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save callee-save registers

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This commit is contained in:
Quentin Carbonneaux 2015-09-20 17:46:17 -04:00
parent dab9590ce7
commit 9fcad221d0
4 changed files with 50 additions and 23 deletions
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20
lisc/emit.c
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@ -286,14 +286,17 @@ eins(Ins i, Fn *fn, FILE *f)
static int
framesz(Fn *fn)
{
int i, a, f;
int i, o, a, f;
for (i=0, o=0; i<NRClob; i++)
o ^= 1 & (fn->reg >> rclob[i]);
f = 0;
for (i=NAlign-1, a=1<<i; i>=0; i--, a/=2)
if (f == 0 || f - a == fn->svec[i])
f = fn->svec[i];
a = 1 << (NAlign-2);
while ((f + a) % (2 * a) != a)
o *= a;
while ((f + o) % (2 * a))
f += a - f % a;
return f * 16 / (1 << (NAlign-1));
}
@ -303,7 +306,7 @@ emitfn(Fn *fn, FILE *f)
{
Blk *b, *s;
Ins *i;
int c, fs;
int r, j, c, fs;
fprintf(f,
".text\n"
@ -317,12 +320,23 @@ emitfn(Fn *fn, FILE *f)
fs = framesz(fn);
if (fs)
fprintf(f, "\tsub $%d, %%rsp\n", fs);
for (j=0; j<NRClob; j++) {
r = rclob[j];
if (fn->reg & BIT(r))
emitf(fn, f, "\tpush%w %R\n", 1, TMP(r));
}
for (b=fn->start; b; b=b->link) {
fprintf(f, ".L%s:\n", b->name);
for (i=b->ins; i-b->ins < b->nins; i++)
eins(*i, fn, f);
switch (b->jmp.type) {
case JRet:
for (j=NRClob; j>=0; j--) {
r = rclob[j];
if (fn->reg & BIT(r))
emitf(fn, f, "\tpop%w %R\n", 1, TMP(r));
}
fprintf(f,
"\tleave\n"
"\tret\n"