qzdoom/src/zscript/vmdisasm.cpp

#include "vm.h"
#include "c_console.h"

#define NOP		MODE_AUNUSED | MODE_BUNUSED | MODE_CUNUSED

#define LI		MODE_AI | MODE_BCJOINT | MODE_BCIMMS
#define LKI		MODE_AI | MODE_BCJOINT | MODE_BCKI
#define LKF		MODE_AF | MODE_BCJOINT | MODE_BCKF
#define LKS		MODE_AS | MODE_BCJOINT | MODE_BCKS
#define LKP		MODE_AP | MODE_BCJOINT | MODE_BCKP
#define LFP		MODE_AP | MODE_BUNUSED | MODE_CUNUSED

#define RIRPKI	MODE_AI | MODE_BP | MODE_CKI
#define RIRPRI	MODE_AI | MODE_BP | MODE_CI
#define RFRPKI	MODE_AF | MODE_BP | MODE_CKI
#define RFRPRI	MODE_AF | MODE_BP | MODE_CI
#define RSRPKI	MODE_AS | MODE_BP | MODE_CKI
#define RSRPRI	MODE_AS | MODE_BP | MODE_CI
#define RPRPKI	MODE_AP | MODE_BP | MODE_CKI
#define RPRPRI	MODE_AP | MODE_BP | MODE_CI
#define RVRPKI	MODE_AV | MODE_BP | MODE_CKI
#define RVRPRI	MODE_AV | MODE_BP | MODE_CI
#define RIRPI8	MODE_AI | MODE_BP | MODE_CIMMZ

#define RPRIKI	MODE_AP | MODE_BI | MODE_CKI
#define RPRIRI	MODE_AP | MODE_BI | MODE_CI
#define RPRFKI	MODE_AP | MODE_BF | MODE_CKI
#define RPRFRI	MODE_AP | MODE_BF | MODE_CI
#define RPRSKI	MODE_AP | MODE_BS | MODE_CKI
#define RPRSRI	MODE_AP | MODE_BS | MODE_CI
#define RPRPKI	MODE_AP | MODE_BP | MODE_CKI
#define RPRPRI	MODE_AP | MODE_BP | MODE_CI
#define RPRVKI	MODE_AP | MODE_BV | MODE_CKI
#define RPRVRI	MODE_AP | MODE_BV | MODE_CI
#define RPRII8	MODE_AP | MODE_BI | MODE_CIMMZ

#define RIRI	MODE_AI | MODE_BI | MODE_CUNUSED
#define RFRF	MODE_AF | MODE_BF | MODE_CUNUSED
#define	RSRS	MODE_AS | MODE_BS | MODE_CUNUSED
#define RPRP	MODE_AP | MODE_BP | MODE_CUNUSED
#define RXRXI8	MODE_AX | MODE_BX | MODE_CIMMZ
#define RPRPRP	MODE_AP | MODE_BP | MODE_CP
#define RPRPKP	MODE_AP | MODE_BP | MODE_CKP

#define RII16	MODE_AI | MODE_BCJOINT | MODE_BCIMMS
#define I24		MODE_ABCJOINT
#define I8		MODE_AIMMZ | MODE_BUNUSED | MODE_CUNUSED
#define I8I16	MODE_AIMMZ | MODE_BCIMMZ
#define __BCP	MODE_AUNUSED | MODE_BCJOINT | MODE_BCPARAM
#define RPI8	MODE_AP | MODE_BIMMZ | MODE_CUNUSED
#define KPI8	MODE_AKP | MODE_BIMMZ | MODE_CUNUSED
#define RPI8I8	MODE_AP | MODE_BIMMZ | MODE_CIMMZ
#define KPI8I8	MODE_AKP | MODE_BIMMZ | MODE_CIMMZ
#define I8BCP	MODE_AIMMZ | MODE_BCJOINT | MODE_BCPARAM
#define THROW	MODE_AIMMZ | MODE_BCTHROW
#define CATCH	MODE_AIMMZ | MODE_BCCATCH
#define CAST	MODE_AX | MODE_BX | MODE_CIMMZ | MODE_BCCAST

#define RSRSRS	MODE_AS | MODE_BS | MODE_CS
#define RIRS	MODE_AI | MODE_BS | MODE_CUNUSED
#define I8RXRX	MODE_AIMMZ | MODE_BX | MODE_CX

#define RIRIRI	MODE_AI | MODE_BI | MODE_CI
#define RIRII8	MODE_AI | MODE_BI | MODE_CIMMZ
#define RIRIKI	MODE_AI | MODE_BI | MODE_CKI
#define RIKIRI	MODE_AI | MODE_BKI | MODE_CI
#define RIKII8	MODE_AI | MODE_BKI | MODE_CIMMZ
#define RIRIIs	MODE_AI | MODE_BI | MODE_CIMMS
#define RIRI	MODE_AI | MODE_BI | MODE_CUNUSED
#define I8RIRI	MODE_AIMMZ | MODE_BI | MODE_CI
#define I8RIKI	MODE_AIMMZ | MODE_BI | MODE_CKI
#define I8KIRI	MODE_AIMMZ | MODE_BKI | MODE_CI

#define RFRFRF	MODE_AF | MODE_BF | MODE_CF
#define RFRFKF	MODE_AF | MODE_BF | MODE_CKF
#define RFKFRF	MODE_AF | MODE_BKF | MODE_CF
#define I8RFRF	MODE_AIMMZ | MODE_BF | MODE_CF
#define I8RFKF	MODE_AIMMZ | MODE_BF | MODE_CKF
#define I8KFRF	MODE_AIMMZ | MODE_BKF | MODE_CF
#define RFRFI8	MODE_AF | MODE_BF | MODE_CIMMZ

#define RVRV	MODE_AV | MODE_BV | MODE_CUNUSED
#define RVRVRV	MODE_AV | MODE_BV | MODE_CV
#define RVRVKV	MODE_AV | MODE_BV | MODE_CKV
#define RVKVRV	MODE_AV | MODE_BKV | MODE_CV
#define RFRV	MODE_AF | MODE_BV | MODE_CUNUSED
#define I8RVRV	MODE_AIMMZ | MODE_BV | MODE_CV
#define I8RVKV	MODE_AIMMZ | MODE_BV | MODE_CKV

#define RPRPRI	MODE_AP | MODE_BP | MODE_CI
#define RPRPKI	MODE_AP | MODE_BP | MODE_CKI
#define RIRPRP	MODE_AI | MODE_BP | MODE_CP
#define I8RPRP	MODE_AIMMZ | MODE_BP | MODE_CP
#define I8RPKP	MODE_AIMMZ | MODE_BP | MODE_CKP

#define CIRR	MODE_ACMP | MODE_BI | MODE_CI
#define CIRK	MODE_ACMP | MODE_BI | MODE_CKI
#define CIKR	MODE_ACMP | MODE_BKI | MODE_CI
#define CFRR	MODE_ACMP | MODE_BF | MODE_CF
#define CFRK	MODE_ACMP | MODE_BF | MODE_CKF
#define CFKR	MODE_ACMP | MODE_BKF | MODE_CF
#define CVRR	MODE_ACMP | MODE_BV | MODE_CV
#define CVRK	MODE_ACMP | MODE_BV | MODE_CKV
#define CPRR	MODE_ACMP | MODE_BP | MODE_CP
#define CPRK	MODE_ACMP | MODE_BP | MODE_CKP

const VMOpInfo OpInfo[NUM_OPS] =
{
#define xx(op, name, mode)	{ #name, mode }
#include "vmops.h"
};

static const char *const FlopNames[] =
{
	"abs",
	"neg",
	"exp",
	"log",
	"log10",
	"sqrt",
	"ceil",
	"floor",

	"acos rad",
	"asin rad",
	"atan rad",
	"cos rad",
	"sin rad",
	"tan rad",

	"acos deg",
	"asin deg",
	"atan deg",
	"cos deg",
	"sin deg",
	"tan deg",

	"cosh",
	"sinh",
	"tanh",
};

static int print_reg(FILE *out, int col, int arg, int mode, int immshift, const VMScriptFunction *func);

static int printf_wrapper(FILE *f, const char *fmt, ...)
{
	va_list argptr;
	int count;

	va_start(argptr, fmt);
	if (f == NULL)
	{
		count = VPrintf(PRINT_HIGH, fmt, argptr);
	}
	else
	{
		count = vfprintf(f, fmt, argptr);
	}
	va_end(argptr);
	return count;
}

void VMDumpConstants(FILE *out, const VMScriptFunction *func)
{
	char tmp[21];
	int i, j, k, kk;

	if (func->KonstD != NULL && func->NumKonstD != 0)
	{
		printf_wrapper(out, "\nConstant integers:\n");
		kk = (func->NumKonstD + 3) / 4;
		for (i = 0; i < kk; ++i)
		{
			for (j = 0, k = i; j < 4 && k < func->NumKonstD; j++, k += kk)
			{
				mysnprintf(tmp, countof(tmp), "%3d. %d", k, func->KonstD[k]);
				printf_wrapper(out, "%-20s", tmp);
			}
			printf_wrapper(out, "\n");
		}
	}
	if (func->KonstF != NULL && func->NumKonstF != 0)
	{
		printf_wrapper(out, "\nConstant floats:\n");
		kk = (func->NumKonstF + 3) / 4;
		for (i = 0; i < kk; ++i)
		{
			for (j = 0, k = i; j < 4 && k < func->NumKonstF; j++, k += kk)
			{
				mysnprintf(tmp, countof(tmp), "%3d. %.16f", k, func->KonstF[k]);
				printf_wrapper(out, "%-20s", tmp);
			}
			printf_wrapper(out, "\n");
		}
	}
	if (func->KonstA != NULL && func->NumKonstA != 0)
	{
		printf_wrapper(out, "\nConstant addresses:\n");
		kk = (func->NumKonstA + 3) / 4;
		for (i = 0; i < kk; ++i)
		{
			for (j = 0, k = i; j < 4 && k < func->NumKonstA; j++, k += kk)
			{
				mysnprintf(tmp, countof(tmp), "%3d. %p:%d", k, func->KonstA[k].v, func->KonstATags()[k]);
				printf_wrapper(out, "%-20s", tmp);
			}
			printf_wrapper(out, "\n");
		}
	}
	if (func->KonstS != NULL && func->NumKonstS != 0)
	{
		printf_wrapper(out, "\nConstant strings:\n");
		for (i = 0; i < func->NumKonstS; ++i)
		{
			printf_wrapper(out, "%3d. %s\n", i, func->KonstS[i].GetChars());
		}
	}
}

void VMDisasm(FILE *out, const VMOP *code, int codesize, const VMScriptFunction *func)
{
	VMFunction *callfunc;
	const char *callname;
	const char *name;
	int col;
	int mode;
	int a;
	bool cmp;
	char cmpname[8];

	for (int i = 0; i < codesize; ++i)
	{
		name = OpInfo[code[i].op].Name;
		mode = OpInfo[code[i].op].Mode;
		a = code[i].a;
		cmp = (mode & MODE_ATYPE) == MODE_ACMP;

		// String comparison encodes everything in a single instruction.
		if (code[i].op == OP_CMPS)
		{
			switch (a & CMP_METHOD_MASK)
			{
			case CMP_EQ:	name = "beq";	break;
			case CMP_LT:	name = "blt";	break;
			case CMP_LE:	name = "ble";	break;
			}
			mode = MODE_AIMMZ;
			mode |= (a & CMP_BK) ? MODE_BKS : MODE_BS;
			mode |= (a & CMP_CK) ? MODE_CKS : MODE_CS;
			a &= CMP_CHECK | CMP_APPROX;
			cmp = true;
		}
		if (cmp)
		{ // Comparison instruction. Modify name for inverted test.
			if (!(a & CMP_CHECK))
			{
				strcpy(cmpname, name);
				if (name[1] == 'e')
				{ // eq -> ne
					cmpname[1] = 'n', cmpname[2] = 'e';
				}
				else if (name[2] == 't')
				{ // lt -> ge
					cmpname[1] = 'g', cmpname[2] = 'e';
				}
				else
				{ // le -> gt
					cmpname[1] = 'g', cmpname[2] = 't';
				}
				name = cmpname;
			}
		}
		printf_wrapper(out, "%08x: %02x%02x%02x%02x %-8s", i << 2, code[i].op, code[i].a, code[i].b, code[i].c, name);
		col = 0;
		switch (code[i].op)
		{
		case OP_JMP:
		case OP_TRY:
			col = printf_wrapper(out, "%08x", (i + 1 + code[i].i24) << 2);
			break;

		case OP_PARAMI:
			col = printf_wrapper(out, "%d", code[i].i24);
			break;

		case OP_CALL_K:
		case OP_TAIL_K:
			callfunc = (VMFunction *)func->KonstA[code[i].a].o;
			callname = callfunc->Name != NAME_None ? callfunc->Name : "[anonfunc]";
			col = printf_wrapper(out, "%.23s,%d", callname, code[i].b);
			if (code[i].op == OP_CALL_K)
			{
				col += printf_wrapper(out, ",%d", code[i].c);
			}
			break;

		case OP_RET:
			if (code[i].b != REGT_NIL)
			{
				if (a == RET_FINAL)
				{
					col = print_reg(out, 0, code[i].i16u, MODE_PARAM, 16, func);
				}
				else
				{
					col = print_reg(out, 0, a & ~RET_FINAL, (mode & MODE_ATYPE) >> MODE_ASHIFT, 24, func);
					col += print_reg(out, col, code[i].i16u, MODE_PARAM, 16, func);
					if (a & RET_FINAL)
					{
						col += printf_wrapper(out, " [final]");
					}
				}
			}
			break;

		case OP_RETI:
			if (a == RET_FINAL)
			{
				col = printf_wrapper(out, "%d", code[i].i16);
			}
			else
			{
				col = print_reg(out, 0, a & ~RET_FINAL, (mode & MODE_ATYPE) >> MODE_ASHIFT, 24, func);
				col += print_reg(out, col, code[i].i16, MODE_IMMS, 16, func);
				if (a & RET_FINAL)
				{
					col += printf_wrapper(out, " [final]");
				}
			}
			break;

		case OP_FLOP:
			col = printf_wrapper(out, "f%d,f%d,%d", code[i].a, code[i].b, code[i].c);
			if (code[i].c < countof(FlopNames))
			{
				col += printf_wrapper(out, " [%s]", FlopNames[code[i].c]);
			}
			break;

		default:
			if ((mode & MODE_BCTYPE) == MODE_BCCAST)
			{
				switch (code[i].c)
				{
				case CAST_I2F:
					mode = MODE_AF | MODE_BI | MODE_CUNUSED;
					break;
				case CAST_I2S:
					mode = MODE_AS | MODE_BI | MODE_CUNUSED;
					break;
				case CAST_F2I:
					mode = MODE_AI | MODE_BF | MODE_CUNUSED;
					break;
				case CAST_F2S:
					mode = MODE_AS | MODE_BF | MODE_CUNUSED;
					break;
				case CAST_P2S:
					mode = MODE_AS | MODE_BP | MODE_CUNUSED;
					break;
				case CAST_S2I:
					mode = MODE_AI | MODE_BS | MODE_CUNUSED;
					break;
				case CAST_S2F:
					mode = MODE_AF | MODE_BS | MODE_CUNUSED;
					break;
				default:
					mode = MODE_AX | MODE_BX | MODE_CIMMZ;
					break;
				}
			}
			col = print_reg(out, 0, a, (mode & MODE_ATYPE) >> MODE_ASHIFT, 24, func);
			if ((mode & MODE_BCTYPE) == MODE_BCTHROW)
			{
				mode = (code[i].a == 0) ? (MODE_BP | MODE_CUNUSED) : (MODE_BKP | MODE_CUNUSED);
			}
			else if ((mode & MODE_BCTYPE) == MODE_BCCATCH)
			{
				switch (code[i].a)
				{
				case 0:
					mode = MODE_BUNUSED | MODE_CUNUSED;
					break;
				case 1:
					mode = MODE_BUNUSED | MODE_CP;
					break;
				case 2:
					mode = MODE_BP | MODE_CP;
					break;
				case 3:
					mode = MODE_BKP | MODE_CP;
					break;
				default:
					mode = MODE_BIMMZ | MODE_CIMMZ;
					break;
				}
			}
			if ((mode & (MODE_BTYPE | MODE_CTYPE)) == MODE_BCJOINT)
			{
				col += print_reg(out, col, code[i].i16u, (mode & MODE_BCTYPE) >> MODE_BCSHIFT, 16, func);
			}
			else
			{
				col += print_reg(out, col, code[i].b, (mode & MODE_BTYPE) >> MODE_BSHIFT, 24, func);
				col += print_reg(out, col, code[i].c, (mode & MODE_CTYPE) >> MODE_CSHIFT, 24, func);
			}
			break;
		}
		if (cmp && i + 1 < codesize)
		{
			if (code[i+1].op != OP_JMP)
			{ // comparison instructions must be followed by jump
				col += printf_wrapper(out, " => *!*!*!*\n");
			}
			else
			{ 
				col += printf_wrapper(out, " => %08x", (i + 2 + code[i+1].i24) << 2);
			}
		}
		if (col > 30)
		{
			col = 30;
		}
		printf_wrapper(out, "%*c", 30 - col, ';');
		if (!cmp && (code[i].op == OP_JMP || code[i].op == OP_TRY || code[i].op == OP_PARAMI))
		{
			printf_wrapper(out, "%d\n", code[i].i24);
		}
		else
		{
			printf_wrapper(out, "%d,%d,%d", code[i].a, code[i].b, code[i].c);
			if (cmp && i + 1 < codesize && code[i+1].op == OP_JMP)
			{
				printf_wrapper(out, ",%d\n", code[++i].i24);
			}
			else if (code[i].op == OP_CALL_K || code[i].op == OP_TAIL_K)
			{
				printf_wrapper(out, "  [%p]\n", callfunc);
			}
			else
			{
				printf_wrapper(out, "\n");
			}
		}
	}
}

static int print_reg(FILE *out, int col, int arg, int mode, int immshift, const VMScriptFunction *func)
{
	if (mode == MODE_UNUSED || mode == MODE_CMP)
	{
		return 0;
	}
	if (col > 0)
	{
		col = printf_wrapper(out, ",");
	}
	switch(mode)
	{
	case MODE_I:
		return col+printf_wrapper(out, "d%d", arg);
	case MODE_F:
		return col+printf_wrapper(out, "f%d", arg);
	case MODE_S:
		return col+printf_wrapper(out, "s%d", arg);
	case MODE_P:
		return col+printf_wrapper(out, "a%d", arg);
	case MODE_V:
		return col+printf_wrapper(out, "v%d", arg);

	case MODE_KI:
		if (func != NULL)
		{
			return col+printf_wrapper(out, "%d", func->KonstD[arg]);
		}
		return printf_wrapper(out, "kd%d", arg);
	case MODE_KF:
		if (func != NULL)
		{
			return col+printf_wrapper(out, "%#g", func->KonstF[arg]);
		}
		return col+printf_wrapper(out, "kf%d", arg);
	case MODE_KS:
		if (func != NULL)
		{
			return col+printf_wrapper(out, "\"%.27s\"", func->KonstS[arg].GetChars());
		}
		return col+printf_wrapper(out, "ks%d", arg);
	case MODE_KP:
		if (func != NULL)
		{
			return col+printf_wrapper(out, "%p", func->KonstA[arg]);
		}
		return col+printf_wrapper(out, "ka%d", arg);
	case MODE_KV:
		if (func != NULL)
		{
			return col+printf_wrapper(out, "(%f,%f,%f)", func->KonstF[arg], func->KonstF[arg+1], func->KonstF[arg+2]);
		}
		return col+printf_wrapper(out, "kv%d", arg);

	case MODE_IMMS:
		return col+printf_wrapper(out, "%d", (arg << immshift) >> immshift);

	case MODE_IMMZ:
		return col+printf_wrapper(out, "%d", arg);

	case MODE_PARAM:
		{
			int regtype, regnum;
#ifdef __BIG_ENDIAN__
			regtype = (arg >> 8) & 255;
			regnum = arg & 255;
#else
			regtype = arg & 255;
			regnum = (arg >> 8) & 255;
#endif
			switch (regtype & (REGT_TYPE | REGT_KONST | REGT_MULTIREG))
			{
			case REGT_INT:
				return col+printf_wrapper(out, "d%d", regnum);
			case REGT_FLOAT:
				return col+printf_wrapper(out, "f%d", regnum);
			case REGT_STRING:
				return col+printf_wrapper(out, "s%d", regnum);
			case REGT_POINTER:
				return col+printf_wrapper(out, "a%d", regnum);
			case REGT_FLOAT | REGT_MULTIREG:
				return col+printf_wrapper(out, "v%d", regnum);
			case REGT_INT | REGT_KONST:
				return col+print_reg(out, 0, regnum, MODE_KI, 0, func);
			case REGT_FLOAT | REGT_KONST:
				return col+print_reg(out, 0, regnum, MODE_KF, 0, func);
			case REGT_STRING | REGT_KONST:
				return col+print_reg(out, 0, regnum, MODE_KS, 0, func);
			case REGT_POINTER | REGT_KONST:
				return col+print_reg(out, 0, regnum, MODE_KP, 0, func);
			case REGT_FLOAT | REGT_MULTIREG | REGT_KONST:
				return col+print_reg(out, 0, regnum, MODE_KV, 0, func);
			default:
				if (regtype == REGT_NIL)
				{
					return col+printf_wrapper(out, "nil");
				}
				return col+printf_wrapper(out, "param[t=%d,%c,%c,n=%d]",
					regtype & REGT_TYPE,
					regtype & REGT_KONST ? 'k' : 'r',
					regtype & REGT_MULTIREG ? 'm' : 's',
					regnum);
			}
		}

	default:
		return col+printf_wrapper(out, "$%d", arg);
	}
	return col;
}