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ua.hpp File Reference

Functions that deal with the disassembling of program instructions. More...

Classes

class  op_t
 Operand of an instruction. More...
 
class  insn_t
 
union  value_union_t
 This union is used to pass byte values to various helper functions. More...
 
struct  value_union_t::dq_t
 
struct  value_union_t::dt_t
 
struct  value_union_t::d128_t
 
struct  outctx_base_t
 
struct  outctx_t
 
struct  macro_constructor_t
 Helper class for processor modules to build macro instructions. More...
 

Macros

#define OF_NO_BASE_DISP   0x80
 base displacement doesn't exist. More...
 
#define OF_OUTER_DISP   0x40
 outer displacement exists. More...
 
#define PACK_FORM_DEF   0x20
 packed factor defined. More...
 
#define OF_NUMBER   0x10
 the operand can be converted to a number only
 
#define OF_SHOW   0x08
 should the operand be displayed?
 
#define dt_byte   0
 8 bit integer
 
#define dt_word   1
 16 bit integer
 
#define dt_dword   2
 32 bit integer
 
#define dt_float   3
 4 byte floating point
 
#define dt_double   4
 8 byte floating point
 
#define dt_tbyte   5
 variable size ( processor_t::tbyte_size) floating point
 
#define dt_packreal   6
 packed real format for mc68040
 
#define dt_qword   7
 64 bit integer
 
#define dt_byte16   8
 128 bit integer
 
#define dt_code   9
 ptr to code (not used?)
 
#define dt_void   10
 none
 
#define dt_fword   11
 48 bit
 
#define dt_bitfild   12
 bit field (mc680x0)
 
#define dt_string   13
 pointer to asciiz string
 
#define dt_unicode   14
 pointer to unicode string
 
#define dt_ldbl   15
 long double (which may be different from tbyte)
 
#define dt_byte32   16
 256 bit integer
 
#define dt_byte64   17
 512 bit integer
 
#define dt_half   18
 2-byte floating point
 
#define DECLARE_INSN_HELPERS(decl)
 
#define Op1   ops[0]
 first operand
 
#define Op2   ops[1]
 second operand
 
#define Op3   ops[2]
 third operand
 
#define Op4   ops[3]
 fourth operand
 
#define Op5   ops[4]
 fifth operand
 
#define Op6   ops[5]
 sixth operand
 
#define Op7   ops[6]
 seventh operand
 
#define Op8   ops[7]
 eighth operand
 
#define INSN_MACRO   0x01
 macro instruction
 
#define INSN_MODMAC   0x02
 may modify the database to make room for the macro insn
 
#define INSN_64BIT   0x04
 belongs to 64bit segment?
 
#define CTXF_MAIN   0x00001
 
#define CTXF_MULTI   0x00002
 
#define CTXF_CODE   0x00004
 
#define CTXF_STACK   0x00008
 
#define CTXF_GEN_XREFS   0x00010
 
#define CTXF_XREF_STATE   0x00060
 
#define XREFSTATE_NONE   0x00
 
#define XREFSTATE_GO   0x20
 
#define XREFSTATE_DONE   0x40
 
#define CTXF_GEN_CMT   0x00080
 
#define CTXF_CMT_STATE   0x00300
 
#define COMMSTATE_NONE   0x000
 
#define COMMSTATE_GO   0x100
 
#define COMMSTATE_DONE   0x200
 
#define CTXF_VOIDS   0x00400
 
#define CTXF_NORMAL_LABEL   0x00800
 
#define CTXF_DEMANGLED_LABEL   0x01000
 
#define CTXF_LABEL_OK   0x02000
 
#define CTXF_DEMANGLED_OK   0x04000
 
#define CTXF_OVSTORE_PRNT   0x08000
 
#define CTXF_OUTCTX_T   0x10000
 
#define CTXF_DBLIND_OPND   0x20000
 
#define CTXF_BINOP_STATE   0xC0000
 
#define BINOPSTATE_NONE   0x00000
 
#define BINOPSTATE_GO   0x40000
 
#define BINOPSTATE_DONE   0x80000
 
#define CTXF_HIDDEN_ADDR   0x100000
 
#define CTXF_BIT_PREFIX   0x200000
 
#define OOF_SIGNMASK   0x0003
 sign symbol (+/-) output
 
#define OOFS_IFSIGN   0x0000
 output sign if needed
 
#define OOFS_NOSIGN   0x0001
 don't output sign, forbid the user to change the sign
 
#define OOFS_NEEDSIGN   0x0002
 always out sign (+-)
 
#define OOF_SIGNED   0x0004
 output as signed if < 0
 
#define OOF_NUMBER   0x0008
 always as a number
 
#define OOF_WIDTHMASK   0x0070
 width of value in bits
 
#define OOFW_IMM   0x0000
 take from x.dtype
 
#define OOFW_8   0x0010
 8 bit width
 
#define OOFW_16   0x0020
 16 bit width
 
#define OOFW_24   0x0030
 24 bit width
 
#define OOFW_32   0x0040
 32 bit width
 
#define OOFW_64   0x0050
 64 bit width
 
#define OOF_ADDR   0x0080
 output x.addr, otherwise x.value
 
#define OOF_OUTER   0x0100
 output outer operand
 
#define OOF_ZSTROFF   0x0200
 meaningful only if is_stroff(F); append a struct field name if the field offset is zero? if AFL_ZSTROFF is set, then this flag is ignored. More...
 
#define OOF_NOBNOT   0x0400
 prohibit use of binary not
 
#define OOF_SPACES   0x0800
 do not suppress leading spaces; currently works only for floating point numbers
 
#define OOF_ANYSERIAL   0x1000
 if enum: select first available serial
 
#define OOF_LZEROES   0x2000
 print leading zeroes
 
#define OOF_NO_LZEROES   0x4000
 do not print leading zeroes; if none of OOF_LZEROES and OOF_NO_LZEROES was specified, is_lzero() is used
 
#define DEFAULT_INDENT   0xFFFF
 
#define MAKELINE_NONE   0x00
 
#define MAKELINE_BINPREF   0x01
 
#define MAKELINE_VOID   0x02
 
#define MAKELINE_STACK   0x04
 
#define GH_PRINT_PROC   (1 << 0)
 
#define GH_PRINT_ASM   (1 << 1)
 
#define GH_PRINT_BYTESEX   (1 << 2)
 
#define GH_PRINT_HEADER   (1 << 3)
 
#define GH_BYTESEX_HAS_HIGHBYTE   (1 << 4)
 
#define GH_PRINT_PROC_AND_ASM   (GH_PRINT_PROC | GH_PRINT_ASM)
 
#define GH_PRINT_PROC_ASM_AND_BYTESEX   (GH_PRINT_PROC_AND_ASM | GH_PRINT_BYTESEX)
 
#define GH_PRINT_ALL   (GH_PRINT_PROC_ASM_AND_BYTESEX | GH_PRINT_HEADER)
 
#define GH_PRINT_ALL_BUT_BYTESEX   (GH_PRINT_PROC_AND_ASM | GH_PRINT_HEADER)
 
#define FCBF_CONT   0x00000001
 don't stop on decoding, or any other kind of error
 
#define FCBF_ERR_REPL   0x00000002
 in case of an error, use a CP_REPLCHAR instead of a hex representation of the problematic byte
 
#define FCBF_FF_LIT   0x00000004
 in case of codepoints == 0xFF, use it as-is (i.e., LATIN SMALL LETTER Y WITH DIAERESIS). More...
 
#define FCBF_DELIM   0x00000008
 add the 'ash'-specified delimiters around the generated data. More...
 
Emulator helpers
#define STKVAR_VALID_SIZE   0x0001
 x.dtype contains correct variable type (for insns like 'lea' this bit must be off). More...
 

Typedefs

typedef uchar optype_t
 see Operand types
 

Functions

 CASSERT (sizeof(insn_t)==216)
 
idaman size_t ida_export get_immvals (uval_t *out, ea_t ea, int n, flags64_t F, insn_t *cache=nullptr)
 Get immediate values at the specified address. More...
 
size_t get_printable_immvals (uval_t *out, ea_t ea, int n, flags64_t F, insn_t *cache=nullptr)
 Get immediate ready-to-print values at the specified address. More...
 
idaman int ida_export get_lookback (void)
 Number of instructions to look back. More...
 
idaman outctx_base_t *ida_export create_outctx (ea_t ea, flags64_t F=0, int suspop=0)
 Create a new output context. More...
 
idaman bool ida_export print_insn_mnem (qstring *out, ea_t ea)
 Print instruction mnemonics. More...
 
idaman bool ida_export format_charlit (qstring *out, const uchar **ptr, size_t size, uint32 flags=0, int encidx=0)
 Format character literal. More...
 
idaman bool ida_export print_fpval (char *buf, size_t bufsize, const void *v, int size)
 Print a floating point value. More...
 
idaman flags64_t ida_export get_dtype_flag (op_dtype_t dtype)
 Get flags for op_t::dtype field.
 
idaman size_t ida_export get_dtype_size (op_dtype_t dtype)
 Get size of opt_::dtype field.
 
idaman op_dtype_t ida_export get_dtype_by_size (asize_t size)
 Get op_t::dtype from size.
 
bool is_floating_dtype (op_dtype_t dtype)
 Is a floating type operand?
 
idaman int ida_export create_insn (ea_t ea, insn_t *out=nullptr)
 Create an instruction at the specified address. More...
 
idaman int ida_export decode_insn (insn_t *out, ea_t ea)
 Analyze the specified address and fill 'out'. More...
 
bool can_decode (ea_t ea)
 Can the bytes at address 'ea' be decoded as instruction? More...
 
idaman bool ida_export print_operand (qstring *out, ea_t ea, int n, int getn_flags=0, struct printop_t *newtype=nullptr)
 Generate text representation for operand #n. More...
 
idaman ea_t ida_export decode_prev_insn (insn_t *out, ea_t ea)
 Decode previous instruction if it exists, fill 'out'. More...
 
idaman ea_t ida_export decode_preceding_insn (insn_t *out, ea_t ea, bool *p_farref=nullptr)
 Decode preceding instruction in the execution flow. More...
 
idaman bool ida_export construct_macro2 (macro_constructor_t *_this, insn_t *insn, bool enable)
 
idaman int ida_export get_spoiled_reg (const insn_t &insn, const uint32 *regs, size_t n)
 Does the instruction spoil any register from 'regs'?. More...
 
Address translation

The following functions can be used by processor modules to map addresses from one region to another.

They are especially useful for microprocessors that map the same memory region to multiple address ranges or use memory bank switching. The user can use the following techniques to desribe address translations:

  • some processors support the segment transation feature. the user can specify the mapping in Edit, Segments, Change segment translation
  • the user can specify mapping for an individual direct call instruction by specifying it as an offset (Edit, Operand types, Offset)
  • specify the value of the data segment virtual register (ds). it will be used to calculate data addresses
idaman ea_t ida_export calc_dataseg (const insn_t &insn, int n=-1, int rgnum=-1)
 Get data segment for the instruction operand. More...
 
ea_t map_data_ea (const insn_t &insn, ea_t addr, int opnum=-1)
 Map a data address. More...
 
ea_t map_data_ea (const insn_t &insn, const op_t &op)
 
idaman ea_t ida_export map_code_ea (const insn_t &insn, ea_t addr, int opnum)
 Map a code address. More...
 
ea_t map_code_ea (const insn_t &insn, const op_t &op)
 
ea_t map_ea (const insn_t &insn, const op_t &op, bool iscode)
 
ea_t map_ea (const insn_t &insn, ea_t addr, int opnum, bool iscode)
 

Variables

const optype_t o_void = 0
 No Operand.
 
const optype_t o_reg = 1
 General Register (al,ax,es,ds...). More...
 
const optype_t o_mem = 2
 Direct Memory Reference (DATA). More...
 
const optype_t o_phrase = 3
 Memory Ref [Base Reg + Index Reg]. More...
 
const optype_t o_displ = 4
 Memory Ref [Base Reg + Index Reg + Displacement]. More...
 
const optype_t o_imm = 5
 Immediate Value. More...
 
const optype_t o_far = 6
 Immediate Far Address (CODE). More...
 
const optype_t o_near = 7
 Immediate Near Address (CODE). More...
 
const optype_t o_idpspec0 = 8
 processor specific type.
 
const optype_t o_idpspec1 = 9
 processor specific type.
 
const optype_t o_idpspec2 = 10
 processor specific type.
 
const optype_t o_idpspec3 = 11
 processor specific type.
 
const optype_t o_idpspec4 = 12
 processor specific type.
 
const optype_t o_idpspec5 = 13
 processor specific type. More...
 

Detailed Description

Functions that deal with the disassembling of program instructions.

There are 2 kinds of functions:

  • functions that are called from the kernel to disassemble an instruction. These functions call IDP module for it.
  • functions that are called from IDP module to disassemble an instruction. We will call them 'helper functions'.

Disassembly of an instruction is made in three steps:

  1. analysis: ana.cpp
  2. emulation: emu.cpp
  3. conversion to text: out.cpp

The kernel calls the IDP module to perform these steps. At first, the kernel always calls the analysis. The analyzer must decode the instruction and fill the insn_t instance that it receives through its callback. It must not change anything in the database.

The second step, the emulation, is called for each instruction. This step must make necessary changes to the database, plan analysis of subsequent instructions, track register values, memory contents, etc. Please keep in mind that the kernel may call the emulation step for any address in the program - there is no ordering of addresses. Usually, the emulation is called for consecutive addresses but this is not guaranteed.

The last step, conversion to text, is called each time an instruction is displayed on the screen. The kernel will always call the analysis step before calling the text conversion step. The emulation and the text conversion steps should use the information stored in the insn_t instance they receive. They should not access the bytes of the instruction and decode it again - this should only be done in the analysis step.

Macro Definition Documentation

◆ DECLARE_INSN_HELPERS

#define DECLARE_INSN_HELPERS (   decl)
Value:
decl uint8 ida_export insn_get_next_byte(insn_t *insn); \
decl uint16 ida_export insn_get_next_word(insn_t *insn); \
decl uint32 ida_export insn_get_next_dword(insn_t *insn); \
decl uint64 ida_export insn_get_next_qword(insn_t *insn); \
decl bool ida_export insn_create_op_data(const insn_t &insn, ea_t ea, int opoff, op_dtype_t dtype); \
decl void ida_export insn_add_cref(const insn_t &insn, ea_t to, int opoff, cref_t type); \
decl void ida_export insn_add_dref(const insn_t &insn, ea_t to, int opoff, dref_t type); \
decl ea_t ida_export insn_add_off_drefs(const insn_t &insn, const op_t &x, dref_t type, int outf); \
decl bool ida_export insn_create_stkvar(const insn_t &insn, const op_t &x, adiff_t v, int flags);
Definition: ua.hpp:354
Operand of an instruction.
Definition: ua.hpp:165
cref_t
CODE xref types.
Definition: xref.hpp:41
dref_t
DATA xref types.
Definition: xref.hpp:59
unsigned short uint16
unsigned 16 bit value
Definition: pro.h:345
unsigned int uint32
unsigned 32 bit value
Definition: pro.h:347
unsigned char uint8
unsigned 8 bit value
Definition: pro.h:343

Function Documentation

◆ get_immvals()

idaman size_t ida_export get_immvals ( uval_t out,
ea_t  ea,
int  n,
flags64_t  F,
insn_t cache = nullptr 
)

Get immediate values at the specified address.

This function decodes instruction at the specified address or inspects the data item. It finds immediate values and copies them to 'out'. This function will store the original value of the operands in 'out', unless the last bits of 'F' are "...0 11111111", in which case the transformed values (as needed for printing) will be stored instead.

Parameters
outarray of immediate values (at least 2*UA_MAXOP elements)
eaaddress to analyze
n0..UA_MAXOP-1 operand number, OPND_ALL all the operands
Fflags for the specified address
cacheoptional already decoded instruction or buffer for it. if the cache does not contain the decoded instruction, it will be updated (useful if we call get_immvals for the same address multiple times)
Returns
number of immediate values (0..2*UA_MAXOP)

◆ get_printable_immvals()

size_t get_printable_immvals ( uval_t out,
ea_t  ea,
int  n,
flags64_t  F,
insn_t cache = nullptr 
)
inline

Get immediate ready-to-print values at the specified address.

Parameters
outarray of immediate values (at least 2*UA_MAXOP elements)
eaaddress to analyze
n0..UA_MAXOP-1 operand number, OPND_ALL all the operands
Fflags for the specified address
cacheoptional already decoded instruction or buffer for it. if the cache does not contain the decoded instruction, it will be updated (useful if we call get_immvals for the same address multiple times)
Returns
number of immediate values (0..2*UA_MAXOP)

◆ get_lookback()

idaman int ida_export get_lookback ( void  )

Number of instructions to look back.

This variable is not used by the kernel. Its value may be specified in ida.cfg: LOOKBACK = <number>. IDP may use it as you like it. (TMS module uses it)

◆ calc_dataseg()

idaman ea_t ida_export calc_dataseg ( const insn_t insn,
int  n = -1,
int  rgnum = -1 
)

Get data segment for the instruction operand.

'opnum' and 'rgnum' are meaningful only if the processor has segment registers.

◆ map_data_ea()

ea_t map_data_ea ( const insn_t insn,
ea_t  addr,
int  opnum = -1 
)
inline

Map a data address.

Parameters
insnthe current instruction
addrthe referenced address to map
opnumoperand number

◆ map_code_ea()

idaman ea_t ida_export map_code_ea ( const insn_t insn,
ea_t  addr,
int  opnum 
)

Map a code address.

This function takes into account the segment translations.

Parameters
insnthe current instruction
addrthe referenced address to map
opnumoperand number

◆ create_outctx()

idaman outctx_base_t *ida_export create_outctx ( ea_t  ea,
flags64_t  F = 0,
int  suspop = 0 
)

Create a new output context.

To delete it, just use "delete pctx"

◆ print_insn_mnem()

idaman bool ida_export print_insn_mnem ( qstring out,
ea_t  ea 
)

Print instruction mnemonics.

Parameters
outoutput buffer
ealinear address of the instruction
Returns
success

◆ format_charlit()

idaman bool ida_export format_charlit ( qstring out,
const uchar **  ptr,
size_t  size,
uint32  flags = 0,
int  encidx = 0 
)

Format character literal.

Try and format 'size' bytes pointed to by '*ptr', as literal characters, using the 'encidx' encoding, and with the specified 'flags' directives.

By default, format_charlit() will fail and return an error, in any of the following cases:

  • a byte cannot be decoded using the specified (or default) encoding
  • a codepoint is < 0x20 (i.e., ' ')
  • a codepoint is present in 'ash.esccodes'
  • a codepoint is 0xFF
  • a codepoint is >= 0x80, and AS_NHIAS was specified in ash.flag The function can be told to keep going instead of bailing out, for any of these situations, by using one of the FCBF_*_OK flags.

If the function is told to proceed on a specific error, by default it will format the byte as a C-encoded byte value (i.e., '\xNN'), unless the corresponding FCBF_*_REPL flag is passed, in which case the problematic byte/codepoint will be replaced by the Unicode replacement character in the output.

Parameters
outoutput buffer (can be nullptr)
ptrpointer to pointer to bytes to print (will be advanced by the number of bytes that were successfully printed)
sizesize of input value in bytes
flagsformat flags
encidxthe 1 byte-per-unit encoding to use (or 0 to use the default 1 BPU encoding)
Returns
success

◆ print_fpval()

idaman bool ida_export print_fpval ( char *  buf,
size_t  bufsize,
const void *  v,
int  size 
)

Print a floating point value.

Parameters
bufoutput buffer. may be nullptr
bufsizesize of the output buffer
vfloating point value in processor native format
sizesize of the value in bytes
Returns
true ok
false can't represent as floating point number

◆ create_insn()

idaman int ida_export create_insn ( ea_t  ea,
insn_t out = nullptr 
)

Create an instruction at the specified address.

This function checks if an instruction is present at the specified address and will try to create one if there is none. It will fail if there is a data item or other items hindering the creation of the new instruction. This function will also fill the 'out' structure.

Parameters
ealinear address
outthe resulting instruction
Returns
the length of the instruction or 0

◆ decode_insn()

idaman int ida_export decode_insn ( insn_t out,
ea_t  ea 
)

Analyze the specified address and fill 'out'.

This function does not modify the database. It just tries to interpret the specified address as an instruction and fills the 'out' structure.

Parameters
outthe resulting instruction
ealinear address
Returns
the length of the (possible) instruction or 0

◆ can_decode()

bool can_decode ( ea_t  ea)
inline

Can the bytes at address 'ea' be decoded as instruction?

Parameters
ealinear address
Returns
whether or not the contents at that address could be a valid instruction

◆ print_operand()

idaman bool ida_export print_operand ( qstring out,
ea_t  ea,
int  n,
int  getn_flags = 0,
struct printop_t newtype = nullptr 
)

Generate text representation for operand #n.

This function will generate the text representation of the specified operand (includes color codes.)

Parameters
outoutput buffer
eathe item address (instruction or data)
n0..UA_MAXOP-1 operand number, meaningful only for instructions
getn_flagsName expression flags Currently only GETN_NODUMMY is accepted.
newtypeif specified, print the operand using the specified type
Returns
success

◆ decode_prev_insn()

idaman ea_t ida_export decode_prev_insn ( insn_t out,
ea_t  ea 
)

Decode previous instruction if it exists, fill 'out'.

Parameters
outthe resulting instruction
eathe address to decode the previous instruction from
Returns
the previous instruction address (BADADDR-no such insn)

◆ decode_preceding_insn()

idaman ea_t ida_export decode_preceding_insn ( insn_t out,
ea_t  ea,
bool *  p_farref = nullptr 
)

Decode preceding instruction in the execution flow.

Prefer far xrefs from addresses < the current to ordinary flows.

Parameters
outthe resulting instruction
eathe address to decode the preceding instruction from
p_farrefwill contain 'true' if followed an xref, false otherwise.
Returns
the preceding instruction address (BADADDR-no such insn) and 'out'.

◆ get_spoiled_reg()

idaman int ida_export get_spoiled_reg ( const insn_t insn,
const uint32 regs,
size_t  n 
)

Does the instruction spoil any register from 'regs'?.

This function checks the Instruction feature bits flags from the instructions array. Only o_reg operand types are consulted.

Parameters
insnthe instruction
regsarray with register indexes
nsize of 'regs'
Returns
index in the 'regs' array or -1