public inbox for gcc-cvs@sourceware.org
help / color / mirror / Atom feed
From: Michael Meissner <meissner@gcc.gnu.org>
To: gcc-cvs@gcc.gnu.org
Subject: [gcc(refs/users/meissner/heads/work119-dmf)] Make load/cmp fusion know about prefixed loads.
Date: Mon, 17 Apr 2023 19:43:46 +0000 (GMT) [thread overview]
Message-ID: <20230417194346.F1232385734B@sourceware.org> (raw)
https://gcc.gnu.org/g:a8a8d23787228a9712b49b21296cc63e214f0d6b
commit a8a8d23787228a9712b49b21296cc63e214f0d6b
Author: Michael Meissner <meissner@linux.ibm.com>
Date: Mon Apr 17 15:43:28 2023 -0400
Make load/cmp fusion know about prefixed loads.
I posted a version of patch on March 21st and a second version on March 24th.
This patch makes some code changes suggested in the genfusion.pl code from the
last 2 patch submissions. The fusion.md that is produced by genfusion.pl is
the same in all 3 versions.
I changed the genfusion.pl to match the suggestion for code layout. I also
used the correct comment for each of the instructions (in the 2nd patch, the
when I rewrote the comments about ld and lwa being DS format instructions, I
had put the ld comment in the section handling lwa, and vice versa).
I also removed lp64 from the new test. When I first added the prefixed code,
it was only done for 64-bit, but now it is allowed for 32-bit. However, the
case that shows up (lwa) would not hit in 32-bit, since it only generates lwz
and not lwa. It also would not generate ld. But the test does pass when it is
built with -m32.
The issue with the bug is the power10 load GPR + cmpi -1/0/1 fusion
optimization generates illegal assembler code.
Ultimately the code was dying because the fusion load + compare -1/0/1 patterns
did not handle the possibility that the load might be prefixed.
The main cause is the constraints for the individual loads in the fusion did not
match the machine. In particular, LWA is a ds format instruction when it is
unprefixed. The code did not also set the prefixed attribute correctly.
This patch rewrites the genfusion.pl script so that it will have more accurate
constraints for the LWA and LD instructions (which are DS instructions). The
updated genfusion.pl was then run to update fusion.md. Finally, the code for
the "prefixed" attribute is modified so that it considers load + compare
immediate patterns to be like the normal load insns in checking whether
operand[1] is a prefixed instruction.
I have tested this code on a power9 little endian system (with long double
being IEEE 128-bit and IBM 128-bit), a power10 little endian system, and a
power8 big endian system, testing both 32-bit and 64-bit code generation. Can
I put this code into the master branch, and after a waiting period, apply it to
the GCC 12 and GCC 11 branches (the bug does show up in those branches, and the
patch applies without change).
2023-04-17 Michael Meissner <meissner@linux.ibm.com>
gcc/
PR target/105325
* gcc/config/rs6000/genfusion.pl (gen_ld_cmpi_p10): Improve generation
of the ld and lwa instructions which use the DS encoding instead of D.
Use the YZ constraint for these loads. Handle prefixed loads better.
Set the sign_extend attribute as appropriate.
* gcc/config/rs6000/fusion.md: Regenerate.
* gcc/config/rs6000/rs6000.md (prefixed attribute): Add fused_load_cmpi
instructions to the list of instructions that might have a prefixed load
instruction.
gcc/testsuite/
PR target/105325
* g++.target/powerpc/pr105325.C: New test.
* gcc.target/powerpc/fusion-p10-ldcmpi.c: Adjust insn counts.
Diff:
---
gcc/config/rs6000/fusion.md | 17 ++++++++------
gcc/config/rs6000/genfusion.pl | 26 ++++++++++++++++++----
gcc/config/rs6000/rs6000.md | 2 +-
gcc/testsuite/g++.target/powerpc/pr105325.C | 24 ++++++++++++++++++++
.../gcc.target/powerpc/fusion-p10-ldcmpi.c | 4 ++--
5 files changed, 59 insertions(+), 14 deletions(-)
diff --git a/gcc/config/rs6000/fusion.md b/gcc/config/rs6000/fusion.md
index d45fb138a70..da9953d9ad9 100644
--- a/gcc/config/rs6000/fusion.md
+++ b/gcc/config/rs6000/fusion.md
@@ -22,7 +22,7 @@
;; load mode is DI result mode is clobber compare mode is CC extend is none
(define_insn_and_split "*ld_cmpdi_cr0_DI_clobber_CC_none"
[(set (match_operand:CC 2 "cc_reg_operand" "=x")
- (compare:CC (match_operand:DI 1 "ds_form_mem_operand" "m")
+ (compare:CC (match_operand:DI 1 "ds_form_mem_operand" "YZ")
(match_operand:DI 3 "const_m1_to_1_operand" "n")))
(clobber (match_scratch:DI 0 "=r"))]
"(TARGET_P10_FUSION)"
@@ -43,7 +43,7 @@
;; load mode is DI result mode is clobber compare mode is CCUNS extend is none
(define_insn_and_split "*ld_cmpldi_cr0_DI_clobber_CCUNS_none"
[(set (match_operand:CCUNS 2 "cc_reg_operand" "=x")
- (compare:CCUNS (match_operand:DI 1 "ds_form_mem_operand" "m")
+ (compare:CCUNS (match_operand:DI 1 "ds_form_mem_operand" "YZ")
(match_operand:DI 3 "const_0_to_1_operand" "n")))
(clobber (match_scratch:DI 0 "=r"))]
"(TARGET_P10_FUSION)"
@@ -64,7 +64,7 @@
;; load mode is DI result mode is DI compare mode is CC extend is none
(define_insn_and_split "*ld_cmpdi_cr0_DI_DI_CC_none"
[(set (match_operand:CC 2 "cc_reg_operand" "=x")
- (compare:CC (match_operand:DI 1 "ds_form_mem_operand" "m")
+ (compare:CC (match_operand:DI 1 "ds_form_mem_operand" "YZ")
(match_operand:DI 3 "const_m1_to_1_operand" "n")))
(set (match_operand:DI 0 "gpc_reg_operand" "=r") (match_dup 1))]
"(TARGET_P10_FUSION)"
@@ -85,7 +85,7 @@
;; load mode is DI result mode is DI compare mode is CCUNS extend is none
(define_insn_and_split "*ld_cmpldi_cr0_DI_DI_CCUNS_none"
[(set (match_operand:CCUNS 2 "cc_reg_operand" "=x")
- (compare:CCUNS (match_operand:DI 1 "ds_form_mem_operand" "m")
+ (compare:CCUNS (match_operand:DI 1 "ds_form_mem_operand" "YZ")
(match_operand:DI 3 "const_0_to_1_operand" "n")))
(set (match_operand:DI 0 "gpc_reg_operand" "=r") (match_dup 1))]
"(TARGET_P10_FUSION)"
@@ -106,7 +106,7 @@
;; load mode is SI result mode is clobber compare mode is CC extend is none
(define_insn_and_split "*lwa_cmpdi_cr0_SI_clobber_CC_none"
[(set (match_operand:CC 2 "cc_reg_operand" "=x")
- (compare:CC (match_operand:SI 1 "ds_form_mem_operand" "m")
+ (compare:CC (match_operand:SI 1 "lwa_operand" "YZ")
(match_operand:SI 3 "const_m1_to_1_operand" "n")))
(clobber (match_scratch:SI 0 "=r"))]
"(TARGET_P10_FUSION)"
@@ -148,7 +148,7 @@
;; load mode is SI result mode is SI compare mode is CC extend is none
(define_insn_and_split "*lwa_cmpdi_cr0_SI_SI_CC_none"
[(set (match_operand:CC 2 "cc_reg_operand" "=x")
- (compare:CC (match_operand:SI 1 "ds_form_mem_operand" "m")
+ (compare:CC (match_operand:SI 1 "lwa_operand" "YZ")
(match_operand:SI 3 "const_m1_to_1_operand" "n")))
(set (match_operand:SI 0 "gpc_reg_operand" "=r") (match_dup 1))]
"(TARGET_P10_FUSION)"
@@ -190,7 +190,7 @@
;; load mode is SI result mode is EXTSI compare mode is CC extend is sign
(define_insn_and_split "*lwa_cmpdi_cr0_SI_EXTSI_CC_sign"
[(set (match_operand:CC 2 "cc_reg_operand" "=x")
- (compare:CC (match_operand:SI 1 "ds_form_mem_operand" "m")
+ (compare:CC (match_operand:SI 1 "lwa_operand" "YZ")
(match_operand:SI 3 "const_m1_to_1_operand" "n")))
(set (match_operand:EXTSI 0 "gpc_reg_operand" "=r") (sign_extend:EXTSI (match_dup 1)))]
"(TARGET_P10_FUSION)"
@@ -205,6 +205,7 @@
""
[(set_attr "type" "fused_load_cmpi")
(set_attr "cost" "8")
+ (set_attr "sign_extend" "yes")
(set_attr "length" "8")])
;; load-cmpi fusion pattern generated by gen_ld_cmpi_p10
@@ -247,6 +248,7 @@
""
[(set_attr "type" "fused_load_cmpi")
(set_attr "cost" "8")
+ (set_attr "sign_extend" "yes")
(set_attr "length" "8")])
;; load-cmpi fusion pattern generated by gen_ld_cmpi_p10
@@ -289,6 +291,7 @@
""
[(set_attr "type" "fused_load_cmpi")
(set_attr "cost" "8")
+ (set_attr "sign_extend" "yes")
(set_attr "length" "8")])
;; load-cmpi fusion pattern generated by gen_ld_cmpi_p10
diff --git a/gcc/config/rs6000/genfusion.pl b/gcc/config/rs6000/genfusion.pl
index e4db352e0ce..4f367cadc52 100755
--- a/gcc/config/rs6000/genfusion.pl
+++ b/gcc/config/rs6000/genfusion.pl
@@ -56,7 +56,7 @@ sub mode_to_ldst_char
sub gen_ld_cmpi_p10
{
my ($lmode, $ldst, $clobbermode, $result, $cmpl, $echr, $constpred,
- $mempred, $ccmode, $np, $extend, $resultmode);
+ $mempred, $ccmode, $np, $extend, $resultmode, $constraint);
LMODE: foreach $lmode ('DI','SI','HI','QI') {
$ldst = mode_to_ldst_char($lmode);
$clobbermode = $lmode;
@@ -71,21 +71,34 @@ sub gen_ld_cmpi_p10
CCMODE: foreach $ccmode ('CC','CCUNS') {
$np = "NON_PREFIXED_D";
$mempred = "non_update_memory_operand";
+ $constraint = "m";
if ( $ccmode eq 'CC' ) {
next CCMODE if $lmode eq 'QI';
- if ( $lmode eq 'DI' || $lmode eq 'SI' ) {
+ if ( $lmode eq 'HI' ) {
+ $np = "NON_PREFIXED_D";
+ $mempred = "non_update_memory_operand";
+ $echr = "a";
+ } elsif ( $lmode eq 'SI' ) {
+ # ld and lwa are both DS-FORM.
+ $np = "NON_PREFIXED_DS";
+ $mempred = "lwa_operand";
+ $echr = "a";
+ $constraint = "YZ";
+ } elsif ( $lmode eq 'DI' ) {
# ld and lwa are both DS-FORM.
$np = "NON_PREFIXED_DS";
$mempred = "ds_form_mem_operand";
+ $echr = "";
+ $constraint = "YZ";
}
$cmpl = "";
- $echr = "a";
$constpred = "const_m1_to_1_operand";
} else {
if ( $lmode eq 'DI' ) {
# ld is DS-form, but lwz is not.
$np = "NON_PREFIXED_DS";
$mempred = "ds_form_mem_operand";
+ $constraint = "YZ";
}
$cmpl = "l";
$echr = "z";
@@ -108,7 +121,7 @@ sub gen_ld_cmpi_p10
print "(define_insn_and_split \"*l${ldst}${echr}_cmp${cmpl}di_cr0_${lmode}_${result}_${ccmode}_${extend}\"\n";
print " [(set (match_operand:${ccmode} 2 \"cc_reg_operand\" \"=x\")\n";
- print " (compare:${ccmode} (match_operand:${lmode} 1 \"${mempred}\" \"m\")\n";
+ print " (compare:${ccmode} (match_operand:${lmode} 1 \"${mempred}\" \"${constraint}\")\n";
if ($ccmode eq 'CCUNS') { print " "; }
print " (match_operand:${lmode} 3 \"${constpred}\" \"n\")))\n";
if ($result eq 'clobber') {
@@ -137,6 +150,11 @@ sub gen_ld_cmpi_p10
print " \"\"\n";
print " [(set_attr \"type\" \"fused_load_cmpi\")\n";
print " (set_attr \"cost\" \"8\")\n";
+
+ if ($extend eq "sign") {
+ print " (set_attr \"sign_extend\" \"yes\")\n";
+ }
+
print " (set_attr \"length\" \"8\")])\n";
print "\n";
}
diff --git a/gcc/config/rs6000/rs6000.md b/gcc/config/rs6000/rs6000.md
index b0db8ae508d..0e1f4cb3868 100644
--- a/gcc/config/rs6000/rs6000.md
+++ b/gcc/config/rs6000/rs6000.md
@@ -302,7 +302,7 @@
(eq_attr "maybe_prefixed" "no"))
(const_string "no")
- (eq_attr "type" "load,fpload,vecload")
+ (eq_attr "type" "load,fpload,vecload,vecload,fused_load_cmpi")
(if_then_else (match_test "prefixed_load_p (insn)")
(const_string "yes")
(const_string "no"))
diff --git a/gcc/testsuite/g++.target/powerpc/pr105325.C b/gcc/testsuite/g++.target/powerpc/pr105325.C
new file mode 100644
index 00000000000..f4ab384daa7
--- /dev/null
+++ b/gcc/testsuite/g++.target/powerpc/pr105325.C
@@ -0,0 +1,24 @@
+/* { dg-do assemble } */
+/* { dg-require-effective-target lp64 } */
+/* { dg-require-effective-target powerpc_prefixed_addr } */
+/* { dg-options "-O2 -mdejagnu-cpu=power10 -fstack-protector" } */
+
+/* Test that power10 fusion does not generate an LWA/CMPDI instruction pair
+ instead of PLWZ/CMPWI. Ultimately the code was dying because the fusion
+ load + compare -1/0/1 patterns did not handle the possibility that the load
+ might be prefixed. */
+
+struct Ath__array1D {
+ int _current;
+ int getCnt() { return _current; }
+};
+struct extMeasure {
+ int _mapTable[10000];
+ Ath__array1D _metRCTable;
+};
+void measureRC() {
+ extMeasure m;
+ for (; m._metRCTable.getCnt();)
+ for (;;)
+ ;
+}
diff --git a/gcc/testsuite/gcc.target/powerpc/fusion-p10-ldcmpi.c b/gcc/testsuite/gcc.target/powerpc/fusion-p10-ldcmpi.c
index 526a026d874..ca7297375a4 100644
--- a/gcc/testsuite/gcc.target/powerpc/fusion-p10-ldcmpi.c
+++ b/gcc/testsuite/gcc.target/powerpc/fusion-p10-ldcmpi.c
@@ -61,7 +61,7 @@ TEST(int8_t)
/* { dg-final { scan-assembler-times "lha_cmpdi_cr0_HI_clobber_CC_sign" 16 { target lp64 } } } */
/* { dg-final { scan-assembler-times "lhz_cmpldi_cr0_HI_clobber_CCUNS_zero" 4 { target lp64 } } } */
/* { dg-final { scan-assembler-times "lwa_cmpdi_cr0_SI_EXTSI_CC_sign" 0 { target lp64 } } } */
-/* { dg-final { scan-assembler-times "lwa_cmpdi_cr0_SI_clobber_CC_none" 4 { target lp64 } } } */
+/* { dg-final { scan-assembler-times "lwa_cmpdi_cr0_SI_clobber_CC_none" 8 { target lp64 } } } */
/* { dg-final { scan-assembler-times "lwz_cmpldi_cr0_SI_EXTSI_CCUNS_zero" 0 { target lp64 } } } */
/* { dg-final { scan-assembler-times "lwz_cmpldi_cr0_SI_clobber_CCUNS_none" 2 { target lp64 } } } */
@@ -73,6 +73,6 @@ TEST(int8_t)
/* { dg-final { scan-assembler-times "lha_cmpdi_cr0_HI_clobber_CC_sign" 8 { target ilp32 } } } */
/* { dg-final { scan-assembler-times "lhz_cmpldi_cr0_HI_clobber_CCUNS_zero" 2 { target ilp32 } } } */
/* { dg-final { scan-assembler-times "lwa_cmpdi_cr0_SI_EXTSI_CC_sign" 0 { target ilp32 } } } */
-/* { dg-final { scan-assembler-times "lwa_cmpdi_cr0_SI_clobber_CC_none" 9 { target ilp32 } } } */
+/* { dg-final { scan-assembler-times "lwa_cmpdi_cr0_SI_clobber_CC_none" 16 { target ilp32 } } } */
/* { dg-final { scan-assembler-times "lwz_cmpldi_cr0_SI_EXTSI_CCUNS_zero" 0 { target ilp32 } } } */
/* { dg-final { scan-assembler-times "lwz_cmpldi_cr0_SI_clobber_CCUNS_none" 6 { target ilp32 } } } */
next reply other threads:[~2023-04-17 19:43 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-04-17 19:43 Michael Meissner [this message]
2023-04-26 5:15 Michael Meissner
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20230417194346.F1232385734B@sourceware.org \
--to=meissner@gcc.gnu.org \
--cc=gcc-cvs@gcc.gnu.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).