| Message ID | 20200914230210.2185860-11-richard.henderson@linaro.org |
|---|---|
| State | Superseded |
| Headers | show |
| Series | capstone + disassembler patches | expand |
On 15/09/2020 01.02, Richard Henderson wrote: > It is always possible to tell the length of an insn, even if the > actual insn is unknown. Skip the correct number of bytes, so that > we stay in sync with the instruction stream. > > Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> > Signed-off-by: Richard Henderson <richard.henderson@linaro.org> > --- > disas/capstone.c | 42 +++++++++++++++++++++++++++++++++++++++++- > 1 file changed, 41 insertions(+), 1 deletion(-) > > diff --git a/disas/capstone.c b/disas/capstone.c > index b48f83958d..0a9ef9c892 100644 > --- a/disas/capstone.c > +++ b/disas/capstone.c > @@ -16,6 +16,39 @@ > */ > static __thread cs_insn *cap_insn; > > +/* > + * The capstone library always skips 2 bytes for S390X. > + * This is less than ideal, since we can tell from the first two bits > + * the size of the insn and thus stay in sync with the insn stream. > + */ > +static size_t CAPSTONE_API > +cap_skipdata_s390x_cb(const uint8_t *code, size_t code_size, > + size_t offset, void *user_data) > +{ > + size_t ilen; > + > + /* See get_ilen() in target/s390x/internal.h. */ > + switch (code[offset] >> 6) { > + case 0: > + ilen = 2; > + break; > + case 1: > + case 2: > + ilen = 4; > + break; > + default: > + ilen = 6; > + break; > + } > + > + return ilen; > +} > + > +static const cs_opt_skipdata cap_skipdata_s390x = { > + .mnemonic = ".byte", > + .callback = cap_skipdata_s390x_cb > +}; > + > /* > * Initialize the Capstone library. > * > @@ -42,13 +75,20 @@ static cs_err cap_disas_start(disassemble_info *info, csh *handle) > /* "Disassemble" unknown insns as ".byte W,X,Y,Z". */ > cs_option(*handle, CS_OPT_SKIPDATA, CS_OPT_ON); > > - if (info->cap_arch == CS_ARCH_X86) { > + switch (info->cap_arch) { > + case CS_ARCH_SYSZ: > + cs_option(*handle, CS_OPT_SKIPDATA_SETUP, > + (uintptr_t)&cap_skipdata_s390x); > + break; > + > + case CS_ARCH_X86: > /* > * We don't care about errors (if for some reason the library > * is compiled without AT&T syntax); the user will just have > * to deal with the Intel syntax. > */ > cs_option(*handle, CS_OPT_SYNTAX, CS_OPT_SYNTAX_ATT); > + break; > } > > /* Allocate temp space for cs_disasm_iter. */ > Acked-by: Thomas Huth <thuth@redhat.com>
diff --git a/disas/capstone.c b/disas/capstone.c index b48f83958d..0a9ef9c892 100644 --- a/disas/capstone.c +++ b/disas/capstone.c @@ -16,6 +16,39 @@ */ static __thread cs_insn *cap_insn; +/* + * The capstone library always skips 2 bytes for S390X. + * This is less than ideal, since we can tell from the first two bits + * the size of the insn and thus stay in sync with the insn stream. + */ +static size_t CAPSTONE_API +cap_skipdata_s390x_cb(const uint8_t *code, size_t code_size, + size_t offset, void *user_data) +{ + size_t ilen; + + /* See get_ilen() in target/s390x/internal.h. */ + switch (code[offset] >> 6) { + case 0: + ilen = 2; + break; + case 1: + case 2: + ilen = 4; + break; + default: + ilen = 6; + break; + } + + return ilen; +} + +static const cs_opt_skipdata cap_skipdata_s390x = { + .mnemonic = ".byte", + .callback = cap_skipdata_s390x_cb +}; + /* * Initialize the Capstone library. * @@ -42,13 +75,20 @@ static cs_err cap_disas_start(disassemble_info *info, csh *handle) /* "Disassemble" unknown insns as ".byte W,X,Y,Z". */ cs_option(*handle, CS_OPT_SKIPDATA, CS_OPT_ON); - if (info->cap_arch == CS_ARCH_X86) { + switch (info->cap_arch) { + case CS_ARCH_SYSZ: + cs_option(*handle, CS_OPT_SKIPDATA_SETUP, + (uintptr_t)&cap_skipdata_s390x); + break; + + case CS_ARCH_X86: /* * We don't care about errors (if for some reason the library * is compiled without AT&T syntax); the user will just have * to deal with the Intel syntax. */ cs_option(*handle, CS_OPT_SYNTAX, CS_OPT_SYNTAX_ATT); + break; } /* Allocate temp space for cs_disasm_iter. */