diff options
Diffstat (limited to 'yjit_asm.c')
| -rw-r--r-- | yjit_asm.c | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/yjit_asm.c b/yjit_asm.c index 76fc3bf8db..da640e6d7d 100644 --- a/yjit_asm.c +++ b/yjit_asm.c @@ -1682,6 +1682,29 @@ void ud2(codeblock_t* cb) cb_write_bytes(cb, 2, 0x0F, 0x0B); } +/// xchg - Exchange Register/Memory with Register +void xchg(codeblock_t* cb, x86opnd_t rm_opnd, x86opnd_t r_opnd) +{ + assert (rm_opnd.num_bits == 64); + assert (r_opnd.num_bits == 64); + assert (rm_opnd.type == OPND_REG); + assert (r_opnd.type == OPND_REG); + + // If we're exchanging with RAX + if (rm_opnd.type == OPND_REG && rm_opnd.as.reg.reg_no == RAX.as.reg.reg_no) + { + // Write the REX byte + cb_write_rex(cb, rm_opnd.num_bits == 64, 0, 0, r_opnd.as.reg.reg_no); + + // Write the opcode and register number + cb_write_byte(cb, 0x90 + (r_opnd.as.reg.reg_no & 7)); + } + else + { + cb_write_rm(cb, rm_opnd.num_bits == 16, rm_opnd.num_bits == 64, r_opnd, rm_opnd, 0xFF, 1, 0x87); + } +} + /// xor - Exclusive bitwise OR void xor(codeblock_t* cb, x86opnd_t opnd0, x86opnd_t opnd1) { |