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* [Bug middle-end/42995] New: [4.3 regression] inline-small-functions does not inline simple delegation calls
@ 2010-02-07 23:01 matt at use dot net
2010-02-07 23:04 ` [Bug middle-end/42995] " pinskia at gcc dot gnu dot org
` (4 more replies)
0 siblings, 5 replies; 6+ messages in thread
From: matt at use dot net @ 2010-02-07 23:01 UTC (permalink / raw)
To: gcc-bugs
Using gcc 4.4.1 under Ubuntu 9.10 on amd64:
main.c:
#include "database.h"
int main()
{
int my_id = 0;
int result_for_my_id = get_data_for(my_id);
switch (result_for_my_id)
{
case 0:
return 666;
default:
return -1;
}
}
database.h:
#include <stdlib.h>
int get_data_for(int id)
{
return rand();
}
Compiling with:
gcc -O2 main.c -o n
produces this code:
0000000000400380 <main>:
400380: 48 83 ec 08 sub rsp,0x8
400384: 31 ff xor edi,edi
400386: e8 e5 ff ff ff call 400370 <get_data_for>
40038b: 83 f8 01 cmp eax,0x1
40038e: 19 c0 sbb eax,eax
400390: 48 83 c4 08 add rsp,0x8
400394: 25 9b 02 00 00 and eax,0x29b
400399: 83 e8 01 sub eax,0x1
40039c: c3 ret
40039d: 0f 1f 00 nop DWORD PTR [rax]
Note the 3 bytes of padding after the return. I'm confused why
inline-small-functions does not inline get_data_for. I tried this experiment:
gcc -O2 -finline-functions --param max-inline-insns-auto=20 main.c -o n
which produces this code:
0000000000400380 <main>:
400380: 48 83 ec 08 sub rsp,0x8
400384: e8 27 02 00 00 call 4005b0 <rand@plt>
400389: 83 f8 01 cmp eax,0x1
40038c: 19 c0 sbb eax,eax
40038e: 48 83 c4 08 add rsp,0x8
400392: 25 9b 02 00 00 and eax,0x29b
400397: 83 e8 01 sub eax,0x1
40039a: c3 ret
40039b: 0f 1f 44 00 00 nop DWORD PTR [rax+rax*1+0x0]
The padding got larger, but the code is actually smaller. Shouldn't the
heuristic used for inline-small-functions have caused get_data_for() to be
inlined?
This does not appear to be a problem in GCC 4.5.20091228 or 4.3.4.
--
Summary: [4.3 regression] inline-small-functions does not inline
simple delegation calls
Product: gcc
Version: 4.4.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: middle-end
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: matt at use dot net
GCC build triplet: x86_64-linux-unknown
GCC host triplet: x86_64-linux-unknown
GCC target triplet: x86_64-linux-unknown
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42995
^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug middle-end/42995] [4.3 regression] inline-small-functions does not inline simple delegation calls
2010-02-07 23:01 [Bug middle-end/42995] New: [4.3 regression] inline-small-functions does not inline simple delegation calls matt at use dot net
@ 2010-02-07 23:04 ` pinskia at gcc dot gnu dot org
2010-02-08 10:19 ` [Bug middle-end/42995] [4.4 Regression] " rguenth at gcc dot gnu dot org
` (3 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2010-02-07 23:04 UTC (permalink / raw)
To: gcc-bugs
------- Comment #1 from pinskia at gcc dot gnu dot org 2010-02-07 23:03 -------
>The padding got larger,
But the alignment stayed the same. :).
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42995
^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug middle-end/42995] [4.4 Regression] inline-small-functions does not inline simple delegation calls
2010-02-07 23:01 [Bug middle-end/42995] New: [4.3 regression] inline-small-functions does not inline simple delegation calls matt at use dot net
2010-02-07 23:04 ` [Bug middle-end/42995] " pinskia at gcc dot gnu dot org
@ 2010-02-08 10:19 ` rguenth at gcc dot gnu dot org
2010-02-08 10:41 ` rguenth at gcc dot gnu dot org
` (2 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: rguenth at gcc dot gnu dot org @ 2010-02-08 10:19 UTC (permalink / raw)
To: gcc-bugs
------- Comment #2 from rguenth at gcc dot gnu dot org 2010-02-08 10:19 -------
It doesn't inline it because:
Considering inline candidate get_data_for.
Not inlining: code size would grow by 3 insns.
The callee is estimated to have size 16 while the call costs less. The issue
is a missing check for VOID_TYPE_P in estimate_num_insns which has been
fixed for 4.5.
I have a fix.
--
rguenth at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
AssignedTo|unassigned at gcc dot gnu |rguenth at gcc dot gnu dot
|dot org |org
Status|UNCONFIRMED |ASSIGNED
Ever Confirmed|0 |1
Known to fail| |4.4.3
Known to work| |4.3.4 4.5.0
Last reconfirmed|0000-00-00 00:00:00 |2010-02-08 10:19:12
date| |
Summary|[4.3 regression] inline- |[4.4 Regression] inline-
|small-functions does not |small-functions does not
|inline simple delegation |inline simple delegation
|calls |calls
Target Milestone|--- |4.4.4
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42995
^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug middle-end/42995] [4.4 Regression] inline-small-functions does not inline simple delegation calls
2010-02-07 23:01 [Bug middle-end/42995] New: [4.3 regression] inline-small-functions does not inline simple delegation calls matt at use dot net
2010-02-07 23:04 ` [Bug middle-end/42995] " pinskia at gcc dot gnu dot org
2010-02-08 10:19 ` [Bug middle-end/42995] [4.4 Regression] " rguenth at gcc dot gnu dot org
@ 2010-02-08 10:41 ` rguenth at gcc dot gnu dot org
2010-02-08 14:11 ` rguenth at gcc dot gnu dot org
2010-02-08 14:11 ` rguenth at gcc dot gnu dot org
4 siblings, 0 replies; 6+ messages in thread
From: rguenth at gcc dot gnu dot org @ 2010-02-08 10:41 UTC (permalink / raw)
To: gcc-bugs
------- Comment #3 from rguenth at gcc dot gnu dot org 2010-02-08 10:41 -------
Subject: Bug 42995
Author: rguenth
Date: Mon Feb 8 10:41:25 2010
New Revision: 156598
URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=156598
Log:
2010-02-08 Richard Guenther <rguenther@suse.de>
PR middle-end/42995
* gcc.dg/tree-ssa/inline-4.c: New testcase.
Added:
trunk/gcc/testsuite/gcc.dg/tree-ssa/inline-4.c
Modified:
trunk/gcc/testsuite/ChangeLog
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42995
^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug middle-end/42995] [4.4 Regression] inline-small-functions does not inline simple delegation calls
2010-02-07 23:01 [Bug middle-end/42995] New: [4.3 regression] inline-small-functions does not inline simple delegation calls matt at use dot net
` (2 preceding siblings ...)
2010-02-08 10:41 ` rguenth at gcc dot gnu dot org
@ 2010-02-08 14:11 ` rguenth at gcc dot gnu dot org
2010-02-08 14:11 ` rguenth at gcc dot gnu dot org
4 siblings, 0 replies; 6+ messages in thread
From: rguenth at gcc dot gnu dot org @ 2010-02-08 14:11 UTC (permalink / raw)
To: gcc-bugs
------- Comment #5 from rguenth at gcc dot gnu dot org 2010-02-08 14:11 -------
Fixed.
--
rguenth at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|ASSIGNED |RESOLVED
Resolution| |FIXED
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42995
^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug middle-end/42995] [4.4 Regression] inline-small-functions does not inline simple delegation calls
2010-02-07 23:01 [Bug middle-end/42995] New: [4.3 regression] inline-small-functions does not inline simple delegation calls matt at use dot net
` (3 preceding siblings ...)
2010-02-08 14:11 ` rguenth at gcc dot gnu dot org
@ 2010-02-08 14:11 ` rguenth at gcc dot gnu dot org
4 siblings, 0 replies; 6+ messages in thread
From: rguenth at gcc dot gnu dot org @ 2010-02-08 14:11 UTC (permalink / raw)
To: gcc-bugs
------- Comment #4 from rguenth at gcc dot gnu dot org 2010-02-08 14:10 -------
Subject: Bug 42995
Author: rguenth
Date: Mon Feb 8 14:10:15 2010
New Revision: 156601
URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=156601
Log:
2010-02-08 Richard Guenther <rguenther@suse.de>
PR middle-end/42995
* tree-inline.c (estimate_move_cost): Assert we are not called
with a void type.
(estimate_num_insns): Do not count the terminating void_type_node
of a function argument type list.
Backport from mainline:
2010-01-06 Richard Guenther <rguenther@suse.de>
* ipa-inline.c (cgraph_decide_inlining_incrementally): Do
not inline regular functions into always-inline functions.
2010-01-05 Martin Jambor <mjambor@suse.cz>
PR tree-optimization/42462
* ipa-inline.c (compute_inline_parameters): Pass node->decl instead of
current_function_decl to helper functions and macros.
* gcc.dg/tree-ssa/inline-4.c: New testcase.
* gcc.dg/Wunreachable-2.c: Remove.
Added:
branches/gcc-4_4-branch/gcc/testsuite/gcc.dg/tree-ssa/inline-4.c
Removed:
branches/gcc-4_4-branch/gcc/testsuite/gcc.dg/Wunreachable-2.c
Modified:
branches/gcc-4_4-branch/gcc/ChangeLog
branches/gcc-4_4-branch/gcc/ipa-inline.c
branches/gcc-4_4-branch/gcc/tree-inline.c
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42995
^ permalink raw reply [flat|nested] 6+ messages in thread
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2010-02-07 23:01 [Bug middle-end/42995] New: [4.3 regression] inline-small-functions does not inline simple delegation calls matt at use dot net
2010-02-07 23:04 ` [Bug middle-end/42995] " pinskia at gcc dot gnu dot org
2010-02-08 10:19 ` [Bug middle-end/42995] [4.4 Regression] " rguenth at gcc dot gnu dot org
2010-02-08 10:41 ` rguenth at gcc dot gnu dot org
2010-02-08 14:11 ` rguenth at gcc dot gnu dot org
2010-02-08 14:11 ` rguenth at gcc dot gnu dot org
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