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No longer store sizes as bitfields

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On most (x86) processors, using bitfields is low than using slightly
more memory.
This commit is contained in:
Alexis Engelke
2019-01-13 16:19:41 +01:00
parent 5bdafbbcf0
commit 9d3f34bcc6
2 changed files with 15 additions and 37 deletions
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42
decode.c
View File

@@ -456,40 +456,19 @@ decode(const uint8_t* buffer, int len, DecodeMode mode, Instr* instr)
instr->segment = RI_DS;
}
uint8_t op_size_log = 0;
uint8_t op_size = 0;
if (desc->gp_size_8)
{
op_size_log = 1;
}
op_size = 1;
else if (mode == DECODE_64 && (prefixes & PREFIX_REXW))
{
op_size_log = 4;
}
op_size = 8;
else if (prefixes & PREFIX_OPSZ)
{
op_size_log = 2;
}
#if defined(ARCH_X86_64)
op_size = 2;
else if (mode == DECODE_64 && desc->gp_size_def64)
{
op_size_log = 4;
}
#endif
op_size = 8;
else
{
op_size_log = 3;
}
op_size = 4;
uint8_t op_size = (1 << op_size_log) >> 1;
if (UNLIKELY(desc->gp_instr_width))
{
instr->width = op_size_log;
}
else
{
instr->width = 0;
}
instr->op_size = UNLIKELY(desc->gp_instr_width) ? op_size : 0;
uint8_t vec_size = 16;
if (prefixes & PREFIX_VEXL)
@@ -498,11 +477,10 @@ decode(const uint8_t* buffer, int len, DecodeMode mode, Instr* instr)
}
// Compute address size.
uint8_t addr_size_log = mode == DECODE_64 ? 4 : 3;
uint8_t addr_size = mode == DECODE_64 ? 8 : 4;
if (prefixes & PREFIX_ADDRSZ)
addr_size_log -= 1;
instr->addr_size = addr_size_log;
uint8_t addr_size = (1 << addr_size_log) >> 1;
addr_size >>= 1;
instr->addr_size = addr_size;
uint8_t operand_sizes[4] = {
0, 1 << desc->gp_fixed_operand_size, op_size, vec_size

10
decode.h
View File

@@ -116,9 +116,9 @@ struct Instr
{
uint16_t type;
struct Operand operands[4];
uint8_t segment : 3;
uint8_t width : 3;
uint8_t addr_size : 2;
uint8_t segment;
uint8_t op_size;
uint8_t addr_size;
/**
* Encoded as 1 << (scale - 1) **or** no scaled register at all if zero.
@@ -137,8 +137,8 @@ struct Instr
typedef struct Instr Instr;
#define INSTR_SEGMENT(instr) ((instr)->segment)
#define INSTR_WIDTH(instr) ((1 << (instr)->width) >> 1)
#define INSTR_ADDRSZ(instr) ((1 << (instr)->addr_size) >> 1)
#define INSTR_WIDTH(instr) ((instr)->op_size)
#define INSTR_ADDRSZ(instr) ((instr)->addr_size)
#define INSTR_HAS_REP(instr) ((instr)->prefixes & PREFIX_REP)
#define INSTR_HAS_REPNZ(instr) ((instr)->prefixes & PREFIX_REPNZ)
#define INSTR_HAS_LOCK(instr) ((instr)->prefixes & PREFIX_LOCK)