From d445b551ca68b08aa1122e6ee57bcaa8e46ccb34 Mon Sep 17 00:00:00 2001 From: Richard Kenner Date: Wed, 1 Jan 1992 16:50:07 -0500 Subject: [PATCH] *** empty log message *** From-SVN: r152 --- gcc/reload1.c | 152 +++++++++++++++++++++++++++----------------------- 1 file changed, 83 insertions(+), 69 deletions(-) diff --git a/gcc/reload1.c b/gcc/reload1.c index cc196a8139a..8af7b0caa58 100644 --- a/gcc/reload1.c +++ b/gcc/reload1.c @@ -494,7 +494,6 @@ reload (first, global, dumpfile) int something_needs_elimination; int new_basic_block_needs; int caller_save_needs_spill; - int old_caller_save_needed = caller_save_needed; /* The basic block number currently being processed for INSN. */ int this_block; @@ -517,9 +516,9 @@ reload (first, global, dumpfile) bzero (spill_stack_slot, sizeof spill_stack_slot); bzero (spill_stack_slot_width, sizeof spill_stack_slot_width); - /* If caller-saves are needed, allocate the required save areas. */ - if (caller_save_needed) - allocate_save_areas (); + /* If caller-saves are requested, initialize the required save areas. */ + if (flag_caller_saves) + init_save_areas (); /* Compute which hard registers are now in use as homes for pseudo registers. @@ -581,7 +580,7 @@ reload (first, global, dumpfile) reg_equiv_constant[i] = x; else reg_equiv_memory_loc[i] - = force_const_mem (GET_MODE (x), x); + = force_const_mem (GET_MODE (SET_DEST (set)), x); } else continue; @@ -1205,33 +1204,21 @@ reload (first, global, dumpfile) /* Note that there is a continue statement above. */ } - /* If we have caller-saves, perform register elimination in the - save area addresses and see if caller-save will need a spill register. - If it will and we don't already have a need of class BASE_REG_CLASS, - create such a need. If we didn't need caller-saves before this - pass, allocate the save area and show something changed. */ + /* If we have caller-saves, set up the save areas and see if caller-save + will need a spill register. If it will and we don't already have a + need of class BASE_REG_CLASS, create such a need. */ - if (caller_save_needed) + if (caller_save_needed + && 0 != (caller_save_needs_spill + = ! setup_save_areas (&something_changed)) + && max_needs[(int) BASE_REG_CLASS] == 0) { - if (! old_caller_save_needed) - { - allocate_save_areas (); - something_changed = 1; - } + register enum reg_class *p + = reg_class_superclasses[(int) BASE_REG_CLASS]; - old_caller_save_needed = 1; - - caller_save_needs_spill = ! elim_save_addrs (); - if (caller_save_needs_spill - && max_needs[(int) BASE_REG_CLASS] == 0) - { - register enum reg_class *p - = reg_class_superclasses[(int) BASE_REG_CLASS]; - - max_needs[(int) BASE_REG_CLASS] = 1; - while (*p != LIM_REG_CLASSES) - max_needs[(int) *p++] += 1; - } + max_needs[(int) BASE_REG_CLASS] = 1; + while (*p != LIM_REG_CLASSES) + max_needs[(int) *p++] += 1; } /* Now deduct from the needs for the registers already @@ -1243,7 +1230,7 @@ reload (first, global, dumpfile) /* First find all regs alone in their class and count them (if desired) for non-groups. We would be screwed if a group took the only reg in a class - for which a non-group reload ius needed. + for which a non-group reload is needed. (Note there is still a bug; if a class has 2 regs, both could be stolen by groups and we would lose the same way. With luck, no machine will need a nongroup in a 2-reg class.) */ @@ -4403,6 +4390,7 @@ emit_reload_insns (insn) rtx oldequiv = 0; enum machine_mode mode; rtx where; + rtx reload_insn; /* Determine the mode to reload in. This is very tricky because we have three to choose from. @@ -4615,12 +4603,15 @@ emit_reload_insns (insn) enum insn_code icode; /* If we have a secondary reload, pick up the secondary register - and icode, if any. If OLDEQUIV and OLD are different, - recompute whether or not we still need a secondary register - and what the icode should be. If we still need a secondary - register and the class or icode is different, go back to - reloading from OLD if using OLDEQUIV means that we got the - wrong type of register. */ + and icode, if any. If OLDEQUIV and OLD are different or + if this is an in-out reload, recompute whether or not we + still need a secondary register and what the icode should + be. If we still need a secondary register and the class or + icode is different, go back to reloading from OLD if using + OLDEQUIV means that we got the wrong type of register. We + cannot have different class or icode due to an in-out reload + because we don't make such reloads when both the input and + output need secondary reload registers. */ if (reload_secondary_reload[j] >= 0) { @@ -4628,7 +4619,8 @@ emit_reload_insns (insn) second_reload_reg = reload_reg_rtx[secondary_reload]; icode = reload_secondary_icode[j]; - if (old != oldequiv && ! rtx_equal_p (old, oldequiv)) + if ((old != oldequiv && ! rtx_equal_p (old, oldequiv)) + || (reload_in[j] != 0 && reload_out[j] != 0)) { enum reg_class new_class = SECONDARY_INPUT_RELOAD_CLASS (reload_reg_class[j], @@ -4683,10 +4675,12 @@ emit_reload_insns (insn) { if (icode != CODE_FOR_nothing) { - emit_insn_before (GEN_FCN (icode) - (reloadreg, oldequiv, - second_reload_reg), - where); + reload_insn = emit_insn_before (GEN_FCN (icode) + (reloadreg, oldequiv, + second_reload_reg), + where); + if (this_reload_insn == 0) + this_reload_insn = reload_insn; special = 1; } else @@ -4701,15 +4695,22 @@ emit_reload_insns (insn) rtx third_reload_reg = reload_reg_rtx[reload_secondary_reload[secondary_reload]]; - emit_insn_before ((GEN_FCN (tertiary_icode) - (second_reload_reg, oldequiv, - third_reload_reg)), - where); + reload_insn + = emit_insn_before ((GEN_FCN (tertiary_icode) + (second_reload_reg, + oldequiv, + third_reload_reg)), + where); + if (this_reload_insn == 0) + this_reload_insn = reload_insn; } else { - gen_input_reload (second_reload_reg, - oldequiv, where); + reload_insn + = gen_input_reload (second_reload_reg, + oldequiv, where); + if (this_reload_insn == 0) + this_reload_insn = reload_insn; oldequiv = second_reload_reg; } } @@ -4718,8 +4719,12 @@ emit_reload_insns (insn) #endif if (! special) - this_reload_insn = gen_input_reload (reloadreg, - oldequiv, where); + { + reload_insn = gen_input_reload (reloadreg, + oldequiv, where); + if (this_reload_insn == 0) + this_reload_insn = reload_insn; + } #if defined(SECONDARY_INPUT_RELOAD_CLASS) && defined(PRESERVE_DEATH_INFO_REGNO_P) /* We may have to make a REG_DEAD note for the secondary reload @@ -5073,15 +5078,6 @@ emit_reload_insns (insn) new_spill_reg_store[reload_spill_index[j]] = store_insn; } - /* Now update spill_reg_store for the reloads of this insn. */ - /* Copy the elements that were updated in the loop above. */ - for (j = 0; j < n_reloads; j++) - { - int regno = reload_spill_index[j]; - if (regno >= 0) - spill_reg_store[regno] = new_spill_reg_store[regno]; - } - /* Move death notes from INSN to output-operand-address and output reload insns. */ #ifdef PRESERVE_DEATH_INFO_REGNO_P @@ -5126,7 +5122,10 @@ emit_reload_insns (insn) /* For all the spill regs newly reloaded in this instruction, record what they were reloaded from, so subsequent instructions - can inherit the reloads. */ + can inherit the reloads. + + Update spill_reg_store for the reloads of this insn. + Copy the elements that were updated in the loop above. */ for (j = 0; j < n_reloads; j++) { @@ -5136,6 +5135,7 @@ emit_reload_insns (insn) /* I is nonneg if this reload used one of the spill regs. If reload_reg_rtx[r] is 0, this is an optional reload that we opted to ignore. */ + if (i >= 0 && reload_reg_rtx[r] != 0) { /* First, clear out memory of what used to be in this spill reg. @@ -5154,7 +5154,10 @@ emit_reload_insns (insn) if (reload_out[r] != 0 && GET_CODE (reload_out[r]) == REG) { register int nregno = REGNO (reload_out[r]); + + spill_reg_store[i] = new_spill_reg_store[i]; reg_last_reload_reg[nregno] = reload_reg_rtx[r]; + for (k = 0; k < nr; k++) { reg_reloaded_contents[spill_reg_order[spill_regs[i] + k]] @@ -5162,6 +5165,7 @@ emit_reload_insns (insn) reg_reloaded_insn[spill_reg_order[spill_regs[i] + k]] = insn; } } + /* Maybe the spill reg contains a copy of reload_in. */ else if (reload_out[r] == 0 && reload_in[r] != 0 @@ -5186,6 +5190,12 @@ emit_reload_insns (insn) reload_when_needed[r])) { reg_last_reload_reg[nregno] = reload_reg_rtx[r]; + + /* Unless we inherited this reload, show we haven't + recently done a store. */ + if (! reload_inherited[r]) + spill_reg_store[i] = 0; + for (k = 0; k < nr; k++) { reg_reloaded_contents[spill_reg_order[spill_regs[i] + k]] @@ -5214,7 +5224,7 @@ emit_reload_insns (insn) } /* Emit code before BEFORE_INSN to perform an input reload of IN to RELOADREG. - Returns last insn emitted. */ + Returns first insn emitted. */ rtx gen_input_reload (reloadreg, in, before_insn) @@ -5402,11 +5412,11 @@ delete_output_reload (insn, j, output_reload_insn) Search that range; see if any ref remains. */ for (i2 = PREV_INSN (insn); i2; i2 = PREV_INSN (i2)) { + rtx set = single_set (i2); + /* Uses which just store in the pseudo don't count, since if they are the only uses, they are dead. */ - if (GET_CODE (i2) == INSN - && GET_CODE (PATTERN (i2)) == SET - && SET_DEST (PATTERN (i2)) == reg) + if (set != 0 && SET_DEST (set) == reg) continue; if (GET_CODE (i2) == CODE_LABEL || GET_CODE (i2) == JUMP_INSN) @@ -5421,11 +5431,9 @@ delete_output_reload (insn, j, output_reload_insn) /* Delete the now-dead stores into this pseudo. */ for (i2 = PREV_INSN (insn); i2; i2 = PREV_INSN (i2)) { - /* Uses which just store in the pseudo don't count, - since if they are the only uses, they are dead. */ - if (GET_CODE (i2) == INSN - && GET_CODE (PATTERN (i2)) == SET - && SET_DEST (PATTERN (i2)) == reg) + rtx set = single_set (i2); + + if (set != 0 && SET_DEST (set) == reg) delete_insn (i2); if (GET_CODE (i2) == CODE_LABEL || GET_CODE (i2) == JUMP_INSN) @@ -5593,7 +5601,8 @@ constraint_accepts_reg_p (string, reg) } } -/* Return the number of places FIND appears within X. */ +/* Return the number of places FIND appears within X, but don't count + an occurrence if some SET_DEST is FIND. */ static int count_occurrences (x, find) @@ -5622,6 +5631,11 @@ count_occurrences (x, find) case PC: case CC0: return 0; + + case SET: + if (SET_DEST (x) == find) + return count_occurrences (SET_SRC (x), find); + break; } format_ptr = GET_RTX_FORMAT (code); -- 2.30.2