Files
sigmaker-ida/idasdk76/module/tms320c54/emu.cpp
2021-10-31 21:20:46 +02:00

436 lines
12 KiB
C++

/*
* Interactive disassembler (IDA).
* Copyright (c) 1990-99 by Ilfak Guilfanov.
* ALL RIGHTS RESERVED.
* E-mail: ig@datarescue.com
*
*
*/
#include "tms320c54.hpp"
#include <segregs.hpp>
#include <frame.hpp>
//------------------------------------------------------------------------
ea_t calc_code_mem(const insn_t &insn, ea_t ea, bool is_near)
{
ea_t rv;
if ( is_near )
{
sel_t xpc = get_sreg(insn.ea, XPC);
if ( xpc == BADSEL )
xpc = 0;
rv = ((xpc & 0x7F) << 16) | (ea & 0xFFFF);
}
else
{
rv = to_ea(insn.cs, ea);
}
return use_mapping(rv);
}
//------------------------------------------------------------------------
ea_t tms320c54_t::calc_data_mem(const insn_t &insn, ea_t ea, bool is_mem) const
{
ea_t rv;
if ( is_mem )
{
sel_t dp = get_sreg(insn.ea, DP);
if ( dp == BADSEL )
return BADSEL;
rv = ((dp & 0x1FF) << 7) | (ea & 0x7F);
}
else
{
rv = ea;
}
rv += dataseg;
return use_mapping(rv);
}
//----------------------------------------------------------------------
regnum_t tms320c54_t::get_mapped_register(ea_t ea) const
{
if ( idpflags & TMS320C54_MMR )
{
switch ( ea-dataseg )
{
case 0x00: return IMR;
case 0x01: return IFR;
case 0x06: return ST0;
case 0x07: return ST1;
case 0x08: return AL;
case 0x09: return AH;
case 0x0A: return AG;
case 0x0B: return BL;
case 0x0C: return BH;
case 0x0D: return BG;
case 0x0E: return T;
case 0x0F: return TRN;
case 0x10: return AR0;
case 0x11: return AR1;
case 0x12: return AR2;
case 0x13: return AR3;
case 0x14: return AR4;
case 0x15: return AR5;
case 0x16: return AR6;
case 0x17: return AR7;
case 0x18: return SP;
case 0x19: return BK;
case 0x1A: return BRC;
case 0x1B: return RSA;
case 0x1C: return REA;
case 0x1D: return PMST;
case 0x1E: return XPC;
default: return rnone;
}
}
else
return rnone;
}
//----------------------------------------------------------------------
static void process_imm(const insn_t &insn, const op_t &x, flags_t F)
{
set_immd(insn.ea);
if ( is_defarg(F, x.n) )
return; // if already defined by user
switch ( insn.itype )
{
case TMS320C54_cmpm:
case TMS320C54_bitf:
case TMS320C54_andm:
case TMS320C54_orm:
case TMS320C54_xorm:
case TMS320C54_addm:
case TMS320C54_st:
case TMS320C54_stm:
case TMS320C54_rpt:
case TMS320C54_ld3:
case TMS320C54_mpy2:
case TMS320C54_rptz:
case TMS320C54_add3:
case TMS320C54_sub3:
case TMS320C54_and3:
case TMS320C54_or3:
case TMS320C54_xor3:
case TMS320C54_mac2:
op_num(insn.ea, x.n);
}
}
//----------------------------------------------------------------------
void tms320c54_t::handle_operand(const insn_t &insn, const op_t &x, flags_t F, bool use)
{
switch ( x.type )
{
case o_bit:
case o_reg:
case o_cond8:
case o_cond2:
return;
case o_near:
case o_far:
{
if ( insn.itype != TMS320C54_rptb && insn.itype != TMS320C54_rptbd )
{
cref_t ftype = fl_JN;
ea_t ea = calc_code_mem(insn, x.addr, x.type == o_near);
if ( has_insn_feature(insn.itype, CF_CALL) )
{
if ( !func_does_return(ea) )
flow = false;
ftype = fl_CN;
}
#ifndef TMS320C54_NO_NAME_NO_REF
if ( x.dtype == dt_byte )
insn.add_dref(ea, x.offb, dr_R);
else
insn.add_cref(ea, x.offb, ftype);
#endif
}
#ifndef TMS320C54_NO_NAME_NO_REF
else // evaluate RPTB[D] loops as dref
insn.add_dref(calc_code_mem(insn, x.addr), x.offb, dr_I);
#endif
}
break;
case o_imm:
QASSERT(10113, use);
process_imm(insn, x, F);
#ifndef TMS320C54_NO_NAME_NO_REF
if ( op_adds_xrefs(F, x.n) )
insn.add_off_drefs(x, dr_O, x.Signed ? OOF_SIGNED : 0);
#endif
break;
case o_mem:
case o_farmem:
case o_mmr:
{
ea_t ea = calc_data_mem(insn, x.addr, x.type == o_mem);
if ( ea != BADADDR )
{
#ifndef TMS320C54_NO_NAME_NO_REF
insn.add_dref(ea, x.offb, use ? dr_R : dr_W);
#endif
insn.create_op_data(ea, x);
}
}
break;
case o_local: // local variables
if ( may_create_stkvars()
&& (get_func(insn.ea) != NULL)
&& insn.create_stkvar(x, x.addr, STKVAR_VALID_SIZE) )
{
op_stkvar(insn.ea, x.n);
}
break;
case o_displ:
set_immd(insn.ea);
break;
default:
warning("interr: emu2 address:%a operand:%d type:%d", insn.ea, x.n, x.type);
}
}
//----------------------------------------------------------------------
// is the previous instruction a delayed jump ?
//
// The following array shows all delayed instructions (xxx[D])
// who are required to always stop.
//
// Z = 1 : delay instruction bit
//
// BRANCH INSTRUCTIONS
//
// TMS320C54_bd, // Branch Unconditionally 1111 00Z0 0111 0011 16-bit constant B[D] pmad
// TMS320C54_baccd, // Branch to Location Specified by Accumulator 1111 01ZS 1110 0010 BACC[D] src
// TMS320C54_fbd, // Far Branch Unconditionally 1111 10Z0 1 7bit constant=pmad(22-16) 16-bit constant=pmad(15-0) FB[D] extpmad
// TMS320C54_fbaccd, // Far Branch to Location Specified by Accumulator 1111 01ZS 1110 0110 FBACC[D] src
//
// RETURN INSTRUCTIONS
//
// TMS320C54_fretd, // Far Return 1111 01Z0 1110 0100 FRET[D]
// TMS320C54_freted, // Enable Interrupts and Far Return From Interrupt 1111 01Z0 1110 0101 FRETE[D]
// TMS320C54_retd, // Return 1111 11Z0 0000 0000 RET[D]
// TMS320C54_reted, // Enable Interrupts and Return From Interrupt 1111 01Z0 1110 1011 RETE[D]
// TMS320C54_retfd, // Enable Interrupts and Fast Return From Interrupt 1111 01Z0 1001 1011 RETF[D]
static bool delayed_stop(const insn_t &insn, flags_t F)
{
if ( !is_flow(F) )
return false;
if ( insn.size == 0 || insn.size > 2 )
return false;
int sub = 2 - insn.size; // backward offset to skip the previous 1-word instruction in the case of 2 consecutive 1-word instructions
// first, we analyze 1-word instructions
ea_t ea = insn.ea - sub - 1;
if ( is_code(get_flags(ea)) )
{
int code = get_wide_byte(ea); // get the instruction word
switch ( code )
{
case 0xF6E2: // TMS320C54_baccd, // Branch to Location Specified by Accumulator 1111 01ZS 1110 0010 BACC[D] src
case 0xF7E2:
case 0xF6E6: // TMS320C54_fbaccd, // Far Branch to Location Specified by Accumulator 1111 01ZS 1110 0110 FBACC[D] src
case 0xF7E6:
case 0xF6E4: // TMS320C54_fretd, // Far Return 1111 01Z0 1110 0100 FRET[D]
case 0xF6E5: // TMS320C54_freted, // Enable Interrupts and Far Return From Interrupt 1111 01Z0 1110 0101 FRETE[D]
case 0xFE00: // TMS320C54_retd, // Return 1111 11Z0 0000 0000 RET[D]
case 0xF6EB: // TMS320C54_reted, // Enable Interrupts and Return From Interrupt 1111 01Z0 1110 1011 RETE[D]
case 0xF69B: // TMS320C54_retfd, // Enable Interrupts and Fast Return From Interrupt 1111 01Z0 1001 1011 RETF[D]
return true;
}
}
// else, we analyze 2-word instructions
ea = insn.ea - sub - 2;
if ( is_code(get_flags(ea)) )
{
int code = get_wide_byte(ea); // get the first instruction word
if ( code == 0xF273 // TMS320C54_bd, // Branch Unconditionally 1111 00Z0 0111 0011 16-bit constant B[D] pmad
|| (code & 0xFF80) == 0xFA80 ) // TMS320C54_fbd, // Far Branch Unconditionally 1111 10Z0 1 7bit constant=pmad(22-16) 16-bit constant=pmad(15-0) FB[D] extpmad
{
return true;
}
}
return false;
}
//----------------------------------------------------------------------
bool is_basic_block_end(const insn_t &insn)
{
flags_t F = get_flags(insn.ea);
if ( delayed_stop(insn, F) )
return true;
return !is_flow(get_flags(insn.ea+insn.size));
}
//----------------------------------------------------------------------
static bool add_stkpnt(const insn_t &insn, sval_t delta)
{
func_t *pfn = get_func(insn.ea);
if ( pfn == NULL )
return false;
return add_auto_stkpnt(pfn, insn.ea+insn.size, delta);
}
//----------------------------------------------------------------------
static void trace_sp(const insn_t &insn)
{
// trace SP changes
switch ( insn.itype )
{
case TMS320C54_fret:
case TMS320C54_fretd:
case TMS320C54_frete:
case TMS320C54_freted:
add_stkpnt(insn, 2);
break;
case TMS320C54_ret:
case TMS320C54_retd:
case TMS320C54_rete:
case TMS320C54_reted:
case TMS320C54_retf:
case TMS320C54_retfd:
add_stkpnt(insn, 1);
break;
case TMS320C54_frame:
add_stkpnt(insn, insn.Op1.value);
break;
case TMS320C54_popd:
case TMS320C54_popm:
add_stkpnt(insn, 1);
break;
case TMS320C54_pshd:
case TMS320C54_pshm:
add_stkpnt(insn, -1);
break;
}
}
//----------------------------------------------------------------------
int tms320c54_t::emu(const insn_t &insn)
{
uint32 feature = insn.get_canon_feature(ph);
flow = (feature & CF_STOP) == 0;
flags_t F = get_flags(insn.ea);
if ( feature & CF_USE1 ) handle_operand(insn, insn.Op1, F, true);
if ( feature & CF_USE2 ) handle_operand(insn, insn.Op2, F, true);
if ( feature & CF_USE3 ) handle_operand(insn, insn.Op3, F, true);
if ( feature & CF_CHG1 ) handle_operand(insn, insn.Op1, F, false);
if ( feature & CF_CHG2 ) handle_operand(insn, insn.Op2, F, false);
if ( feature & CF_CHG3 ) handle_operand(insn, insn.Op3, F, false);
// check for CPL changes
if ( (insn.itype == TMS320C54_rsbx1 || insn.itype == TMS320C54_ssbx1)
&& insn.Op1.type == o_reg && insn.Op1.reg == CPL )
{
int value = insn.itype == TMS320C54_rsbx1 ? 0 : 1;
split_sreg_range(get_item_end(insn.ea), CPL, value, SR_auto);
}
// check for DP changes
if ( insn.itype == TMS320C54_ld2
&& insn.Op1.type == o_imm
&& insn.Op1.dtype == dt_byte
&& insn.Op2.type == o_reg
&& insn.Op2.reg == DP )
{
split_sreg_range(get_item_end(insn.ea), DP, insn.Op1.value & 0x1FF, SR_auto);
}
// determine if the next instruction should be executed
if ( segtype(insn.ea) == SEG_XTRN )
flow = false;
if ( flow && delayed_stop(insn, F) )
flow = false;
if ( flow )
add_cref(insn.ea, insn.ea+insn.size, fl_F);
if ( may_trace_sp() )
{
if ( !flow )
recalc_spd(insn.ea); // recalculate SP register for the next insn
else
trace_sp(insn);
}
return 1;
}
//----------------------------------------------------------------------
bool tms320c54_t::create_func_frame(func_t *pfn) const
{
if ( pfn != NULL )
{
if ( pfn->frame == BADNODE )
{
insn_t insn;
int regsize = 0;
ea_t ea = pfn->start_ea;
while ( ea < pfn->end_ea ) // check for register pushs
{
if ( decode_insn(&insn, ea) < 1 )
break;
if ( insn.itype != TMS320C54_pshm )
break;
if ( insn.Op1.type != o_mem && insn.Op1.type != o_mmr )
break;
if ( get_mapped_register(insn.Op1.addr) == rnone )
break;
regsize++;
ea += insn.size;
}
int localsize = 0;
while ( ea < pfn->end_ea ) // check for frame creation
{
if ( insn.itype == TMS320C54_frame && insn.Op1.type == o_imm )
{
localsize = -(int)insn.Op1.value;
break;
}
ea += insn.size;
if ( decode_insn(&insn, ea) < 1 )
break;
}
add_frame(pfn, localsize+regsize, 0, 0);
}
}
return 0;
}
//----------------------------------------------------------------------
int idaapi tms_get_frame_retsize(const func_t * /*pfn*/)
{
return 1; // 1 'byte' for the return address
}
//----------------------------------------------------------------------
int idaapi is_align_insn(ea_t ea)
{
insn_t insn;
if ( decode_insn(&insn, ea) < 1 )
return 0;
switch ( insn.itype )
{
case TMS320C54_nop:
break;
default:
return 0;
}
return insn.size;
}