NetBSD-5.0.2/sys/arch/powerpc/powerpc/db_disasm.c
/* $NetBSD: db_disasm.c,v 1.23 2008/02/20 19:12:13 phx Exp $ */
/* $OpenBSD: db_disasm.c,v 1.2 1996/12/28 06:21:48 rahnds Exp $ */
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: db_disasm.c,v 1.23 2008/02/20 19:12:13 phx Exp $");
#include <sys/param.h>
#include <sys/proc.h>
#include <sys/systm.h>
#include <machine/db_machdep.h>
#include <ddb/db_access.h>
#include <ddb/db_sym.h>
#include <ddb/db_variables.h>
#include <ddb/db_interface.h>
#include <ddb/db_output.h>
enum function_mask {
Op_A = 0x00000001,
Op_B = 0x00000002,
Op_BI = 0x00000004,
Op_BO = 0x00000008,
Op_CRM = 0x00000010,
Op_D = 0x00000020,
Op_ST = 0x00000020, /* Op_S for store-operations, same as D */
Op_S = 0x00000040, /* S-field is swapped with A-field */
Op_FM = Op_D | Op_S, /* kludge (reduce Op_s) */
Op_IMM = 0x00000080,
Op_LK = 0x00000100,
Op_Rc = 0x00000200,
Op_AA = Op_LK | Op_Rc, /* kludge (reduce Op_s) */
Op_LKM = Op_AA,
Op_RcM = Op_AA,
Op_OE = 0x00000400,
Op_SR = 0x00000800,
Op_TO = 0x00001000,
Op_sign = 0x00002000,
Op_const = 0x00004000,
Op_SIMM = Op_const | Op_sign,
Op_UIMM = Op_const,
Op_d = Op_const | Op_sign,
Op_crbA = 0x00008000,
Op_crbB = 0x00010000,
Op_WS = Op_crbB, /* kludge, same field as crbB */
Op_rSH = Op_crbB, /* kludge, same field as crbB */
Op_crbD = 0x00020000,
Op_crfD = 0x00040000,
Op_crfS = 0x00080000,
Op_ds = 0x00100000,
Op_me = 0x00200000,
Op_spr = 0x00400000,
Op_dcr = Op_spr, /* out of bits - cheat with Op_spr */
Op_tbr = 0x00800000,
Op_L = 0x01000000,
Op_BD = 0x02000000,
Op_LI = 0x04000000,
Op_C = 0x08000000,
Op_NB = 0x10000000,
Op_sh_mb_sh = 0x20000000,
Op_sh = 0x40000000,
Op_SH = Op_sh | Op_sh_mb_sh,
Op_mb = 0x80000000,
Op_MB = Op_mb | Op_sh_mb_sh,
Op_ME = Op_MB,
};
struct opcode {
const char *name;
u_int32_t mask;
u_int32_t code;
enum function_mask func;
};
typedef u_int32_t instr_t;
typedef void (op_class_func) (instr_t, vaddr_t);
u_int32_t extract_field(u_int32_t value, u_int32_t base, u_int32_t width);
void disasm_fields(const struct opcode *popcode, instr_t instr, vaddr_t loc,
char *disasm_str, size_t slen);
void dis_ppc(const struct opcode *opcodeset, instr_t instr, vaddr_t loc);
op_class_func op_ill, op_base;
op_class_func op_cl_x13, op_cl_x1e, op_cl_x1f;
op_class_func op_cl_x3a, op_cl_x3b;
op_class_func op_cl_x3e, op_cl_x3f;
op_class_func *opcodes_base[] = {
/*x00*/ op_ill, op_ill, op_base, op_ill,
/*x04*/ op_ill, op_ill, op_ill, op_base,
/*x08*/ op_base, op_base, op_base, op_base,
/*x0C*/ op_base, op_base, op_base/*XXX*/, op_base/*XXX*/,
/*x10*/ op_base, op_base, op_base, op_cl_x13,
/*x14*/ op_base, op_base, op_ill, op_base,
/*x18*/ op_base, op_base, op_base, op_base,
/*x1C*/ op_base, op_base, op_cl_x1e, op_cl_x1f,
/*x20*/ op_base, op_base, op_base, op_base,
/*x24*/ op_base, op_base, op_base, op_base,
/*x28*/ op_base, op_base, op_base, op_base,
/*x2C*/ op_base, op_base, op_base, op_base,
/*x30*/ op_base, op_base, op_base, op_base,
/*x34*/ op_base, op_base, op_base, op_base,
/*x38*/ op_ill, op_ill, op_cl_x3a, op_cl_x3b,
/*x3C*/ op_ill, op_ill, op_cl_x3e, op_cl_x3f
};
/* This table could be modified to make significant the "reserved" fields
* of the opcodes, But I didn't feel like it when typing in the table,
* I would recommend that this table be looked over for errors,
* This was derived from the table in Appendix A.2 of (Mot part # MPCFPE/AD)
* PowerPC Microprocessor Family: The Programming Environments
*/
const struct opcode opcodes[] = {
{ "tdi", 0xfc000000, 0x08000000, Op_TO | Op_A | Op_SIMM },
{ "twi", 0xfc000000, 0x0c000000, Op_TO | Op_A | Op_SIMM },
{ "mulli", 0xfc000000, 0x1c000000, Op_D | Op_A | Op_SIMM },
{ "subfic", 0xfc000000, 0x20000000, Op_D | Op_A | Op_SIMM },
{ "cmpli", 0xfc000000, 0x28000000, Op_crfD | Op_L | Op_A | Op_SIMM },
{ "cmpi", 0xfc000000, 0x2c000000, Op_crfD | Op_L | Op_A | Op_SIMM },
{ "addic", 0xfc000000, 0x30000000, Op_D | Op_A | Op_SIMM },
{ "addic.", 0xfc000000, 0x34000000, Op_D | Op_A | Op_SIMM },
{ "addi", 0xfc000000, 0x38000000, Op_D | Op_A | Op_SIMM },
{ "addis", 0xfc000000, 0x3c000000, Op_D | Op_A | Op_SIMM },
{ "bc", 0xfc000000, 0x40000000, Op_BO | Op_BI | Op_BD | Op_AA | Op_LK },
{ "sc", 0xffffffff, 0x44000002, Op_BO | Op_BI | Op_BD | Op_AA | Op_LK },
{ "b", 0xfc000000, 0x48000000, Op_LI | Op_AA | Op_LK },
{ "rlwimi", 0xfc000000, 0x50000000, Op_S | Op_A | Op_SH | Op_MB | Op_ME | Op_Rc },
{ "rlwinm", 0xfc000000, 0x54000000, Op_S | Op_A | Op_SH | Op_MB | Op_ME | Op_Rc },
{ "rlwnm", 0xfc000000, 0x5c000000, Op_S | Op_A | Op_SH | Op_MB | Op_ME | Op_Rc },
{ "ori", 0xfc000000, 0x60000000, Op_S | Op_A | Op_UIMM },
{ "oris", 0xfc000000, 0x64000000, Op_S | Op_A | Op_UIMM },
{ "xori", 0xfc000000, 0x68000000, Op_S | Op_A | Op_UIMM },
{ "xoris", 0xfc000000, 0x6c000000, Op_S | Op_A | Op_UIMM },
{ "andi.", 0xfc000000, 0x70000000, Op_S | Op_A | Op_UIMM },
{ "andis.", 0xfc000000, 0x74000000, Op_S | Op_A | Op_UIMM },
{ "lwz", 0xfc000000, 0x80000000, Op_D | Op_A | Op_d },
{ "lwzu", 0xfc000000, 0x84000000, Op_D | Op_A | Op_d },
{ "lbz", 0xfc000000, 0x88000000, Op_D | Op_A | Op_d },
{ "lbzu", 0xfc000000, 0x8c000000, Op_D | Op_A | Op_d },
{ "stw", 0xfc000000, 0x90000000, Op_ST | Op_A | Op_d },
{ "stwu", 0xfc000000, 0x94000000, Op_ST | Op_A | Op_d },
{ "stb", 0xfc000000, 0x98000000, Op_ST | Op_A | Op_d },
{ "stbu", 0xfc000000, 0x9c000000, Op_ST | Op_A | Op_d },
{ "lhz", 0xfc000000, 0xa0000000, Op_D | Op_A | Op_d },
{ "lhzu", 0xfc000000, 0xa4000000, Op_D | Op_A | Op_d },
{ "lha", 0xfc000000, 0xa8000000, Op_D | Op_A | Op_d },
{ "lhau", 0xfc000000, 0xac000000, Op_D | Op_A | Op_d },
{ "sth", 0xfc000000, 0xb0000000, Op_ST | Op_A | Op_d },
{ "sthu", 0xfc000000, 0xb4000000, Op_ST | Op_A | Op_d },
{ "lmw", 0xfc000000, 0xb8000000, Op_D | Op_A | Op_d },
{ "stmw", 0xfc000000, 0xbc000000, Op_S | Op_A | Op_d },
{ "lfs", 0xfc000000, 0xc0000000, Op_D | Op_A | Op_d },
{ "lfsu", 0xfc000000, 0xc4000000, Op_D | Op_A | Op_d },
{ "lfd", 0xfc000000, 0xc8000000, Op_D | Op_A | Op_d },
{ "lfdu", 0xfc000000, 0xcc000000, Op_D | Op_A | Op_d },
{ "stfs", 0xfc000000, 0xd0000000, Op_ST | Op_A | Op_d },
{ "stfsu", 0xfc000000, 0xd4000000, Op_ST | Op_A | Op_d },
{ "stfd", 0xfc000000, 0xd8000000, Op_ST | Op_A | Op_d },
{ "stfdu", 0xfc000000, 0xdc000000, Op_ST | Op_A | Op_d },
{ "", 0x0, 0x0, 0 }
};
/* 13 * 4 = 4c */
const struct opcode opcodes_13[] = {
/* 0x13 << 2 */
{ "mcrf", 0xfc0007fe, 0x4c000000, Op_crfD | Op_crfS },
{ "bclr", 0xfc0007fe, 0x4c000020, Op_BO | Op_BI | Op_LK },
{ "crnor", 0xfc0007fe, 0x4c000042, Op_crbD | Op_crbA | Op_crbB },
{ "rfi", 0xfc0007fe, 0x4c000064, 0 },
{ "crandc", 0xfc0007fe, 0x4c000102, Op_BO | Op_BI | Op_LK },
{ "isync", 0xfc0007fe, 0x4c00012c, 0 },
{ "crxor", 0xfc0007fe, 0x4c000182, Op_crbD | Op_crbA | Op_crbB },
{ "crnand", 0xfc0007fe, 0x4c0001c2, Op_crbD | Op_crbA | Op_crbB },
{ "crand", 0xfc0007fe, 0x4c000202, Op_crbD | Op_crbA | Op_crbB },
{ "creqv", 0xfc0007fe, 0x4c000242, Op_crbD | Op_crbA | Op_crbB },
{ "crorc", 0xfc0007fe, 0x4c000342, Op_crbD | Op_crbA | Op_crbB },
{ "cror", 0xfc0007fe, 0x4c000382, Op_crbD | Op_crbA | Op_crbB },
{ "bcctr", 0xfc0007fe, 0x4c000420, Op_BO | Op_BI | Op_LK },
{ "", 0x0, 0x0, 0 }
};
/* 1e * 4 = 78 */
const struct opcode opcodes_1e[] = {
{ "rldicl", 0xfc00001c, 0x78000000, Op_S | Op_A | Op_sh | Op_mb | Op_Rc },
{ "rldicr", 0xfc00001c, 0x78000004, Op_S | Op_A | Op_sh | Op_me | Op_Rc },
{ "rldic", 0xfc00001c, 0x78000008, Op_S | Op_A | Op_sh | Op_mb | Op_Rc },
{ "rldimi", 0xfc00001c, 0x7800000c, Op_S | Op_A | Op_sh | Op_mb | Op_Rc },
{ "rldcl", 0xfc00003e, 0x78000010, Op_S | Op_A | Op_B | Op_mb | Op_Rc },
{ "rldcr", 0xfc00003e, 0x78000012, Op_S | Op_A | Op_B | Op_me | Op_Rc },
{ "", 0x0, 0x0, 0 }
};
/* 1f * 4 = 7c */
const struct opcode opcodes_1f[] = {
/* 1f << 2 */
{ "cmp", 0xfc0007fe, 0x7c000000, Op_crfD | Op_A | Op_B },
{ "tw", 0xfc0007fe, 0x7c000008, Op_TO | Op_A | Op_B },
{ "subfc", 0xfc0003fe, 0x7c000010, Op_D | Op_A | Op_B | Op_OE | Op_Rc },
{ "mulhdu", 0xfc0007fe, 0x7c000012, Op_D | Op_A | Op_B | Op_Rc },
{ "addc", 0xfc0003fe, 0x7c000014, Op_D | Op_A | Op_B | Op_OE | Op_Rc },
{ "mulhwu", 0xfc0007fe, 0x7c000016, Op_D | Op_A | Op_B | Op_Rc },
{ "mfcr", 0xfc0007fe, 0x7c000026, Op_D },
{ "lwarx", 0xfc0007fe, 0x7c000028, Op_D | Op_A | Op_B },
{ "ldx", 0xfc0007fe, 0x7c00002a, Op_D | Op_A | Op_B },
{ "lwzx", 0xfc0007fe, 0x7c00002e, Op_D | Op_A | Op_B },
{ "slw", 0xfc0007fe, 0x7c000030, Op_D | Op_A | Op_B | Op_Rc },
{ "cntlzw", 0xfc0007fe, 0x7c000034, Op_D | Op_A | Op_Rc },
{ "sld", 0xfc0007fe, 0x7c000036, Op_D | Op_A | Op_B | Op_Rc },
{ "and", 0xfc0007fe, 0x7c000038, Op_D | Op_A | Op_B | Op_Rc },
{ "cmpl", 0xfc0007fe, 0x7c000040, Op_crfD | Op_L | Op_A | Op_B },
{ "subf", 0xfc0003fe, 0x7c000050, Op_D | Op_A | Op_B | Op_OE | Op_Rc },
{ "ldux", 0xfc0007fe, 0x7c00006a, Op_D | Op_A | Op_B },
{ "dcbst", 0xfc0007fe, 0x7c00006c, Op_A | Op_B },
{ "lwzux", 0xfc0007fe, 0x7c00006e, Op_D | Op_A | Op_B },
{ "cntlzd", 0xfc0007fe, 0x7c000074, Op_S | Op_A | Op_Rc },
{ "andc", 0xfc0007fe, 0x7c000078, Op_S | Op_A | Op_B | Op_Rc },
{ "td", 0xfc0007fe, 0x7c000088, Op_TO | Op_A | Op_B },
{ "mulhd", 0xfc0007fe, 0x7c000092, Op_D | Op_A | Op_B | Op_Rc },
{ "mulhw", 0xfc0007fe, 0x7c000096, Op_D | Op_A | Op_B | Op_Rc },
{ "mfmsr", 0xfc0007fe, 0x7c0000a6, Op_D },
{ "ldarx", 0xfc0007fe, 0x7c0000a8, Op_D | Op_A | Op_B },
{ "dcbf", 0xfc0007fe, 0x7c0000ac, Op_A | Op_B },
{ "lbzx", 0xfc0007fe, 0x7c0000ae, Op_D | Op_A | Op_B },
{ "neg", 0xfc0003fe, 0x7c0000d0, Op_D | Op_A | Op_OE | Op_Rc },
{ "lbzux", 0xfc0007fe, 0x7c0000ee, Op_D | Op_A | Op_B },
{ "nor", 0xfc0007fe, 0x7c0000f8, Op_S | Op_A | Op_B | Op_Rc },
{ "wrtee", 0xfc0003ff, 0x7c000106, Op_S },
{ "subfe", 0xfc0003fe, 0x7c000110, Op_D | Op_A | Op_B | Op_OE | Op_Rc },
{ "adde", 0xfc0003fe, 0x7c000114, Op_D | Op_A | Op_B | Op_OE | Op_Rc },
{ "mtcrf", 0xfc0007fe, 0x7c000120, Op_S | Op_CRM },
{ "mtmsr", 0xfc0007fe, 0x7c000124, Op_S },
{ "stdx", 0xfc0007fe, 0x7c00012a, Op_ST | Op_A | Op_B },
{ "stwcx.", 0xfc0007ff, 0x7c00012d, Op_ST | Op_A | Op_B },
{ "stwx", 0xfc0007fe, 0x7c00012e, Op_ST | Op_A | Op_B },
{ "wrteei", 0xfc0003fe, 0x7c000146, 0 }, /* XXX: out of flags! */
{ "stdux", 0xfc0007fe, 0x7c00016a, Op_ST | Op_A | Op_B },
{ "stwux", 0xfc0007fe, 0x7c00016e, Op_ST | Op_A | Op_B },
{ "subfze", 0xfc0003fe, 0x7c000190, Op_D | Op_A | Op_OE | Op_Rc },
{ "addze", 0xfc0003fe, 0x7c000194, Op_D | Op_A | Op_OE | Op_Rc },
{ "mtsr", 0xfc0007fe, 0x7c0001a4, Op_S | Op_SR },
{ "stdcx.", 0xfc0007ff, 0x7c0001ad, Op_ST | Op_A | Op_B },
{ "stbx", 0xfc0007fe, 0x7c0001ae, Op_ST | Op_A | Op_B },
{ "subfme", 0xfc0003fe, 0x7c0001d0, Op_D | Op_A | Op_OE | Op_Rc },
{ "mulld", 0xfc0003fe, 0x7c0001d2, Op_D | Op_A | Op_B | Op_OE | Op_Rc },
{ "addme", 0xfc0003fe, 0x7c0001d4, Op_D | Op_A | Op_OE | Op_Rc },
{ "mullw", 0xfc0003fe, 0x7c0001d6, Op_D | Op_A | Op_B | Op_OE | Op_Rc },
{ "mtsrin", 0xfc0007fe, 0x7c0001e4, Op_S | Op_B },
{ "dcbtst", 0xfc0007fe, 0x7c0001ec, Op_A | Op_B },
{ "stbux", 0xfc0007fe, 0x7c0001ee, Op_ST | Op_A | Op_B },
{ "add", 0xfc0003fe, 0x7c000214, Op_D | Op_A | Op_B | Op_OE | Op_Rc },
{ "dcbt", 0xfc0007fe, 0x7c00022c, Op_A | Op_B },
{ "lhzx", 0xfc0007ff, 0x7c00022e, Op_D | Op_A | Op_B },
{ "eqv", 0xfc0007fe, 0x7c000238, Op_S | Op_A | Op_B | Op_Rc },
{ "tlbie", 0xfc0007fe, 0x7c000264, Op_B },
{ "eciwx", 0xfc0007fe, 0x7c00026c, Op_D | Op_A | Op_B },
{ "lhzux", 0xfc0007fe, 0x7c00026e, Op_D | Op_A | Op_B },
{ "xor", 0xfc0007fe, 0x7c000278, Op_S | Op_A | Op_B | Op_Rc },
{ "mfdcr", 0xfc0007fe, 0x7c000286, Op_D | Op_dcr },
{ "mfspr", 0xfc0007fe, 0x7c0002a6, Op_D | Op_spr },
{ "lwax", 0xfc0007fe, 0x7c0002aa, Op_D | Op_A | Op_B },
{ "lhax", 0xfc0007fe, 0x7c0002ae, Op_D | Op_A | Op_B },
{ "tlbia", 0xfc0007fe, 0x7c0002e4, 0 },
{ "mftb", 0xfc0007fe, 0x7c0002e6, Op_D | Op_tbr },
{ "lwaux", 0xfc0007fe, 0x7c0002ea, Op_D | Op_A | Op_B },
{ "lhaux", 0xfc0007fe, 0x7c0002ee, Op_D | Op_A | Op_B },
{ "sthx", 0xfc0007fe, 0x7c00032e, Op_ST | Op_A | Op_B },
{ "orc", 0xfc0007fe, 0x7c000338, Op_S | Op_A | Op_B | Op_Rc },
{ "ecowx", 0xfc0007fe, 0x7c00036c, Op_ST | Op_A | Op_B | Op_Rc },
{ "slbie", 0xfc0007fc, 0x7c000364, Op_B },
{ "sthux", 0xfc0007fe, 0x7c00036e, Op_ST | Op_A | Op_B },
{ "or", 0xfc0007fe, 0x7c000378, Op_S | Op_A | Op_B | Op_Rc },
{ "mtdcr", 0xfc0007fe, 0x7c000386, Op_S | Op_dcr },
{ "divdu", 0xfc0003fe, 0x7c000392, Op_D | Op_A | Op_B | Op_OE | Op_Rc },
{ "divwu", 0xfc0003fe, 0x7c000396, Op_D | Op_A | Op_B | Op_OE | Op_Rc },
{ "mtspr", 0xfc0007fe, 0x7c0003a6, Op_S | Op_spr },
{ "dcbi", 0xfc0007fe, 0x7c0003ac, Op_A | Op_B },
{ "nand", 0xfc0007fe, 0x7c0003b8, Op_S | Op_A | Op_B | Op_Rc },
{ "dcread", 0xfc0007fe, 0x7c0003cc, Op_D | Op_A | Op_B },
{ "divd", 0xfc0003fe, 0x7c0003d2, Op_S | Op_A | Op_B | Op_OE | Op_Rc },
{ "divw", 0xfc0003fe, 0x7c0003d6, Op_S | Op_A | Op_B | Op_OE | Op_Rc },
{ "slbia", 0xfc0003fe, 0x7c0003e4, Op_S | Op_A | Op_B | Op_OE | Op_Rc },
{ "mcrxr", 0xfc0007fe, 0x7c000400, Op_crfD },
{ "lswx", 0xfc0007fe, 0x7c00042a, Op_D | Op_A | Op_B },
{ "lwbrx", 0xfc0007fe, 0x7c00042c, Op_D | Op_A | Op_B },
{ "lfsx", 0xfc0007fe, 0x7c00042e, Op_D | Op_A | Op_B },
{ "srw", 0xfc0007fe, 0x7c000430, Op_S | Op_A | Op_B | Op_Rc },
{ "srd", 0xfc0007fe, 0x7c000436, Op_S | Op_A | Op_B | Op_Rc },
{ "tlbsync", 0xfc0007fe, 0x7c00046c, 0 },
{ "lfsux", 0xfc0007fe, 0x7c00046e, Op_D | Op_A | Op_B },
{ "mfsr", 0xfc0007fe, 0x7c0004a6, Op_D | Op_SR },
{ "lswi", 0xfc0007fe, 0x7c0004aa, Op_D | Op_A | Op_NB },
{ "sync", 0xfc0007fe, 0x7c0004ac, 0 },
{ "lfdx", 0xfc0007fe, 0x7c0004ae, Op_D | Op_A | Op_B },
{ "lfdux", 0xfc0007fe, 0x7c0004ee, Op_D | Op_A | Op_B },
{ "mfsrin", 0xfc0007fe, 0x7c000526, Op_D | Op_B },
{ "stswx", 0xfc0007fe, 0x7c00052a, Op_ST | Op_A | Op_B },
{ "stwbrx", 0xfc0007fe, 0x7c00052c, Op_ST | Op_A | Op_B },
{ "stfsx", 0xfc0007fe, 0x7c00052e, Op_ST | Op_A | Op_B },
{ "stfsux", 0xfc0007fe, 0x7c00056e, Op_ST | Op_A | Op_B },
{ "stswi", 0xfc0007fe, 0x7c0005aa, Op_ST | Op_A | Op_NB },
{ "stfdx", 0xfc0007fe, 0x7c0005ae, Op_ST | Op_A | Op_B },
{ "stfdux", 0xfc0007fe, 0x7c0005ee, Op_ST | Op_A | Op_B },
{ "lhbrx", 0xfc0007fe, 0x7c00062c, Op_D | Op_A | Op_B },
{ "sraw", 0xfc0007fe, 0x7c000630, Op_S | Op_A | Op_B },
{ "srad", 0xfc0007fe, 0x7c000634, Op_S | Op_A | Op_B | Op_Rc },
{ "srawi", 0xfc0007fe, 0x7c000670, Op_S | Op_A | Op_rSH | Op_Rc },
{ "sradi", 0xfc0007fc, 0x7c000674, Op_S | Op_A | Op_sh },
{ "eieio", 0xfc0007fe, 0x7c0006ac, 0 },
{ "tlbsx", 0xfc0007fe, 0x7c000724, Op_S | Op_A | Op_B | Op_Rc },
{ "sthbrx", 0xfc0007fe, 0x7c00072c, Op_ST | Op_A | Op_B },
{ "extsh", 0xfc0007fe, 0x7c000734, Op_S | Op_A | Op_Rc },
{ "tlbre", 0xfc0007fe, 0x7c000764, Op_D | Op_A | Op_WS },
{ "extsb", 0xfc0007fe, 0x7c000774, Op_S | Op_A | Op_Rc },
{ "icbi", 0xfc0007fe, 0x7c0007ac, Op_A | Op_B },
{ "tlbwe", 0xfc0007fe, 0x7c0007a4, Op_S | Op_A | Op_WS },
{ "stfiwx", 0xfc0007fe, 0x7c0007ae, Op_ST | Op_A | Op_B },
{ "extsw", 0xfc0007fe, 0x7c0007b4, Op_S | Op_A | Op_Rc },
{ "dcbz", 0xfc0007fe, 0x7c0007ec, Op_A | Op_B },
{ "", 0x0, 0x0, 0 }
};
/* 3a * 4 = e8 */
const struct opcode opcodes_3a[] = {
{ "ld", 0xfc000003, 0xe8000000, Op_D | Op_A | Op_ds },
{ "ldu", 0xfc000003, 0xe8000001, Op_D | Op_A | Op_ds },
{ "lwa", 0xfc000003, 0xe8000002, Op_D | Op_A | Op_ds },
{ "", 0x0, 0x0, 0 }
};
/* 3b * 4 = ec */
const struct opcode opcodes_3b[] = {
{ "fdivs", 0xfc00003e, 0xec000024, Op_D | Op_A | Op_B | Op_Rc },
{ "fsubs", 0xfc00003e, 0xec000028, Op_D | Op_A | Op_B | Op_Rc },
{ "fadds", 0xfc00003e, 0xec00002a, Op_D | Op_A | Op_B | Op_Rc },
{ "fsqrts", 0xfc00003e, 0xec00002c, Op_D | Op_B | Op_Rc },
{ "fres", 0xfc00003e, 0xec000030, Op_D | Op_B | Op_Rc },
{ "fmuls", 0xfc00003e, 0xec000032, Op_D | Op_A | Op_C | Op_Rc },
{ "fmsubs", 0xfc00003e, 0xec000038, Op_D | Op_A | Op_B | Op_C | Op_Rc },
{ "fmadds", 0xfc00003e, 0xec00003a, Op_D | Op_A | Op_B | Op_C | Op_Rc },
{ "fnmsubs", 0xfc00003e, 0xec00003c, Op_D | Op_A | Op_B | Op_C | Op_Rc },
{ "fnmadds", 0xfc00003e, 0xec00003e, Op_D | Op_A | Op_B | Op_C | Op_Rc },
{ "", 0x0, 0x0, 0 }
};
/* 3e * 4 = f8 */
const struct opcode opcodes_3e[] = {
{ "std", 0xfc000003, 0xf8000000, Op_ST | Op_A | Op_ds },
{ "stdu", 0xfc000003, 0xf8000001, Op_ST | Op_A | Op_ds },
{ "", 0x0, 0x0, 0 }
};
/* 3f * 4 = fc */
const struct opcode opcodes_3f[] = {
{ "fcmpu", 0xfc0007fe, 0xfc000000, Op_crfD | Op_A | Op_B },
{ "frsp", 0xfc0007fe, 0xfc000018, Op_D | Op_B | Op_Rc },
{ "fctiw", 0xfc0007fe, 0xfc00001c, Op_D | Op_B | Op_Rc },
{ "fctiwz", 0xfc0007fe, 0xfc00001e, Op_D | Op_B | Op_Rc },
{ "fdiv", 0xfc00003e, 0xfc000024, Op_D | Op_A | Op_B | Op_Rc },
{ "fsub", 0xfc00003e, 0xfc000028, Op_D | Op_A | Op_B | Op_Rc },
{ "fadd", 0xfc00003e, 0xfc00002a, Op_D | Op_A | Op_B | Op_Rc },
{ "fsqrt", 0xfc00003e, 0xfc00002c, Op_D | Op_B | Op_Rc },
{ "fsel", 0xfc00003e, 0xfc00002e, Op_D | Op_A | Op_B | Op_C | Op_Rc },
{ "fmul", 0xfc00003e, 0xfc000032, Op_D | Op_A | Op_C | Op_Rc },
{ "frsqrte", 0xfc00003e, 0xfc000034, Op_D | Op_B | Op_Rc },
{ "fmsub", 0xfc00003e, 0xfc000038, Op_D | Op_A | Op_B | Op_C | Op_Rc },
{ "fmadd", 0xfc00003e, 0xfc00003a, Op_D | Op_A | Op_B | Op_C | Op_Rc },
{ "fnmsub", 0xfc00003e, 0xfc00003c, Op_D | Op_A | Op_B | Op_C | Op_Rc },
{ "fnmadd", 0xfc00003e, 0xfc00003e, Op_D | Op_A | Op_B | Op_C | Op_Rc },
{ "fcmpo", 0xfc0007fe, 0xfc000040, Op_crfD | Op_A | Op_B },
{ "mtfsb1", 0xfc0007fe, 0xfc00004c, Op_crfD | Op_Rc },
{ "fneg", 0xfc0007fe, 0xfc000050, Op_D | Op_B | Op_Rc },
{ "mcrfs", 0xfc0007fe, 0xfc000080, Op_D | Op_B | Op_Rc },
{ "mtfsb0", 0xfc0007fe, 0xfc00008c, Op_crfD | Op_Rc },
{ "fmr", 0xfc0007fe, 0xfc000090, Op_D | Op_B | Op_Rc },
{ "mtfsfi", 0xfc0007fe, 0xfc00010c, Op_crfD | Op_IMM | Op_Rc },
{ "fnabs", 0xfc0007fe, 0xfc000110, Op_D | Op_B | Op_Rc },
{ "fabs", 0xfc0007fe, 0xfc000210, Op_D | Op_B | Op_Rc },
{ "mffs", 0xfc0007fe, 0xfc00048e, Op_D | Op_B | Op_Rc },
{ "mtfsf", 0xfc0007fe, 0xfc00058e, Op_FM | Op_B | Op_Rc },
{ "fctid", 0xfc0007fe, 0xfc00065c, Op_D | Op_B | Op_Rc },
{ "fctidz", 0xfc0007fe, 0xfc00065e, Op_D | Op_B | Op_Rc },
{ "fcfid", 0xfc0007fe, 0xfc00069c, Op_D | Op_B | Op_Rc },
{ "", 0x0, 0x0, 0 }
};
struct specialreg {
int reg;
const char *name;
};
const struct specialreg sprregs[] = {
{ 0x000, "mq" },
{ 0x001, "xer" },
{ 0x008, "lr" },
{ 0x009, "ctr" },
{ 0x012, "dsisr" },
{ 0x013, "dar" },
{ 0x016, "dec" },
{ 0x019, "sdr1" },
{ 0x01a, "srr0" },
{ 0x01b, "srr1" },
#ifdef PPC_IBM4XX
{ 0x100, "usprg0" },
#else
{ 0x100, "vrsave" },
#endif
{ 0x110, "sprg0" },
{ 0x111, "sprg1" },
{ 0x112, "sprg2" },
{ 0x113, "sprg3" },
{ 0x114, "sprg4" },
{ 0x115, "sprg5" },
{ 0x116, "sprg6" },
{ 0x117, "sprg7" },
{ 0x118, "asr" },
{ 0x11a, "aer" },
{ 0x11c, "tbl" },
{ 0x11d, "tbu" },
{ 0x11f, "pvr" },
{ 0x210, "ibat0u" },
{ 0x211, "ibat0l" },
{ 0x212, "ibat1u" },
{ 0x213, "ibat1l" },
{ 0x214, "ibat2u" },
{ 0x215, "ibat2l" },
{ 0x216, "ibat3u" },
{ 0x217, "ibat3l" },
{ 0x218, "dbat0u" },
{ 0x219, "dbat0l" },
{ 0x21a, "dbat1u" },
{ 0x21b, "dbat1l" },
{ 0x21c, "dbat2u" },
{ 0x21d, "dbat2l" },
{ 0x21e, "dbat3u" },
{ 0x21f, "dbat3l" },
{ 0x230, "ibat4u" },
{ 0x231, "ibat4l" },
{ 0x232, "ibat5u" },
{ 0x233, "ibat5l" },
{ 0x234, "ibat6u" },
{ 0x235, "ibat6l" },
{ 0x236, "ibat7u" },
{ 0x237, "ibat7l" },
{ 0x238, "dbat4u" },
{ 0x239, "dbat4l" },
{ 0x23a, "dbat5u" },
{ 0x23b, "dbat5l" },
{ 0x23c, "dbat6u" },
{ 0x23d, "dbat6l" },
{ 0x23e, "dbat7u" },
{ 0x23f, "dbat7l" },
{ 0x3b0, "zpr" },
{ 0x3b1, "pid" },
{ 0x3b3, "ccr0" },
{ 0x3b4, "iac3" },
{ 0x3b5, "iac4" },
{ 0x3b6, "dvc1" },
{ 0x3b7, "dvc2" },
{ 0x3b9, "sgr" },
{ 0x3ba, "dcwr" },
{ 0x3bb, "sler" },
{ 0x3bc, "su0r" },
{ 0x3bd, "dbcr1" },
{ 0x3d3, "icdbdr" },
{ 0x3d4, "esr" },
{ 0x3d5, "dear" },
{ 0x3d6, "evpr" },
{ 0x3d8, "tsr" },
{ 0x3da, "tcr" },
{ 0x3db, "pit" },
{ 0x3de, "srr2" },
{ 0x3df, "srr3" },
#ifdef PPC_IBM4XX
{ 0x3f0, "dbsr" },
{ 0x3f2, "dbcr0" },
{ 0x3f4, "iac1" },
{ 0x3f5, "iac2" },
{ 0x3f6, "dac1" },
{ 0x3f7, "dac2" },
#else
{ 0x3f0, "hid0" },
{ 0x3f1, "hid1" },
{ 0x3f2, "iabr" },
{ 0x3f3, "hid2" },
{ 0x3f5, "dabr" },
{ 0x3f6, "msscr0" },
{ 0x3f7, "msscr1" },
#endif
{ 0x3f9, "l2cr" },
{ 0x3fa, "dccr" },
{ 0x3fb, "iccr" },
{ 0x3ff, "pir" },
{ 0, NULL }
};
const struct specialreg dcrregs[] = {
{ 0x010, "sdram0_cfgaddr" },
{ 0x011, "sdram0_cfgdata" },
{ 0x012, "ebc0_cfgaddr" },
{ 0x013, "ebc0_cfgdata" },
{ 0x014, "dcp0_cfgaddr" },
{ 0x015, "dcp0_cfgdata" },
{ 0x018, "ocm0_isarc" },
{ 0x019, "ocm0_iscntl" },
{ 0x01a, "ocm0_dsarc" },
{ 0x01b, "ocm0_dscntl" },
{ 0x084, "plb0_besr" },
{ 0x086, "plb0_bear" },
{ 0x087, "plb0_acr" },
{ 0x0a0, "pob0_besr0" },
{ 0x0a2, "pob0_bear" },
{ 0x0a4, "pob0_besr1" },
{ 0x0b0, "cpc0_pllmr" },
{ 0x0b1, "cpc0_cr0" },
{ 0x0b2, "cpc0_cr1" },
{ 0x0b4, "cpc0_psr" },
{ 0x0b5, "cpc0_jtagid" },
{ 0x0b8, "cpc0_sr" },
{ 0x0b9, "cpc0_er" },
{ 0x0ba, "cpc0_fr" },
{ 0x0c0, "uic0_sr" },
{ 0x0c2, "uic0_er" },
{ 0x0c3, "uic0_cr" },
{ 0x0c4, "uic0_pr" },
{ 0x0c5, "uic0_tr" },
{ 0x0c6, "uic0_msr" },
{ 0x0c7, "uic0_vr" },
{ 0x0c8, "uic0_vcr" },
{ 0x100, "dma0_cr0" },
{ 0x101, "dma0_ct0" },
{ 0x102, "dma0_da0" },
{ 0x103, "dma0_sa0" },
{ 0x104, "dma0_sg0" },
{ 0x108, "dma0_cr1" },
{ 0x109, "dma0_ct1" },
{ 0x10a, "dma0_da1" },
{ 0x10b, "dma0_sa1" },
{ 0x10c, "dma0_sg1" },
{ 0x110, "dma0_cr2" },
{ 0x111, "dma0_ct2" },
{ 0x112, "dma0_da2" },
{ 0x113, "dma0_sa2" },
{ 0x114, "dma0_sg2" },
{ 0x118, "dma0_cr3" },
{ 0x119, "dma0_ct3" },
{ 0x11a, "dma0_da3" },
{ 0x11b, "dma0_sa3" },
{ 0x11c, "dma0_sg3" },
{ 0x120, "dma0_sr" },
{ 0x123, "dma0_sgc" },
{ 0x125, "dma0_slp" },
{ 0x126, "dma0_pol" },
{ 0x180, "mal0_cfg" },
{ 0x181, "mal0_esr" },
{ 0x182, "mal0_ier" },
{ 0x184, "mal0_txcasr" },
{ 0x185, "mal0_txcarr" },
{ 0x186, "mal0_txeobisr" },
{ 0x187, "mal0_txdeir" },
{ 0x190, "mal0_rxcasr" },
{ 0x191, "mal0_rxcarr" },
{ 0x192, "mal0_rxeobisr" },
{ 0x193, "mal0_rxdeir" },
{ 0x1a0, "mal0_txctp0r" },
{ 0x1a1, "mal0_txctp1r" },
{ 0x1a2, "mal0_txctp2r" },
{ 0x1a3, "mal0_txctp3r" },
{ 0x1c0, "mal0_rxctp0r" },
{ 0x1e0, "mal0_rcbs0" },
{ 0, NULL }
};
void
op_ill(instr_t instr, vaddr_t loc)
{
db_printf("illegal instruction %x\n", instr);
}
u_int32_t
extract_field(u_int32_t value, u_int32_t base, u_int32_t width)
{
u_int32_t mask = (1 << width) - 1;
return ((value >> base) & mask);
}
const struct opcode * search_op(const struct opcode *);
void
disasm_fields(const struct opcode *popcode, instr_t instr, vaddr_t loc,
char *disasm_str, size_t slen)
{
char * pstr;
enum function_mask func;
int len;
#define ADD_LEN(s) do { \
len = (s); \
slen -= len; \
pstr += len; \
} while(0)
#define APP_PSTR(fmt, arg) ADD_LEN(snprintf(pstr, slen, (fmt), (arg)))
#define APP_PSTRS(fmt) ADD_LEN(snprintf(pstr, slen, (fmt)))
pstr = disasm_str;
func = popcode->func;
if (func & Op_OE) {
u_int OE;
OE = extract_field(instr, 31 - 21, 1);
if (OE) {
APP_PSTRS("o");
}
func &= ~Op_OE;
}
switch (func & Op_LKM) {
case Op_Rc:
if (instr & 0x1) {
APP_PSTRS(".");
}
break;
case Op_AA:
if (instr & 0x2) {
APP_PSTRS("a");
loc = 0; /* Absolute address */
}
case Op_LK:
if (instr & 0x1) {
APP_PSTRS("l");
}
break;
default:
func &= ~Op_LKM;
}
APP_PSTRS("\t");
/* XXX: special cases here, out of flags in a 32bit word. */
if (strcmp(popcode->name, "wrteei") == 0) {
int E;
E = extract_field(instr, 31 - 16, 5);
APP_PSTR("%d", E);
return;
}
/* XXX: end of special cases here. */
if ((func & Op_FM) == Op_FM) {
u_int FM;
FM = extract_field(instr, 31 - 10, 8);
APP_PSTR("%d, ", FM);
func &= ~Op_FM;
}
if (func & Op_D) { /* Op_ST is the same */
u_int D;
D = extract_field(instr, 31 - 10, 5);
APP_PSTR("r%d, ", D);
func &= ~Op_D;
}
if (func & Op_crbD) {
u_int crbD;
crbD = extract_field(instr, 31 - 10, 5);
APP_PSTR("crb%d, ", crbD);
func &= ~Op_crbD;
}
if (func & Op_crfD) {
u_int crfD;
crfD = extract_field(instr, 31 - 8, 3);
APP_PSTR("crf%d, ", crfD);
func &= ~Op_crfD;
}
if (func & Op_L) {
u_int L;
L = extract_field(instr, 31 - 10, 1);
if (L) {
APP_PSTRS("L, ");
}
func &= ~Op_L;
}
if (func & Op_TO) {
u_int TO;
TO = extract_field(instr, 31 - 10, 1);
APP_PSTR("%d, ", TO);
func &= ~Op_TO;
}
if (func & Op_crfS) {
u_int crfS;
crfS = extract_field(instr, 31 - 13, 3);
APP_PSTR("%d, ", crfS);
func &= ~Op_crfS;
}
if (func & Op_BO) {
u_int BO;
BO = extract_field(instr, 31 - 10, 5);
APP_PSTR("%d, ", BO);
func &= ~Op_BO;
}
if (func & Op_A) {
u_int A;
A = extract_field(instr, 31 - 15, 5);
APP_PSTR("r%d, ", A);
func &= ~Op_A;
}
if (func & Op_S) {
u_int D;
D = extract_field(instr, 31 - 10, 5);
APP_PSTR("r%d, ", D);
func &= ~Op_S;
}
if (func & Op_B) {
u_int B;
B = extract_field(instr, 31 - 20, 5);
APP_PSTR("r%d, ", B);
func &= ~Op_B;
}
if (func & Op_C) {
u_int C;
C = extract_field(instr, 31 - 25, 5);
APP_PSTR("r%d, ", C);
func &= ~Op_C;
}
if (func & Op_BI) {
u_int BI;
BI = extract_field(instr, 31 - 15, 5);
APP_PSTR("%d, ", BI);
func &= ~Op_BI;
}
if (func & Op_crbA) {
u_int crbA;
crbA = extract_field(instr, 31 - 15, 5);
APP_PSTR("%d, ", crbA);
func &= ~Op_crbA;
}
if (func & Op_crbB) {
u_int crbB;
crbB = extract_field(instr, 31 - 20, 5);
APP_PSTR("%d, ", crbB);
func &= ~Op_crbB;
}
if (func & Op_CRM) {
u_int CRM;
CRM = extract_field(instr, 31 - 19, 8);
APP_PSTR("0x%x, ", CRM);
func &= ~Op_CRM;
}
if (func & Op_LI) {
int LI;
LI = extract_field(instr, 31 - 29, 24);
/* Need to sign extend and shift up 2, then add addr */
LI = LI << 8;
LI = LI >> 6;
LI += loc;
db_symstr(pstr, slen, LI, DB_STGY_ANY);
ADD_LEN(strlen(pstr));
func &= ~Op_LI;
}
switch (func & Op_SIMM) {
u_int IMM;
case Op_SIMM: /* same as Op_d */
IMM = extract_field(instr, 31 - 31, 16);
if (IMM & 0x8000) {
APP_PSTRS("-");
IMM = 0x10000-IMM;
}
func &= ~Op_SIMM;
goto common;
case Op_UIMM:
IMM = extract_field(instr, 31 - 31, 16);
func &= ~Op_UIMM;
goto common;
common:
APP_PSTR("0x%x", IMM);
break;
default:
;
}
if (func & Op_BD) {
u_int BD;
BD = extract_field(instr, 31 - 29, 14);
APP_PSTR("0x%x, ", BD);
func &= ~Op_BD;
}
if (func & Op_ds) {
u_int ds;
ds = extract_field(instr, 31 - 29, 14) << 2;
APP_PSTR("0x%x, ", ds);
func &= ~Op_ds;
}
if (func & Op_spr) {
u_int spr;
u_int sprl;
u_int sprh;
const struct specialreg *regs;
int i;
sprl = extract_field(instr, 31 - 15, 5);
sprh = extract_field(instr, 31 - 20, 5);
spr = sprh << 5 | sprl;
/* ugly hack - out of bitfields in the function mask */
if (popcode->name[2] == 'd') /* m.Dcr */
regs = dcrregs;
else
regs = sprregs;
for (i = 0; regs[i].name != NULL; i++)
if (spr == regs[i].reg)
break;
if (regs[i].name == NULL)
APP_PSTR("[unknown special reg (%d)]", spr);
else
APP_PSTR("%s", regs[i].name);
func &= ~Op_spr;
}
if (func & Op_me) {
u_int me, mel, meh;
mel = extract_field(instr, 31 - 25, 4);
meh = extract_field(instr, 31 - 26, 1);
me = meh << 4 | mel;
APP_PSTR(", 0x%x", me);
func &= ~Op_me;
}
if ((func & Op_SH) && (func & Op_sh_mb_sh)) {
u_int SH;
SH = extract_field(instr, 31 - 20, 5);
APP_PSTR(", %d", SH);
}
if ((func & Op_MB) && (func & Op_sh_mb_sh)) {
u_int MB;
u_int ME;
MB = extract_field(instr, 31 - 25, 5);
APP_PSTR(", %d", MB);
ME = extract_field(instr, 31 - 30, 5);
APP_PSTR(", %d", ME);
}
if ((func & Op_sh) && ! (func & Op_sh_mb_sh)) {
u_int sh, shl, shh;
shl = extract_field(instr, 31 - 19, 4);
shh = extract_field(instr, 31 - 20, 1);
sh = shh << 4 | shl;
APP_PSTR(", %d", sh);
}
if ((func & Op_mb) && ! (func & Op_sh_mb_sh)) {
u_int mb, mbl, mbh;
mbl = extract_field(instr, 31 - 25, 4);
mbh = extract_field(instr, 31 - 26, 1);
mb = mbh << 4 | mbl;
APP_PSTR(", %d", mb);
}
if ((func & Op_me) && ! (func & Op_sh_mb_sh)) {
u_int me, mel, meh;
mel = extract_field(instr, 31 - 25, 4);
meh = extract_field(instr, 31 - 26, 1);
me = meh << 4 | mel;
APP_PSTR(", %d", me);
}
if (func & Op_tbr) {
u_int tbr;
u_int tbrl;
u_int tbrh;
const char *reg;
tbrl = extract_field(instr, 31 - 15, 5);
tbrh = extract_field(instr, 31 - 20, 5);
tbr = tbrh << 5 | tbrl;
switch (tbr) {
case 268:
reg = "tbl";
break;
case 269:
reg = "tbu";
break;
default:
reg = 0;
}
if (reg == 0)
APP_PSTR(", [unknown tbr %d ]", tbr);
else
APP_PSTR(", %s", reg);
func &= ~Op_tbr;
}
if (func & Op_SR) {
u_int SR;
SR = extract_field(instr, 31 - 15, 3);
APP_PSTR(", sr%d", SR);
func &= ~Op_SR;
}
if (func & Op_NB) {
u_int NB;
NB = extract_field(instr, 31 - 20, 5);
if (NB == 0)
NB = 32;
APP_PSTR(", %d", NB);
func &= ~Op_SR;
}
if (func & Op_IMM) {
u_int IMM;
IMM = extract_field(instr, 31 - 19, 4);
APP_PSTR(", %d", IMM);
func &= ~Op_SR;
}
#undef ADD_LEN
#undef APP_PSTR
#undef APP_PSTRS
}
void
op_base(instr_t instr, vaddr_t loc)
{
dis_ppc(opcodes, instr, loc);
}
void
op_cl_x13(instr_t instr, vaddr_t loc)
{
dis_ppc(opcodes_13, instr, loc);
}
void
op_cl_x1e(instr_t instr, vaddr_t loc)
{
dis_ppc(opcodes_1e, instr, loc);
}
void
op_cl_x1f(instr_t instr, vaddr_t loc)
{
dis_ppc(opcodes_1f, instr, loc);
}
void
op_cl_x3a(instr_t instr, vaddr_t loc)
{
dis_ppc(opcodes_3a, instr, loc);
}
void
op_cl_x3b(instr_t instr, vaddr_t loc)
{
dis_ppc(opcodes_3b, instr, loc);
}
void
op_cl_x3e(instr_t instr, vaddr_t loc)
{
dis_ppc(opcodes_3e, instr, loc);
}
void
op_cl_x3f(instr_t instr, vaddr_t loc)
{
dis_ppc(opcodes_3f, instr, loc);
}
void
dis_ppc(const struct opcode *opcodeset, instr_t instr, vaddr_t loc)
{
const struct opcode *op;
int found = 0;
int i;
char disasm_str[80];
for (i = 0, op = &opcodeset[0];
found == 0 && op->mask != 0;
i++, op = &opcodeset[i]) {
if ((instr & op->mask) == op->code) {
found = 1;
disasm_fields(op, instr, loc, disasm_str,
sizeof disasm_str);
db_printf("%s%s\n", op->name, disasm_str);
return;
}
}
op_ill(instr, loc);
}
db_addr_t
db_disasm(db_addr_t loc, bool extended)
{
int class;
instr_t opcode;
opcode = *(instr_t *)(loc);
class = opcode >> 26;
(opcodes_base[class])(opcode, loc);
return (loc + 4);
}
vaddr_t opc_disasm(vaddr_t loc, int);
vaddr_t
opc_disasm(vaddr_t loc, int xin)
{
int class;
instr_t opcode;
opcode = xin;
class = opcode >> 26;
(opcodes_base[class])(opcode, loc);
return (loc + 4);
}