diff options
Diffstat (limited to 'gcc/reload1.c')
| -rw-r--r-- | gcc/reload1.c | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/gcc/reload1.c b/gcc/reload1.c index 3d849b6..f6d9a0f 100644 --- a/gcc/reload1.c +++ b/gcc/reload1.c @@ -5799,6 +5799,47 @@ choose_reload_regs (insn, avoid_return_reg) reload_opnum[r], reload_when_needed[r])) reload_inherited[r] = 0; + /* If we can inherit a RELOAD_FOR_INPUT, then we do not need its related + RELOAD_FOR_INPUT_ADDRESS / RELOAD_FOR_INPADDR_ADDRESS reloads. + ??? This could be extended to other reload types, but these are + more tricky to handle: + RELOAD_FOR_OTHER_ADDRESS reloads might have been merged, so we + can't eliminate them without a check that *all* references are + now unused due to inheritance. + While RELOAD_FOR_INPADDR_ADDRESS and RELOAD_FOR_OUTADDR_ADDRESS are + not merged, we can't be sure that we have eliminated the use of + that particular reload if we have seen just one + RELOAD_FOR_INPUT_ADDRESS / RELOAD_FOR_OUTPUT_ADDRESS being inherited, + since there might be multiple of the latter two reloads for a single + operand. + RELOAD_FOR_OPADDR_ADDR reloads for different operands are not + merged, but might share the same register by courtesy of + reload_reg_free_for_value_p. reload_reg_used_in_op_addr_reload + does not differentiate by opnum, thus calling clear_reload_reg_in_use + for one of these reloads would mark the register as free even though + another RELOAD_FOR_OPADDR_ADDR reload might still use it. */ + else if (reload_inherited[r] && reload_when_needed[r] == RELOAD_FOR_INPUT) + { + for (i = 0; i < n_reloads; i++) + { + if ((reload_when_needed[i] == RELOAD_FOR_INPUT_ADDRESS + || reload_when_needed[i] == RELOAD_FOR_INPADDR_ADDRESS) + && reload_opnum[i] == reload_opnum[r] + && reload_in[i] && reload_reg_rtx[i]) + { + int regno = true_regnum (reload_reg_rtx[i]); + + reload_in[i] = 0; + if (spill_reg_order[regno] >= 0) + clear_reload_reg_in_use (regno, reload_opnum[i], + reload_when_needed[i], + reload_mode[i]); + reload_reg_rtx[i] = 0; + reload_spill_index[i] = -1; + remove_replacements (i); + } + } + } /* If we found a better place to reload from, validate it in the same fashion, if it is a reload reg. */ |