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author | Lucas Mateus Castro (alqotel) | 2021-12-17 17:57:12 +0100 |
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committer | Cédric Le Goater | 2021-12-17 17:57:12 +0100 |
commit | c3a824b0cf23f98353fa91c715fe4918432d7928 (patch) | |
tree | 27950607a47f2f2391b188f9d37ad41f44990bb3 /target/ppc/fpu_helper.c | |
parent | hw/ppc/mac.h: Remove MAX_CPUS macro (diff) | |
download | qemu-c3a824b0cf23f98353fa91c715fe4918432d7928.tar.gz qemu-c3a824b0cf23f98353fa91c715fe4918432d7928.tar.xz qemu-c3a824b0cf23f98353fa91c715fe4918432d7928.zip |
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/fpu_helper.c')
-rw-r--r-- | target/ppc/fpu_helper.c | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/target/ppc/fpu_helper.c b/target/ppc/fpu_helper.c index c4896cecc8..bb72715827 100644 --- a/target/ppc/fpu_helper.c +++ b/target/ppc/fpu_helper.c @@ -414,6 +414,54 @@ void helper_store_fpscr(CPUPPCState *env, uint64_t val, uint32_t nibbles) ppc_store_fpscr(env, val); } +void helper_fpscr_check_status(CPUPPCState *env) +{ + CPUState *cs = env_cpu(env); + target_ulong fpscr = env->fpscr; + int error = 0; + + if ((fpscr & FP_OX) && (fpscr & FP_OE)) { + error = POWERPC_EXCP_FP_OX; + } else if ((fpscr & FP_UX) && (fpscr & FP_UE)) { + error = POWERPC_EXCP_FP_UX; + } else if ((fpscr & FP_XX) && (fpscr & FP_XE)) { + error = POWERPC_EXCP_FP_XX; + } else if ((fpscr & FP_ZX) && (fpscr & FP_ZE)) { + error = POWERPC_EXCP_FP_ZX; + } else if (fpscr & FP_VE) { + if (fpscr & FP_VXSOFT) { + error = POWERPC_EXCP_FP_VXSOFT; + } else if (fpscr & FP_VXSNAN) { + error = POWERPC_EXCP_FP_VXSNAN; + } else if (fpscr & FP_VXISI) { + error = POWERPC_EXCP_FP_VXISI; + } else if (fpscr & FP_VXIDI) { + error = POWERPC_EXCP_FP_VXIDI; + } else if (fpscr & FP_VXZDZ) { + error = POWERPC_EXCP_FP_VXZDZ; + } else if (fpscr & FP_VXIMZ) { + error = POWERPC_EXCP_FP_VXIMZ; + } else if (fpscr & FP_VXVC) { + error = POWERPC_EXCP_FP_VXVC; + } else if (fpscr & FP_VXSQRT) { + error = POWERPC_EXCP_FP_VXSQRT; + } else if (fpscr & FP_VXCVI) { + error = POWERPC_EXCP_FP_VXCVI; + } else { + return; + } + } else { + return; + } + cs->exception_index = POWERPC_EXCP_PROGRAM; + env->error_code = error | POWERPC_EXCP_FP; + /* Deferred floating-point exception after target FPSCR update */ + if (fp_exceptions_enabled(env)) { + raise_exception_err_ra(env, cs->exception_index, + env->error_code, GETPC()); + } +} + static void do_float_check_status(CPUPPCState *env, uintptr_t raddr) { CPUState *cs = env_cpu(env); |