Alien-TinyCC

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src/tccgen.c  view on Meta::CPAN

    vtop++;
    *vtop = *v;
}

static void vdup(void)
{
    vpushv(vtop);
}

/* save r to the memory stack, and mark it as being free */
ST_FUNC void save_reg(int r)
{
    int l, saved, size, align;
    SValue *p, sv;
    CType *type;

    /* modify all stack values */
    saved = 0;
    l = 0;
    for(p=vstack;p<=vtop;p++) {
        if ((p->r & VT_VALMASK) == r ||
            ((p->type.t & VT_BTYPE) == VT_LLONG && (p->r2 & VT_VALMASK) == r)) {
            /* must save value on stack if not already done */
            if (!saved) {
                /* NOTE: must reload 'r' because r might be equal to r2 */
                r = p->r & VT_VALMASK;
                /* store register in the stack */
                type = &p->type;
                if ((p->r & VT_LVAL) ||
                    (!is_float(type->t) && (type->t & VT_BTYPE) != VT_LLONG))
#ifdef TCC_TARGET_X86_64
                    type = &char_pointer_type;
#else
                    type = &int_type;
#endif
                size = type_size(type, &align);
                loc = (loc - size) & -align;
                sv.type.t = type->t;
                sv.r = VT_LOCAL | VT_LVAL;
                sv.c.ul = loc;
                store(r, &sv);
#if defined(TCC_TARGET_I386) || defined(TCC_TARGET_X86_64)
                /* x86 specific: need to pop fp register ST0 if saved */
                if (r == TREG_ST0) {
                    o(0xd8dd); /* fstp %st(0) */
                }
#endif
#ifndef TCC_TARGET_X86_64
                /* special long long case */
                if ((type->t & VT_BTYPE) == VT_LLONG) {
                    sv.c.ul += 4;
                    store(p->r2, &sv);
                }
#endif
                l = loc;
                saved = 1;
            }
            /* mark that stack entry as being saved on the stack */
            if (p->r & VT_LVAL) {
                /* also clear the bounded flag because the
                   relocation address of the function was stored in
                   p->c.ul */
                p->r = (p->r & ~(VT_VALMASK | VT_BOUNDED)) | VT_LLOCAL;
            } else {
                p->r = lvalue_type(p->type.t) | VT_LOCAL;
            }
            p->r2 = VT_CONST;
            p->c.ul = l;
        }
    }
}

#ifdef TCC_TARGET_ARM
/* find a register of class 'rc2' with at most one reference on stack.
 * If none, call get_reg(rc) */
ST_FUNC int get_reg_ex(int rc, int rc2)
{
    int r;
    SValue *p;
    
    for(r=0;r<NB_REGS;r++) {
        if (reg_classes[r] & rc2) {
            int n;
            n=0;
            for(p = vstack; p <= vtop; p++) {
                if ((p->r & VT_VALMASK) == r ||
                    (p->r2 & VT_VALMASK) == r)
                    n++;
            }
            if (n <= 1)
                return r;
        }
    }
    return get_reg(rc);
}
#endif

/* find a free register of class 'rc'. If none, save one register */
ST_FUNC int get_reg(int rc)
{
    int r;
    SValue *p;

    /* find a free register */
    for(r=0;r<NB_REGS;r++) {
        if (reg_classes[r] & rc) {
            for(p=vstack;p<=vtop;p++) {
                if ((p->r & VT_VALMASK) == r ||
                    (p->r2 & VT_VALMASK) == r)
                    goto notfound;
            }
            return r;
        }
    notfound: ;
    }
    
    /* no register left : free the first one on the stack (VERY
       IMPORTANT to start from the bottom to ensure that we don't
       spill registers used in gen_opi()) */
    for(p=vstack;p<=vtop;p++) {
        /* look at second register (if long long) */

src/tccgen.c  view on Meta::CPAN

    }
    decl_initializer(type, sec, c, 0, size_only);

    /* XXX: make it more general */
    if (!size_only && nb_elems > 1) {
        unsigned long c_end;
        uint8_t *src, *dst;
        int i;

        if (!sec)
            tcc_error("range init not supported yet for dynamic storage");
        c_end = c + nb_elems * elem_size;
        if (c_end > sec->data_allocated)
            section_realloc(sec, c_end);
        src = sec->data + c;
        dst = src;
        for(i = 1; i < nb_elems; i++) {
            dst += elem_size;
            memcpy(dst, src, elem_size);
        }
    }
}

#define EXPR_VAL   0
#define EXPR_CONST 1
#define EXPR_ANY   2

/* store a value or an expression directly in global data or in local array */
static void init_putv(CType *type, Section *sec, unsigned long c, 
                      int v, int expr_type)
{
    int saved_global_expr, bt, bit_pos, bit_size;
    void *ptr;
    unsigned long long bit_mask;
    CType dtype;

    switch(expr_type) {
    case EXPR_VAL:
        vpushi(v);
        break;
    case EXPR_CONST:
        /* compound literals must be allocated globally in this case */
        saved_global_expr = global_expr;
        global_expr = 1;
        expr_const1();
        global_expr = saved_global_expr;
        /* NOTE: symbols are accepted */
        if ((vtop->r & (VT_VALMASK | VT_LVAL)) != VT_CONST)
            tcc_error("initializer element is not constant");
        break;
    case EXPR_ANY:
        expr_eq();
        break;
    }
    
    dtype = *type;
    dtype.t &= ~VT_CONSTANT; /* need to do that to avoid false warning */

    if (sec) {
        /* XXX: not portable */
        /* XXX: generate error if incorrect relocation */
        gen_assign_cast(&dtype);
        bt = type->t & VT_BTYPE;
        /* we'll write at most 12 bytes */
        if (c + 12 > sec->data_allocated) {
            section_realloc(sec, c + 12);
        }
        ptr = sec->data + c;
        /* XXX: make code faster ? */
        if (!(type->t & VT_BITFIELD)) {
            bit_pos = 0;
            bit_size = 32;
            bit_mask = -1LL;
        } else {
            bit_pos = (vtop->type.t >> VT_STRUCT_SHIFT) & 0x3f;
            bit_size = (vtop->type.t >> (VT_STRUCT_SHIFT + 6)) & 0x3f;
            bit_mask = (1LL << bit_size) - 1;
        }
        if ((vtop->r & VT_SYM) &&
            (bt == VT_BYTE ||
             bt == VT_SHORT ||
             bt == VT_DOUBLE ||
             bt == VT_LDOUBLE ||
             bt == VT_LLONG ||
             (bt == VT_INT && bit_size != 32)))
            tcc_error("initializer element is not computable at load time");
        switch(bt) {
        case VT_BOOL:
            vtop->c.i = (vtop->c.i != 0);
        case VT_BYTE:
            *(char *)ptr |= (vtop->c.i & bit_mask) << bit_pos;
            break;
        case VT_SHORT:
            *(short *)ptr |= (vtop->c.i & bit_mask) << bit_pos;
            break;
        case VT_DOUBLE:
            *(double *)ptr = vtop->c.d;
            break;
        case VT_LDOUBLE:
            *(long double *)ptr = vtop->c.ld;
            break;
        case VT_LLONG:
            *(long long *)ptr |= (vtop->c.ll & bit_mask) << bit_pos;
            break;
        default:
            if (vtop->r & VT_SYM) {
                greloc(sec, vtop->sym, c, R_DATA_PTR);
            }
            *(int *)ptr |= (vtop->c.i & bit_mask) << bit_pos;
            break;
        }
        vtop--;
    } else {
        vset(&dtype, VT_LOCAL|VT_LVAL, c);
        vswap();
        vstore();
        vpop();
    }
}

/* put zeros for variable based init */

src/tccgen.c  view on Meta::CPAN

        if (!sec) {
            if (has_init)
                sec = data_section;
            else if (tcc_state->nocommon)
                sec = bss_section;
        }
        if (sec) {
            data_offset = sec->data_offset;
            data_offset = (data_offset + align - 1) & -align;
            addr = data_offset;
            /* very important to increment global pointer at this time
               because initializers themselves can create new initializers */
            data_offset += size;
#ifdef CONFIG_TCC_BCHECK
            /* add padding if bound check */
            if (tcc_state->do_bounds_check)
                data_offset++;
#endif
            sec->data_offset = data_offset;
            /* allocate section space to put the data */
            if (sec->sh_type != SHT_NOBITS && 
                data_offset > sec->data_allocated)
                section_realloc(sec, data_offset);
            /* align section if needed */
            if (align > sec->sh_addralign)
                sec->sh_addralign = align;
        } else {
            addr = 0; /* avoid warning */
        }

        if (v) {
            if (scope != VT_CONST || !sym) {
                sym = sym_push(v, type, r | VT_SYM, 0);
                sym->asm_label = asm_label;
            }
            /* update symbol definition */
            if (sec) {
                put_extern_sym(sym, sec, addr, size);
            } else {
                ElfW(Sym) *esym;
                /* put a common area */
                put_extern_sym(sym, NULL, align, size);
                /* XXX: find a nicer way */
                esym = &((ElfW(Sym) *)symtab_section->data)[sym->c];
                esym->st_shndx = SHN_COMMON;
            }
        } else {
            CValue cval;

            /* push global reference */
            sym = get_sym_ref(type, sec, addr, size);
            cval.ul = 0;
            vsetc(type, VT_CONST | VT_SYM, &cval);
            vtop->sym = sym;
        }
        /* patch symbol weakness */
        if (type->t & VT_WEAK)
            weaken_symbol(sym);
#ifdef CONFIG_TCC_BCHECK
        /* handles bounds now because the symbol must be defined
           before for the relocation */
        if (tcc_state->do_bounds_check) {
            unsigned long *bounds_ptr;

            greloc(bounds_section, sym, bounds_section->data_offset, R_DATA_PTR);
            /* then add global bound info */
            bounds_ptr = section_ptr_add(bounds_section, 2 * sizeof(long));
            bounds_ptr[0] = 0; /* relocated */
            bounds_ptr[1] = size;
        }
#endif
    }
    if (has_init || (type->t & VT_VLA)) {
        decl_initializer(type, sec, addr, 1, 0);
        /* restore parse state if needed */
        if (init_str.str) {
            tok_str_free(init_str.str);
            restore_parse_state(&saved_parse_state);
        }
        /* patch flexible array member size back to -1, */
        /* for possible subsequent similar declarations */
        if (flexible_array)
            flexible_array->type.ref->c = -1;
    }
 no_alloc: ;
}

static void put_func_debug(Sym *sym)
{
    char buf[512];

    /* stabs info */
    /* XXX: we put here a dummy type */
    snprintf(buf, sizeof(buf), "%s:%c1", 
             funcname, sym->type.t & VT_STATIC ? 'f' : 'F');
    put_stabs_r(buf, N_FUN, 0, file->line_num, 0,
                cur_text_section, sym->c);
    /* //gr gdb wants a line at the function */
    put_stabn(N_SLINE, 0, file->line_num, 0); 
    last_ind = 0;
    last_line_num = 0;
}

/* parse an old style function declaration list */
/* XXX: check multiple parameter */
static void func_decl_list(Sym *func_sym)
{
    AttributeDef ad;
    int v;
    Sym *s;
    CType btype, type;

    /* parse each declaration */
    while (tok != '{' && tok != ';' && tok != ',' && tok != TOK_EOF &&
           tok != TOK_ASM1 && tok != TOK_ASM2 && tok != TOK_ASM3) {
        if (!parse_btype(&btype, &ad)) 
            expect("declaration list");
        if (((btype.t & VT_BTYPE) == VT_ENUM ||
             (btype.t & VT_BTYPE) == VT_STRUCT) && 
            tok == ';') {
            /* we accept no variable after */
        } else {
            for(;;) {
                type = btype;
                type_decl(&type, &ad, &v, TYPE_DIRECT);
                /* find parameter in function parameter list */
                s = func_sym->next;
                while (s != NULL) {