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sourcemod/sourcepawn/compiler/sc6.c

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/* Pawn compiler - Binary code generation (the "assembler")
*
* Copyright (c) ITB CompuPhase, 1997-2006
*
* This software is provided "as-is", without any express or implied warranty.
* In no event will the authors be held liable for any damages arising from
* the use of this software.
*
* Permission is granted to anyone to use this software for any purpose,
* including commercial applications, and to alter it and redistribute it
* freely, subject to the following restrictions:
*
* 1. The origin of this software must not be misrepresented; you must not
* claim that you wrote the original software. If you use this software in
* a product, an acknowledgment in the product documentation would be
* appreciated but is not required.
* 2. Altered source versions must be plainly marked as such, and must not be
* misrepresented as being the original software.
* 3. This notice may not be removed or altered from any source distribution.
*
* Version: $Id$
*/
#include <assert.h>
#include <stdio.h>
#include <stdlib.h> /* for macro max() */
#include <stddef.h> /* for macro offsetof() */
#include <string.h>
#include <ctype.h>
#if defined FORTIFY
#include <alloc/fortify.h>
#endif
#include "lstring.h"
#include "sc.h"
#include "amxdbg.h"
#if defined LINUX || defined __FreeBSD__ || defined __OpenBSD__
#include <sclinux.h>
#endif
static void append_dbginfo(FILE *fout);
typedef cell (*OPCODE_PROC)(FILE *fbin,char *params,cell opcode);
typedef struct {
cell opcode;
char *name;
int segment; /* sIN_CSEG=parse in cseg, sIN_DSEG=parse in dseg */
OPCODE_PROC func;
} OPCODEC;
static cell codeindex; /* similar to "code_idx" */
static cell *lbltab; /* label table */
static int writeerror;
static int bytes_in, bytes_out;
static jmp_buf compact_err;
/* apparently, strtol() does not work correctly on very large (unsigned)
* hexadecimal values */
static ucell hex2long(const char *s,char **n)
{
ucell result=0L;
int negate=FALSE;
int digit;
/* ignore leading whitespace */
while (*s==' ' || *s=='\t')
s++;
/* allow a negation sign to create the two's complement of numbers */
if (*s=='-') {
negate=TRUE;
s++;
} /* if */
assert((*s>='0' && *s<='9') || (*s>='a' && *s<='f') || (*s>='a' && *s<='f'));
for ( ;; ) {
if (*s>='0' && *s<='9')
digit=*s-'0';
else if (*s>='a' && *s<='f')
digit=*s-'a' + 10;
else if (*s>='A' && *s<='F')
digit=*s-'A' + 10;
else
break; /* probably whitespace */
result=(result<<4) | digit;
s++;
} /* for */
if (n!=NULL)
*n=(char*)s;
if (negate)
result=(~result)+1; /* take two's complement of the result */
return (ucell)result;
}
static ucell getparam(const char *s,char **n)
{
ucell result=0;
for ( ;; ) {
result+=hex2long(s,(char**)&s);
if (*s!='+')
break;
s++;
} /* for */
if (n!=NULL)
*n=(char*)s;
return result;
}
#if BYTE_ORDER==BIG_ENDIAN
static uint16_t *align16(uint16_t *v)
{
unsigned char *s = (unsigned char *)v;
unsigned char t;
/* swap two bytes */
t=s[0];
s[0]=s[1];
s[1]=t;
return v;
}
static uint32_t *align32(uint32_t *v)
{
unsigned char *s = (unsigned char *)v;
unsigned char t;
/* swap outer two bytes */
t=s[0];
s[0]=s[3];
s[3]=t;
/* swap inner two bytes */
t=s[1];
s[1]=s[2];
s[2]=t;
return v;
}
#if PAWN_CELL_SIZE>=64
static uint64_t *align64(uint64_t *v)
{
unsigned char *s = (unsigned char *)v;
unsigned char t;
t=s[0];
s[0]=s[7];
s[7]=t;
t=s[1];
s[1]=s[6];
s[6]=t;
t=s[2];
s[2]=s[5];
s[5]=t;
t=s[3];
s[3]=s[4];
s[4]=t;
return v;
}
#endif
#if PAWN_CELL_SIZE==16
#define aligncell(v) align16(v)
#elif PAWN_CELL_SIZE==32
#define aligncell(v) align32(v)
#elif PAWN_CELL_SIZE==64
#define aligncell(v) align64(v)
#endif
#else
#define align16(v) (v)
#define align32(v) (v)
#define aligncell(v) (v)
#endif
static char *skipwhitespace(char *str)
{
while (isspace(*str))
str++;
return str;
}
static char *stripcomment(char *str)
{
char *ptr=strchr(str,';');
if (ptr!=NULL) {
*ptr++='\n'; /* terminate the line, but leave the '\n' */
*ptr='\0';
} /* if */
return str;
}
static void write_encoded(FILE *fbin,ucell *c,int num)
{
#if PAWN_CELL_SIZE == 16
#define ENC_MAX 3 /* a 16-bit cell is encoded in max. 3 bytes */
#define ENC_MASK 0x03 /* after 2x7 bits, 2 bits remain to make 16 bits */
#elif PAWN_CELL_SIZE == 32
#define ENC_MAX 5 /* a 32-bit cell is encoded in max. 5 bytes */
#define ENC_MASK 0x0f /* after 4x7 bits, 4 bits remain to make 32 bits */
#elif PAWN_CELL_SIZE == 64
#define ENC_MAX 10 /* a 32-bit cell is encoded in max. 10 bytes */
#define ENC_MASK 0x01 /* after 9x7 bits, 1 bit remains to make 64 bits */
#endif
assert(fbin!=NULL);
while (num-->0) {
if (sc_compress) {
ucell p=(ucell)*c;
unsigned char t[ENC_MAX];
unsigned char code;
int index;
for (index=0; index<ENC_MAX; index++) {
t[index]=(unsigned char)(p & 0x7f); /* store 7 bits */
p>>=7;
} /* for */
/* skip leading zeros */
while (index>1 && t[index-1]==0 && (t[index-2] & 0x40)==0)
index--;
/* skip leading -1s */
if (index==ENC_MAX && t[index-1]==ENC_MASK && (t[index-2] & 0x40)!=0)
index--;
while (index>1 && t[index-1]==0x7f && (t[index-2] & 0x40)!=0)
index--;
/* write high byte first, write continuation bits */
assert(index>0);
while (index-->0) {
code=(unsigned char)((index==0) ? t[index] : (t[index]|0x80));
writeerror |= !pc_writebin(fbin,&code,1);
bytes_out++;
} /* while */
bytes_in+=sizeof *c;
assert(AMX_COMPACTMARGIN>2);
if (bytes_out-bytes_in>=AMX_COMPACTMARGIN-2)
longjmp(compact_err,1);
} else {
assert((pc_lengthbin(fbin) % sizeof(cell)) == 0);
writeerror |= !pc_writebin(fbin,aligncell(c),sizeof *c);
} /* if */
c++;
} /* while */
}
#if defined __BORLANDC__ || defined __WATCOMC__
#pragma argsused
#endif
static cell noop(FILE *fbin,char *params,cell opcode)
{
return 0;
}
#if defined __BORLANDC__ || defined __WATCOMC__
#pragma argsused
#endif
static cell set_currentfile(FILE *fbin,char *params,cell opcode)
{
fcurrent=(short)getparam(params,NULL);
return 0;
}
#if defined __BORLANDC__ || defined __WATCOMC__
#pragma argsused
#endif
static cell parm0(FILE *fbin,char *params,cell opcode)
{
if (fbin!=NULL)
write_encoded(fbin,(ucell*)&opcode,1);
return opcodes(1);
}
static cell parm1(FILE *fbin,char *params,cell opcode)
{
ucell p=getparam(params,NULL);
if (fbin!=NULL) {
write_encoded(fbin,(ucell*)&opcode,1);
write_encoded(fbin,&p,1);
} /* if */
return opcodes(1)+opargs(1);
}
static cell parm2(FILE *fbin,char *params,cell opcode)
{
ucell p1=getparam(params,&params);
ucell p2=getparam(params,NULL);
if (fbin!=NULL) {
write_encoded(fbin,(ucell*)&opcode,1);
write_encoded(fbin,&p1,1);
write_encoded(fbin,&p2,1);
} /* if */
return opcodes(1)+opargs(2);
}
static cell parm3(FILE *fbin,char *params,cell opcode)
{
ucell p1=getparam(params,&params);
ucell p2=getparam(params,&params);
ucell p3=getparam(params,NULL);
if (fbin!=NULL) {
write_encoded(fbin,(ucell*)&opcode,1);
write_encoded(fbin,&p1,1);
write_encoded(fbin,&p2,1);
write_encoded(fbin,&p3,1);
} /* if */
return opcodes(1)+opargs(3);
}
static cell parm4(FILE *fbin,char *params,cell opcode)
{
ucell p1=getparam(params,&params);
ucell p2=getparam(params,&params);
ucell p3=getparam(params,&params);
ucell p4=getparam(params,NULL);
if (fbin!=NULL) {
write_encoded(fbin,(ucell*)&opcode,1);
write_encoded(fbin,&p1,1);
write_encoded(fbin,&p2,1);
write_encoded(fbin,&p3,1);
write_encoded(fbin,&p4,1);
} /* if */
return opcodes(1)+opargs(4);
}
static cell parm5(FILE *fbin,char *params,cell opcode)
{
ucell p1=getparam(params,&params);
ucell p2=getparam(params,&params);
ucell p3=getparam(params,&params);
ucell p4=getparam(params,&params);
ucell p5=getparam(params,NULL);
if (fbin!=NULL) {
write_encoded(fbin,(ucell*)&opcode,1);
write_encoded(fbin,&p1,1);
write_encoded(fbin,&p2,1);
write_encoded(fbin,&p3,1);
write_encoded(fbin,&p4,1);
write_encoded(fbin,&p5,1);
} /* if */
return opcodes(1)+opargs(5);
}
#if defined __BORLANDC__ || defined __WATCOMC__
#pragma argsused
#endif
static cell do_dump(FILE *fbin,char *params,cell opcode)
{
ucell p;
int num = 0;
while (*params!='\0') {
p=getparam(params,&params);
if (fbin!=NULL)
write_encoded(fbin,&p,1);
num++;
while (isspace(*params))
params++;
} /* while */
return num*sizeof(cell);
}
static cell do_call(FILE *fbin,char *params,cell opcode)
{
char name[sNAMEMAX+1];
int i;
symbol *sym;
ucell p;
for (i=0; !isspace(*params); i++,params++) {
assert(*params!='\0');
assert(i<sNAMEMAX);
name[i]=*params;
} /* for */
name[i]='\0';
if (name[0]=='l' && name[1]=='.') {
/* this is a label, not a function symbol */
i=(int)hex2long(name+2,NULL);
assert(i>=0 && i<sc_labnum);
if (fbin!=NULL) {
assert(lbltab!=NULL);
p=lbltab[i];
} /* if */
} else {
/* look up the function address; note that the correct file number must
* already have been set (in order for static globals to be found).
*/
sym=findglb(name,sGLOBAL);
assert(sym!=NULL);
assert(sym->ident==iFUNCTN || sym->ident==iREFFUNC);
assert(sym->vclass==sGLOBAL);
p=sym->addr;
} /* if */
if (fbin!=NULL) {
write_encoded(fbin,(ucell*)&opcode,1);
write_encoded(fbin,&p,1);
} /* if */
return opcodes(1)+opargs(1);
}
static cell do_jump(FILE *fbin,char *params,cell opcode)
{
int i;
ucell p;
i=(int)hex2long(params,NULL);
assert(i>=0 && i<sc_labnum);
if (fbin!=NULL) {
assert(lbltab!=NULL);
p=lbltab[i];
write_encoded(fbin,(ucell*)&opcode,1);
write_encoded(fbin,&p,1);
} /* if */
return opcodes(1)+opargs(1);
}
static cell do_switch(FILE *fbin,char *params,cell opcode)
{
int i;
ucell p;
i=(int)hex2long(params,NULL);
assert(i>=0 && i<sc_labnum);
if (fbin!=NULL) {
assert(lbltab!=NULL);
p=lbltab[i];
write_encoded(fbin,(ucell*)&opcode,1);
write_encoded(fbin,&p,1);
} /* if */
return opcodes(1)+opargs(1);
}
#if defined __BORLANDC__ || defined __WATCOMC__
#pragma argsused
#endif
static cell do_case(FILE *fbin,char *params,cell opcode)
{
int i;
ucell p,v;
v=hex2long(params,&params);
i=(int)hex2long(params,NULL);
assert(i>=0 && i<sc_labnum);
if (fbin!=NULL) {
assert(lbltab!=NULL);
p=lbltab[i];
write_encoded(fbin,&v,1);
write_encoded(fbin,&p,1);
} /* if */
return opcodes(0)+opargs(2);
}
static OPCODEC opcodelist[] = {
/* node for "invalid instruction" */
{ 0, NULL, 0, noop },
/* opcodes in sorted order */
{ 78, "add", sIN_CSEG, parm0 },
{ 87, "add.c", sIN_CSEG, parm1 },
{ 14, "addr.alt", sIN_CSEG, parm1 },
{ 13, "addr.pri", sIN_CSEG, parm1 },
{ 30, "align.alt", sIN_CSEG, parm1 },
{ 29, "align.pri", sIN_CSEG, parm1 },
{ 81, "and", sIN_CSEG, parm0 },
{121, "bounds", sIN_CSEG, parm1 },
{137, "break", sIN_CSEG, parm0 }, /* version 8 */
{ 49, "call", sIN_CSEG, do_call },
{ 50, "call.pri", sIN_CSEG, parm0 },
{ 0, "case", sIN_CSEG, do_case },
{130, "casetbl", sIN_CSEG, parm0 }, /* version 1 */
{118, "cmps", sIN_CSEG, parm1 },
{ 0, "code", sIN_CSEG, set_currentfile },
{156, "const", sIN_CSEG, parm2 }, /* version 9 */
{ 12, "const.alt", sIN_CSEG, parm1 },
{ 11, "const.pri", sIN_CSEG, parm1 },
{157, "const.s", sIN_CSEG, parm2 }, /* version 9 */
{ 0, "data", sIN_DSEG, set_currentfile },
{114, "dec", sIN_CSEG, parm1 },
{113, "dec.alt", sIN_CSEG, parm0 },
{116, "dec.i", sIN_CSEG, parm0 },
{112, "dec.pri", sIN_CSEG, parm0 },
{115, "dec.s", sIN_CSEG, parm1 },
{ 0, "dump", sIN_DSEG, do_dump },
{ 95, "eq", sIN_CSEG, parm0 },
{106, "eq.c.alt", sIN_CSEG, parm1 },
{105, "eq.c.pri", sIN_CSEG, parm1 },
/*{124, "file", sIN_CSEG, do_file }, */
{119, "fill", sIN_CSEG, parm1 },
{162, "genarray", sIN_CSEG, parm1 },
{163, "genarray.z", sIN_CSEG, parm1 },
{100, "geq", sIN_CSEG, parm0 },
{ 99, "grtr", sIN_CSEG, parm0 },
{120, "halt", sIN_CSEG, parm1 },
{ 45, "heap", sIN_CSEG, parm1 },
{ 27, "idxaddr", sIN_CSEG, parm0 },
{ 28, "idxaddr.b", sIN_CSEG, parm1 },
{109, "inc", sIN_CSEG, parm1 },
{108, "inc.alt", sIN_CSEG, parm0 },
{111, "inc.i", sIN_CSEG, parm0 },
{107, "inc.pri", sIN_CSEG, parm0 },
{110, "inc.s", sIN_CSEG, parm1 },
{ 86, "invert", sIN_CSEG, parm0 },
{ 55, "jeq", sIN_CSEG, do_jump },
{ 60, "jgeq", sIN_CSEG, do_jump },
{ 59, "jgrtr", sIN_CSEG, do_jump },
{ 58, "jleq", sIN_CSEG, do_jump },
{ 57, "jless", sIN_CSEG, do_jump },
{ 56, "jneq", sIN_CSEG, do_jump },
{ 54, "jnz", sIN_CSEG, do_jump },
{ 52, "jrel", sIN_CSEG, parm1 }, /* always a number */
{ 64, "jsgeq", sIN_CSEG, do_jump },
{ 63, "jsgrtr", sIN_CSEG, do_jump },
{ 62, "jsleq", sIN_CSEG, do_jump },
{ 61, "jsless", sIN_CSEG, do_jump },
{ 51, "jump", sIN_CSEG, do_jump },
{128, "jump.pri", sIN_CSEG, parm0 }, /* version 1 */
{ 53, "jzer", sIN_CSEG, do_jump },
{ 31, "lctrl", sIN_CSEG, parm1 },
{ 98, "leq", sIN_CSEG, parm0 },
{ 97, "less", sIN_CSEG, parm0 },
{ 25, "lidx", sIN_CSEG, parm0 },
{ 26, "lidx.b", sIN_CSEG, parm1 },
/*{125, "line", sIN_CSEG, parm2 }, */
{ 2, "load.alt", sIN_CSEG, parm1 },
{154, "load.both", sIN_CSEG, parm2 }, /* version 9 */
{ 9, "load.i", sIN_CSEG, parm0 },
{ 1, "load.pri", sIN_CSEG, parm1 },
{ 4, "load.s.alt", sIN_CSEG, parm1 },
{155, "load.s.both",sIN_CSEG, parm2 }, /* version 9 */
{ 3, "load.s.pri", sIN_CSEG, parm1 },
{ 10, "lodb.i", sIN_CSEG, parm1 },
{ 6, "lref.alt", sIN_CSEG, parm1 },
{ 5, "lref.pri", sIN_CSEG, parm1 },
{ 8, "lref.s.alt", sIN_CSEG, parm1 },
{ 7, "lref.s.pri", sIN_CSEG, parm1 },
{ 34, "move.alt", sIN_CSEG, parm0 },
{ 33, "move.pri", sIN_CSEG, parm0 },
{117, "movs", sIN_CSEG, parm1 },
{ 85, "neg", sIN_CSEG, parm0 },
{ 96, "neq", sIN_CSEG, parm0 },
{134, "nop", sIN_CSEG, parm0 }, /* version 6 */
{ 84, "not", sIN_CSEG, parm0 },
{ 82, "or", sIN_CSEG, parm0 },
{ 43, "pop.alt", sIN_CSEG, parm0 },
{ 42, "pop.pri", sIN_CSEG, parm0 },
{ 46, "proc", sIN_CSEG, parm0 },
{ 40, "push", sIN_CSEG, parm1 },
{133, "push.adr", sIN_CSEG, parm1 }, /* version 4 */
{ 37, "push.alt", sIN_CSEG, parm0 },
{ 39, "push.c", sIN_CSEG, parm1 },
{ 36, "push.pri", sIN_CSEG, parm0 },
{ 38, "push.r", sIN_CSEG, parm1 }, /* obsolete (never generated) */
{ 41, "push.s", sIN_CSEG, parm1 },
{139, "push2", sIN_CSEG, parm2 }, /* version 9 */
{141, "push2.adr", sIN_CSEG, parm2 }, /* version 9 */
{138, "push2.c", sIN_CSEG, parm2 }, /* version 9 */
{140, "push2.s", sIN_CSEG, parm2 }, /* version 9 */
{143, "push3", sIN_CSEG, parm3 }, /* version 9 */
{145, "push3.adr", sIN_CSEG, parm3 }, /* version 9 */
{142, "push3.c", sIN_CSEG, parm3 }, /* version 9 */
{144, "push3.s", sIN_CSEG, parm3 }, /* version 9 */
{147, "push4", sIN_CSEG, parm4 }, /* version 9 */
{149, "push4.adr", sIN_CSEG, parm4 }, /* version 9 */
{146, "push4.c", sIN_CSEG, parm4 }, /* version 9 */
{148, "push4.s", sIN_CSEG, parm4 }, /* version 9 */
{151, "push5", sIN_CSEG, parm5 }, /* version 9 */
{153, "push5.adr", sIN_CSEG, parm5 }, /* version 9 */
{150, "push5.c", sIN_CSEG, parm5 }, /* version 9 */
{152, "push5.s", sIN_CSEG, parm5 }, /* version 9 */
{ 47, "ret", sIN_CSEG, parm0 },
{ 48, "retn", sIN_CSEG, parm0 },
{ 32, "sctrl", sIN_CSEG, parm1 },
{ 73, "sdiv", sIN_CSEG, parm0 },
{ 74, "sdiv.alt", sIN_CSEG, parm0 },
{104, "sgeq", sIN_CSEG, parm0 },
{103, "sgrtr", sIN_CSEG, parm0 },
{ 65, "shl", sIN_CSEG, parm0 },
{ 69, "shl.c.alt", sIN_CSEG, parm1 },
{ 68, "shl.c.pri", sIN_CSEG, parm1 },
{ 66, "shr", sIN_CSEG, parm0 },
{ 71, "shr.c.alt", sIN_CSEG, parm1 },
{ 70, "shr.c.pri", sIN_CSEG, parm1 },
{ 94, "sign.alt", sIN_CSEG, parm0 },
{ 93, "sign.pri", sIN_CSEG, parm0 },
{102, "sleq", sIN_CSEG, parm0 },
{101, "sless", sIN_CSEG, parm0 },
{ 72, "smul", sIN_CSEG, parm0 },
{ 88, "smul.c", sIN_CSEG, parm1 },
/*{127, "srange", sIN_CSEG, parm2 }, -- version 1 */
{ 20, "sref.alt", sIN_CSEG, parm1 },
{ 19, "sref.pri", sIN_CSEG, parm1 },
{ 22, "sref.s.alt", sIN_CSEG, parm1 },
{ 21, "sref.s.pri", sIN_CSEG, parm1 },
{ 67, "sshr", sIN_CSEG, parm0 },
{ 44, "stack", sIN_CSEG, parm1 },
{165, "stackadjust",sIN_CSEG, parm1 },
{ 0, "stksize", 0, noop },
{ 16, "stor.alt", sIN_CSEG, parm1 },
{ 23, "stor.i", sIN_CSEG, parm0 },
{ 15, "stor.pri", sIN_CSEG, parm1 },
{ 18, "stor.s.alt", sIN_CSEG, parm1 },
{ 17, "stor.s.pri", sIN_CSEG, parm1 },
{164, "stradjust.pri", sIN_CSEG, parm0 },
{ 24, "strb.i", sIN_CSEG, parm1 },
{ 79, "sub", sIN_CSEG, parm0 },
{ 80, "sub.alt", sIN_CSEG, parm0 },
{132, "swap.alt", sIN_CSEG, parm0 }, /* version 4 */
{131, "swap.pri", sIN_CSEG, parm0 }, /* version 4 */
{129, "switch", sIN_CSEG, do_switch }, /* version 1 */
/*{126, "symbol", sIN_CSEG, do_symbol }, */
/*{136, "symtag", sIN_CSEG, parm1 }, -- version 7 */
{123, "sysreq.c", sIN_CSEG, parm1 },
{135, "sysreq.n", sIN_CSEG, parm2 }, /* version 9 (replaces SYSREQ.d from earlier version) */
{122, "sysreq.pri", sIN_CSEG, parm0 },
{161, "tracker.pop.setheap", sIN_CSEG, parm0 },
{160, "tracker.push.c", sIN_CSEG, parm1 },
{ 76, "udiv", sIN_CSEG, parm0 },
{ 77, "udiv.alt", sIN_CSEG, parm0 },
{ 75, "umul", sIN_CSEG, parm0 },
{ 35, "xchg", sIN_CSEG, parm0 },
{ 83, "xor", sIN_CSEG, parm0 },
{ 91, "zero", sIN_CSEG, parm1 },
{ 90, "zero.alt", sIN_CSEG, parm0 },
{ 89, "zero.pri", sIN_CSEG, parm0 },
{ 92, "zero.s", sIN_CSEG, parm1 },
};
#define MAX_INSTR_LEN 30
static int findopcode(char *instr,int maxlen)
{
int low,high,mid,cmp;
char str[MAX_INSTR_LEN];
if (maxlen>=MAX_INSTR_LEN)
return 0;
strlcpy(str,instr,maxlen+1);
/* look up the instruction with a binary search
* the assembler is case insensitive to instructions (but case sensitive
* to symbols)
*/
low=1; /* entry 0 is reserved (for "not found") */
high=(sizeof opcodelist / sizeof opcodelist[0])-1;
while (low<high) {
mid=(low+high)/2;
assert(opcodelist[mid].name!=NULL);
cmp=stricmp(str,opcodelist[mid].name);
if (cmp>0)
low=mid+1;
else
high=mid;
} /* while */
assert(low==high);
if (stricmp(str,opcodelist[low].name)==0)
return low; /* found */
return 0; /* not found, return special index */
}
SC_FUNC int assemble(FILE *fout,FILE *fin)
{
AMX_HEADER hdr;
AMX_FUNCSTUBNT func;
int numpublics,numnatives,numlibraries,numpubvars,numtags,padding;
long nametablesize,nameofs;
#if PAWN_CELL_SIZE > 32
char line[512];
#else
char line[256];
#endif
char *instr,*params;
int i,pass,size;
int16_t count;
symbol *sym, **nativelist;
constvalue *constptr;
cell mainaddr;
char nullchar;
char testalias[sNAMEMAX+1];
/* if compression failed, restart the assembly with compaction switched off */
if (setjmp(compact_err)!=0) {
assert(sc_compress); /* cannot arrive here if compact encoding was disabled */
sc_compress=FALSE;
pc_resetbin(fout,0);
error(232); /* disabled compact encoding */
} /* if */
#if !defined NDEBUG
/* verify that the opcode list is sorted (skip entry 1; it is reserved
* for a non-existant opcode)
*/
assert(opcodelist[1].name!=NULL);
for (i=2; i<(sizeof opcodelist / sizeof opcodelist[0]); i++) {
assert(opcodelist[i].name!=NULL);
assert(stricmp(opcodelist[i].name,opcodelist[i-1].name)>0);
} /* for */
#endif
writeerror=FALSE;
nametablesize=sizeof(int16_t);
numpublics=0;
numnatives=0;
numpubvars=0;
mainaddr=-1;
/* count number of public and native functions and public variables */
for (sym=glbtab.next; sym!=NULL; sym=sym->next) {
int match=0;
if (sym->ident==iFUNCTN) {
if ((sym->usage & uNATIVE)!=0 && (sym->usage & uREAD)!=0 && sym->addr>=0) {
match=++numnatives;
}
if ((sym->usage & uPUBLIC)!=0 && (sym->usage & uDEFINE)!=0)
match=++numpublics;
if (strcmp(sym->name,uMAINFUNC)==0) {
assert(sym->vclass==sGLOBAL);
mainaddr=sym->addr;
} /* if */
} else if (sym->ident==iVARIABLE || sym->ident == iARRAY || sym->ident == iREFARRAY) {
if ((sym->usage & uPUBLIC)!=0 && (sym->usage & (uREAD | uWRITTEN))!=0)
match=++numpubvars;
} /* if */
if (match) {
const char *aliasptr = sym->name;
assert(sym!=NULL);
if (((sym->usage & uNATIVE)!=0) && lookup_alias(testalias,sym->name)) {
aliasptr = "@";
} /* if */
nametablesize+=strlen(aliasptr)+1;
} /* if */
} /* for */
assert(numnatives==ntv_funcid);
/* count number of libraries */
numlibraries=0;
if (pc_addlibtable) {
for (constptr=libname_tab.next; constptr!=NULL; constptr=constptr->next) {
if (constptr->value>0) {
assert(strlen(constptr->name)>0);
numlibraries++;
nametablesize+=strlen(constptr->name)+1;
} /* if */
} /* for */
} /* if */
/* count number of public tags */
numtags=0;
for (constptr=tagname_tab.next; constptr!=NULL; constptr=constptr->next) {
/*if ((constptr->value & PUBLICTAG)!=0) {*/
assert(strlen(constptr->name)>0);
numtags++;
nametablesize+=strlen(constptr->name)+1;
/*} if */
} /* for */
/* pad the header to sc_dataalign
* => thereby the code segment is aligned
* => since the code segment is padded to a sc_dataalign boundary, the data segment is aligned
* => and thereby the stack top is aligned too
*/
assert(sc_dataalign!=0);
padding= (int)(sc_dataalign - (sizeof hdr + nametablesize) % sc_dataalign);
if (padding==sc_dataalign)
padding=0;
/* write the abstract machine header */
memset(&hdr, 0, sizeof hdr);
hdr.magic=(unsigned short)AMX_MAGIC;
hdr.file_version=(char)((pc_optimize<=sOPTIMIZE_NOMACRO) ? MAX_FILE_VER_JIT : CUR_FILE_VERSION);
hdr.amx_version=(char)((pc_optimize<=sOPTIMIZE_NOMACRO) ? MIN_AMX_VER_JIT : MIN_AMX_VERSION);
hdr.flags=(short)(sc_debug & sSYMBOLIC);
if (sc_compress)
hdr.flags|=AMX_FLAG_COMPACT;
if (sc_debug==0)
hdr.flags|=AMX_FLAG_NOCHECKS;
if (pc_memflags & suSLEEP_INSTR)
hdr.flags|=AMX_FLAG_SLEEP;
hdr.defsize=sizeof(AMX_FUNCSTUBNT);
hdr.publics=sizeof hdr; /* public table starts right after the header */
hdr.natives=hdr.publics + numpublics*sizeof(AMX_FUNCSTUBNT);
hdr.libraries=hdr.natives + numnatives*sizeof(AMX_FUNCSTUBNT);
hdr.pubvars=hdr.libraries + numlibraries*sizeof(AMX_FUNCSTUBNT);
hdr.tags=hdr.pubvars + numpubvars*sizeof(AMX_FUNCSTUBNT);
hdr.nametable=hdr.tags + numtags*sizeof(AMX_FUNCSTUBNT);
hdr.cod=hdr.nametable + nametablesize + padding;
hdr.dat=hdr.cod + code_idx;
hdr.hea=hdr.dat + glb_declared*sizeof(cell);
hdr.stp=hdr.hea + pc_stksize*sizeof(cell);
hdr.cip=mainaddr;
hdr.size=hdr.hea; /* preset, this is incorrect in case of compressed output */
pc_writebin(fout,&hdr,sizeof hdr);
/* dump zeros up to the rest of the header, so that we can easily "seek" */
nullchar='\0';
for (nameofs=sizeof hdr; nameofs<hdr.cod; nameofs++)
pc_writebin(fout,&nullchar,1);
nameofs=hdr.nametable+sizeof(int16_t);
/* write the public functions table */
count=0;
for (sym=glbtab.next; sym!=NULL; sym=sym->next) {
if (sym->ident==iFUNCTN
&& (sym->usage & uPUBLIC)!=0 && (sym->usage & uDEFINE)!=0)
{
assert(sym->vclass==sGLOBAL);
func.address=sym->addr;
func.nameofs=nameofs;
#if BYTE_ORDER==BIG_ENDIAN
align32(&func.address);
align32(&func.nameofs);
#endif
pc_resetbin(fout,hdr.publics+count*sizeof(AMX_FUNCSTUBNT));
pc_writebin(fout,&func,sizeof func);
pc_resetbin(fout,nameofs);
pc_writebin(fout,sym->name,strlen(sym->name)+1);
nameofs+=strlen(sym->name)+1;
count++;
} /* if */
} /* for */
/* write the natives table */
/* The native functions must be written in sorted order. (They are
* sorted on their "id", not on their name). A nested loop to find
* each successive function would be an O(n^2) operation. But we
* do not really need to sort, because the native function id's
* are sequential and there are no duplicates. So we first walk
* through the complete symbol list and store a pointer to every
* native function of interest in a temporary table, where its id
* serves as the index in the table. Now we can walk the table and
* have all native functions in sorted order.
*/
if (numnatives>0) {
nativelist=(symbol **)malloc(numnatives*sizeof(symbol *));
if (nativelist==NULL)
error(103); /* insufficient memory */
#if !defined NDEBUG
memset(nativelist,0,numnatives*sizeof(symbol *)); /* for NULL checking */
#endif
for (sym=glbtab.next; sym!=NULL; sym=sym->next) {
if (sym->ident==iFUNCTN && (sym->usage & uNATIVE)!=0 && (sym->usage & uREAD)!=0 && sym->addr>=0) {
assert(sym->addr < numnatives);
nativelist[(int)sym->addr]=sym;
} /* if */
} /* for */
count=0;
sp_fdbg_ntv_start(numnatives);
for (i=0; i<numnatives; i++) {
const char *aliasptr;
sym=nativelist[i];
sp_fdbg_ntv_hook(i, sym);
assert(sym!=NULL);
aliasptr = sym->name;
if (lookup_alias(testalias,sym->name)) {
aliasptr = "@";
}
assert(sym->vclass==sGLOBAL);
func.address=0;
func.nameofs=nameofs;
#if BYTE_ORDER==BIG_ENDIAN
align32(&func.address);
align32(&func.nameofs);
#endif
pc_resetbin(fout,hdr.natives+count*sizeof(AMX_FUNCSTUBNT));
pc_writebin(fout,&func,sizeof func);
pc_resetbin(fout,nameofs);
pc_writebin(fout,(void *)aliasptr,strlen(aliasptr)+1);
nameofs+=strlen(aliasptr)+1;
count++;
} /* for */
free(nativelist);
} /* if */
/* write the libraries table */
if (pc_addlibtable) {
count=0;
for (constptr=libname_tab.next; constptr!=NULL; constptr=constptr->next) {
if (constptr->value>0) {
assert(strlen(constptr->name)>0);
func.address=0;
func.nameofs=nameofs;
#if BYTE_ORDER==BIG_ENDIAN
align32(&func.address);
align32(&func.nameofs);
#endif
pc_resetbin(fout,hdr.libraries+count*sizeof(AMX_FUNCSTUBNT));
pc_writebin(fout,&func,sizeof func);
pc_resetbin(fout,nameofs);
pc_writebin(fout,constptr->name,strlen(constptr->name)+1);
nameofs+=strlen(constptr->name)+1;
count++;
} /* if */
} /* for */
} /* if */
/* write the public variables table */
count=0;
for (sym=glbtab.next; sym!=NULL; sym=sym->next) {
if ((sym->ident==iVARIABLE || sym->ident==iARRAY || sym->ident==iREFARRAY)
&& (sym->usage & uPUBLIC)!=0 && (sym->usage & (uREAD | uWRITTEN))!=0) {
//removed until structs don't seem to mess this up
//assert((sym->usage & uDEFINE)!=0);
assert(sym->vclass==sGLOBAL);
func.address=sym->addr;
func.nameofs=nameofs;
#if BYTE_ORDER==BIG_ENDIAN
align32(&func.address);
align32(&func.nameofs);
#endif
pc_resetbin(fout,hdr.pubvars+count*sizeof(AMX_FUNCSTUBNT));
pc_writebin(fout,&func,sizeof func);
pc_resetbin(fout,nameofs);
pc_writebin(fout,sym->name,strlen(sym->name)+1);
nameofs+=strlen(sym->name)+1;
count++;
} /* if */
} /* for */
/* write the public tagnames table */
count=0;
for (constptr=tagname_tab.next; constptr!=NULL; constptr=constptr->next) {
/*if ((constptr->value & PUBLICTAG)!=0) {*/
assert(strlen(constptr->name)>0);
func.address=constptr->value & TAGMASK;
func.nameofs=nameofs;
#if BYTE_ORDER==BIG_ENDIAN
align32(&func.address);
align32(&func.nameofs);
#endif
pc_resetbin(fout,hdr.tags+count*sizeof(AMX_FUNCSTUBNT));
pc_writebin(fout,&func,sizeof func);
pc_resetbin(fout,nameofs);
pc_writebin(fout,constptr->name,strlen(constptr->name)+1);
nameofs+=strlen(constptr->name)+1;
count++;
/*} if */
} /* for */
/* write the "maximum name length" field in the name table */
assert(nameofs==hdr.nametable+nametablesize);
pc_resetbin(fout,hdr.nametable);
count=sNAMEMAX;
#if BYTE_ORDER==BIG_ENDIAN
align16(&count);
#endif
pc_writebin(fout,&count,sizeof count);
pc_resetbin(fout,hdr.cod);
/* First pass: relocate all labels */
/* This pass is necessary because the code addresses of labels is only known
* after the peephole optimization flag. Labels can occur inside expressions
* (e.g. the conditional operator), which are optimized.
*/
lbltab=NULL;
if (sc_labnum>0) {
/* only very short programs have zero labels; no first pass is needed
* if there are no labels */
lbltab=(cell *)malloc(sc_labnum*sizeof(cell));
if (lbltab==NULL)
error(103); /* insufficient memory */
codeindex=0;
pc_resetasm(fin);
while (pc_readasm(fin,line,sizeof line)!=NULL) {
stripcomment(line);
instr=skipwhitespace(line);
/* ignore empty lines */
if (*instr=='\0')
continue;
if (tolower(*instr)=='l' && *(instr+1)=='.') {
int lindex=(int)hex2long(instr+2,NULL);
assert(lindex>=0 && lindex<sc_labnum);
lbltab[lindex]=codeindex;
} else {
/* get to the end of the instruction (make use of the '\n' that fgets()
* added at the end of the line; this way we will *always* drop on a
* whitespace character) */
for (params=instr; *params!='\0' && !isspace(*params); params++)
/* nothing */;
assert(params>instr);
i=findopcode(instr,(int)(params-instr));
if (opcodelist[i].name==NULL) {
*params='\0';
error(104,instr); /* invalid assembler instruction */
} /* if */
if (opcodelist[i].segment==sIN_CSEG)
codeindex+=opcodelist[i].func(NULL,skipwhitespace(params),opcodelist[i].opcode);
} /* if */
} /* while */
} /* if */
/* Second pass (actually 2 more passes, one for all code and one for all data) */
bytes_in=0;
bytes_out=0;
for (pass=sIN_CSEG; pass<=sIN_DSEG; pass++) {
pc_resetasm(fin);
while (pc_readasm(fin,line,sizeof line)!=NULL) {
stripcomment(line);
instr=skipwhitespace(line);
/* ignore empty lines and labels (labels have a special syntax, so these
* must be parsed separately) */
if (*instr=='\0' || tolower(*instr)=='l' && *(instr+1)=='.')
continue;
/* get to the end of the instruction (make use of the '\n' that fgets()
* added at the end of the line; this way we will *always* drop on a
* whitespace character) */
for (params=instr; *params!='\0' && !isspace(*params); params++)
/* nothing */;
assert(params>instr);
i=findopcode(instr,(int)(params-instr));
assert(opcodelist[i].name!=NULL);
if (opcodelist[i].segment==pass)
opcodelist[i].func(fout,skipwhitespace(params),opcodelist[i].opcode);
} /* while */
} /* for */
if (bytes_out-bytes_in>0)
error(106); /* compression buffer overflow */
if (lbltab!=NULL) {
free(lbltab);
#if !defined NDEBUG
lbltab=NULL;
#endif
} /* if */
if (sc_compress)
hdr.size=pc_lengthbin(fout);/* get this value before appending debug info */
if (!writeerror && (sc_debug & sSYMBOLIC)!=0)
append_dbginfo(fout); /* optionally append debug file */
if (writeerror)
error(101,"disk full");
/* adjust the header */
size=(int)hdr.cod; /* save, the value in the header may be swapped */
#if BYTE_ORDER==BIG_ENDIAN
align32(&hdr.size);
align16(&hdr.magic);
align16(&hdr.flags);
align16(&hdr.defsize);
align32(&hdr.publics);
align32(&hdr.natives);
align32(&hdr.libraries);
align32(&hdr.pubvars);
align32(&hdr.tags);
align32(&hdr.nametable);
align32(&hdr.cod);
align32(&hdr.dat);
align32(&hdr.hea);
align32(&hdr.stp);
align32(&hdr.cip);
#endif
pc_resetbin(fout,0);
pc_writebin(fout,&hdr,sizeof hdr);
/* return the size of the header (including name tables, but excluding code
* or data sections)
*/
return size;
}
static void append_dbginfo(FILE *fout)
{
AMX_DBG_HDR dbghdr;
AMX_DBG_LINE dbgline;
AMX_DBG_SYMBOL dbgsym;
AMX_DBG_SYMDIM dbgidxtag[sDIMEN_MAX];
int index,dim,dbgsymdim;
char *str,*prevstr,*name,*prevname;
ucell codeidx,previdx;
constvalue *constptr;
char symname[2*sNAMEMAX+16];
int16_t id1,id2;
ucell address;
/* header with general information */
memset(&dbghdr, 0, sizeof dbghdr);
dbghdr.size=sizeof dbghdr;
dbghdr.magic=AMX_DBG_MAGIC;
dbghdr.file_version=CUR_FILE_VERSION;
dbghdr.amx_version=MIN_AMX_VERSION;
/* first pass: collect the number of items in various tables */
/* file table */
previdx=0;
prevstr=NULL;
prevname=NULL;
for (index=0; (str=get_dbgstring(index))!=NULL; index++) {
assert(str!=NULL);
assert(str[0]!='\0' && str[1]==':');
if (str[0]=='F') {
codeidx=hex2long(str+2,&name);
if (codeidx!=previdx) {
if (prevstr!=NULL) {
assert(prevname!=NULL);
dbghdr.files++;
dbghdr.size+=sizeof(cell)+strlen(prevname)+1;
} /* if */
previdx=codeidx;
} /* if */
prevstr=str;
prevname=skipwhitespace(name);
} /* if */
} /* for */
if (prevstr!=NULL) {
assert(prevname!=NULL);
dbghdr.files++;
dbghdr.size+=sizeof(cell)+strlen(prevname)+1;
} /* if */
/* line number table */
for (index=0; (str=get_dbgstring(index))!=NULL; index++) {
assert(str!=NULL);
assert(str[0]!='\0' && str[1]==':');
if (str[0]=='L') {
dbghdr.lines++;
dbghdr.size+=sizeof(AMX_DBG_LINE);
} /* if */
} /* for */
/* symbol table */
for (index=0; (str=get_dbgstring(index))!=NULL; index++) {
assert(str!=NULL);
assert(str[0]!='\0' && str[1]==':');
if (str[0]=='S') {
dbghdr.symbols++;
name=strchr(str+2,':');
assert(name!=NULL);
dbghdr.size+=sizeof(AMX_DBG_SYMBOL)+strlen(skipwhitespace(name+1));
if ((prevstr=strchr(name,'['))!=NULL)
while ((prevstr=strchr(prevstr+1,':'))!=NULL)
dbghdr.size+=sizeof(AMX_DBG_SYMDIM);
} /* if */
} /* for */
/* tag table */
for (constptr=tagname_tab.next; constptr!=NULL; constptr=constptr->next) {
assert(strlen(constptr->name)>0);
dbghdr.tags++;
dbghdr.size+=sizeof(AMX_DBG_TAG)+strlen(constptr->name);
} /* for */
/* automaton table */
for (constptr=sc_automaton_tab.next; constptr!=NULL; constptr=constptr->next) {
assert(constptr->index==0 && strlen(constptr->name)==0 || strlen(constptr->name)>0);
dbghdr.automatons++;
dbghdr.size+=sizeof(AMX_DBG_MACHINE)+strlen(constptr->name);
} /* for */
/* state table */
for (constptr=sc_state_tab.next; constptr!=NULL; constptr=constptr->next) {
assert(strlen(constptr->name)>0);
dbghdr.states++;
dbghdr.size+=sizeof(AMX_DBG_STATE)+strlen(constptr->name);
} /* for */
/* pass 2: generate the tables */
#if BYTE_ORDER==BIG_ENDIAN
align32((uint32_t*)&dbghdr.size);
align16(&dbghdr.magic);
align16(&dbghdr.flags);
align16(&dbghdr.files);
align16(&dbghdr.lines);
align16(&dbghdr.symbols);
align16(&dbghdr.tags);
align16(&dbghdr.automatons);
align16(&dbghdr.states);
#endif
writeerror |= !pc_writebin(fout,&dbghdr,sizeof dbghdr);
/* file table */
previdx=0;
prevstr=NULL;
prevname=NULL;
for (index=0; (str=get_dbgstring(index))!=NULL; index++) {
assert(str!=NULL);
assert(str[0]!='\0' && str[1]==':');
if (str[0]=='F') {
codeidx=hex2long(str+2,&name);
if (codeidx!=previdx) {
if (prevstr!=NULL) {
assert(prevname!=NULL);
#if BYTE_ORDER==BIG_ENDIAN
aligncell(&previdx);
#endif
writeerror |= !pc_writebin(fout,&previdx,sizeof previdx);
writeerror |= !pc_writebin(fout,prevname,strlen(prevname)+1);
} /* if */
previdx=codeidx;
} /* if */
prevstr=str;
prevname=skipwhitespace(name);
} /* if */
} /* for */
if (prevstr!=NULL) {
assert(prevname!=NULL);
#if BYTE_ORDER==BIG_ENDIAN
aligncell(&previdx);
#endif
writeerror |= !pc_writebin(fout,&previdx,sizeof previdx);
writeerror |= !pc_writebin(fout,prevname,strlen(prevname)+1);
} /* if */
/* line number table */
for (index=0; (str=get_dbgstring(index))!=NULL; index++) {
assert(str!=NULL);
assert(str[0]!='\0' && str[1]==':');
if (str[0]=='L') {
dbgline.address=hex2long(str+2,&str);
dbgline.line=(int32_t)hex2long(str,NULL);
#if BYTE_ORDER==BIG_ENDIAN
aligncell(&dbgline.address);
align32(&dbgline.line);
#endif
writeerror |= !pc_writebin(fout,&dbgline,sizeof dbgline);
} /* if */
} /* for */
/* symbol table */
for (index=0; (str=get_dbgstring(index))!=NULL; index++) {
assert(str!=NULL);
assert(str[0]!='\0' && str[1]==':');
if (str[0]=='S') {
dbgsym.address=hex2long(str+2,&str);
dbgsym.tag=(int16_t)hex2long(str,&str);
str=skipwhitespace(str);
assert(*str==':');
name=skipwhitespace(str+1);
str=strchr(name,' ');
assert(str!=NULL);
assert((int)(str-name)<sizeof symname);
strlcpy(symname,name,(int)(str-name)+1);
dbgsym.codestart=hex2long(str,&str);
dbgsym.codeend=hex2long(str,&str);
dbgsym.ident=(char)hex2long(str,&str);
dbgsym.vclass=(char)hex2long(str,&str);
dbgsym.dim=0;
str=skipwhitespace(str);
if (*str=='[') {
while (*(str=skipwhitespace(str+1))!=']') {
dbgidxtag[dbgsym.dim].tag=(int16_t)hex2long(str,&str);
str=skipwhitespace(str);
assert(*str==':');
dbgidxtag[dbgsym.dim].size=hex2long(str+1,&str);
dbgsym.dim++;
} /* while */
} /* if */
dbgsymdim = dbgsym.dim;
#if BYTE_ORDER==BIG_ENDIAN
aligncell(&dbgsym.address);
align16(&dbgsym.tag);
aligncell(&dbgsym.codestart);
aligncell(&dbgsym.codeend);
align16(&dbgsym.dim);
#endif
writeerror |= !pc_writebin(fout,&dbgsym,offsetof(AMX_DBG_SYMBOL, name));
writeerror |= !pc_writebin(fout,symname,strlen(symname)+1);
for (dim=0; dim<dbgsymdim; dim++) {
#if BYTE_ORDER==BIG_ENDIAN
align16(&dbgidxtag[dim].tag);
aligncell(&dbgidxtag[dim].size);
#endif
writeerror |= !pc_writebin(fout,&dbgidxtag[dim],sizeof dbgidxtag[dim]);
} /* for */
} /* if */
} /* for */
/* tag table */
for (constptr=tagname_tab.next; constptr!=NULL; constptr=constptr->next) {
assert(strlen(constptr->name)>0);
id1=(int16_t)(constptr->value & TAGMASK);
#if BYTE_ORDER==BIG_ENDIAN
align16(&id1);
#endif
writeerror |= !pc_writebin(fout,&id1,sizeof id1);
writeerror |= !pc_writebin(fout,constptr->name,strlen(constptr->name)+1);
} /* for */
/* automaton table */
for (constptr=sc_automaton_tab.next; constptr!=NULL; constptr=constptr->next) {
assert(constptr->index==0 && strlen(constptr->name)==0 || strlen(constptr->name)>0);
id1=(int16_t)constptr->index;
address=(ucell)constptr->value;
#if BYTE_ORDER==BIG_ENDIAN
align16(&id1);
aligncell(&address);
#endif
writeerror |= !pc_writebin(fout,&id1,sizeof id1);
writeerror |= !pc_writebin(fout,&address,sizeof address);
writeerror |= !pc_writebin(fout,constptr->name,strlen(constptr->name)+1);
} /* for */
/* state table */
for (constptr=sc_state_tab.next; constptr!=NULL; constptr=constptr->next) {
assert(strlen(constptr->name)>0);
id1=(int16_t)constptr->value;
id2=(int16_t)constptr->index;
address=(ucell)constptr->value;
#if BYTE_ORDER==BIG_ENDIAN
align16(&id1);
align16(&id2);
#endif
writeerror |= !pc_writebin(fout,&id1,sizeof id1);
writeerror |= !pc_writebin(fout,&id2,sizeof id2);
writeerror |= !pc_writebin(fout,constptr->name,strlen(constptr->name)+1);
} /* for */
delete_dbgstringtable();
}
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