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Diffstat (limited to 'c.c')
-rw-r--r--c.c169
1 files changed, 120 insertions, 49 deletions
diff --git a/c.c b/c.c
index a715888..7b64b8f 100644
--- a/c.c
+++ b/c.c
@@ -1518,6 +1518,7 @@ buildagg(struct comp *cm, enum typetag tt, const char *name, int id)
struct declstate st = { DFIELD };
do {
struct decl decl = pdecl(&st, cm);
+ uint tysize = typesize(decl.ty);
if (fld.n && td.flexi) {
td.flexi = 0;
error(&flexspan, "flexible array member is not at end of struct");
@@ -1542,9 +1543,9 @@ buildagg(struct comp *cm, enum typetag tt, const char *name, int id)
error(&ex.span, "cannot evaluate integer constant expression");
} else if (ex.i < 0) {
error(&ex.span, "bit-field '%s' has negative width '%ld'", name, ex.i);
- } else if (ex.i > 8*typesize(decl.ty)) {
+ } else if (ex.i > 8*tysize) {
error(&ex.span, "width of bit-field '%s' (%ld) exceeds width of type (%d)",
- name, ex.i, 8*typesize(decl.ty));
+ name, ex.i, 8*tysize);
} else if (ex.i == 0 && decl.name) {
error(&ex.span, "named bit-field '%s' has zero width", name);
} else {
@@ -1555,7 +1556,7 @@ buildagg(struct comp *cm, enum typetag tt, const char *name, int id)
bitfbyteoff = alignup(bitfbyteoff, typealign(decl.ty));
}
bitoff = 0;
- } else if (bitftypesiz && bitftypesiz < typesize(decl.ty)) {
+ } else if (bitftypesiz && bitftypesiz < tysize) {
/* end of previous bitfield */
bitoff = 0;
bitfbyteoff += bitftypesiz;
@@ -1567,7 +1568,7 @@ buildagg(struct comp *cm, enum typetag tt, const char *name, int id)
bitoff = 0;
bitfbyteoff += bitftypesiz;
}
- if (typesize(decl.ty) > bitftypesiz) bitftypesiz = typesize(decl.ty);
+ if (tysize > bitftypesiz) bitftypesiz = tysize;
}
pdecl(&st, cm);
} else {
@@ -1575,7 +1576,7 @@ buildagg(struct comp *cm, enum typetag tt, const char *name, int id)
}
if (decl.ty.t) {
uint align = typealign(decl.ty);
- uint siz = typesize(decl.ty);
+ uint siz = tysize;
uint off = bitftypesiz ? bitfbyteoff : isunion ? 0 : alignup(td.siz, align);
struct namedfield f = { decl.name, { decl.ty, off, bitsiz, bitoff, .qual = decl.qual }};
if (bitftypesiz && siz != bitftypesiz) while (f.f.bitoff + f.f.bitsiz > 8*siz) {
@@ -1592,8 +1593,6 @@ buildagg(struct comp *cm, enum typetag tt, const char *name, int id)
decl.ty.t == TYUNION ? "union" : "struct");
}
}
- if (bitftypesiz &&decl.name)
- efmt("bitf %s %d[%d:%d]\n", decl.name,f.f.off, f.f.bitoff, f.f.bitoff+f.f.bitsiz-1);
if (decl.name || !bitftypesiz)
vpush(&fld, f);
td.anyconst |= decl.qual & QCONST;
@@ -2351,7 +2350,7 @@ mkhiddensym(const char *fnname, const char *name, int id)
char buf[200];
struct wbuf wbuf = MEMBUF(buf, sizeof buf);
assert(id > 0);
- bfmt(&wbuf, "%s.%s.%d", fnname, name, id);
+ bfmt(&wbuf, "%s.%s.%d", fnname, name, id-1);
ioputc(&wbuf, 0);
assert(!wbuf.err);
return intern(buf);
@@ -2490,23 +2489,35 @@ cvt(struct function *fn, enum typetag to, enum typetag from, union ref ref)
}
static union ref
-narrow(struct function *fn, enum irclass to, enum typetag tt, union ref ref)
+narrow(struct function *fn, enum irclass to, enum typetag tt, union ref ref, uint bitsiz)
{
struct instr ins = {0};
assert(isscalart(tt));
- if (targ_primsizes[tt] >= cls2siz[to]) return ref;
- ins.cls = to;
- if (isfltt(tt)) {
- assert(to == KF4 && tt == TYDOUBLE);
- ins.op = Ocvtf8f4;
- } else {
- static const enum op ext[5][2] = {
- [1] = {Oextu1, Oexts1}, [2] = {Oextu2, Oexts2}, [4] = {Oextu4, Oexts4}
- };
- ins.op = ext[targ_primsizes[tt]][issignedt(tt)];
+ if (targ_primsizes[tt] < cls2siz[to]) {
+ ins.cls = to;
+ if (isfltt(tt)) {
+ assert(to == KF4 && tt == TYDOUBLE);
+ ins.op = Ocvtf8f4;
+ } else {
+ static const enum op ext[5][2] = {
+ [1] = {Oextu1, Oexts1}, [2] = {Oextu2, Oexts2}, [4] = {Oextu4, Oexts4}
+ };
+ ins.op = ext[targ_primsizes[tt]][issignedt(tt)];
+ }
+ ins.l = ref;
+ ref = addinstr(fn, ins);
}
- ins.l = ref;
- return addinstr(fn, ins);
+ if (bitsiz) {
+ assert(kisint(to) && isintt(tt) && bitsiz < 8*targ_primsizes[tt]);
+ if (!issignedt(tt)) {
+ ref = addinstr(fn, mkinstr(Oand, to, .l = ref, .r = mkintcon(to, (1ull<<bitsiz)-1)));
+ } else {
+ uint sh = 8*cls2siz[to] - bitsiz;
+ ref = addinstr(fn, mkinstr(Oshl, to, .l = ref, .r = mkref(RICON, sh)));
+ ref = addinstr(fn, mkinstr(Osar, to, .l = ref, .r = mkref(RICON, sh)));
+ }
+ }
+ return ref;
}
union ref
@@ -2691,19 +2702,20 @@ compilecall(struct function *fn, const struct expr *ex)
}
static union ref
-getbits(struct function *fn, const union type ty, union ref addr, uint off, int bitsiz, int bitoff)
+genbitfload(struct function *fn, const union type ty, union ref *addr, const struct exgetfld *fld)
{
enum irclass k = type2cls[ty.t];
+ uint off = fld->off, bitsiz = fld->bitsiz, bitoff = fld->bitoff;
union ref tmp;
uvlong mask;
if (off > 0)
- addr = addinstr(fn, mkinstr(Oadd, KPTR, .l = addr, .r = mkintcon(KI4, off)));
- tmp = genload(fn, ty, addr);
+ *addr = addinstr(fn, mkinstr(Oadd, KPTR, .l = *addr, .r = mkintcon(KI4, off)));
+ tmp = genload(fn, ty, *addr);
if (!issigned(ty)) {
/* shift right and mask */
if (bitoff > 0)
- tmp = addinstr(fn, mkinstr(Oslr, k, .l = tmp, .r = mkintcon(KI4, bitoff)));
+ tmp = addinstr(fn, mkinstr(Oslr, k, .l = tmp, .r = mkref(RICON, bitoff)));
if (bitsiz < 8*typesize(ty)) {
mask = bitsiz == 64 ? -1ull : (1ull << bitsiz) - 1;
tmp = addinstr(fn, mkinstr(Oand, k, .l = tmp, .r = mkintcon(k, mask)));
@@ -2712,19 +2724,54 @@ getbits(struct function *fn, const union type ty, union ref addr, uint off, int
/* shift left and shift right arithmetic to propagate sign bit */
int sh = 8*cls2siz[k] - bitsiz - bitoff;
if (sh)
- tmp = addinstr(fn, mkinstr(Oshl, k, .l = tmp, .r = mkintcon(KI4, sh)));
- sh = 8*cls2siz[k] - sh + bitoff;
+ tmp = addinstr(fn, mkinstr(Oshl, k, .l = tmp, .r = mkref(RICON, sh)));
+ sh += bitoff;
if (sh)
- tmp = addinstr(fn, mkinstr(Osar, k, .l = tmp, .r = mkintcon(KI4, sh)));
+ tmp = addinstr(fn, mkinstr(Osar, k, .l = tmp, .r = mkref(RICON, sh)));
}
return tmp;
}
+static void
+genbitfstore(struct function *fn, const union type ty, union ref addr,
+ const struct exgetfld *fld, union ref tmp, union ref val)
+{
+ enum irclass k = type2cls[ty.t];
+ uint off = fld->off, bitsiz = fld->bitsiz, bitoff = fld->bitoff;
+ uint bittypesize = 8*typesize(ty);
+ uvlong mask;
+
+ if (!tmp.bits) {
+ if (off > 0)
+ addr = addinstr(fn, mkinstr(Oadd, KPTR, .l = addr, .r = mkintcon(KI4, off)));
+ tmp = genload(fn, ty, addr);
+ }
+ mask = (bitsiz == 64 ? -1ull : (1ull << bitsiz) - 1) << bitoff;
+
+ /* mask out bits in existing container */
+ tmp = addinstr(fn, mkinstr(Oand, k, .l = tmp, .r = mkintcon(k, ~mask)));
+
+ /* shift and mask source value */
+ if (isintcon(val)) {
+ val = mkintcon(k, ((uvlong)intconval(val) << bitoff) & mask);
+ } else {
+ if (bitoff)
+ val = addinstr(fn, mkinstr(Oshl, k, .l = val, .r = mkref(RICON, bitoff)));
+ if (bitsiz < bittypesize)
+ val = addinstr(fn, mkinstr(Oand, k, .l = val, .r = mkintcon(k, mask)));
+ }
+ /* combine and write */
+ if (bitsiz < bittypesize)
+ val = addinstr(fn, mkinstr(Oior, k, .l = tmp, .r = val));
+ genstore(fn, ty, addr, val);
+}
+
static union ref
compileexpr(struct function *fn, const struct expr *ex, bool discard)
{
union type ty;
union ref r, q;
+ uint bitsiz;
enum irclass cls = type2cls[ex->ty.t];
struct instr ins = {0};
int swp = 0;
@@ -2748,8 +2795,11 @@ compileexpr(struct function *fn, const struct expr *ex, bool discard)
return genload(fn, ex->ty, expraddr(fn, ex));
case EGETF:
if (discard && !(ex->qual & QVOLATILE)) return NOREF;
- if (ex->fld.bitsiz)
- return getbits(fn, ex->ty, expraddr(fn, ex->sub), ex->fld.off, ex->fld.bitsiz, ex->fld.bitoff);
+ if (ex->fld.bitsiz) {
+ /* bit-field */
+ r = expraddr(fn, ex->sub);
+ return genbitfload(fn, ex->ty, &r, &ex->fld);
+ }
return genload(fn, ex->ty, expraddr(fn, ex));
case ECAST:
if (ex->ty.t == TYVOID) {
@@ -2861,7 +2911,7 @@ compileexpr(struct function *fn, const struct expr *ex, bool discard)
q = addinstr(fn, ins);
genstore(fn, sub->ty, r, q);
if (discard) return NOREF;
- return narrow(fn, cls, ex->ty.t, q);
+ return narrow(fn, cls, ex->ty.t, q, 0);
case EEQU:
ins.op = Oequ;
goto Cmp;
@@ -2894,10 +2944,17 @@ compileexpr(struct function *fn, const struct expr *ex, bool discard)
case ESET:
assert(isscalar(ex->ty));
q = cvt(fn, sub[0].ty.t, sub[1].ty.t, exprvalue(fn, &sub[1]));
- r = expraddr(fn, &sub[0]);
- genstore(fn, ex->ty, r, q);
+ if (sub[0].t == EGETF && (bitsiz = sub[0].fld.bitsiz)) {
+ /* bit-field */
+ r = expraddr(fn, &sub[0].sub[0]);
+ genbitfstore(fn, ex->ty, r, &sub[0].fld, NOREF, q);
+ } else {
+ bitsiz = 0;
+ r = expraddr(fn, &sub[0]);
+ genstore(fn, ex->ty, r, q);
+ }
if (discard) return NOREF;
- return narrow(fn, cls, sub[0].ty.t, q);
+ return narrow(fn, cls, sub[0].ty.t, q, bitsiz);
case ESETMUL:
ins.op = isunsigned(ex->ty) ? Oumul : Omul;
goto Compound;
@@ -2928,26 +2985,35 @@ compileexpr(struct function *fn, const struct expr *ex, bool discard)
case ESETADD:
ins.op = Oadd;
Compound:
- r = expraddr(fn, &sub[0]);
ty = in_range(ex->t, ESETSHL, ESETSHR) ? mktype(intpromote(ex->ty.t))
: cvtarith(sub[0].ty, sub[1].ty);
ins.cls = cls;
- ins.l = genload(fn, ex->ty, r);
ins.r = exprvalue(fn, &sub[1]);
- if ((ins.op != Oadd && ins.op != Osub) || cls != KPTR) {
- ins.l = cvt(fn, ty.t, sub[0].ty.t, ins.l);
- ins.r = cvt(fn, ex->ty.t, sub[1].ty.t, ins.r);
+ if (sub[0].t == EGETF && (bitsiz = sub[0].fld.bitsiz)) {
+ /* bit-field */
+ r = expraddr(fn, &sub[0].sub[0]);
+ ins.l = genbitfload(fn, sub[0].ty, &r, &sub[0].fld);
q = addinstr(fn, ins);
+ genbitfstore(fn, sub[0].ty, r, &sub[0].fld, ins.l, q);
} else {
- q = genptroff(fn, ins.op, typesize(typechild(ex->ty)), ins.l, sub[1].ty.t, ins.r);
+ bitsiz = 0;
+ r = expraddr(fn, &sub[0]);
+ ins.l = genload(fn, ex->ty, r);
+ if ((ins.op != Oadd && ins.op != Osub) || cls != KPTR) {
+ ins.l = cvt(fn, ty.t, sub[0].ty.t, ins.l);
+ ins.r = cvt(fn, ex->ty.t, sub[1].ty.t, ins.r);
+ q = addinstr(fn, ins);
+ } else {
+ q = genptroff(fn, ins.op, typesize(typechild(ex->ty)), ins.l, sub[1].ty.t, ins.r);
+ }
+ genstore(fn, ex->ty, r, q);
}
- genstore(fn, ex->ty, r, q);
if (discard) return NOREF;
- return narrow(fn, cls, ex->ty.t, q);
+ return narrow(fn, cls, ex->ty.t, q, bitsiz);
case ECALL:
r = compilecall(fn, ex);
if (isint(ex->ty))
- return narrow(fn, cls, ex->ty.t, r);
+ return narrow(fn, cls, ex->ty.t, r, 0);
return r;
case ECOND:
if (ex->ty.t == TYVOID) {
@@ -3404,17 +3470,17 @@ localdecl(struct comp *cm, struct function *fn, bool forini)
/* globl? */ decl.scls == SCEXTERN, decl.qual, name);
pdecl(&st, cm);
if (!statik) {
- if (!assigncheck(decl.ty, &ini)) {
+ if (!assigncheck(d->ty, &ini)) {
struct span span = decl.span;
joinspan(&span.ex, ini.span.ex);
error(&span, "cannot initialize '%ty' variable with '%ty'",
- decl.ty, ini.ty);
+ d->ty, ini.ty);
}
EMITS {
- if (isagg(decl.ty))
- structcopy(fn, decl.ty, mkref(RTMP, decl.id), expraddr(fn, &ini));
+ if (isagg(d->ty))
+ structcopy(fn, d->ty, mkref(RTMP, decl.id), expraddr(fn, &ini));
else
- genstore(fn, decl.ty, mkref(RTMP, decl.id), exprvalue(fn, &ini));
+ genstore(fn, d->ty, mkref(RTMP, decl.id), exprvalue(fn, &ini));
}
} else if (decl.scls == SCEXTERN) {
struct span span = decl.span;
@@ -3423,7 +3489,12 @@ localdecl(struct comp *cm, struct function *fn, bool forini)
"declaration of block local with extern linkage cannot have an initializer");
}
} else if (decl.scls == SCSTATIC) {
- assert(0);
+ /* zero-initialized static */
+ const char *sym = mkhiddensym(fn->name, decl.name, decl.id);
+ if (decl.ty.t == TYARRAY && isincomplete(decl.ty))
+ error(&decl.span, "definition of variable with array type needs size or initializer");
+ else
+ objnewdat(sym, Sbss, 0, typesize(decl.ty), typealign(decl.ty));
}
break;
case SCTYPEDEF:
generated by cgit v1.2.3 (git 2.39.1) at 2026-05-02 03:58:49 +0000