Revision: 16727
Author: [email protected]
Date: Mon Sep 16 11:28:18 2013 UTC
Log: ARM: Tweak the integer division operation.
BUG=none
TEST=test/mjsunit/lithium/DivI.js
[email protected]
Review URL: https://codereview.chromium.org/23536045
http://code.google.com/p/v8/source/detail?r=16727
Added:
/branches/bleeding_edge/test/mjsunit/lithium/DivI.js
Modified:
/branches/bleeding_edge/src/arm/lithium-arm.cc
/branches/bleeding_edge/src/arm/lithium-codegen-arm.cc
=======================================
--- /dev/null
+++ /branches/bleeding_edge/test/mjsunit/lithium/DivI.js Mon Sep 16
11:28:18 2013 UTC
@@ -0,0 +1,57 @@
+// Copyright 2013 the V8 project authors. All rights reserved.
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+// * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following
+// disclaimer in the documentation and/or other materials provided
+// with the distribution.
+// * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived
+// from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Flags: --allow-natives-syntax --no-use-osr
+
+function foo(a, b) {
+ var result = a / 35;
+ result += 50 / b;
+ result += a / b;
+ result += a / -1;
+ result += a / 1;
+ result += a / 4;
+ result += a / -4;
+ return result / b;
+}
+
+foo(700, 5);
+var r1 = foo(700, 5);
+%OptimizeFunctionOnNextCall(foo);
+var r2 = foo(700, 5);
+
+assertEquals(r1, r2);
+
+function boo(value) {
+ return value / -1;
+}
+
+// Test deoptimization of MinInt / -1.
+assertEquals(2147483600, boo(-2147483600));
+assertEquals(2147483600, boo(-2147483600));
+%OptimizeFunctionOnNextCall(boo);
+assertEquals(2147483600, boo(-2147483600));
+assertEquals(2147483648, boo(-2147483648));
=======================================
--- /branches/bleeding_edge/src/arm/lithium-arm.cc Fri Sep 13 09:13:58 2013
UTC
+++ /branches/bleeding_edge/src/arm/lithium-arm.cc Mon Sep 16 11:28:18 2013
UTC
@@ -1373,9 +1373,8 @@
if (instr->HasPowerOf2Divisor()) {
ASSERT(!instr->CheckFlag(HValue::kCanBeDivByZero));
LOperand* value = UseRegisterAtStart(instr->left());
- LDivI* div =
- new(zone()) LDivI(value, UseOrConstant(instr->right()), NULL);
- return AssignEnvironment(DefineSameAsFirst(div));
+ LDivI* div = new(zone()) LDivI(value, UseConstant(instr->right()),
NULL);
+ return AssignEnvironment(DefineAsRegister(div));
}
LOperand* dividend = UseRegister(instr->left());
LOperand* divisor = UseRegister(instr->right());
=======================================
--- /branches/bleeding_edge/src/arm/lithium-codegen-arm.cc Fri Sep 13
09:13:58 2013 UTC
+++ /branches/bleeding_edge/src/arm/lithium-codegen-arm.cc Mon Sep 16
11:28:18 2013 UTC
@@ -1383,7 +1383,8 @@
void LCodeGen::DoDivI(LDivI* instr) {
if (instr->hydrogen()->HasPowerOf2Divisor()) {
- Register dividend = ToRegister(instr->left());
+ const Register dividend = ToRegister(instr->left());
+ const Register result = ToRegister(instr->result());
int32_t divisor = instr->hydrogen()->right()->GetInteger32Constant();
int32_t test_value = 0;
int32_t power = 0;
@@ -1394,7 +1395,7 @@
} else {
// Check for (0 / -x) that will produce negative zero.
if (instr->hydrogen()->CheckFlag(HValue::kBailoutOnMinusZero)) {
- __ tst(dividend, Operand(dividend));
+ __ cmp(dividend, Operand::Zero());
DeoptimizeIf(eq, instr->environment());
}
// Check for (kMinInt / -1).
@@ -1409,20 +1410,26 @@
if (test_value != 0) {
if (instr->hydrogen()->CheckFlag(
HInstruction::kAllUsesTruncatingToInt32)) {
- __ cmp(dividend, Operand(0));
- __ rsb(dividend, dividend, Operand(0), LeaveCC, lt);
- __ mov(dividend, Operand(dividend, ASR, power));
- if (divisor > 0) __ rsb(dividend, dividend, Operand(0), LeaveCC,
lt);
- if (divisor < 0) __ rsb(dividend, dividend, Operand(0), LeaveCC,
gt);
+ __ sub(result, dividend, Operand::Zero(), SetCC);
+ __ rsb(result, result, Operand::Zero(), LeaveCC, lt);
+ __ mov(result, Operand(result, ASR, power));
+ if (divisor > 0) __ rsb(result, result, Operand::Zero(), LeaveCC,
lt);
+ if (divisor < 0) __ rsb(result, result, Operand::Zero(), LeaveCC,
gt);
return; // Don't fall through to "__ rsb" below.
} else {
// Deoptimize if remainder is not 0.
__ tst(dividend, Operand(test_value));
DeoptimizeIf(ne, instr->environment());
- __ mov(dividend, Operand(dividend, ASR, power));
+ __ mov(result, Operand(dividend, ASR, power));
+ if (divisor < 0) __ rsb(result, result, Operand(0));
+ }
+ } else {
+ if (divisor < 0) {
+ __ rsb(result, dividend, Operand(0));
+ } else {
+ __ Move(result, dividend);
}
}
- if (divisor < 0) __ rsb(dividend, dividend, Operand(0));
return;
}
@@ -1439,12 +1446,15 @@
// Check for (0 / -x) that will produce negative zero.
if (instr->hydrogen()->CheckFlag(HValue::kBailoutOnMinusZero)) {
- Label left_not_zero;
+ Label positive;
+ if (!instr->hydrogen()->CheckFlag(HValue::kCanBeDivByZero)) {
+ // Do the test only if it hadn't be done above.
+ __ cmp(right, Operand::Zero());
+ }
+ __ b(pl, &positive);
__ cmp(left, Operand::Zero());
- __ b(ne, &left_not_zero);
- __ cmp(right, Operand::Zero());
- DeoptimizeIf(mi, instr->environment());
- __ bind(&left_not_zero);
+ DeoptimizeIf(eq, instr->environment());
+ __ bind(&positive);
}
// Check for (kMinInt / -1).
--
--
v8-dev mailing list
[email protected]
http://groups.google.com/group/v8-dev
---
You received this message because you are subscribed to the Google Groups "v8-dev" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to [email protected].
For more options, visit https://groups.google.com/groups/opt_out.
