target/ppc: Fix bugs in VSX_CVT_FP_TO_INT and VSX_CVT_FP_TO_INT2 macros

The patch below fixes a bug in the VSX_CVT_FP_TO_INT and VSX_CVT_FP_TO_INT2
macros in target/ppc/fpu_helper.c where a non-NaN floating point value from the
source vector is incorrectly converted to 0, 0x80000000, or 0x8000000000000000
instead of the expected value if a preceding source floating point value from
the same source vector was a NaN.

The bug in the VSX_CVT_FP_TO_INT and VSX_CVT_FP_TO_INT2 macros in
target/ppc/fpu_helper.c was introduced with commit c3f24257e3.

This patch also adds a new vsx_f2i_nan test in tests/tcg/ppc64 that checks that
the VSX xvcvspsxws, xvcvspuxws, xvcvspsxds, xvcvspuxds, xvcvdpsxws, xvcvdpuxws,
xvcvdpsxds, and xvcvdpuxds instructions correctly convert non-NaN floating point
values to integer values if the source vector contains NaN floating point values.

Fixes: c3f24257e3 ("target/ppc: Clear fpstatus flags on helpers missing it")
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1941
Signed-off-by: John Platts <john_platts@hotmail.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
This commit is contained in:
John Platts 2023-11-10 18:41:42 +00:00 committed by Cédric Le Goater
parent 8bc5ae046d
commit d18b065286
3 changed files with 313 additions and 4 deletions

View file

@ -2880,20 +2880,22 @@ uint64_t helper_XSCVSPDPN(uint64_t xb)
#define VSX_CVT_FP_TO_INT(op, nels, stp, ttp, sfld, tfld, sfi, rnan) \
void helper_##op(CPUPPCState *env, ppc_vsr_t *xt, ppc_vsr_t *xb) \
{ \
int all_flags = 0; \
ppc_vsr_t t = { }; \
int i, flags; \
\
helper_reset_fpstatus(env); \
\
for (i = 0; i < nels; i++) { \
helper_reset_fpstatus(env); \
t.tfld = stp##_to_##ttp##_round_to_zero(xb->sfld, &env->fp_status); \
flags = env->fp_status.float_exception_flags; \
all_flags |= flags; \
if (unlikely(flags & float_flag_invalid)) { \
t.tfld = float_invalid_cvt(env, flags, t.tfld, rnan, 0, GETPC());\
} \
} \
\
*xt = t; \
env->fp_status.float_exception_flags = all_flags; \
do_float_check_status(env, sfi, GETPC()); \
}
@ -2945,15 +2947,16 @@ VSX_CVT_FP_TO_INT128(XSCVQPSQZ, int128, 0x8000000000000000ULL);
#define VSX_CVT_FP_TO_INT2(op, nels, stp, ttp, sfi, rnan) \
void helper_##op(CPUPPCState *env, ppc_vsr_t *xt, ppc_vsr_t *xb) \
{ \
int all_flags = 0; \
ppc_vsr_t t = { }; \
int i, flags; \
\
helper_reset_fpstatus(env); \
\
for (i = 0; i < nels; i++) { \
helper_reset_fpstatus(env); \
t.VsrW(2 * i) = stp##_to_##ttp##_round_to_zero(xb->VsrD(i), \
&env->fp_status); \
flags = env->fp_status.float_exception_flags; \
all_flags |= flags; \
if (unlikely(flags & float_flag_invalid)) { \
t.VsrW(2 * i) = float_invalid_cvt(env, flags, t.VsrW(2 * i), \
rnan, 0, GETPC()); \
@ -2962,6 +2965,7 @@ void helper_##op(CPUPPCState *env, ppc_vsr_t *xt, ppc_vsr_t *xb) \
} \
\
*xt = t; \
env->fp_status.float_exception_flags = all_flags; \
do_float_check_status(env, sfi, GETPC()); \
}