diff options
| -rw-r--r-- | gcc/ChangeLog | 15 | ||||
| -rw-r--r-- | gcc/combine.c | 424 |
2 files changed, 214 insertions, 225 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 5b137ab..5891803 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,18 @@ +2004-05-12 Paolo Bonzini <bonzini@gnu.org> + + Replace several arrays with a struct of arrays. + * combine.c (struct reg_stat): New. + (init_reg_last_arrays): Renamed to... + (init_reg_last): ...this. Callers adjusted. + (reg_stat): New. + (combine_instructions): Allocate it and use it. + (reg_last_death, reg_last_set, reg_last_set_value, + reg_last_set_label, reg_last_set_table_tick, + reg_last_set_invalid, reg_nonzero_bits, reg_sign_bit_copies, + reg_last_set_mode, reg_last_set_nonzero_bits, + reg_last_set_sign_bit_copies): Replace throughout + with items of reg_stat. + 2004-05-11 Kaz Kojima <kkojima@gcc.gnu.org> PR optimization/15100 diff --git a/gcc/combine.c b/gcc/combine.c index 49b486e..7765374 100644 --- a/gcc/combine.c +++ b/gcc/combine.c @@ -143,13 +143,103 @@ static int max_uid_cuid; static unsigned int combine_max_regno; -/* Record last point of death of (hard or pseudo) register n. */ +struct reg_stat { + /* Record last point of death of (hard or pseudo) register n. */ + rtx last_death; -static rtx *reg_last_death; + /* Record last point of modification of (hard or pseudo) register n. */ + rtx last_set; -/* Record last point of modification of (hard or pseudo) register n. */ + /* The next group of fields allows the recording of the last value assigned + to (hard or pseudo) register n. We use this information to see if an + operation being processed is redundant given a prior operation performed + on the register. For example, an `and' with a constant is redundant if + all the zero bits are already known to be turned off. -static rtx *reg_last_set; + We use an approach similar to that used by cse, but change it in the + following ways: + + (1) We do not want to reinitialize at each label. + (2) It is useful, but not critical, to know the actual value assigned + to a register. Often just its form is helpful. + + Therefore, we maintain the following fields: + + last_set_value the last value assigned + last_set_label records the value of label_tick when the + register was assigned + last_set_table_tick records the value of label_tick when a + value using the register is assigned + last_set_invalid set to nonzero when it is not valid + to use the value of this register in some + register's value + + To understand the usage of these tables, it is important to understand + the distinction between the value in last_set_value being valid and + the register being validly contained in some other expression in the + table. + + (The next two parameters are out of date). + + reg_stat[i].last_set_value is valid if it is nonzero, and either + reg_n_sets[i] is 1 or reg_stat[i].last_set_label == label_tick. + + Register I may validly appear in any expression returned for the value + of another register if reg_n_sets[i] is 1. It may also appear in the + value for register J if reg_stat[j].last_set_invalid is zero, or + reg_stat[i].last_set_label < reg_stat[j].last_set_label. + + If an expression is found in the table containing a register which may + not validly appear in an expression, the register is replaced by + something that won't match, (clobber (const_int 0)). */ + + /* Record last value assigned to (hard or pseudo) register n. */ + + rtx last_set_value; + + /* Record the value of label_tick when an expression involving register n + is placed in last_set_value. */ + + int last_set_table_tick; + + /* Record the value of label_tick when the value for register n is placed in + last_set_value. */ + + int last_set_label; + + /* These fields are maintained in parallel with last_set_value and are + used to store the mode in which the register was last set, te bits + that were known to be zero when it was last set, and the number of + sign bits copies it was known to have when it was last set. */ + + unsigned HOST_WIDE_INT last_set_nonzero_bits; + char last_set_sign_bit_copies; + ENUM_BITFIELD(machine_mode) last_set_mode : 8; + + /* Set nonzero if references to register n in expressions should not be + used. last_set_invalid is set nonzero when this register is being + assigned to and last_set_table_tick == label_tick. */ + + char last_set_invalid; + + /* Some registers that are set more than once and used in more than one + basic block are nevertheless always set in similar ways. For example, + a QImode register may be loaded from memory in two places on a machine + where byte loads zero extend. + + We record in the following fields if a register has some leading bits + that are always equal to the sign bit, and what we know about the + nonzero bits of a register, specifically which bits are known to be + zero. + + If an entry is zero, it means that we don't know anything special. */ + + unsigned char sign_bit_copies; + + unsigned HOST_WIDE_INT nonzero_bits; +}; + +static struct reg_stat *reg_stat; /* Record the cuid of the last insn that invalidated memory (anything that writes memory, and subroutine calls, but not pushes). */ @@ -197,110 +287,23 @@ static basic_block this_basic_block; those blocks as starting points. */ static sbitmap refresh_blocks; -/* The next group of arrays allows the recording of the last value assigned - to (hard or pseudo) register n. We use this information to see if an - operation being processed is redundant given a prior operation performed - on the register. For example, an `and' with a constant is redundant if - all the zero bits are already known to be turned off. - - We use an approach similar to that used by cse, but change it in the - following ways: - - (1) We do not want to reinitialize at each label. - (2) It is useful, but not critical, to know the actual value assigned - to a register. Often just its form is helpful. - - Therefore, we maintain the following arrays: - - reg_last_set_value the last value assigned - reg_last_set_label records the value of label_tick when the - register was assigned - reg_last_set_table_tick records the value of label_tick when a - value using the register is assigned - reg_last_set_invalid set to nonzero when it is not valid - to use the value of this register in some - register's value - - To understand the usage of these tables, it is important to understand - the distinction between the value in reg_last_set_value being valid - and the register being validly contained in some other expression in the - table. - - Entry I in reg_last_set_value is valid if it is nonzero, and either - reg_n_sets[i] is 1 or reg_last_set_label[i] == label_tick. - - Register I may validly appear in any expression returned for the value - of another register if reg_n_sets[i] is 1. It may also appear in the - value for register J if reg_last_set_label[i] < reg_last_set_label[j] or - reg_last_set_invalid[j] is zero. - - If an expression is found in the table containing a register which may - not validly appear in an expression, the register is replaced by - something that won't match, (clobber (const_int 0)). - - reg_last_set_invalid[i] is set nonzero when register I is being assigned - to and reg_last_set_table_tick[i] == label_tick. */ - -/* Record last value assigned to (hard or pseudo) register n. */ - -static rtx *reg_last_set_value; - -/* Record the value of label_tick when the value for register n is placed in - reg_last_set_value[n]. */ - -static int *reg_last_set_label; - -/* Record the value of label_tick when an expression involving register n - is placed in reg_last_set_value. */ - -static int *reg_last_set_table_tick; - -/* Set nonzero if references to register n in expressions should not be - used. */ - -static char *reg_last_set_invalid; - /* Incremented for each label. */ static int label_tick; -/* Some registers that are set more than once and used in more than one - basic block are nevertheless always set in similar ways. For example, - a QImode register may be loaded from memory in two places on a machine - where byte loads zero extend. - - We record in the following array what we know about the nonzero - bits of a register, specifically which bits are known to be zero. - - If an entry is zero, it means that we don't know anything special. */ - -static unsigned HOST_WIDE_INT *reg_nonzero_bits; - -/* Mode used to compute significance in reg_nonzero_bits. It is the largest - integer mode that can fit in HOST_BITS_PER_WIDE_INT. */ +/* Mode used to compute significance in reg_stat[].nonzero_bits. It is the + largest integer mode that can fit in HOST_BITS_PER_WIDE_INT. */ static enum machine_mode nonzero_bits_mode; -/* Nonzero if we know that a register has some leading bits that are always - equal to the sign bit. */ - -static unsigned char *reg_sign_bit_copies; - -/* Nonzero when reg_nonzero_bits and reg_sign_bit_copies can be safely used. - It is zero while computing them and after combine has completed. This - former test prevents propagating values based on previously set values, - which can be incorrect if a variable is modified in a loop. */ +/* Nonzero when reg_stat[].nonzero_bits and reg_stat[].sign_bit_copies can + be safely used. It is zero while computing them and after combine has + completed. This former test prevents propagating values based on + previously set values, which can be incorrect if a variable is modified + in a loop. */ static int nonzero_sign_valid; -/* These arrays are maintained in parallel with reg_last_set_value - and are used to store the mode in which the register was last set, - the bits that were known to be zero when it was last set, and the - number of sign bits copies it was known to have when it was last set. */ - -static enum machine_mode *reg_last_set_mode; -static unsigned HOST_WIDE_INT *reg_last_set_nonzero_bits; -static char *reg_last_set_sign_bit_copies; /* Record one modification to rtl structure to be undone by storing old_contents into *where. @@ -336,7 +339,7 @@ static int n_occurrences; static void do_SUBST (rtx *, rtx); static void do_SUBST_INT (int *, int); -static void init_reg_last_arrays (void); +static void init_reg_last (void); static void setup_incoming_promotions (void); static void set_nonzero_bits_and_sign_copies (rtx, rtx, void *); static int cant_combine_insn_p (rtx); @@ -523,20 +526,7 @@ combine_instructions (rtx f, unsigned int nregs) See comments in gen_lowpart_for_combine. */ gen_lowpart = gen_lowpart_for_combine; - reg_nonzero_bits = xcalloc (nregs, sizeof (unsigned HOST_WIDE_INT)); - reg_sign_bit_copies = xcalloc (nregs, sizeof (unsigned char)); - - reg_last_death = xmalloc (nregs * sizeof (rtx)); - reg_last_set = xmalloc (nregs * sizeof (rtx)); - reg_last_set_value = xmalloc (nregs * sizeof (rtx)); - reg_last_set_table_tick = xmalloc (nregs * sizeof (int)); - reg_last_set_label = xmalloc (nregs * sizeof (int)); - reg_last_set_invalid = xmalloc (nregs * sizeof (char)); - reg_last_set_mode = xmalloc (nregs * sizeof (enum machine_mode)); - reg_last_set_nonzero_bits = xmalloc (nregs * sizeof (HOST_WIDE_INT)); - reg_last_set_sign_bit_copies = xmalloc (nregs * sizeof (char)); - - init_reg_last_arrays (); + reg_stat = xcalloc (nregs, sizeof (struct reg_stat)); init_recog_no_volatile (); @@ -551,8 +541,8 @@ combine_instructions (rtx f, unsigned int nregs) nonzero_bits_mode = mode_for_size (HOST_BITS_PER_WIDE_INT, MODE_INT, 0); - /* Don't use reg_nonzero_bits when computing it. This can cause problems - when, for example, we have j <<= 1 in a loop. */ + /* Don't use reg_stat[].nonzero_bits when computing it. This can cause + problems when, for example, we have j <<= 1 in a loop. */ nonzero_sign_valid = 0; @@ -605,7 +595,7 @@ combine_instructions (rtx f, unsigned int nregs) label_tick = 1; last_call_cuid = 0; mem_last_set = 0; - init_reg_last_arrays (); + init_reg_last (); setup_incoming_promotions (); FOR_EACH_BB (this_basic_block) @@ -768,17 +758,7 @@ combine_instructions (rtx f, unsigned int nregs) /* Clean up. */ sbitmap_free (refresh_blocks); - free (reg_nonzero_bits); - free (reg_sign_bit_copies); - free (reg_last_death); - free (reg_last_set); - free (reg_last_set_value); - free (reg_last_set_table_tick); - free (reg_last_set_label); - free (reg_last_set_invalid); - free (reg_last_set_mode); - free (reg_last_set_nonzero_bits); - free (reg_last_set_sign_bit_copies); + free (reg_stat); free (uid_cuid); { @@ -805,22 +785,14 @@ combine_instructions (rtx f, unsigned int nregs) return new_direct_jump_p; } -/* Wipe the reg_last_xxx arrays in preparation for another pass. */ +/* Wipe the last_xxx fields of reg_stat in preparation for another pass. */ static void -init_reg_last_arrays (void) +init_reg_last (void) { - unsigned int nregs = combine_max_regno; - - memset (reg_last_death, 0, nregs * sizeof (rtx)); - memset (reg_last_set, 0, nregs * sizeof (rtx)); - memset (reg_last_set_value, 0, nregs * sizeof (rtx)); - memset (reg_last_set_table_tick, 0, nregs * sizeof (int)); - memset (reg_last_set_label, 0, nregs * sizeof (int)); - memset (reg_last_set_invalid, 0, nregs * sizeof (char)); - memset (reg_last_set_mode, 0, nregs * sizeof (enum machine_mode)); - memset (reg_last_set_nonzero_bits, 0, nregs * sizeof (HOST_WIDE_INT)); - memset (reg_last_set_sign_bit_copies, 0, nregs * sizeof (char)); + unsigned int i; + for (i = 0; i < combine_max_regno; i++) + memset (reg_stat + i, 0, offsetof (struct reg_stat, sign_bit_copies)); } /* Set up any promoted values for incoming argument registers. */ @@ -878,8 +850,8 @@ set_nonzero_bits_and_sign_copies (rtx x, rtx set, { if (set == 0 || GET_CODE (set) == CLOBBER) { - reg_nonzero_bits[REGNO (x)] = GET_MODE_MASK (GET_MODE (x)); - reg_sign_bit_copies[REGNO (x)] = 1; + reg_stat[REGNO (x)].nonzero_bits = GET_MODE_MASK (GET_MODE (x)); + reg_stat[REGNO (x)].sign_bit_copies = 1; return; } @@ -901,7 +873,7 @@ set_nonzero_bits_and_sign_copies (rtx x, rtx set, #ifdef SHORT_IMMEDIATES_SIGN_EXTEND /* If X is narrower than a word and SRC is a non-negative constant that would appear negative in the mode of X, - sign-extend it for use in reg_nonzero_bits because some + sign-extend it for use in reg_stat[].nonzero_bits because some machines (maybe most) will actually do the sign-extension and this is the conservative approach. @@ -920,18 +892,18 @@ set_nonzero_bits_and_sign_copies (rtx x, rtx set, #endif /* Don't call nonzero_bits if it cannot change anything. */ - if (reg_nonzero_bits[REGNO (x)] != ~(unsigned HOST_WIDE_INT) 0) - reg_nonzero_bits[REGNO (x)] + if (reg_stat[REGNO (x)].nonzero_bits != ~(unsigned HOST_WIDE_INT) 0) + reg_stat[REGNO (x)].nonzero_bits |= nonzero_bits (src, nonzero_bits_mode); num = num_sign_bit_copies (SET_SRC (set), GET_MODE (x)); - if (reg_sign_bit_copies[REGNO (x)] == 0 - || reg_sign_bit_copies[REGNO (x)] > num) - reg_sign_bit_copies[REGNO (x)] = num; + if (reg_stat[REGNO (x)].sign_bit_copies == 0 + || reg_stat[REGNO (x)].sign_bit_copies > num) + reg_stat[REGNO (x)].sign_bit_copies = num; } else { - reg_nonzero_bits[REGNO (x)] = GET_MODE_MASK (GET_MODE (x)); - reg_sign_bit_copies[REGNO (x)] = 1; + reg_stat[REGNO (x)].nonzero_bits = GET_MODE_MASK (GET_MODE (x)); + reg_stat[REGNO (x)].sign_bit_copies = 1; } } } @@ -1101,7 +1073,7 @@ can_combine_p (rtx insn, rtx i3, rtx pred ATTRIBUTE_UNUSED, rtx succ, does not use any registers whose values alter in between. However, If the insns are adjacent, a use can't cross a set even though we think it might (this can happen for a sequence of insns each setting - the same destination; reg_last_set of that register might point to + the same destination; last_set of that register might point to a NOTE). If INSN has a REG_EQUIV note, the register is always equivalent to the memory so the substitution is valid even if there are intervening stores. Also, don't move a volatile asm or @@ -2331,18 +2303,18 @@ try_combine (rtx i3, rtx i2, rtx i1, int *new_direct_jump_p) && GET_CODE (SET_DEST (XVECEXP (newpat, 0, 1))) != STRICT_LOW_PART && ! (temp = SET_DEST (XVECEXP (newpat, 0, 1)), (GET_CODE (temp) == REG - && reg_nonzero_bits[REGNO (temp)] != 0 + && reg_stat[REGNO (temp)].nonzero_bits != 0 && GET_MODE_BITSIZE (GET_MODE (temp)) < BITS_PER_WORD && GET_MODE_BITSIZE (GET_MODE (temp)) < HOST_BITS_PER_INT - && (reg_nonzero_bits[REGNO (temp)] + && (reg_stat[REGNO (temp)].nonzero_bits != GET_MODE_MASK (word_mode)))) && ! (GET_CODE (SET_DEST (XVECEXP (newpat, 0, 1))) == SUBREG && (temp = SUBREG_REG (SET_DEST (XVECEXP (newpat, 0, 1))), (GET_CODE (temp) == REG - && reg_nonzero_bits[REGNO (temp)] != 0 + && reg_stat[REGNO (temp)].nonzero_bits != 0 && GET_MODE_BITSIZE (GET_MODE (temp)) < BITS_PER_WORD && GET_MODE_BITSIZE (GET_MODE (temp)) < HOST_BITS_PER_INT - && (reg_nonzero_bits[REGNO (temp)] + && (reg_stat[REGNO (temp)].nonzero_bits != GET_MODE_MASK (word_mode))))) && ! reg_overlap_mentioned_p (SET_DEST (XVECEXP (newpat, 0, 1)), SET_SRC (XVECEXP (newpat, 0, 1))) @@ -2783,9 +2755,10 @@ try_combine (rtx i3, rtx i2, rtx i1, int *new_direct_jump_p) REG_N_SETS (regno)--; } - /* Update reg_nonzero_bits et al for any changes that may have been made - to this insn. The order of set_nonzero_bits_and_sign_copies() is - important. Because newi2pat can affect nonzero_bits of newpat */ + /* Update reg_stat[].nonzero_bits et al for any changes that may have + been made to this insn. The order of + set_nonzero_bits_and_sign_copies() is important. Because newi2pat + can affect nonzero_bits of newpat */ if (newi2pat) note_stores (newi2pat, set_nonzero_bits_and_sign_copies, NULL); note_stores (newpat, set_nonzero_bits_and_sign_copies, NULL); @@ -8171,17 +8144,17 @@ nonzero_bits1 (rtx x, enum machine_mode mode, rtx known_x, value. Otherwise, use the previously-computed global nonzero bits for this register. */ - if (reg_last_set_value[REGNO (x)] != 0 - && (reg_last_set_mode[REGNO (x)] == mode - || (GET_MODE_CLASS (reg_last_set_mode[REGNO (x)]) == MODE_INT + if (reg_stat[REGNO (x)].last_set_value != 0 + && (reg_stat[REGNO (x)].last_set_mode == mode + || (GET_MODE_CLASS (reg_stat[REGNO (x)].last_set_mode) == MODE_INT && GET_MODE_CLASS (mode) == MODE_INT)) - && (reg_last_set_label[REGNO (x)] == label_tick + && (reg_stat[REGNO (x)].last_set_label == label_tick || (REGNO (x) >= FIRST_PSEUDO_REGISTER && REG_N_SETS (REGNO (x)) == 1 && ! REGNO_REG_SET_P (ENTRY_BLOCK_PTR->next_bb->global_live_at_start, REGNO (x)))) - && INSN_CUID (reg_last_set[REGNO (x)]) < subst_low_cuid) - return reg_last_set_nonzero_bits[REGNO (x)] & nonzero; + && INSN_CUID (reg_stat[REGNO (x)].last_set) < subst_low_cuid) + return reg_stat[REGNO (x)].last_set_nonzero_bits & nonzero; tem = get_last_value (x); @@ -8190,8 +8163,8 @@ nonzero_bits1 (rtx x, enum machine_mode mode, rtx known_x, #ifdef SHORT_IMMEDIATES_SIGN_EXTEND /* If X is narrower than MODE and TEM is a non-negative constant that would appear negative in the mode of X, - sign-extend it for use in reg_nonzero_bits because some - machines (maybe most) will actually do the sign-extension + sign-extend it for use in reg_stat[].nonzero_bits because + some machines (maybe most) will actually do the sign-extension and this is the conservative approach. ??? For 2.5, try to tighten up the MD files in this regard @@ -8209,9 +8182,9 @@ nonzero_bits1 (rtx x, enum machine_mode mode, rtx known_x, #endif return nonzero_bits_with_known (tem, mode) & nonzero; } - else if (nonzero_sign_valid && reg_nonzero_bits[REGNO (x)]) + else if (nonzero_sign_valid && reg_stat[REGNO (x)].nonzero_bits) { - unsigned HOST_WIDE_INT mask = reg_nonzero_bits[REGNO (x)]; + unsigned HOST_WIDE_INT mask = reg_stat[REGNO (x)].nonzero_bits; if (GET_MODE_BITSIZE (GET_MODE (x)) < mode_width) /* We don't know anything about the upper bits. */ @@ -8667,23 +8640,23 @@ num_sign_bit_copies1 (rtx x, enum machine_mode mode, rtx known_x, return GET_MODE_BITSIZE (Pmode) - GET_MODE_BITSIZE (ptr_mode) + 1; #endif - if (reg_last_set_value[REGNO (x)] != 0 - && reg_last_set_mode[REGNO (x)] == mode - && (reg_last_set_label[REGNO (x)] == label_tick + if (reg_stat[REGNO (x)].last_set_value != 0 + && reg_stat[REGNO (x)].last_set_mode == mode + && (reg_stat[REGNO (x)].last_set_label == label_tick || (REGNO (x) >= FIRST_PSEUDO_REGISTER && REG_N_SETS (REGNO (x)) == 1 && ! REGNO_REG_SET_P (ENTRY_BLOCK_PTR->next_bb->global_live_at_start, REGNO (x)))) - && INSN_CUID (reg_last_set[REGNO (x)]) < subst_low_cuid) - return reg_last_set_sign_bit_copies[REGNO (x)]; + && INSN_CUID (reg_stat[REGNO (x)].last_set) < subst_low_cuid) + return reg_stat[REGNO (x)].last_set_sign_bit_copies; tem = get_last_value (x); if (tem != 0) return num_sign_bit_copies_with_known (tem, mode); - if (nonzero_sign_valid && reg_sign_bit_copies[REGNO (x)] != 0 + if (nonzero_sign_valid && reg_stat[REGNO (x)].sign_bit_copies != 0 && GET_MODE_BITSIZE (GET_MODE (x)) == bitwidth) - return reg_sign_bit_copies[REGNO (x)]; + return reg_stat[REGNO (x)].sign_bit_copies; break; case MEM: @@ -11367,7 +11340,7 @@ reversed_comparison (rtx exp, enum machine_mode mode, rtx op0, rtx op1) } /* Utility function for following routine. Called when X is part of a value - being stored into reg_last_set_value. Sets reg_last_set_table_tick + being stored into last_set_value. Sets last_set_table_tick for each register mentioned. Similar to mention_regs in cse.c */ static void @@ -11386,7 +11359,7 @@ update_table_tick (rtx x) unsigned int r; for (r = regno; r < endregno; r++) - reg_last_set_table_tick[r] = label_tick; + reg_stat[r].last_set_table_tick = label_tick; return; } @@ -11434,8 +11407,9 @@ update_table_tick (rtx x) /* Record that REG is set to VALUE in insn INSN. If VALUE is zero, we are saying that the register is clobbered and we no longer know its - value. If INSN is zero, don't update reg_last_set; this is only permitted - with VALUE also zero and is used to invalidate the register. */ + value. If INSN is zero, don't update reg_stat[].last_set; this is + only permitted with VALUE also zero and is used to invalidate the + register. */ static void record_value_for_reg (rtx reg, rtx insn, rtx value) @@ -11479,13 +11453,13 @@ record_value_for_reg (rtx reg, rtx insn, rtx value) for (i = regno; i < endregno; i++) { if (insn) - reg_last_set[i] = insn; + reg_stat[i].last_set = insn; - reg_last_set_value[i] = 0; - reg_last_set_mode[i] = 0; - reg_last_set_nonzero_bits[i] = 0; - reg_last_set_sign_bit_copies[i] = 0; - reg_last_death[i] = 0; + reg_stat[i].last_set_value = 0; + reg_stat[i].last_set_mode = 0; + reg_stat[i].last_set_nonzero_bits = 0; + reg_stat[i].last_set_sign_bit_copies = 0; + reg_stat[i].last_death = 0; } /* Mark registers that are being referenced in this value. */ @@ -11501,40 +11475,40 @@ record_value_for_reg (rtx reg, rtx insn, rtx value) for (i = regno; i < endregno; i++) { - reg_last_set_label[i] = label_tick; - if (value && reg_last_set_table_tick[i] == label_tick) - reg_last_set_invalid[i] = 1; + reg_stat[i].last_set_label = label_tick; + if (value && reg_stat[i].last_set_table_tick == label_tick) + reg_stat[i].last_set_invalid = 1; else - reg_last_set_invalid[i] = 0; + reg_stat[i].last_set_invalid = 0; } /* The value being assigned might refer to X (like in "x++;"). In that case, we must replace it with (clobber (const_int 0)) to prevent infinite loops. */ if (value && ! get_last_value_validate (&value, insn, - reg_last_set_label[regno], 0)) + reg_stat[regno].last_set_label, 0)) { value = copy_rtx (value); if (! get_last_value_validate (&value, insn, - reg_last_set_label[regno], 1)) + reg_stat[regno].last_set_label, 1)) value = 0; } /* For the main register being modified, update the value, the mode, the nonzero bits, and the number of sign bit copies. */ - reg_last_set_value[regno] = value; + reg_stat[regno].last_set_value = value; if (value) { enum machine_mode mode = GET_MODE (reg); subst_low_cuid = INSN_CUID (insn); - reg_last_set_mode[regno] = mode; + reg_stat[regno].last_set_mode = mode; if (GET_MODE_CLASS (mode) == MODE_INT && GET_MODE_BITSIZE (mode) <= HOST_BITS_PER_WIDE_INT) mode = nonzero_bits_mode; - reg_last_set_nonzero_bits[regno] = nonzero_bits (value, mode); - reg_last_set_sign_bit_copies[regno] + reg_stat[regno].last_set_nonzero_bits = nonzero_bits (value, mode); + reg_stat[regno].last_set_sign_bit_copies = num_sign_bit_copies (value, GET_MODE (reg)); } } @@ -11579,11 +11553,11 @@ record_dead_and_set_regs_1 (rtx dest, rtx setter, void *data) for the things done by INSN. This is the last thing done in processing INSN in the combiner loop. - We update reg_last_set, reg_last_set_value, reg_last_set_mode, - reg_last_set_nonzero_bits, reg_last_set_sign_bit_copies, reg_last_death, - and also the similar information mem_last_set (which insn most recently - modified memory) and last_call_cuid (which insn was the most recent - subroutine call). */ + We update reg_stat[], in particular fields last_set, last_set_value, + last_set_mode, last_set_nonzero_bits, last_set_sign_bit_copies, + last_death, and also the similar information mem_last_set (which insn + most recently modified memory) and last_call_cuid (which insn was the + most recent subroutine call). */ static void record_dead_and_set_regs (rtx insn) @@ -11603,7 +11577,7 @@ record_dead_and_set_regs (rtx insn) : 1); for (i = regno; i < endregno; i++) - reg_last_death[i] = insn; + reg_stat[i].last_death = insn; } else if (REG_NOTE_KIND (link) == REG_INC) record_value_for_reg (XEXP (link, 0), insn, NULL_RTX); @@ -11614,11 +11588,11 @@ record_dead_and_set_regs (rtx insn) for (i = 0; i < FIRST_PSEUDO_REGISTER; i++) if (TEST_HARD_REG_BIT (regs_invalidated_by_call, i)) { - reg_last_set_value[i] = 0; - reg_last_set_mode[i] = 0; - reg_last_set_nonzero_bits[i] = 0; - reg_last_set_sign_bit_copies[i] = 0; - reg_last_death[i] = 0; + reg_stat[i].last_set_value = 0; + reg_stat[i].last_set_mode = 0; + reg_stat[i].last_set_nonzero_bits = 0; + reg_stat[i].last_set_sign_bit_copies = 0; + reg_stat[i].last_death = 0; } last_call_cuid = mem_last_set = INSN_CUID (insn); @@ -11666,10 +11640,10 @@ record_promoted_value (rtx insn, rtx subreg) continue; } - if (reg_last_set[regno] == insn) + if (reg_stat[regno].last_set == insn) { if (SUBREG_PROMOTED_UNSIGNED_P (subreg) > 0) - reg_last_set_nonzero_bits[regno] &= GET_MODE_MASK (mode); + reg_stat[regno].last_set_nonzero_bits &= GET_MODE_MASK (mode); } if (GET_CODE (SET_SRC (set)) == REG) @@ -11739,14 +11713,14 @@ get_last_value_validate (rtx *loc, rtx insn, int tick, int replace) unsigned int j; for (j = regno; j < endregno; j++) - if (reg_last_set_invalid[j] + if (reg_stat[j].last_set_invalid /* If this is a pseudo-register that was only set once and not live at the beginning of the function, it is always valid. */ || (! (regno >= FIRST_PSEUDO_REGISTER && REG_N_SETS (regno) == 1 && (! REGNO_REG_SET_P (ENTRY_BLOCK_PTR->next_bb->global_live_at_start, regno))) - && reg_last_set_label[j] > tick)) + && reg_stat[j].last_set_label > tick)) { if (replace) *loc = gen_rtx_CLOBBER (GET_MODE (x), const0_rtx); @@ -11838,7 +11812,7 @@ get_last_value (rtx x) return 0; regno = REGNO (x); - value = reg_last_set_value[regno]; + value = reg_stat[regno].last_set_value; /* If we don't have a value, or if it isn't for this basic block and it's either a hard register, set more than once, or it's a live @@ -11851,7 +11825,7 @@ get_last_value (rtx x) block. */ if (value == 0 - || (reg_last_set_label[regno] != label_tick + || (reg_stat[regno].last_set_label != label_tick && (regno < FIRST_PSEUDO_REGISTER || REG_N_SETS (regno) != 1 || (REGNO_REG_SET_P @@ -11860,20 +11834,20 @@ get_last_value (rtx x) /* If the value was set in a later insn than the ones we are processing, we can't use it even if the register was only set once. */ - if (INSN_CUID (reg_last_set[regno]) >= subst_low_cuid) + if (INSN_CUID (reg_stat[regno].last_set) >= subst_low_cuid) return 0; /* If the value has all its registers valid, return it. */ - if (get_last_value_validate (&value, reg_last_set[regno], - reg_last_set_label[regno], 0)) + if (get_last_value_validate (&value, reg_stat[regno].last_set, + reg_stat[regno].last_set_label, 0)) return value; /* Otherwise, make a copy and replace any invalid register with (clobber (const_int 0)). If that fails for some reason, return 0. */ value = copy_rtx (value); - if (get_last_value_validate (&value, reg_last_set[regno], - reg_last_set_label[regno], 1)) + if (get_last_value_validate (&value, reg_stat[regno].last_set, + reg_stat[regno].last_set_label, 1)) return value; return 0; @@ -11902,8 +11876,8 @@ use_crosses_set_p (rtx x, int from_cuid) return 1; #endif for (; regno < endreg; regno++) - if (reg_last_set[regno] - && INSN_CUID (reg_last_set[regno]) > from_cuid) + if (reg_stat[regno].last_set + && INSN_CUID (reg_stat[regno].last_set) > from_cuid) return 1; return 0; } @@ -12163,7 +12137,7 @@ move_deaths (rtx x, rtx maybe_kill_insn, int from_cuid, rtx to_insn, if (code == REG) { unsigned int regno = REGNO (x); - rtx where_dead = reg_last_death[regno]; + rtx where_dead = reg_stat[regno].last_death; rtx before_dead, after_dead; /* Don't move the register if it gets killed in between from and to. */ @@ -12190,7 +12164,7 @@ move_deaths (rtx x, rtx maybe_kill_insn, int from_cuid, rtx to_insn, rtx note = remove_death (regno, where_dead); /* It is possible for the call above to return 0. This can occur - when reg_last_death points to I2 or I1 that we combined with. + when last_death points to I2 or I1 that we combined with. In that case make a new note. We must also check for the case where X is a hard register @@ -12803,14 +12777,14 @@ distribute_notes (rtx notes, rtx from_insn, rtx i3, rtx i2) || reg_bitfield_target_p (XEXP (note, 0), PATTERN (place))) { /* Unless the register previously died in PLACE, clear - reg_last_death. [I no longer understand why this is + last_death. [I no longer understand why this is being done.] */ - if (reg_last_death[regno] != place) - reg_last_death[regno] = 0; + if (reg_stat[regno].last_death != place) + reg_stat[regno].last_death = 0; place = 0; } else - reg_last_death[regno] = place; + reg_stat[regno].last_death = place; /* If this is a death note for a hard reg that is occupying multiple registers, ensure that we are still using all |