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| author | Lucas Mateus Castro (alqotel) <lucas.araujo@eldorado.org.br> | 2021-12-17 17:57:12 +0100 |
|---|---|---|
| committer | Cédric Le Goater <clg@kaod.org> | 2021-12-17 17:57:12 +0100 |
| commit | c3a824b0cf23f98353fa91c715fe4918432d7928 (patch) | |
| tree | 27950607a47f2f2391b188f9d37ad41f44990bb3 /target/ppc/helper.h | |
| parent | 83234b8289e64fc359a5bf02d886a333d65b8f8c (diff) | |
target/ppc: Fixed call to deferred exception
mtfsf, mtfsfi and mtfsb1 instructions call helper_float_check_status
after updating the value of FPSCR, but helper_float_check_status
checks fp_status and fp_status isn't updated based on FPSCR and
since the value of fp_status is reset earlier in the instruction,
it's always 0.
Because of this helper_float_check_status would change the FI bit to 0
as this bit checks if the last operation was inexact and
float_flag_inexact is always 0.
These instructions also don't throw exceptions correctly since
helper_float_check_status throw exceptions based on fp_status.
This commit created a new helper, helper_fpscr_check_status that checks
FPSCR value instead of fp_status and checks for a larger variety of
exceptions than do_float_check_status.
Since fp_status isn't used, gen_reset_fpstatus() was removed.
The hardware used to compare QEMU's behavior to was a Power9.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Lucas Mateus Castro (alqotel) <lucas.araujo@eldorado.org.br>
Message-Id: <20211201163808.440385-2-lucas.araujo@eldorado.org.br>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Diffstat (limited to 'target/ppc/helper.h')
| -rw-r--r-- | target/ppc/helper.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/target/ppc/helper.h b/target/ppc/helper.h index 627811cefc..632a81c676 100644 --- a/target/ppc/helper.h +++ b/target/ppc/helper.h @@ -63,6 +63,7 @@ DEF_HELPER_FLAGS_1(cntlzw32, TCG_CALL_NO_RWG_SE, i32, i32) DEF_HELPER_FLAGS_2(brinc, TCG_CALL_NO_RWG_SE, tl, tl, tl) DEF_HELPER_1(float_check_status, void, env) +DEF_HELPER_1(fpscr_check_status, void, env) DEF_HELPER_1(reset_fpstatus, void, env) DEF_HELPER_2(compute_fprf_float64, void, env, i64) DEF_HELPER_3(store_fpscr, void, env, i64, i32) |