/*
* CIL code generator for TCC
*
* Copyright (c) 2002 Fabrice Bellard
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
/* number of available registers */
#define NB_REGS 3
/* a register can belong to several classes. The classes must be
sorted from more general to more precise (see gv2() code which does
assumptions on it). */
#define RC_ST 0x0001 /* any stack entry */
#define RC_ST0 0x0002 /* top of stack */
#define RC_ST1 0x0004 /* top - 1 */
#define RC_INT RC_ST
#define RC_FLOAT RC_ST
#define RC_IRET RC_ST0 /* function return: integer register */
#define RC_LRET RC_ST0 /* function return: second integer register */
#define RC_FRET RC_ST0 /* function return: float register */
/* pretty names for the registers */
enum {
REG_ST0 = 0,
REG_ST1,
REG_ST2,
};
const int reg_classes[NB_REGS] = {
/* ST0 */ RC_ST | RC_ST0,
/* ST1 */ RC_ST | RC_ST1,
/* ST2 */ RC_ST,
};
/* return registers for function */
#define REG_IRET REG_ST0 /* single word int return register */
#define REG_LRET REG_ST0 /* second word return register (for long long) */
#define REG_FRET REG_ST0 /* float return register */
/* defined if function parameters must be evaluated in reverse order */
/* #define INVERT_FUNC_PARAMS */
/* defined if structures are passed as pointers. Otherwise structures
are directly pushed on stack. */
/* #define FUNC_STRUCT_PARAM_AS_PTR */
/* pointer size, in bytes */
#define PTR_SIZE 4
/* long double size and alignment, in bytes */
#define LDOUBLE_SIZE 8
#define LDOUBLE_ALIGN 8
/* function call context */
typedef struct GFuncContext {
int func_call; /* func call type (FUNC_STDCALL or FUNC_CDECL) */
} GFuncContext;
/******************************************************/
/* opcode definitions */
#define IL_OP_PREFIX 0xFE
enum ILOPCodes {
#define OP(name, str, n) IL_OP_ ## name = n,
#include "il-opcodes.h"
#undef OP
};
char *il_opcodes_str[] = {
#define OP(name, str, n) [n] = str,
#include "il-opcodes.h"
#undef OP
};
/******************************************************/
/* arguments variable numbers start from there */
#define ARG_BASE 0x70000000
static FILE *il_outfile;
static void out_byte(int c)
{
*(char *)ind++ = c;
}
static void out_le32(int c)
{
out_byte(c);
out_byte(c >> 8);
out_byte(c >> 16);
out_byte(c >> 24);
}
static void init_outfile(void)
{
if (!il_outfile) {
il_outfile = stdout;
fprintf(il_outfile,
".assembly extern mscorlib\n"
"{\n"
".ver 1:0:2411:0\n"
"}\n\n");
}
}
static void out_op1(int op)
{
if (op & 0x100)
out_byte(IL_OP_PREFIX);
out_byte(op & 0xff);
}
/* output an opcode with prefix */
static void out_op(int op)
{
out_op1(op);
fprintf(il_outfile, " %s\n", il_opcodes_str[op]);
}
static void out_opb(int op, int c)
{
out_op1(op);
out_byte(c);
fprintf(il_outfile, " %s %d\n", il_opcodes_str[op], c);
}
static void out_opi(int op, int c)
{
out_op1(op);
out_le32(c);
fprintf(il_outfile, " %s 0x%x\n", il_opcodes_str[op], c);
}
/* XXX: not complete */
static void il_type_to_str(char *buf, int buf_size,
int t, const char *varstr)
{
int bt;
Sym *s, *sa;
char buf1[256];
const char *tstr;
t = t & VT_TYPE;
bt = t & VT_BTYPE;
buf[0] = '\0';
if (t & VT_UNSIGNED)
pstrcat(buf, buf_size, "unsigned ");
switch(bt) {
case VT_VOID:
tstr = "void";
goto add_tstr;
case VT_BOOL:
tstr = "bool";
goto add_tstr;
case VT_BYTE:
tstr = "int8";
goto add_tstr;
case VT_SHORT:
tstr = "int16";
goto add_tstr;
case VT_ENUM:
case VT_INT:
case VT_LONG:
tstr = "int32";
goto add_tstr;
case VT_LLONG:
tstr = "int64";
goto add_tstr;
case VT_FLOAT:
tstr = "float32";
goto add_tstr;
case VT_DOUBLE:
case VT_LDOUBLE:
tstr = "float64";
add_tstr:
pstrcat(buf, buf_size, tstr);
break;
case VT_STRUCT:
tcc_error("structures not handled yet");
break;
case VT_FUNC:
s = sym_find((unsigned)t >> VT_STRUCT_SHIFT);
il_type_to_str(buf, buf_size, s->t, varstr);
pstrcat(buf, buf_size, "(");
sa = s->next;
while (sa != NULL) {
il_type_to_str(buf1, sizeof(buf1), sa->t, NULL);
pstrcat(buf, buf_size, buf1);
sa = sa->next;
if (sa)
pstrcat(buf, buf_size, ", ");
}
pstrcat(buf, buf_size, ")");
goto no_var;
case VT_PTR:
s = sym_find((unsigned)t >> VT_STRUCT_SHIFT);
pstrcpy(buf1, sizeof(buf1), "*");
if (varstr)
pstrcat(buf1, sizeof(buf1), varstr);
il_type_to_str(buf, buf_size, s->t, buf1);
goto no_var;
}
if (varstr) {
pstrcat(buf, buf_size, " ");
pstrcat(buf, buf_size, varstr);
}
no_var: ;
}
/* patch relocation entry with value 'val' */
void greloc_patch1(Reloc *p, int val)
{
}
/* output a symbol and patch all calls to it */
void gsym_addr(t, a)
{
}
/* output jump and return symbol */
static int out_opj(int op, int c)
{
out_op1(op);
out_le32(0);
if (c == 0) {
c = ind - (int)cur_text_section->data;
}
fprintf(il_outfile, " %s L%d\n", il_opcodes_str[op], c);
return c;
}
void gsym(int t)
{
fprintf(il_outfile, "L%d:\n", t);
}
/* load 'r' from value 'sv' */
void load(int r, SValue *sv)
{
int v, fc, ft;
v = sv->r & VT_VALMASK;
fc = sv->c.i;
ft = sv->t;
if (sv->r & VT_LVAL) {
if (v == VT_LOCAL) {
if (fc >= ARG_BASE) {
fc -= ARG_BASE;
if (fc >= 0 && fc <= 4) {
out_op(IL_OP_LDARG_0 + fc);
} else if (fc <= 0xff) {
out_opb(IL_OP_LDARG_S, fc);
} else {
out_opi(IL_OP_LDARG, fc);
}
} else {
if (fc >= 0 && fc <= 4) {
out_op(IL_OP_LDLOC_0 + fc);
} else if (fc <= 0xff) {
out_opb(IL_OP_LDLOC_S, fc);
} else {
out_opi(IL_OP_LDLOC, fc);
}
}
} else if (v == VT_CONST) {
/* XXX: handle globals */
out_opi(IL_OP_LDSFLD, 0);
} else {
if ((ft & VT_BTYPE) == VT_FLOAT) {
out_op(IL_OP_LDIND_R4);
} else if ((ft & VT_BTYPE) == VT_DOUBLE) {
out_op(IL_OP_LDIND_R8);
} else if ((ft & VT_BTYPE) == VT_LDOUBLE) {
out_op(IL_OP_LDIND_R8);
} else if ((ft & VT_TYPE) == VT_BYTE)
out_op(IL_OP_LDIND_I1);
else if ((ft & VT_TYPE) == (VT_BYTE | VT_UNSIGNED))
out_op(IL_OP_LDIND_U1);
else if ((ft & VT_TYPE) == VT_SHORT)
out_op(IL_OP_LDIND_I2);
else if ((ft & VT_TYPE) == (VT_SHORT | VT_UNSIGNED))
out_op(IL_OP_LDIND_U2);
else
out_op(IL_OP_LDIND_I4);
}
} else {
if (v == VT_CONST) {
/* XXX: handle globals */
if (fc >= -1 && fc <= 8) {
out_op(IL_OP_LDC_I4_M1 + fc + 1);
} else {
out_opi(IL_OP_LDC_I4, fc);
}
} else if (v == VT_LOCAL) {
if (fc >= ARG_BASE) {
fc -= ARG_BASE;
if (fc <= 0xff) {
out_opb(IL_OP_LDARGA_S, fc);
} else {
out_opi(IL_OP_LDARGA, fc);
}
} else {
if (fc <= 0xff) {
out_opb(IL_OP_LDLOCA_S, fc);
} else {
out_opi(IL_OP_LDLOCA, fc);
}
}
} else {
/* XXX: do it */
}
}
}
/* store register 'r' in lvalue 'v' */
void store(int r, SValue *sv)
{
int v, fc, ft;
v = sv->r & VT_VALMASK;
fc = sv->c.i;
ft = sv->t;
if (v == VT_LOCAL) {
if (fc >= ARG_BASE) {
fc -= ARG_BASE;
/* XXX: check IL arg store semantics */
if (fc <= 0xff) {
out_opb(IL_OP_STARG_S, fc);
} else {
out_opi(IL_OP_STARG, fc);
}
} else {
if (fc >= 0 && fc <= 4) {
out_op(IL_OP_STLOC_0 + fc);
} else if (fc <= 0xff) {
out_opb(IL_OP_STLOC_S, fc);
} else {
out_opi(IL_OP_STLOC, fc);
}
}
} else if (v == VT_CONST) {
/* XXX: handle globals */
out_opi(IL_OP_STSFLD, 0);
} else {
if ((ft & VT_BTYPE) == VT_FLOAT)
out_op(IL_OP_STIND_R4);
else if ((ft & VT_BTYPE) == VT_DOUBLE)
out_op(IL_OP_STIND_R8);
else if ((ft & VT_BTYPE) == VT_LDOUBLE)
out_op(IL_OP_STIND_R8);
else if ((ft & VT_BTYPE) == VT_BYTE)
out_op(IL_OP_STIND_I1);
else if ((ft & VT_BTYPE) == VT_SHORT)
out_op(IL_OP_STIND_I2);
else
out_op(IL_OP_STIND_I4);
}
}
/* start function call and return function call context */
void gfunc_start(GFuncContext *c, int func_call)
{
c->func_call = func_call;
}
/* push function parameter which is in (vtop->t, vtop->c). Stack entry
is then popped. */
void gfunc_param(GFuncContext *c)
{
if ((vtop->t & VT_BTYPE) == VT_STRUCT) {
tcc_error("structures passed as value not handled yet");
} else {
/* simply push on stack */
gv(RC_ST0);
}
vtop--;
}
/* generate function call with address in (vtop->t, vtop->c) and free function
context. Stack entry is popped */
void gfunc_call(GFuncContext *c)
{
char buf[1024];
if ((vtop->r & (VT_VALMASK | VT_LVAL)) == VT_CONST) {
/* XXX: more info needed from tcc */
il_type_to_str(buf, sizeof(buf), vtop->t, "xxx");
fprintf(il_outfile, " call %s\n", buf);
} else {
/* indirect call */
gv(RC_INT);
il_type_to_str(buf, sizeof(buf), vtop->t, NULL);
fprintf(il_outfile, " calli %s\n", buf);
}
vtop--;
}
/* generate function prolog of type 't' */
void gfunc_prolog(int t)
{
int addr, u, func_call;
Sym *sym;
char buf[1024];
init_outfile();
/* XXX: pass function name to gfunc_prolog */
il_type_to_str(buf, sizeof(buf), t, funcname);
fprintf(il_outfile, ".method static %s il managed\n", buf);
fprintf(il_outfile, "{\n");
/* XXX: cannot do better now */
fprintf(il_outfile, " .maxstack %d\n", NB_REGS);
fprintf(il_outfile, " .locals (int32, int32, int32, int32, int32, int32, int32, int32)\n");
if (!strcmp(funcname, "main"))
fprintf(il_outfile, " .entrypoint\n");
sym = sym_find((unsigned)t >> VT_STRUCT_SHIFT);
func_call = sym->r;
addr = ARG_BASE;
/* if the function returns a structure, then add an
implicit pointer parameter */
func_vt = sym->t;
if ((func_vt & VT_BTYPE) == VT_STRUCT) {
func_vc = addr;
addr++;
}
/* define parameters */
while ((sym = sym->next) != NULL) {
u = sym->t;
sym_push(sym->v & ~SYM_FIELD, u,
VT_LOCAL | lvalue_type(sym->type.t), addr);
addr++;
}
}
/* generate function epilog */
void gfunc_epilog(void)
{
out_op(IL_OP_RET);
fprintf(il_outfile, "}\n\n");
}
/* generate a jump to a label */
int gjmp(int t)
{
return out_opj(IL_OP_BR, t);
}
/* generate a jump to a fixed address */
void gjmp_addr(int a)
{
/* XXX: handle syms */
out_opi(IL_OP_BR, a);
}
/* generate a test. set 'inv' to invert test. Stack entry is popped */
int gtst(int inv, int t)
{
int v, *p, c;
v = vtop->r & VT_VALMASK;
if (v == VT_CMP) {
c = vtop->c.i ^ inv;
switch(c) {
case TOK_EQ:
c = IL_OP_BEQ;
break;
case TOK_NE:
c = IL_OP_BNE_UN;
break;
case TOK_LT:
c = IL_OP_BLT;
break;
case TOK_LE:
c = IL_OP_BLE;
break;
case TOK_GT:
c = IL_OP_BGT;
break;
case TOK_GE:
c = IL_OP_BGE;
break;
case TOK_ULT:
c = IL_OP_BLT_UN;
break;
case TOK_ULE:
c = IL_OP_BLE_UN;
break;
case TOK_UGT:
c = IL_OP_BGT_UN;
break;
case TOK_UGE:
c = IL_OP_BGE_UN;
break;
}
t = out_opj(c, t);
} else if (v == VT_JMP || v == VT_JMPI) {
/* && or || optimization */
if ((v & 1) == inv) {
/* insert vtop->c jump list in t */
p = &vtop->c.i;
while (*p != 0)
p = (int *)*p;
*p = t;
t = vtop->c.i;
} else {
t = gjmp(t);
gsym(vtop->c.i);
}
} else {
if (is_float(vtop->t)) {
vpushi(0);
gen_op(TOK_NE);
}
if ((vtop->r & (VT_VALMASK | VT_LVAL | VT_FORWARD)) == VT_CONST) {
/* constant jmp optimization */
if ((vtop->c.i != 0) != inv)
t = gjmp(t);
} else {
v = gv(RC_INT);
t = out_opj(IL_OP_BRTRUE - inv, t);
}
}
vtop--;
return t;
}
/* generate an integer binary operation */
void gen_opi(int op)
{
gv2(RC_ST1, RC_ST0);
switch(op) {
case '+':
out_op(IL_OP_ADD);
goto std_op;
case '-':
out_op(IL_OP_SUB);
goto std_op;
case '&':
out_op(IL_OP_AND);
goto std_op;
case '^':
out_op(IL_OP_XOR);
goto std_op;
case '|':
out_op(IL_OP_OR);
goto std_op;
case '*':
out_op(IL_OP_MUL);
goto std_op;
case TOK_SHL:
out_op(IL_OP_SHL);
goto std_op;
case TOK_SHR:
out_op(IL_OP_SHR_UN);
goto std_op;
case TOK_SAR:
out_op(IL_OP_SHR);
goto std_op;
case '/':
case TOK_PDIV:
out_op(IL_OP_DIV);
goto std_op;
case TOK_UDIV:
out_op(IL_OP_DIV_UN);
goto std_op;
case '%':
out_op(IL_OP_REM);
goto std_op;
case TOK_UMOD:
out_op(IL_OP_REM_UN);
std_op:
vtop--;
vtop[0].r = REG_ST0;
break;
case TOK_EQ:
case TOK_NE:
case TOK_LT:
case TOK_LE:
case TOK_GT:
case TOK_GE:
case TOK_ULT:
case TOK_ULE:
case TOK_UGT:
case TOK_UGE:
vtop--;
vtop[0].r = VT_CMP;
vtop[0].c.i = op;
break;
}
}
/* generate a floating point operation 'v = t1 op t2' instruction. The
two operands are guaranted to have the same floating point type */
void gen_opf(int op)
{
/* same as integer */
gen_opi(op);
}
/* convert integers to fp 't' type. Must handle 'int', 'unsigned int'
and 'long long' cases. */
void gen_cvt_itof(int t)
{
gv(RC_ST0);
if (t == VT_FLOAT)
out_op(IL_OP_CONV_R4);
else
out_op(IL_OP_CONV_R8);
}
/* convert fp to int 't' type */
/* XXX: handle long long case */
void gen_cvt_ftoi(int t)
{
gv(RC_ST0);
switch(t) {
case VT_INT | VT_UNSIGNED:
out_op(IL_OP_CONV_U4);
break;
case VT_LLONG:
out_op(IL_OP_CONV_I8);
break;
case VT_LLONG | VT_UNSIGNED:
out_op(IL_OP_CONV_U8);
break;
default:
out_op(IL_OP_CONV_I4);
break;
}
}
/* convert from one floating point type to another */
void gen_cvt_ftof(int t)
{
gv(RC_ST0);
if (t == VT_FLOAT) {
out_op(IL_OP_CONV_R4);
} else {
out_op(IL_OP_CONV_R8);
}
}
/* end of CIL code generator */
/*************************************************************/