| Message ID | 20211020125724.78028-1-lucas.araujo@eldorado.org.br (mailing list archive) |
|---|---|
| Headers | show |
| Series | Fix mtfsf, mtfsfi and mtfsb1 bug | expand |
CC'ing the reporter On 20/10/2021 09:57, Lucas Mateus Castro (alqotel) wrote: > From: "Lucas Mateus Castro (alqotel)" <lucas.castro@eldorado.org.br> > > The instructions mtfsf, mtfsfi and mtfsb, when called, fail to set the FI > bit (bit 46 in the FPSCR) and can set to 1 the reserved bit 52 of the > FPSCR, as reported in https://gitlab.com/qemu-project/qemu/-/issues/266 > (although the bug report is only for mtfsf, the bug applies to mtfsfi and > mtfsb1 as well). > > These instructions also fail to throw an exception when the exception > and enabling bits are set, this can be tested by adding > 'prctl(PR_SET_FPEXC, PR_FP_EXC_PRECISE);' before the __builtin_mtfsf > call in the test case of the bug report. > > These patches aim to fix these issues. > > Lucas Mateus Castro (alqotel) (2): > target/ppc: Fixed call to deferred exception > target/ppc: ppc_store_fpscr doesn't update bit 52 > > target/ppc/cpu.c | 2 +- > target/ppc/cpu.h | 3 +++ > target/ppc/fpu_helper.c | 41 ++++++++++++++++++++++++++++++ > target/ppc/helper.h | 1 + > target/ppc/translate/fp-impl.c.inc | 6 ++--- > 5 files changed, 49 insertions(+), 4 deletions(-) > > -- > 2.31.1 > >
From: "Lucas Mateus Castro (alqotel)" <lucas.castro@eldorado.org.br> The instructions mtfsf, mtfsfi and mtfsb, when called, fail to set the FI bit (bit 46 in the FPSCR) and can set to 1 the reserved bit 52 of the FPSCR, as reported in https://gitlab.com/qemu-project/qemu/-/issues/266 (although the bug report is only for mtfsf, the bug applies to mtfsfi and mtfsb1 as well). These instructions also fail to throw an exception when the exception and enabling bits are set, this can be tested by adding 'prctl(PR_SET_FPEXC, PR_FP_EXC_PRECISE);' before the __builtin_mtfsf call in the test case of the bug report. These patches aim to fix these issues. Lucas Mateus Castro (alqotel) (2): target/ppc: Fixed call to deferred exception target/ppc: ppc_store_fpscr doesn't update bit 52 target/ppc/cpu.c | 2 +- target/ppc/cpu.h | 3 +++ target/ppc/fpu_helper.c | 41 ++++++++++++++++++++++++++++++ target/ppc/helper.h | 1 + target/ppc/translate/fp-impl.c.inc | 6 ++--- 5 files changed, 49 insertions(+), 4 deletions(-)