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// Inferno utils/6c/swt.c
// http://code.google.com/p/inferno-os/source/browse/utils/6c/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 "gc.h"
int
swcmp(const void *a1, const void *a2)
{
C1 *p1, *p2;
p1 = (C1*)a1;
p2 = (C1*)a2;
if(p1->val < p2->val)
return -1;
return p1->val > p2->val;
}
void
doswit(Node *n)
{
Case *c;
C1 *q, *iq;
int32 def, nc, i, isv;
def = 0;
nc = 0;
isv = 0;
for(c = cases; c->link != C; c = c->link) {
if(c->def) {
if(def)
diag(n, "more than one default in switch");
def = c->label;
continue;
}
isv |= c->isv;
nc++;
}
if(isv && !typev[n->type->etype])
warn(n, "32-bit switch expression with 64-bit case constant");
iq = alloc(nc*sizeof(C1));
q = iq;
for(c = cases; c->link != C; c = c->link) {
if(c->def)
continue;
q->label = c->label;
if(isv)
q->val = c->val;
else
q->val = (int32)c->val; /* cast ensures correct value for 32-bit switch on 64-bit architecture */
q++;
}
qsort(iq, nc, sizeof(C1), swcmp);
if(debug['W'])
for(i=0; i<nc; i++)
print("case %2d: = %.8llux\n", i, (vlong)iq[i].val);
for(i=0; i<nc-1; i++)
if(iq[i].val == iq[i+1].val)
diag(n, "duplicate cases in switch %lld", (vlong)iq[i].val);
if(def == 0) {
def = breakpc;
nbreak++;
}
swit1(iq, nc, def, n);
}
void
cas(void)
{
Case *c;
c = alloc(sizeof(*c));
c->link = cases;
cases = c;
}
int32
outlstring(ushort *s, int32 n)
{
char buf[2];
int c;
int32 r;
if(suppress)
return nstring;
while(nstring & 1)
outstring("", 1);
r = nstring;
while(n > 0) {
c = *s++;
if(align(0, types[TCHAR], Aarg1, nil)) {
buf[0] = c>>8;
buf[1] = c;
} else {
buf[0] = c;
buf[1] = c>>8;
}
outstring(buf, 2);
n -= sizeof(ushort);
}
return r;
}
void
nullwarn(Node *l, Node *r)
{
warn(Z, "result of operation not used");
if(l != Z)
cgen(l, Z);
if(r != Z)
cgen(r, Z);
}
void
ieeedtod(Ieee *ieee, double native)
{
double fr, ho, f;
int exp;
if(native < 0) {
ieeedtod(ieee, -native);
ieee->h |= 0x80000000L;
return;
}
if(native == 0) {
ieee->l = 0;
ieee->h = 0;
return;
}
fr = frexp(native, &exp);
f = 2097152L; /* shouldnt use fp constants here */
fr = modf(fr*f, &ho);
ieee->h = ho;
ieee->h &= 0xfffffL;
ieee->h |= (exp+1022L) << 20;
f = 65536L;
fr = modf(fr*f, &ho);
ieee->l = ho;
ieee->l <<= 16;
ieee->l |= (int32)(fr*f);
}