon(optoas(OADD, types[tptr]), n->xoffset, res);
+ break;
+
+ case ODOTPTR:
+ cgen(nl, res);
+ if(n->xoffset != 0) {
+ // explicit check for nil if struct is large enough
+ // that we might derive too big a pointer.
+ if(nl->type->type->width >= unmappedzero) {
+ regalloc(&n1, types[tptr], res);
+ gmove(res, &n1);
+ n1.op = OINDREG;
+ n1.type = types[TUINT8];
+ n1.xoffset = 0;
+ gins(ATESTB, nodintconst(0), &n1);
+ regfree(&n1);
+ }
+ ginscon(optoas(OADD, types[tptr]), n->xoffset, res);
+ }
+ break;
+ }
+
+ret:
+ ;
+}
+
+/*
+ * generate:
+ * newreg = &n;
+ * res = newreg
+ *
+ * on exit, a has been changed to be *newreg.
+ * caller must regfree(a).
+ */
+void
+igen(Node *n, Node *a, Node *res)
+{
+ Type *fp;
+ Iter flist;
+
+ switch(n->op) {
+ case ONAME:
+ if((n->class&PHEAP) || n->class == PPARAMREF)
+ break;
+ *a = *n;
+ return;
+
+ case OCALLFUNC:
+ fp = structfirst(&flist, getoutarg(n->left->type));
+ cgen_call(n, 0);
+ memset(a, 0, sizeof *a);
+ a->op = OINDREG;
+ a->val.u.reg = D_SP;
+ a->addable = 1;
+ a->xoffset = fp->width;
+ a->type = n->type;
+ return;
+ }
+
+ regalloc(a, types[tptr], res);
+ agen(n, a);
+ a->op = OINDREG;
+ a->type = n->type;
+}
+
+/*
+ * generate:
+ * if(n == true) goto to;
+ */
+void
+bgen(Node *n, int true, Prog *to)
+{
+ int et, a;
+ Node *nl, *nr, *l, *r;
+ Node n1, n2, tmp;
+ Prog *p1, *p2;
+
+ if(debug['g']) {
+ dump("\nbgen", n);
+ }
+
+ if(n == N)
+ n = nodbool(1);
+
+ if(n->ninit != nil)
+ genlist(n->ninit);
+
+ nl = n->left;
+ nr = n->right;
+
+ if(n->type == T) {
+ convlit(&n, types[TBOOL]);
+ if(n->type == T)
+ goto ret;
+ }
+
+ et = n->type->etype;
+ if(et != TBOOL) {
+ yyerror("cgen: bad type %T for %O", n->type, n->op);
+ patch(gins(AEND, N, N), to);
+ goto ret;
+ }
+ nl = N;
+ nr = N;
+
+ switch(n->op) {
+ default:
+ def:
+ regalloc(&n1, n->type, N);
+ cgen(n, &n1);
+ nodconst(&n2, n->type, 0);
+ gins(optoas(OCMP, n->type), &n1, &n2);
+ a = AJNE;
+ if(!true)
+ a = AJEQ;
+ patch(gbranch(a, n->type), to);
+ regfree(&n1);
+ goto ret;
+
+ case OLITERAL:
+ // need to ask if it is bool?
+ if(!true == !n->val.u.bval)
+ patch(gbranch(AJMP, T), to);
+ goto ret;
+
+ case ONAME:
+ if(n->addable == 0)
+ goto def;
+ nodconst(&n1, n->type, 0);
+ gins(optoas(OCMP, n->type), n, &n1);
+ a = AJNE;
+ if(!true)
+ a = AJEQ;
+ patch(gbranch(a, n->type), to);
+ goto ret;
+
+ case OANDAND:
+ if(!true)
+ goto caseor;
+
+ caseand:
+ p1 = gbranch(AJMP, T);
+ p2 = gbranch(AJMP, T);
+ patch(p1, pc);
+ bgen(n->left, !true, p2);
+ bgen(n->right, !true, p2);
+ p1 = gbranch(AJMP, T);
+ patch(p1, to);
+ patch(p2, pc);
+ goto ret;
+
+ case OOROR:
+ if(!true)
+ goto caseand;
+
+ caseor:
+ bgen(n->left, true, to);
+ bgen(n->right, true, to);
+ goto ret;
+
+ case OEQ:
+ case ONE:
+ case OLT:
+ case OGT:
+ case OLE:
+ case OGE:
+ nr = n->right;
+ if(nr == N || nr->type == T)
+ goto ret;
+
+ case ONOT: // unary
+ nl = n->left;
+ if(nl == N || nl->type == T)
+ goto ret;
+ break;
+ }
+
+ switch(n->op) {
+
+ case ONOT:
+ bgen(nl, !true, to);
+ goto ret;
+
+ case OEQ:
+ case ONE:
+ case OLT:
+ case OGT:
+ case OLE:
+ case OGE:
+ a = n->op;
+ if(!true) {
+ if(isfloat[nr->type->etype]) {
+ // brcom is not valid on floats when NaN is involved.
+ p1 = gbranch(AJMP, T);
+ p2 = gbranch(AJMP, T);
+ patch(p1, pc);
+ bgen(n, 1, p2);
+ patch(gbranch(AJMP, T), to);
+ patch(p2, pc);
+ goto ret;
+ }
+ a = brcom(a);
+ true = !true;
+ }
+
+ // make simplest on right
+ if(nl->op == OLITERAL || (nl->ullman < nr->ullman && nl->ullman < UINF)) {
+ a = brrev(a);
+ r = nl;
+ nl = nr;
+ nr = r;
+ }
+
+ if(isslice(nl->type)) {
+ // only valid to cmp darray to literal nil
+ if((a != OEQ && a != ONE) || nr->op != OLITERAL) {
+ yyerror("illegal array comparison");
+ break;
+ }
+ a = optoas(a, types[tptr]);
+ regalloc(&n1, types[tptr], N);
+ agen(nl, &n1);
+ n2 = n1;
+ n2.op = OINDREG;
+ n2.xoffset = Array_array;
+ n2.type = types[tptr];
+ nodconst(&tmp, types[tptr], 0);
+ gins(optoas(OCMP, types[tptr]), &n2, &tmp);
+ patch(gbranch(a, types[tptr]), to);
+ regfree(&n1);
+ break;
+ }
+
+ if(isinter(nl->type)) {
+ // front end shold only leave cmp to literal nil
+ if((a != OEQ && a != ONE) || nr->op != OLITERAL) {
+ yyerror("illegal interface comparison");
+ break;
+ }
+ a = optoas(a, types[tptr]);
+ regalloc(&n1, types[tptr], N);
+ agen(nl, &n1);
+ n2 = n1;
+ n2.op = OINDREG;
+ n2.xoffset = 0;
+ nodconst(&tmp, types[tptr], 0);
+ gins(optoas(OCMP, types[tptr]), &n2, &tmp);
+ patch(gbranch(a, types[tptr]), to);
+ regfree(&n1);
+ break;
+ }
+ if(iscomplex[nl->type->etype]) {
+ complexbool(a, nl, nr, true, to);
+ break;
+ }
+
+ if(nr->ullman >= UINF) {
+ regalloc(&n1, nl->type, N);
+ cgen(nl, &n1);
+
+ tempname(&tmp, nl->type);
+ gmove(&n1, &tmp);
+ regfree(&n1);
+
+ regalloc(&n2, nr->type, N);
+ cgen(nr, &n2);
+
+ regalloc(&n1, nl->type, N);
+ cgen(&tmp, &n1);
+
+ goto cmp;
+ }
+
+ regalloc(&n1, nl->type, N);
+ cgen(nl, &n1);
+
+ if(smallintconst(nr)) {
+ gins(optoas(OCMP, nr->type), &n1, nr);
+ patch(gbranch(optoas(a, nr->type), nr->type), to);
+ regfree(&n1);
+ break;
+ }
+
+ regalloc(&n2, nr->type, N);
+ cgen(nr, &n2);
+ cmp:
+ // only < and <= work right with NaN; reverse if needed
+ l = &n1;
+ r = &n2;
+ if(isfloat[nl->type->etype] && (a == OGT || a == OGE)) {
+ l = &n2;
+ r = &n1;
+ a = brrev(a);
+ }
+
+ gins(optoas(OCMP, nr->type), l, r);
+
+ if(isfloat[nr->type->etype] && (n->op == OEQ || n->op == ONE)) {
+ if(n->op == OEQ) {
+ // neither NE nor P
+ p1 = gbranch(AJNE, T);
+ p2 = gbranch(AJPS, T);
+ patch(gbranch(AJMP, T), to);
+ patch(p1, pc);
+ patch(p2, pc);
+ } else {
+ // either NE or P
+ patch(gbranch(AJNE, T), to);
+ patch(gbranch(AJPS, T), to);
+ }
+ } else
+ patch(gbranch(optoas(a, nr->type), nr->type), to);
+ regfree(&n1);
+ regfree(&n2);
+ break;
+ }
+ goto ret;
+
+ret:
+ ;
+}
+
+/*
+ * n is on stack, either local variable
+ * or return value from function call.
+ * return n's offset from SP.
+ */
+int32
+stkof(Node *n)
+{
+ Type *t;
+ Iter flist;
+ int32 off;
+
+ switch(n->op) {
+ case OINDREG:
+ return n->xoffset;
+
+ case ODOT:
+ t = n->left->type;
+ if(isptr[t->etype])
+ break;
+ off = stkof(n->left);
+ if(off == -1000 || off == 1000)
+ return off;
+ return off + n->xoffset;
+
+ case OINDEX:
+ t = n->left->type;
+ if(!isfixedarray(t))
+ break;
+ off = stkof(n->left);
+ if(off == -1000 || off == 1000)
+ return off;
+ if(isconst(n->right, CTINT))
+ return off + t->type->width * mpgetfix(n->right->val.u.xval);
+ return 1000;
+
+ case OCALLMETH:
+ case OCALLINTER:
+ case OCALLFUNC:
+ t = n->left->type;
+ if(isptr[t->etype])
+ t = t->type;
+
+ t = structfirst(&flist, getoutarg(t));
+ if(t != T)
+ return t->width;
+ break;
+ }
+
+ // botch - probably failing to recognize address
+ // arithmetic on the above. eg INDEX and DOT
+ return -1000;
+}
+
+/*
+ * block copy:
+ * memmove(&ns, &n, w);
+ */
+void
+sgen(Node *n, Node *ns, int32 w)
+{
+ Node nodl, nodr, oldl, oldr, cx, oldcx, tmp;
+ int32 c, q, odst, osrc;
+
+ if(debug['g']) {
+ print("\nsgen w=%d\n", w);
+ dump("r", n);
+ dump("res", ns);
+ }
+ if(w == 0)
+ return;
+ if(n->ullman >= UINF && ns->ullman >= UINF) {
+ fatal("sgen UINF");
+ }
+
+ if(w < 0)
+ fatal("sgen copy %d", w);
+
+ if(w == 16)
+ if(componentgen(n, ns))
+ return;
+
+ // offset on the stack
+ osrc = stkof(n);
+ odst = stkof(ns);
+
+ if(osrc != -1000 && odst != -1000 && (osrc == 1000 || odst == 1000)) {
+ // osrc and odst both on stack, and at least one is in
+ // an unknown position. Could generate code to test
+ // for forward/backward copy, but instead just copy
+ // to a temporary location first.
+ tempname(&tmp, n->type);
+ sgen(n, &tmp, w);
+ sgen(&tmp, ns, w);
+ return;
+ }
+
+ if(n->ullman >= ns->ullman) {
+ savex(D_SI, &nodr, &oldr, N, types[tptr]);
+ agen(n, &nodr);
+
+ regalloc(&nodr, types[tptr], &nodr); // mark nodr as live
+ savex(D_DI, &nodl, &oldl, N, types[tptr]);
+ agen(ns, &nodl);
+ regfree(&nodr);
+ } else {
+ savex(D_DI, &nodl, &oldl, N, types[tptr]);
+ agen(ns, &nodl);
+
+ regalloc(&nodl, types[tptr], &nodl); // mark nodl as live
+ savex(D_SI, &nodr, &oldr, N, types[tptr]);
+ agen(n, &nodr);
+ regfree(&nodl);
+ }
+
+ c = w % 8; // bytes
+ q = w / 8; // quads
+
+ savex(D_CX, &cx, &oldcx, N, types[TINT64]);
+
+ // if we are copying forward on the stack and
+ // the src and dst overlap, then reverse direction
+ if(osrc < odst && odst < osrc+w) {
+ // reverse direction
+ gins(ASTD, N, N); // set direction flag
+ if(c > 0) {
+ gconreg(AADDQ, w-1, D_SI);
+ gconreg(AADDQ, w-1, D_DI);
+
+ gconreg(AMOVQ, c, D_CX);
+ gins(AREP, N, N); // repeat
+ gins(AMOVSB, N, N); // MOVB *(SI)-,*(DI)-
+ }
+
+ if(q > 0) {
+ if(c > 0) {
+ gconreg(AADDQ, -7, D_SI);
+ gconreg(AADDQ, -7, D_DI);
+ } else {
+ gconreg(AADDQ, w-8, D_SI);
+ gconreg(AADDQ, w-8, D_DI);
+ }
+ gconreg(AMOVQ, q, D_CX);
+ gins(AREP, N, N); // repeat
+ gins(AMOVSQ, N, N); // MOVQ *(SI)-,*(DI)-
+ }
+ // we leave with the flag clear
+ gins(ACLD, N, N);
+ } else {
+ // normal direction
+ if(q >= 4) {
+ gconreg(AMOVQ, q, D_CX);
+ gins(AREP, N, N); // repeat
+ gins(AMOVSQ, N, N); // MOVQ *(SI)+,*(DI)+
+ } else
+ while(q > 0) {
+ gins(AMOVSQ, N, N); // MOVQ *(SI)+,*(DI)+
+ q--;
+ }
+
+ if(c >= 4) {
+ gins(AMOVSL, N, N); // MOVL *(SI)+,*(DI)+
+ c -= 4;
+ }
+ while(c > 0) {
+ gins(AMOVSB, N, N); // MOVB *(SI)+,*(DI)+
+ c--;
+ }
+ }
+
+
+ restx(&nodl, &oldl);
+ restx(&nodr, &oldr);
+ restx(&cx, &oldcx);
+}
+
+static int
+cadable(Node *n)
+{
+ if(!n->addable) {
+ // dont know how it happens,
+ // but it does
+ return 0;
+ }
+
+ switch(n->op) {
+ case ONAME:
+ return 1;
+ }
+ return 0;
+}
+
+/*
+ * copy a structure component by component
+ * return 1 if can do, 0 if cant.
+ * nr is N for copy zero
+ */
+int
+componentgen(Node *nr, Node *nl)
+{
+ Node nodl, nodr;
+ int freel, freer;
+
+ freel = 0;
+ freer = 0;
+
+ switch(nl->type->etype) {
+ default:
+ goto no;
+
+ case TARRAY:
+ if(!isslice(nl->type))
+ goto no;
+ case TSTRING:
+ case TINTER:
+ break;
+ }
+
+ nodl = *nl;
+ if(!cadable(nl)) {
+ if(nr == N || !cadable(nr))
+ goto no;
+ igen(nl, &nodl, N);
+ freel = 1;
+ }
+
+ if(nr != N) {
+ nodr = *nr;
+ if(!cadable(nr)) {
+ igen(nr, &nodr, N);
+ freer = 1;
+ }
+ }
+
+ switch(nl->type->etype) {
+ case TARRAY:
+ if(!isslice(nl->type))
+ goto no;
+
+ nodl.xoffset += Array_array;
+ nodl.type = ptrto(nl->type->type);
+
+ if(nr != N) {
+ nodr.xoffset += Array_array;
+ nodr.type = nodl.type;
+ } else
+ nodconst(&nodr, nodl.type, 0);
+ gmove(&nodr, &nodl);
+
+ nodl.xoffset += Array_nel-Array_array;
+ nodl.type = types[TUINT32];
+
+ if(nr != N) {
+ nodr.xoffset += Array_nel-Array_array;
+ nodr.type = nodl.type;
+ } else
+ nodconst(&nodr, nodl.type, 0);
+ gmove(&nodr, &nodl);
+
+ nodl.xoffset += Array_cap-Array_nel;
+ nodl.type = types[TUINT32];
+
+ if(nr != N) {
+ nodr.xoffset += Array_cap-Array_nel;
+ nodr.type = nodl.type;
+ } else
+ nodconst(&nodr, nodl.type, 0);
+ gmove(&nodr, &nodl);
+
+ goto yes;
+
+ case TSTRING:
+ nodl.xoffset += Array_array;
+ nodl.type = ptrto(types[TUINT8]);
+
+ if(nr != N) {
+ nodr.xoffset += Array_array;
+ nodr.type = nodl.type;
+ } else
+ nodconst(&nodr, nodl.type, 0);
+ gmove(&nodr, &nodl);
+
+ nodl.xoffset += Array_nel-Array_array;
+ nodl.type = types[TUINT32];
+
+ if(nr != N) {
+ nodr.xoffset += Array_nel-Array_array;
+ nodr.type = nodl.type;
+ } else
+ nodconst(&nodr, nodl.type, 0);
+ gmove(&nodr, &nodl);
+
+ goto yes;
+
+ case TINTER:
+ nodl.xoffset += Array_array;
+ nodl.type = ptrto(types[TUINT8]);
+
+ if(nr != N) {
+ nodr.xoffset += Array_array;
+ nodr.type = nodl.type;
+ } else
+ nodconst(&nodr, nodl.type, 0);
+ gmove(&nodr, &nodl);
+
+ nodl.xoffset += Array_nel-Array_array;
+ nodl.type = ptrto(types[TUINT8]);
+
+ if(nr != N) {
+ nodr.xoffset += Array_nel-Array_array;
+ nodr.type = nodl.type;
+ } else
+ nodconst(&nodr, nodl.type, 0);
+ gmove(&nodr, &nodl);
+
+ goto yes;
+
+ case TSTRUCT:
+ goto no;
+ }
+
+no:
+ if(freer)
+ regfree(&nodr);
+ if(freel)
+ regfree(&nodl);
+ return 0;
+
+yes:
+ if(freer)
+ regfree(&nodr);
+ if(freel)
+ regfree(&nodl);
+ return 1;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2025-07-21 15:48:12 +0000