| Message ID | 20180611171007.4165-2-peter.maydell@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | Add ldn_*_p() and stn_*_p() and use them in exec.c | expand |
Hi Peter, On 06/11/2018 02:10 PM, Peter Maydell wrote: > There's a common pattern in QEMU where a function needs to perform > a data load or store of an N byte integer in a particular endianness. > At the moment this is handled by doing a switch() on the size and > calling the appropriate ld*_p or st*_p function for each size. > > Provide a new family of functions ldn_*_p() and stn_*_p() which > take the size as an argument and do the switch() themselves. > > Signed-off-by: Peter Maydell <peter.maydell@linaro.org> > --- > include/exec/cpu-all.h | 4 +++ > include/qemu/bswap.h | 52 +++++++++++++++++++++++++++++++++++++ > docs/devel/loads-stores.rst | 15 +++++++++++ > 3 files changed, 71 insertions(+) > > diff --git a/include/exec/cpu-all.h b/include/exec/cpu-all.h > index a635f532f97..07ec3808342 100644 > --- a/include/exec/cpu-all.h > +++ b/include/exec/cpu-all.h > @@ -133,6 +133,8 @@ static inline void tswap64s(uint64_t *s) > #define stq_p(p, v) stq_be_p(p, v) > #define stfl_p(p, v) stfl_be_p(p, v) > #define stfq_p(p, v) stfq_be_p(p, v) > +#define ldn_p(p, sz ldn_be_p(p, sz) > +#define stn_p(p, sz, v) stn_be_p(p, sz, v) > #else > #define lduw_p(p) lduw_le_p(p) > #define ldsw_p(p) ldsw_le_p(p) > @@ -145,6 +147,8 @@ static inline void tswap64s(uint64_t *s) > #define stq_p(p, v) stq_le_p(p, v) > #define stfl_p(p, v) stfl_le_p(p, v) > #define stfq_p(p, v) stfq_le_p(p, v) > +#define ldn_p(p, sz) ldn_le_p(p, sz) > +#define stn_p(p, sz, v) stn_le_p(p, sz, v) > #endif > > /* MMU memory access macros */ > diff --git a/include/qemu/bswap.h b/include/qemu/bswap.h > index 3f28f661b15..a684c1a7a29 100644 > --- a/include/qemu/bswap.h > +++ b/include/qemu/bswap.h > @@ -290,6 +290,15 @@ typedef union { > * For accessors that take a guest address rather than a > * host address, see the cpu_{ld,st}_* accessors defined in > * cpu_ldst.h. > + * > + * For cases where the size to be used is not fixed at compile time, > + * there are > + * stn{endian}_p(ptr, sz, val) > + * which stores @val to @ptr as an @endian-order number @sz bytes in size > + * and > + * ldn{endian}_p(ptr, sz) > + * which loads @sz bytes from @ptr as an unsigned @endian-order number > + * and returns it in a uint64_t. > */ > > static inline int ldub_p(const void *ptr) > @@ -495,6 +504,49 @@ static inline unsigned long leul_to_cpu(unsigned long v) > #endif > } > > +/* Store v to p as a sz byte value in host order */ > +#define DO_STN_LDN_P(END) \ > + static inline void stn_## END ## _p(void *ptr, int sz, uint64_t v) \ > + { \ > + switch (sz) { \ > + case 1: \ > + stb_p(ptr, v); \ > + break; \ > + case 2: \ > + stw_ ## END ## _p(ptr, v); \ > + break; \ > + case 4: \ > + stl_ ## END ## _p(ptr, v); \ > + break; \ > + case 8: \ > + stq_ ## END ## _p(ptr, v); \ > + break; \ > + default: \ > + g_assert_not_reached(); \ As with the recent discussion with Markus about whether using abort() or g_assert_not_reached(), I'd prefer to keep abort() here (which is what exec.c currently uses). [http://lists.nongnu.org/archive/html/qemu-devel/2018-06/msg01869.html] > + } \ > + } \ > + static inline uint64_t ldn_## END ## _p(const void *ptr, int sz) \ > + { \ > + switch (sz) { \ > + case 1: \ > + return ldub_p(ptr); \ > + case 2: \ > + return lduw_ ## END ## _p(ptr); \ > + case 4: \ > + return (uint32_t)ldl_ ## END ## _p(ptr); \ > + case 8: \ > + return ldq_ ## END ## _p(ptr); \ > + default: \ > + g_assert_not_reached(); \ Ditto. > + } \ > + } > + > +DO_STN_LDN_P(he) > +DO_STN_LDN_P(le) > +DO_STN_LDN_P(be) > + > +#undef DO_STN_LDN_P > + > #undef le_bswap > #undef be_bswap > #undef le_bswaps > diff --git a/docs/devel/loads-stores.rst b/docs/devel/loads-stores.rst > index 6a990cc2438..57d8c524bfe 100644 > --- a/docs/devel/loads-stores.rst > +++ b/docs/devel/loads-stores.rst > @@ -53,9 +53,24 @@ The ``_{endian}`` infix is omitted for target-endian accesses. > The target endian accessors are only available to source > files which are built per-target. > > +There are also functions which take the size as an argument: > + > +load: ``ldn{endian}_p(ptr, sz)`` > + > +which performs an unsigned load of ``sz`` bytes from ``ptr`` > +as an ``{endian}`` order value and returns it in a uint64_t. > + > +store: ``stn{endian}_p(ptr, sz, val)`` > + > +which stores ``val`` to ``ptr`` as an ``{endian}`` order value > +of size ``sz`` bytes. > + > + > Regexes for git grep > - ``\<ldf\?[us]\?[bwlq]\(_[hbl]e\)\?_p\>`` > - ``\<stf\?[bwlq]\(_[hbl]e\)\?_p\>`` > + - ``\<ldn_\([hbl]e\)?_p\>`` > + - ``\<stn_\([hbl]e\)?_p\>`` > > ``cpu_{ld,st}_*`` > ~~~~~~~~~~~~~~~~~ > Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
On 11 June 2018 at 18:43, Philippe Mathieu-Daudé <f4bug@amsat.org> wrote: > Hi Peter, > > On 06/11/2018 02:10 PM, Peter Maydell wrote: >> +/* Store v to p as a sz byte value in host order */ >> +#define DO_STN_LDN_P(END) \ >> + static inline void stn_## END ## _p(void *ptr, int sz, uint64_t v) \ >> + { \ >> + switch (sz) { \ >> + case 1: \ >> + stb_p(ptr, v); \ >> + break; \ >> + case 2: \ >> + stw_ ## END ## _p(ptr, v); \ >> + break; \ >> + case 4: \ >> + stl_ ## END ## _p(ptr, v); \ >> + break; \ >> + case 8: \ >> + stq_ ## END ## _p(ptr, v); \ >> + break; \ >> + default: \ >> + g_assert_not_reached(); \ > > As with the recent discussion with Markus about whether using abort() or > g_assert_not_reached(), I'd prefer to keep abort() here (which is what > exec.c currently uses). > > [http://lists.nongnu.org/archive/html/qemu-devel/2018-06/msg01869.html] I couldn't find anything obvious about the merits of abort() vs g_assert_not_reached() in that email. g_assert_not_reached() is clear about what it's doing and we use it in hundreds of places in the codebase, whereas abort() is used for various things, including situations where flow-of-execution clearly can get to that location. So I prefer g_assert_not_reached(). thanks -- PMM
On 11 June 2018 at 18:10, Peter Maydell <peter.maydell@linaro.org> wrote: > There's a common pattern in QEMU where a function needs to perform > a data load or store of an N byte integer in a particular endianness. > At the moment this is handled by doing a switch() on the size and > calling the appropriate ld*_p or st*_p function for each size. > > Provide a new family of functions ldn_*_p() and stn_*_p() which > take the size as an argument and do the switch() themselves. > > Signed-off-by: Peter Maydell <peter.maydell@linaro.org> > --- > include/exec/cpu-all.h | 4 +++ > include/qemu/bswap.h | 52 +++++++++++++++++++++++++++++++++++++ > docs/devel/loads-stores.rst | 15 +++++++++++ > 3 files changed, 71 insertions(+) > > diff --git a/include/exec/cpu-all.h b/include/exec/cpu-all.h > index a635f532f97..07ec3808342 100644 > --- a/include/exec/cpu-all.h > +++ b/include/exec/cpu-all.h > @@ -133,6 +133,8 @@ static inline void tswap64s(uint64_t *s) > #define stq_p(p, v) stq_be_p(p, v) > #define stfl_p(p, v) stfl_be_p(p, v) > #define stfq_p(p, v) stfq_be_p(p, v) > +#define ldn_p(p, sz ldn_be_p(p, sz) Silly typo here -- missing ')'. thanks -- PMM
On 06/11/2018 07:52 AM, Peter Maydell wrote: > On 11 June 2018 at 18:10, Peter Maydell <peter.maydell@linaro.org> wrote: >> There's a common pattern in QEMU where a function needs to perform >> a data load or store of an N byte integer in a particular endianness. >> At the moment this is handled by doing a switch() on the size and >> calling the appropriate ld*_p or st*_p function for each size. >> >> Provide a new family of functions ldn_*_p() and stn_*_p() which >> take the size as an argument and do the switch() themselves. >> >> Signed-off-by: Peter Maydell <peter.maydell@linaro.org> >> --- >> include/exec/cpu-all.h | 4 +++ >> include/qemu/bswap.h | 52 +++++++++++++++++++++++++++++++++++++ >> docs/devel/loads-stores.rst | 15 +++++++++++ >> 3 files changed, 71 insertions(+) >> >> diff --git a/include/exec/cpu-all.h b/include/exec/cpu-all.h >> index a635f532f97..07ec3808342 100644 >> --- a/include/exec/cpu-all.h >> +++ b/include/exec/cpu-all.h >> @@ -133,6 +133,8 @@ static inline void tswap64s(uint64_t *s) >> #define stq_p(p, v) stq_be_p(p, v) >> #define stfl_p(p, v) stfl_be_p(p, v) >> #define stfq_p(p, v) stfq_be_p(p, v) >> +#define ldn_p(p, sz ldn_be_p(p, sz) > > Silly typo here -- missing ')'. Reviewed-by: Richard Henderson <richard.henderson@linaro.org> r~
diff --git a/include/exec/cpu-all.h b/include/exec/cpu-all.h index a635f532f97..07ec3808342 100644 --- a/include/exec/cpu-all.h +++ b/include/exec/cpu-all.h @@ -133,6 +133,8 @@ static inline void tswap64s(uint64_t *s) #define stq_p(p, v) stq_be_p(p, v) #define stfl_p(p, v) stfl_be_p(p, v) #define stfq_p(p, v) stfq_be_p(p, v) +#define ldn_p(p, sz ldn_be_p(p, sz) +#define stn_p(p, sz, v) stn_be_p(p, sz, v) #else #define lduw_p(p) lduw_le_p(p) #define ldsw_p(p) ldsw_le_p(p) @@ -145,6 +147,8 @@ static inline void tswap64s(uint64_t *s) #define stq_p(p, v) stq_le_p(p, v) #define stfl_p(p, v) stfl_le_p(p, v) #define stfq_p(p, v) stfq_le_p(p, v) +#define ldn_p(p, sz) ldn_le_p(p, sz) +#define stn_p(p, sz, v) stn_le_p(p, sz, v) #endif /* MMU memory access macros */ diff --git a/include/qemu/bswap.h b/include/qemu/bswap.h index 3f28f661b15..a684c1a7a29 100644 --- a/include/qemu/bswap.h +++ b/include/qemu/bswap.h @@ -290,6 +290,15 @@ typedef union { * For accessors that take a guest address rather than a * host address, see the cpu_{ld,st}_* accessors defined in * cpu_ldst.h. + * + * For cases where the size to be used is not fixed at compile time, + * there are + * stn{endian}_p(ptr, sz, val) + * which stores @val to @ptr as an @endian-order number @sz bytes in size + * and + * ldn{endian}_p(ptr, sz) + * which loads @sz bytes from @ptr as an unsigned @endian-order number + * and returns it in a uint64_t. */ static inline int ldub_p(const void *ptr) @@ -495,6 +504,49 @@ static inline unsigned long leul_to_cpu(unsigned long v) #endif } +/* Store v to p as a sz byte value in host order */ +#define DO_STN_LDN_P(END) \ + static inline void stn_## END ## _p(void *ptr, int sz, uint64_t v) \ + { \ + switch (sz) { \ + case 1: \ + stb_p(ptr, v); \ + break; \ + case 2: \ + stw_ ## END ## _p(ptr, v); \ + break; \ + case 4: \ + stl_ ## END ## _p(ptr, v); \ + break; \ + case 8: \ + stq_ ## END ## _p(ptr, v); \ + break; \ + default: \ + g_assert_not_reached(); \ + } \ + } \ + static inline uint64_t ldn_## END ## _p(const void *ptr, int sz) \ + { \ + switch (sz) { \ + case 1: \ + return ldub_p(ptr); \ + case 2: \ + return lduw_ ## END ## _p(ptr); \ + case 4: \ + return (uint32_t)ldl_ ## END ## _p(ptr); \ + case 8: \ + return ldq_ ## END ## _p(ptr); \ + default: \ + g_assert_not_reached(); \ + } \ + } + +DO_STN_LDN_P(he) +DO_STN_LDN_P(le) +DO_STN_LDN_P(be) + +#undef DO_STN_LDN_P + #undef le_bswap #undef be_bswap #undef le_bswaps diff --git a/docs/devel/loads-stores.rst b/docs/devel/loads-stores.rst index 6a990cc2438..57d8c524bfe 100644 --- a/docs/devel/loads-stores.rst +++ b/docs/devel/loads-stores.rst @@ -53,9 +53,24 @@ The ``_{endian}`` infix is omitted for target-endian accesses. The target endian accessors are only available to source files which are built per-target. +There are also functions which take the size as an argument: + +load: ``ldn{endian}_p(ptr, sz)`` + +which performs an unsigned load of ``sz`` bytes from ``ptr`` +as an ``{endian}`` order value and returns it in a uint64_t. + +store: ``stn{endian}_p(ptr, sz, val)`` + +which stores ``val`` to ``ptr`` as an ``{endian}`` order value +of size ``sz`` bytes. + + Regexes for git grep - ``\<ldf\?[us]\?[bwlq]\(_[hbl]e\)\?_p\>`` - ``\<stf\?[bwlq]\(_[hbl]e\)\?_p\>`` + - ``\<ldn_\([hbl]e\)?_p\>`` + - ``\<stn_\([hbl]e\)?_p\>`` ``cpu_{ld,st}_*`` ~~~~~~~~~~~~~~~~~
There's a common pattern in QEMU where a function needs to perform a data load or store of an N byte integer in a particular endianness. At the moment this is handled by doing a switch() on the size and calling the appropriate ld*_p or st*_p function for each size. Provide a new family of functions ldn_*_p() and stn_*_p() which take the size as an argument and do the switch() themselves. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> --- include/exec/cpu-all.h | 4 +++ include/qemu/bswap.h | 52 +++++++++++++++++++++++++++++++++++++ docs/devel/loads-stores.rst | 15 +++++++++++ 3 files changed, 71 insertions(+)