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| author | Richard Henderson <richard.henderson@linaro.org> | 2022-02-16 20:06:22 -0500 |
|---|---|---|
| committer | Richard Henderson <richard.henderson@linaro.org> | 2022-02-28 08:04:06 -1000 |
| commit | 8929906e212cbe606e361cbd32917dcbe5bb6dd0 (patch) | |
| tree | 4acc52416554ce423d8cb93f7cc303affa7303a8 /target/m68k/helper.h | |
| parent | 00483d386901173e84c7965f9f0d678791a75e01 (diff) | |
| download | qemu-8929906e212cbe606e361cbd32917dcbe5bb6dd0.zip qemu-8929906e212cbe606e361cbd32917dcbe5bb6dd0.tar.gz qemu-8929906e212cbe606e361cbd32917dcbe5bb6dd0.tar.bz2 | |
tcg: Remove dh_alias indirection for dh_typecode
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: 7319d83a735 ("tcg: Combine dh_is_64bit and dh_is_signed to dh_typecode")
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/876
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reported-by: Christian Ehrhardt <christian.ehrhardt@canonical.com>
Tested-by: Christian Ehrhardt <christian.ehrhardt@canonical.com>
Tested-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Diffstat (limited to 'target/m68k/helper.h')
| -rw-r--r-- | target/m68k/helper.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/target/m68k/helper.h b/target/m68k/helper.h index 9842eea..0a6b414 100644 --- a/target/m68k/helper.h +++ b/target/m68k/helper.h @@ -17,6 +17,7 @@ DEF_HELPER_4(cas2l_parallel, void, env, i32, i32, i32) #define dh_alias_fp ptr #define dh_ctype_fp FPReg * +#define dh_typecode_fp dh_typecode_ptr DEF_HELPER_3(exts32, void, env, fp, s32) DEF_HELPER_3(extf32, void, env, fp, f32) |