https://gcc.gnu.org/bugzilla/show_bug.cgi?id=123625
Bug ID: 123625
Summary: [14/15/16 Regression] AArch64: wrong code at -O3
Product: gcc
Version: 16.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: target
Assignee: unassigned at gcc dot gnu.org
Reporter: xxs_chy at outlook dot com
Target Milestone: ---
Testcase:
#include <stdint.h>
#include <stdio.h>
#define BS_VEC(type, num) type __attribute__((vector_size(num * sizeof(type))))
uint64_t BS_CHECKSUM, g_284;
struct U0
{
int16_t f0;
int64_t f2
} g_205;
int16_t g_8, func_2_BS_COND_1;
uint8_t g_9[2][1];
volatile struct U0 g_121[];
int64_t *g_565 = &g_284;
int main()
{
BS_VEC(int64_t, 16) BS_VAR_3 = { 1, 8096386231136, 9039249955151 };
uint64_t LOCAL_CHECKSUM = 0;
switch (func_2_BS_COND_1)
{
case 2: goto BS_LABEL_0;
case 4: goto BS_LABEL_0;
}
for (g_8 = 0; g_8 <= 0; g_8 += 1)
for (g_205.f2 = 0; g_205.f2 <= 1; g_205.f2 += 1)
{
if (g_9[g_205.f2][0])
BS_LABEL_0:
for (;;)
;
for (uint32_t BS_TEMP_371 = 0; BS_TEMP_371 < 16; BS_TEMP_371++)
LOCAL_CHECKSUM ^= BS_VAR_3[BS_TEMP_371] + 9
+ (LOCAL_CHECKSUM << 6) + LOCAL_CHECKSUM
>> (*g_565 |= g_121[0].f0);
BS_VAR_3 = (BS_VEC(int64_t, 16)){};
}
BS_CHECKSUM = LOCAL_CHECKSUM;
printf("BackSmith Checksum = 0x%016llx\n", BS_CHECKSUM);
}
Commands:
> aarch64-unknown-linux-musl-gcc -O1 -static a.c && qemu-aarch64 a.out
> aarch64-unknown-linux-musl-gcc -O3 -static a.c && qemu-aarch64 a.out
Output:
> BackSmith Checksum = 0x7237237237237237
> BackSmith Checksum = 0x302b03b33f237237
gcc version 16.0.1 20260114 (experimental)
