aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
Diffstat
-rw-r--r--tcc.c7
-rw-r--r--tccelf.c29
-rw-r--r--x86_64-gen.c126
3 files changed, 128 insertions, 34 deletions
diff --git a/tcc.c b/tcc.c
index 548440d..02da926 100644
--- a/tcc.c
+++ b/tcc.c
@@ -544,9 +544,12 @@ struct TCCState {
FILE *outfile;
#ifdef TCC_TARGET_X86_64
- /* buffer to store jump tables */
+ /* buffer to store jump tables used when the output is memory */
char *jmp_table;
int jmp_table_num;
+ /* buffer to store got tables used when the output is memory */
+ void **got_table;
+ int got_table_num;
#endif
};
@@ -10505,6 +10508,7 @@ TCCState *tcc_new(void)
#ifdef TCC_TARGET_X86_64
s->jmp_table = NULL;
+ s->got_table = NULL;
#endif
return s;
}
@@ -10544,6 +10548,7 @@ void tcc_delete(TCCState *s1)
#ifdef TCC_TARGET_X86_64
tcc_free(s1->jmp_table);
+ tcc_free(s1->got_table);
#endif
tcc_free(s1);
}
diff --git a/tccelf.c b/tccelf.c
index 093f18d..56ee75a 100644
--- a/tccelf.c
+++ b/tccelf.c
@@ -502,6 +502,25 @@ static unsigned long add_jmp_table(TCCState *s1, unsigned long val)
*(unsigned long *)(p + 6) = val;
return (unsigned long)p;
}
+
+#define GOT_TABLE_ENTRY_MAX_NUM 4096
+static unsigned long add_got_table(TCCState *s1, unsigned long val)
+{
+ unsigned long *p;
+ if (!s1->got_table) {
+ int size = sizeof(void *) * GOT_TABLE_ENTRY_MAX_NUM;
+ s1->got_table_num = 0;
+ s1->got_table = (char *)tcc_malloc(size);
+ }
+ if (s1->got_table_num == GOT_TABLE_ENTRY_MAX_NUM) {
+ error("relocating >%d symbols are not supported",
+ GOT_TABLE_ENTRY_MAX_NUM);
+ }
+ p = s1->got_table + s1->got_table_num;
+ s1->got_table_num++;
+ *p = val;
+ return (unsigned long)p;
+}
#endif
/* relocate a given section (CPU dependent) */
@@ -727,11 +746,13 @@ static void relocate_section(TCCState *s1, Section *s)
*(int *)ptr = val;
break;
case R_X86_64_GOTPCREL:
- *(int *)ptr += s1->got->sh_addr - addr;
- /* XXX: is this OK? */
- if (s1->output_type == TCC_OUTPUT_DLL) {
- *(int *)ptr += s1->got_offsets[sym_index] - 4;
+ if (s1->output_type == TCC_OUTPUT_MEMORY) {
+ val = add_got_table(s1, val - rel->r_addend) + rel->r_addend;
+ *(int *)ptr += val - addr;
+ break;
}
+ *(int *)ptr += (s1->got->sh_addr - addr +
+ s1->got_offsets[sym_index] - 4);
break;
case R_X86_64_GOTTPOFF:
*(int *)ptr += val - s1->got->sh_addr;
diff --git a/x86_64-gen.c b/x86_64-gen.c
index 1cbe414..8e39372 100644
--- a/x86_64-gen.c
+++ b/x86_64-gen.c
@@ -53,9 +53,11 @@ enum {
TREG_XMM0 = 3,
TREG_ST0 = 4,
+
+ TREG_MEM = 0x10,
};
-#define REX_BASE(reg) ((reg) >> 3)
+#define REX_BASE(reg) (((reg) >> 3) & 1)
#define REG_VALUE(reg) ((reg) & 7)
int reg_classes[NB_REGS] = {
@@ -205,15 +207,37 @@ static void gen_addrpc32(int r, Sym *sym, int c)
gen_le32(c-4);
}
-/* generate a modrm reference. 'op_reg' contains the addtionnal 3
- opcode bits */
-static void gen_modrm(int op_reg, int r, Sym *sym, int c)
+/* output got address with relocation */
+static void gen_gotpcrel(int r, Sym *sym, int c)
+{
+ Section *sr;
+ ElfW(Rela) *rel;
+ greloc(cur_text_section, sym, ind, R_X86_64_GOTPCREL);
+ sr = cur_text_section->reloc;
+ rel = (ElfW(Rela) *)(sr->data + sr->data_offset - sizeof(ElfW(Rela)));
+ rel->r_addend = -4;
+ gen_le32(0);
+
+ if (c) {
+ /* we use add c, %xxx for displacement */
+ o(0x48 + REX_BASE(r));
+ o(0x81);
+ o(0xc0 + REG_VALUE(r));
+ gen_le32(c);
+ }
+}
+
+static void gen_modrm_impl(int op_reg, int r, Sym *sym, int c, int is_got)
{
- op_reg = op_reg << 3;
+ op_reg = REG_VALUE(op_reg) << 3;
if ((r & VT_VALMASK) == VT_CONST) {
/* constant memory reference */
o(0x05 | op_reg);
- gen_addrpc32(r, sym, c);
+ if (is_got) {
+ gen_gotpcrel(r, sym, c);
+ } else {
+ gen_addrpc32(r, sym, c);
+ }
} else if ((r & VT_VALMASK) == VT_LOCAL) {
/* currently, we use only ebp as base */
if (c == (char)c) {
@@ -223,6 +247,13 @@ static void gen_modrm(int op_reg, int r, Sym *sym, int c)
} else {
oad(0x85 | op_reg, c);
}
+ } else if ((r & VT_VALMASK) >= TREG_MEM) {
+ if (c) {
+ g(0x80 | op_reg | REG_VALUE(r));
+ gen_le32(c);
+ } else {
+ g(0x00 | op_reg | REG_VALUE(r));
+ }
} else {
g(0x00 | op_reg | (r & VT_VALMASK));
}
@@ -230,8 +261,16 @@ static void gen_modrm(int op_reg, int r, Sym *sym, int c)
/* generate a modrm reference. 'op_reg' contains the addtionnal 3
opcode bits */
+static void gen_modrm(int op_reg, int r, Sym *sym, int c)
+{
+ gen_modrm_impl(op_reg, r, sym, c, 0);
+}
+
+/* generate a modrm reference. 'op_reg' contains the addtionnal 3
+ opcode bits */
static void gen_modrm64(int opcode, int op_reg, int r, Sym *sym, int c)
{
+ int is_got;
int rex = 0x48 | (REX_BASE(op_reg) << 2);
if ((r & VT_VALMASK) != VT_CONST &&
(r & VT_VALMASK) != VT_LOCAL) {
@@ -239,23 +278,8 @@ static void gen_modrm64(int opcode, int op_reg, int r, Sym *sym, int c)
}
o(rex);
o(opcode);
- op_reg = REG_VALUE(op_reg) << 3;
- if ((r & VT_VALMASK) == VT_CONST) {
- /* constant memory reference */
- o(0x05 | op_reg);
- gen_addrpc32(r, sym, c);
- } else if ((r & VT_VALMASK) == VT_LOCAL) {
- /* currently, we use only ebp as base */
- if (c == (char)c) {
- /* short reference */
- o(0x45 | op_reg);
- g(c);
- } else {
- oad(0x85 | op_reg, c);
- }
- } else {
- g(0x00 | op_reg | (r & VT_VALMASK));
- }
+ is_got = (op_reg & TREG_MEM) && !(sym->type.t & VT_STATIC);
+ gen_modrm_impl(op_reg, r, sym, c, is_got);
}
@@ -269,6 +293,21 @@ void load(int r, SValue *sv)
ft = sv->type.t;
fc = sv->c.ul;
+ /* we use indirect access via got */
+ if ((fr & VT_VALMASK) == VT_CONST && (fr & VT_SYM) &&
+ (fr & VT_LVAL) && !(sv->sym->type.t & VT_STATIC)) {
+ /* use the result register as a temporal register */
+ int tr = r | TREG_MEM;
+ if (is_float(ft)) {
+ /* we cannot use float registers as a temporal register */
+ tr = get_reg(RC_INT) | TREG_MEM;
+ }
+ gen_modrm64(0x8b, tr, fr, sv->sym, 0);
+
+ /* load from the temporal register */
+ fr = tr | VT_LVAL;
+ }
+
v = fr & VT_VALMASK;
if (fr & VT_LVAL) {
if (v == VT_LLOCAL) {
@@ -305,14 +344,21 @@ void load(int r, SValue *sv)
} else {
if (v == VT_CONST) {
if ((ft & VT_BTYPE) == VT_LLONG) {
+ assert(!(fr & VT_SYM));
o(0x48);
o(0xb8 + REG_VALUE(r)); /* mov $xx, r */
gen_addr64(fr, sv->sym, sv->c.ull);
} else {
if (fr & VT_SYM) {
- o(0x8d48);
- o(0x05 + REG_VALUE(r) * 8); /* lea xx(%rip), r */
- gen_addrpc32(fr, sv->sym, fc);
+ if (sv->sym->type.t & VT_STATIC) {
+ o(0x8d48);
+ o(0x05 + REG_VALUE(r) * 8); /* lea xx(%rip), r */
+ gen_addrpc32(fr, sv->sym, fc);
+ } else {
+ o(0x8b48);
+ o(0x05 + REG_VALUE(r) * 8); /* mov xx(%rip), r */
+ gen_gotpcrel(r, sv->sym, fc);
+ }
} else {
o(0xb8 + REG_VALUE(r)); /* mov $xx, r */
gen_le32(fc);
@@ -362,25 +408,42 @@ void store(int r, SValue *v)
{
int fr, bt, ft, fc;
int op64 = 0;
+ /* store the REX prefix in this variable when PIC is enabled */
+ int pic = 0;
ft = v->type.t;
fc = v->c.ul;
fr = v->r & VT_VALMASK;
bt = ft & VT_BTYPE;
+
+ /* we need to access the variable via got */
+ if (fr == VT_CONST && (v->r & VT_SYM)) {
+ /* mov xx(%rip), %r11 */
+ o(0x1d8b4c);
+ gen_gotpcrel(TREG_R11, v->sym, v->c.ul);
+ pic = is64_type(bt) ? 0x49 : 0x41;
+ }
+
/* XXX: incorrect if float reg to reg */
if (bt == VT_FLOAT) {
- o(0x7e0f66); /* movd */
+ o(0x66);
+ o(pic);
+ o(0x7e0f); /* movd */
r = 0;
} else if (bt == VT_DOUBLE) {
- o(0xd60f66); /* movq */
+ o(0x66);
+ o(pic);
+ o(0xd60f); /* movq */
r = 0;
} else if (bt == VT_LDOUBLE) {
o(0xc0d9); /* fld %st(0) */
+ o(pic);
o(0xdb); /* fstpt */
r = 7;
} else {
if (bt == VT_SHORT)
o(0x66);
+ o(pic);
if (bt == VT_BYTE || bt == VT_BOOL)
o(0x88);
else if (is64_type(bt))
@@ -388,7 +451,12 @@ void store(int r, SValue *v)
else
o(0x89);
}
- if (op64) {
+ if (pic) {
+ /* xxx r, (%r11) where xxx is mov, movq, fld, or etc */
+ if (op64)
+ o(op64);
+ o(3 + (r << 3));
+ } else if (op64) {
if (fr == VT_CONST ||
fr == VT_LOCAL ||
(v->r & VT_LVAL)) {