Data Structures
struct	queued_debug_insn_change
struct	value_data_entry
struct	value_data
struct	kill_set_value_data

Functions
static void	kill_value_one_regno (unsigned, struct value_data *)
static void	kill_value_regno (unsigned, unsigned, struct value_data *)
static void	kill_value (rtx, struct value_data *)
static void	set_value_regno (unsigned, enum machine_mode, struct value_data *)
static void	init_value_data (struct value_data *)
static void	kill_clobbered_value (rtx, const_rtx, void *)
static void	kill_set_value (rtx, const_rtx, void *)
static int	kill_autoinc_value (rtx , void )
static void	copy_value (rtx, rtx, struct value_data *)
static bool	mode_change_ok (enum machine_mode, enum machine_mode, unsigned int)
static rtx	maybe_mode_change (enum machine_mode, enum machine_mode, enum machine_mode, unsigned int, unsigned int)
static rtx	find_oldest_value_reg (enum reg_class, rtx, struct value_data *)
static bool	replace_oldest_value_reg (rtx , enum reg_class, rtx, struct value_data )
static bool	replace_oldest_value_addr (rtx , enum reg_class, enum machine_mode, addr_space_t, rtx, struct value_data )
static bool	replace_oldest_value_mem (rtx, rtx, struct value_data *)
static bool	copyprop_hardreg_forward_1 (basic_block, struct value_data *)
void	debug_value_data (struct value_data *)
static void	validate_value_data (struct value_data *)
static void	free_debug_insn_changes ()
static void	kill_value_one_regno ()
static void	kill_value_regno (unsigned int regno, unsigned int nregs, struct value_data *vd)
static void	kill_value ()
static void	set_value_regno (unsigned int regno, enum machine_mode mode, struct value_data *vd)
static void	init_value_data ()
static void	kill_clobbered_value ()
static void	kill_set_value ()
static int	kill_autoinc_value ()
static void	copy_value ()
static rtx	find_oldest_value_reg ()
static bool	replace_oldest_value_mem ()
static void	apply_debug_insn_changes ()
static int	cprop_find_used_regs_1 ()
static void	cprop_find_used_regs ()
static bool	copyprop_hardreg_forward_1 ()
static unsigned int	copyprop_hardreg_forward ()
DEBUG_FUNCTION void	debug_value_data ()
static void	validate_value_data ()
static bool	gate_handle_cprop ()
rtl_opt_pass *	make_pass_cprop_hardreg ()

Variables
static alloc_pool	debug_insn_changes_pool

Function Documentation

static void apply_debug_insn_changes ( )

static

   Apply all queued updates for DEBUG_INSNs that change some reg to
   register REGNO.

static void copy_value	(	rtx	,
		rtx	,
		struct value_data *
	)

static

static void copy_value ( )

static

   Assert that SRC has been copied to DEST.  Adjust the data structures
   to reflect that SRC contains an older copy of the shared value.

     ??? At present, it's possible to see noop sets.  It'd be nice if
     this were cleaned up beforehand...

     Do not propagate copies to the stack pointer, as that can leave
     memory accesses with no scheduling dependency on the stack update.

     Likewise with the frame pointer, if we're using one.

     Do not propagate copies to fixed or global registers, patterns
     can be relying to see particular fixed register or users can
     expect the chosen global register in asm.

     If SRC and DEST overlap, don't record anything.

     If SRC had no assigned mode (i.e. we didn't know it was live)
     assign it now and assume the value came from an input argument
     or somesuch.

     If we are narrowing the input to a smaller number of hard regs,
     and it is in big endian, we are really extracting a high part.
     Since we generally associate a low part of a value with the value itself,
     we must not do the same for the high part.
     Note we can still get low parts for the same mode combination through
     a two-step copy involving differently sized hard regs.
     Assume hard regs fr* are 32 bits bits each, while r* are 64 bits each:
     (set (reg:DI r0) (reg:DI fr0))
     (set (reg:SI fr2) (reg:SI r0))
     loads the low part of (reg:DI fr0) - i.e. fr1 - into fr2, while:
     (set (reg:SI fr2) (reg:SI fr0))
     loads the high part of (reg:DI fr0) into fr2.

     We can't properly represent the latter case in our tables, so don't
     record anything then.

     If SRC had been assigned a mode narrower than the copy, we can't
     link DEST into the chain, because not all of the pieces of the
     copy came from oldest_regno.

     Link DR at the end of the value chain used by SR.

static unsigned int copyprop_hardreg_forward ( )

static

   Main entry point for the forward copy propagation optimization.

         If a block has a single predecessor, that we've already
         processed, begin with the value data that was live at
         the end of the predecessor block.

         ??? Ought to use more intelligent queuing of blocks.

References df_analyze().

Referenced by validate_value_data().

static bool copyprop_hardreg_forward_1	(	basic_block	,
		struct value_data *
	)

static

static bool copyprop_hardreg_forward_1 ( )

static

   Perform the forward copy propagation on basic block BB.

         Simplify the code below by rewriting things to reflect
         matching constraints.  Also promote OP_OUT to OP_INOUT
         in predicated instructions.

         Apply changes to earlier DEBUG_INSNs if possible.

         For each earlyclobber operand, zap the value data.

         Within asms, a clobber cannot overlap inputs or outputs.
         I wouldn't think this were true for regular insns, but
         scan_rtx treats them like that...

         Kill all auto-incremented values.

         ??? REG_INC is useless, since stack pushes aren't done that way.

         Kill all early-clobbered operands.

         Special-case plain move instructions, since we may well
         be able to do the move from a different register class.

             If we are accessing SRC in some mode other that what we
             set it in, make sure that the replacement is valid.

                 And likewise, if we are narrowing on big endian the transformation
                 is also invalid.

             If the destination is also a register, try to find a source
             register in the same class.

                 We need to re-extract as validate_change clobbers
                 recog_data.

             Otherwise, try all valid registers and see if its valid.

                     We need to re-extract as validate_change clobbers
                     recog_data.

         For each input operand, replace a hard register with the
         eldest live copy that's in an appropriate register class.

             Don't scan match_operand here, since we've no reg class
             information to pass down.  Any operands that we could
             substitute in will be represented elsewhere.

             Don't replace in asms intentionally referencing hard regs.

             If we performed any replacement, update match_dups.

             If something changed, perhaps further changes to earlier
             DEBUG_INSNs can be applied.

         Clobber call-clobbered registers.

             If SET was seen in CALL_INSN_FUNCTION_USAGE, and SET_SRC
             of the SET isn't in regs_invalidated_by_call hard reg set,
             but instead among CLOBBERs on the CALL_INSN, we could wrongly
             assume the value in it is still live.

         Notice stores.

         Notice copies.

References operand_alternative::cl, operand_alternative::matches, OP_INOUT, OP_OUT, recog_data_d::operand_type, recog_data, and recog_op_alt.

static void cprop_find_used_regs ( )

static

   Called via note_uses, for all used registers in a real insn
   apply DEBUG_INSN changes that change registers to the used
   registers.

static int cprop_find_used_regs_1 ( )

static

   Called via for_each_rtx, for all used registers in a real
   insn apply DEBUG_INSN changes that change registers to the
   used register.

void debug_value_data ( struct value_data * )

DEBUG_FUNCTION void debug_value_data ( )

   Dump the value chain data to stderr.

References value_data::e, internal_error(), value_data_entry::mode, value_data_entry::next_regno, and value_data_entry::oldest_regno.

static rtx find_oldest_value_reg	(	enum	reg_class,
		rtx	,
		struct value_data *
	)

static

static rtx find_oldest_value_reg ( )

static

   Find the oldest copy of the value contained in REGNO that is in
   register class CL and has mode MODE.  If found, return an rtx
   of that oldest register, otherwise return NULL.

     If we are accessing REG in some mode other that what we set it in,
     make sure that the replacement is valid.  In particular, consider
        (set (reg:DI r11) (...))
        (set (reg:SI r9) (reg:SI r11))
        (set (reg:SI r10) (...))
        (set (...) (reg:DI r9))
     Replacing r9 with r11 is invalid.

static void free_debug_insn_changes ( )

static

   Free all queued updates for DEBUG_INSNs that change some reg to
   register REGNO.

static bool gate_handle_cprop ( )

static

Referenced by validate_value_data().

static void init_value_data ( struct value_data * )

static

static void init_value_data ( )

static

   Initialize VD such that there are no known relationships between regs.

static int kill_autoinc_value	(	rtx *	,
		void *
	)

static

static int kill_autoinc_value ( )

static

   Called through for_each_rtx.  Kill any register used as the base of an
   auto-increment expression, and install that register as the root of its
   own value list.

static void kill_clobbered_value	(	rtx	,
		const_rtx	,
		void *
	)

static

static void kill_clobbered_value ( )

static

   Called through note_stores.  If X is clobbered, kill its value.

References kill_set_value_data::ignore_set_reg, and rtx_equal_p().

static void kill_set_value	(	rtx	,
		const_rtx	,
		void *
	)

static

static void kill_set_value ( )

static

   Called through note_stores.  If X is set, not clobbered, kill its
   current value and install it as the root of its own value list.

References kill_value(), RTX_AUTOINC, and set_value_regno().

static void kill_value	(	rtx	,
		struct value_data *
	)

static

Referenced by kill_set_value().

static void kill_value ( )

static

   Kill X.  This is a convenience function wrapping kill_value_regno
   so that we mind the mode the register is in.

static void kill_value_one_regno	(	unsigned	,
		struct value_data *
	)

static

Referenced by kill_value_regno().

static void kill_value_one_regno ( )

static

   Kill register REGNO.  This involves removing it from any value
   lists, and resetting the value mode to VOIDmode.  This is only a
   helper function; it does not handle any hard registers overlapping
   with REGNO.

static void kill_value_regno	(	unsigned	,
		unsigned	,
		struct value_data *
	)

static

static void kill_value_regno	(	unsigned int	regno,
		unsigned int	nregs,
		struct value_data *	vd
	)

static

   Kill the value in register REGNO for NREGS, and any other registers
   whose values overlap.

     Kill the value we're told to kill.

     Kill everything that overlapped what we're told to kill.

References value_data::e, kill_value_one_regno(), and value_data_entry::mode.

rtl_opt_pass* make_pass_cprop_hardreg ( )

static rtx maybe_mode_change	(	enum machine_mode	orig_mode,
		enum machine_mode	copy_mode,
		enum machine_mode	new_mode,
		unsigned int	regno,
		unsigned int	copy_regno
	)

static

   Register REGNO was originally set in ORIG_MODE.  It - or a copy of it -
   was copied in COPY_MODE to COPY_REGNO, and then COPY_REGNO was accessed
   in NEW_MODE.
   Return a NEW_MODE rtx for REGNO if that's OK, otherwise return NULL_RTX.

static bool mode_change_ok	(	enum machine_mode	orig_mode,
		enum machine_mode	new_mode,
		unsigned int	regno
	)

static

   Return true if a mode change from ORIG to NEW is allowed for REGNO.

static bool replace_oldest_value_addr	(	rtx *	loc,
		enum reg_class	cl,
		enum machine_mode	mode,
		addr_space_t	as,
		rtx	insn,
		struct value_data *	vd
	)

static

   Similar to replace_oldest_value_reg, but *LOC contains an address.
   Adapted from find_reloads_address_1.  CL is INDEX_REG_CLASS or
   BASE_REG_CLASS depending on how the register is being considered.

static bool replace_oldest_value_mem	(	rtx	,
		rtx	,
		struct value_data *
	)

static

static bool replace_oldest_value_mem ( )

static

   Similar to replace_oldest_value_reg, but X contains a memory.

static bool replace_oldest_value_reg	(	rtx *	loc,
		enum reg_class	cl,
		rtx	insn,
		struct value_data *	vd
	)

static

   If possible, replace the register at *LOC with the oldest register
   in register class CL.  Return true if successfully replaced.

static void set_value_regno	(	unsigned	,
		enum	machine_mode,
		struct value_data *
	)

static

Referenced by kill_set_value().

static void set_value_regno	(	unsigned int	regno,
		enum machine_mode	mode,
		struct value_data *	vd
	)

static

   Remember that REGNO is valid in MODE.

References value_data_entry::debug_insn_changes, value_data::e, value_data::max_value_regs, value_data_entry::mode, value_data::n_debug_insn_changes, value_data_entry::next_regno, and value_data_entry::oldest_regno.

static void validate_value_data ( struct value_data * )

static

static void validate_value_data ( )

static

References copyprop_hardreg_forward(), execute(), and gate_handle_cprop().

Variable Documentation

alloc_pool debug_insn_changes_pool

static

Data Structures

Functions

Variables

Function Documentation

Variable Documentation