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riscv-gcc-1
Commit 7142e318 by John Wehle Committed by John Wehle
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rtl.h (set_noop_p): Declare. 

	* rtl.h (set_noop_p): Declare.
	* flow.c (set_noop_p): Move from here ...
	* rtlanal.c (set_noop_p): ... to here and enhance.
	* cse.c (delete_trivially_dead_insns): Use it.
	* gcse.c (hash_scan_set): Likewise.
	* jump.c (delete_noop_moves): Likewise.
	* recog.c (split_all_insns): Likewise.

From-SVN: r41077
parent 0c918ce5
Showing with 52 additions and 54 deletions
gcc/ChangeLog
Wed Apr 4 00:45:38 EDT 2001 John Wehle (john@feith.com)
* rtl.h (set_noop_p): Declare.
* flow.c (set_noop_p): Move from here ...
* rtlanal.c (set_noop_p): ... to here and enhance.
* cse.c (delete_trivially_dead_insns): Use it.
* gcse.c (hash_scan_set): Likewise.
* jump.c (delete_noop_moves): Likewise.
* recog.c (split_all_insns): Likewise.
2001-04-04 Alan Modra <alan@linuxcare.com.au>
* dwarf2out.c (dwarf2out_frame_debug_expr): Support adjusting
......
gcc/cse.c
......@@ -7612,14 +7612,7 @@ delete_trivially_dead_insns (insns, nreg)
live_insn = ! dead_libcall;
else if (GET_CODE (PATTERN (insn)) == SET)
{
if ((GET_CODE (SET_DEST (PATTERN (insn))) == REG
|| GET_CODE (SET_DEST (PATTERN (insn))) == SUBREG)
&& rtx_equal_p (SET_DEST (PATTERN (insn)),
SET_SRC (PATTERN (insn))))
;
else if (GET_CODE (SET_DEST (PATTERN (insn))) == STRICT_LOW_PART
&& rtx_equal_p (XEXP (SET_DEST (PATTERN (insn)), 0),
SET_SRC (PATTERN (insn))))
if (set_noop_p (PATTERN (insn)))
;
#ifdef HAVE_cc0
......@@ -7649,9 +7642,7 @@ delete_trivially_dead_insns (insns, nreg)
if (GET_CODE (elt) == SET)
{
if ((GET_CODE (SET_DEST (elt)) == REG
|| GET_CODE (SET_DEST (elt)) == SUBREG)
&& rtx_equal_p (SET_DEST (elt), SET_SRC (elt)))
if (set_noop_p (elt))
;
#ifdef HAVE_cc0
......
gcc/flow.c
......@@ -386,7 +386,6 @@ static void tidy_fallthru_edges PARAMS ((void));
static int verify_wide_reg_1 PARAMS ((rtx *, void *));
static void verify_wide_reg PARAMS ((int, rtx, rtx));
static void verify_local_live_at_start PARAMS ((regset, basic_block));
static int set_noop_p PARAMS ((rtx));
static int noop_move_p PARAMS ((rtx));
static void delete_noop_moves PARAMS ((rtx));
static void notice_stack_pointer_modification_1 PARAMS ((rtx, rtx, void *));
......@@ -3077,27 +3076,6 @@ free_basic_block_vars (keep_head_end_p)
}
}
/* Return nonzero if the destination of SET equals the source. */
static int
set_noop_p (set)
rtx set;
{
rtx src = SET_SRC (set);
rtx dst = SET_DEST (set);
if (GET_CODE (src) == SUBREG && GET_CODE (dst) == SUBREG)
{
if (SUBREG_BYTE (src) != SUBREG_BYTE (dst))
return 0;
src = SUBREG_REG (src);
dst = SUBREG_REG (dst);
}
return (GET_CODE (src) == REG && GET_CODE (dst) == REG
&& REGNO (src) == REGNO (dst));
}
/* Return nonzero if an insn consists only of SETs, each of which only sets a
value to itself. */
......
gcc/gcse.c
......@@ -1964,7 +1964,7 @@ hash_scan_set (pat, insn, set_p)
/* Is SET_SRC something we want to gcse? */
&& want_to_gcse_p (src)
/* Don't CSE a nop. */
&& src != dest)
&& ! set_noop_p (pat))
{
/* An expression is not anticipatable if its operands are
modified before this insn or if this is not the only SET in
......
gcc/jump.c
......@@ -956,15 +956,7 @@ delete_noop_moves (f)
/* Detect and delete no-op move instructions
resulting from not allocating a parameter in a register. */
if (GET_CODE (body) == SET
&& (SET_DEST (body) == SET_SRC (body)
|| (GET_CODE (SET_DEST (body)) == MEM
&& GET_CODE (SET_SRC (body)) == MEM
&& rtx_equal_p (SET_SRC (body), SET_DEST (body))))
&& ! (GET_CODE (SET_DEST (body)) == MEM
&& MEM_VOLATILE_P (SET_DEST (body)))
&& ! (GET_CODE (SET_SRC (body)) == MEM
&& MEM_VOLATILE_P (SET_SRC (body))))
if (GET_CODE (body) == SET && set_noop_p (body))
delete_computation (insn);
/* Detect and ignore no-op move instructions
......@@ -1073,16 +1065,6 @@ delete_noop_moves (f)
if (i < 0)
delete_insn (insn);
}
/* Also delete insns to store bit fields if they are no-ops. */
/* Not worth the hair to detect this in the big-endian case. */
else if (! BYTES_BIG_ENDIAN
&& GET_CODE (body) == SET
&& GET_CODE (SET_DEST (body)) == ZERO_EXTRACT
&& XEXP (SET_DEST (body), 2) == const0_rtx
&& XEXP (SET_DEST (body), 0) == SET_SRC (body)
&& ! (GET_CODE (SET_SRC (body)) == MEM
&& MEM_VOLATILE_P (SET_SRC (body))))
delete_insn (insn);
}
insn = next;
}
......
gcc/recog.c
......@@ -2882,7 +2882,7 @@ split_all_insns (upd_life)
break the code that handles REG_NO_CONFLICT blocks. */
else if ((set = single_set (insn)) != NULL
&& rtx_equal_p (SET_SRC (set), SET_DEST (set)))
&& set_noop_p (set))
{
/* Nops get in the way while scheduling, so delete them
now if register allocation has already been done. It
......
gcc/rtl.h
......@@ -1401,6 +1401,7 @@ extern int insn_dependent_p PARAMS ((rtx, rtx));
extern int reg_set_p PARAMS ((rtx, rtx));
extern rtx single_set_2 PARAMS ((rtx, rtx));
extern int multiple_sets PARAMS ((rtx));
extern int set_noop_p PARAMS ((rtx));
extern rtx find_last_value PARAMS ((rtx, rtx *, rtx, int));
extern int refers_to_regno_p PARAMS ((unsigned int, unsigned int,
rtx, rtx *));
......
gcc/rtlanal.c
......@@ -980,6 +980,42 @@ multiple_sets (insn)
return 0;
}
/* Return nonzero if the destination of SET equals the source
and there are no side effects. */
int
set_noop_p (set)
rtx set;
{
rtx src = SET_SRC (set);
rtx dst = SET_DEST (set);
if (side_effects_p (src) || side_effects_p (dst))
return 0;
if (GET_CODE (dst) == MEM && GET_CODE (src) == MEM)
return rtx_equal_p (dst, src);
if (GET_CODE (dst) == SIGN_EXTRACT
|| GET_CODE (dst) == ZERO_EXTRACT)
return rtx_equal_p (XEXP (dst, 0), src)
&& ! BYTES_BIG_ENDIAN && XEXP (dst, 2) == const0_rtx;
if (GET_CODE (dst) == STRICT_LOW_PART)
dst = XEXP (dst, 0);
if (GET_CODE (src) == SUBREG && GET_CODE (dst) == SUBREG)
{
if (SUBREG_BYTE (src) != SUBREG_BYTE (dst))
return 0;
src = SUBREG_REG (src);
dst = SUBREG_REG (dst);
}
return (GET_CODE (src) == REG && GET_CODE (dst) == REG
&& REGNO (src) == REGNO (dst));
}
/* Return the last thing that X was assigned from before *PINSN. If VALID_TO
is not NULL_RTX then verify that the object is not modified up to VALID_TO.
If the object was modified, if we hit a partial assignment to X, or hit a
......
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