From: Aurelien Jarno <aurelien@aurel32.net>
To: qemu-devel@nongnu.org
Subject: [Qemu-devel] [5680] target-mips: optimize gen_arith()/gen_arith_imm()
Date: Tue, 11 Nov 2008 11:50:18 +0000 [thread overview]
Message-ID: <E1KzrlC-0003y1-7Q@cvs.savannah.gnu.org> (raw)
Revision: 5680
http://svn.sv.gnu.org/viewvc/?view=rev&root=qemu&revision=5680
Author: aurel32
Date: 2008-11-11 11:50:17 +0000 (Tue, 11 Nov 2008)
Log Message:
-----------
target-mips: optimize gen_arith()/gen_arith_imm()
Optimize code generation in gen_arith()/gen_arith_imm():
- Don't do sign extension when the value is already guaranteed to be
sign extended (otherwise, results are marked as UNPREDICTABLE).
- When the value is sign extended, compare the value to 0 instead of
testing bit 31/63.
- Temp variables are valid up to and *including* the brcond instruction.
Use them instead of temp local variables.
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Modified Paths:
--------------
trunk/target-mips/translate.c
Modified: trunk/target-mips/translate.c
===================================================================
--- trunk/target-mips/translate.c 2008-11-11 11:47:06 UTC (rev 5679)
+++ trunk/target-mips/translate.c 2008-11-11 11:50:17 UTC (rev 5680)
@@ -1333,7 +1333,7 @@
switch (opc) {
case OPC_ADDI:
{
- TCGv r_tmp1 = tcg_temp_local_new(TCG_TYPE_TL);
+ TCGv r_tmp1 = tcg_temp_new(TCG_TYPE_TL);
TCGv r_tmp2 = tcg_temp_new(TCG_TYPE_TL);
int l1 = gen_new_label();
@@ -1341,24 +1341,21 @@
tcg_gen_ext32s_tl(r_tmp1, t0);
tcg_gen_addi_tl(t0, r_tmp1, uimm);
- tcg_gen_xori_tl(r_tmp1, r_tmp1, uimm);
- tcg_gen_xori_tl(r_tmp1, r_tmp1, -1);
+ tcg_gen_xori_tl(r_tmp1, r_tmp1, ~uimm);
tcg_gen_xori_tl(r_tmp2, t0, uimm);
tcg_gen_and_tl(r_tmp1, r_tmp1, r_tmp2);
tcg_temp_free(r_tmp2);
- tcg_gen_shri_tl(r_tmp1, r_tmp1, 31);
- tcg_gen_brcondi_tl(TCG_COND_EQ, r_tmp1, 0, l1);
- tcg_temp_free(r_tmp1);
+ tcg_gen_brcondi_tl(TCG_COND_GE, r_tmp1, 0, l1);
/* operands of same sign, result different sign */
generate_exception(ctx, EXCP_OVERFLOW);
gen_set_label(l1);
+ tcg_temp_free(r_tmp1);
tcg_gen_ext32s_tl(t0, t0);
}
opn = "addi";
break;
case OPC_ADDIU:
- tcg_gen_ext32s_tl(t0, t0);
tcg_gen_addi_tl(t0, t0, uimm);
tcg_gen_ext32s_tl(t0, t0);
opn = "addiu";
@@ -1366,7 +1363,7 @@
#if defined(TARGET_MIPS64)
case OPC_DADDI:
{
- TCGv r_tmp1 = tcg_temp_local_new(TCG_TYPE_TL);
+ TCGv r_tmp1 = tcg_temp_new(TCG_TYPE_TL);
TCGv r_tmp2 = tcg_temp_new(TCG_TYPE_TL);
int l1 = gen_new_label();
@@ -1374,17 +1371,15 @@
tcg_gen_mov_tl(r_tmp1, t0);
tcg_gen_addi_tl(t0, t0, uimm);
- tcg_gen_xori_tl(r_tmp1, r_tmp1, uimm);
- tcg_gen_xori_tl(r_tmp1, r_tmp1, -1);
+ tcg_gen_xori_tl(r_tmp1, r_tmp1, ~uimm);
tcg_gen_xori_tl(r_tmp2, t0, uimm);
tcg_gen_and_tl(r_tmp1, r_tmp1, r_tmp2);
tcg_temp_free(r_tmp2);
- tcg_gen_shri_tl(r_tmp1, r_tmp1, 63);
- tcg_gen_brcondi_tl(TCG_COND_EQ, r_tmp1, 0, l1);
- tcg_temp_free(r_tmp1);
+ tcg_gen_brcondi_tl(TCG_COND_GE, r_tmp1, 0, l1);
/* operands of same sign, result different sign */
generate_exception(ctx, EXCP_OVERFLOW);
gen_set_label(l1);
+ tcg_temp_free(r_tmp1);
}
opn = "daddi";
break;
@@ -1417,7 +1412,6 @@
opn = "lui";
break;
case OPC_SLL:
- tcg_gen_ext32u_tl(t0, t0);
tcg_gen_shli_tl(t0, t0, uimm);
tcg_gen_ext32s_tl(t0, t0);
opn = "sll";
@@ -1425,15 +1419,17 @@
case OPC_SRA:
tcg_gen_ext32s_tl(t0, t0);
tcg_gen_sari_tl(t0, t0, uimm);
- tcg_gen_ext32s_tl(t0, t0);
opn = "sra";
break;
case OPC_SRL:
switch ((ctx->opcode >> 21) & 0x1f) {
case 0:
- tcg_gen_ext32u_tl(t0, t0);
- tcg_gen_shri_tl(t0, t0, uimm);
- tcg_gen_ext32s_tl(t0, t0);
+ if (uimm != 0) {
+ tcg_gen_ext32u_tl(t0, t0);
+ tcg_gen_shri_tl(t0, t0, uimm);
+ } else {
+ tcg_gen_ext32s_tl(t0, t0);
+ }
opn = "srl";
break;
case 1:
@@ -1449,9 +1445,12 @@
}
opn = "rotr";
} else {
- tcg_gen_ext32u_tl(t0, t0);
- tcg_gen_shri_tl(t0, t0, uimm);
- tcg_gen_ext32s_tl(t0, t0);
+ if (uimm != 0) {
+ tcg_gen_ext32u_tl(t0, t0);
+ tcg_gen_shri_tl(t0, t0, uimm);
+ } else {
+ tcg_gen_ext32s_tl(t0, t0);
+ }
opn = "srl";
}
break;
@@ -1562,7 +1561,7 @@
switch (opc) {
case OPC_ADD:
{
- TCGv r_tmp1 = tcg_temp_local_new(TCG_TYPE_TL);
+ TCGv r_tmp1 = tcg_temp_new(TCG_TYPE_TL);
TCGv r_tmp2 = tcg_temp_new(TCG_TYPE_TL);
int l1 = gen_new_label();
@@ -1576,27 +1575,24 @@
tcg_gen_xor_tl(r_tmp2, t0, t1);
tcg_gen_and_tl(r_tmp1, r_tmp1, r_tmp2);
tcg_temp_free(r_tmp2);
- tcg_gen_shri_tl(r_tmp1, r_tmp1, 31);
- tcg_gen_brcondi_tl(TCG_COND_EQ, r_tmp1, 0, l1);
- tcg_temp_free(r_tmp1);
+ tcg_gen_brcondi_tl(TCG_COND_GE, r_tmp1, 0, l1);
/* operands of same sign, result different sign */
generate_exception(ctx, EXCP_OVERFLOW);
gen_set_label(l1);
+ tcg_temp_free(r_tmp1);
tcg_gen_ext32s_tl(t0, t0);
}
opn = "add";
break;
case OPC_ADDU:
- tcg_gen_ext32s_tl(t0, t0);
- tcg_gen_ext32s_tl(t1, t1);
tcg_gen_add_tl(t0, t0, t1);
tcg_gen_ext32s_tl(t0, t0);
opn = "addu";
break;
case OPC_SUB:
{
- TCGv r_tmp1 = tcg_temp_local_new(TCG_TYPE_TL);
+ TCGv r_tmp1 = tcg_temp_new(TCG_TYPE_TL);
TCGv r_tmp2 = tcg_temp_new(TCG_TYPE_TL);
int l1 = gen_new_label();
@@ -1609,20 +1605,17 @@
tcg_gen_xor_tl(r_tmp1, r_tmp1, t0);
tcg_gen_and_tl(r_tmp1, r_tmp1, r_tmp2);
tcg_temp_free(r_tmp2);
- tcg_gen_shri_tl(r_tmp1, r_tmp1, 31);
- tcg_gen_brcondi_tl(TCG_COND_EQ, r_tmp1, 0, l1);
- tcg_temp_free(r_tmp1);
+ tcg_gen_brcondi_tl(TCG_COND_GE, r_tmp1, 0, l1);
/* operands of different sign, first operand and result different sign */
generate_exception(ctx, EXCP_OVERFLOW);
gen_set_label(l1);
+ tcg_temp_free(r_tmp1);
tcg_gen_ext32s_tl(t0, t0);
}
opn = "sub";
break;
case OPC_SUBU:
- tcg_gen_ext32s_tl(t0, t0);
- tcg_gen_ext32s_tl(t1, t1);
tcg_gen_sub_tl(t0, t0, t1);
tcg_gen_ext32s_tl(t0, t0);
opn = "subu";
@@ -1630,7 +1623,7 @@
#if defined(TARGET_MIPS64)
case OPC_DADD:
{
- TCGv r_tmp1 = tcg_temp_local_new(TCG_TYPE_TL);
+ TCGv r_tmp1 = tcg_temp_new(TCG_TYPE_TL);
TCGv r_tmp2 = tcg_temp_new(TCG_TYPE_TL);
int l1 = gen_new_label();
@@ -1643,12 +1636,11 @@
tcg_gen_xor_tl(r_tmp2, t0, t1);
tcg_gen_and_tl(r_tmp1, r_tmp1, r_tmp2);
tcg_temp_free(r_tmp2);
- tcg_gen_shri_tl(r_tmp1, r_tmp1, 63);
- tcg_gen_brcondi_tl(TCG_COND_EQ, r_tmp1, 0, l1);
- tcg_temp_free(r_tmp1);
+ tcg_gen_brcondi_tl(TCG_COND_GE, r_tmp1, 0, l1);
/* operands of same sign, result different sign */
generate_exception(ctx, EXCP_OVERFLOW);
gen_set_label(l1);
+ tcg_temp_free(r_tmp1);
}
opn = "dadd";
break;
@@ -1658,7 +1650,7 @@
break;
case OPC_DSUB:
{
- TCGv r_tmp1 = tcg_temp_local_new(TCG_TYPE_TL);
+ TCGv r_tmp1 = tcg_temp_new(TCG_TYPE_TL);
TCGv r_tmp2 = tcg_temp_new(TCG_TYPE_TL);
int l1 = gen_new_label();
@@ -1670,12 +1662,11 @@
tcg_gen_xor_tl(r_tmp1, r_tmp1, t0);
tcg_gen_and_tl(r_tmp1, r_tmp1, r_tmp2);
tcg_temp_free(r_tmp2);
- tcg_gen_shri_tl(r_tmp1, r_tmp1, 63);
- tcg_gen_brcondi_tl(TCG_COND_EQ, r_tmp1, 0, l1);
- tcg_temp_free(r_tmp1);
+ tcg_gen_brcondi_tl(TCG_COND_GE, r_tmp1, 0, l1);
/* operands of different sign, first operand and result different sign */
generate_exception(ctx, EXCP_OVERFLOW);
gen_set_label(l1);
+ tcg_temp_free(r_tmp1);
}
opn = "dsub";
break;
@@ -1710,8 +1701,6 @@
opn = "xor";
break;
case OPC_MUL:
- tcg_gen_ext32s_tl(t0, t0);
- tcg_gen_ext32s_tl(t1, t1);
tcg_gen_mul_tl(t0, t0, t1);
tcg_gen_ext32s_tl(t0, t0);
opn = "mul";
@@ -1737,8 +1726,6 @@
opn = "movz";
goto print;
case OPC_SLLV:
- tcg_gen_ext32u_tl(t0, t0);
- tcg_gen_ext32u_tl(t1, t1);
tcg_gen_andi_tl(t0, t0, 0x1f);
tcg_gen_shl_tl(t0, t1, t0);
tcg_gen_ext32s_tl(t0, t0);
@@ -1748,7 +1735,6 @@
tcg_gen_ext32s_tl(t1, t1);
tcg_gen_andi_tl(t0, t0, 0x1f);
tcg_gen_sar_tl(t0, t1, t0);
- tcg_gen_ext32s_tl(t0, t0);
opn = "srav";
break;
case OPC_SRLV:
reply other threads:[~2008-11-11 11:50 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
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=E1KzrlC-0003y1-7Q@cvs.savannah.gnu.org \
--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).