The dh_alias redirect is intended to handle TCG types as distinguished
from C types. TCG does not distinguish signed int from unsigned int,
because they are the same size. However, we need to retain this
distinction for dh_typecode, lest we fail to extend abi types properly
for the host call parameters.
This bug was detected when running the 'arm' emulator on an s390
system. The s390 uses TCG_TARGET_EXTEND_ARGS which triggers code
in tcg_gen_callN to extend 32 bit values to 64 bits; the incorrect
sign data in the typemask for each argument caused the values to be
extended as unsigned values.
This simple program exhibits the problem:
static volatile int num = -9;
static volatile int den = -5;
int main(void)
{
int quo = num / den;
printf("num %d den %d quo %d\n", num, den, quo);
exit(0);
}
When run on the broken qemu, this results in:
num -9 den -5 quo 0
The correct result is:
num -9 den -5 quo 1
Fixes:
|
||
|---|---|---|
| .. | ||
| user | ||
| address-spaces.h | ||
| confidential-guest-support.h | ||
| cpu-all.h | ||
| cpu-common.h | ||
| cpu-defs.h | ||
| cpu_ldst.h | ||
| cputlb.h | ||
| exec-all.h | ||
| gdbstub.h | ||
| gen-icount.h | ||
| helper-gen.h | ||
| helper-head.h | ||
| helper-proto.h | ||
| helper-tcg.h | ||
| hwaddr.h | ||
| ioport.h | ||
| log.h | ||
| memattrs.h | ||
| memop.h | ||
| memopidx.h | ||
| memory-internal.h | ||
| memory.h | ||
| memory_ldst.h.inc | ||
| memory_ldst_cached.h.inc | ||
| memory_ldst_phys.h.inc | ||
| page-vary.h | ||
| plugin-gen.h | ||
| poison.h | ||
| ram_addr.h | ||
| ramblock.h | ||
| ramlist.h | ||
| softmmu-semi.h | ||
| target_page.h | ||
| translate-all.h | ||
| translator.h | ||