diff options
Diffstat (limited to 'gcc/rtlanal.c')
| -rw-r--r-- | gcc/rtlanal.c | 40 |
1 files changed, 40 insertions, 0 deletions
diff --git a/gcc/rtlanal.c b/gcc/rtlanal.c index 891799b..e9a9816 100644 --- a/gcc/rtlanal.c +++ b/gcc/rtlanal.c @@ -26,6 +26,7 @@ Boston, MA 02111-1307, USA. */ static int rtx_addr_can_trap_p PARAMS ((rtx)); static void reg_set_p_1 PARAMS ((rtx, rtx, void *)); +static void insn_dependant_p_1 PARAMS ((rtx, rtx, void *)); static void reg_set_last_1 PARAMS ((rtx, rtx, void *)); @@ -687,6 +688,45 @@ modified_in_p (x, insn) return 0; } + +/* Return true if anything in insn X is (anti,output,true) dependant on + anything in insn Y. */ + +int +insn_dependant_p (x, y) + rtx x, y; +{ + rtx tmp; + + if (! INSN_P (x) || ! INSN_P (y)) + abort (); + + tmp = PATTERN (y); + note_stores (PATTERN (x), insn_dependant_p_1, &tmp); + if (tmp == NULL_RTX) + return 1; + + tmp = PATTERN (x); + note_stores (PATTERN (y), insn_dependant_p_1, &tmp); + if (tmp == NULL_RTX) + return 1; + + return 0; +} + +/* A helper routine for insn_dependant_p called through note_stores. */ + +static void +insn_dependant_p_1 (x, pat, data) + rtx x; + rtx pat ATTRIBUTE_UNUSED; + void *data; +{ + rtx * pinsn = (rtx *) data; + + if (*pinsn && reg_mentioned_p (x, *pinsn)) + *pinsn = NULL_RTX; +} /* Given an INSN, return a SET expression if this insn has only a single SET. It may also have CLOBBERs, USEs, or SET whose output |