diff options
Diffstat (limited to 'gdb/findvar.c')
| -rw-r--r-- | gdb/findvar.c | 104 |
1 files changed, 42 insertions, 62 deletions
diff --git a/gdb/findvar.c b/gdb/findvar.c index 3ff8eccb656..163e9f7905a 100644 --- a/gdb/findvar.c +++ b/gdb/findvar.c @@ -258,25 +258,6 @@ store_address (addr, len, val) store_unsigned_integer (addr, len, val); } -/* Swap LEN bytes at BUFFER between target and host byte-order. */ -#define SWAP_FLOATING(buffer,len) \ - do \ - { \ - if (TARGET_BYTE_ORDER != HOST_BYTE_ORDER) \ - { \ - char tmp; \ - char *p = (char *)(buffer); \ - char *q = ((char *)(buffer)) + len - 1; \ - for (; p < q; p++, q--) \ - { \ - tmp = *q; \ - *q = *p; \ - *p = tmp; \ - } \ - } \ - } \ - while (0) - /* Extract a floating-point number from a target-order byte-stream at ADDR. Returns the value as type DOUBLEST. @@ -680,20 +661,22 @@ registers_fetched () register_valid[i] = 1; } -/* read_register_bytes and write_register_bytes are generally a *BAD* idea. - They are inefficient because they need to check for partial updates, which - can only be done by scanning through all of the registers and seeing if the - bytes that are being read/written fall inside of an invalid register. [The - main reason this is necessary is that register sizes can vary, so a simple - index won't suffice.] It is far better to call read_register_gen if you - want to get at the raw register contents, as it only takes a regno as an - argument, and therefore can't do a partial register update. It would also - be good to have a write_register_gen for similar reasons. - - Prior to the recent fixes to check for partial updates, both read and - write_register_bytes always checked to see if any registers were stale, and - then called target_fetch_registers (-1) to update the whole set. This - caused really slowed things down for remote targets. */ +/* read_register_bytes and write_register_bytes are generally a *BAD* + idea. They are inefficient because they need to check for partial + updates, which can only be done by scanning through all of the + registers and seeing if the bytes that are being read/written fall + inside of an invalid register. [The main reason this is necessary + is that register sizes can vary, so a simple index won't suffice.] + It is far better to call read_register_gen and write_register_gen + if you want to get at the raw register contents, as it only takes a + regno as an argument, and therefore can't do a partial register + update. + + Prior to the recent fixes to check for partial updates, both read + and write_register_bytes always checked to see if any registers + were stale, and then called target_fetch_registers (-1) to update + the whole set. This caused really slowed things down for remote + targets. */ /* Copy INLEN bytes of consecutive data from registers starting with the INREGBYTE'th byte of register data @@ -720,7 +703,6 @@ read_register_bytes (inregbyte, myaddr, inlen) for (regno = 0; regno < NUM_REGS; regno++) { int regstart, regend; - int startin, endin; if (register_valid[regno]) continue; @@ -731,15 +713,12 @@ read_register_bytes (inregbyte, myaddr, inlen) regstart = REGISTER_BYTE (regno); regend = regstart + REGISTER_RAW_SIZE (regno); - startin = regstart >= inregbyte && regstart < inregend; - endin = regend > inregbyte && regend <= inregend; - - if (!startin && !endin) + if (regend <= inregbyte || inregend <= regstart) + /* The range the user wants to read doesn't overlap with regno. */ continue; /* We've found an invalid register where at least one byte will be read. Update it from the target. */ - target_fetch_registers (regno); if (!register_valid[regno]) @@ -832,40 +811,41 @@ write_register_bytes (myregstart, myaddr, inlen) for (regno = 0; regno < NUM_REGS; regno++) { int regstart, regend; - int startin, endin; - char regbuf[MAX_REGISTER_RAW_SIZE]; regstart = REGISTER_BYTE (regno); regend = regstart + REGISTER_RAW_SIZE (regno); - startin = regstart >= myregstart && regstart < myregend; - endin = regend > myregstart && regend <= myregend; + /* Is this register completely outside the range the user is writing? */ + if (myregend <= regstart || regend <= myregstart) + /* do nothing */ ; - if (!startin && !endin) - continue; /* Register is completely out of range */ + /* Is this register completely within the range the user is writing? */ + else if (myregstart <= regstart && regend <= myregend) + write_register_gen (regno, myaddr + (regstart - myregstart)); - if (startin && endin) /* register is completely in range */ + /* The register partially overlaps the range being written. */ + else { - write_register_gen (regno, myaddr + (regstart - myregstart)); - continue; - } + char regbuf[MAX_REGISTER_RAW_SIZE]; + /* What's the overlap between this register's bytes and + those the caller wants to write? */ + int overlapstart = max (regstart, myregstart); + int overlapend = min (regend, myregend); - /* We may be doing a partial update of an invalid register. Update it - from the target before scribbling on it. */ - read_register_gen (regno, regbuf); - - if (startin) - memcpy (registers + regstart, - myaddr + regstart - myregstart, - myregend - regstart); - else /* endin */ - memcpy (registers + myregstart, - myaddr, - regend - myregstart); - target_store_registers (regno); + /* We may be doing a partial update of an invalid register. + Update it from the target before scribbling on it. */ + read_register_gen (regno, regbuf); + + memcpy (registers + overlapstart, + myaddr + (overlapstart - myregstart), + overlapend - overlapstart); + + target_store_registers (regno); + } } } + /* Return the raw contents of register REGNO, regarding it as an integer. */ /* This probably should be returning LONGEST rather than CORE_ADDR. */ |