diff options
Diffstat (limited to 'gcc/lra-constraints.cc')
| -rw-r--r-- | gcc/lra-constraints.cc | 36 |
1 files changed, 28 insertions, 8 deletions
diff --git a/gcc/lra-constraints.cc b/gcc/lra-constraints.cc index 0659aed..7dbc7fe 100644 --- a/gcc/lra-constraints.cc +++ b/gcc/lra-constraints.cc @@ -152,6 +152,9 @@ static machine_mode curr_operand_mode[MAX_RECOG_OPERANDS]; (e.g. constant) and whose subreg is given operand of the current insn. VOIDmode in all other cases. */ static machine_mode original_subreg_reg_mode[MAX_RECOG_OPERANDS]; +/* The first call insn after curr_insn within the EBB during inherit_in_ebb + or NULL outside of that function. */ +static rtx_insn *first_call_insn; @@ -6373,12 +6376,26 @@ split_reg (bool before_p, int original_regno, rtx_insn *insn, lra_process_new_insns (as_a <rtx_insn *> (usage_insn), after_p ? NULL : restore, after_p ? restore : NULL, - call_save_p - ? "Add reg<-save" : "Add reg<-split"); - lra_process_new_insns (insn, before_p ? save : NULL, - before_p ? NULL : save, - call_save_p - ? "Add save<-reg" : "Add split<-reg"); + call_save_p ? "Add reg<-save" : "Add reg<-split"); + if (call_save_p + && first_call_insn != NULL + && BLOCK_FOR_INSN (first_call_insn) != BLOCK_FOR_INSN (insn)) + /* PR116028: If original_regno is a pseudo that has been assigned a + callee-saved hard register, then emit the spill insn before the call + insn 'first_call_insn' instead of adjacent to 'insn'. If 'insn' + and 'first_call_insn' belong to the same EBB but to two separate + BBs, and if 'insn' is present in the entry BB, then generating the + spill insn in the entry BB can prevent shrink wrap from happening. + This is because the spill insn references the stack pointer and + hence the prolog gets generated in the entry BB itself. It is + also more efficient to generate the spill before + 'first_call_insn' as the spill now occurs only in the path + containing the call. */ + lra_process_new_insns (first_call_insn, save, NULL, "Add save<-reg"); + else + lra_process_new_insns (insn, before_p ? save : NULL, + before_p ? NULL : save, + call_save_p ? "Add save<-reg" : "Add split<-reg"); if (nregs > 1 || original_regno < FIRST_PSEUDO_REGISTER) /* If we are trying to split multi-register. We should check conflicts on the next assignment sub-pass. IRA can allocate on @@ -6484,7 +6501,7 @@ split_if_necessary (int regno, machine_mode mode, && (INSN_UID (XEXP (next_usage_insns, 0)) < max_uid))) && need_for_split_p (potential_reload_hard_regs, regno + i) && split_reg (before_p, regno + i, insn, next_usage_insns, NULL)) - res = true; + res = true; return res; } @@ -7074,6 +7091,7 @@ inherit_in_ebb (rtx_insn *head, rtx_insn *tail) last_call_for_abi[callee_abi.id ()] = calls_num; full_and_partial_call_clobbers |= callee_abi.full_and_partial_reg_clobbers (); + first_call_insn = curr_insn; if ((cheap = find_reg_note (curr_insn, REG_RETURNED, NULL_RTX)) != NULL_RTX && ((cheap = XEXP (cheap, 0)), true) @@ -7142,6 +7160,7 @@ inherit_in_ebb (rtx_insn *head, rtx_insn *tail) { bool before_p; rtx_insn *use_insn = curr_insn; + rtx_insn *prev_insn = PREV_INSN (curr_insn); before_p = (JUMP_P (curr_insn) || (CALL_P (curr_insn) && reg->type == OP_IN)); @@ -7156,7 +7175,7 @@ inherit_in_ebb (rtx_insn *head, rtx_insn *tail) change_p = true; /* Invalidate. */ usage_insns[src_regno].check = 0; - if (before_p) + if (before_p && PREV_INSN (curr_insn) != prev_insn) use_insn = PREV_INSN (curr_insn); } if (NONDEBUG_INSN_P (curr_insn)) @@ -7278,6 +7297,7 @@ inherit_in_ebb (rtx_insn *head, rtx_insn *tail) } } } + first_call_insn = NULL; return change_p; } |