Revision: 8834
Author: [email protected]
Date: Thu Aug 4 09:43:20 2011
Log: Revert "tighten invariants of HValue::InferRange"
This change reportedly causes a slowdown or inifinite loop on ARM. Revert
pending investigation.
[email protected]
BUG=
TEST=
Review URL: http://codereview.chromium.org/7566040
http://code.google.com/p/v8/source/detail?r=8834
Modified:
/branches/bleeding_edge/src/hydrogen-instructions.cc
/branches/bleeding_edge/test/mjsunit/math-floor.js
/branches/bleeding_edge/test/mjsunit/math-round.js
=======================================
--- /branches/bleeding_edge/src/hydrogen-instructions.cc Wed Aug 3
03:44:20 2011
+++ /branches/bleeding_edge/src/hydrogen-instructions.cc Thu Aug 4
09:43:20 2011
@@ -862,10 +862,19 @@
Range* HValue::InferRange() {
- // Untagged integer32 cannot be -0, all other representations can.
- Range* result = new Range();
- result->set_can_be_minus_zero(!representation().IsInteger32());
- return result;
+ if (representation().IsTagged()) {
+ // Tagged values are always in int32 range when converted to integer,
+ // but they can contain -0.
+ Range* result = new Range();
+ result->set_can_be_minus_zero(true);
+ return result;
+ } else if (representation().IsNone()) {
+ return NULL;
+ } else {
+ // Untagged integer32 cannot be -0 and we don't compute ranges for
+ // untagged doubles.
+ return new Range();
+ }
}
=======================================
--- /branches/bleeding_edge/test/mjsunit/math-floor.js Wed Aug 3 03:44:20
2011
+++ /branches/bleeding_edge/test/mjsunit/math-floor.js Thu Aug 4 09:43:20
2011
@@ -51,17 +51,6 @@
testFloor(-Infinity, -Infinity);
testFloor(NaN, NaN);
- // Ensure that a negative zero coming from Math.floor is properly handled
- // by other operations.
- function ifloor(x) {
- return 1 / Math.floor(x);
- }
- assertEquals(-Infinity, ifloor(-0));
- assertEquals(-Infinity, ifloor(-0));
- assertEquals(-Infinity, ifloor(-0));
- %OptimizeFunctionOnNextCall(ifloor);
- assertEquals(-Infinity, ifloor(-0));
-
testFloor(0, 0.1);
testFloor(0, 0.49999999999999994);
testFloor(0, 0.5);
@@ -140,19 +129,3 @@
for (var i = 0; i < 500; i++) {
test();
}
-
-
-// Regression test for a bug where a negative zero coming from Math.floor
-// was not properly handled by other operations.
-function floorsum(i, n) {
- var ret = Math.floor(n);
- while (--i > 0) {
- ret += Math.floor(n);
- }
- return ret;
-}
-assertEquals(-0, floorsum(1, -0));
-%OptimizeFunctionOnNextCall(floorsum);
-// The optimized function will deopt. Run it with enough iterations to try
-// to optimize via OSR (triggering the bug).
-assertEquals(-0, floorsum(100000, -0));
=======================================
--- /branches/bleeding_edge/test/mjsunit/math-round.js Wed Aug 3 03:44:20
2011
+++ /branches/bleeding_edge/test/mjsunit/math-round.js Thu Aug 4 09:43:20
2011
@@ -1,4 +1,4 @@
-// Copyright 2011 the V8 project authors. All rights reserved.
+// Copyright 2010 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:
@@ -44,21 +44,6 @@
testRound(-Infinity, -Infinity);
testRound(NaN, NaN);
-// Regression test for a bug where a negative zero coming from Math.round
-// was not properly handled by other operations.
-function roundsum(i, n) {
- var ret = Math.round(n);
- while (--i > 0) {
- ret += Math.round(n);
- }
- return ret;
-}
-assertEquals(-0, roundsum(1, -0));
-%OptimizeFunctionOnNextCall(roundsum);
-// The optimized function will deopt. Run it with enough iterations to try
-// to optimize via OSR (triggering the bug).
-assertEquals(-0, roundsum(100000, -0));
-
testRound(1, 0.5);
testRound(1, 0.7);
testRound(1, 1);
--
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