void asm_x86_cmp_i32_with_r32(asm_x86_t *as, int src_i32, int src_r32) {
if (SIGNED_FIT8(src_i32)) {
asm_x86_write_byte_2(as, OPCODE_CMP_I8_WITH_RM32, MODRM_R32(7) | MODRM_RM_REG | MODRM_RM_R32(src_r32));
asm_x86_write_byte_1(as, src_i32 & 0xff);
} else {
asm_x86_write_byte_2(as, OPCODE_CMP_I32_WITH_RM32, MODRM_R32(7) | MODRM_RM_REG | MODRM_RM_R32(src_r32));
asm_x86_write_word32(as, src_i32);
}
}
STATIC void asm_x86_add_i32_to_r32(asm_x86_t *as, int src_i32, int dest_r32) {
if (SIGNED_FIT8(src_i32)) {
asm_x86_write_byte_2(as, OPCODE_ADD_I8_TO_RM32, MODRM_R32(0) | MODRM_RM_REG | MODRM_RM_R32(dest_r32));
asm_x86_write_byte_1(as, src_i32 & 0xff);
} else {
asm_x86_write_byte_2(as, OPCODE_ADD_I32_TO_RM32, MODRM_R32(0) | MODRM_RM_REG | MODRM_RM_R32(dest_r32));
asm_x86_write_word32(as, src_i32);
}
}
STATIC void asm_x86_sub_r32_i32(asm_x86_t *as, int dest_r32, int src_i32) {
if (SIGNED_FIT8(src_i32)) {
// defaults to 32 bit operation
asm_x86_write_byte_2(as, OPCODE_SUB_I8_FROM_RM32, MODRM_R32(5) | MODRM_RM_REG | MODRM_RM_R32(dest_r32));
asm_x86_write_byte_1(as, src_i32 & 0xff);
} else {
// defaults to 32 bit operation
asm_x86_write_byte_2(as, OPCODE_SUB_I32_FROM_RM32, MODRM_R32(5) | MODRM_RM_REG | MODRM_RM_R32(dest_r32));
asm_x86_write_word32(as, src_i32);
}
}
STATIC void asm_x86_write_r32_disp(asm_x86_t *as, int r32, int disp_r32, int disp_offset) {
assert(disp_r32 != ASM_X86_REG_ESP);
if (disp_offset == 0 && disp_r32 != ASM_X86_REG_EBP) {
asm_x86_write_byte_1(as, MODRM_R32(r32) | MODRM_RM_DISP0 | MODRM_RM_R32(disp_r32));
} else if (SIGNED_FIT8(disp_offset)) {
asm_x86_write_byte_2(as, MODRM_R32(r32) | MODRM_RM_DISP8 | MODRM_RM_R32(disp_r32), IMM32_L0(disp_offset));
} else {
asm_x86_write_byte_1(as, MODRM_R32(r32) | MODRM_RM_DISP32 | MODRM_RM_R32(disp_r32));
asm_x86_write_word32(as, disp_offset);
}
}
void asm_x86_call_ind(asm_x86_t *as, void *ptr, mp_uint_t n_args, int temp_r32) {
// TODO align stack on 16-byte boundary before the call
assert(n_args <= 3);
if (n_args > 2) {
asm_x86_push_r32(as, ASM_X86_REG_ARG_3);
}
if (n_args > 1) {
asm_x86_push_r32(as, ASM_X86_REG_ARG_2);
}
if (n_args > 0) {
asm_x86_push_r32(as, ASM_X86_REG_ARG_1);
}
#ifdef __LP64__
// We wouldn't run x86 code on an x64 machine. This is here to enable
// testing of the x86 emitter only.
asm_x86_mov_i32_to_r32(as, (int32_t)(int64_t)ptr, temp_r32);
#else
// If we get here, sizeof(int) == sizeof(void*).
asm_x86_mov_i32_to_r32(as, (int32_t)ptr, temp_r32);
#endif
asm_x86_write_byte_2(as, OPCODE_CALL_RM32, MODRM_R32(2) | MODRM_RM_REG | MODRM_RM_R32(temp_r32));
// this reduces code size by 2 bytes per call, but doesn't seem to speed it up at all
/*
asm_x86_write_byte_1(as, OPCODE_CALL_REL32);
asm_x86_write_word32(as, ptr - (void*)(as->code_base + as->code_offset + 4));
*/
// the caller must clean up the stack
if (n_args > 0) {
asm_x86_add_i32_to_r32(as, WORD_SIZE * n_args, ASM_X86_REG_ESP);
}
}
void asm_x86_setcc_r8(asm_x86_t *as, mp_uint_t jcc_type, int dest_r8) {
asm_x86_write_byte_3(as, OPCODE_SETCC_RM8_A, OPCODE_SETCC_RM8_B | jcc_type, MODRM_R32(0) | MODRM_RM_REG | MODRM_RM_R32(dest_r8));
}
void asm_x86_test_r8_with_r8(asm_x86_t *as, int src_r32_a, int src_r32_b) {
// TODO implement for other registers
assert(src_r32_a == ASM_X86_REG_EAX);
assert(src_r32_b == ASM_X86_REG_EAX);
asm_x86_write_byte_2(as, OPCODE_TEST_R8_WITH_RM8, MODRM_R32(src_r32_a) | MODRM_RM_REG | MODRM_RM_R32(src_r32_b));
}
void asm_x86_cmp_r32_with_r32(asm_x86_t *as, int src_r32_a, int src_r32_b) {
asm_x86_write_byte_2(as, OPCODE_CMP_R32_WITH_RM32, MODRM_R32(src_r32_a) | MODRM_RM_REG | MODRM_RM_R32(src_r32_b));
}
void asm_x86_sar_r32_by_imm(asm_x86_t *as, int r32, int imm) {
asm_x86_write_byte_2(as, OPCODE_SAR_RM32_BY_I8, MODRM_R32(7) | MODRM_RM_REG | MODRM_RM_R32(r32));
asm_x86_write_byte_1(as, imm);
}
STATIC void asm_x86_generic_r32_r32(asm_x86_t *as, int dest_r32, int src_r32, int op) {
asm_x86_write_byte_2(as, op, MODRM_R32(src_r32) | MODRM_RM_REG | MODRM_RM_R32(dest_r32));
}
void asm_x86_mul_r32_r32(asm_x86_t *as, int dest_r32, int src_r32) {
// imul reg32, reg/mem32 -- 0x0f 0xaf /r
asm_x86_write_byte_3(as, 0x0f, 0xaf, MODRM_R32(dest_r32) | MODRM_RM_REG | MODRM_RM_R32(src_r32));
}