[BUG] Free GCC 4.9.2 illegal operand for VLE e_subfic instruction Posted on August 09, 2016 at 08:48
I just wanted to report a bug with the new free gcc 4.9.2. distributed in SPC5Studio 4. The compiler is apparently not aware of the special SCI8 format required by the e_subfic VLE instruction.
The following code example consistently exhibits the error for me:
1.
uint8_t illegal_value_test(uint16_t arg0) {
2.
3.
if
(arg0 <= 0x7FF)
4.
return
TRUE;
5.
else
6.
return
FALSE;
7.
8.
}
The important part is the comparison with
<= 0x7FF (or
< 0x800, doesn't matter), which will output the following asm:
5 .section .text.illegal_value_test,''axv'',@progbits
6 .align 1
7 .p2align 4,,15
8 .globl illegal_value_test
9 .type illegal_value_test, @function
10 illegal_value_test:
11 .LFB4:
12 .file 1 ''main.c''
13 .loc 1 22 0
14 .cfi_startproc
15 .LVL0:
16 .loc 1 29 0
17 ???? 1863B000 e_subfic %r3,%r3,2047
**** Error: illegal immediate value
18 ???? 70600000 e_li %r3,0
19 ???? 7C631914 adde %r3,%r3,%r3
20 .LVL1:
21 ???? 0004 se_blr
2
