diff options
Diffstat (limited to 'gcc/local-alloc.c')
| -rw-r--r-- | gcc/local-alloc.c | 88 |
1 files changed, 68 insertions, 20 deletions
diff --git a/gcc/local-alloc.c b/gcc/local-alloc.c index dc56ca47917..4ef1f021f03 100644 --- a/gcc/local-alloc.c +++ b/gcc/local-alloc.c @@ -1211,13 +1211,9 @@ update_equiv_regs (void) if (!bitmap_empty_p (cleared_regs)) FOR_EACH_BB (bb) { - bitmap_and_compl_into (DF_RA_LIVE_IN (bb), cleared_regs); - if (DF_RA_LIVE_TOP (bb)) - bitmap_and_compl_into (DF_RA_LIVE_TOP (bb), cleared_regs); - bitmap_and_compl_into (DF_RA_LIVE_OUT (bb), cleared_regs); + bitmap_and_compl_into (DF_LIVE_IN (bb), cleared_regs); + bitmap_and_compl_into (DF_LIVE_OUT (bb), cleared_regs); bitmap_and_compl_into (DF_LR_IN (bb), cleared_regs); - if (DF_LR_TOP (bb)) - bitmap_and_compl_into (DF_LR_TOP (bb), cleared_regs); bitmap_and_compl_into (DF_LR_OUT (bb), cleared_regs); } @@ -1277,6 +1273,7 @@ block_alloc (int b) int max_uid = get_max_uid (); int *qty_order; int no_conflict_combined_regno = -1; + struct df_ref ** def_rec; /* Count the instructions in the basic block. */ @@ -1299,7 +1296,19 @@ block_alloc (int b) /* Initialize table of hardware registers currently live. */ - REG_SET_TO_HARD_REG_SET (regs_live, DF_LR_TOP (BASIC_BLOCK (b))); + REG_SET_TO_HARD_REG_SET (regs_live, DF_LR_IN (BASIC_BLOCK (b))); + + /* This is conservative, as this would include registers that are + artificial-def'ed-but-not-used. However, artificial-defs are + rare, and such uninitialized use is rarer still, and the chance + of this having any performance impact is even less, while the + benefit is not having to compute and keep the TOP set around. */ + for (def_rec = df_get_artificial_defs (b); *def_rec; def_rec++) + { + int regno = DF_REF_REGNO (*def_rec); + if (regno < FIRST_PSEUDO_REGISTER) + SET_HARD_REG_BIT (regs_live, regno); + } /* This loop scans the instructions of the basic block and assigns quantities to registers. @@ -2502,6 +2511,49 @@ dump_local_alloc (FILE *file) fprintf (file, ";; Register %d in %d.\n", i, reg_renumber[i]); } +#ifdef STACK_REGS +static void +find_stack_regs (void) +{ + bitmap stack_regs = BITMAP_ALLOC (NULL); + int i; + HARD_REG_SET stack_hard_regs, used; + basic_block bb; + + /* Any register that MAY be allocated to a register stack (like the + 387) is treated poorly. Each such register is marked as being + live everywhere. This keeps the register allocator and the + subsequent passes from doing anything useful with these values. + + FIXME: This seems like an incredibly poor idea. */ + + CLEAR_HARD_REG_SET (stack_hard_regs); + for (i = FIRST_STACK_REG; i <= LAST_STACK_REG; i++) + SET_HARD_REG_BIT (stack_hard_regs, i); + + for (i = FIRST_PSEUDO_REGISTER; i < max_regno; i++) + { + COPY_HARD_REG_SET (used, reg_class_contents[reg_preferred_class (i)]); + IOR_HARD_REG_SET (used, reg_class_contents[reg_alternate_class (i)]); + AND_HARD_REG_SET (used, stack_hard_regs); + if (!hard_reg_set_empty_p (used)) + bitmap_set_bit (stack_regs, i); + } + + if (dump_file) + bitmap_print (dump_file, stack_regs, "stack regs:", "\n"); + + FOR_EACH_BB (bb) + { + bitmap_ior_into (DF_LIVE_IN (bb), stack_regs); + bitmap_and_into (DF_LIVE_IN (bb), DF_LR_IN (bb)); + bitmap_ior_into (DF_LIVE_OUT (bb), stack_regs); + bitmap_and_into (DF_LIVE_OUT (bb), DF_LR_OUT (bb)); + } + BITMAP_FREE (stack_regs); +} +#endif + /* Run old register allocator. Return TRUE if we must exit rest_of_compilation upon return. */ static unsigned int @@ -2512,26 +2564,22 @@ rest_of_handle_local_alloc (void) df_note_add_problem (); - if (optimize > 1) - df_remove_problem (df_live); - /* Create a new version of df that has the special version of UR if - we are doing optimization. */ - if (optimize) - df_urec_add_problem (); + if (optimize == 1) + { + df_live_add_problem (); + df_live_set_all_dirty (); + } #ifdef ENABLE_CHECKING df->changeable_flags |= DF_VERIFY_SCHEDULED; #endif df_analyze (); +#ifdef STACK_REGS + if (optimize) + find_stack_regs (); +#endif regstat_init_n_sets_and_refs (); regstat_compute_ri (); - /* There is just too much going on in the register allocators to - keep things up to date. At the end we have to rescan anyway - because things change when the reload_completed flag is set. - So we just turn off scanning and we will rescan by hand. */ - df_set_flags (DF_NO_INSN_RESCAN); - - /* If we are not optimizing, then this is the only place before register allocation where dataflow is done. And that is needed to generate these warnings. */ |