From: Aurelien Jarno <aurelien@aurel32.net>
To: qemu-devel@nongnu.org
Cc: Aurelien Jarno <aurelien@aurel32.net>
Subject: [Qemu-devel] [PATCH v2 07/10] tcg/optimize: further optimize brcond/movcond/setcond
Date: Fri, 21 Sep 2012 21:43:15 +0200 [thread overview]
Message-ID: <1348256598-8146-8-git-send-email-aurelien@aurel32.net> (raw)
In-Reply-To: <1348256598-8146-1-git-send-email-aurelien@aurel32.net>
When both argument of brcond/movcond/setcond are the same or when one
of the two values is a constant equal to zero, it's possible to do
further optimizations.
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
---
tcg/optimize.c | 127 +++++++++++++++++++++++++++++++++-----------------------
1 file changed, 76 insertions(+), 51 deletions(-)
diff --git a/tcg/optimize.c b/tcg/optimize.c
index ceea644..abe016a 100644
--- a/tcg/optimize.c
+++ b/tcg/optimize.c
@@ -292,58 +292,88 @@ static TCGArg do_constant_folding(TCGOpcode op, TCGArg x, TCGArg y)
return res;
}
+/* Return 2 if the condition can't be simplified, and the result
+ of the condition (0 or 1) if it can */
static TCGArg do_constant_folding_cond(TCGOpcode op, TCGArg x,
TCGArg y, TCGCond c)
{
- switch (op_bits(op)) {
- case 32:
+ if (temps[x].state == TCG_TEMP_CONST && temps[y].state == TCG_TEMP_CONST) {
+ switch (op_bits(op)) {
+ case 32:
+ switch (c) {
+ case TCG_COND_EQ:
+ return (uint32_t)temps[x].val == (uint32_t)temps[y].val;
+ case TCG_COND_NE:
+ return (uint32_t)temps[x].val != (uint32_t)temps[y].val;
+ case TCG_COND_LT:
+ return (int32_t)temps[x].val < (int32_t)temps[y].val;
+ case TCG_COND_GE:
+ return (int32_t)temps[x].val >= (int32_t)temps[y].val;
+ case TCG_COND_LE:
+ return (int32_t)temps[x].val <= (int32_t)temps[y].val;
+ case TCG_COND_GT:
+ return (int32_t)temps[x].val > (int32_t)temps[y].val;
+ case TCG_COND_LTU:
+ return (uint32_t)temps[x].val < (uint32_t)temps[y].val;
+ case TCG_COND_GEU:
+ return (uint32_t)temps[x].val >= (uint32_t)temps[y].val;
+ case TCG_COND_LEU:
+ return (uint32_t)temps[x].val <= (uint32_t)temps[y].val;
+ case TCG_COND_GTU:
+ return (uint32_t)temps[x].val > (uint32_t)temps[y].val;
+ }
+ break;
+ case 64:
+ switch (c) {
+ case TCG_COND_EQ:
+ return (uint64_t)temps[x].val == (uint64_t)temps[y].val;
+ case TCG_COND_NE:
+ return (uint64_t)temps[x].val != (uint64_t)temps[y].val;
+ case TCG_COND_LT:
+ return (int64_t)temps[x].val < (int64_t)temps[y].val;
+ case TCG_COND_GE:
+ return (int64_t)temps[x].val >= (int64_t)temps[y].val;
+ case TCG_COND_LE:
+ return (int64_t)temps[x].val <= (int64_t)temps[y].val;
+ case TCG_COND_GT:
+ return (int64_t)temps[x].val > (int64_t)temps[y].val;
+ case TCG_COND_LTU:
+ return (uint64_t)temps[x].val < (uint64_t)temps[y].val;
+ case TCG_COND_GEU:
+ return (uint64_t)temps[x].val >= (uint64_t)temps[y].val;
+ case TCG_COND_LEU:
+ return (uint64_t)temps[x].val <= (uint64_t)temps[y].val;
+ case TCG_COND_GTU:
+ return (uint64_t)temps[x].val > (uint64_t)temps[y].val;
+ }
+ break;
+ }
+ } else if (temps_are_copies(x, y)) {
switch (c) {
- case TCG_COND_EQ:
- return (uint32_t)x == (uint32_t)y;
- case TCG_COND_NE:
- return (uint32_t)x != (uint32_t)y;
- case TCG_COND_LT:
- return (int32_t)x < (int32_t)y;
- case TCG_COND_GE:
- return (int32_t)x >= (int32_t)y;
- case TCG_COND_LE:
- return (int32_t)x <= (int32_t)y;
case TCG_COND_GT:
- return (int32_t)x > (int32_t)y;
case TCG_COND_LTU:
- return (uint32_t)x < (uint32_t)y;
- case TCG_COND_GEU:
- return (uint32_t)x >= (uint32_t)y;
- case TCG_COND_LEU:
- return (uint32_t)x <= (uint32_t)y;
+ case TCG_COND_LT:
case TCG_COND_GTU:
- return (uint32_t)x > (uint32_t)y;
- }
- break;
- case 64:
- switch (c) {
- case TCG_COND_EQ:
- return (uint64_t)x == (uint64_t)y;
case TCG_COND_NE:
- return (uint64_t)x != (uint64_t)y;
- case TCG_COND_LT:
- return (int64_t)x < (int64_t)y;
+ return 0;
case TCG_COND_GE:
- return (int64_t)x >= (int64_t)y;
+ case TCG_COND_GEU:
case TCG_COND_LE:
- return (int64_t)x <= (int64_t)y;
- case TCG_COND_GT:
- return (int64_t)x > (int64_t)y;
+ case TCG_COND_LEU:
+ case TCG_COND_EQ:
+ return 1;
+ }
+ } else if (temps[y].state == TCG_TEMP_CONST && temps[y].val == 0) {
+ switch (c) {
case TCG_COND_LTU:
- return (uint64_t)x < (uint64_t)y;
+ return 0;
case TCG_COND_GEU:
- return (uint64_t)x >= (uint64_t)y;
- case TCG_COND_LEU:
- return (uint64_t)x <= (uint64_t)y;
- case TCG_COND_GTU:
- return (uint64_t)x > (uint64_t)y;
+ return 1;
+ default:
+ return 2;
}
- break;
+ } else {
+ return 2;
}
fprintf(stderr,
@@ -636,11 +666,9 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr,
args += 3;
break;
CASE_OP_32_64(setcond):
- if (temps[args[1]].state == TCG_TEMP_CONST
- && temps[args[2]].state == TCG_TEMP_CONST) {
+ tmp = do_constant_folding_cond(op, args[1], args[2], args[3]);
+ if (tmp != 2) {
gen_opc_buf[op_index] = op_to_movi(op);
- tmp = do_constant_folding_cond(op, temps[args[1]].val,
- temps[args[2]].val, args[3]);
tcg_opt_gen_movi(gen_args, args[0], tmp);
gen_args += 2;
} else {
@@ -654,10 +682,9 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr,
args += 4;
break;
CASE_OP_32_64(brcond):
- if (temps[args[0]].state == TCG_TEMP_CONST
- && temps[args[1]].state == TCG_TEMP_CONST) {
- if (do_constant_folding_cond(op, temps[args[0]].val,
- temps[args[1]].val, args[2])) {
+ tmp = do_constant_folding_cond(op, args[0], args[1], args[2]);
+ if (tmp != 2) {
+ if (tmp) {
memset(temps, 0, nb_temps * sizeof(struct tcg_temp_info));
gen_opc_buf[op_index] = INDEX_op_br;
gen_args[0] = args[3];
@@ -677,10 +704,8 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr,
args += 4;
break;
CASE_OP_32_64(movcond):
- if (temps[args[1]].state == TCG_TEMP_CONST
- && temps[args[2]].state == TCG_TEMP_CONST) {
- tmp = do_constant_folding_cond(op, temps[args[1]].val,
- temps[args[2]].val, args[5]);
+ tmp = do_constant_folding_cond(op, args[1], args[2], args[5]);
+ if (tmp != 2) {
if (temps_are_copies(args[0], args[4-tmp])) {
gen_opc_buf[op_index] = INDEX_op_nop;
} else if (temps[args[4-tmp]].state == TCG_TEMP_CONST) {
--
1.7.10.4
next prev parent reply other threads:[~2012-09-21 19:43 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-09-21 19:43 [Qemu-devel] [PATCH v2 00/10] tcg/optimize: rework copy propagation Aurelien Jarno
2012-09-21 19:43 ` [Qemu-devel] [PATCH v2 01/10] tcg/optimize: remove TCG_TEMP_ANY Aurelien Jarno
2012-09-21 19:43 ` [Qemu-devel] [PATCH v2 02/10] tcg/optimize: check types in copy propagation Aurelien Jarno
2012-09-21 19:43 ` [Qemu-devel] [PATCH v2 03/10] tcg/optimize: rework copy progagation Aurelien Jarno
2012-09-21 19:43 ` [Qemu-devel] [PATCH v2 04/10] tcg/optimize: do copy propagation for all operations Aurelien Jarno
2012-09-21 19:43 ` [Qemu-devel] [PATCH v2 05/10] tcg/optimize: optimize "op r, a, a => mov r, a" Aurelien Jarno
2012-09-21 19:43 ` [Qemu-devel] [PATCH v2 06/10] tcg/optimize: optimize "op r, a, a => movi r, 0" Aurelien Jarno
2012-09-21 19:43 ` Aurelien Jarno [this message]
2012-09-21 23:17 ` [Qemu-devel] [PATCH v2 07/10] tcg/optimize: further optimize brcond/movcond/setcond Richard Henderson
2012-09-22 9:35 ` Aurelien Jarno
2012-09-22 12:46 ` Richard Henderson
2012-09-21 19:43 ` [Qemu-devel] [PATCH v2 08/10] tcg/optimize: prefer the "op a, a, b" form for commutative ops Aurelien Jarno
2012-09-21 19:43 ` [Qemu-devel] [PATCH v2 09/10] tcg: remove #ifdef #endif around TCGOpcode tests Aurelien Jarno
2012-09-21 19:43 ` [Qemu-devel] [PATCH v2 10/10] tcg/optimize: add constant folding for deposit Aurelien Jarno
2012-09-21 23:22 ` Richard Henderson
2012-09-22 9:41 ` Aurelien Jarno
2012-09-22 12:45 ` Richard Henderson
2012-09-22 14:41 ` Blue Swirl
2012-09-21 23:23 ` [Qemu-devel] [PATCH v2 00/10] tcg/optimize: rework copy propagation Richard Henderson
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=1348256598-8146-8-git-send-email-aurelien@aurel32.net \
--to=aurelien@aurel32.net \
--cc=qemu-devel@nongnu.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 NNTP newsgroup(s).