Cleanups (float consts, sections, symbols)

introduce common_section (SHN_COMMON), factorize some handling in decl_initializer_alloc, add section_add and use it to factorize some code that allocates stuff in sections (at the same time also fixing harmless bugs re section alignment), use init_putv to emit float consts into .data from gv() (fixing an XXX).

Michael Matz committed 9 years ago

Commit c7dbc901 parent 25522e43 files · +42 −79Browse files

Unified · Split

3 files

tcc.h +2 −1
tccelf.c +21 −13
tccgen.c +19 −65

tcc.h+2−1

@@ -470,7 +470,6 @@ typedef struct Sym { · 469 unmodified lines
470	470
471	471	/* special flag, too */
472	472	#define SECTION_ABS ((void *)1)
473		−#define SECTION_COMMON ((void *)2)
474	473
475	474	typedef struct Section {
476	475	unsigned long data_offset; /* current data offset */
@@ -1360,6 +1359,7 @@ typedef struct { · 883 unmodified lines
1360	1359	} Stab_Sym;
1361	1360
1362	1361	ST_DATA Section text_section, data_section, bss_section; / predefined sections */
	1362	+ST_DATA Section *common_section;
1363	1363	ST_DATA Section cur_text_section; / current section where function code is generated */
1364	1364	#ifdef CONFIG_TCC_ASM
1365	1365	ST_DATA Section last_text_section; / to handle .previous asm directive */
@@ -1381,6 +1381,7 @@ ST_FUNC void tccelf_stab_new(TCCState *s); · 15 unmodified lines
1381	1381
1382	1382	ST_FUNC Section new_section(TCCState s1, const char *name, int sh_type, int sh_flags);
1383	1383	ST_FUNC void section_realloc(Section *sec, unsigned long new_size);
	1384	+ST_FUNC size_t section_add(Section *sec, addr_t size, int align);
1384	1385	ST_FUNC void section_ptr_add(Section sec, addr_t size);
1385	1386	ST_FUNC void section_reserve(Section *sec, unsigned long size);
1386	1387	ST_FUNC Section find_section(TCCState s1, const char *name);

tccelf.c+21−13

@@ -27,6 +27,7 @@ · 26 unmodified lines
27	27	/* global variables */
28	28
29	29	ST_DATA Section text_section, data_section, bss_section; / predefined sections */
	30	+ST_DATA Section *common_section;
30	31	ST_DATA Section cur_text_section; / current section where function code is generated */
31	32	#ifdef CONFIG_TCC_ASM
32	33	ST_DATA Section last_text_section; / to handle .previous asm directive */
@@ -55,6 +56,8 @@ ST_FUNC void tccelf_new(TCCState *s) · 22 unmodified lines
55	56	text_section = new_section(s, ".text", SHT_PROGBITS, SHF_ALLOC \| SHF_EXECINSTR);
56	57	data_section = new_section(s, ".data", SHT_PROGBITS, SHF_ALLOC \| SHF_WRITE);
57	58	bss_section = new_section(s, ".bss", SHT_NOBITS, SHF_ALLOC \| SHF_WRITE);
	59	+ common_section = new_section(s, ".common", SHT_NOBITS, SHF_PRIVATE);
	60	+ common_section->sh_num = SHN_COMMON;
58	61
59	62	/* symbols are always generated for linking stage */
60	63	symtab_section = new_symtab(s, ".symtab", SHT_SYMTAB, 0,
@@ -208,17 +211,27 @@ ST_FUNC void section_realloc(Section *sec, unsigned long new_size) · 147 unmodified lines
208	211	sec->data_allocated = size;
209	212	}
210	213
211		−/* reserve at least 'size' bytes in section 'sec' from
212		− sec->data_offset. */
213		−ST_FUNC void section_ptr_add(Section sec, addr_t size)
	214	+/* reserve at least 'size' bytes aligned per 'align' in section
	215	+ 'sec' from current offset, and return the aligned offset */
	216	+ST_FUNC size_t section_add(Section *sec, addr_t size, int align)
214	217	{
215	218	size_t offset, offset1;
216	219
217		− offset = sec->data_offset;
	220	+ offset = (sec->data_offset + align - 1) & -align;
218	221	offset1 = offset + size;
219		− if (offset1 > sec->data_allocated)
	222	+ if (sec->sh_type != SHT_NOBITS && offset1 > sec->data_allocated)
220	223	section_realloc(sec, offset1);
221	224	sec->data_offset = offset1;
	225	+ if (align > sec->sh_addralign)
	226	+ sec->sh_addralign = align;
	227	+ return offset;
	228	+}
	229	+
	230	+/* reserve at least 'size' bytes in section 'sec' from
	231	+ sec->data_offset. */
	232	+ST_FUNC void section_ptr_add(Section sec, addr_t size)
	233	+{
	234	+ size_t offset = section_add(sec, size, 1);
222	235	return sec->data + offset;
223	236	}
224	237
@@ -702,18 +715,13 @@ static void sort_syms(TCCState s1, Section s) · 477 unmodified lines
702	715	ST_FUNC void relocate_common_syms(void)
703	716	{
704	717	ElfW(Sym) *sym;
705		− unsigned long offset, align;
706	718
707	719	for_each_elem(symtab_section, 1, sym, ElfW(Sym)) {
708	720	if (sym->st_shndx == SHN_COMMON) {
709		− /* align symbol */
710		− align = sym->st_value;
711		− offset = bss_section->data_offset;
712		− offset = (offset + align - 1) & -align;
713		− sym->st_value = offset;
	721	+ /* symbol alignment is in st_value for SHN_COMMONs */
	722	+ sym->st_value = section_add(bss_section, sym->st_size,
	723	+ sym->st_value);
714	724	sym->st_shndx = bss_section->sh_num;
715		− offset += sym->st_size;
716		− bss_section->data_offset = offset;
717	725	}
718	726	}
719	727	}

tccgen.c+19−65

@@ -76,6 +76,7 @@ static int is_compatible_types(CType type1, CType type2); · 75 unmodified lines
76	76	static int parse_btype(CType type, AttributeDef ad);
77	77	static CType type_decl(CType type, AttributeDef ad, int v, int td);
78	78	static void parse_expr_type(CType *type);
	79	+static void init_putv(CType type, Section sec, unsigned long c);
79	80	static void decl_initializer(CType type, Section sec, unsigned long c, int first, int size_only);
80	81	static void block(int bsym, int csym, int is_expr);
81	82	static void decl_initializer_alloc(CType type, AttributeDef ad, int r, int has_init, int v, int scope);
@@ -302,8 +303,6 @@ ST_FUNC void put_extern_sym2(Sym sym, Section section, · 220 unmodified lines
302	303	sh_num = SHN_UNDEF;
303	304	else if (section == SECTION_ABS)
304	305	sh_num = SHN_ABS;
305		− else if (section == SECTION_COMMON)
306		− sh_num = SHN_COMMON;
307	306	else
308	307	sh_num = section->sh_num;
309	308
@@ -1065,7 +1064,7 @@ static void gbound(void) · 755 unmodified lines
1065	1064	register value (such as structures). */
1066	1065	ST_FUNC int gv(int rc)
1067	1066	{
1068		− int r, bit_pos, bit_size, size, align, i;
	1067	+ int r, bit_pos, bit_size, size, align;
1069	1068	int rc2;
1070	1069
1071	1070	/* NOTE: get_reg can modify vstack[] */
@@ -1096,44 +1095,15 @@ ST_FUNC int gv(int rc) · 24 unmodified lines
1096	1095	} else {
1097	1096	if (is_float(vtop->type.t) &&
1098	1097	(vtop->r & (VT_VALMASK \| VT_LVAL)) == VT_CONST) {
1099		− Sym *sym;
1100		− int *ptr;
1101	1098	unsigned long offset;
1102		−#if defined(TCC_TARGET_ARM) && !defined(TCC_ARM_VFP)
1103		− CValue check;
1104		−#endif
1105		−
1106		− /* XXX: unify with initializers handling ? */
1107	1099	/* CPUs usually cannot use float constants, so we store them
1108	1100	generically in data segment */
1109	1101	size = type_size(&vtop->type, &align);
1110		− offset = (data_section->data_offset + align - 1) & -align;
1111		− data_section->data_offset = offset;
1112		− /* XXX: not portable yet */
1113		−#if defined(__i386__) \|\| defined(__x86_64__)
1114		− /* Zero pad x87 tenbyte long doubles */
1115		− if (size == LDOUBLE_SIZE) {
1116		− vtop->c.tab[2] &= 0xffff;
1117		−#if LDOUBLE_SIZE == 16
1118		− vtop->c.tab[3] = 0;
1119		−#endif
1120		− }
1121		−#endif
1122		− ptr = section_ptr_add(data_section, size);
1123		− size = size >> 2;
1124		−#if defined(TCC_TARGET_ARM) && !defined(TCC_ARM_VFP)
1125		− check.d = 1;
1126		− if(check.tab[0])
1127		− for(i=0;i<size;i++)
1128		− ptr[i] = vtop->c.tab[size-1-i];
1129		− else
1130		−#endif
1131		− for(i=0;i<size;i++)
1132		− ptr[i] = vtop->c.tab[i];
1133		− sym = get_sym_ref(&vtop->type, data_section, offset, size << 2);
1134		− vtop->r \|= VT_LVAL \| VT_SYM;
1135		− vtop->sym = sym;
1136		− vtop->c.i = 0;
	1102	+ offset = section_add(data_section, size, align);
	1103	+ vpush_ref(&vtop->type, data_section, offset, size);
	1104	+ vswap();
	1105	+ init_putv(&vtop->type, data_section, offset);
	1106	+ vtop->r \|= VT_LVAL;
1137	1107	}
1138	1108	#ifdef CONFIG_TCC_BCHECK
1139	1109	if (vtop->r & VT_MUSTBOUND)
@@ -4351,7 +4321,7 @@ ST_FUNC void unary(void) · 3211 unmodified lines
4351	4321	t = VT_LLONG;
4352	4322	goto push_tokc;
4353	4323	case TOK_CULLONG:
4354		− t =VT_LLONG \| VT_UNSIGNED;
	4324	+ t = VT_LLONG \| VT_UNSIGNED;
4355	4325	goto push_tokc;
4356	4326	case TOK_CFLOAT:
4357	4327	t = VT_FLOAT;
@@ -6098,9 +6068,7 @@ static void init_putv(CType type, Section sec, unsigned long c) · 1740 unmodified lines
6098	6068	gen_assign_cast(&dtype);
6099	6069	bt = type->t & VT_BTYPE;
6100	6070	size = type_size(type, &align);
6101		− if (c + size > sec->data_allocated) {
6102		− section_realloc(sec, c + size);
6103		− }
	6071	+ section_reserve(sec, c + size);
6104	6072	ptr = sec->data + c;
6105	6073	/* XXX: make code faster ? */
6106	6074	if (!(type->t & VT_BITFIELD)) {
@@ -6190,6 +6158,9 @@ static void init_putv(CType type, Section sec, unsigned long c) · 83 unmodified lines
6190	6158	case VT_SHORT:
6191	6159	(short )ptr \|= (vtop->c.i & bit_mask) << bit_pos;
6192	6160	break;
	6161	+ case VT_FLOAT:
	6162	+ (float)ptr = vtop->c.f;
	6163	+ break;
6193	6164	case VT_DOUBLE:
6194	6165	(double )ptr = vtop->c.d;
6195	6166	break;
@@ -6475,7 +6446,7 @@ static void decl_initializer(CType type, Section sec, unsigned long c, · 279 unmodified lines
6475	6446	static void decl_initializer_alloc(CType type, AttributeDef ad, int r,
6476	6447	int has_init, int v, int scope)
6477	6448	{
6478		− int size, align, addr, data_offset;
	6449	+ int size, align, addr;
6479	6450	ParseState saved_parse_state = {0};
6480	6451	TokenString *init_str = NULL;
6481	6452	Section *sec;
@@ -6624,41 +6595,24 @@ static void decl_initializer_alloc(CType type, AttributeDef ad, int r, · 142 unmodified lines
6624	6595	}
6625	6596
6626	6597	if (sec) {
6627		− data_offset = sec->data_offset;
6628		− data_offset = (data_offset + align - 1) & -align;
6629		− addr = data_offset;
6630		− /* very important to increment global pointer at this time
6631		− because initializers themselves can create new initializers */
6632		− data_offset += size;
	6598	+ addr = section_add(sec, size, align);
6633	6599	#ifdef CONFIG_TCC_BCHECK
6634	6600	/* add padding if bound check */
6635	6601	if (tcc_state->do_bounds_check)
6636		− data_offset++;
	6602	+ section_add(sec, 1, 1);
6637	6603	#endif
6638		− sec->data_offset = data_offset;
6639		− /* allocate section space to put the data */
6640		− if (sec->sh_type != SHT_NOBITS &&
6641		− data_offset > sec->data_allocated)
6642		− section_realloc(sec, data_offset);
6643		− /* align section if needed */
6644		− if (align > sec->sh_addralign)
6645		− sec->sh_addralign = align;
6646	6604	} else {
6647		− addr = 0; /* avoid warning */
	6605	+ addr = align; /* SHN_COMMON is special, symbol value is align */
	6606	+ sec = common_section;
6648	6607	}
6649	6608
6650	6609	if (v) {
6651		− if (scope != VT_CONST \|\| !sym) {
	6610	+ if (!sym) {
6652	6611	sym = sym_push(v, type, r \| VT_SYM, 0);
6653	6612	sym->asm_label = ad->asm_label;
6654	6613	}
6655	6614	/* update symbol definition */
6656		− if (sec) {
6657		− put_extern_sym(sym, sec, addr, size);
6658		− } else {
6659		− put_extern_sym(sym, SECTION_COMMON, align, size);
6660		− }
6661		−
	6615	+ put_extern_sym(sym, sec, addr, size);
6662	6616	} else {
6663	6617	/* push global reference */
6664	6618	sym = get_sym_ref(type, sec, addr, size);

Cleanups (float consts, sections, symbols)

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