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authorlemon <lsof@mailbox.org>2026-03-17 13:22:00 +0100
committerlemon <lsof@mailbox.org>2026-03-17 13:22:00 +0100
commita8d6f8bf30c07edb775e56889f568ca20240bedf (patch)
treeb5a452b2675b2400f15013617291fe6061180bbf /src/c.c
parent24f14b7ad1af08d872971d72ce089a529911f657 (diff)
REFACTOR: move sources to src/
Diffstat (limited to 'src/c.c')
-rw-r--r--src/c.c4772
1 files changed, 4772 insertions, 0 deletions
diff --git a/src/c.c b/src/c.c
new file mode 100644
index 0000000..63c3f7f
--- /dev/null
+++ b/src/c.c
@@ -0,0 +1,4772 @@
+#include "c.h"
+#include "lex.h"
+#include "../endian.h"
+#include "../ir/ir.h"
+#include "../obj/obj.h"
+
+/** Parsing helper functions **/
+#define peek(Cm,Tk) lexpeek((Cm)->lx,Tk)
+static int
+lexc(struct comp *cm, struct token *tk)
+{
+ struct token tk2, tk_[1];
+ int t = lex(cm->lx, tk ? tk : tk_);
+ if (t == TKSTRLIT && peek(cm, &tk2) == TKSTRLIT && tk2.wide == tk->wide) {
+ /* 5.1.1.2 Translation phase 6: concatenate adjacent string literal tokens */
+ static char buf[200];
+ vec_of(char) rest = VINIT(buf, sizeof buf);
+ do {
+ lex(cm->lx, NULL);
+ if (tk) {
+ joinspan(&tk->span.ex, tk2.span.ex);
+ if (!tk->wide)
+ vpushn(&rest, tk2.s, tk2.len);
+ else if (tk->wide && targ_primsizes[targ_wchartype] == 2)
+ vpushn(&rest, tk2.ws16, tk2.len*2);
+ else
+ vpushn(&rest, tk2.ws32, tk2.len*4);
+ }
+ } while (peek(cm, &tk2) == TKSTRLIT && tk2.wide == tk->wide);
+ if (tk) {
+ if (!tk->wide) {
+ tk->s = memcpy(alloc(&cm->exarena, tk->len + rest.n, 1), tk->s, tk->len);
+ memcpy((char *)tk->s + tk->len, rest.p, rest.n);
+ tk->len += rest.n;
+ } else if (tk->wide == 1) {
+ tk->ws16 = memcpy(alloc(&cm->exarena, tk->len + rest.n*2, 2), tk->ws16, tk->len*2);
+ memcpy((short *)tk->s + tk->len, rest.p, rest.n);
+ tk->len += rest.n * 2;
+ } else {
+ tk->ws32 = memcpy(alloc(&cm->exarena, tk->len + rest.n*4, 4), tk->ws32, tk->len*4);
+ memcpy((int *)tk->s + tk->len, rest.p, rest.n);
+ tk->len += rest.n * 4;
+ }
+ }
+ vfree(&rest);
+ }
+ if (ccopt.pedant && in_range(t, TKWBEGIN_, TKWEND_) && (tk = tk ? tk : tk_)->extwarn) {
+ static struct bitset already[BSSIZE(TKWEND_-TKWBEGIN_+1)];
+ if (!bstest(already, t-TKWBEGIN_)) {
+ bsset(already, t-TKWBEGIN_);
+ warn(&tk->span, "%'tk in %M is an extension", tk);
+ }
+ }
+ return t;
+}
+#define lex(Cm,Tk) lexc(Cm,Tk)
+static bool
+match(struct comp *cm, struct token *tk, enum toktag t)
+{
+ if (peek(cm, NULL) == t) {
+ lex(cm, tk);
+ return 1;
+ }
+ return 0;
+}
+static bool
+expect(struct comp *cm, enum toktag t, const char *s)
+{
+ struct token tk;
+ if (!match(cm, &tk, t)) {
+ peek(cm, &tk);
+ if (aisprint(t)) tk.span.ex.len = tk.span.sl.len = 1;
+ error(&tk.span, "expected %'tt%s%s", t, s?" ":"",s ? s : "");
+ return 0;
+ }
+ return 1;
+}
+
+/******************************************/
+/* Data structures for declaration parser */
+/******************************************/
+
+enum declkind {
+ DTOPLEVEL,
+ DFUNCPARAM,
+ DFUNCVAR,
+ DFIELD,
+ DCASTEXPR,
+};
+
+/* Since a declaration can have multiple declarators, and we need to process
+ * each one individually, the declaration parser is a state machine
+ * (conceptually a generator coroutine); the state is zero-initialized (except
+ * for the .kind field), each call to pdecl yields the next individual decl,
+ * st.more indicates whether there are more decls left to parse (the coroutine
+ * has yielded), or this declaration list is done (the coroutine has finalized)
+ */
+struct declstate {
+ enum declkind kind;
+ union type base;
+ uchar scls;
+ uchar qual;
+ bool fnnoreturn : 1,
+ fninline : 1;
+ uint align;
+ bool base0, /* caller set initial base type, but there may be declspecs to parse */
+ more, /* caller should keep calling pdecl to get next decl */
+ varini, /* caller should parse an initializer ('=' <ini>) and
+ call pdecl() to advance state before checking .more */
+ funcdef, /* caller should parse an func definition ('{' <body> '}').
+ the declaration list is finished. */
+ bitf, /* caller should parse a bitfield size and
+ call pdecl() to advance state before checking .more */
+ tagdecl, /* declarator is a tagged type */
+ empty; /* nothing decl (';') */
+ internstr *pnames; /* param names for function definition */
+ struct span *pspans; /* param spans ditto */
+ uchar *pqual; /* param quals ditto */
+ int attr;
+};
+static struct decl pdecl(struct declstate *st, struct comp *cm);
+
+static struct decl *finddecl(struct comp *cm, internstr name);
+
+/* next token starts a decl? */
+static bool
+isdecltok(struct comp *cm)
+{
+ struct token tk;
+ if (peek(cm, &tk) == TKIDENT) {
+ struct decl *decl = finddecl(cm, tk.name);
+ return decl && decl->scls == SCTYPEDEF;
+ } else {
+ static const bool kws[] = {
+#define kw(x) [TKW##x-TKWBEGIN_] = 1
+ kw(auto), kw(extern), kw(static), kw(register), kw(typedef),
+ kw(_Thread_local), kw(thread_local), kw(_Static_assert),
+ kw(inline), kw(_Noreturn),
+ kw(const), kw(volatile), kw(restrict), kw(_Atomic),
+ kw(void), kw(float), kw(double), kw(_Complex),
+ kw(signed), kw(unsigned), kw(short), kw(long),
+ kw(int), kw(char), kw(_Bool), kw(bool),
+ kw(struct), kw(union), kw(enum),
+ kw(__typeof__), kw(typeof), kw(typeof_unqual),
+ kw(__attribute__)
+#undef kw
+ };
+ return ((uint)tk.t-TKWBEGIN_) < countof(kws) && kws[tk.t-TKWBEGIN_];
+ }
+}
+
+/* next token starts an expr? */
+static bool
+isexprtok(struct comp *cm)
+{
+ struct token tk;
+ if (peek(cm, &tk) == TKIDENT) {
+ struct decl *decl = finddecl(cm, tk.name);
+ return !decl || decl->scls != SCTYPEDEF;
+ } else {
+ static const bool tks[] = {
+#define tk(x) [x] = 1
+ tk('+'), tk('-'), tk('*'), tk('&'), tk('~'), tk('!'), tk(TKINC), tk(TKDEC),
+ tk(TKWsizeof), tk(TKW_Alignof), tk(TKWalignof), tk(TKWtrue), tk(TKWfalse),
+ tk('('), tk(TKNUMLIT), tk(TKCHRLIT), tk(TKSTRLIT), tk(TKW_Generic)
+#undef tk
+ };
+ return tk.t < countof(tks) && tks[tk.t];
+ }
+}
+
+/**********************************/
+/* Environment (scope) management */
+/**********************************/
+
+struct envdecls declsbuf;
+struct tagged { /* a tagged type declaration */
+ union type ty;
+ struct span span;
+};
+static struct tagged envtaggedbuf[1<<7];
+static vec_of(struct tagged) envtagged = VINIT(envtaggedbuf, countof(envtaggedbuf));
+struct env {
+ struct env *up;
+ /* list of decls is implicitly envdecls[decl..ndecl] */
+ ushort decl, ndecl;
+ /* ditto for envtagged[] */
+ ushort tagged, ntagged;
+};
+/* use a hashmap for lookups of top-level declarations, since there's usually many of those */
+static pmap_of(ushort) tldeclmap;
+
+static void
+envdown(struct comp *cm, struct env *e)
+{
+ assert(cm->env->decl + cm->env->ndecl == declsbuf.n);
+ assert(cm->env->tagged + cm->env->ntagged == envtagged.n);
+ e->decl = declsbuf.n;
+ e->tagged = envtagged.n;
+ e->ndecl = e->ntagged = 0;
+ e->up = cm->env;
+ cm->env = e;
+}
+
+static void
+envup(struct comp *cm)
+{
+ struct env *env = cm->env;
+ assert(env->decl + env->ndecl == declsbuf.n);
+ declsbuf.n -= env->ndecl;
+ envtagged.n -= env->ntagged;
+ assert(env->up);
+ cm->env = env->up;
+}
+
+int
+envadddecl(struct env *env, const struct decl *d)
+{
+ assert(env->decl + env->ndecl == declsbuf.n);
+ vpush(&declsbuf, *d);
+ assert(declsbuf.n < 1<<16);
+ ++env->ndecl;
+ if (!env->up) pmap_set(&tldeclmap, d->name, declsbuf.n-1);
+ return declsbuf.n - 1;
+}
+
+/* iters in reversed order of insertion (most to least recent) */
+/* use like so: for (d = NULL; enviterdecl(&d, env);) ... */
+static inline bool
+enviterdecl(struct decl **d, struct env *env)
+{
+ if (!env->ndecl) return 0;
+ if (!*d) *d = &declsbuf.p[env->decl + env->ndecl - 1];
+ else if (*d == &declsbuf.p[env->decl]) return 0;
+ else --*d;
+ return 1;
+}
+
+static struct tagged *
+envaddtagged(struct env *env, union type ty, const struct span *span)
+{
+ struct tagged tagged = { ty, *span };
+ assert(env->tagged + env->ntagged == envtagged.n);
+ vpush(&envtagged, tagged);
+ assert(envtagged.n < 1<<16);
+ ++env->ntagged;
+ return &envtagged.p[envtagged.n - 1];
+}
+
+/* like enviterdecl */
+static inline bool
+envitertagged(struct tagged **l, struct env *env)
+{
+ if (!env->ntagged) return 0;
+ if (!*l) *l = &envtagged.p[env->tagged + env->ntagged - 1];
+ else if (*l == &envtagged.p[env->tagged]) return 0;
+ else --*l;
+ return 1;
+}
+
+static bool
+redeclarationok(const struct decl *old, const struct decl *new)
+{
+ bool takeoldscls = 0;
+ if (old->scls != new->scls) {
+ if (old->scls == SCSTATIC && (new->scls &~ SCEXTERN) == SCNONE && old->ty.t == TYFUNC && new->ty.t == TYFUNC)
+ takeoldscls = 1;
+ else
+ return 0;
+ }
+ switch (old->scls) {
+ case SCSTATIC:
+ case SCEXTERN:
+ if (old->ty.bits == new->ty.bits) goto OkFuncs;
+ if (old->ty.t != new->ty.t) return 0;
+ if (old->ty.t == TYARRAY /* allow 'int x[]; int x[100];' */
+ && typechild(old->ty).bits == typechild(new->ty).bits
+ && (isincomplete(old->ty) || isincomplete(new->ty)))
+ {
+ return 1;
+ }
+ if (old->ty.t == TYFUNC /* allow 'int f(); int f(int);' (some K&R) */
+ && typedata[old->ty.dat].ret.bits == typedata[new->ty.dat].ret.bits
+ && (typedata[old->ty.dat].kandr || typedata[new->ty.dat].kandr))
+ { OkFuncs:
+ if (takeoldscls) ((struct decl *)new)->scls = old->scls;
+ return 1;
+ }
+ return 0;
+ case SCTYPEDEF:
+ return old->ty.bits == new->ty.bits;
+ }
+ return 0;
+}
+
+static int
+putdecl(struct comp *cm, const struct decl *decl)
+{
+ for (struct env *env = cm->env; env; env = env->up) {
+ struct decl *l;
+ if (!env->up) {
+ ushort *pi = pmap_get(&tldeclmap, decl->name);
+ if (pi) {
+ l = &declsbuf.p[*pi];
+ goto Match;
+ }
+ } else for (l = NULL; enviterdecl(&l, env);) {
+ if (decl->name == l->name) {
+ Match:
+ if ((cm->env->up != NULL && decl->scls == SCSTATIC) || (l->isdef && decl->isdef)) {
+ error(&decl->span, "redefinition of '%s'", decl->name);
+ note(&l->span, "previously defined here");
+ break;
+ } else if (!redeclarationok(l, decl)) {
+ error(&decl->span, "incompatible redeclaration of '%s'", decl->name);
+ note(&l->span, "previously declared here");
+ break;
+ }
+ if (l->isdef && !decl->isdef) return l - declsbuf.p;
+ break;
+ }
+ }
+ if (decl->scls != SCEXTERN) break;
+ }
+ return envadddecl(cm->env, decl);
+}
+
+static struct decl *
+finddecl(struct comp *cm, internstr name)
+{
+ assert(name);
+ for (struct env *e = cm->env; e; e = e->up) {
+ if (!e->up) {
+ ushort *pi = pmap_get(&tldeclmap, name);
+ if (pi) return &declsbuf.p[*pi];
+ } else for (struct decl *l = NULL; enviterdecl(&l, e);) {
+ if (name == l->name)
+ return l;
+ }
+ }
+ return NULL;
+}
+
+static union type
+gettagged(struct comp *cm, struct span *span, enum typetag tt, internstr name, bool dodef)
+{
+ struct typedata td = {0};
+ assert(name);
+ for (struct env *e = cm->env; e; e = e->up) {
+ for (struct tagged *l = NULL; envitertagged(&l, e);) {
+ if (name == ttypenames[typedata[l->ty.dat].id]) {
+ if (dodef && e != cm->env)
+ goto Break2;
+ *span = l->span;
+ return l->ty;
+ }
+ }
+ }
+ if (tt == TYENUM && ccopt.pedant) {
+ warn(span, "forward-declared enum is an extension");
+ }
+Break2:
+ td.t = tt;
+ return envaddtagged(cm->env, mktagtype(name, &td), span)->ty;
+}
+
+static union type
+deftagged(struct comp *cm, struct span *span, enum typetag tt, internstr name, union type ty)
+{
+ struct typedata td = {0};
+ assert(name);
+ for (struct tagged *l = NULL; envitertagged(&l, cm->env);) {
+ if (name == ttypenames[typedata[l->ty.dat].id]) {
+ *span = l->span;
+ return l->ty;
+ }
+ }
+ td.t = tt;
+ return envaddtagged(cm->env, ty.t ? ty : mktagtype(name, &td), span)->ty;
+}
+
+/*********************/
+/* Expr Typechecking */
+/*********************/
+
+#define iszero(ex) ((ex).t == ENUMLIT && isint((ex).ty) && (ex).u == 0)
+
+static bool
+islvalue(const struct expr *ex)
+{
+ if (ex->t == EGETF) return islvalue(ex->sub);
+ return ex->t == ESYM || ex->t == EDEREF || ex->t == EINIT || ex->t == ESTRLIT;
+}
+
+static union type /* 6.5.2.6 default argument promotions */
+argpromote(union type t)
+{
+ if (isint(t)) t.t = intpromote(t.t);
+ else if (t.t == TYFLOAT) t.t = TYDOUBLE;
+ else if (t.t == TYARRAY) return mkptrtype(typechild(t), t.flag & TFCHLDQUAL);
+ else if (t.t == TYFUNC) return mkptrtype(t, 0);
+ return t;
+}
+
+bool
+assigncheck(union type t, const struct expr *src)
+{
+ union type srcty = typedecay(src->ty);;
+ if (assigncompat(t, srcty)) {
+ if (t.t == TYPTR && srcty.t == TYPTR
+ && (t.flag & TFCHLDQUAL & srcty.flag & TFCHLDQUAL) != (srcty.flag & TFCHLDQUAL)) {
+ warn(&src->span, "usage of '%ty' discards pointer qualifiers", src->ty);
+ }
+ return 1;
+ } else if (t.t == TYPTR && srcty.t == TYPTR) {
+ warn(&src->span, "converting between incompatible pointer types ('%ty' -> '%ty')", srcty, t);
+ return 1;
+ } else if (t.t == TYPTR && iszero(*src)) return 1;
+ return 0;
+}
+
+static bool
+initcheck(union type t, const struct expr *src)
+{
+ if (assigncheck(t, src)) return 1;
+ if (t.bits == src->ty.bits && (src->t == EINIT || src->t == ESTRLIT)) return 1;
+ return 0;
+}
+
+static void
+incdeccheck(enum toktag tt, const struct expr *ex, const struct span *span)
+{
+ if (!isscalar(ex->ty))
+ error(&ex->span, "invalid operand to %tt '%ty'", tt, ex->ty);
+ else if (!islvalue(ex))
+ error(&ex->span, "operand to %tt is not an lvalue", tt);
+ else if (ex->ty.t == TYPTR && isincomplete(typechild(ex->ty)))
+ error(span, "arithmetic on pointer to incomplete type '%ty'", ex->ty);
+ else if (ex->ty.t == TYPTR && typechild(ex->ty).t == TYFUNC)
+ error(span, "arithmetic on function pointer '%ty'", ex->ty);
+}
+
+static bool /* 6.5.4 Cast operators */
+castcheck(union type to, const struct expr *ex)
+{
+ union type src = ex->ty;
+ if (to.t == TYVOID) return 1;
+ if (isagg(to)) return 0;
+ if (to.bits == src.bits) return 1;
+ if (isarith(to) && isarith(src)) return 1;
+ if (isint(to) && isptrcvt(src)) return 1;
+ if (to.t == TYPTR && isint(src)) return 1;
+ if (to.t == TYPTR && isptrcvt(src)) return 1;
+ return 0;
+}
+
+static union type /* 6.5.2.1 Array subscripting */
+subscriptcheck(const struct expr *ex, const struct expr *rhs, const struct span *span)
+{
+ union type ty;
+ if (ex->ty.t == TYPTR || ex->ty.t == TYARRAY) {
+ if (isincomplete(typedecay(ty = typechild(ex->ty)))) {
+ error(span, "cannot dereference pointer to incomplete type '%ty'", ty);
+ ty = mktype(TYINT);
+ } else if (ty.t == TYFUNC) {
+ error(span, "subscripted value is pointer to function");
+ ty = mktype(TYINT);
+ }
+ } else {
+ error(&ex->span, "subscripted value is not pointer-convertible '%ty'", ex->ty);
+ ty = mktype(TYINT);
+ }
+ if (!isint(rhs->ty))
+ error(&rhs->span, "array subscript is not integer ('%ty')", rhs->ty);
+ return ty;
+}
+
+static uint /* 6.5.3.4 The sizeof and _Alignof operators */
+sizeofalignofcheck(const struct span *span, enum toktag tt, union type ty, const struct expr *ex)
+{
+ uint r = (tt == TKWsizeof ? typesize : typealign)(ty);
+ if (ty.t == TYVOID) {
+ if (ccopt.pedant) warn(span, "applying %'tt to void type", tt);
+ r = 1;
+ } else if (isincomplete(ty)) {
+ error(span, "cannot apply %'tt to incomplete type '%ty'", tt, ty);
+ } else if (ty.t == TYFUNC) {
+ error(span, "cannot apply %'tt to function type '%ty'", tt, ty);
+ } else if (tt == TKWsizeof && ex && ex->t == EGETF && ex->fld.bitsiz) {
+ error(span, "cannot apply %'tt to bitfield", tt);
+ }
+ if (tt != TKWsizeof && ex && ccopt.pedant)
+ warn(span, "%'tt applied to an expression is a GNU extension", tt);
+ return r;
+}
+
+static bool /* 6.5.8 Relational operators */
+relationalcheck(const struct expr *a, const struct expr *b)
+{
+ union type t1 = a->ty, t2 = b->ty;
+ if (isarith(t1) && isarith(t2)) return 1;
+ if (isptrcvt(t1) && isptrcvt(t2)) {
+ t1 = typedecay(t1);
+ t2 = typedecay(t2);
+ return t1.dat == t2.dat;
+ }
+ return 0;
+}
+
+static bool
+isnullpo(const struct expr *ex) /* match '0' or '(void *) 0' */
+{
+ static const union type voidptr = {{ TYPTR, .flag = TFCHLDPRIM, .child = TYVOID }};
+ while (ex->t == ECAST && ex->ty.bits == voidptr.bits)
+ ex = ex->sub;
+ if (iszero(*ex)) return 1;
+ return eval((struct expr *)ex, EVINTCONST) /* GNU extension. should we warn? */
+ && iszero(*ex);
+}
+
+static bool /* 6.5.9 Equality operators */
+equalitycheck(const struct expr *a, const struct expr *b)
+{
+ union type t1 = a->ty, t2 = b->ty;
+ if (isarith(t1) && isarith(t2)) return 1;
+ if (isptrcvt(t1) && isptrcvt(t2)) {
+ t1 = typedecay(t1), t2 = typedecay(t2);
+ /* comparing .dat works for both TFCHLDPRIM and not, (checks equal child types)
+ * quals are ignored either way */
+ return t1.dat == t2.dat || typechild(t1).t == TYVOID || typechild(t2).t == TYVOID;
+ }
+ return (isptrcvt(t1) && isnullpo(b)) || (isptrcvt(t2) && isnullpo(a));
+}
+
+static union type /* 6.5.15 Conditional operator */
+condtype(const struct expr *a, const struct expr *b)
+{
+ union type t1 = typedecay(a->ty), t2 = typedecay(b->ty), s1, s2;
+ if (isarith(t1) && isarith(t2)) return cvtarith(t1, t2);
+ if (t1.bits == t2.bits) return t1;
+ if (t1.t == TYPTR && isnullpo(b)) return t1;
+ if (isnullpo(a) && t2.t == TYPTR) return t2;
+ if (t1.t == TYPTR && t2.t == TYPTR) {
+ s1 = typechild(t1), s2 = typechild(t2);
+ if (s1.bits == s2.bits || s2.t == TYVOID || s1.t == TYVOID) {
+ return mkptrtype(s1.t == TYVOID ? s1 : s2, (t1.flag | t2.flag) & TFCHLDQUAL);
+ }
+ }
+ return mktype(0);
+}
+
+static void
+bintypeerr(const struct span *span, enum toktag tt, union type lhs, union type rhs)
+{
+ error(span, "bad operands to %tt ('%ty', '%ty')", tt, lhs, rhs);
+}
+
+enum binopclass { /* binary operator type-checking classes */
+ BCSET = 1<<7, /* is a (compound) assignment operator? */
+ BCSEQ = 1, BCADDITIVE, BCARITH, BCINT, BCSHFT, BCEQL, BCCMP, BCLOG,
+};
+
+/* table indexed by binary op token;
+ * containing precedence level, expression kind and type-checking class */
+static const struct { uchar prec, t, k; } bintab[] = {
+ ['*'] = {13, EMUL, BCARITH},
+ ['/'] = {13, EDIV, BCARITH},
+ ['%'] = {13, EREM, BCINT},
+ ['+'] = {12, EADD, BCADDITIVE},
+ ['-'] = {12, ESUB, BCADDITIVE},
+ [TKSHL] = {11, ESHL, BCSHFT},
+ [TKSHR] = {11, ESHR, BCSHFT},
+ ['<'] = {10, ELTH, BCCMP},
+ ['>'] = {10, EGTH, BCCMP},
+ [TKLTE] = {10, ELTE, BCCMP},
+ [TKGTE] = {10, EGTE, BCCMP},
+ [TKEQU] = {9, EEQU, BCEQL},
+ [TKNEQ] = {9, ENEQ, BCEQL},
+ ['&'] = {8, EBAND, BCINT},
+ ['^'] = {7, EXOR, BCINT},
+ ['|'] = {6, EBIOR, BCINT},
+ [TKLOGAND] = {5, ELOGAND, BCLOG},
+ [TKLOGIOR] = {4, ELOGIOR, BCLOG},
+ ['?'] = {3, ECOND}, /* not actually a binop (special cased) */
+ ['='] = {2, ESET, BCSET},
+ [TKSETADD] = {2, ESETADD, BCSET|BCADDITIVE}, [TKSETSUB] = {2, ESETSUB, BCSET|BCADDITIVE},
+ [TKSETMUL] = {2, ESETMUL, BCSET|BCARITH}, [TKSETDIV] = {2, ESETDIV, BCSET|BCARITH},
+ [TKSETREM] = {2, ESETREM, BCSET|BCINT}, [TKSETAND] = {2, ESETAND, BCSET|BCINT},
+ [TKSETIOR] = {2, ESETIOR, BCSET|BCINT}, [TKSETXOR] = {2, ESETXOR, BCSET|BCINT},
+ [TKSETSHL] = {2, ESETSHL, BCSET|BCSHFT}, [TKSETSHR] = {2, ESETSHR, BCSET|BCSHFT},
+ [','] = {1, ESEQ, BCSEQ}
+};
+
+static union type
+bintypecheck(const struct span *span, enum toktag tt, struct expr *lhs, struct expr *rhs)
+{
+ enum binopclass k = bintab[tt].k;
+ union type ty = lhs->ty;
+
+ assert(k);
+ if (k & BCSET) {
+ if (!islvalue(lhs))
+ error(&lhs->span, "left-hand-side of assignment is not an lvalue");
+ else if (lhs->qual & QCONST)
+ error(&lhs->span, "cannot assign to const-qualified lvalue (%tq)", ty, lhs->qual);
+ else if (isincomplete(ty))
+ error(&lhs->span, "cannot assign to incomplete type '%ty'", ty);
+ else if (ty.t == TYARRAY)
+ error(&lhs->span, "cannot assign to array type '%ty'", ty);
+ else if (ty.t == TYFUNC)
+ error(&lhs->span, "cannot assign to function designator '%ty'", lhs->ty);
+ }
+ switch (k &~ BCSET) {
+ case 0:
+ if (isagg(ty) && !(lhs->qual & QCONST) && typedata[ty.dat].anyconst)
+ error(&lhs->span, "cannot assign to aggregate with const-qualified member");
+ if (!assigncheck(ty, rhs))
+ goto Error;
+ break;
+ case BCSEQ:
+ ty = rhs->ty;
+ break;
+ case BCADDITIVE:
+ if (tt == '+' && isptrcvt(rhs->ty)) {
+ /* int + ptr -> ptr + int (for convenience) */
+ const struct expr swaptmp = *lhs;
+ *lhs = *rhs;
+ *rhs = swaptmp;
+ ty = lhs->ty;
+ }
+ if (isarith(ty) && isarith(rhs->ty)) {
+ /* num +/- num */
+ ty = cvtarith(ty, rhs->ty);
+ assert(ty.t);
+ } else if ((ty.t == TYPTR || ty.t == TYARRAY) && isint(rhs->ty)) {
+ /* ptr +/- int */
+ union type pointee = typechild(ty);
+ if (isincomplete(pointee))
+ error(span, "arithmetic on pointer to incomplete type '%ty'", ty);
+ else if (pointee.t == TYFUNC)
+ error(span, "arithmetic on function pointer '%ty'", ty);
+ ty = typedecay(ty);
+ } else if (tt == '-' && isptrcvt(ty) && isptrcvt(rhs->ty)) {
+ /* ptr - ptr */
+ union type pointee1 = typechild(typedecay(ty)),
+ pointee2 = typechild(typedecay(rhs->ty));
+ if (isincomplete(pointee1))
+ error(span, "arithmetic on pointer to incomplete type '%ty'", ty);
+ else if (pointee1.t == TYFUNC)
+ error(span, "arithmetic on function pointer '%ty'", lhs->ty);
+ else if (pointee1.bits != pointee2.bits) {
+ error(span, "arithmetic on incompatible pointer types: '%ty', '%ty'",
+ ty, rhs->ty);
+ }
+ ty = mktype(targ_ptrdifftype);
+ } else goto Error;
+ break;
+ case BCARITH:
+ ty = cvtarith(ty, rhs->ty);
+ if (!ty.t) {
+ ty.t = TYINT;
+ Error:
+ bintypeerr(span, tt, lhs->ty, rhs->ty);
+ }
+ break;
+ case BCINT:
+ if (!isint(ty) || !isint(rhs->ty))
+ goto Error;
+ ty = cvtarith(ty, rhs->ty);
+ assert(ty.t);
+ break;
+ case BCSHFT: /* 6.5.7 Bitwise shift operators */
+ if (!isint(ty) || !isint(rhs->ty)) {
+ ty = mktype(TYINT);
+ goto Error;
+ }
+ ty.t = intpromote(ty.t);
+ assert(ty.t);
+ break;
+ case BCEQL:
+ ty = mktype(TYINT);
+ if (!equalitycheck(lhs, rhs)) {
+ if (isptrcvt(lhs->ty) && isptrcvt(rhs->ty))
+ warn(span, "comparison of distinct pointer types ('%ty' and '%ty')", lhs->ty, rhs->ty);
+ else
+ goto Error;
+ }
+ break;
+ case BCCMP:
+ ty = mktype(TYINT);
+ if (!relationalcheck(lhs, rhs)) {
+ if (isptrcvt(lhs->ty) && isptrcvt(rhs->ty))
+ warn(span, "comparison of distinct pointer types ('%ty' and '%ty')", lhs->ty, rhs->ty);
+ else
+ goto Error;
+ }
+ break;
+ case BCLOG: /* 6.5.13-14 Logical AND/OR operator */
+ ty = mktype(TYINT);
+ if (!isscalar(typedecay(ty)) || !isscalar(typedecay(rhs->ty)))
+ goto Error;
+ break;
+ }
+ return (k & BCSET) || !ty.t ? lhs->ty : ty;
+}
+
+/****************/
+/* Expr Parsing */
+/****************/
+
+#define mkexpr(t_,span_,ty_,...) ((struct expr){.t=(t_), .ty=(ty_), .span=(span_), __VA_ARGS__})
+
+static struct expr *
+exprdup(struct comp *cm, const struct expr *e)
+{
+ return alloccopy(&cm->exarena, e, sizeof *e, 0);
+}
+static struct expr *
+exprdup2(struct comp *cm, const struct expr *e1, const struct expr *e2)
+{
+ struct expr *r = alloc(&cm->exarena, 2*sizeof *r, 0);
+ r[0] = *e1, r[1] = *e2;
+ return r;
+}
+
+static struct expr expr(struct comp *cm);
+static struct expr commaexpr(struct comp *cm);
+
+enum { IMPLICITSYMTY = 0xFF, };
+
+static struct expr /* 6.5.2.2 Function calls */
+callexpr(struct comp *cm, const struct span *span_, const struct expr *callee)
+{
+ struct token tk;
+ struct expr ex, arg;
+ struct span span = callee->span;
+ union type ty = callee->ty;
+ const struct typedata *td = NULL;
+ struct expr argbuf[10];
+ vec_of(struct expr) args = VINIT(argbuf, countof(argbuf));
+ bool spanok = joinspan(&span.ex, span_->ex);
+ bool printsig = 0;
+ const struct builtin *builtin = NULL;
+
+ if (callee->t == ESYM && !callee->ty.t && declsbuf.p[callee->decl].isbuiltin) {
+ builtin = declsbuf.p[callee->decl].builtin;
+ assert(!ty.t);
+ }
+
+ if (callee->t == ESYM && ty.t == IMPLICITSYMTY) { /* implicit function decl.. */
+ internstr name = callee->implicitsym;
+ struct decl decl = {
+ (ty = mkfntype(mktype(TYINT), 0, NULL, /* kandr */ 1, 0)),
+ .scls = SCEXTERN, .span = span, .name = name, .sym = name
+ };
+ warn(&span, "call to undeclared function '%s'", name);
+ ((struct expr *)callee)->ty = decl.ty;
+ ((struct expr *)callee)->decl = putdecl(cm, &decl);
+ }
+
+ if (!builtin) {
+ if (ty.t == TYPTR) /* auto-deref when calling a function pointer */
+ ty = typechild(ty);
+ if (ty.t != TYFUNC)
+ error(&span, "calling a value of type '%ty'", callee->ty);
+ else
+ td = &typedata[ty.dat];
+ if (ty.t == TYFUNC && td->ret.t != TYVOID && isincomplete(td->ret))
+ error(&span, "cannot call function with incomplete return type '%ty'", td->ret);
+ }
+
+ if (!match(cm, &tk, ')')) for (;;) {
+ arg = expr(cm);
+ spanok = spanok && joinspan(&span.ex, callee->span.ex);
+ if (td && args.n == td->nmemb && !td->variadic && !td->kandr) {
+ error(&arg.span, "too many args to function taking %d params", td->nmemb);
+ printsig = 1;
+ }
+ if (arg.ty.t == TYVOID) {
+ error(&arg.span, "invalid use of void expression");
+ } else if (td && args.n < td->nmemb && !td->kandr) {
+ if (!assigncheck(td->param[args.n], &arg)) {
+ error(&arg.span, "arg #%d of type '%ty' is incompatible with '%ty'",
+ args.n+1, arg.ty, td->param[args.n]);
+ printsig = 1;
+ }
+ }
+ vpush(&args, arg);
+ peek(cm, &tk);
+ if (match(cm, &tk, ',')) {
+ spanok = spanok && joinspan(&span.ex, tk.span.ex);
+ } else if (expect(cm, ')', "or ',' after arg")) {
+ break;
+ }
+ }
+ if (!spanok || !joinspan(&span.ex, tk.span.ex)) span = *span_;
+
+ if (td && !td->variadic && !td->kandr && args.n < td->nmemb) {
+ error(&tk.span, "not enough args to function taking %d param%s",
+ td->nmemb, td->nmemb != 1 ? "s" : "");
+ printsig = 1;
+ }
+ if (printsig) note(&callee->span, "function signature is '%ty'", ty);
+
+ ex = mkexpr(ECALL, span, ty.t == TYFUNC ? td->ret : ty, .narg = args.n,
+ .sub = alloc(&cm->exarena, (args.n+1)*sizeof(struct expr), 0));
+ ex.sub[0] = *callee;
+ memcpy(ex.sub+1, args.p, args.n*sizeof(struct expr));
+ vfree(&args);
+ if (builtin) {
+ builtin->sema(cm, &ex);
+ }
+ return ex;
+}
+
+static void
+ppostfixopers(struct comp *cm, struct expr *ex)
+{
+ struct expr tmp, rhs;
+ struct token tk, tk2;
+ struct span span;
+ union type ty;
+
+ for (;;) switch (peek(cm, &tk)) {
+ default: return;
+ case TKINC:
+ case TKDEC:
+ lex(cm, &tk);
+ span = ex->span;
+ if (!joinspan(&span.ex, tk.span.ex)) span = tk.span;
+ incdeccheck(tk.t, ex, &span);
+ *ex = mkexpr(tk.t == TKINC ? EPOSTINC : EPOSTDEC, span, ex->ty, .sub = exprdup(cm, ex));
+ continue;
+ case '[': /* a[subscript] */
+ lex(cm, NULL);
+ rhs = commaexpr(cm);
+ span = ex->span;
+ if (!joinspan(&span.ex, tk.span.ex) || !joinspan(&span.ex, ex->span.ex)
+ || (peek(cm, &tk), !joinspan(&span.ex, tk.span.ex)))
+ span = tk.span;
+ expect(cm, ']', NULL);
+
+ if (isint(ex->ty) && isptrcvt(rhs.ty)) {
+ /* swap idx[ptr] -> ptr[idx] */
+ tmp = *ex;
+ *ex = rhs;
+ rhs = tmp;
+ }
+
+ ty = subscriptcheck(ex, &rhs, &span);
+ assert(ty.t);
+ if (!iszero(rhs)) {
+ tmp.sub = exprdup2(cm, ex, &rhs);
+ tmp.t = EADD;
+ tmp.span = span;
+ tmp.ty = typedecay(ex->ty);
+ }
+ tmp.sub = exprdup(cm, iszero(rhs) ? ex : &tmp);
+ tmp.span = span;
+ tmp.t = EDEREF;
+ tmp.qual = ex->ty.flag & TFCHLDQUAL;
+ tmp.ty = ty;
+ *ex = tmp;
+ continue;
+ case '(': /* call(args) */
+ lex(cm, &tk);
+ span = ex->span;
+ *ex = callexpr(cm, &span, ex);
+ continue;
+ case TKARROW:
+ if (ex->ty.t != TYPTR && ex->ty.t != TYARRAY)
+ error(&ex->span, "operand to -> is not a pointer: '%ty'", ex->ty);
+ else
+ *ex = mkexpr(EDEREF, ex->span, typechild(ex->ty), .qual = ex->ty.flag & TFCHLDQUAL,
+ .sub = exprdup(cm, ex));
+ /* fallthru */
+ case '.':
+ lex(cm, &tk);
+ span = ex->span;
+ peek(cm, &tk2); /* field name */
+ if (!expect(cm, TKIDENT, NULL)) tk2.s = "";
+ if (!joinspan(&span.ex, tk.span.ex) || !joinspan(&span.ex, tk2.span.ex))
+ span = tk.span;
+ if (!isagg(ex->ty)) {
+ error(&span, "member access operand is not an aggregate: '%ty'%s", ex->ty,
+ ex->ty.t == TYPTR && isagg(typechild(ex->ty)) ? "; did you mean to use '->'?" : "");
+ } else {
+ struct fielddata fld = {.t = mktype(TYINT)};
+ if (*tk2.s && !getfield(&fld, ex->ty, tk2.name))
+ error(&span, "'%ty' has no such field: '%s'", ex->ty, tk2.name);
+ if (ex->t == EGETF && ex->qual == fld.qual) { /* accumulate */
+ ex->span = span;
+ ex->ty = fld.t;
+ ex->fld.off += fld.off;
+ ex->fld.bitoff = fld.bitoff;
+ ex->fld.bitsiz = fld.bitsiz;
+ } else {
+ *ex = mkexpr(EGETF, span, fld.t, .qual = ex->qual | fld.qual, .sub = exprdup(cm, ex),
+ .fld = { fld.off, fld.bitsiz, fld.bitoff });
+ }
+ }
+ continue;
+ }
+}
+
+static struct expr
+vaargexpr(struct comp *cm, struct span *span)
+{
+ struct token tk;
+ struct expr ex = mkexpr(EXXX, *span, mktype(TYVOID), );
+ if (expect(cm, '(', "after __builtin_va_arg")) {
+ struct expr arg = expr(cm);
+ struct decl decl;
+ union type ty;
+ expect(cm, ',', NULL);
+ decl = pdecl(&(struct declstate){DCASTEXPR}, cm);
+ ty = decl.ty;
+ peek(cm, &tk);
+ if (expect(cm, ')', NULL))
+ joinspan(&span->ex, tk.span.ex);
+ if (ty.t == TYARRAY)
+ warn(&decl.span, "va_arg type argument is array type '%ty', which is undefined behavior", decl.ty);
+ else if (ty.t == TYFUNC)
+ error(&decl.span, "va_arg type argument is function type '%ty'", decl.ty);
+ else {
+ ty = argpromote(ty);
+ if (ty.bits != decl.ty.bits) {
+ warn(&decl.span,
+ "va_arg type argument is promotable type '%ty', which has undefined behavior"
+ " (it will be promoted to '%ty')", decl.ty, ty);
+ }
+ }
+ ex = mkexpr(EVAARG, *span, decl.ty, .sub = exprdup(cm, &arg));
+ }
+ return ex;
+}
+
+static struct expr
+genericexpr(struct comp *cm, struct span *span)
+{
+ struct token tk;
+ if (expect(cm, '(', "after _Generic")) {
+ struct expr control = expr(cm), dfault = {0}, ex = {0};
+ expect(cm, ',', NULL);
+ for (;;) {
+ if (match(cm, &tk, TKWdefault)) {
+ expect(cm, ':', NULL);
+ if (dfault.t) {
+ error(&tk.span, "duplicate 'default' specifier in generic selection expression");
+ (void)expr(cm);
+ } else {
+ dfault = expr(cm);
+ }
+ } else {
+ struct decl decl = pdecl(&(struct declstate){DCASTEXPR}, cm);
+ union type ty = decl.ty;
+ expect(cm, ':', NULL);
+ if (!ex.t &&
+ (typedecay(ty).bits == typedecay(control.ty).bits
+ || ((ty.t == TYENUM || control.ty.t == TYENUM) && scalartypet(ty) == scalartypet(control.ty))))
+ ex = expr(cm);
+ else
+ (void)expr(cm);
+ }
+ if (match(cm, &tk, ')')) break;
+ else if (!expect(cm, ',', "or `)'")) {
+ if (!isdecltok(cm)) {
+ peek(cm, &tk); /* want the span */
+ break;
+ }
+ }
+ }
+ if (!ex.t) ex = dfault;
+ if (!ex.t) {
+ error(&control.span,
+ "controlling type '%ty' not compatible with any generic association type",
+ control.ty);
+ ex.ty.t = TYINT;
+ }
+ ex.span = *span;
+ joinspan(&ex.span.ex, tk.span.ex);
+ return ex;
+ }
+ return mkexpr(ENUMLIT,*span,mktype(TYINT),);
+}
+
+static inline int
+tkprec(int tt)
+{
+ return ((uint)tt < countof(bintab)) ? bintab[tt].prec : 0;
+}
+
+static struct expr initializer(struct comp *cm, union type *ty, enum evalmode ev,
+ bool globl, enum qualifier qual, internstr name);
+
+static internstr istr__func__, istr_main, istr_memset;
+
+static internstr mkhiddensym(const char *fnname, const char *name, int id);
+
+/* parse an expression with the given operator precedence */
+/* param ident is a kludge to support block labels without backtracking or extra lookahead
+ * see stmt() */
+enum exprctx { EFROMSTMT = 1, EARRAYCOUNT, EATTRARG };
+static struct expr
+exprparse(struct comp *cm, int prec, const struct token *ident, enum exprctx ctx)
+{
+ struct token tk;
+ struct span span;
+ struct expr ex;
+ union type ty;
+ struct {
+ struct span span;
+ union {
+ union type ty; /* cast type */
+ struct {
+ uchar t0; /* t == 0 */
+ short tt; /* token */
+ };
+ };
+ } unops[4];
+ int nunop = 0;
+
+ if (ident) {
+ assert(ident->t == TKIDENT);
+ tk = *ident;
+ ident = NULL;
+ goto Ident;
+ }
+
+Unary:
+ switch (lex(cm, &tk)) {
+ /* unary operators (gather) */
+ case '*':
+ if (ctx == EARRAYCOUNT && peek(cm, NULL) == ']') {
+ /* kludge for C99 `int x[*]` (unk VLA size) */
+ return (struct expr) { 0, .span = tk.span };
+ }
+ /* fallthru */
+ case '+': case '-': case '~': case '!':
+ case '&': case TKINC: case TKDEC:
+ Unops:
+ unops[nunop].span = tk.span;
+ unops[nunop].t0 = 0;
+ unops[nunop].tt = tk.t;
+ if (++nunop >= countof(unops)) {
+ ex = exprparse(cm, 999, NULL, 0);
+ break;
+ }
+ goto Unary;
+
+ /* might be unary op (cast) or primary expr */
+ case '(':
+ if (!isdecltok(cm)) { /* (expr) */
+ struct span span = tk.span;
+ ex = commaexpr(cm);
+ joinspan(&span.ex, ex.span.ex);
+ peek(cm, &tk);
+ if (expect(cm, ')', NULL)) joinspan(&span.ex, tk.span.ex);
+ ex.span = span;
+ } else { /* (type) expr */
+ struct declstate st = { DCASTEXPR };
+ struct decl decl = pdecl(&st, cm);
+ struct span span = tk.span;
+ assert(decl.ty.t);
+ peek(cm, &tk);
+ if (expect(cm, ')', NULL))
+ joinspan(&span.ex, tk.span.ex);
+ if (peek(cm, NULL) == '{') {
+ if (ccopt.cstd < STDC99)
+ warn(&tk.span, "compound literals are a c99 feature");
+ ex = initializer(cm, &decl.ty, (decl.scls & SCSTATIC) ? EVSTATICINI : EVFOLD,
+ /* globl */ 0, decl.qual, NULL);
+ break;
+ }
+ unops[nunop].span = span;
+ unops[nunop].ty = decl.ty;
+ if (++nunop >= countof(unops)) {
+ ex = exprparse(cm, 999, NULL, 0);
+ break;
+ }
+ goto Unary;
+ }
+ break;
+ /* base exprs */
+ case TKNUMLIT:
+ case TKCHRLIT:
+ ex = mkexpr(ENUMLIT, tk.span, mktype(0), );
+ if (!(ty.t = parsenumlit(&ex.u, &ex.f, &tk, 0)))
+ error(&tk.span, "bad %s literal %'tk", tk.t == TKNUMLIT ? "number" : "character", &tk);
+ ex.ty.t = ty.t ? ty.t : TYINT;
+ break;
+ case TKWtrue: case TKWfalse:
+ ex = mkexpr(ENUMLIT, tk.span, mktype(TYBOOL), .u = tk.t == TKWtrue);
+ break;
+ case TKSTRLIT:
+ ty = mktype(((const char []){TYCHAR, TYSHORT, TYINT})[tk.wide]);
+ ex = mkexpr(ESTRLIT, tk.span, mkarrtype(ty, 0, tk.len+1), { .s.p = (void *)tk.s, .s.n = tk.len });
+ break;
+ case TKIDENT: Ident: {
+ struct decl *decl = finddecl(cm, tk.name);
+ if (!decl) {
+ if (cm->env->up && tk.name->c == '_'
+ && (!strcmp(&tk.name->c, "__FUNCTION__") || !strcmp(&tk.name->c, "__PRETTY_FUNCTION__"))) {
+ /* hack: treat these identifiers as __func__ synonym to support the GNU extension */
+ warn(&tk.span, "%'tk is a GNU extension", &tk);
+ decl = finddecl(cm, istr__func__);
+ assert(decl && decl->scls == SCSTATIC);
+ goto Sym;
+ } else if (ctx == EATTRARG && nunop == 0 && (peek(cm, NULL) == ',' || peek(cm, NULL) == ')')) {
+ return ex = mkexpr(ESYM, tk.span, mktype(IMPLICITSYMTY), .implicitsym = tk.name);
+ } else if (peek(cm, NULL) == '(') { /* implicit function decl? */
+ ex = mkexpr(ESYM, tk.span, mktype(IMPLICITSYMTY), .implicitsym = tk.name);
+ } else {
+ error(&tk.span, "undeclared identifier %'tk", &tk);
+ ex = mkexpr(ESYM, tk.span, mktype(TYINT), .implicitsym = NULL);
+ }
+ } else if (decl->scls == SCTYPEDEF) {
+ error(&tk.span, "unexpected typename %'tk (expected expression)", &tk);
+ ex = mkexpr(ESYM, tk.span, decl->ty, .implicitsym = NULL);
+ } else if (decl->isenum) {
+ ex = mkexpr(ENUMLIT, tk.span, decl->ty, .i = decl->value);
+ } else Sym: {
+ if (decl->name == istr__func__ && decl->isbuiltin) { /* lazy __func__ */
+ internstr fnname = decl->sym;
+ decl->isbuiltin = 0;
+ decl->sym = mkhiddensym(&fnname->c, "__func__", 1);
+ uint off = objnewdat(decl->sym, objout.code ? Stext : Srodata, 0, typesize(decl->ty), typealign(decl->ty));
+ uchar *p = objout.code ? objout.textbegin + off : objout.rodata.p + off;
+ memcpy(p, fnname, typearrlen(decl->ty)-1);
+ }
+ ex = mkexpr(ESYM, tk.span, decl->ty, .qual = decl->qual, .decl = decl - declsbuf.p);
+ }
+ break; }
+ case TKWsizeof: case TKW_Alignof: case TKWalignof: {
+ enum toktag tt = tk.t;
+ uint res;
+ span = tk.span;
+ if (!match(cm, NULL, '(')) /* sizeof/alignof expr */
+ goto Unops;
+ else if (isdecltok(cm)) { /* sizeof/alignof (type) */
+ struct declstate st = { DCASTEXPR };
+ ty = pdecl(&st, cm).ty;
+ peek(cm, &tk);
+ if (expect(cm, ')', NULL))
+ joinspan(&span.ex, tk.span.ex);
+ res = sizeofalignofcheck(&span, tt, ty, NULL);
+ } else { /* sizeof/alignof expr */
+ struct expr tmp = commaexpr(cm);
+ peek(cm, &tk);
+ if (expect(cm, ')', NULL))
+ joinspan(&span.ex, tk.span.ex);
+ ppostfixopers(cm, &tmp);
+ ty = tmp.ty;
+ res = sizeofalignofcheck(&span, tt, ty, &tmp);
+ }
+ ex = mkexpr(ENUMLIT, span, mktype(targ_sizetype), .u = res);
+ break; }
+ case TKW__builtin_va_arg:
+ span = tk.span;
+ ex = vaargexpr(cm, &span);
+ break;
+ case TKW_Generic:
+ span = tk.span;
+ ex = genericexpr(cm, &span);
+ break;
+ default:
+ fatal(&tk.span, "expected %s (near %'tk)", ctx == EFROMSTMT ? "statement" : "expression", &tk);
+ }
+
+ ppostfixopers(cm, &ex);
+
+ /* unary operators (process) */
+ while (nunop-- > 0) {
+ enum exprkind ek;
+ span = unops[nunop].span;
+ joinspan(&span.ex, ex.span.ex);
+ if (unops[nunop].t0 == 0) {
+ switch (unops[nunop].tt) {
+ case '+':
+ ek = EPLUS;
+ goto Alu;
+ case '-':
+ ek = ENEG;
+ goto Alu;
+ case '~':
+ ek = ECOMPL;
+ goto Alu;
+ case '!':
+ ek = ELOGNOT;
+ Alu:
+ ty = ek == ELOGNOT ? mktype(TYINT) : cvtarith(ex.ty, ex.ty);
+ if (!ty.t || (ek == ECOMPL && !isint(ty))) {
+ error(&tk.span, "invalid operand to %'tk '%ty'", &tk, ex.ty);
+ ty = mktype(TYINT);
+ }
+ ex = mkexpr(ek, span, ty, .sub = exprdup(cm, &ex));
+ break;
+ case TKINC: case TKDEC:
+ ty = ex.ty;
+ incdeccheck(tk.t, &ex, &span);
+ ex = mkexpr(unops[nunop].tt == TKINC ? EPREINC : EPREDEC, span, ty,
+ .sub = exprdup(cm, &ex));
+ break;
+ case '*':
+ if (ex.ty.t == TYPTR || ex.ty.t == TYARRAY) {
+ ty = typechild(ex.ty);
+ if (ty.t != TYVOID && isincomplete(typedecay(ty))) {
+ error(&span, "cannot dereference pointer to incomplete type '%ty'", ty);
+ ty = mktype(TYINT);
+ }
+ } else {
+ error(&span, "invalid operand to unary * '%ty'", ex.ty);
+ ty = mktype(TYINT);
+ }
+ ex = mkexpr(EDEREF, span, ty, .qual = ex.ty.flag & TFCHLDQUAL,
+ .sub = exprdup(cm, &ex));
+ break;
+ case '&':
+ if (!islvalue(&ex))
+ error(&span, "operand to unary & is not an lvalue");
+ if (ex.t == EGETF && ex.fld.bitsiz)
+ error(&span, "cannot take address of bitfield");
+ ex = mkexpr(EADDROF, span, mkptrtype(ex.ty, ex.qual), .sub = exprdup(cm, &ex));
+ break;
+ case TKWsizeof: case TKW_Alignof: case TKWalignof:
+ ex = mkexpr(ENUMLIT, span, mktype(targ_sizetype),
+ .u = sizeofalignofcheck(&span, unops[nunop].tt, ex.ty, &ex));
+ break;
+ default: assert(0);
+ }
+ } else { /* cast */
+ ty = unops[nunop].ty;
+ if (!castcheck(ty, &ex))
+ error(&span, "cannot cast value of type '%ty' to '%ty'", ex.ty, ty);
+ if (ex.t == ENUMLIT && isint(ex.ty) && ty.t == TYPTR)
+ ex.ty = ty;
+ else
+ ex = mkexpr(ECAST, span, ty, .sub = exprdup(cm, &ex));
+ }
+ }
+
+ /* binary operators */
+ for (int opprec; (opprec = tkprec(peek(cm, &tk))) >= prec;) {
+ enum exprkind ek = bintab[tk.t].t;
+ struct expr rhs, tmp;
+ lex(cm, NULL);
+ if (ek != ECOND) {
+ /* only the assignment operators are right-associative */
+ bool leftassoc = (bintab[tk.t].k & BCSET) == 0;
+ /* ex OP rhs */
+ span.sl = tk.span.sl;
+ span.ex = ex.span.ex;
+ rhs = exprparse(cm, opprec + leftassoc, NULL, 0);
+ if (!joinspan(&span.ex, tk.span.ex) || !joinspan(&span.ex, rhs.span.ex))
+ span.ex = tk.span.ex;
+ ty = bintypecheck(&span, tk.t, &ex, &rhs);
+ assert(ty.t);
+ ex = mkexpr(ek, span, ty, .sub = exprdup2(cm, &ex, &rhs));
+ } else {
+ /* logical-OR-expression ? expression : conditional-expression */
+ struct expr *sub;
+ span.sl = tk.span.sl;
+ span.ex = ex.span.ex;
+ if (!isscalar(ex.ty) && !isptrcvt(ex.ty))
+ error(&ex.span, "?: condition is not a scalar type: '%ty'", ex.ty);
+ tmp = commaexpr(cm);
+ joinspan(&tk.span.ex, tmp.span.ex);
+ expect(cm, ':', NULL);
+ rhs = exprparse(cm, opprec, NULL, 0);
+ if (!joinspan(&span.ex, tk.span.ex) || !joinspan(&span.ex, tmp.span.ex)
+ || !joinspan(&span.ex, rhs.span.ex))
+ span.ex = tk.span.ex;
+ ty = condtype(&tmp, &rhs);
+ if (!ty.t) {
+ error(&span, "incompatible types in conditional expression: '%ty', '%ty'", tmp.ty, rhs.ty);
+ ty = tmp.ty;
+ }
+ sub = alloc(&cm->exarena, 3 * sizeof*sub, 0);
+ sub[0] = ex, sub[1] = tmp, sub[2] = rhs;
+ ex = mkexpr(ECOND, span, ty, .sub = sub);
+ }
+ }
+
+ return ex;
+}
+
+static struct expr
+expr(struct comp *cm)
+{
+ return exprparse(cm, bintab['='].prec, NULL, 0); /* non-comma expr */
+}
+
+static struct expr
+arraycountexpr(struct comp *cm)
+{
+ return exprparse(cm, bintab['='].prec, NULL, EARRAYCOUNT); /* non-comma expr, or lone '*' */
+}
+
+static struct expr
+constantexpr(struct comp *cm)
+{
+ return exprparse(cm, bintab['?'].prec, NULL, 0); /* conditional-expr */
+}
+
+static struct expr
+commaexpr(struct comp *cm)
+{
+ return exprparse(cm, 1, NULL, 0);
+}
+
+/****************/
+/* Initializers */
+/****************/
+
+static uint
+nmemb(union type ty)
+{
+ switch (ty.t) {
+ case TYARRAY: return typearrlen(ty) ? typearrlen(ty) : -1u;
+ case TYUNION: case TYSTRUCT: return typedata[ty.dat].nmemb;
+ default: return 1;
+ }
+}
+
+static bool
+objectp(union type ty)
+{
+ return isagg(ty) || ty.t == TYARRAY;
+}
+
+static bool
+chrarrayof(union type ty, union type chld)
+{
+ assert(isint(chld));
+ return ty.t == TYARRAY && isint(typechild(ty)) && typesize(typechild(ty)) == typesize(chld);
+}
+
+static union type
+membertype(uint *off, uint *bitsiz, uint *bitoff, union type ty, uint idx)
+{
+ *bitsiz = *bitoff = 0;
+ if (!objectp(ty)) {
+ *off = 0;
+ return ty;
+ } else if (ty.t == TYARRAY) {
+ *off = typesize(typechild(ty)) * idx;
+ return typechild(ty);
+ } else if (idx < typedata[ty.dat].nmemb) {
+ struct fielddata fld = typedata[ty.dat].fld[idx].f;
+ *off = fld.off;
+ *bitsiz = fld.bitsiz, *bitoff = fld.bitoff;
+ return fld.t;
+ }
+ *off = ~0u;
+ return mktype(0);
+}
+
+struct initparser {
+ struct initcur {
+ union type ty;
+ uint idx;
+ uint off;
+ short prev;
+ } buf[32], *cur, *sub;
+ struct arena **arena;
+ uint arrlen;
+ enum evalmode ev;
+ bool dyn; /* when set, data is written to a temporary buffer first, because either:
+ - size is not known until parsing done (implicit array size)
+ - data section is not known until parsing done (to avoid relocs in .rodata)
+ otherwise write to the corresponding object data section buffer directly */
+ union {
+ struct init *init; /* for initializer with automatic storage */
+ struct { /* for static storage (dyn = 0) */
+ enum section sec;
+ uint off;
+ };
+ struct { /* for static storage (dyn = 1) */
+ vec_of(uchar) ddat;
+ struct dreloc {
+ struct dreloc *link;
+ internstr sym;
+ vlong addend;
+ uint off;
+ } *drel;
+ };
+ };
+};
+
+static void
+excesscheck(struct initparser *ip, const struct span *span)
+{
+ union type sub = ip->sub->ty;
+ uint n = nmemb(sub);
+ if (ip->sub->idx == n) {
+ if (sub.t == TYARRAY)
+ warn(span, "excess elements in array initializer for '%ty'", sub);
+ else if (sub.t == TYSTRUCT)
+ warn(span, "excess elements in initializer; '%ty' has %u member%s", sub, n, &"s"[n==1]);
+ else if (sub.t == TYUNION)
+ warn(span, "excess elements in union initializer");
+ else
+ warn(span, "excess elements in scalar initializer");
+ }
+}
+
+#if 1
+#define dumpini(_)
+#else
+/* debugging */
+static void
+dumpini(struct initparser *ip)
+{
+ efmt(">>>\n");
+ for (struct initcur *s = ip->buf; s < ip->sub+1; ++s) {
+ efmt(" ");
+ efmt("%d. [%ty, %u]", s- ip->buf, s->ty, s->idx);
+ if (s == ip->cur) efmt(" <-- cursor");
+ ioputc(&bstderr, '\n');
+ }
+ efmt("<<<\n");
+}
+#endif
+
+static vlong /* -> returns addend */
+expr2reloc(internstr *psym, const struct expr *ex)
+{
+ if (ex->t == ESSYMREF) {
+ *psym = ex->ssym.sym;
+ return ex->ssym.off;
+ } else if (ex->t == ESTRLIT || ex->t == EINIT) {
+ if (ex->t == ESTRLIT) assert(ex->ty.t == TYARRAY);
+ *psym = xcon2sym(expraddr(NULL, ex).i);
+ return 0;
+ }
+ fatal(&ex->span, "internal bug: non static reloc?");
+}
+
+static bool
+rodatarelocok(void)
+{
+ return !(ccopt.pie | ccopt.pic);
+}
+
+static void
+iniwrite(struct comp *cm, struct initparser *ip, uint off, uint bitsiz, uint bitoff, union type ty, struct expr *ex)
+{
+ if (ex->ty.t == TYSTRUCT && ip->ev == EVSTATICINI) {
+ assert(ty.bits == ex->ty.bits);
+ for (uint i = 0, n = nmemb(ex->ty); i < n; ++i) {
+ uint suboff;
+ union type sub = membertype(&suboff, &bitsiz, &bitoff, ex->ty, i);
+ iniwrite(cm, ip, off + suboff, bitsiz, bitoff, sub, exprdup(cm, &mkexpr(EGETF, ex->span, sub, .sub = ex)));
+ }
+ } else if (ip->ev == EVSTATICINI) {
+ uchar *p;
+ uint siz = typesize(ty);
+ if (nerror) return;
+ if (ip->dyn) {
+ if (ip->ddat.n < off + siz) {
+ uint old = ip->ddat.n;
+ vresize(&ip->ddat, off + siz);
+ memset(ip->ddat.p + old, 0, ip->ddat.n - old);
+ assert(off + siz == ip->ddat.n);
+ }
+ p = ip->ddat.p + off;
+ } else {
+ p = (ip->sec == Sdata ? objout.data.p : objout.rodata.p) + ip->off + off;
+ }
+
+ if (ex->t == ENUMLIT) {
+ struct expr *e = ex, tmp;
+ if (ex->ty.bits != ty.bits && ty.t != TYPTR) {
+ tmp = mkexpr(ECAST, ex->span, ty, .sub = ex);
+ e = &tmp;
+ assert(eval(e, EVSTATICINI));
+ assert(e->t == ENUMLIT);
+ }
+ if (!bitsiz) switch (siz) {
+ default: assert(0);
+ case 1: *p = e->u; break;
+ case 2: wr16targ(p, e->u); break;
+ case 4: isint(ty) ? wr32targ(p, e->u) : wrf32targ(p, e->f); break;
+ case 8: isint(ty) ? wr64targ(p, e->u) : wrf64targ(p, e->f); break;
+ } else {
+ uvlong mask = (bitsiz == 64 ? -1ull : (1ull << bitsiz) - 1) << bitoff;
+ if (bitoff + bitsiz > siz*8) siz <<= 1; /* straddles an allocation boundary */
+ switch (siz) {
+ default: assert(0);
+ case 1: *p = (*p &~ mask) | (e->u << bitoff & mask); break;
+ case 2: wr16targ(p, (rd16targ(p) &~ mask) | (e->u << bitoff & mask)); break;
+ case 4: wr32targ(p, (rd32targ(p) &~ mask) | (e->u << bitoff & mask)); break;
+ case 8: wr64targ(p, (rd64targ(p) &~ mask) | (e->u << bitoff & mask)); break;
+ }
+ }
+ } else if (ty.t == TYARRAY && ex->t == ESTRLIT) {
+ uint n = ex->s.n * typesize(typechild(ty));
+ if (siz < n) n = siz;
+ /* XXX endian for wide strs */
+ memcpy(p, ex->s.p, n);
+ } else {
+ internstr sym;
+ vlong addend = expr2reloc(&sym, ex);
+ if (!ip->dyn) {
+ assert(ip->sec != Srodata || rodatarelocok());
+ objreloc(sym, targ_64bit ? REL_ABS64 : REL_ABS32,
+ ip->sec, ip->off + off, addend);
+ } else {
+ struct dreloc *rel = alloc(ip->arena, sizeof *rel, 0);
+ rel->link = ip->drel;
+ rel->sym = sym;
+ rel->off = off;
+ rel->addend = addend;
+ ip->drel = rel;
+ }
+ }
+ } else {
+ assert(cm != NULL);
+ struct init *init = ip->init;
+ struct initval val = {
+ .off = off,
+ .bitsiz = bitsiz,
+ .bitoff = bitoff,
+ .ex = *ex
+ }, *new = alloccopy(&cm->exarena, &val, sizeof val, 0);
+ *init->tail = new;
+ init->tail = &new->next;
+ if (!bitsiz) for (uint i = off, end = i + typesize(ex->ty); i < end; ++i) {
+ if (BSSIZE(end) > countof(init->zero)) break;
+ bsclr(init->zero, i);
+ }
+ }
+}
+
+static bool
+iniwriterec(struct comp *cm, struct initparser *ip, uint off, struct expr *ex)
+{
+ assert(ex->t == EINIT);
+ for (struct initval *v = ex->init->vals; v; v = v->next) {
+ if (v->ex.t == EINIT) iniwriterec(cm, ip, off + v->off, &v->ex);
+ else if (ip->ev && !eval(&v->ex, ip->ev) && ip->ev != EVFOLD) return 0;
+ else iniwrite(cm, ip, off + v->off, v->bitsiz, v->bitoff, v->ex.ty, &v->ex);
+ }
+ return 1;
+}
+
+static struct initcur *
+iniadvance(struct initparser *ip, struct initcur *c, const struct span *span)
+{
+ if (c - ip->buf >= countof(ip->buf) - 1)
+ fatal(span, "too many nested initializers");
+ return c + 1;
+}
+
+/* set the initializer cursor object */
+static void
+inifocus(struct initparser *ip, struct comp *cm, const struct span *span, uint idx)
+{
+ while (idx >= nmemb(ip->sub->ty) && ip->sub != ip->cur) {
+ --ip->sub;
+ idx = ip->sub->idx;
+ }
+ uint off, bitsiz, bitoff;
+ union type targ = membertype(&off, &bitsiz, &bitoff, ip->sub->ty, idx);
+ struct initcur *next = iniadvance(ip, ip->cur, span);
+ assert(!bitsiz);
+
+ if (isagg(ip->sub->ty) && targ.t == TYARRAY && !typearrlen(targ))
+ error(span, "cannot initialize flexible array member");
+ excesscheck(ip, span);
+
+ next->ty = targ;
+ next->idx = 0;
+ next->off = ip->sub->off + off;
+ next->prev = ip->cur - ip->buf;
+ ++ip->cur->idx;
+ ip->sub = ip->cur = next;
+}
+
+/* initialize a character array with a string literal */
+static void
+inistrlit(struct comp *cm, struct expr *ex, union type *ty)
+{
+ if (isincomplete(*ty)) {
+ *ty = mkarrtype(typechild(*ty), ty->flag & TFCHLDQUAL, ex->s.n + 1);
+ } else if (typearrlen(*ty) < ex->s.n) {
+ warn(&ex->span, "string literal in initializer is truncated from %u to %u bytes",
+ (ex->s.n+1)*typesize(typechild(*ty)), typesize(*ty));
+ }
+ ex->ty = *ty;
+}
+
+/* read scalar initializer into initializer list and avance */
+static void
+ininext(struct initparser *ip, struct comp *cm)
+{
+ uint off, bitsiz, bitoff;
+ union type targ;
+ struct expr ex = expr(cm);
+
+Retry:
+ targ = membertype(&off, &bitsiz, &bitoff, ip->sub->ty, ip->sub->idx);
+
+ if (isagg(ip->sub->ty) && targ.t == TYARRAY && !typearrlen(targ)) {
+ error(&ex.span, "cannot initialize flexible array member");
+ ++ip->sub->idx;
+ return;
+ }
+ if (ex.t == ESTRLIT && chrarrayof(targ, typechild(ex.ty))) {
+ assert(!isincomplete(targ));
+ inistrlit(cm, &ex, &targ);
+ iniwrite(cm, ip, ip->sub->off + off, 0,0, targ, &ex);
+ ++ip->sub->idx;
+ return;
+ } else if (ex.t == ESTRLIT && ip->sub->idx == 0 && chrarrayof(ip->sub->ty, typechild(ex.ty))) {
+ /* handle e.g. (char []){"foo"} */
+ assert(off == 0);
+ targ = ip->sub->ty;
+ inistrlit(cm, &ex, &targ);
+ iniwrite(cm, ip, ip->sub->off, 0,0, targ, &ex);
+ if (ip->sub == ip->buf && ip->arrlen < ex.s.n+1)
+ ip->arrlen = ex.s.n+1;
+ --ip->sub;
+ return;
+ } else if (ip->sub->idx >= nmemb(ip->sub->ty) && ip->sub != ip->cur) {
+ --ip->sub;
+ goto Retry;
+ } else if (objectp(targ) && targ.bits != ex.ty.bits) {
+ struct initcur *next = iniadvance(ip, ip->sub, &ex.span);
+ if (ip->sub - ip->buf == countof(ip->buf) - 1)
+ fatal(&ex.span, "too many nested initializers");
+ ++ip->sub->idx;
+ *next = (struct initcur) { targ, .off = ip->sub->off + off };
+ ip->sub = next;
+ goto Retry;
+ }
+ excesscheck(ip, &ex.span);
+
+ if (targ.t) {
+ if (!initcheck(targ, &ex))
+ error(&ex.span, "cannot initialize '%ty' with expression of type '%ty'", targ, ex.ty);
+ else {
+ if (targ.bits == ex.ty.bits && ex.t == EINIT) {
+ if (!iniwriterec(cm, ip, ip->sub->off + off, &ex))
+ goto CannotEval;
+ } else if (ip->ev && !eval(&ex, ip->ev) && ip->ev != EVFOLD) {
+ CannotEval:
+ error(&ex.span, "cannot evaluate expression statically");
+ } else {
+ struct expr *pex = &ex;
+ if (ip->ev != EVSTATICINI) {
+ if (ex.ty.bits != targ.bits)
+ ex = mkexpr(ECAST, ex.span, targ, .sub = exprdup(cm, &ex));
+ pex = exprdup(cm, &ex);
+ }
+ iniwrite(cm, ip, ip->sub->off + off, bitsiz, bitoff, targ, pex);
+ }
+ }
+ }
+ if (ip->sub == ip->buf && ip->arrlen < ip->sub->idx+1)
+ ip->arrlen = ip->sub->idx+1;
+
+ if (++ip->sub->idx == 0) {
+ error(&ex.span, "element makes object too large");
+ --ip->sub->idx;
+ }
+}
+
+static int
+aggdesignator(struct initparser *ip, union type ty, internstr name, const struct span *span)
+{
+ const struct typedata *td = &typedata[ty.dat];
+ for (int i = 0; i < td->nmemb; ++i) {
+ struct namedfield *fld = &td->fld[i];
+ if (fld->name == name) {
+ return i;
+ } else if (!fld->name) {
+ int save, sub;
+ struct initcur *next = iniadvance(ip, ip->sub, span);
+ save = ip->sub->idx;
+ ip->sub->idx = i+1;
+ *next = (struct initcur) { fld->f.t, .off = ip->sub->off + fld->f.off };
+ ip->sub = next;
+ sub = aggdesignator(ip, fld->f.t, name, span);
+ if (sub == -1) {
+ --ip->sub;
+ ip->sub->idx = save;
+ } else return sub;
+ }
+ }
+ return -1;
+}
+
+static bool
+designators(struct initparser *ip, struct comp *cm)
+{
+ struct token tk;
+ struct span span;
+ bool some = 0;
+
+ for (;;) {
+ uint off, bitsiz, bitoff;
+ uvlong idx = ~0ull;
+ if (match(cm, &tk, '[')) {
+ struct expr ex = commaexpr(cm);
+ span = tk.span;
+ joinspan(&span.ex, ex.span.ex);
+ peek(cm, &tk);
+ if (some) {
+ union type ty = membertype(&off, &bitsiz, &bitoff, ip->sub->ty, ip->sub->idx++);
+ struct initcur *next = iniadvance(ip, ip->sub, &tk.span);
+ assert(!bitsiz);
+ *next = (struct initcur) { ty, .off = ip->sub->off + off };
+ ip->sub = next;
+ dumpini(ip);
+ }
+ if (expect(cm, ']', NULL)) joinspan(&span.ex, tk.span.ex);
+ if (ip->sub->ty.t != TYARRAY)
+ error(&ex.span, "array designator used with non-array type '%ty'", ip->sub->ty);
+ if (!eval(&ex, EVINTCONST))
+ error(&ex.span, "array designator index is not an integer constant");
+ else if (issigned(ex.ty) && ex.i < 0)
+ error(&ex.span, "negative array designator index");
+ else if (ex.i > ~0u - 1)
+ error(&ex.span, "index too large");
+ else {
+ idx = ex.u;
+ ip->sub->idx = idx;
+ if (ip->sub == ip->buf && ip->arrlen < idx+1)
+ ip->arrlen = idx+1;
+ dumpini(ip);
+ }
+ some = 1;
+ } else if (match(cm, &tk, '.')) {
+ span = tk.span;
+ peek(cm, &tk);
+ if (some) {
+ union type ty = membertype(&off, &bitsiz, &bitoff, ip->sub->ty, ip->sub->idx++);
+ struct initcur *next = iniadvance(ip, ip->sub, &tk.span);
+ *next = (struct initcur) { ty, .off = ip->sub->off + off };
+ ip->sub = next;
+ dumpini(ip);
+ }
+ if (expect(cm, TKIDENT, NULL)) joinspan(&span.ex, tk.span.ex);
+ if (!isagg(ip->sub->ty))
+ error(&span, "member designator used with non-aggregate type '%ty'", ip->sub->ty);
+ else if (tk.t == TKIDENT) {
+ int idx;
+ for (;;) {
+ idx = aggdesignator(ip, ip->sub->ty, tk.name, &span);
+ if (idx >= 0 || ip->sub == ip->cur) break;
+ --ip->sub;
+ }
+ ip->sub->idx = idx;
+ if (idx < 0)
+ error(&span, "%ty has no such field: '%s'", ip->cur->ty, tk.name);
+ dumpini(ip);
+ }
+ some = 1;
+ } else {
+ if (some) {
+ expect(cm, '=', NULL);
+ }
+ return some;
+ }
+ }
+}
+
+static struct expr
+initializer(struct comp *cm, union type *ty, enum evalmode ev, bool globl,
+ enum qualifier qual, internstr sym)
+{
+ struct token tk;
+ struct span span;
+ struct init res = {0};
+ struct initparser ip[1] = {0};
+
+ ip->arena = &cm->exarena;
+ ip->ev = ev;
+ if (ev == EVSTATICINI) {
+ if (ty->t == TYARRAY && isincomplete(*ty)) {
+ ip->dyn = 1;
+ } else if (qual & QCONST && !rodatarelocok()) {
+ ip->dyn = 1;
+ vresize(&ip->ddat, typesize(*ty));
+ memset(ip->ddat.p, 0, typesize(*ty));
+ } else {
+ ip->sec = qual & QCONST ? Srodata : Sdata;
+ if (!nerror)
+ ip->off = objnewdat(sym, ip->sec, globl, typesize(*ty), typealign(*ty));
+ }
+ } else {
+ ip->init = &res;
+ res.tail = &res.vals;
+ }
+
+ if (!match(cm, &tk, '{')) {
+ struct expr ex = expr(cm);
+ if (ex.t == ESTRLIT && chrarrayof(*ty, typechild(ex.ty))) {
+ inistrlit(cm, &ex, ty);
+ iniwrite(cm, ip, 0, 0, 0, *ty, &ex);
+ } else if (!initcheck(*ty, &ex)) {
+ error(&ex.span, "cannot initialize '%ty' with expression of type '%ty'", *ty, ex.ty);
+ } else {
+ if (ev && !eval(&ex, ev) && ev != EVFOLD)
+ error(&ex.span, "cannot evaluate expression statically");
+ else
+ iniwrite(cm, ip, 0, 0, 0, *ty, &ex);
+ }
+ if (ip->dyn)
+ goto Dynfix;
+ return ex;
+ }
+
+ assert(countof(res.zero) == BSSIZE(64));
+ if (ev != EVSTATICINI) {
+ memset(res.zero, 0xFF, sizeof res.zero);
+ }
+
+ span = tk.span;
+ ip->sub = ip->cur = ip->buf;
+ ip->cur->ty = *ty;
+ for (;;) {
+ peek(cm, &tk);
+ joinspan(&span.ex, tk.span.ex);
+ if (tk.t == '[' || tk.t == '.') {
+ designators(ip, cm);
+ }
+ if (match(cm, &tk, '}')) {
+ if (ip->cur == ip->buf) break;
+ ip->sub = ip->cur = ip->buf + ip->cur->prev;
+ dumpini(ip);
+ } else if (match(cm, &tk, '{')) {
+ struct span span = tk.span;
+ inifocus(ip, cm, &tk.span, ip->sub->idx);
+ if (peek(cm, &tk) == '}') {
+ if (!joinspan(&span.ex, tk.span.ex)) span = tk.span;
+ if (!objectp(ip->sub->ty)) {
+ error(&span, "scalar initializer cannot be empty");
+ } else if (ccopt.cstd < STDC23 && ccopt.pedant) {
+ warn(&span, "empty initializer in %M is an extension");
+ }
+ } else if (ip->sub->ty.t && !objectp(ip->sub->ty)) {
+ warn(&span, "brace initializer for scalar object '%ty'", ip->sub->ty);
+ }
+ continue;
+ } else {
+ dumpini(ip);
+ ininext(ip, cm);
+ }
+ match(cm, NULL, ',');
+ if (peek(cm, &tk) != '}' && ip->sub->ty.t == TYUNION) {
+ if (ip->sub == ip->cur) {
+ warn(&tk.span, "excess elements in union initializer");
+ } else while (ip->sub != ip->cur && ip->sub->ty.t == TYUNION) {
+ --ip->sub;
+ }
+ }
+ }
+ if (ip->dyn) {
+ enum section sec;
+ uint off, siz, align;
+ uchar *p;
+
+ if (isincomplete(*ty)) {
+ uint len = ip->arrlen > ip->cur->idx ? ip->arrlen : ip->cur->idx;
+ if (len == 0)
+ error(&span, "array cannot have zero length");
+ *ty = mkarrtype(typechild(*ty), ty->flag & TFCHLDQUAL, len);
+ }
+ Dynfix:
+ if (qual & QCONST && (ip->drel == NULL || rodatarelocok()))
+ sec = Srodata;
+ else
+ sec = Sdata;
+ if (!nerror) {
+ off = objnewdat(sym, sec, globl, siz = typesize(*ty), align = typealign(*ty));
+ p = sec == Srodata ? objout.rodata.p : objout.data.p;
+ memcpy(p + off, ip->ddat.p, ip->ddat.n);
+ memset(p + off + ip->ddat.n, 0, typesize(*ty) - ip->ddat.n);
+ for (struct dreloc *rel = ip->drel; rel; rel = rel->link) {
+ objreloc(rel->sym, targ_64bit ? REL_ABS64 : REL_ABS32, sec, off + rel->off, rel->addend);
+ }
+ }
+ vfree(&ip->ddat);
+ }
+ dumpini(ip);
+
+ if (ev == EVSTATICINI) {
+ return (struct expr){.span = span};
+ } else {
+ uint siz;
+ if (isincomplete(*ty)) {
+ uint len = ip->arrlen > ip->cur->idx ? ip->arrlen : ip->cur->idx;
+ if (!len)
+ error(&span, "initializer creates a zero-sized array");
+ *ty = mkarrtype(typechild(*ty), ty->flag & TFCHLDQUAL, len);
+ }
+
+ assert(countof(res.zero) == 1);
+ siz = typesize(*ty);
+ if (siz && siz <= 64)
+ res.zero->u &= ~0ull >> (64 - siz);
+
+ return mkexpr(EINIT, span, *ty, .init = alloccopy(&cm->exarena, &res, sizeof res, 0));
+ }
+}
+
+/* debugging */
+void
+dumpexpr(const struct expr *ex, bool prity)
+{
+ static const char *name[] = {
+ [EXXX] = "xxx", [ENUMLIT] = "numlit", [ESTRLIT] = "strlit",
+ [ESSYMREF] = "ssymref", [ESYM] = "sym", [EVAARG] = "vaarg",
+ [EINIT] = "init", [EGETF] = "getf", [ECALL] = "call",
+ [ECOND] = "cond", [EPLUS] = "plus", [ENEG] = "neg",
+ [ECOMPL] = "compl", [ELOGNOT] = "lognot", [EDEREF] = "deref",
+ [EADDROF] = "addrof", [ECAST] = "cast", [EPREINC] = "preinc",
+ [EPOSTINC] = "postinc", [EPREDEC] = "predec", [EPOSTDEC] = "postdec",
+ [EADD] = "add", [ESUB] = "sub", [EMUL] = "mul",
+ [EDIV] = "div", [EREM] = "rem", [EBAND] = "band",
+ [EBIOR] = "bior", [EXOR] = "xor", [ESHL] = "shl",
+ [ESHR] = "shr", [ELOGAND] = "logand", [ELOGIOR] = "logior",
+ [EEQU] = "equ", [ENEQ] = "neq", [ELTH] = "lth",
+ [EGTH] = "gth", [ELTE] = "lte", [EGTE] = "gte",
+ [ESET] = "set", [ESETADD] = "setadd", [ESETSUB] = "setsub",
+ [ESETMUL] = "setmul", [ESETDIV] = "setdiv", [ESETREM] = "setrem",
+ [ESETAND] = "setand", [ESETIOR] = "setior", [ESETXOR] = "setxor",
+ [ESETSHL] = "setshl", [ESETSHR] = "setshr", [ESEQ] = "seq",
+ };
+ ioputc(&bstderr, '(');
+ efmt("%s ", name[ex->t]);
+ if (ex->ty.t && (prity || ex->t == EVAARG || ex->t == ECAST))
+ efmt("<%ty> ", ex->ty);
+ int nsub = 0;
+ switch (ex->t) {
+ case ENUMLIT: if (!isflt(ex->ty)) efmt(isunsigned(ex->ty) ? "%lu" : "%ld", ex->u);
+ else efmt("%f", ex->f);
+ break;
+ case ESTRLIT: efmt("%'S", ex->s.p, ex->s.n); break; /* XXX widestr */
+ case ESYM: efmt("%y", declsbuf.p[ex->decl].name); break;
+ case ESSYMREF: efmt("%y%+d", ex->ssym.sym, ex->ssym.off);
+ if (ex->ssym.func) efmt(" @func");
+ if (ex->ssym.local) efmt(" @local");
+ break;
+ case EVAARG: dumpexpr(ex->sub, prity); break;
+ case EGETF: dumpexpr(ex->sub, prity); efmt(" #+%u", ex->fld.off);
+ if (ex->fld.bitsiz) efmt("[%d:%d]", ex->fld.bitoff, ex->fld.bitsiz);
+ break;
+ case ECALL: nsub = ex->narg+1; goto Sub;
+ case ECOND: nsub = ex->narg+1; goto Sub;
+ default:
+ if (in_range(ex->t, EPLUS, EPOSTDEC)) nsub = 1;
+ else nsub = 2;
+ Sub:
+ for (int i = 0; i < nsub; ++i) {
+ if (i) ioputc(&bstderr, ' ');
+ dumpexpr(&ex->sub[i], prity);
+ }
+ break;
+ case EINIT: assert(!"nyi");
+ }
+ ioputc(&bstderr, ')');
+}
+
+/*****************/
+/* Decls Parsing */
+/*****************/
+
+static union type
+buildagg(struct comp *cm, enum typetag tt, internstr name, int id)
+{
+ struct token tk;
+ union type t;
+ struct span flexspan;
+ struct namedfield fbuf[32];
+ vec_of(struct namedfield) fld = VINIT(fbuf, countof(fbuf));
+ struct typedata td = {tt};
+ bool isunion = tt == TYUNION;
+ const char *tag = isunion ? "union" : "struct";
+ uint bitsiz = 0, bitfbyteoff = 0,
+ bitoff = 0, bitftypesiz = 0;
+
+ while (!match(cm, &tk, '}')) {
+ struct declstate st = { DFIELD };
+ do {
+ struct decl decl = pdecl(&st, cm);
+ uint tysize;
+ if (st.empty) {
+ if (ccopt.pedant)
+ warn(&decl.span, "extra semicolon in aggregate");
+ continue;
+ }
+ tysize = typesize(decl.ty);
+ if (fld.n && td.flexi) {
+ td.flexi = 0;
+ error(&flexspan, "flexible array member is not at end of struct");
+ }
+ if (!isunion && decl.ty.t == TYARRAY && !typearrlen(decl.ty)) {
+ td.flexi = 1;
+ flexspan = decl.span;
+ } else if (isincomplete(decl.ty)) {
+ error(&decl.span, "field has incomplete type '%ty'", decl.ty);
+ } else if (decl.ty.t == TYFUNC) {
+ error(&decl.span, "field has function type '%ty'", decl.ty);
+ }
+ bitsiz = 0;
+ if (st.bitf) {
+ struct expr ex = constantexpr(cm);
+ const char *name = decl.name ? &decl.name->c : "<anonymous>";
+ if (!isint(decl.ty)) {
+ error(&decl.span, "bit-field '%s' has non-integer type '%ty'", name, decl.ty);
+ } else if (!isint(ex.ty)) {
+ error(&ex.span, "integer constant expression has non-integer type '%ty'", decl.ty);
+ } else if (!eval(&ex, EVINTCONST)) {
+ 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*tysize) {
+ error(&ex.span, "width of bit-field '%s' (%ld) exceeds width of type (%d)",
+ name, ex.i, 8*tysize);
+ } else if (ex.i == 0 && decl.name) {
+ error(&ex.span, "named bit-field '%s' has zero width", name);
+ } else {
+ bitsiz = ex.i;
+ if (bitsiz == 0) {
+ if (bitftypesiz) {
+ bitfbyteoff += bitftypesiz;
+ bitfbyteoff = alignup(bitfbyteoff, typealign(decl.ty));
+ }
+ bitoff = 0;
+ } else if (bitftypesiz && bitftypesiz < tysize) {
+ /* end of previous bitfield */
+ bitoff = 0;
+ bitfbyteoff += bitftypesiz;
+ } else if (!bitftypesiz) {
+ bitoff = 0;
+ bitfbyteoff = alignup(td.siz, typealign(decl.ty));
+ } else if (bitoff + bitsiz > 8*bitftypesiz) {
+ /* no straddling boundaries */
+ bitoff = 0;
+ bitfbyteoff += bitftypesiz;
+ }
+ if (tysize > bitftypesiz) bitftypesiz = tysize;
+ }
+ pdecl(&st, cm);
+ } else {
+ bitftypesiz = bitoff = bitsiz = 0;
+ }
+ if (decl.ty.t) {
+ uint align = typealign(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) {
+ /* adjust bitfields narrower than container type */
+ f.f.off += siz;
+ f.f.bitoff -= 8*siz;
+ }
+ if (!decl.name && !bitftypesiz) {
+ if (!isagg(decl.ty) || ttypenames[typedata[decl.ty.dat].id]) {
+ warn(&decl.span, "declaration does not declare anything");
+ continue;
+ } else if (ccopt.cstd < STDC11 && ccopt.pedant) {
+ warn(&decl.span, "anonymous %s in %M is an extension",
+ decl.ty.t == TYUNION ? "union" : "struct");
+ }
+ }
+ if (decl.name || !bitftypesiz)
+ vpush(&fld, f);
+ td.anyconst |= decl.qual & QCONST;
+ if (isagg(decl.ty)) {
+ td.anyconst |= typedata[decl.ty.dat].anyconst;
+ if (typedata[decl.ty.dat].flexi && !isunion)
+ error(&decl.span, "nested aggregate has flexible array member");
+ }
+ if (isunion)
+ td.siz = td.siz < siz ? siz : td.siz;
+ else
+ td.siz = off + siz;
+ td.align = td.align < align ? align : td.align;
+ bitoff += bitsiz;
+ }
+ } while (st.more);
+ }
+ if (td.flexi && fld.n == 1)
+ error(&flexspan, "flexible array member in otherwise empty aggregate");
+ if (td.flexi && ccopt.cstd < STDC99 && ccopt.pedant)
+ warn(&flexspan, "flexible array member in %M is an extension");
+ if (fld.n == 0) {
+ struct namedfield dummy = { intern(""), { mktype(TYCHAR), 0 }};
+ error(&tk.span, "%s cannot have zero members", tag);
+ vpush(&fld, dummy);
+ td.siz = td.align = 1;
+ }
+ td.siz = alignup(td.siz, td.align);
+ td.fld = fld.p;
+ td.nmemb = fld.n;
+ if (id != -1)
+ t = completetype(name, id, &td);
+ else
+ t = mktagtype(name, &td);
+ vfree(&fld);
+ return t;
+}
+
+static inline void
+inttyminmax(vlong *min, uvlong *max, enum typetag tt)
+{
+ uint bits = 8*targ_primsizes[tt];
+ *min = isunsignedt(tt) ? 0 : -(1ull << (bits - 1));
+ *max = isunsignedt(tt) ? ~0ull >> (64 - bits) : bits == 64 ? ~0ull>>1 : (1ll << (bits - 1)) - 1;
+}
+
+/* the backing type of enum (without a C23 fixed backing type) is int or the
+ * smallest-rank type that all the enumerators fit in, or if it doesn't exist,
+ * then the biggest signed type. the type of enumeration constants is the type of
+ * its defining expression when present or the type of the previous enumerator
+ * or in case of overflow the smallest type that fits (previous value + 1)
+ * this isn't strictly conforming since pre C23 enums are pretty loosely defined,
+ * and this is similar to existing compiler's de-facto behaviour (though gcc
+ * prefers to use unsigned types when possible). should add support for -fshort-enums
+ */
+static union type
+buildenum(struct comp *cm, internstr name, const struct span *span, int id)
+{
+ struct token tk;
+ vlong tymin, minv = 0;
+ uvlong tymax, maxv = 0;
+ struct typedata td = {TYENUM, .backing = TYINT};
+ union type ty = mktype(td.backing);
+ struct span maxvspan;
+ vlong iota = 0;
+ bool somelonglong = 0;
+
+ inttyminmax(&tymin, &tymax, td.backing);
+ while (!match(cm, &tk, '}')) {
+ struct decl decl = {0};
+ peek(cm, &tk);
+ expect(cm, TKIDENT, NULL);
+ if (match(cm, NULL, '=') || (peek(cm, NULL) == TKNUMLIT && !expect(cm, '=', NULL))) {
+ struct expr ex = expr(cm);
+ if (eval(&ex, EVINTCONST)) {
+ iota = ex.i;
+ if (ex.ty.t != ty.t)
+ inttyminmax(&tymin, &tymax, ex.ty.t);
+ ty = ex.ty;
+ } else {
+ error(&ex.span, "enum value is not an integer constant");
+ }
+ } else if (tk.t != TKIDENT) {
+ lex(cm, NULL);
+ continue;
+ }
+ while (issigned(ty) ? (iota > (vlong)tymax || iota < tymin) : iota > tymax)
+ inttyminmax(&tymin, &tymax, ++ty.t);
+ somelonglong |= ty.t >= TYVLONG;
+ if ((isunsigned(ty) || iota > 0) && iota > maxv)
+ maxv = iota, maxvspan = tk.span;
+ else if (issigned(ty) && iota < minv)
+ minv = iota;
+
+ decl.name = tk.name;
+ decl.ty = ty;
+ decl.isenum = 1;
+ decl.value = iota++;
+ putdecl(cm, &decl);
+ if (!match(cm, &tk, ',')) {
+ if (expect(cm, '}', "or `,'"))
+ break;
+ else lex(cm, NULL);
+ }
+ }
+
+ td.backing = 0;
+ if (minv >= 0 && maxv <= ~0u) {
+ td.backing = TYUINT;
+ } else for (int t = TYINT; t <= TYUVLONG; ++t) {
+ inttyminmax(&tymin, &tymax, t);
+ if (minv >= tymin && maxv <= tymax) {
+ td.backing = t;
+ break;
+ }
+ }
+ if (!td.backing) {
+ td.backing = !somelonglong && ccopt.cstd == STDC89 && ccopt.pedant ? TYLONG : TYVLONG;
+ warn(&maxvspan, "enumerators exceed range of enum's backing type '%ty'", mktype(td.backing));
+ }
+ if (td.backing >= TYVLONG && !somelonglong && ccopt.cstd == STDC89 && ccopt.pedant)
+ warn(span, "enum backing type is '%ty' in %M", mktype(td.backing));
+
+ if (id != -1)
+ ty = completetype(name, id, &td);
+ else
+ ty = mktagtype(name, &td);
+ ty.backing = td.backing;
+ return ty;
+}
+
+static union type
+tagtype(struct comp *cm, enum toktag kind)
+{
+ struct token tk;
+ union type t;
+ struct span span;
+ enum typetag tt = kind == TKWenum ? TYENUM : kind == TKWstruct ? TYSTRUCT : TYUNION;
+ internstr tag = NULL;
+
+ peek(cm, &tk);
+ if (match(cm, &tk, TKIDENT))
+ tag = tk.name;
+ span = tk.span;
+ if (!match(cm, NULL, '{')) {
+ if (!tag) {
+ error(&tk.span, "expected %tt name or '{'", kind);
+ return mktype(0);
+ }
+ t = gettagged(cm, &span, tt, tag, /* def? */ peek(cm, NULL) == ';');
+ } else {
+ if (tag) {
+ t = deftagged(cm, &span, tt, tag, mktype(0));
+ if (t.t != tt || !isincomplete(t)) {
+ if (t.t != tt)
+ error(&tk.span,
+ "defining tagged type %'tk as %tt clashes with previous definition",
+ &tk, kind);
+ else
+ error(&tk.span, "redefinition of '%tt %s'", kind, tag);
+ note(&span, "previous definition:");
+ }
+ }
+ if (tt == TYENUM)
+ t = buildenum(cm, tag, &span, tag ? typedata[t.dat].id : -1);
+ else
+ t = buildagg(cm, tt, tag, tag ? typedata[t.dat].id : -1);
+ }
+
+ if (t.t != tt) {
+ error(&tk.span, "declaring tagged type %'tk as %tt clashes with previous definition",
+ &tk, kind);
+ note(&span, "previous definition:");
+ }
+ return t;
+}
+
+static bool
+attrspec(struct comp *cm, int *attr)
+{ /* __attribute__ (( attribute-list )) */
+ if (!match(cm, NULL, TKW__attribute__)) return 0;
+ if (!expect(cm, '(', "after __attribute__") || !expect(cm, '(', "after __attribute__")) {
+ Bad:
+ fatal(NULL, NULL);
+ }
+ while (!match(cm, NULL, ')')) {
+ struct token tk;
+ lex(cm, &tk);
+ if (tk.t != TKIDENT && !in_range(tk.t, TKWBEGIN_, TKWEND_)) {
+ fatal(&tk.span, "expected attribute name");
+ }
+ internstr name = tk.name;
+ int ltrim = name[0].c == '_' && name[1].c == '_',
+ rtrim = tk.len > 2 && name[tk.len-1].c == '_' && name[tk.len-2].c == '_';
+ if (ltrim || rtrim) { /* trim surrounding '__' */
+ name = intern_(&name->c + ltrim*2, tk.len - ltrim*2 - rtrim*2);
+ }
+ if (match(cm, NULL, '(')) {
+ while (!match(cm, NULL, ')')) {
+ (void)exprparse(cm, bintab['='].prec, NULL, EATTRARG);
+ if (!match(cm, NULL, ',')) {
+ if (expect(cm, ')', NULL)) break;
+ else goto Bad;
+ }
+ }
+ }
+ (void)name;
+ if (!match(cm, NULL, ',')) {
+ if (expect(cm, ')', NULL)) break;
+ else goto Bad;
+ }
+ }
+ if (!expect(cm, ')', NULL))
+ goto Bad;
+ return 1;
+}
+
+static union type
+ptypeof(struct comp *cm)
+{
+ union type ty;
+ expect(cm, '(', NULL);
+ if (isdecltok(cm)) { /* typeof (type) */
+ struct declstate st = { DCASTEXPR };
+ ty = pdecl(&st, cm).ty;
+ } else { /* typeof (expr) */
+ ty = commaexpr(cm).ty;
+ }
+ expect(cm, ')', NULL);
+ return ty;
+}
+
+static void
+declspec(struct declstate *st, struct comp *cm, struct span *pspan)
+{
+ struct token tk;
+ struct decl *decl;
+ enum arith {
+ KSIGNED = 1<<0,
+ KUNSIGNED = 1<<1,
+ KBOOL = 1<<2,
+ KCHAR = 1<<3,
+ KSHORT = 1<<4,
+ KLONG = 1<<5,
+ KLONGLONG = 1<<6,
+ KINT = 1<<7,
+ KFLOAT = 1<<8,
+ KDOUBLE = 1<<9,
+ KCOMPLEX = 1<<10,
+ } arith = 0;
+ struct span span = {0};
+ union type ty = st->base;
+ bool properdecl = st->kind == DFUNCVAR || st->kind == DTOPLEVEL;
+
+ for (bool first = 1;; first = 0) {
+ enum storageclass scls = 0;
+ peek(cm, &tk);
+ if (first) span = tk.span;
+ switch (tk.t) {
+ /* storage-class-specifier */
+ case TKWtypedef: scls = SCTYPEDEF; break;
+ case TKWextern: scls = SCEXTERN; break;
+ case TKWstatic: scls = SCSTATIC; break;
+ case TKWauto: scls = SCAUTO; break;
+ case TKWregister: scls = SCREGISTER; break;
+ case TKWthread_local:
+ case TKW_Thread_local: scls = SCTHREADLOCAL; break;
+
+ /* function-specifier */
+ case TKWinline:
+ if (!properdecl) BadFnSpec: {
+ error(&tk.span, "function specifier %'tk is not allowed here", &tk);
+ break;
+ }
+ st->fninline = 1;
+ break;
+ case TKW_Noreturn:
+ if (!properdecl) goto BadFnSpec;
+ st->fnnoreturn = 1;
+ break;
+
+ /* alignment-specifier */
+ case TKW_Alignas: assert(!"nyi alignas"); break;
+
+ /* type-qualifier */
+ case TKWconst: st->qual |= QCONST; break;
+ case TKWvolatile: st->qual |= QVOLATILE; break;
+ case TKWrestrict: /* unimplemented */ break;
+ case TKW_Atomic: /* unimplemented */ break;
+
+ /* type-specifier */
+ case TKWvoid:
+ if (st->base.t) {
+ DupBase:
+ error(&tk.span, "more than one data type in declaration specifier");
+ } else {
+ st->base = mktype(TYVOID);
+ }
+ break;
+ case TKWsigned:
+ arith |= KSIGNED;
+ break;
+ case TKWunsigned:
+ arith |= KUNSIGNED;
+ break;
+ case TKW_Bool: case TKWbool:
+ if (arith & KBOOL) goto DupArith;
+ arith |= KBOOL;
+ break;
+ case TKWchar:
+ if (arith & KCHAR) {
+ DupArith:
+ error(&tk.span, "duplicate %tk specifier", &tk);
+ }
+ arith |= KCHAR;
+ break;
+ case TKWshort:
+ arith |= KSHORT;
+ break;
+ case TKWlong:
+ if ((arith & (KLONG | KLONGLONG)) == KLONG)
+ arith = (arith &~ KLONG) | KLONGLONG;
+ else if ((arith & (KLONG | KLONGLONG)) == 0)
+ arith |= KLONG;
+ else
+ error(&tk.span, "too long");
+ break;
+ case TKWint:
+ if (arith & KINT) goto DupArith;
+ arith |= KINT;
+ break;
+ case TKWfloat:
+ if (arith & KFLOAT) goto DupArith;
+ arith |= KFLOAT;
+ break;
+ case TKWdouble:
+ if (arith & KDOUBLE) goto DupArith;
+ arith |= KDOUBLE;
+ break;
+ case TKW_Complex:
+ if (arith & KCOMPLEX) goto DupArith;
+ arith |= KCOMPLEX;
+ break;
+ case TKWenum:
+ case TKWstruct:
+ case TKWunion:
+ lex(cm, &tk);
+ ty = tagtype(cm, tk.t);
+ st->tagdecl = 1;
+ joinspan(&span.ex, tk.span.ex);
+ if (st->base.t) goto DupBase;
+ st->base = ty;
+ continue;
+ case TKW__typeof__: case TKWtypeof:
+ lex(cm, &tk);
+ ty = ptypeof(cm);
+ joinspan(&span.ex, tk.span.ex);
+ if (st->base.t) goto DupBase;
+ st->base = ty;
+ continue;
+ case TKIDENT:
+ if (!st->base.t && !arith && (decl = finddecl(cm, tk.name))
+ && decl->scls == SCTYPEDEF) {
+ lex(cm, &tk);
+ st->base = decl->ty;
+ continue;
+ }
+ /* fallthru */
+ default:
+ goto End;
+ case TKW_BitInt:
+ case TKW_Decimal128: case TKW_Decimal32:
+ case TKW_Decimal64: case TKW_Imaginary:
+ error(&tk.span, "%'tk is unsupported", &tk);
+ arith = arith ? arith : KINT;
+ }
+
+ if ((!properdecl && scls && !(st->kind == DFUNCPARAM && scls == SCREGISTER)) || (scls == SCAUTO && st->kind == DTOPLEVEL))
+ error(&tk.span, "storage class specifier %'tk is not allowed here", &tk);
+ else
+ st->scls |= scls;
+
+ joinspan(&span.ex, tk.span.ex);
+ lex(cm, &tk);
+ }
+End:
+ if (pspan) *pspan = span;
+
+ if (st->scls && properdecl) {
+ if (popcnt(st->scls) > 1)
+ error(&span, "invalid combination of storage class specifiers");
+ }
+ if (st->base.t && arith) {
+ /* combining arith type specifiers and other types */
+ Bad:
+ error(&span, "invalid type specifiers");
+ st->base = mktype(TYINT);
+ } else if (!st->base.t && arith) {
+ enum typetag t;
+ if (arith == KFLOAT)
+ t = TYFLOAT;
+ else if (arith == KDOUBLE)
+ t = TYDOUBLE;
+ else if (arith == (KLONG | KDOUBLE))
+ t = TYLDOUBLE;
+ else if (arith == KBOOL)
+ t = TYBOOL;
+ else if (arith == KCHAR)
+ t = TYCHAR;
+ else if (arith == (KSIGNED | KCHAR))
+ t = TYSCHAR;
+ else if (arith == (KUNSIGNED | KCHAR))
+ t = TYUCHAR;
+ else if ((arith & ~KINT & ~KSIGNED) == KSHORT)
+ t = TYSHORT;
+ else if ((arith & ~KINT) == (KUNSIGNED | KSHORT))
+ t = TYUSHORT;
+ else if ((arith & ~KINT & ~KSIGNED) == 0)
+ t = TYINT;
+ else if ((arith & ~KINT) == KUNSIGNED)
+ t = TYUINT;
+ else if ((arith & ~KINT & ~KSIGNED) == KLONG)
+ t = TYLONG;
+ else if ((arith & ~KINT) == (KUNSIGNED | KLONG))
+ t = TYULONG;
+ else if ((arith & ~KINT & ~KSIGNED) == KLONGLONG)
+ t = TYVLONG;
+ else if ((arith & ~KINT) == (KUNSIGNED | KLONGLONG))
+ t = TYUVLONG;
+ else if (arith == (KCOMPLEX | KFLOAT))
+ t = TYCOMPLEXF;
+ else if (arith == (KCOMPLEX | KDOUBLE))
+ t = TYCOMPLEX;
+ else if (arith == (KCOMPLEX | KLONG | KDOUBLE))
+ t = TYCOMPLEXL;
+ else
+ goto Bad;
+ st->base = mktype(t ? t : TYINT);
+ } else if (!st->base.t) {
+ if (ccopt.cstd < STDC23 && peek(cm, NULL) == TKIDENT) {
+ if (ccopt.cstd > STDC89)
+ warn(&tk.span, "type implicitly declared as int");
+ st->base = mktype(TYINT);
+ } else {
+ error(&tk.span, "type specifier missing");
+ }
+ }
+}
+
+/* circular doubly linked list used to parse declarators */
+enum { EARRAYUNSIZED = 0xFF /* for count.t */ };
+static struct decllist {
+ struct decllist *prev, *next;
+ uchar t; /* TYPTR, TYARRAY or TYFUNC */
+ union {
+ uchar qual; /* TYPTR */
+ struct expr count; /* TYARRAY */
+ struct { /* TYFUNC */
+ union type *param;
+ internstr *pnames;
+ struct span *pspans;
+ uchar *pqual;
+ short npar;
+ bool kandr : 1, variadic : 1;
+ };
+ };
+ struct span span;
+} decltmp[64], *declfreelist;
+static bool usingdeclparamtmp;
+static union type declparamtmp[16];
+static internstr declpnamestmp[16];
+static struct span declpspanstmp[16];
+static uchar declpqualtmp[16];
+
+static void
+declinsert(struct decllist *list, const struct decllist *node)
+{
+ struct decllist *pnode = declfreelist;
+ if (!pnode) fatal(NULL, "too many nested declarators");
+ declfreelist = declfreelist->next;
+ *pnode = *node;
+ pnode->next = list->next;
+ pnode->prev = list;
+ list->next->prev = pnode;
+ list->next = pnode;
+}
+
+static int
+cvqual(struct comp *cm)
+{
+ struct token tk;
+ int q = 0;
+ while (match(cm, &tk, TKWconst) || match(cm, &tk, TKWvolatile) || match(cm, &tk, TKWrestrict))
+ q |= tk.t == TKWconst ? QCONST : tk.t == TKWvolatile ? QVOLATILE : 0;
+ return q;
+}
+
+static void
+decltypes(struct comp *cm, struct decllist *list, internstr *name, struct span *span, struct span *namespan)
+{
+ struct token tk;
+ struct decllist *ptr, node;
+
+ while (match(cm, &tk, '*')) {
+ node.t = TYPTR;
+ node.qual = cvqual(cm);
+ node.span = tk.span;
+ declinsert(list, &node);
+ joinspan(&span->ex, tk.span.ex);
+ }
+ ptr = list->next;
+ switch (peek(cm, &tk)) {
+ case '(':
+ lex(cm, &tk);
+ if (isdecltok(cm)) {
+ goto Func;
+ } else if (match(cm, &tk, ')')) {
+ /* T () is K&R func proto */
+ node.span = tk.span;
+ node.t = TYFUNC;
+ node.param = NULL;
+ node.pqual = NULL;
+ node.pnames = NULL;
+ node.pspans = NULL;
+ node.variadic = 0;
+ node.kandr = 1;
+ node.npar = 0;
+ declinsert(ptr->prev, &node);
+ joinspan(&span->ex, tk.span.ex);
+ break;
+ } else {
+ decltypes(cm, list, name, span, namespan);
+ expect(cm, ')', NULL);
+ joinspan(&span->ex, tk.span.ex);
+ }
+ break;
+ case TKIDENT:
+ if (!name)
+ error(&tk.span, "unexpected identifier in type name");
+ else {
+ *name = tk.name;
+ *namespan = tk.span;
+ }
+ lex(cm, &tk);
+ joinspan(&span->ex, tk.span.ex);
+ break;
+ default:
+ if (name)
+ *name = NULL;
+ }
+ for (;;) {
+ if (match(cm, &tk, '[')) {
+ node.span = tk.span;
+ int q = 0;
+ bool statik = 0;
+ if (in_range(peek(cm, &tk), TKWBEGIN_, TKWEND_)) {
+ q = cvqual(cm);
+ statik = match(cm, NULL, TKWstatic);
+ q |= cvqual(cm);
+ }
+ (void)q, (void)statik; /* stub */
+
+ if (match(cm, &tk, ']')) {
+ node.count.t = EARRAYUNSIZED;
+ } else {
+ node.count = arraycountexpr(cm);
+ peek(cm, &tk);
+ joinspan(&node.span.ex, tk.span.ex);
+ expect(cm, ']', NULL);
+ }
+ node.t = TYARRAY;
+ declinsert(ptr->prev, &node);
+ joinspan(&span->ex, node.span.ex);
+ } else if (match(cm, &tk, '(')) Func: {
+ vec_of(union type) params = {0};
+ vec_of(uchar) qual = {0};
+ vec_of(internstr) names = {0};
+ vec_of(struct span) spans = {0};
+
+ if (!usingdeclparamtmp) {
+ usingdeclparamtmp = 1;
+ vinit(&params, declparamtmp, countof(declparamtmp));
+ vinit(&qual, declpqualtmp, countof(declpqualtmp));
+ vinit(&names, declpnamestmp, countof(declpnamestmp));
+ vinit(&spans, declpspanstmp, countof(declpspanstmp));
+ }
+
+ node.span = tk.span;
+ node.kandr = 0;
+ node.variadic = 0;
+ if (ccopt.cstd < STDC23 && !isdecltok(cm)) {
+ node.kandr = 1;
+ }
+
+ if (!match(cm, &tk, ')')) for (;;) {
+ if (match(cm, &tk, TKDOTS)) {
+ node.variadic = 1;
+ expect(cm, ')', NULL);
+ break;
+ }
+ if (node.kandr) {
+ if (match(cm, &tk, TKIDENT)) {
+ vpush(&params, mktype(TYINT));
+ vpush(&names, tk.name);
+ vpush(&spans, tk.span);
+ } else error(&tk.span, "expected identifier");
+ } else if (!isdecltok(cm) && peek(cm, &tk) != TKIDENT) {
+ error(&tk.span, "expected parameter declarator");
+ } else {
+ struct declstate st = { DFUNCPARAM };
+ struct decl decl;
+ decl = pdecl(&st, cm);
+ decl.ty = typedecay(decl.ty);
+ vpush(&params, decl.ty);
+ vpush(&names, decl.name);
+ vpush(&spans, decl.span);
+ vpush(&qual, decl.qual);
+ if (decl.ty.t == TYVOID) {
+ if (params.n > 1 || decl.qual || decl.name || peek(cm, &tk) != ')') {
+ error(&decl.span, "function parameter #%d has void type",
+ params.n, decl.ty, qual.p[params.n-1]);
+ }
+ }
+ }
+ peek(cm, &tk);
+ joinspan(&node.span.ex, tk.span.ex);
+ if (!match(cm, &tk, ',')) {
+ expect(cm, ')', "or `,'");
+ break;
+ }
+ } else {
+ if (ccopt.cstd < STDC23) node.kandr = 1;
+ }
+ if (node.kandr && ccopt.cstd != STDC89 && params.n > 0) {
+ warn(&node.span, "K&R function prototype is deprecated");
+ } else if (params.n == 1 && params.p[0].t == TYVOID && !qual.p[0] && !names.p[0]) { /* (void) */
+ vfree(&params);
+ vfree(&names);
+ vfree(&spans);
+ vfree(&qual);
+ }
+ node.t = TYFUNC;
+ node.param = params.n ? params.p : NULL;
+ node.pqual = qual.n ? qual.p : NULL;
+ node.pnames = params.n ? names.p : NULL;
+ node.pspans = params.n ? spans.p : NULL;
+ node.npar = params.n;
+ declinsert(ptr->prev, &node);
+ joinspan(&span->ex, node.span.ex);
+ } else break;
+ }
+}
+
+static struct decl
+declarator(struct declstate *st, struct comp *cm, struct span span0) {
+ struct decl decl = { st->base, st->scls, .qual = st->qual, .align = st->align, .span = span0 };
+ struct decllist list = { &list, &list }, *l;
+ static bool inidecltmp = 0;
+ struct span namespan ={0};
+ if (!inidecltmp) {
+ inidecltmp = 1;
+ for (int i = 0; i < countof(decltmp); ++i) {
+ decltmp[i].next = declfreelist;
+ declfreelist = &decltmp[i];
+ }
+ }
+
+ decltypes(cm, &list, st->kind == DCASTEXPR ? NULL : &decl.name, &decl.span, &namespan);
+ if (!decl.name && st->kind != DCASTEXPR && st->kind != DFUNCPARAM) {
+ if (list.prev == &list) lex(cm, NULL);
+ error(&decl.span, "expected `(', `*' or identifier");
+ }
+ for (l = list.prev; l != &list; l = l->prev) {
+ switch (l->t) {
+ case TYPTR:
+ decl.ty = mkptrtype(decl.ty, decl.qual);
+ decl.qual = l->qual;
+ break;
+ case TYARRAY:
+ if (isincomplete(decl.ty))
+ error(&l->span, "array has incomplete element type '%ty'", decl.ty);
+ else if (decl.ty.t == TYFUNC)
+ error(&l->span, "array has element has function type '%ty'", decl.ty);
+ if (l->count.t == EARRAYUNSIZED) /* unsized '[]' */
+ decl.ty = mkarrtype(decl.ty, decl.qual, 0);
+ else {
+ uint n = 0;
+ struct expr *ex = &l->count;
+ if (!ex->t) { /* ['*'] */
+ if (l->prev != &list) error(&l->span, "[*] array declarator is not allowed here");
+ } else if (!eval(ex, EVINTCONST)) {
+ error(&ex->span, "array length is not an integer constant");
+ } else if (issigned(ex->ty) && ex->i < 0) {
+ error(&ex->span, "array length is negative");
+ } else if (ex->u > (1ull << (8*sizeof n)) - 1) {
+ error(&ex->span, "array too long (%ul)", ex->u);
+ } else if (ex->u == 0) {
+ /* when struct field, silently accept zero-length as synonym of '[]' for flexible array member */
+ if (l->prev != &list || st->kind != DFIELD) {
+ warn(&ex->span, "array cannot have zero length");
+ }
+ } else {
+ n = ex->u;
+ }
+ decl.ty = mkarrtype(decl.ty, decl.qual, n);
+ }
+ break;
+ case TYFUNC:
+ if (decl.ty.t == TYFUNC)
+ error(&decl.span, "function cannot return function type '%ty'", decl.ty);
+ else if (decl.ty.t == TYARRAY)
+ error(&decl.span, "function cannot return array type '%ty'", decl.ty);
+ if (l->kandr && ccopt.cstd > STDC89 && (ccopt.cstd >= STDC23 || ccopt.pedant))
+ warn(&l->span, "function declaration without a prototype is deprecated");
+ decl.ty = mkfntype(decl.ty, l->npar, l->param, l->kandr, l->variadic);
+ if (l->param != declparamtmp) free(l->param);
+ if (l->prev == &list && l->npar) { /* last */
+ st->pnames = alloccopy(&cm->fnarena, l->pnames, l->npar * sizeof(char *), 0);
+ st->pspans = alloccopy(&cm->fnarena, l->pspans, l->npar * sizeof(struct span), 0);
+ st->pqual = l->pqual ? alloccopy(&cm->fnarena, l->pqual, l->npar, 1) : NULL;
+ decl.inlin = st->fninline;
+ decl.noret = st->fnnoreturn;
+ }
+ if (l->pqual != declpqualtmp) free(l->pqual);
+ if (l->pnames != declpnamestmp) free(l->pnames);
+ if (l->pspans != declpspanstmp) free(l->pspans);
+ if (l->param == declparamtmp) usingdeclparamtmp = 0;
+ decl.qual = 0;
+ break;
+ }
+
+ l->next = declfreelist;
+ declfreelist = l;
+ }
+ if (st->kind != DCASTEXPR && decl.name)
+ decl.span = namespan;
+ return decl;
+}
+
+static void
+pstaticassert(struct comp *cm, struct span *span)
+{
+ struct expr ex;
+ struct token tk, msg = {0};
+
+ /* _Static_assert '(' <expr> [ ',' <strlit> ] ')' ';' */
+ expect(cm, '(', NULL);
+ ex = expr(cm);
+ peek(cm, &tk);
+ if (match(cm, &tk, ',')) {
+ peek(cm, &msg);
+ expect(cm, TKSTRLIT, NULL);
+ }
+ peek(cm, &tk);
+ expect(cm, ')', NULL);
+ expect(cm, ';', NULL);
+
+ joinspan(&span->ex, tk.span.ex);
+ if (!msg.t && ccopt.cstd == STDC11)
+ warn(span, "static assert without message is a C23 extension");
+ if (!eval(&ex, EVINTCONST)) {
+ error(&ex.span, "static assert expression is not an integer constant");
+ } else if (iszero(ex)) {
+ if (msg.t)
+ error(&ex.span, "static assertion failed: %'S", msg.s, msg.len);
+ else
+ error(&ex.span, "static assertion failed");
+ }
+}
+
+static struct decl
+pdecl(struct declstate *st, struct comp *cm) {
+ struct token tk;
+ struct decl decl;
+ bool properdecl = st->kind == DTOPLEVEL || st->kind == DFUNCVAR;
+ bool first = 0;
+
+ assert(!st->funcdef);
+
+ if (st->varini || st->bitf) {
+ memset(&decl, 0, sizeof decl);
+ goto AfterIniBitf;
+ }
+ decl.sym = NULL;
+
+ if (st->base0) goto DeclSpec;
+ if (!st->base.t) {
+ if (properdecl && (match(cm, &tk, TKW_Static_assert) || match(cm, &tk, TKWstatic_assert))) {
+ pstaticassert(cm, &tk.span);
+ return (struct decl){0};
+ }
+ first = 1;
+ if (match(cm, &tk, ';')) {
+ st->empty = 1;
+ return (struct decl){.span = tk.span};
+ }
+
+ DeclSpec:
+ st->base0 = 0;
+ while (attrspec(cm, &st->attr)) ;
+ declspec(st, cm, &decl.span);
+ } else {
+ peek(cm, &tk);
+ decl.span = tk.span;
+ }
+ if (st->scls == SCTYPEDEF) properdecl = 0;
+
+ if (first && st->tagdecl && match(cm, &tk, ';')) {
+ decl = (struct decl) { st->base, st->scls, st->qual, .align = st->align, .span = decl.span };
+ return decl;
+ } else if (st->kind == DFIELD && match(cm, &tk, ':')) {
+ decl = (struct decl) { st->base, st->scls, st->qual, .align = st->align, .span = decl.span };
+ st->bitf = 1;
+ return decl;
+ }
+ decl = declarator(st, cm, decl.span);
+ if (decl.ty.t != TYFUNC && st->fninline)
+ error(&decl.span, "`inline' used on non-function declaration");
+ if (decl.ty.t != TYFUNC && st->fnnoreturn)
+ error(&decl.span, "`_Noreturn' used on non-function declaration");
+ /* trailing attributes */
+ if (st->kind == DTOPLEVEL || st->kind == DFUNCVAR) {
+ while (attrspec(cm, &st->attr)) ;
+ if (match(cm, NULL, TKW__asm__) && expect(cm, '(', NULL)) {
+ peek(cm, &tk);
+ if (expect(cm, TKSTRLIT, "asm symbol name")) {
+ decl.sym = intern_(tk.s, tk.len);
+ }
+ expect(cm, ')', NULL);
+ }
+ while (attrspec(cm, &st->attr)) ;
+ }
+
+ if (properdecl && match(cm, &tk, '=')) {
+ st->varini = 1;
+ return decl;
+ } else if (first && decl.ty.t == TYFUNC && match(cm, &tk, '{')) {
+ st->funcdef = 1;
+ return decl;
+ } else if (st->kind == DFIELD && match(cm, &tk, ':')) {
+ st->bitf = 1;
+ return decl;
+ }
+
+AfterIniBitf:
+ st->varini = st->bitf = 0;
+ st->more = 0;
+ if (st->kind != DCASTEXPR && st->kind != DFUNCPARAM) {
+ if (match(cm, &tk, ','))
+ st->more = 1;
+ else expect(cm, st->kind == DFUNCPARAM ? ')' : ';', "or `,'");
+ }
+
+ return decl;
+}
+
+/*****************/
+/* IR Generation */
+/*****************/
+
+static inline union ref
+exprvalue(struct function *fn, const struct expr *ex)
+{
+ return compileexpr(fn, ex, /*discard*/ 0);
+}
+static inline void
+expreffects(struct function *fn, const struct expr *ex)
+{
+ compileexpr(fn, ex, /*discard*/ 1);
+}
+
+static void
+structcopy(struct function *fn, union type ty, union ref dst, union ref src)
+{
+ union irtype typ = mkirtype(ty);
+ addinstr(fn, mkarginstr(typ, dst));
+ addinstr(fn, mkarginstr(typ, src));
+ addinstr(fn, mkintrin(INstructcopy, 0, 2));
+}
+
+static union ref
+structreturn(struct function *fn, const struct expr *src)
+{
+ return expraddr(fn, src);
+}
+
+static union ref compilecall(struct function *fn, const struct expr *ex);
+
+static internstr
+mkhiddensym(const char *fnname, const char *name, int id)
+{
+ char buf[200];
+ struct wbuf wbuf = MEMBUF(buf, sizeof buf);
+ assert(id > 0);
+ if (fnname)
+ bfmt(&wbuf, "%s.%s.%d", fnname, name, id-1);
+ else
+ bfmt(&wbuf, "%s.%d", name, id-1);
+ ioputc(&wbuf, 0);
+ assert(!wbuf.err);
+ return intern(buf);
+}
+
+static void geninit(struct function *fn, union type t, union ref dst, const struct expr *src);
+static union ref condexprvalue(struct function *fn, const struct expr *ex, bool discard);
+
+union ref
+expraddr(struct function *fn, const struct expr *ex)
+{
+ struct decl *decl;
+ union ref r;
+
+ switch (ex->t) {
+ case ESYM:
+ decl = &declsbuf.p[ex->decl];
+ assert(decl != NULL);
+ switch (decl->scls) {
+ case SCAUTO: case SCREGISTER:
+ assert(decl->id >= 0);
+ return mkref(RTMP, decl->id);
+ case SCEXTERN: case SCNONE: case SCSTATIC:
+ return mksymref(decl->sym, (SFUNC & -(decl->ty.t == TYFUNC)) | (SLOCAL & -(decl->scls == SCSTATIC || decl->isdef)));
+ default:
+ assert(0);
+ }
+ break;
+ case ESSYMREF:
+ return irbinop(fn, Oadd, KPTR,
+ mksymref(ex->ssym.sym, (SFUNC & -ex->ssym.func) | (SLOCAL & -ex->ssym.local)),
+ mkintcon(KPTR, ex->ssym.off));
+ case ESTRLIT:
+ /* XXX endian for wide strs */
+ return mkdatref(NULL, ex->ty, typesize(ex->ty), typealign(ex->ty), ex->s.p, ex->s.n * typesize(typechild(ex->ty)), /*deref*/0, fn != NULL);
+ case EDEREF:
+ return exprvalue(fn, ex->sub);
+ case EGETF:
+ r = expraddr(fn, ex->sub);
+ assert(ex->fld.bitsiz == 0);
+ return irbinop(fn, Oadd, KPTR, r, mkintcon(KI32, ex->fld.off));
+ case ESET:
+ assert(isagg(ex->ty));
+ r = expraddr(fn, &ex->sub[1]);
+ structcopy(fn, ex->ty, expraddr(fn, &ex->sub[0]), r);
+ return r;
+ case ECALL:
+ assert(isagg(ex->ty));
+ return compilecall(fn, ex);
+ case EVAARG:
+ assert(isagg(ex->ty));
+ return builtin_va_arg_comp(fn, ex, 0);
+ case EINIT:
+ if (fn) {
+ /* compound literal, allocate temp */
+ r = addinstr(fn, mkalloca(typesize(ex->ty), typealign(ex->ty)));
+ geninit(fn, ex->ty, r, ex);
+ return r;
+ } else {
+ /* emit static dat */
+ static int id;
+ struct initparser ip[1] = {0};
+ union type ty = ex->ty;
+ internstr sym = mkhiddensym(NULL, ".LC", ++id);
+ ip->sec = Sdata; /* TODO put in rodata if possible */
+ ip->ev = EVSTATICINI;
+ assert(!isincomplete(ty));
+ ip->off = objnewdat(sym, ip->sec, 0, typesize(ty), typealign(ty));
+ if (!iniwriterec(NULL, ip, 0, (struct expr *)ex))
+ error(&ex->span, "cannot not evaluate expression statically");
+ return mksymref(sym, 0);
+ }
+ case ESEQ:
+ expreffects(fn, &ex->sub[0]);
+ return expraddr(fn, &ex->sub[1]);
+ case ECOND:
+ assert(isagg(ex->ty));
+ return condexprvalue(fn, ex, 0);
+ default:
+ assert(!"lvalue?>");
+ }
+
+}
+
+static union ref
+genload(struct function *fn, union type t, union ref ref, bool volatyl)
+{
+ struct instr ins = {0};
+
+ assert(isscalar(t));
+ ins.cls = type2cls[scalartypet(t)];
+ assert(ins.cls);
+ switch (typesize(t)) {
+ case 1: ins.op = issigned(t) ? Oloads8 : Oloadu8; break;
+ case 2: ins.op = issigned(t) ? Oloads16 : Oloadu16; break;
+ case 4: ins.op = isflt(t) ? Oloadf32 : issigned(t) ? Oloads32 : Oloadu32; break;
+ case 8: ins.op = isflt(t) ? Oloadf64 : Oloadi64; break;
+ default: assert(0);
+ }
+ ins.l = ref;
+ ins.keep = volatyl;
+ return addinstr(fn, ins);
+}
+
+static union ref
+genstore(struct function *fn, union type t, union ref ptr, union ref val)
+{
+ struct instr ins = {0};
+
+ assert(isscalar(t));
+ switch (typesize(t)) {
+ case 1: ins.op = Ostorei8; break;
+ case 2: ins.op = Ostorei16; break;
+ case 4: ins.op = isflt(t) ? Ostoref32 : Ostorei32; break;
+ case 8: ins.op = isflt(t) ? Ostoref64 : Ostorei64; break;
+ default: assert(0);
+ }
+ ins.l = ptr;
+ ins.r = val;
+ return addinstr(fn, ins);
+}
+
+static void genbitfstore(struct function *fn, const union type ty, union ref addr,
+ const struct exgetfld *fld, union ref tmp, union ref val);
+
+static void
+geninit(struct function *fn, union type t, union ref dst, const struct expr *src)
+{
+ union ref adr;
+ if (src->t == EINIT) {
+ struct init *ini = src->init;
+ uint siz = typesize(t);
+ uint align = typealign(t);
+ struct bitset azero[1] = {0};
+
+ if (BSSIZE(siz) <= countof(ini->zero)) {
+ for (int i = 0; i < siz; i += align) {
+ for (int j = 0; j < align; ++j) {
+ if (bstest(ini->zero, i + j)) {
+ bsset(azero, i);
+ break;
+ }
+ }
+ }
+ if (bscount(azero, countof(azero)) < 32) {
+ /* write individual zeros at non initialized gaps */
+ for (uint i = 0; bsiter(&i, azero, countof(azero)) && i < siz; i += align) {
+ adr = irbinop(fn, Oadd, KPTR, dst, mkref(RICON, i));
+ addinstr(fn, mkinstr(Ostorei8 + ilog2(align), 0, .l = adr, .r = ZEROREF));
+ }
+ } else {
+ goto Memset0;
+ }
+ } else Memset0: {
+ /* memset(dst,0,siz) */
+ /* TODO make it into an intrinsic */
+ struct instr call = { Ocall, KPTR };
+ addinstr(fn, mkarginstr(cls2type(KPTR), dst));
+ addinstr(fn, mkarginstr(cls2type(KI32), ZEROREF));
+ addinstr(fn, mkarginstr(cls2type(type2cls[targ_sizetype]), mkintcon(type2cls[targ_sizetype], siz)));
+ call.l = mksymref(istr_memset, 1);
+ call.r = mkcallarg(cls2type(KPTR), 3, -1);
+ addinstr(fn, call);
+ }
+ for (struct initval *val = ini->vals; val; val = val->next) {
+ uint off = val->off;
+ struct expr *ex = &val->ex;
+ adr = irbinop(fn, Oadd, KPTR, dst, mkref(RICON, off));
+ if (ex->t == EINIT || ex->t == ESTRLIT) {
+ geninit(fn, ex->ty, adr, ex);
+ } else if (isagg(ex->ty)) {
+ structcopy(fn, ex->ty, adr, expraddr(fn, ex));
+ } else if (!val->bitsiz) {
+ genstore(fn, ex->ty, adr, exprvalue(fn, ex));
+ } else {
+ union ref q = exprvalue(fn, ex);
+ genbitfstore(fn, ex->ty, adr, &(struct exgetfld){0, val->bitsiz, val->bitoff}, NOREF, q);
+ }
+ }
+ } else if (src->t == ESTRLIT) {
+ union type ctyp = typechild(src->ty);
+ uint csiz = typesize(ctyp);
+ adr = dst;
+ for (uint i = 0; i < src->s.n; ++i) {
+ if (csiz == 1)
+ genstore(fn, ctyp, adr, mkref(RICON, src->s.p[i]));
+ else if (csiz == 2)
+ genstore(fn, ctyp, adr, mkref(RICON, src->s.w16[i]));
+ else
+ genstore(fn, ctyp, adr, mkintcon(KI32, src->s.w32[i]));
+ adr = irbinop(fn, Oadd, KPTR, dst, mkref(RICON, (i+1)*csiz));
+ }
+ genstore(fn, ctyp, adr, ZEROREF); /* null term */
+ } else assert(0);
+}
+
+static bool
+isboollike(struct function *fn, union ref r)
+{
+ struct instr *ins;
+ if (r.t == RICON && (r.i == 0 || r.i == 1)) return 1;
+ if (r.t != RTMP) return 0;
+ ins = &instrtab[r.i];
+ if (oiscmp(ins->op)) /* these instrs already have output range of [0,1] */
+ return 1;
+ if (ins->op == Ophi) { /* check if all the phi args are boollike */
+ struct block *blk;
+ union ref *phi = NULL;
+ for (blk = fn->curblk; phi == NULL; blk = blk->lprev) {
+ /* find blk that defines phi */
+ assert(blk != fn->entry);
+ for (int i = 0; i < blk->phi.n; ++i){
+ if (blk->phi.p[i] == r.i) {
+ phi = phitab.p[ins->l.i];
+ break;
+ }
+ }
+ }
+ for (int i = 0; i < blk->npred; ++i) {
+ if (!isboollike(fn, phi[i])) {
+ return 0;
+ }
+ }
+ return 1;
+ }
+ if (in_range(ins->op, Oand, Oxor))
+ return isboollike(fn, ins->l) && isboollike(fn, ins->r);
+ if (ins->op == Ocopy || in_range(ins->op, Oexts8, Oextu32))
+ return isboollike(fn, ins->l);
+ if (ins->op == Oparam)
+ return typedata[fn->fnty.dat].param[ins->l.i].t == TYBOOL;
+ return 0;
+}
+
+union ref
+scalarcvt(struct function *fn, union type to, union type from, union ref ref)
+{
+ enum irclass kto = type2cls[scalartypet(to)], kfrom = type2cls[scalartypet(from)];
+ enum op op;
+ if (to.bits == from.bits) return ref;
+ assert(kto && kfrom);
+ if (kto == kfrom && to.t != TYBOOL) return ref;
+
+ if (kisflt(kto) || kisflt(kfrom)) {
+ if (ref.t == RICON) {
+ assert(kisflt(kto) && kisint(kfrom));
+ return mkfltcon(kto, kto == KF32 ? (float)ref.i : (double)ref.i);
+ }
+ if (kisflt(kto) && kfrom == KI32) op = issigned(from) ? Ocvts32f : Ocvtu32f;
+ else if (to.t == TYBOOL && kisflt(kfrom)) return irbinop(fn, Oneq, kfrom, ref, mkfltcon(kfrom, 0.0));
+ else if (kisflt(kto) && kfrom == KI64) op = issigned(from) ? Ocvts64f : Ocvtu64f;
+ else if (kto == KF64 && kfrom == KF32) op = Ocvtf32f64;
+ else if (kto == KF32 && kfrom == KF64) op = Ocvtf64f32;
+ else if (kfrom == KF32) op = issigned(to) ? Ocvtf32s : Ocvtf32u;
+ else if (kfrom == KF64) op = issigned(to) ? Ocvtf64s : Ocvtf64u;
+ else assert(0);
+ } else {
+ if (to.t == TYBOOL) {
+ if (from.t == TYBOOL) return ref;
+ if (isboollike(fn, ref))
+ return kfrom == KI32 ? ref : scalarcvt(fn, mktype(TYINT), from, ref);
+ return irbinop(fn, Oneq, kfrom, ref, ZEROREF);
+ }
+ else if (kfrom == KI32 && issigned(from)) op = Oexts32;
+ else if (kfrom == KI32) op = Oextu32;
+ else if (kto == KI32 && isintcon(ref))
+ return issigned(to) ? mkintcon(kto, (int)intconval(ref)) : mkintcon(kto, (uint)intconval(ref));
+ else op = Ocopy;
+ }
+ return irunop(fn, op, kto, ref);
+}
+
+static union ref
+narrow(struct function *fn, enum irclass to, union type t, union ref ref, uint bitsiz)
+{
+ enum typetag tt = scalartypet(t);
+ assert(isscalar(t));
+ if (targ_primsizes[tt] < cls2siz[to]) {
+ enum op op;
+ if (isfltt(tt)) {
+ assert(to == KF32 && tt >= TYDOUBLE);
+ op = Ocvtf64f32;
+ } else {
+ static const enum op ext[5][2] = {
+ [1] = {Oextu8, Oexts8}, [2] = {Oextu16, Oexts16}, [4] = {Oextu32, Oexts32}
+ };
+ op = ext[targ_primsizes[tt]][issignedt(tt)];
+ }
+ ref = irunop(fn, op, to, ref);
+ }
+ if (bitsiz) {
+ assert(kisint(to) && isintt(tt) && bitsiz < 8*targ_primsizes[tt]);
+ if (!issignedt(tt)) {
+ ref = irbinop(fn, Oand, to, ref, mkintcon(to, (1ull<<bitsiz)-1));
+ } else {
+ uint sh = 8*cls2siz[to] - bitsiz;
+ ref = irbinop(fn, Oshl, to, ref, mkref(RICON, sh));
+ ref = irbinop(fn, Osar, to, ref, mkref(RICON, sh));
+ }
+ }
+ return ref;
+}
+
+union ref
+genptroff(struct function *fn, enum op op, uint siz, union ref ptr,
+ union type t, union ref idx)
+{
+ uint cls = type2cls[targ_sizetype];
+ union ref off;
+ assert(siz);
+
+ idx = scalarcvt(fn, mktype(targ_sizetype), t, idx);
+ if (siz == 1) off = idx;
+ else if (idx.t == RICON) {
+ if (op == Osub) op = Oadd, idx.i = -idx.i;
+ off = mkintcon(cls, idx.i * (int)siz);
+ } else {
+ off = irbinop(fn, Omul, cls, idx, mkintcon(cls, siz));
+ }
+ assert(in_range(op, Oadd, Osub));
+ return irbinop(fn, op, KPTR, ptr, off);
+}
+
+union ref
+genptrdiff(struct function *fn, uint siz, union ref a, union ref b)
+{
+ uint cls = type2cls[targ_ptrdifftype];
+ assert(siz > 0);
+ a = irbinop(fn, Osub, cls, a, b);
+ if (siz == 1) return a;
+ else if (ispo2(siz))
+ return irbinop(fn, Osar, cls, a, mkintcon(cls, ilog2(siz)));
+ else
+ return irbinop(fn, Odiv, cls, a, mkintcon(cls, siz));
+}
+
+/* used to emit the jumps in an in if (), while (), etc condition */
+static void
+condjump(struct function *fn, const struct expr *ex, struct block *tr, struct block *fl)
+{
+ struct block *next, *next2;
+Recur:
+ for (; ex->t == ESEQ; ex = &ex->sub[1])
+ expreffects(fn, &ex->sub[0]);
+ if (ex->t == ELOGAND) {
+ next = newblk(fn);
+ condjump(fn, &ex->sub[0], next, fl);
+ useblk(fn, next);
+ ex = &ex->sub[1];
+ goto Recur;
+ } else if (ex->t == ELOGIOR) {
+ next = newblk(fn);
+ condjump(fn, &ex->sub[0], tr, next);
+ useblk(fn, next);
+ ex = &ex->sub[1];
+ goto Recur;
+ } else if (ex->t == ECOND) {
+ next = newblk(fn);
+ next2 = newblk(fn);
+ condjump(fn, &ex->sub[0], next, next2);
+ useblk(fn, next);
+ condjump(fn, &ex->sub[1], tr, fl);
+ useblk(fn, next2);
+ condjump(fn, &ex->sub[2], tr, fl);
+ } else if (ex->t == ELOGNOT) {
+ Negate:
+ /* swap tr,fl */
+ next = tr;
+ tr = fl;
+ fl = next;
+ ex = &ex->sub[0];
+ goto Recur;
+ } else if (ex->t == EEQU && isnullpo(&ex->sub[1])) { /* == 0 */
+ goto Negate;
+ } else if (ex->t == ENEQ && isnullpo(&ex->sub[1])) { /* != 0 */
+ ex = &ex->sub[0];
+ goto Recur;
+ } else {
+ putcondbranch(fn, exprvalue(fn, ex), tr, fl);
+ }
+}
+
+struct condphis {
+ union type typ;
+ vec_of(union ref) ref;
+};
+
+static void
+condexprrec(struct function *fn, const struct expr *ex, struct condphis *phis, struct block *end)
+{
+Recur:
+ for (; ex->t == ESEQ; ex = &ex->sub[1])
+ expreffects(fn, &ex->sub[0]);
+ int prevpred = end->npred;
+ if (ex->t == ELOGAND) {
+ struct block *tr = newblk(fn);
+ condjump(fn, &ex->sub[0], tr, end);
+ assert(prevpred <= end->npred);
+ if (phis) for (int n = end->npred - prevpred; n > 0; --n) {
+ vpush(&phis->ref, mkref(RICON, 0));
+ }
+ useblk(fn, tr);
+ ex = &ex->sub[1];
+ goto Recur;
+ } else if (ex->t == ELOGIOR) {
+ struct block *fl = newblk(fn);
+ condjump(fn, &ex->sub[0], end, fl);
+ assert(prevpred <= end->npred);
+ if (phis) for (int n = end->npred - prevpred; n > 0; --n) {
+ vpush(&phis->ref, mkref(RICON, 1));
+ }
+ useblk(fn, fl);
+ ex = &ex->sub[1];
+ goto Recur;
+ } else if (ex->t == ECOND) {
+ struct block *tr = newblk(fn), *fl = newblk(fn);
+ condjump(fn, &ex->sub[0], tr, fl);
+ useblk(fn, tr);
+ condexprrec(fn, &ex->sub[1], phis, end);
+ useblk(fn, fl);
+ ex = &ex->sub[2];
+ goto Recur;
+ } else {
+ if (!phis) {
+ expreffects(fn, ex);
+ } else {
+ union ref val = exprvalue(fn, ex);
+ if (isscalar(phis->typ))
+ val = scalarcvt(fn, phis->typ, ex->ty, val);
+ else assert(ex->ty.bits == phis->typ.bits);
+ vpush(&phis->ref, val);
+ }
+ putbranch(fn, end);
+ }
+}
+
+/* the naive way to generate something like a ? b : c ? d : e, uses multiple phis,
+ * this code reduces such nested conditional expressions into one phi */
+static union ref
+condexprvalue(struct function *fn, const struct expr *ex, bool discard)
+{
+ union ref refbuf[8];
+ struct condphis phis = { ex->t == ECOND ? ex->ty : mktype(TYBOOL), VINIT(refbuf, countof(refbuf)) };
+ struct block *dst = newblk(fn);
+ condexprrec(fn, ex, discard ? NULL : &phis, dst);
+ useblk(fn, dst);
+ if (discard) return NOREF;
+ enum irclass k;
+ if (isscalar(ex->ty)) {
+ k = type2cls[scalartypet(ex->ty)];
+ assert(k);
+ } else {
+ assert(isagg(ex->ty) || isptrcvt(ex->ty));
+ k = KPTR;
+ }
+ union ref r = addphi(fn, k, phis.ref.p);
+ vfree(&phis.ref);
+ return r;
+}
+
+static union ref
+compilecall(struct function *fn, const struct expr *ex)
+{
+ struct instr ins = {0};
+ struct expr *sub = ex->sub;
+ const struct typedata *td = &typedata[sub[0].ty.dat];
+ struct instr insnsbuf[10];
+ vec_of(struct instr) insns = VINIT(insnsbuf, countof(insnsbuf));
+
+ if (sub[0].t == ESYM && declsbuf.p[sub[0].decl].isbuiltin) {
+ return declsbuf.p[sub[0].decl].builtin->comp(fn, (struct expr *)ex, 0);
+ }
+ ins.op = Ocall;
+ if (isagg(ex->ty)) {
+ ins.cls = KPTR;
+ } else {
+ assert(isscalar(ex->ty) || ex->ty.t == TYVOID);
+ ins.cls = type2cls[scalartypet(ex->ty)];
+ assert(ins.cls || ex->ty.t == TYVOID);
+ }
+ ins.l = exprvalue(fn, &sub[0]);
+ for (int i = 0; i < ex->narg; ++i) {
+ struct expr *arg = &sub[i+1];
+ union type ty = i < td->nmemb ? td->param[i] : argpromote(arg->ty);
+ union ref r = scalarcvt(fn, ty, typedecay(arg->ty), exprvalue(fn, arg));
+ vpush(&insns, mkarginstr(mkirtype(ty), r));
+ }
+ for (int i = 0; i < insns.n; ++i)
+ addinstr(fn, insns.p[i]);
+ vfree(&insns);
+ ins.r = mkcallarg(mkirtype(ex->ty), ex->narg, td->variadic ? td->nmemb : td->kandr ? 0 : -1);
+ union ref r = addinstr(fn, ins);
+ if (sub[0].t == ESYM && declsbuf.p[sub[0].decl].noret) /* trap if noreturn func returns */
+ puttrap(fn);
+ return r;
+}
+
+static union ref
+genbitfload(struct function *fn, union ref *tmpval, const union type ty, union ref *addr,
+ const struct exgetfld *fld, bool volatyl)
+{
+ enum irclass k = type2cls[scalartypet(ty)];
+ uint off = fld->off, bitsiz = fld->bitsiz, bitoff = fld->bitoff;
+ union ref tmp;
+ uvlong mask;
+
+ assert(k);
+ *addr = irbinop(fn, Oadd, KPTR, *addr, mkintcon(KI32, off));
+ tmp = genload(fn, ty, *addr, volatyl);
+ if (tmpval) *tmpval = tmp;
+ if (!issigned(ty)) {
+ /* shift right and mask */
+ tmp = irbinop(fn, Oslr, k, tmp, mkref(RICON, bitoff));
+ if (bitsiz < 8*typesize(ty)) {
+ mask = bitsiz == 64 ? -1ull : (1ull << bitsiz) - 1;
+ tmp = irbinop(fn, Oand, k, tmp, mkintcon(k, mask));
+ }
+ } else {
+ /* shift left and shift right arithmetic to propagate sign bit */
+ int sh = 8*cls2siz[k] - bitsiz - bitoff;
+ tmp = irbinop(fn, Oshl, k, tmp, mkref(RICON, sh));
+ sh += bitoff;
+ tmp = irbinop(fn, Osar, k, tmp, 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[scalartypet(ty)];
+ uint off = fld->off, bitsiz = fld->bitsiz, bitoff = fld->bitoff;
+ uint bittypesize = 8*typesize(ty);
+ uvlong mask;
+
+ assert(k);
+ if (!tmp.bits) {
+ addr = irbinop(fn, Oadd, KPTR, addr, mkintcon(KPTR, off));
+ tmp = genload(fn, ty, addr, 0);
+ }
+ mask = (bitsiz == 64 ? -1ull : (1ull << bitsiz) - 1) << bitoff;
+
+ /* mask out bits in existing container */
+ tmp = irbinop(fn, Oand, k, tmp, mkintcon(k, ~mask));
+
+ /* shift and mask source value */
+ if (isintcon(val)) {
+ val = mkintcon(k, ((uvlong)intconval(val) << bitoff) & mask);
+ } else {
+ val = irbinop(fn, Oshl, k, val, mkref(RICON, bitoff));
+ if (bitsiz < bittypesize)
+ val = irbinop(fn, Oand, k, val, mkintcon(k, mask));
+ }
+ /* combine and write */
+ if (bitsiz < bittypesize)
+ val = irbinop(fn, Oior, k, tmp, val);
+ genstore(fn, ty, addr, val);
+}
+
+static bool
+knowntruthy(bool *t, struct expr *ex)
+{
+ if (!eval(ex, EVFOLD)) return 0;
+
+ switch (ex->t) {
+ default: assert(0 && "!scalar?");
+ case ENUMLIT:
+ *t = isflt(ex->ty) ? ex->f != 0.0 : ex->u != 0;
+ break;
+ case ESTRLIT: case ESSYMREF:
+ /* string literals & symbol addresses are always truthy */
+ *t = 1;
+ break;
+ }
+ return 1;
+}
+
+union ref
+compileexpr(struct function *fn, const struct expr *ex, bool discard)
+{
+ union type ty;
+ union ref l, r, q, adr;
+ uint bitsiz;
+ enum op op;
+ enum irclass cls = type2cls[scalartypet(ex->ty)];
+ int swp = 0;
+ struct expr *sub;
+
+ //eval((struct expr *)ex, EVFOLD);
+ sub = ex->sub;
+
+ if (ex->ty.t != TYVOID && !isscalar(ex->ty)) {
+ /* fn & array designators evaluate to their address;
+ * so do aggregates for the purpose of code generation */
+ if (isagg(ex->ty) && isincomplete(ex->ty))
+ error(&ex->span, "use of incomplete type '%ty'", ex->ty);
+ return expraddr(fn, ex);
+ }
+ switch (ex->t) {
+ case ENUMLIT:
+ if (discard) return NOREF;
+ if (isflt(ex->ty))
+ return mkfltcon(cls, ex->f);
+ return mkintcon(cls, ex->i);
+ case ESYM:
+ if (discard && !(ex->qual & QVOLATILE)) return NOREF;
+ return genload(fn, ex->ty, expraddr(fn, ex), ex->qual & QVOLATILE);
+ case ESSYMREF:
+ return expraddr(fn, ex);
+ case EVAARG:
+ return builtin_va_arg_comp(fn, ex, discard);
+ case EGETF:
+ if (discard && !(ex->qual & QVOLATILE)) return NOREF;
+ if (ex->fld.bitsiz) {
+ /* bit-field */
+ r = expraddr(fn, ex->sub);
+ return genbitfload(fn, NULL, ex->ty, &r, &ex->fld, ex->qual & QVOLATILE);
+ }
+ return genload(fn, ex->ty, expraddr(fn, ex), ex->qual & QVOLATILE);
+ case ECAST:
+ if (ex->ty.t == TYVOID) {
+ expreffects(fn, sub);
+ return NOREF;
+ }
+ /* fallthru */
+ case EPLUS:
+ r = compileexpr(fn, sub, discard);
+ if (discard) return NOREF;
+ r = scalarcvt(fn, ex->ty, sub->ty, r);
+ if (isint(ex->ty) && (typesize(ex->ty) < typesize(sub->ty) || issigned(ex->ty) != issigned(sub->ty)))
+ return narrow(fn, type2cls[scalartypet(ex->ty)], ex->ty, r, 0);
+ return r;
+ case ENEG:
+ op = Oneg;
+ goto Unary;
+ case ECOMPL:
+ op = Onot;
+ Unary:
+ l = compileexpr(fn, sub, discard);
+ if (discard) return NOREF;
+ l = scalarcvt(fn, ex->ty, sub->ty, l);
+ return irunop(fn, op, cls, l);
+ case ELOGNOT:
+ for (; sub->t == ELOGNOT; ex = sub, sub = sub->sub)
+ swp ^= 1;
+ op = Oequ + swp;
+ l = compileexpr(fn, sub, discard);
+ if (discard) return NOREF;
+ l = scalarcvt(fn, ex->ty, sub->ty, l);
+ r = mkintcon(cls, 0);
+ return irbinop(fn, op, cls, l, r);
+ case EDEREF:
+ discard &= (ex->qual & QVOLATILE) == 0;
+ r = compileexpr(fn, sub, discard);
+ if (discard) return NOREF;
+ return genload(fn, ex->ty, r, ex->qual & QVOLATILE);
+ case EADDROF:
+ return expraddr(fn, sub);
+ case EMUL:
+ op = Omul;
+ goto BinArith;
+ case EDIV:
+ op = isunsigned(ex->ty) ? Oudiv : Odiv;
+ goto BinArith;
+ case EREM:
+ op = issigned(ex->ty) ? Orem : Ourem;
+ goto BinArith;
+ case EBAND:
+ op = Oand;
+ goto BinArith;
+ case EXOR:
+ op = Oxor;
+ goto BinArith;
+ case EBIOR:
+ op = Oior;
+ goto BinArith;
+ case ESHL:
+ op = Oshl;
+ goto BinArith;
+ case ESHR:
+ op = issigned(ex->ty) ? Osar : Oslr;
+ goto BinArith;
+ case ESUB:
+ op = Osub;
+ goto BinArith;
+ case EADD:
+ op = Oadd;
+ BinArith:
+ l = compileexpr(fn, &sub[0], discard);
+ r = compileexpr(fn, &sub[1], discard);
+ if (discard) return NOREF;
+ if (op == Osub && isptrcvt(sub[0].ty) && isptrcvt(sub[1].ty)) {
+ /* ptr - ptr */
+ return genptrdiff(fn, typesize(typechild(sub[0].ty)), l, r);
+ } else if ((op != Oadd && op != Osub) || cls != KPTR) {
+ /* num OP num */
+ l = scalarcvt(fn, ex->ty, sub[0].ty, l);
+ r = scalarcvt(fn, ex->ty, sub[1].ty, r);
+ } else {
+ assert(isptrcvt(sub[0].ty));
+ /* ptr +/- num */
+ return genptroff(fn, op, typesize(typechild(sub[0].ty)), l, sub[1].ty, r);
+ }
+ return irbinop(fn, op, cls, l, r);
+ case EPOSTINC:
+ case EPOSTDEC:
+ op = ex->t == EPOSTINC ? Oadd : Osub;
+ if (ex->ty.t == TYPTR)
+ r = mkintcon(type2cls[targ_sizetype], typesize(typechild(ex->ty)));
+ else
+ r = isflt(ex->ty) ? mkfltcon(type2cls[ex->ty.t], 1.0) : mkref(RICON, 1);
+ bitsiz = 0;
+ if (sub[0].t == EGETF && (bitsiz = sub->fld.bitsiz)) {
+ union ref tmp;
+ adr = expraddr(fn, &sub[0].sub[0]);
+ l = genbitfload(fn, &tmp, sub[0].ty, &adr, &sub[0].fld, sub[0].qual & QVOLATILE);
+ q = irbinop(fn, op, cls, l, r);
+ genbitfstore(fn, sub[0].ty, adr, &sub[0].fld, tmp, q);
+ } else {
+ adr = expraddr(fn, sub);
+ l = genload(fn, sub->ty, adr, sub->qual & QVOLATILE);
+ q = irbinop(fn, op, cls, l, r);
+ genstore(fn, sub->ty, adr, q);
+ }
+ return discard ? NOREF : l;
+ case EPREINC:
+ case EPREDEC:
+ op = ex->t == EPREINC ? Oadd : Osub;
+ if (ex->ty.t == TYPTR)
+ r = mkintcon(type2cls[targ_sizetype], typesize(typechild(ex->ty)));
+ else
+ r = isflt(ex->ty) ? mkfltcon(type2cls[ex->ty.t], 1.0) : mkref(RICON, 1);
+ if (sub[0].t == EGETF && (bitsiz = sub->fld.bitsiz)) {
+ ty = ex->ty;
+ goto CompoundBitf;
+ }
+ adr = expraddr(fn, sub);
+ l = genload(fn, sub->ty, adr, sub->qual & QVOLATILE);
+ q = irbinop(fn, op, cls, l, r);
+ genstore(fn, sub->ty, adr, q);
+ if (discard) return NOREF;
+ return narrow(fn, cls, ex->ty, q, 0);
+ case EEQU:
+ op = Oequ;
+ goto Cmp;
+ case ENEQ:
+ op = Oneq;
+ goto Cmp;
+ case ELTH:
+ op = Olth;
+ goto Cmp;
+ case ELTE:
+ op = Olte;
+ goto Cmp;
+ case EGTH:
+ op = Ogth;
+ goto Cmp;
+ case EGTE:
+ op = Ogte;
+ Cmp:
+ ty = cvtarith(sub[0].ty, sub[1].ty);
+ if (!ty.t) ty.t = TYPTR;
+ if (isunsigned(ty) && in_range(op, Olth, Ogte))
+ op += Oulth - Olth;
+ l = compileexpr(fn, &sub[0], discard);
+ r = compileexpr(fn, &sub[1], discard);
+ if (discard) return NOREF;
+ l = scalarcvt(fn, ty, sub[0].ty, l);
+ r = scalarcvt(fn, ty, sub[1].ty, r);
+ cls = type2cls[ty.t];
+ return irbinop(fn, op, cls, l, r);
+ case ESET:
+ assert(isscalar(ex->ty));
+ q = scalarcvt(fn, sub[0].ty, sub[1].ty, exprvalue(fn, &sub[1]));
+ if (sub[0].t == EGETF && (bitsiz = sub[0].fld.bitsiz)) {
+ /* bit-field */
+ adr = expraddr(fn, &sub[0].sub[0]);
+ genbitfstore(fn, ex->ty, adr, &sub[0].fld, NOREF, q);
+ } else {
+ bitsiz = 0;
+ adr = expraddr(fn, &sub[0]);
+ genstore(fn, ex->ty, adr, q);
+ }
+ if (discard) return NOREF;
+ return bitsiz ? narrow(fn, cls, sub[0].ty, q, bitsiz) : q;
+ case ESETMUL:
+ op = Omul;
+ goto Compound;
+ case ESETDIV:
+ op = isunsigned(ex->ty) ? Oudiv : Odiv;
+ goto Compound;
+ case ESETREM:
+ op = issigned(ex->ty) ? Orem : Ourem;
+ goto Compound;
+ case ESETAND:
+ op = Oand;
+ goto Compound;
+ case ESETXOR:
+ op = Oxor;
+ goto Compound;
+ case ESETIOR:
+ op = Oior;
+ goto Compound;
+ case ESETSHL:
+ op = Oshl;
+ goto Compound;
+ case ESETSHR:
+ op = issigned(ex->ty) ? Osar : Oslr;
+ goto Compound;
+ case ESETSUB:
+ op = Osub;
+ goto Compound;
+ case ESETADD:
+ op = Oadd;
+ Compound:
+ ty = in_range(ex->t, ESETSHL, ESETSHR) ? mktype(intpromote(ex->ty.t))
+ : cvtarith(sub[0].ty, sub[1].ty);
+ r = exprvalue(fn, &sub[1]);
+ if (sub[0].t == EGETF && (bitsiz = sub[0].fld.bitsiz)) {
+ /* bit-field */
+ union ref tmp;
+ CompoundBitf:
+ adr = expraddr(fn, &sub[0].sub[0]);
+ l = genbitfload(fn, &tmp, sub[0].ty, &adr, &sub[0].fld, sub[0].qual & QVOLATILE);
+ q = irbinop(fn, op, cls, l, r);
+ genbitfstore(fn, sub[0].ty, adr, &sub[0].fld, tmp, q);
+ } else {
+ bitsiz = 0;
+ adr = expraddr(fn, &sub[0]);
+ l = genload(fn, ex->ty, adr, ex->qual & QVOLATILE);
+ if ((op != Oadd && op != Osub) || cls != KPTR) {
+ l = scalarcvt(fn, ty, sub[0].ty, l);
+ r = scalarcvt(fn, ty, sub[1].ty, r);
+ q = irbinop(fn, op, type2cls[ty.t], l, r);
+ q = scalarcvt(fn, ex->ty, ty, q);
+ } else {
+ q = genptroff(fn, op, typesize(typechild(ex->ty)), l, sub[1].ty, r);
+ }
+ genstore(fn, ex->ty, adr, q);
+ }
+ if (discard) return NOREF;
+ return bitsiz ? narrow(fn, cls, ex->ty, q, bitsiz) : q;
+ case ECALL:
+ r = compilecall(fn, ex);
+ if (isint(ex->ty))
+ return narrow(fn, cls, ex->ty, r, 0);
+ return r;
+ case ECOND:
+ for (bool c; knowntruthy(&c, &ex->sub[0]);) {
+ r = compileexpr(fn, &ex->sub[2-c], discard);
+ if (discard) return NOREF;
+ return scalarcvt(fn, ex->ty, ex->sub[2-c].ty, r);
+ }
+
+ if (ex->ty.t == TYVOID || discard) {
+ struct block *tr, *fl, *end;
+ condjump(fn, &sub[0], tr = newblk(fn), fl = newblk(fn));
+ useblk(fn, tr);
+ expreffects(fn, &sub[1]);
+ end = newblk(fn);
+ if (fn->curblk)
+ putbranch(fn, end);
+ useblk(fn, fl);
+ expreffects(fn, &sub[2]);
+ if (fn->curblk)
+ putbranch(fn, end);
+ useblk(fn, end);
+ return NOREF;
+ }
+ return condexprvalue(fn, ex, discard);
+ case ELOGAND:
+ case ELOGIOR:
+ for (bool c; knowntruthy(&c, &ex->sub[0]);) {
+ c ^= ex->t == ELOGIOR;
+ r = compileexpr(fn, &ex->sub[c], discard);
+ if (discard) return NOREF;
+ return scalarcvt(fn, mktype(TYBOOL), ex->sub[c].ty, r);
+ }
+ return condexprvalue(fn, ex, discard);
+ case ESEQ:
+ expreffects(fn, &sub[0]);
+ return compileexpr(fn, &sub[1], discard);
+ default: assert(!"nyi expr");
+ }
+}
+
+/************************************/
+/* Statements parsing & compilation */
+/************************************/
+
+static void
+stmtterm(struct comp *cm)
+{
+ expect(cm, ';', "to terminate previous statement");
+}
+
+static void block(struct comp *cm, struct function *fn);
+static bool stmt(struct comp *cm, struct function *fn);
+static void localdecl(struct comp *cm, struct function *fn, bool forinit);
+
+struct label {
+ struct label *link;
+ internstr name;
+ struct block *blk;
+ struct span usespan;
+ /* if usespan.ex.len == 0, this label is resolved and blk is the block that
+ * the label starts, otherwise the label is unresolved and blk is the head
+ * of a linked list of relocations, the next list entry is in blk->s1, etc,
+ * terminated by NULL */
+};
+
+static struct label *
+findlabel(struct comp *cm, internstr name)
+{
+ for (struct label *l = cm->labels; l; l = l->link)
+ if (l->name == name) return l;
+ return NULL;
+}
+
+static void
+deflabel(struct comp *cm, struct function *fn, const struct span *span, internstr name)
+{
+ struct label *label = findlabel(cm, name);
+ if (label && label->usespan.ex.len == 0) {
+ error(span, "redefinition of label '%s'", name);
+ } else if (label) {
+ struct block *new = NULL;
+ if (!nerror) {
+ new = newblk(fn);
+ if (fn->curblk) putbranch(fn, new);
+ }
+ /* fix up relocations */
+ for (struct block *list = label->blk, *next; list; list = next) {
+ next = list->s1;
+ if (!nerror) {
+ useblk(fn, list);
+ putbranch(fn, new);
+ }
+ }
+ label->usespan = (struct span){0};
+ label->blk = new;
+ if (!nerror) useblk(fn, new);
+ } else {
+ struct label l = { cm->labels, name };
+ if (!nerror) {
+ struct block *new = newblk(fn);
+ if (fn->curblk) putbranch(fn, new);
+ useblk(fn, new);
+ }
+ l.blk = fn->curblk;
+ cm->labels = alloccopy(fn->arena, &l, sizeof l, 0);
+ }
+}
+
+static bool
+loopbody(struct comp *cm, struct function *fn, struct block *brk, struct block *cont)
+{
+ struct block *save[2];
+ bool terminates = 0;
+
+ save[0] = cm->breakto, save[1] = cm->loopcont;
+ cm->breakto = brk, cm->loopcont = cont;
+ ++cm->loopdepth;
+
+ terminates = stmt(cm, fn);
+
+ --cm->loopdepth;
+ cm->breakto = save[0], cm->loopcont = save[1];
+
+ return terminates;
+}
+
+#define EMITS if (doemit && !nerror)
+
+struct swcase {
+ vlong val;
+ struct block *blk;
+ struct span span;
+};
+struct switchstmt {
+ struct block *bdefault;
+ union type condtype;
+ vec_of(struct swcase) cases;
+};
+
+static int
+cmpswcase(const void *aa, const void *bb)
+{
+ const struct swcase *a = aa, *b = bb;
+ vlong v1 = a->val, v2 = b->val;
+ if (v1 != v2) return v1 < v2 ? -1 : 1;
+ return (a > b) - (a < b); /* preserve original order */
+}
+
+static void
+swsortcases(struct swcase *cs, uint n)
+{
+ void qsort(void *, size_t n, size_t size, int (*)(const void *, const void *));
+ qsort(cs, n, sizeof *cs, cmpswcase);
+}
+
+static bool
+genswitch(struct comp *cm, struct function *fn, const struct expr *ex)
+{
+ union ref sel;
+ bool doemit = fn->curblk;
+ struct block *begin = NULL, *end = NULL, *breaksave = cm->breakto;
+ struct switchstmt *stsave = cm->switchstmt, st = {.condtype = ex->ty};
+ enum irclass k = type2cls[scalartypet(ex->ty)];
+ struct swcase casebuf[8];
+ vinit(&st.cases, casebuf, countof(casebuf));
+
+ assert(k);
+ end = newblk(fn);
+ EMITS {
+ sel = exprvalue(fn, ex);
+ assert(isint(ex->ty));
+ }
+ cm->switchstmt = &st;
+ cm->breakto = end;
+ begin = fn->curblk;
+ fn->curblk = NULL;
+ ++cm->switchdepth;
+ stmt(cm, fn);
+ --cm->switchdepth;
+ doemit = fn->curblk;
+ cm->switchstmt = stsave;
+ cm->breakto = breaksave;
+
+ EMITS putbranch(fn, end);
+ useblk(fn, begin);
+ swsortcases(st.cases.p, st.cases.n);
+ doemit = 1;
+ if (!st.bdefault) st.bdefault = end;
+ /* TODO: optimize instead of generating the equivalent of if == .. else if .. chain
+ * XX 1. sort by case values (also for easy duplicates checking)
+ * 2. contiguous ranges (case a..b: -> x >= && x <= b)
+ * 3. binary search
+ * 4. jump tables? (harder, backend refactoring)
+ */
+ vlong prev;
+ for (int i = 0; i < st.cases.n; ++i) {
+ const struct swcase *c = &st.cases.p[i];
+ if (i > 0) {
+ assert(c->val >= prev);
+ if (c->val == prev) {
+ error(&c->span, "duplicate case value");
+ note(&c[-1].span, "previously defined here");
+ }
+ }
+ EMITS {
+ struct block *next = i < st.cases.n - 1 ? newblk(fn) : st.bdefault;
+ putcondbranch(fn, irbinop(fn, Oequ, k, sel, mkintcon(k, c->val)), c->blk, next);
+ if (next != st.bdefault) useblk(fn, next);
+ }
+ prev = c->val;
+ }
+ vfree(&st.cases);
+ if (fn->curblk != end) {
+ if (fn->curblk) EMITS putbranch(fn, end);
+ if (end->npred > 0) {
+ useblk(fn, end);
+ } else {
+ fn->curblk = NULL;
+ freeblk(fn, end);
+ }
+ }
+
+ return fn->curblk == NULL;
+}
+
+static bool /* return 1 if stmt is terminating (ends with a jump) */
+stmt(struct comp *cm, struct function *fn)
+{
+ struct block *tr, *fl, *end, *begin;
+ union {
+ struct arena a;
+ char mem[sizeof(struct arena) + sizeof(struct expr)*4];
+ } atmp = { .a.cap = sizeof(struct expr)*4 };
+ struct arena *atmpp;
+ struct expr ex;
+ struct env e;
+ union ref r;
+ struct token tk;
+ bool terminates = 0;
+ bool doemit = fn->curblk;
+
+ while (match(cm, &tk, TKIDENT) || match(cm, &tk, TKWcase) || match(cm, &tk, TKWdefault)) {
+ if (tk.t == TKWcase) {
+ /* case <expr> ':' */
+ if (!cm->switchstmt) error(&tk.span, "'case' outside of switch statement");
+ ex = constantexpr(cm);
+ if (!eval(&ex, EVINTCONST))
+ error(&ex.span, "not an integer constant expression");
+ else if (cm->switchstmt && ex.ty.bits != cm->switchstmt->condtype.bits) {
+ struct expr tmp = ex;
+ ex = mkexpr(ECAST, ex.span, cm->switchstmt->condtype, .sub = &tmp);
+ bool ok = eval(&ex, EVINTCONST);
+ assert(ok && "cast const int?");
+ if (ex.i != tmp.i)
+ warn(&ex.span, "overflow converting case value to switch condition type");
+ }
+ expect(cm, ':', NULL);
+ if (!fn->curblk || (fn->curblk->phi.n > 0 || fn->curblk->ins.n > 0)) {
+ begin = newblk(fn);
+ EMITS putbranch(fn, begin);
+ useblk(fn, begin);
+ }
+ if (cm->switchstmt)
+ vpush(&cm->switchstmt->cases, ((struct swcase) {ex.i, fn->curblk, ex.span}));
+ } else if (tk.t == TKWdefault) {
+ /* default ':' */
+ if (!cm->switchstmt) error(&tk.span, "'default' outside of switch statement");
+ expect(cm, ':', NULL);
+ if (!fn->curblk || (fn->curblk->phi.n > 0 || fn->curblk->ins.n > 0)) {
+ begin = newblk(fn);
+ EMITS putbranch(fn, begin);
+ useblk(fn, begin);
+ }
+ if (cm->switchstmt) {
+ if (cm->switchstmt->bdefault) error(&tk.span, "multiple 'default' labels in one switch");
+ cm->switchstmt->bdefault = fn->curblk;
+ }
+ } else if (tk.t == TKIDENT && match(cm, NULL, ':')) {
+ /* <label> ':' */
+ deflabel(cm, fn, &tk.span, tk.name);
+ } else {
+ assert(tk.t == TKIDENT);
+ /* kludge for no backtracking and no lookahead */
+ ex = exprparse(cm, 1, &tk, EFROMSTMT);
+ stmtterm(cm);
+ EMITS expreffects(fn, &ex);
+ return fn->curblk == NULL;
+ }
+ doemit = 1;
+ }
+
+ switch (peek(cm, NULL)) {
+ case '{':
+ lex(cm, NULL);
+ envdown(cm, &e);
+ block(cm, fn);
+ envup(cm);
+ break;
+ case ';':
+ lex(cm, NULL);
+ break;
+ case TKWif:
+ lex(cm, NULL);
+ expect(cm, '(', NULL);
+ ex = commaexpr(cm);
+ expect(cm, ')', NULL);
+ if (!isscalar(ex.ty))
+ error(&ex.span, "'if' condition is not a scalar '%ty'", ex.ty);
+ tr = fl = end = NULL;
+ EMITS {
+ tr = newblk(fn);
+ fl = newblk(fn);
+ condjump(fn, &ex, tr, fl);
+ useblk(fn, tr);
+ }
+ terminates = stmt(cm, fn);
+ if (!match(cm, NULL, TKWelse)) {
+ end = fl;
+ EMITS if (!terminates) putbranch(fn, end);
+ terminates = 0;
+ } else {
+ EMITS {
+ end = newblk(fn);
+ if (!terminates) putbranch(fn, end);
+ useblk(fn, fl);
+ }
+ terminates &= stmt(cm, fn);
+ EMITS {
+ if (fn->curblk) putbranch(fn, end);
+ }
+ }
+ EMITS if (!terminates) useblk(fn, end);
+ break;
+ case TKWelse:
+ lex(cm, &tk);
+ error(&tk.span, "'else' without matching 'if'");
+ break;
+ case TKWwhile: /* while ( <cond> ) <body> */
+ lex(cm, NULL);
+ expect(cm, '(', NULL);
+ ex = commaexpr(cm);
+ expect(cm, ')', NULL);
+ if (!isscalar(ex.ty))
+ error(&ex.span, "'while' condition is not a scalar '%ty'", ex.ty);
+ tr = begin = end = NULL;
+ /* @begin:
+ * <cond>
+ * b <cond>, @tr, @end
+ * @tr:
+ * <body>
+ * b @begin
+ * @end:
+ * <-
+ */
+ doemit = 1;
+ EMITS {
+ begin = newblk(fn);
+ if (fn->curblk)
+ putbranch(fn, begin);
+ useblk(fn, begin);
+ condjump(fn, &ex, tr = newblk(fn), end = newblk(fn));
+ useblk(fn, tr);
+ }
+ terminates = loopbody(cm, fn, end, begin);
+ EMITS {
+ if (fn->curblk) putbranch(fn, begin);
+ useblk(fn, end);
+ }
+ break;
+ case TKWdo: /* do <body> while ( <cond> ) ; */
+ lex(cm, NULL);
+ begin = tr = end = NULL;
+ /* @begin:
+ * <body>
+ * b @tr
+ * @tr: <- necessary for continue stmt
+ * <cond>
+ * b <cond>, @begin, @end
+ * @end:
+ * <-
+ */
+ doemit = 1;
+ EMITS {
+ begin = newblk(fn);
+ if (fn->curblk)
+ putbranch(fn, begin);
+ useblk(fn, begin);
+ tr = newblk(fn);
+ end = newblk(fn);
+ }
+ terminates = loopbody(cm, fn, end, tr);
+ expect(cm, TKWwhile, NULL);
+ expect(cm, '(', NULL);
+ ex = commaexpr(cm);
+ expect(cm, ')', NULL);
+ if (!isscalar(ex.ty))
+ error(&ex.span, "'while' condition is not a scalar '%ty'", ex.ty);
+ stmtterm(cm);
+ EMITS {
+ if (!terminates) putbranch(fn, tr);
+ useblk(fn, tr);
+ condjump(fn, &ex, begin, end);
+ useblk(fn, end);
+ }
+ break;
+ case TKWfor: /* for ( <init>? ; <cond>? ; <iter>? ) <body> */
+ lex(cm, NULL);
+ begin = tr = end = fl = NULL;
+ expect(cm, '(', NULL);
+ /* ->
+ * <init>
+ * b @begin
+ * @begin:
+ * <cond>
+ * b <cond>, @tr, @fl
+ * @tr:
+ * <body>
+ * b @end
+ * @end: <- necessary for continue stmt
+ * <iter>
+ * b @begin
+ * @fl:
+ * <-
+ *
+ * if cond omitted, tr = begin
+ * if iter omitted, end = begin
+ */
+ envdown(cm, &e);
+ if (!match(cm, NULL, ';')) { /* init */
+ if (isdecltok(cm)) {
+ localdecl(cm, fn, 1);
+ } else {
+ ex = commaexpr(cm);
+ EMITS expreffects(fn, &ex);
+ expect(cm, ';', NULL);
+ }
+ }
+ doemit = 1;
+ EMITS {
+ end = tr = begin = newblk(fn);
+ if (fn->curblk)
+ putbranch(fn, begin);
+ useblk(fn, begin);
+ fl = newblk(fn);
+ }
+ if (!match(cm, NULL, ';')) { /* cond */
+ ex = commaexpr(cm);
+ expect(cm, ';', NULL);
+ if (!isscalar(ex.ty))
+ error(&ex.span, "'for' condition is not a scalar type ('%ty')", ex.ty);
+ EMITS {
+ tr = newblk(fn);
+ condjump(fn, &ex, tr, fl);
+ useblk(fn, tr);
+ }
+ }
+ atmpp = NULL;
+ if (!match(cm, NULL, ')')) { /* iter */
+ /* since exarena is free'd at the end of each stmt, create a new temporary
+ * arena to parse this expression because loop body statements would free it
+ * otherwise */
+ struct arena *tmp = cm->exarena;
+ cm->exarena = &atmp.a;
+ ex = commaexpr(cm);
+ atmpp = cm->exarena;
+ cm->exarena = tmp;
+
+ end = newblk(fn);
+ expect(cm, ')', NULL);
+ }
+
+ terminates = loopbody(cm, fn, fl, end);
+
+ EMITS {
+ if (end != begin) { /* have iter */
+ if (!terminates) putbranch(fn, end);
+ useblk(fn, end);
+ expreffects(fn, &ex);
+ putbranch(fn, begin);
+ } else if (!terminates) putbranch(fn, begin);
+ if (fl->npred > 0) {
+ useblk(fn, fl);
+ } else {
+ freeblk(fn, fl);
+ terminates = 1;
+ }
+ }
+ if (atmpp && atmpp != cm->exarena) freearena(&atmpp);
+ envup(cm);
+ break;
+ case TKWswitch:
+ lex(cm, NULL);
+ expect(cm, '(', NULL);
+ ex = commaexpr(cm);
+ expect(cm, ')', NULL);
+ if (!isint(ex.ty))
+ error(&ex.span, "'switch' value is not an integer: '%ty'", ex.ty);
+ terminates = genswitch(cm, fn, &ex);
+ break;
+ case TKWbreak:
+ lex(cm, &tk);
+ if (!cm->loopdepth && !cm->switchdepth)
+ error(&tk.span, "'break' outside of loop or switch statement");
+ EMITS putbranch(fn, cm->breakto);
+ stmtterm(cm);
+ break;
+ case TKWcontinue:
+ lex(cm, &tk);
+ if (!cm->loopdepth)
+ error(&tk.span, "'continue' outside of loop");
+ EMITS putbranch(fn, cm->loopcont);
+ stmtterm(cm);
+ break;
+ case TKWgoto:
+ lex(cm, &tk);
+ peek(cm, &tk);
+ if (expect(cm, TKIDENT, NULL)) {
+ struct label *label = findlabel(cm, tk.name);
+ if (!label) {
+ /* create reloc list */
+ struct label l = { cm->labels, tk.name, fn->curblk, tk.span };
+ assert(l.usespan.ex.len);
+ cm->labels = alloccopy(fn->arena, &l, sizeof l, 0);
+ fn->curblk = NULL;
+ } else if (label && label->usespan.ex.len != 0) {
+ /* append to relocs list */
+ struct block *next = label->blk;
+ label->blk = fn->curblk;
+ EMITS {
+ fn->curblk->s1 = next;
+ fn->curblk = NULL;
+ }
+ } else {
+ EMITS {
+ assert(label->blk);
+ putbranch(fn, label->blk);
+ }
+ }
+ }
+ stmtterm(cm);
+ break;
+ case TKWreturn:
+ lex(cm, &tk);
+ if (isexprtok(cm)) {
+ ex = commaexpr(cm);
+ if (fn->retty.t == TYVOID) {
+ if (ex.ty.t != TYVOID) error(&ex.span, "void function should not return a value");
+ else if (ccopt.pedant) warn(&ex.span, "returning void expression is an extension");
+ } else if (!assigncheck(fn->retty, &ex)) {
+ error(&ex.span,
+ "cannot return '%ty' value from function with return type '%ty'",
+ ex.ty, fn->retty);
+ }
+ EMITS {
+ if (isscalar(fn->retty))
+ r = scalarcvt(fn, fn->retty, ex.ty, exprvalue(fn, &ex));
+ else if (fn->retty.t == TYVOID)
+ r = (expreffects(fn, &ex), NOREF);
+ else
+ r = structreturn(fn, &ex);
+ putreturn(fn, r, NOREF);
+ }
+ } else {
+ if (fn->retty.t != TYVOID)
+ error(&tk.span, "non-void function should return a value");
+ EMITS putreturn(fn, NOREF, NOREF);
+ }
+ stmtterm(cm);
+ break;
+ default:
+ ex = exprparse(cm, 1, NULL, EFROMSTMT);
+ stmtterm(cm);
+ EMITS expreffects(fn, &ex);
+ break;
+ }
+ freearena(&cm->exarena);
+ lexerfreetemps(cm->lx);
+ return fn->curblk == NULL;
+}
+
+/* parse and compile a function-local declaration */
+static void
+localdecl(struct comp *cm, struct function *fn, bool forini)
+{
+ struct expr ini;
+ struct token tk;
+ const bool doemit = fn->curblk;
+ struct declstate st = { DFUNCVAR };
+
+ if (!forini && match(cm, &tk, TKIDENT)) {
+ if (match(cm, NULL, ':')) {
+ /* <label> ':' */
+ deflabel(cm, fn, &tk.span, tk.name);
+ stmt(cm, fn);
+ return;
+ }
+ /* finddecl() -> non null because localdecl() is called when isdecltok() */
+ st.base = finddecl(cm, tk.name)->ty;
+ st.base0 = 1;
+ }
+ do {
+ struct decl decl = pdecl(&st, cm);
+ if (decl.name) {
+ static int staticid;
+ bool put = 0;
+ bool dynarr = 0;
+
+ switch (decl.scls) {
+ case SCSTATIC:
+ if (forini)
+ error(&decl.span, "static declaration in 'for' loop initializer");
+ if (!decl.sym)
+ decl.sym = mkhiddensym(&fn->name->c, &decl.name->c, ++staticid);
+ goto Initz;
+ case SCNONE:
+ if (decl.ty.t == TYFUNC) {
+ decl.scls = SCEXTERN;
+ if (!decl.sym) decl.sym = decl.name;
+ break;
+ }
+ decl.scls = SCAUTO;
+ /* fallthru */
+ case SCAUTO:
+ case SCREGISTER:
+ if (decl.ty.t == TYFUNC) {
+ error(&decl.span, "declaring variable '%s' with function type '%ty'", decl.name, decl.ty);
+ goto Err;
+ } else if (isincomplete(decl.ty) && !(dynarr = (decl.ty.t == TYARRAY && st.varini))) {
+ error(&decl.span, "declaring variable '%s' with incomplete type '%ty'", decl.name, decl.ty);
+ goto Err;
+ }
+ decl.id = -1;
+ if (!nerror) {
+ struct instr alloc = mkalloca(typesize(decl.ty), typealign(decl.ty));
+ if (fn->curblk) decl.id = addinstr(fn, alloc).i;
+ else decl.id = insertinstr(fn->entry, fn->entry->ins.n, alloc).i;
+ }
+ Initz:
+ if (st.varini) {
+ int d = putdecl(cm, &decl);
+ union type ty = decl.ty;
+ bool statik = decl.scls & (SCSTATIC | SCEXTERN);
+ ini = initializer(cm, &ty, statik ? EVSTATICINI : EVFOLD,
+ /* globl? */ decl.scls == SCEXTERN, decl.qual, statik ? decl.sym : NULL);
+ declsbuf.p[d].ty = ty;
+ put = 1;
+ pdecl(&st, cm);
+ if (!statik) {
+ /* fix alloca for actual size, for implicitly sized arrays */
+ assert(!isincomplete(ty));
+ EMITS instrtab[decl.id] = mkalloca(typesize(ty), typealign(ty));
+
+ if (!initcheck(ty, &ini)) {
+ struct span span = decl.span;
+ joinspan(&span.ex, ini.span.ex);
+ error(&span, "cannot initialize '%ty' variable with '%ty'",
+ ty, ini.ty);
+ }
+ EMITS {
+ if (ini.t == EINIT || (ty.t == TYARRAY && ini.t == ESTRLIT))
+ geninit(fn, ty, mkref(RTMP, decl.id), &ini);
+ else if (isagg(ty))
+ structcopy(fn, ty, mkref(RTMP, decl.id), exprvalue(fn, &ini));
+ else {
+ genstore(fn, ty, mkref(RTMP, decl.id),
+ scalarcvt(fn, ty, ini.ty, exprvalue(fn, &ini)));
+ }
+ }
+ } else if (decl.scls == SCEXTERN) {
+ struct span span = decl.span;
+ joinspan(&span.ex, ini.span.ex);
+ error(&span, "block local 'extern' variable cannot have an initializer");
+ }
+ } else if (decl.scls == SCSTATIC) {
+ /* zero-initialized static */
+ if (decl.ty.t == TYARRAY && isincomplete(decl.ty))
+ error(&decl.span, "definition of variable with array type needs size or initializer");
+ else if (isincomplete(decl.ty))
+ error(&decl.span, "definition of static variable with incomplete type");
+ else
+ objnewdat(decl.sym, Sbss, 0, typesize(decl.ty), typealign(decl.ty));
+ }
+ break;
+ case SCTYPEDEF:
+ if (forini)
+ error(&decl.span, "typedef in 'for' loop initializer");
+ break;
+ case SCEXTERN:
+ if (!decl.sym) decl.sym = decl.name;
+ if (forini)
+ error(&decl.span, "extern declaration in 'for' loop initializer");
+ if (st.varini) goto Initz;
+ break;
+ default: assert(0);
+ }
+ if (st.funcdef) {
+ struct span span = decl.span;
+ joinspan(&span.ex, (peek(cm, &tk), tk.span.ex));
+ error(&span, "function definition not allowed here");
+ int bal = 1;
+ do switch (lex(cm, NULL)) {
+ case TKEOF: break;
+ case '{': ++bal; break;
+ case '}': --bal; break;
+ } while (bal);
+ }
+ Err:
+ if (!put) putdecl(cm, &decl);
+ } else if (forini) {
+ error(&decl.span, "non-variable declaration in 'for' loop initializer");
+ }
+ } while (st.more);
+}
+
+static void
+block(struct comp *cm, struct function *fn)
+{
+ struct token tk;
+
+ while (!match(cm, &tk, '}')) {
+ if (isdecltok(cm))
+ localdecl(cm, fn, 0);
+ else
+ stmt(cm, fn);
+ }
+ cm->fnblkspan = tk.span;
+}
+
+static void
+function(struct comp *cm, struct function *fn, internstr *pnames, const struct span *pspans, uchar *pquals)
+{
+ const struct typedata *td = &typedata[fn->fnty.dat];
+ const bool doemit = fn->curblk;
+ struct env e;
+ struct token tk;
+ envdown(cm, &e);
+
+ /* emit Oparam instructions */
+ EMITS {
+ for (int i = 0; i < td->nmemb; ++i) {
+ union irtype pty = mkirtype(td->param[i]);
+ union ref r = addinstr(fn, mkinstr(Oparam, pty.isagg ? KPTR : pty.cls,
+ mkref(RICON, i), mktyperef(pty)));
+ assert(r.t == RTMP && r.i == i);
+ }
+ }
+ /* add parameters to symbol table and create prologue (arguments) block */
+ for (int i = 0; i < td->nmemb; ++i) {
+ if (pnames[i]) {
+ struct decl arg = { .ty = td->param[i], .qual = pquals ? pquals[i] : 0,
+ .name = pnames[i], .scls = SCAUTO, .span = pspans[i] };
+ EMITS {
+ if (isscalar(arg.ty)) {
+ arg.id = addinstr(fn, mkalloca(typesize(arg.ty), typealign(arg.ty))).i;
+ genstore(fn, arg.ty, mkref(RTMP, arg.id), mkref(RTMP, i));
+ } else {
+ arg.id = addinstr(fn, mkinstr(Ocopy, KPTR, mkref(RTMP, i))).i;
+ }
+ }
+ putdecl(cm, &arg);
+ } else if (ccopt.cstd < STDC23) {
+ warn(&pspans[i], "missing name of parameter #%d", i+1);
+ }
+ }
+
+ /* put __func__, though its data is generated lazily the first time it is encountered */
+ putdecl(cm, &(struct decl) {
+ .ty = mkarrtype(mktype(TYCHAR), QCONST, strlen(&fn->name->c) + 1), .qual = QCONST,
+ .name = istr__func__, .scls = SCSTATIC, .span = (peek(cm, &tk), tk.span),
+ .isbuiltin = 1, .sym = fn->name,
+ });
+
+ /* end prologue */
+ EMITS {
+ struct block *blk;
+ putbranch(fn, blk = newblk(fn));
+ useblk(fn, blk);
+ }
+ cm->labels = NULL;
+ block(cm, fn);
+ envup(cm);
+ for (struct label *l = cm->labels; l; l = l->link) {
+ if (l->usespan.ex.len) {
+ error(&l->usespan, "label '%s' used but never defined", l->name);
+ }
+ }
+ if (fn->curblk) {
+ if (fn->retty.t == TYINT && fn->name == istr_main) {
+ /* implicit return 0 for main function (ISO C standard behavior) */
+ putreturn(fn, ZEROREF, NOREF);
+ } else {
+ if (fn->retty.t != TYVOID && !nerror) {
+ /* it may not actually be reachable after constant-folding
+ * peephole optimizations (from code like assert(0 && "x")) */
+ if (blkreachable(fn, fn->curblk)) {
+ warn(&cm->fnblkspan, "non-void function '%s' may not return a value", fn->name);
+ }
+ }
+ putreturn(fn, NOREF, NOREF);
+ }
+ }
+}
+
+/* top-level declaration */
+static void
+tldecl(struct comp *cm)
+{
+ struct declstate st = { DTOPLEVEL };
+ do {
+ bool noscls = 0;
+ int nerr = nerror;
+ struct decl decl = pdecl(&st, cm);
+
+ if (nerror != nerr && st.varini) {
+ (void)expr(cm);
+ pdecl(&st, cm);
+ continue;
+ }
+ if (st.empty) break;
+ if (!decl.scls) {
+ noscls = 1;
+ decl.scls = SCEXTERN;
+ }
+ if (!decl.sym) decl.sym = decl.name;
+ decl.isdef = st.varini;
+ if (st.funcdef) {
+ const struct typedata *td = &typedata[decl.ty.dat];
+ if (td->ret.t != TYVOID && isincomplete(td->ret))
+ error(&decl.span, "function definition with incomplete return type '%ty'", td->ret);
+ for (int i = 0; i < td->nmemb; ++i) {
+ if (td->param[i].t != TYVOID && isincomplete(td->param[i]))
+ error(&st.pspans[i], "parameter has incomplete type '%ty'", td->param[i]);
+ }
+ decl.isdef = 1;
+ int idecl = putdecl(cm, &decl);
+ struct decl *d = &declsbuf.p[idecl];
+ if (d->inlin && decl.scls != SCSTATIC) fatal(&d->span, "non-static inline is unimplemented");
+ struct function fn = { &cm->fnarena, .name = d->sym, .globl = d->scls != SCSTATIC, .fnty = decl.ty, .retty = td->ret, .inlin = d->inlin };
+ irinit(&fn);
+ function(cm, &fn, st.pnames, st.pspans, st.pqual);
+ if (!nerror && ccopt.dbg.p)
+ irdump(&fn);
+ irfini(&fn);
+ } else if (decl.name) {
+ int idecl = putdecl(cm, &decl);
+ struct decl *d = &declsbuf.p[idecl];
+ if (st.varini) {
+ if (isagg(decl.ty) && isincomplete(decl.ty))
+ error(&decl.span, "initialization of variable with incomplete type '%ty'", decl.ty);
+ struct expr ini = initializer(cm, &decl.ty, EVSTATICINI, d->scls != SCSTATIC, d->qual, d->sym);
+ d = &declsbuf.p[idecl];
+ d->ty = decl.ty;
+ if (d->scls == SCEXTERN && !noscls) {
+ struct span span = decl.span;
+ joinspan(&span.ex, ini.span.ex);
+ warn(&span, "'extern' variable has initializer");
+ }
+ pdecl(&st, cm);
+ } else if (d->ty.t != TYFUNC && d->scls != SCTYPEDEF && (d->scls != SCEXTERN || noscls)) {
+ /* tentative definitions */
+ if (!objhassym(d->sym, NULL)) {
+ uint size = typesize(d->ty);
+ if (isincomplete(d->ty)) {
+ if (d->ty.t == TYARRAY) {
+ warn(&d->span, "tentative array definition assumed to have one element");
+ size = typesize(typechild(d->ty));
+ assert(size != 0);
+ } else if (isagg(d->ty)) {
+ warn(&d->span, "tentative definition with incomplete type '%ty'", d->ty);
+ assert(size == 0);
+ } else assert(0);
+ }
+ if (size) objnewdat(d->sym, Sbss, d->scls == SCEXTERN, size, typealign(d->ty));
+ }
+ }
+ if (ccopt.dbg.p) bfmt(ccopt.dbgout, "var %s : %tq\n", d->name, d->ty, d->qual);
+ } else {
+ if (ccopt.dbg.p && decl.ty.t) bfmt(ccopt.dbgout, "type %ty\n", decl.ty);
+ }
+ freearena(&cm->fnarena);
+ freearena(&cm->exarena);
+ lexerfreetemps(cm->lx);
+ } while (st.more);
+}
+
+union type cvalistty;
+void
+docomp(struct comp *cm)
+{
+ static struct env toplevel;
+ struct token tk[1];
+
+ istr__func__ = intern("__func__");
+ istr_main = intern("main");
+ istr_memset = intern("memset");
+ if (!cm->env) {
+ vinit(&declsbuf, NULL, 1<<10);
+ pmap_init(&tldeclmap, 1<<8);
+ cm->env = &toplevel;
+ }
+ if (!cvalistty.t) {
+ struct typedata td = {
+ .t = TYSTRUCT, .siz = targ_valistsize, .align = targ_primalign[TYPTR], .nmemb = 1,
+ .fld = &(struct namedfield){intern("-"), {mkarrtype(mktype(TYPTR), 0, 3)}}
+ };
+ cvalistty = mkarrtype(mktagtype(intern("__builtin_va_list"), &td), 0, 1);
+ }
+ peek(cm, tk);
+ envadddecl(cm->env, &(struct decl) { cvalistty, SCTYPEDEF, .span = tk->span, .name = intern("__builtin_va_list") });
+ putbuiltins(cm->env);
+
+ while (peek(cm, tk) != TKEOF) {
+ if (tk->t == ';') {
+ lex(cm, tk);
+ } else if (!isdecltok(cm) && tk->t != TKIDENT) {
+ error(&tk->span, "expected declaration");
+ do lex(cm, tk); while (tk->t != TKEOF && !isdecltok(cm));
+ } else {
+ tldecl(cm);
+ }
+ }
+}
+
+static void
+initcm(struct comp *cm, const char *file)
+{
+ enum { N = 1<<12 };
+ static union { char m[sizeof(struct arena) + N]; struct arena *_align; } amem[2];
+ const char *err;
+ switch (initlexer(cm->lx, &err, file)) {
+ default: assert(0);
+ case LXERR:
+ fatal(NULL, "Cannot open %'s: %s", file, err);
+ case LXOK:
+ cm->fnarena = (void *)amem[0].m;
+ cm->fnarena->cap = N;
+ cm->exarena = (void *)amem[1].m;
+ cm->exarena->cap = N;
+ }
+}
+
+void
+ccomp(const char *file)
+{
+ struct comp cm = {&(struct lexer){0}};
+ initcm(&cm, file);
+ docomp(&cm);
+}
+
+void
+cpp(struct wbuf *out, const char *file)
+{
+ struct comp cm = {&(struct lexer){0}};
+ initcm(&cm, file);
+ lexerdump(cm.lx, out);
+}
+
+/* vim:set ts=3 sw=3 expandtab: */
generated by cgit v1.2.3 (git 2.39.1) at 2026-05-01 21:09:43 +0000