Revision: 4806
Author: [email protected]
Date: Mon Jun 7 02:36:30 2010
Log: Revert r4782. Fix issues 728, 732.
Review URL: http://codereview.chromium.org/2701003
http://code.google.com/p/v8/source/detail?r=4806
Modified:
/branches/bleeding_edge/src/arm/ic-arm.cc
/branches/bleeding_edge/src/ia32/ic-ia32.cc
/branches/bleeding_edge/src/objects-inl.h
/branches/bleeding_edge/src/objects.cc
/branches/bleeding_edge/src/objects.h
/branches/bleeding_edge/src/utils.h
/branches/bleeding_edge/src/x64/ic-x64.cc
=======================================
--- /branches/bleeding_edge/src/arm/ic-arm.cc Mon Jun 7 01:27:32 2010
+++ /branches/bleeding_edge/src/arm/ic-arm.cc Mon Jun 7 02:36:30 2010
@@ -849,8 +849,8 @@
// Is the string an array index, with cached numeric value?
__ ldr(r3, FieldMemOperand(r0, String::kHashFieldOffset));
- __ tst(r3, Operand(String::kIsArrayIndexMask));
- __ b(ne, &index_string);
+ __ tst(r3, Operand(String::kContainsCachedArrayIndexMask));
+ __ b(eq, &index_string);
// Is the string a symbol?
// r2: key map
=======================================
--- /branches/bleeding_edge/src/ia32/ic-ia32.cc Mon Jun 7 01:27:32 2010
+++ /branches/bleeding_edge/src/ia32/ic-ia32.cc Mon Jun 7 02:36:30 2010
@@ -404,8 +404,8 @@
__ j(above_equal, &slow);
// Is the string an array index, with cached numeric value?
__ mov(ebx, FieldOperand(eax, String::kHashFieldOffset));
- __ test(ebx, Immediate(String::kIsArrayIndexMask));
- __ j(not_zero, &index_string, not_taken);
+ __ test(ebx, Immediate(String::kContainsCachedArrayIndexMask));
+ __ j(zero, &index_string, not_taken);
// Is the string a symbol?
// ecx: key map.
=======================================
--- /branches/bleeding_edge/src/objects-inl.h Mon Jun 7 01:27:32 2010
+++ /branches/bleeding_edge/src/objects-inl.h Mon Jun 7 02:36:30 2010
@@ -2987,8 +2987,7 @@
: length_(length),
raw_running_hash_(0),
array_index_(0),
- is_array_index_(0 < length_ &&
- length_ <= String::kMaxCachedArrayIndexLength),
+ is_array_index_(0 < length_ && length_ <= String::kMaxArrayIndexSize),
is_first_char_(true),
is_valid_(true) { }
@@ -3051,7 +3050,9 @@
bool String::AsArrayIndex(uint32_t* index) {
uint32_t field = hash_field();
- if (IsHashFieldComputed(field) && !(field & kIsArrayIndexMask)) return
false;
+ if (IsHashFieldComputed(field) && (field & kIsNotArrayIndexMask)) {
+ return false;
+ }
return SlowAsArrayIndex(index);
}
=======================================
--- /branches/bleeding_edge/src/objects.cc Mon Jun 7 01:27:32 2010
+++ /branches/bleeding_edge/src/objects.cc Mon Jun 7 02:36:30 2010
@@ -4850,7 +4850,7 @@
if (length() <= kMaxCachedArrayIndexLength) {
Hash(); // force computation of hash code
uint32_t field = hash_field();
- if ((field & kIsArrayIndexMask) == 0) return false;
+ if ((field & kIsNotArrayIndexMask) != 0) return false;
// Isolate the array index form the full hash field.
*index = (kArrayIndexHashMask & field) >> kHashShift;
return true;
@@ -4869,10 +4869,14 @@
// For array indexes mix the length into the hash as an array index
could
// be zero.
ASSERT(length > 0);
+ ASSERT(length <= String::kMaxArrayIndexSize);
ASSERT(TenToThe(String::kMaxCachedArrayIndexLength) <
(1 << String::kArrayIndexValueBits));
- result |= String::kIsArrayIndexMask;
+ ASSERT(String::kMaxArrayIndexSize < (1 <<
String::kArrayIndexValueBits));
+ result &= ~String::kIsNotArrayIndexMask;
result |= length << String::kArrayIndexHashLengthShift;
+ } else {
+ result |= String::kIsNotArrayIndexMask;
}
return result;
}
=======================================
--- /branches/bleeding_edge/src/objects.h Mon Jun 7 01:27:32 2010
+++ /branches/bleeding_edge/src/objects.h Mon Jun 7 02:36:30 2010
@@ -4194,11 +4194,11 @@
// computed the 2nd bit tells whether the string can be used as an
// array index.
static const int kHashNotComputedMask = 1;
- static const int kIsArrayIndexMask = 1 << 1;
- static const int kNofLengthBitFields = 2;
+ static const int kIsNotArrayIndexMask = 1 << 1;
+ static const int kNofHashBitFields = 2;
// Shift constant retrieving hash code from hash field.
- static const int kHashShift = kNofLengthBitFields;
+ static const int kHashShift = kNofHashBitFields;
// Array index strings this short can keep their index in the hash
// field.
@@ -4207,18 +4207,35 @@
// For strings which are array indexes the hash value has the string
length
// mixed into the hash, mainly to avoid a hash value of zero which would
be
// the case for the string '0'. 24 bits are used for the array index
value.
- static const int kArrayIndexHashLengthShift = 24 + kNofLengthBitFields;
+ static const int kArrayIndexValueBits = 24;
+ static const int kArrayIndexLengthBits =
+ kBitsPerInt - kArrayIndexValueBits - kNofHashBitFields;
+
+ STATIC_CHECK((kArrayIndexLengthBits > 0));
+
+ static const int kArrayIndexHashLengthShift =
+ kArrayIndexValueBits + kNofHashBitFields;
+
static const int kArrayIndexHashMask = (1 << kArrayIndexHashLengthShift)
- 1;
- static const int kArrayIndexValueBits =
- kArrayIndexHashLengthShift - kHashShift;
+
static const int kArrayIndexValueMask =
((1 << kArrayIndexValueBits) - 1) << kHashShift;
+ // Check that kMaxCachedArrayIndexLength + 1 is a power of two so we
+ // could use a mask to test if the length of string is less than or
equal to
+ // kMaxCachedArrayIndexLength.
+ STATIC_CHECK(IS_POWER_OF_TWO(kMaxCachedArrayIndexLength + 1));
+
+ static const int kContainsCachedArrayIndexMask =
+ (~kMaxCachedArrayIndexLength << kArrayIndexHashLengthShift) |
+ kIsNotArrayIndexMask;
+
// Value of empty hash field indicating that the hash is not computed.
- static const int kEmptyHashField = kHashNotComputedMask;
+ static const int kEmptyHashField =
+ kIsNotArrayIndexMask | kHashNotComputedMask;
// Value of hash field containing computed hash equal to zero.
- static const int kZeroHash = 0;
+ static const int kZeroHash = kIsNotArrayIndexMask;
// Maximal string length.
static const int kMaxLength = (1 << (32 - 2)) - 1;
=======================================
--- /branches/bleeding_edge/src/utils.h Fri Jun 4 04:30:55 2010
+++ /branches/bleeding_edge/src/utils.h Mon Jun 7 02:36:30 2010
@@ -37,11 +37,13 @@
//
----------------------------------------------------------------------------
// General helper functions
+#define IS_POWER_OF_TWO(x) (((x) & ((x) - 1)) == 0)
+
// Returns true iff x is a power of 2 (or zero). Cannot be used with the
// maximally negative value of the type T (the -1 overflows).
template <typename T>
static inline bool IsPowerOf2(T x) {
- return (x & (x - 1)) == 0;
+ return IS_POWER_OF_TWO(x);
}
=======================================
--- /branches/bleeding_edge/src/x64/ic-x64.cc Mon Jun 7 01:27:32 2010
+++ /branches/bleeding_edge/src/x64/ic-x64.cc Mon Jun 7 02:36:30 2010
@@ -442,8 +442,8 @@
__ j(above_equal, &slow);
// Is the string an array index, with cached numeric value?
__ movl(rbx, FieldOperand(rax, String::kHashFieldOffset));
- __ testl(rbx, Immediate(String::kIsArrayIndexMask));
- __ j(not_zero, &index_string); // The value in rbx is used at jump
target.
+ __ testl(rbx, Immediate(String::kContainsCachedArrayIndexMask));
+ __ j(zero, &index_string); // The value in rbx is used at jump target.
// Is the string a symbol?
ASSERT(kSymbolTag != 0);
--
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