rtx_iv Struct Reference

#include <cfgloop.h>

Data Fields
rtx	base
rtx	step
enum iv_extend_code	extend
rtx	delta
rtx	mult
enum machine_mode	extend_mode
enum machine_mode	mode
unsigned	first_special: 1

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Detailed Description

Induction variable analysis.   

The description of induction variable.  The things are a bit complicated
   due to need to handle subregs and extends.  The value of the object described
   by it can be obtained as follows (all computations are done in extend_mode):

   Value in i-th iteration is
     delta + mult * extend_{extend_mode} (subreg_{mode} (base + i * step)).

   If first_special is true, the value in the first iteration is
     delta + mult * base

   If extend = UNKNOWN, first_special must be false, delta 0, mult 1 and value is
     subreg_{mode} (base + i * step)

   The get_iv_value function can be used to obtain these expressions.

   ??? Add a third mode field that would specify the mode in that inner
   computation is done, which would enable it to be different from the
   outer one?   

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Field Documentation

rtx rtx_iv::base

Referenced by canonicalize_iv_subregs(), dump_iv_info(), get_iv_value(), iv_add(), iv_analyze_biv(), iv_analyze_def(), iv_analyze_expr(), iv_constant(), iv_extend(), iv_mult(), iv_neg(), iv_number_of_iterations(), iv_shift(), iv_subreg(), and shorten_into_mode().

rtx rtx_iv::delta

Referenced by canonicalize_iv_subregs(), dump_iv_info(), get_iv_value(), iv_add(), iv_analyze_biv(), iv_constant(), iv_extend(), iv_mult(), iv_neg(), iv_number_of_iterations(), iv_shift(), and iv_subreg().

enum iv_extend_code rtx_iv::extend

Referenced by canonicalize_iv_subregs(), dump_iv_info(), get_iv_value(), iv_add(), iv_analyze_biv(), iv_constant(), iv_extend(), iv_mult(), iv_neg(), iv_shift(), iv_subreg(), and shorten_into_mode().

enum machine_mode rtx_iv::extend_mode

Referenced by analyze_iv_to_split_insn(), canonicalize_iv_subregs(), dump_iv_info(), get_iv_value(), iv_add(), iv_analyze_biv(), iv_analyze_expr(), iv_constant(), iv_extend(), iv_mult(), iv_neg(), iv_number_of_iterations(), iv_shift(), iv_subreg(), and shorten_into_mode().

unsigned rtx_iv::first_special

Referenced by canonicalize_iv_subregs(), dump_iv_info(), get_iv_value(), iv_analyze_biv(), iv_constant(), iv_extend(), iv_subreg(), and may_unswitch_on().

enum machine_mode rtx_iv::mode

Referenced by analyze_iv_to_split_insn(), canon_condition(), canonicalize_iv_subregs(), dump_iv_info(), get_iv_value(), implies_p(), iv_add(), iv_analyze_biv(), iv_analyze_def(), iv_analyze_expr(), iv_constant(), iv_extend(), iv_number_of_iterations(), iv_subreg(), may_unswitch_on(), and shorten_into_mode().

rtx rtx_iv::mult

Referenced by canonicalize_iv_subregs(), dump_iv_info(), get_iv_value(), iv_analyze_biv(), iv_constant(), iv_extend(), iv_mult(), iv_neg(), iv_shift(), and iv_subreg().

rtx rtx_iv::step

Referenced by analyze_iv_to_split_insn(), biv_p(), canonicalize_iv_subregs(), dump_iv_info(), get_iv_value(), iv_add(), iv_analyze_biv(), iv_analyze_def(), iv_analyze_expr(), iv_constant(), iv_extend(), iv_mult(), iv_neg(), iv_number_of_iterations(), iv_shift(), iv_subreg(), and may_unswitch_on().

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The documentation for this struct was generated from the following file:

• cfgloop.h