diff options
Diffstat (limited to 'gcc/resource.c')
| -rw-r--r-- | gcc/resource.c | 21 |
1 files changed, 16 insertions, 5 deletions
diff --git a/gcc/resource.c b/gcc/resource.c index daa839c54a7..880264594f7 100644 --- a/gcc/resource.c +++ b/gcc/resource.c @@ -1239,17 +1239,20 @@ mark_end_of_function_resources (trial, include_delayed_effects) include_delayed_effects); } -/* Try to find an available hard register of mode MODE at - CURRENT_INSN, matching the register class in CLASS_STR. Registers - that already have bits set in REG_SET will not be considered. +/* Try to find a hard register of mode MODE, matching the register class in + CLASS_STR, which is available at the beginning of insn CURRENT_INSN and + remains available until the end of LAST_INSN. LAST_INSN may be NULL_RTX, + in which case the only condition is that the register must be available + before CURRENT_INSN. + Registers that already have bits set in REG_SET will not be considered. If an appropriate register is available, it will be returned and the corresponding bit(s) in REG_SET will be set; otherwise, NULL_RTX is returned. */ rtx -find_free_register (current_insn, class_str, mode, reg_set) - rtx current_insn; +find_free_register (current_insn, last_insn, class_str, mode, reg_set) + rtx current_insn, last_insn; char *class_str; int mode; HARD_REG_SET *reg_set; @@ -1261,6 +1264,14 @@ find_free_register (current_insn, class_str, mode, reg_set) = (clet == 'r' ? GENERAL_REGS : REG_CLASS_FROM_LETTER (clet)); mark_target_live_regs (get_insns (), current_insn, &used); + if (last_insn) + while (current_insn != last_insn) + { + /* Exclude anything set in this insn. */ + mark_set_resources (PATTERN (current_insn), &used, 0, 1); + current_insn = next_nonnote_insn (current_insn); + } + for (i = 0; i < FIRST_PSEUDO_REGISTER; i++) { |