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Commit 0acba2b4 by Eric Botcazou Committed by Eric Botcazou
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implicit-zee.c (combine_reaching_defs): Fix long lines. 

	* implicit-zee.c (combine_reaching_defs): Fix long lines.
	(is_set_with_extension_DI): Delete.
	(struct zero_extend_info): New structure.
	(add_removable_zero_extend ): New function.
	(find_removable_zero_extends): Use note_stores to find SETs.
	(find_and_remove_ze): Fix long line, remove superfluous parentheses.

From-SVN: r161736
parent 7a0208b7
Showing with 88 additions and 86 deletions
gcc/ChangeLog
2010-07-02 Eric Botcazou <ebotcazou@adacore.com>
* implicit-zee.c (combine_reaching_defs): Fix long lines.
(is_set_with_extension_DI): Delete.
(struct zero_extend_info): New structure.
(add_removable_zero_extend ): New function.
(find_removable_zero_extends): Use note_stores to find SETs.
(find_and_remove_ze): Fix long line, remove superfluous parentheses.
2010-07-02 Changpeng Fang <changpeng.fang@amd.com>
* tree-ssa-loop-prefetch.c (compute_miss_rate): Rename to
......
gcc/implicit-zee.c
......@@ -100,17 +100,17 @@ along with GCC; see the file COPYING3. If not see
}
**********************************************
$ gcc -O2 -fsee bad_code.c (Turned on existing sign-extension elimination.)
$ gcc -O2 -fsee bad_code.c (Turned on existing sign-extension elimination)
........
400315: b8 4e 00 00 00 mov $0x4e,%eax
40031a: 0f af f8 imul %eax,%edi
40031d: 89 ff mov %edi,%edi ---> Useless extend.
40031d: 89 ff mov %edi,%edi --> Useless extend
40031f: 8b 04 bd 60 19 40 00 mov 0x401960(,%rdi,4),%eax
400326: c3 retq
......
400330: ba 2d 00 00 00 mov $0x2d,%edx
400335: 0f af fa imul %edx,%edi
400338: 89 ff mov %edi,%edi ---> Useless extend.
400338: 89 ff mov %edi,%edi --> Useless extend
40033a: 8b 04 bd 60 19 40 00 mov 0x401960(,%rdi,4),%eax
400341: c3 retq
......@@ -141,14 +141,14 @@ along with GCC; see the file COPYING3. If not see
return (unsigned long long)(z);
}
$ gcc -O2 -fsee bad_code.c (Turned on existing sign-extension elimination.)
$ gcc -O2 -fsee bad_code.c (Turned on existing sign-extension elimination)
............
400360: 8d 14 3e lea (%rsi,%rdi,1),%edx
400363: 89 f8 mov %edi,%eax
400365: 29 f0 sub %esi,%eax
400367: 83 ff 65 cmp $0x65,%edi
40036a: 0f 43 c2 cmovae %edx,%eax
40036d: 89 c0 mov %eax,%eax ---> Useless extend.
40036d: 89 c0 mov %eax,%eax --> Useless extend
40036f: c3 retq
$ gcc -O2 -fzee bad_code.c
......@@ -165,16 +165,13 @@ along with GCC; see the file COPYING3. If not see
Usefulness :
----------
This pass reduces the dynamic instruction count of a compression benchmark by
2.8% and improves its run-time by about 1%. The compression benchmark had the
following code sequence in a very hot region of code before ZEE optimized it :
This pass reduces the dynamic instruction count of a compression benchmark
by 2.8% and improves its run time by about 1%. The compression benchmark
had the following code sequence in a very hot region of code before ZEE
optimized it :
shr $0x5, %edx
mov %edx, %edx --> Useless zero-extend.
How to turn on ?
----------------
-fzee -O2. */
mov %edx, %edx --> Useless zero-extend */
#include "config.h"
......@@ -240,31 +237,6 @@ set_insn_status (rtx insn, enum insn_merge_code code)
is_insn_merge_attempted[INSN_UID (insn)] = code;
}
/* Check to see if this zero-extend matches a pattern
that could be eliminated. This is called via
for_each_rtx in function find_and_remove_ze. */
static int
is_set_with_extension_DI (rtx *expr, void *data)
{
/* Looking only for patterns of the type :
SET (REG:DI X) (ZERO_EXTEND (REG:SI x))
*/
if (GET_CODE (*expr) == SET
&& GET_MODE (SET_DEST (*expr)) == DImode
&& GET_CODE (SET_DEST (*expr)) == REG
&& GET_CODE (SET_SRC (*expr)) == ZERO_EXTEND
&& GET_CODE (XEXP (SET_SRC (*expr),0)) == REG
&& GET_MODE (XEXP (SET_SRC (*expr),0)) == SImode
&& REGNO (SET_DEST (*expr)) == REGNO (XEXP (SET_SRC (*expr),0)))
{
*(rtx **)(data) = expr;
return 1;
}
return 0;
}
/* Given a insn (CURR_INSN) and a pointer to the SET rtx (ORIG_SET)
that needs to be modified, this code modifies the SET rtx to a
new SET rtx that zero_extends the right hand expression into a DImode
......@@ -737,7 +709,7 @@ combine_reaching_defs (rtx zero_extend_insn, rtx set_pat)
VEC_free (rtx, heap, defs_list);
VEC_free (rtx, heap, copies_list);
if (dump_file)
fprintf (dump_file, "All definitions have been merged previously...\n");
fprintf (dump_file, "All definitions have been merged previously.\n");
return true;
}
......@@ -812,8 +784,8 @@ combine_reaching_defs (rtx zero_extend_insn, rtx set_pat)
}
else
{
/* Changes need not be cancelled explicitly as apply_change_group ()
does it. Print list of definitions in the dump_file for debug
/* Changes need not be cancelled explicitly as apply_change_group
does it. Print list of definitions in the dump_file for debug
purposes. This zero-extension cannot be deleted. */
if (dump_file)
......@@ -838,50 +810,74 @@ combine_reaching_defs (rtx zero_extend_insn, rtx set_pat)
return false;
}
/* Goes through the instruction stream looking for zero-extends. If the zero
extension instruction has atleast one def it adds it to a list of possible
candidates for deletion. It returns the list of candidates. */
/* Carry information about zero-extensions while walking the RTL. */
struct zero_extend_info
{
/* The insn where the zero-extension is. */
rtx insn;
/* The list of candidates. */
VEC (rtx, heap) *insn_list;
};
/* Add a zero-extend pattern that could be eliminated. This is called via
note_stores from find_removable_zero_extends. */
static void
add_removable_zero_extend (rtx x ATTRIBUTE_UNUSED, const_rtx expr, void *data)
{
struct zero_extend_info *zei = (struct zero_extend_info *)data;
rtx src, dest;
/* We are looking for SET (REG:DI N) (ZERO_EXTEND (REG:SI N)). */
if (GET_CODE (expr) != SET)
return;
src = SET_SRC (expr);
dest = SET_DEST (expr);
if (REG_P (dest)
&& GET_MODE (dest) == DImode
&& GET_CODE (src) == ZERO_EXTEND
&& REG_P (XEXP (src, 0))
&& GET_MODE (XEXP (src, 0)) == SImode
&& REGNO (dest) == REGNO (XEXP (src, 0)))
{
if (get_defs (zei->insn, XEXP (src, 0), NULL))
VEC_safe_push (rtx, heap, zei->insn_list, zei->insn);
else if (dump_file)
{
fprintf (dump_file, "Cannot eliminate zero-extension: \n");
print_rtl_single (dump_file, zei->insn);
fprintf (dump_file, "No defs. Could be extending parameters.\n");
}
}
}
/* Traverse the instruction stream looking for zero-extends and return the
list of candidates. */
static VEC (rtx,heap)*
find_removable_zero_extends (void)
{
VEC (rtx, heap) *zeinsn_list;
basic_block curr_block;
rtx curr_insn;
rtx *set_insn;
rtx which_reg;
int type ;
int has_defs;
zeinsn_list = VEC_alloc (rtx, heap, 8);
FOR_EACH_BB (curr_block)
{
FOR_BB_INSNS (curr_block, curr_insn)
{
if (!NONDEBUG_INSN_P (curr_insn))
continue;
struct zero_extend_info zei;
basic_block bb;
rtx insn;
type = for_each_rtx (&PATTERN (curr_insn),
is_set_with_extension_DI,
(void *)&set_insn);
zei.insn_list = VEC_alloc (rtx, heap, 8);
if (!type)
continue;
FOR_EACH_BB (bb)
FOR_BB_INSNS (bb, insn)
{
if (!NONDEBUG_INSN_P (insn))
continue;
which_reg = XEXP (SET_SRC (*set_insn), 0);
has_defs = get_defs (curr_insn, which_reg, NULL);
if (has_defs)
VEC_safe_push (rtx, heap, zeinsn_list, curr_insn);
else if (dump_file)
{
fprintf (dump_file, "Cannot eliminate zero extension : \n");
print_rtl_single (dump_file, curr_insn);
fprintf (dump_file,
"This has no defs. Could be extending parameters.\n");
}
}
}
return zeinsn_list;
zei.insn = insn;
note_stores (PATTERN (insn), add_removable_zero_extend, &zei);
}
return zei.insn_list;
}
/* This is the main function that checks the insn stream for redundant
......@@ -906,13 +902,12 @@ find_and_remove_ze (void)
max_insn_uid = get_max_uid ();
is_insn_merge_attempted = XNEWVEC (enum insn_merge_code,
sizeof (enum insn_merge_code)* max_insn_uid);
is_insn_merge_attempted
= XNEWVEC (enum insn_merge_code,
sizeof (enum insn_merge_code) * max_insn_uid);
for (i = 0; i < max_insn_uid; i++)
{
is_insn_merge_attempted[i] = MERGE_NOT_ATTEMPTED;
}
is_insn_merge_attempted[i] = MERGE_NOT_ATTEMPTED;
num_ze_opportunities = num_realized = 0;
......@@ -942,9 +937,7 @@ find_and_remove_ze (void)
/* Delete all useless zero extensions here in one sweep. */
for (ix = 0; VEC_iterate (rtx, zeinsn_del_list, ix, curr_insn); ix++)
{
delete_insn (curr_insn);
}
delete_insn (curr_insn);
free (is_insn_merge_attempted);
VEC_free (rtx, heap, zeinsn_list);
......
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