https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84066
--- Comment #6 from igor.v.tsimbalist at intel dot com ---
(In reply to H.J. Lu from comment #5)
> (In reply to igor.v.tsimbalist from comment #4)
> > Created attachment 43280 [details]
> > updated patch
>
> - mem = gen_rtx_MEM (Pmode, plus_constant (Pmode, operands[0],
> - 3 * GET_MODE_SIZE (Pmode)));
> - reg_ssp = gen_reg_rtx (Pmode);
> + mem = gen_rtx_MEM (word_mode, plus_constant (Pmode, operands[0],
> + 3 * GET_MODE_SIZE (Pmode)));
>
> The first 3 fields are SP, FP and IP, which are in ptr_mode, not Pmode.
ok.
> /* Compute the numebr of frames to adjust. */
> + reg_adj = gen_rtx_SUBREG (Pmode, reg_ssp, 0);
>
> reg_ssp must be in word_mode, not in Pmode.
reg_ssp is word_mode. It's reg_adj that is Pmode (it's increment to shadow
stack).
> Please show the assembly outputs of __builtin_setjmp and __builtin_longjmp
> with the updated patch.
A snippet for __builtin_longjmp for -mx32
movl $0, %eax
rdsspq %rax
subq buf+12(%rip), %rax
je .L2
negl %eax
shrl $2, %eax
cmpl $255, %eax
jbe .L3
.L4:
incsspq %rax
subl $255, %eax
cmpl $255, %eax
ja .L4
.L3:
incsspq %rax
.L2:
Snippet for __builtin_setjmp for -mx32
movl %eax, buf(%rip)
movl $.L8, buf+4(%rip)
movl %esp, buf+8(%rip)
movl $0, %eax
rdsspq %rax
movq %rax, buf+12(%rip)
