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| author | Richard Kenner <kenner@gcc.gnu.org> | 1994-06-29 16:02:13 -0400 |
|---|---|---|
| committer | Richard Kenner <kenner@gcc.gnu.org> | 1994-06-29 16:02:13 -0400 |
| commit | 9ff3516a35fc7223000fd245f62da36045eeb6a9 (patch) | |
| tree | 9db9bc5cf502ce91868ef454586236e7dd18f705 | |
| parent | daf55ac69a0ab8a559d68d9b0b0b1fc2b120de26 (diff) | |
| download | gcc-9ff3516a35fc7223000fd245f62da36045eeb6a9.zip gcc-9ff3516a35fc7223000fd245f62da36045eeb6a9.tar.gz gcc-9ff3516a35fc7223000fd245f62da36045eeb6a9.tar.bz2 | |
(reload): Can't eliminate if frame pointer needed and TO is stack pointer.
Spill HARD_FRAME_POINTER_REGNUM if not FRAME_POINTER_REGNUM and frame pointer
is needed.
(spill_hard_reg): If CANT_ELIMINATE, set regs_ever_live; no longer done by
callers.
From-SVN: r7605
| -rw-r--r-- | gcc/reload1.c | 28 |
1 files changed, 21 insertions, 7 deletions
diff --git a/gcc/reload1.c b/gcc/reload1.c index 6f9d93d..360dc89 100644 --- a/gcc/reload1.c +++ b/gcc/reload1.c @@ -614,8 +614,7 @@ reload (first, global, dumpfile) { ep->can_eliminate = ep->can_eliminate_previous = (CAN_ELIMINATE (ep->from, ep->to) - && (ep->from != HARD_FRAME_POINTER_REGNUM - || ! frame_pointer_needed)); + && ! (ep->to == STACK_POINTER_REGNUM && frame_pointer_needed)); } #else reg_eliminate[0].can_eliminate = reg_eliminate[0].can_eliminate_previous @@ -703,10 +702,12 @@ reload (first, global, dumpfile) /* Spill any hard regs that we know we can't eliminate. */ for (ep = reg_eliminate; ep < ®_eliminate[NUM_ELIMINABLE_REGS]; ep++) if (! ep->can_eliminate) - { - spill_hard_reg (ep->from, global, dumpfile, 1); - regs_ever_live[ep->from] = 1; - } + spill_hard_reg (ep->from, global, dumpfile, 1); + +#if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM + if (frame_pointer_needed) + spill_hard_reg (HARD_FRAME_POINTER_REGNUM, global, dumpfile, 1); +#endif if (global) for (i = 0; i < N_REG_CLASSES; i++) @@ -760,6 +761,7 @@ reload (first, global, dumpfile) rtx max_nongroups_insn[N_REG_CLASSES]; rtx x; int starting_frame_size = get_frame_size (); + int previous_frame_pointer_needed = frame_pointer_needed; static char *reg_class_names[] = REG_CLASS_NAMES; something_changed = 0; @@ -1504,12 +1506,21 @@ reload (first, global, dumpfile) { ep->can_eliminate_previous = 0; spill_hard_reg (ep->from, global, dumpfile, 1); - regs_ever_live[ep->from] = 1; something_changed = 1; num_eliminable--; } } +#if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM + /* If we didn't need a frame pointer last time, but we do now, spill + the hard frame pointer. */ + if (frame_pointer_needed && ! previous_frame_pointer_needed) + { + spill_hard_reg (HARD_FRAME_POINTER_REGNUM, global, dumpfile, 1); + something_changed = 1; + } +#endif + /* If all needs are met, we win. */ for (i = 0; i < N_REG_CLASSES; i++) @@ -3355,6 +3366,9 @@ spill_hard_reg (regno, global, dumpfile, cant_eliminate) SET_HARD_REG_BIT (forbidden_regs, regno); + if (cant_eliminate) + regs_ever_live[regno] = 1; + /* Spill every pseudo reg that was allocated to this reg or to something that overlaps this reg. */ |