hv: instr_emul: refine decode_prefixes to one exit point

Misra C requires Function must have only one return entry.

Tracked-On: #861
Signed-off-by: Li, Fei1 <fei1.li@intel.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>
This commit is contained in:
Li, Fei1 2019-01-11 08:12:02 +08:00 committed by wenlingz
parent 433a492a4e
commit 5e38e0ffd6

View File

@ -1698,16 +1698,16 @@ static bool segment_override(uint8_t x, enum cpu_reg_name *seg)
return override;
}
static int32_t decode_prefixes(struct instr_emul_vie *vie,
enum vm_cpu_mode cpu_mode, bool cs_d)
static int32_t decode_prefixes(struct instr_emul_vie *vie, enum vm_cpu_mode cpu_mode, bool cs_d)
{
uint8_t x, i;
int32_t ret = 0;
for (i = 0U; i < VIE_PREFIX_SIZE; i++) {
if (vie_peek(vie, &x) != 0) {
return -1;
}
ret = -1;
break;
} else {
if (x == 0x66U) {
vie->opsize_override = 1U;
} else if (x == 0x67U) {
@ -1724,7 +1724,9 @@ static int32_t decode_prefixes(struct instr_emul_vie *vie,
vie_advance(vie);
}
}
if (ret == 0) {
/*
* From section 2.2.1, "REX Prefixes", Intel SDM Vol 2:
* - Only one REX prefix is allowed per instruction.
@ -1767,7 +1769,9 @@ static int32_t decode_prefixes(struct instr_emul_vie *vie,
vie->addrsize = vie->addrsize_override != 0U ? 4U : 2U;
vie->opsize = vie->opsize_override != 0U ? 4U : 2U;
}
return 0;
}
return ret;
}
static int32_t decode_two_byte_opcode(struct instr_emul_vie *vie)