https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113723
Bug ID: 113723
Summary: -freorder-blocks-and-partition emits bogus asm
directives on aarch64
Product: gcc
Version: 14.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: target
Assignee: unassigned at gcc dot gnu.org
Reporter: redbeard0531 at gmail dot com
Target Milestone: ---
It tries to subtract labels across the function split which the assembler
rejects. At the very least it does this when generating a switch jump table,
but there may be other cases.
https://www.godbolt.org/z/Ynh1zzY4a
Repro with -O3 -freorder-blocks-and-partition:
[[gnu::cold]]void cold();
template<int i> void f();
#define GENERATE_CASE case __COUNTER__: f<__COUNTER__>(); break
void test(int i) {
switch(i) {
case 1: cold(); break;
GENERATE_CASE;
GENERATE_CASE;
GENERATE_CASE;
GENERATE_CASE;
GENERATE_CASE;
GENERATE_CASE;
GENERATE_CASE;
GENERATE_CASE;
GENERATE_CASE;
GENERATE_CASE;
}
}
test(int):
cmp w0, 18
bls .L17
.L1:
ret
.L17:
adrp x1, .L4
add x1, x1, :lo12:.L4
ldrb w1, [x1,w0,uxtw]
adr x0, .Lrtx4
add x1, x0, w1, sxtb #2
br x1
.Lrtx4:
.L4:
.byte (.L14 - .Lrtx4) / 4
.byte (.L13 - .Lrtx4) / 4 // <<<< THIS IS THE BAD ONE
.byte (.L12 - .Lrtx4) / 4
...
test(int) [clone .cold]:
.L13:
b cold()
/tmp/cck05x4u.s: Assembler messages:
/tmp/cck05x4u.s:48: Error: invalid operands (.text.unlikely and .text sections)
for `-'
Compiler returned: 1
I've repro'd on 11,12, and trunk.
