static void final_reg_note_copy PARAMS ((rtx, struct inline_remap *));
static void copy_loop_body PARAMS ((rtx, rtx, struct inline_remap *, rtx, int,
enum unroll_types, rtx, rtx, rtx, rtx));
-static void iteration_info PARAMS ((const struct loop *, rtx, rtx *, rtx *));
static int find_splittable_regs PARAMS ((const struct loop *,
enum unroll_types, rtx, int));
static int find_splittable_givs PARAMS ((const struct loop *,
return 0;
}
- /* Note that iteration_info biases the initial value for GIV iterators
+ /* Note that loop_iterations biases the initial value for GIV iterators
such as "while (i-- > 0)" so that we can calculate the number of
iterations just like for BIV iterators.
return result;
}
-/* Determine the initial value of the iteration variable, and the amount
- that it is incremented each loop. Use the tables constructed by
- the strength reduction pass to calculate these values.
-
- Initial_value and/or increment are set to zero if their values could not
- be calculated. */
-
-static void
-iteration_info (loop, iteration_var, initial_value, increment)
- const struct loop *loop ATTRIBUTE_UNUSED;
- rtx iteration_var, *initial_value, *increment;
-{
- struct iv_class *bl;
-
- /* Clear the result values, in case no answer can be found. */
- *initial_value = 0;
- *increment = 0;
-
- /* The iteration variable can be either a giv or a biv. Check to see
- which it is, and compute the variable's initial value, and increment
- value if possible. */
-
- /* If this is a new register, can't handle it since we don't have any
- reg_iv_type entry for it. */
- if ((unsigned) REGNO (iteration_var) >= reg_iv_type->num_elements)
- {
- if (loop_dump_stream)
- fprintf (loop_dump_stream,
- "Loop unrolling: No reg_iv_type entry for iteration var.\n");
- return;
- }
-
- /* Reject iteration variables larger than the host wide int size, since they
- could result in a number of iterations greater than the range of our
- `unsigned HOST_WIDE_INT' variable loop_info->n_iterations. */
- else if ((GET_MODE_BITSIZE (GET_MODE (iteration_var))
- > HOST_BITS_PER_WIDE_INT))
- {
- if (loop_dump_stream)
- fprintf (loop_dump_stream,
- "Loop unrolling: Iteration var rejected because mode too large.\n");
- return;
- }
- else if (GET_MODE_CLASS (GET_MODE (iteration_var)) != MODE_INT)
- {
- if (loop_dump_stream)
- fprintf (loop_dump_stream,
- "Loop unrolling: Iteration var not an integer.\n");
- return;
- }
- else if (REG_IV_TYPE (REGNO (iteration_var)) == BASIC_INDUCT)
- {
- /* When reg_iv_type / reg_iv_info is resized for biv increments
- that are turned into givs, reg_biv_class is not resized.
- So check here that we don't make an out-of-bounds access. */
- if (REGNO (iteration_var) >= max_reg_before_loop)
- abort ();
-
- /* Grab initial value, only useful if it is a constant. */
- bl = reg_biv_class[REGNO (iteration_var)];
- *initial_value = bl->initial_value;
-
- *increment = biv_total_increment (bl);
- }
- else if (REG_IV_TYPE (REGNO (iteration_var)) == GENERAL_INDUCT)
- {
- HOST_WIDE_INT offset = 0;
- struct induction *v = REG_IV_INFO (REGNO (iteration_var));
- rtx biv_initial_value;
-
- if (REGNO (v->src_reg) >= max_reg_before_loop)
- abort ();
-
- bl = reg_biv_class[REGNO (v->src_reg)];
-
- /* Increment value is mult_val times the increment value of the biv. */
-
- *increment = biv_total_increment (bl);
- if (*increment)
- {
- struct induction *biv_inc;
-
- *increment
- = fold_rtx_mult_add (v->mult_val, *increment, const0_rtx, v->mode);
- /* The caller assumes that one full increment has occured at the
- first loop test. But that's not true when the biv is incremented
- after the giv is set (which is the usual case), e.g.:
- i = 6; do {;} while (i++ < 9) .
- Therefore, we bias the initial value by subtracting the amount of
- the increment that occurs between the giv set and the giv test. */
- for (biv_inc = bl->biv; biv_inc; biv_inc = biv_inc->next_iv)
- {
- if (loop_insn_first_p (v->insn, biv_inc->insn))
- offset -= INTVAL (biv_inc->add_val);
- }
- offset *= INTVAL (v->mult_val);
- }
- if (loop_dump_stream)
- fprintf (loop_dump_stream,
- "Loop unrolling: Giv iterator, initial value bias %ld.\n",
- (long) offset);
-
- /* Initial value is mult_val times the biv's initial value plus
- add_val. Only useful if it is a constant. */
- biv_initial_value = extend_value_for_giv (v, bl->initial_value);
- *initial_value
- = fold_rtx_mult_add (v->mult_val,
- plus_constant (biv_initial_value, offset),
- v->add_val, v->mode);
- }
- else
- {
- if (loop_dump_stream)
- fprintf (loop_dump_stream,
- "Loop unrolling: Not basic or general induction var.\n");
- return;
- }
-}
-
/* For each biv and giv, determine whether it can be safely split into
a different variable for each unrolled copy of the loop body. If it
return NULL_RTX;
}
-/* Calculate the number of loop iterations. Returns the exact number of loop
- iterations if it can be calculated, otherwise returns zero. */
+
+/* Determine the loop iterator and calculate the number of loop
+ iterations. Returns the exact number of loop iterations if it can
+ be calculated, otherwise returns zero. */
unsigned HOST_WIDE_INT
loop_iterations (loop)
rtx last_loop_insn;
rtx reg_term;
struct loop_info *loop_info = LOOP_INFO (loop);
+ struct iv_class *bl;
loop_info->n_iterations = 0;
loop_info->initial_value = 0;
loop_info->increment = 0;
loop_info->iteration_var = 0;
loop_info->unroll_number = 1;
+ loop_info->iv = 0;
/* We used to use prev_nonnote_insn here, but that fails because it might
accidentally get the branch for a contained loop if the branch for this
&& ! REG_USERVAR_P (iteration_var))
abort ();
- iteration_info (loop, iteration_var, &initial_value, &increment);
+ /* Determine the initial value of the iteration variable, and the amount
+ that it is incremented each loop. Use the tables constructed by
+ the strength reduction pass to calculate these values. */
+
+ /* Clear the result values, in case no answer can be found. */
+ initial_value = 0;
+ increment = 0;
+
+ /* The iteration variable can be either a giv or a biv. Check to see
+ which it is, and compute the variable's initial value, and increment
+ value if possible. */
+
+ /* If this is a new register, can't handle it since we don't have any
+ reg_iv_type entry for it. */
+ if ((unsigned) REGNO (iteration_var) >= reg_iv_type->num_elements)
+ {
+ if (loop_dump_stream)
+ fprintf (loop_dump_stream,
+ "Loop iterations: No reg_iv_type entry for iteration var.\n");
+ return 0;
+ }
+
+ /* Reject iteration variables larger than the host wide int size, since they
+ could result in a number of iterations greater than the range of our
+ `unsigned HOST_WIDE_INT' variable loop_info->n_iterations. */
+ else if ((GET_MODE_BITSIZE (GET_MODE (iteration_var))
+ > HOST_BITS_PER_WIDE_INT))
+ {
+ if (loop_dump_stream)
+ fprintf (loop_dump_stream,
+ "Loop iterations: Iteration var rejected because mode too large.\n");
+ return 0;
+ }
+ else if (GET_MODE_CLASS (GET_MODE (iteration_var)) != MODE_INT)
+ {
+ if (loop_dump_stream)
+ fprintf (loop_dump_stream,
+ "Loop iterations: Iteration var not an integer.\n");
+ return 0;
+ }
+ else if (REG_IV_TYPE (REGNO (iteration_var)) == BASIC_INDUCT)
+ {
+ /* When reg_iv_type / reg_iv_info is resized for biv increments
+ that are turned into givs, reg_biv_class is not resized.
+ So check here that we don't make an out-of-bounds access. */
+ if (REGNO (iteration_var) >= max_reg_before_loop)
+ abort ();
+
+ /* Grab initial value, only useful if it is a constant. */
+ bl = reg_biv_class[REGNO (iteration_var)];
+ initial_value = bl->initial_value;
+
+ increment = biv_total_increment (bl);
+ }
+ else if (REG_IV_TYPE (REGNO (iteration_var)) == GENERAL_INDUCT)
+ {
+ HOST_WIDE_INT offset = 0;
+ struct induction *v = REG_IV_INFO (REGNO (iteration_var));
+ rtx biv_initial_value;
+
+ if (REGNO (v->src_reg) >= max_reg_before_loop)
+ abort ();
+
+ bl = reg_biv_class[REGNO (v->src_reg)];
+
+ /* Increment value is mult_val times the increment value of the biv. */
+
+ increment = biv_total_increment (bl);
+ if (increment)
+ {
+ struct induction *biv_inc;
+
+ increment
+ = fold_rtx_mult_add (v->mult_val, increment, const0_rtx, v->mode);
+ /* The caller assumes that one full increment has occured at the
+ first loop test. But that's not true when the biv is incremented
+ after the giv is set (which is the usual case), e.g.:
+ i = 6; do {;} while (i++ < 9) .
+ Therefore, we bias the initial value by subtracting the amount of
+ the increment that occurs between the giv set and the giv test. */
+ for (biv_inc = bl->biv; biv_inc; biv_inc = biv_inc->next_iv)
+ {
+ if (loop_insn_first_p (v->insn, biv_inc->insn))
+ offset -= INTVAL (biv_inc->add_val);
+ }
+ offset *= INTVAL (v->mult_val);
+ }
+ if (loop_dump_stream)
+ fprintf (loop_dump_stream,
+ "Loop iterations: Giv iterator, initial value bias %ld.\n",
+ (long) offset);
+
+ /* Initial value is mult_val times the biv's initial value plus
+ add_val. Only useful if it is a constant. */
+ biv_initial_value = extend_value_for_giv (v, bl->initial_value);
+ initial_value
+ = fold_rtx_mult_add (v->mult_val,
+ plus_constant (biv_initial_value, offset),
+ v->add_val, v->mode);
+ }
+ else
+ {
+ if (loop_dump_stream)
+ fprintf (loop_dump_stream,
+ "Loop iterations: Not basic or general induction var.\n");
+ return 0;
+ }
if (initial_value == 0)
- /* iteration_info already printed a message. */
return 0;
unsigned_p = 0;
loop_info->increment = increment;
loop_info->iteration_var = iteration_var;
loop_info->comparison_code = comparison_code;
+ loop_info->iv = bl;
/* Try to determine the iteration count for loops such
as (for i = init; i < init + const; i++). When running the
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