From 0b3092721e5cfa1697f1dafe81efefdbb0236f21 Mon Sep 17 00:00:00 2001 From: Andreas Arnez Date: Tue, 22 Jul 2014 10:28:32 +0000 Subject: [PATCH] regcache: Add functions suitable for regset_supply/collect. These functions are intended to suit all targets that don't require too special logic in their regset supply/collect methods. Having such generic functions helps reducing target-specific complexity. --- gdb/ChangeLog | 9 ++++++ gdb/regcache.c | 87 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ gdb/regcache.h | 45 ++++++++++++++++++++++++++++++ 3 files changed, 141 insertions(+) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index d775f94..346f3c8 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,5 +1,14 @@ 2014-08-07 Andreas Arnez + * regcache.c: Include "regset.h". + (regcache_transfer_regset): New local function. + (regcache_supply_regset, regcache_collect_regset): New functions. + * regcache.h (struct regcache_map_entry): New structure. + (REGCACHE_MAP_SKIP): New enum value. + (regcache_supply_regset, regcache_collect_regset): New prototypes. + +2014-08-07 Andreas Arnez + * regset.h (struct regset): Rename 'descr' field to 'regmap'. * ppc-linux-tdep.c (ppc_linux_supply_gregset) (ppc_linux_collect_gregset ): Likewise. diff --git a/gdb/regcache.c b/gdb/regcache.c index f410dc2..05b8fb9 100644 --- a/gdb/regcache.c +++ b/gdb/regcache.c @@ -28,6 +28,7 @@ #include "exceptions.h" #include "remote.h" #include "valprint.h" +#include "regset.h" /* * DATA STRUCTURE @@ -1066,6 +1067,92 @@ regcache_raw_collect (const struct regcache *regcache, int regnum, void *buf) memcpy (buf, regbuf, size); } +/* Transfer a single or all registers belonging to a certain register + set to or from a buffer. This is the main worker function for + regcache_supply_regset and regcache_collect_regset. */ + +static void +regcache_transfer_regset (const struct regset *regset, + const struct regcache *regcache, + struct regcache *out_regcache, + int regnum, const void *in_buf, + void *out_buf, size_t size) +{ + const struct regcache_map_entry *map; + int offs = 0, count; + + for (map = regset->regmap; (count = map->count) != 0; map++) + { + int regno = map->regno; + int slot_size = map->size; + + if (slot_size == 0 && regno != REGCACHE_MAP_SKIP) + slot_size = regcache->descr->sizeof_register[regno]; + + if (regno == REGCACHE_MAP_SKIP + || (regnum != -1 + && (regnum < regno || regnum >= regno + count))) + offs += count * slot_size; + + else if (regnum == -1) + for (; count--; regno++, offs += slot_size) + { + if (offs + slot_size > size) + break; + + if (out_buf) + regcache_raw_collect (regcache, regno, + (gdb_byte *) out_buf + offs); + else + regcache_raw_supply (out_regcache, regno, in_buf + ? (const gdb_byte *) in_buf + offs + : NULL); + } + else + { + /* Transfer a single register and return. */ + offs += (regnum - regno) * slot_size; + if (offs + slot_size > size) + return; + + if (out_buf) + regcache_raw_collect (regcache, regnum, + (gdb_byte *) out_buf + offs); + else + regcache_raw_supply (out_regcache, regnum, in_buf + ? (const gdb_byte *) in_buf + offs + : NULL); + return; + } + } +} + +/* Supply register REGNUM from BUF to REGCACHE, using the register map + in REGSET. If REGNUM is -1, do this for all registers in REGSET. + If BUF is NULL, set the register(s) to "unavailable" status. */ + +void +regcache_supply_regset (const struct regset *regset, + struct regcache *regcache, + int regnum, const void *buf, size_t size) +{ + regcache_transfer_regset (regset, regcache, regcache, regnum, + buf, NULL, size); +} + +/* Collect register REGNUM from REGCACHE to BUF, using the register + map in REGSET. If REGNUM is -1, do this for all registers in + REGSET. */ + +void +regcache_collect_regset (const struct regset *regset, + const struct regcache *regcache, + int regnum, void *buf, size_t size) +{ + regcache_transfer_regset (regset, regcache, NULL, regnum, + NULL, buf, size); +} + /* Special handling for register PC. */ diff --git a/gdb/regcache.h b/gdb/regcache.h index 8423f57..0361f22 100644 --- a/gdb/regcache.h +++ b/gdb/regcache.h @@ -147,6 +147,51 @@ extern void regcache_raw_supply (struct regcache *regcache, extern void regcache_raw_collect (const struct regcache *regcache, int regnum, void *buf); +/* Mapping between register numbers and offsets in a buffer, for use + in the '*regset' functions below. In an array of + 'regcache_map_entry' each element is interpreted like follows: + + - If 'regno' is a register number: Map register 'regno' to the + current offset (starting with 0) and increase the current offset + by 'size' (or the register's size, if 'size' is zero). Repeat + this with consecutive register numbers up to 'regno+count-1'. + + - If 'regno' is REGCACHE_MAP_SKIP: Add 'count*size' to the current + offset. + + - If count=0: End of the map. */ + +struct regcache_map_entry +{ + int count; + int regno; + int size; +}; + +/* Special value for the 'regno' field in the struct above. */ + +enum + { + REGCACHE_MAP_SKIP = -1, + }; + +/* Transfer a set of registers (as described by REGSET) between + REGCACHE and BUF. If REGNUM == -1, transfer all registers + belonging to the regset, otherwise just the register numbered + REGNUM. The REGSET's 'regmap' field must point to an array of + 'struct regcache_map_entry'. + + These functions are suitable for the 'regset_supply' and + 'regset_collect' fields in a regset structure. */ + +extern void regcache_supply_regset (const struct regset *regset, + struct regcache *regcache, + int regnum, const void *buf, + size_t size); +extern void regcache_collect_regset (const struct regset *regset, + const struct regcache *regcache, + int regnum, void *buf, size_t size); + /* The type of a register. This function is slightly more efficient then its gdbarch vector counterpart since it returns a precomputed -- 2.7.4