1
0
mirror of https://github.com/golang/go synced 2024-10-04 12:31:21 -06:00
go/src/cmd/5g/gobj.c
Russ Cox 4acb70d377 cmd/gc: bypass DATA instruction for data initialized to integer constant
Eventually we will want to bypass DATA for everything,
but the relocations are not standardized well enough across
architectures to make that possible.

This did not help as much as I expected, but it is definitely better.
It shaves maybe 1-2% off all.bash depending on how much you
trust the timings of a single run:

Before: 241.139r 362.702u 112.967s
After:  234.339r 359.623u 111.045s

R=golang-codereviews, gobot, r, iant
CC=golang-codereviews
https://golang.org/cl/44650043
2013-12-20 14:24:39 -05:00

253 lines
5.3 KiB
C

// Derived from Inferno utils/5c/swt.c
// http://code.google.com/p/inferno-os/source/browse/utils/5c/swt.c
//
// Copyright © 1994-1999 Lucent Technologies Inc. All rights reserved.
// Portions Copyright © 1995-1997 C H Forsyth (forsyth@terzarima.net)
// Portions Copyright © 1997-1999 Vita Nuova Limited
// Portions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com)
// Portions Copyright © 2004,2006 Bruce Ellis
// Portions Copyright © 2005-2007 C H Forsyth (forsyth@terzarima.net)
// Revisions Copyright © 2000-2007 Lucent Technologies Inc. and others
// Portions Copyright © 2009 The Go Authors. All rights reserved.
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
#include <u.h>
#include <libc.h>
#include "gg.h"
int
dsname(Sym *sym, int off, char *t, int n)
{
Prog *p;
p = gins(ADATA, N, N);
p->from.type = D_OREG;
p->from.name = D_EXTERN;
p->from.etype = TINT32;
p->from.offset = off;
p->from.reg = NREG;
p->from.sym = linksym(sym);
p->reg = n;
p->to.type = D_SCONST;
p->to.name = D_NONE;
p->to.reg = NREG;
p->to.offset = 0;
memmove(p->to.u.sval, t, n);
return off + n;
}
/*
* make a refer to the data s, s+len
* emitting DATA if needed.
*/
void
datastring(char *s, int len, Addr *a)
{
Sym *sym;
sym = stringsym(s, len);
a->type = D_OREG;
a->name = D_EXTERN;
a->etype = TINT32;
a->offset = widthptr+4; // skip header
a->reg = NREG;
a->sym = linksym(sym);
a->node = sym->def;
}
/*
* make a refer to the string sval,
* emitting DATA if needed.
*/
void
datagostring(Strlit *sval, Addr *a)
{
Sym *sym;
sym = stringsym(sval->s, sval->len);
a->type = D_OREG;
a->name = D_EXTERN;
a->etype = TINT32;
a->offset = 0; // header
a->reg = NREG;
a->sym = linksym(sym);
a->node = sym->def;
}
void
gdata(Node *nam, Node *nr, int wid)
{
Prog *p;
vlong v;
if(nr->op == OLITERAL) {
switch(nr->val.ctype) {
case CTCPLX:
gdatacomplex(nam, nr->val.u.cval);
return;
case CTSTR:
gdatastring(nam, nr->val.u.sval);
return;
}
}
if(wid == 8 && is64(nr->type)) {
v = mpgetfix(nr->val.u.xval);
p = gins(ADATA, nam, nodintconst(v));
p->reg = 4;
p = gins(ADATA, nam, nodintconst(v>>32));
p->reg = 4;
p->from.offset += 4;
return;
}
p = gins(ADATA, nam, nr);
p->reg = wid;
}
void
gdatacomplex(Node *nam, Mpcplx *cval)
{
Prog *p;
int w;
w = cplxsubtype(nam->type->etype);
w = types[w]->width;
p = gins(ADATA, nam, N);
p->reg = w;
p->to.type = D_FCONST;
p->to.u.dval = mpgetflt(&cval->real);
p = gins(ADATA, nam, N);
p->reg = w;
p->from.offset += w;
p->to.type = D_FCONST;
p->to.u.dval = mpgetflt(&cval->imag);
}
void
gdatastring(Node *nam, Strlit *sval)
{
Prog *p;
Node nod1;
p = gins(ADATA, nam, N);
datastring(sval->s, sval->len, &p->to);
p->reg = types[tptr]->width;
p->to.type = D_CONST;
p->to.etype = TINT32;
//print("%P\n", p);
nodconst(&nod1, types[TINT32], sval->len);
p = gins(ADATA, nam, &nod1);
p->reg = types[TINT32]->width;
p->from.offset += types[tptr]->width;
}
int
dstringptr(Sym *s, int off, char *str)
{
Prog *p;
off = rnd(off, widthptr);
p = gins(ADATA, N, N);
p->from.type = D_OREG;
p->from.name = D_EXTERN;
p->from.sym = linksym(s);
p->from.offset = off;
p->reg = widthptr;
datastring(str, strlen(str)+1, &p->to);
p->to.type = D_CONST;
p->to.etype = TINT32;
off += widthptr;
return off;
}
int
dgostrlitptr(Sym *s, int off, Strlit *lit)
{
Prog *p;
if(lit == nil)
return duintptr(s, off, 0);
off = rnd(off, widthptr);
p = gins(ADATA, N, N);
p->from.type = D_OREG;
p->from.name = D_EXTERN;
p->from.sym = linksym(s);
p->from.offset = off;
p->reg = widthptr;
datagostring(lit, &p->to);
p->to.type = D_CONST;
p->to.etype = TINT32;
off += widthptr;
return off;
}
int
dgostringptr(Sym *s, int off, char *str)
{
int n;
Strlit *lit;
if(str == nil)
return duintptr(s, off, 0);
n = strlen(str);
lit = mal(sizeof *lit + n);
strcpy(lit->s, str);
lit->len = n;
return dgostrlitptr(s, off, lit);
}
int
dsymptr(Sym *s, int off, Sym *x, int xoff)
{
Prog *p;
off = rnd(off, widthptr);
p = gins(ADATA, N, N);
p->from.type = D_OREG;
p->from.name = D_EXTERN;
p->from.sym = linksym(s);
p->from.offset = off;
p->reg = widthptr;
p->to.type = D_CONST;
p->to.name = D_EXTERN;
p->to.sym = linksym(x);
p->to.offset = xoff;
off += widthptr;
return off;
}
void
nopout(Prog *p)
{
p->as = ANOP;
}