static void EmitIdenticalObjectComparison(MacroAssembler* masm,
Label* slow,
- Condition cc);
+ Condition cc,
+ bool never_nan_nan);
static void EmitSmiNonsmiComparison(MacroAssembler* masm,
Label* rhs_not_nan,
Label* slow,
// for "identity and not NaN".
static void EmitIdenticalObjectComparison(MacroAssembler* masm,
Label* slow,
- Condition cc) {
+ Condition cc,
+ bool never_nan_nan) {
Label not_identical;
+ Label heap_number, return_equal;
+ Register exp_mask_reg = r5;
__ cmp(r0, Operand(r1));
__ b(ne, ¬_identical);
- Register exp_mask_reg = r5;
- __ mov(exp_mask_reg, Operand(HeapNumber::kExponentMask));
-
- // Test for NaN. Sadly, we can't just compare to Factory::nan_value(),
- // so we do the second best thing - test it ourselves.
- Label heap_number, return_equal;
- // They are both equal and they are not both Smis so both of them are not
- // Smis. If it's not a heap number, then return equal.
- if (cc == lt || cc == gt) {
- __ CompareObjectType(r0, r4, r4, FIRST_JS_OBJECT_TYPE);
- __ b(ge, slow);
- } else {
- __ CompareObjectType(r0, r4, r4, HEAP_NUMBER_TYPE);
- __ b(eq, &heap_number);
- // Comparing JS objects with <=, >= is complicated.
- if (cc != eq) {
- __ cmp(r4, Operand(FIRST_JS_OBJECT_TYPE));
+ // The two objects are identical. If we know that one of them isn't NaN then
+ // we now know they test equal.
+ if (cc != eq || !never_nan_nan) {
+ __ mov(exp_mask_reg, Operand(HeapNumber::kExponentMask));
+
+ // Test for NaN. Sadly, we can't just compare to Factory::nan_value(),
+ // so we do the second best thing - test it ourselves.
+ // They are both equal and they are not both Smis so both of them are not
+ // Smis. If it's not a heap number, then return equal.
+ if (cc == lt || cc == gt) {
+ __ CompareObjectType(r0, r4, r4, FIRST_JS_OBJECT_TYPE);
__ b(ge, slow);
- // Normally here we fall through to return_equal, but undefined is
- // special: (undefined == undefined) == true, but (undefined <= undefined)
- // == false! See ECMAScript 11.8.5.
- if (cc == le || cc == ge) {
- __ cmp(r4, Operand(ODDBALL_TYPE));
- __ b(ne, &return_equal);
- __ LoadRoot(r2, Heap::kUndefinedValueRootIndex);
- __ cmp(r0, Operand(r2));
- __ b(ne, &return_equal);
- if (cc == le) {
- __ mov(r0, Operand(GREATER)); // undefined <= undefined should fail.
- } else {
- __ mov(r0, Operand(LESS)); // undefined >= undefined should fail.
+ } else {
+ __ CompareObjectType(r0, r4, r4, HEAP_NUMBER_TYPE);
+ __ b(eq, &heap_number);
+ // Comparing JS objects with <=, >= is complicated.
+ if (cc != eq) {
+ __ cmp(r4, Operand(FIRST_JS_OBJECT_TYPE));
+ __ b(ge, slow);
+ // Normally here we fall through to return_equal, but undefined is
+ // special: (undefined == undefined) == true, but
+ // (undefined <= undefined) == false! See ECMAScript 11.8.5.
+ if (cc == le || cc == ge) {
+ __ cmp(r4, Operand(ODDBALL_TYPE));
+ __ b(ne, &return_equal);
+ __ LoadRoot(r2, Heap::kUndefinedValueRootIndex);
+ __ cmp(r0, Operand(r2));
+ __ b(ne, &return_equal);
+ if (cc == le) {
+ // undefined <= undefined should fail.
+ __ mov(r0, Operand(GREATER));
+ } else {
+ // undefined >= undefined should fail.
+ __ mov(r0, Operand(LESS));
+ }
+ __ mov(pc, Operand(lr)); // Return.
}
- __ mov(pc, Operand(lr)); // Return.
}
}
}
+
__ bind(&return_equal);
if (cc == lt) {
__ mov(r0, Operand(GREATER)); // Things aren't less than themselves.
}
__ mov(pc, Operand(lr)); // Return.
- // For less and greater we don't have to check for NaN since the result of
- // x < x is false regardless. For the others here is some code to check
- // for NaN.
- if (cc != lt && cc != gt) {
- __ bind(&heap_number);
- // It is a heap number, so return non-equal if it's NaN and equal if it's
- // not NaN.
- // The representation of NaN values has all exponent bits (52..62) set,
- // and not all mantissa bits (0..51) clear.
- // Read top bits of double representation (second word of value).
- __ ldr(r2, FieldMemOperand(r0, HeapNumber::kExponentOffset));
- // Test that exponent bits are all set.
- __ and_(r3, r2, Operand(exp_mask_reg));
- __ cmp(r3, Operand(exp_mask_reg));
- __ b(ne, &return_equal);
-
- // Shift out flag and all exponent bits, retaining only mantissa.
- __ mov(r2, Operand(r2, LSL, HeapNumber::kNonMantissaBitsInTopWord));
- // Or with all low-bits of mantissa.
- __ ldr(r3, FieldMemOperand(r0, HeapNumber::kMantissaOffset));
- __ orr(r0, r3, Operand(r2), SetCC);
- // For equal we already have the right value in r0: Return zero (equal)
- // if all bits in mantissa are zero (it's an Infinity) and non-zero if not
- // (it's a NaN). For <= and >= we need to load r0 with the failing value
- // if it's a NaN.
- if (cc != eq) {
- // All-zero means Infinity means equal.
- __ mov(pc, Operand(lr), LeaveCC, eq); // Return equal
- if (cc == le) {
- __ mov(r0, Operand(GREATER)); // NaN <= NaN should fail.
- } else {
- __ mov(r0, Operand(LESS)); // NaN >= NaN should fail.
+ if (cc != eq || !never_nan_nan) {
+ // For less and greater we don't have to check for NaN since the result of
+ // x < x is false regardless. For the others here is some code to check
+ // for NaN.
+ if (cc != lt && cc != gt) {
+ __ bind(&heap_number);
+ // It is a heap number, so return non-equal if it's NaN and equal if it's
+ // not NaN.
+ // The representation of NaN values has all exponent bits (52..62) set,
+ // and not all mantissa bits (0..51) clear.
+ // Read top bits of double representation (second word of value).
+ __ ldr(r2, FieldMemOperand(r0, HeapNumber::kExponentOffset));
+ // Test that exponent bits are all set.
+ __ and_(r3, r2, Operand(exp_mask_reg));
+ __ cmp(r3, Operand(exp_mask_reg));
+ __ b(ne, &return_equal);
+
+ // Shift out flag and all exponent bits, retaining only mantissa.
+ __ mov(r2, Operand(r2, LSL, HeapNumber::kNonMantissaBitsInTopWord));
+ // Or with all low-bits of mantissa.
+ __ ldr(r3, FieldMemOperand(r0, HeapNumber::kMantissaOffset));
+ __ orr(r0, r3, Operand(r2), SetCC);
+ // For equal we already have the right value in r0: Return zero (equal)
+ // if all bits in mantissa are zero (it's an Infinity) and non-zero if not
+ // (it's a NaN). For <= and >= we need to load r0 with the failing value
+ // if it's a NaN.
+ if (cc != eq) {
+ // All-zero means Infinity means equal.
+ __ mov(pc, Operand(lr), LeaveCC, eq); // Return equal
+ if (cc == le) {
+ __ mov(r0, Operand(GREATER)); // NaN <= NaN should fail.
+ } else {
+ __ mov(r0, Operand(LESS)); // NaN >= NaN should fail.
+ }
}
+ __ mov(pc, Operand(lr)); // Return.
}
- __ mov(pc, Operand(lr)); // Return.
- }
- // No fall through here.
+ // No fall through here.
+ }
__ bind(¬_identical);
}
// Check for oddballs: true, false, null, undefined.
__ cmp(r3, Operand(ODDBALL_TYPE));
__ b(eq, &return_not_equal);
+
+ // Now that we have the types we might as well check for symbol-symbol.
+ // Ensure that no non-strings have the symbol bit set.
+ ASSERT(kNotStringTag + kIsSymbolMask > LAST_TYPE);
+ ASSERT(kSymbolTag != 0);
+ __ and_(r2, r2, Operand(r3));
+ __ tst(r2, Operand(kIsSymbolMask));
+ __ b(ne, &return_not_equal);
}
// Fast negative check for symbol-to-symbol equality.
static void EmitCheckForSymbols(MacroAssembler* masm, Label* slow) {
// r2 is object type of r0.
- __ tst(r2, Operand(kIsNotStringMask));
- __ b(ne, slow);
+ // Ensure that no non-strings have the symbol bit set.
+ ASSERT(kNotStringTag + kIsSymbolMask > LAST_TYPE);
+ ASSERT(kSymbolTag != 0);
__ tst(r2, Operand(kIsSymbolMask));
__ b(eq, slow);
- __ CompareObjectType(r1, r3, r3, FIRST_NONSTRING_TYPE);
- __ b(ge, slow);
+ __ ldr(r3, FieldMemOperand(r1, HeapObject::kMapOffset));
+ __ ldrb(r3, FieldMemOperand(r3, Map::kInstanceTypeOffset));
__ tst(r3, Operand(kIsSymbolMask));
__ b(eq, slow);
// Handle the case where the objects are identical. Either returns the answer
// or goes to slow. Only falls through if the objects were not identical.
- EmitIdenticalObjectComparison(masm, &slow, cc_);
+ EmitIdenticalObjectComparison(masm, &slow, cc_, never_nan_nan_);
// If either is a Smi (we know that not both are), then they can only
// be strictly equal if the other is a HeapNumber.
&slow);
__ bind(&check_for_symbols);
- if (cc_ == eq) {
+ // In the strict case the EmitStrictTwoHeapObjectCompare already took care of
+ // symbols.
+ if (cc_ == eq && !strict_) {
// Either jumps to slow or returns the answer. Assumes that r2 is the type
// of r0 on entry.
EmitCheckForSymbols(masm, &slow);
}
+const char* CompareStub::GetName() {
+ switch(cc_) {
+ case lt: return "CompareStub_LT";
+ case gt: return "CompareStub_GT";
+ case le: return "CompareStub_LE";
+ case ge: return "CompareStub_GE";
+ case ne: {
+ if (strict_) {
+ if (never_nan_nan_) {
+ return "CompareStub_NE_STRICT_NO_NAN";
+ } else {
+ return "CompareStub_NE_STRICT";
+ }
+ } else {
+ if (never_nan_nan_) {
+ return "CompareStub_NE_NO_NAN";
+ } else {
+ return "CompareStub_NE";
+ }
+ }
+ }
+ case eq: {
+ if (strict_) {
+ if (never_nan_nan_) {
+ return "CompareStub_EQ_STRICT_NO_NAN";
+ } else {
+ return "CompareStub_EQ_STRICT";
+ }
+ } else {
+ if (never_nan_nan_) {
+ return "CompareStub_EQ_NO_NAN";
+ } else {
+ return "CompareStub_EQ";
+ }
+ }
+ }
+ default: return "CompareStub";
+ }
+}
+
+
int CompareStub::MinorKey() {
- // Encode the two parameters in a unique 16 bit value.
- ASSERT(static_cast<unsigned>(cc_) >> 28 < (1 << 15));
- return (static_cast<unsigned>(cc_) >> 27) | (strict_ ? 1 : 0);
+ // Encode the three parameters in a unique 16 bit value.
+ ASSERT(static_cast<unsigned>(cc_) < (1 << 14));
+ int nnn_value = (never_nan_nan_ ? 2 : 0);
+ if (cc_ != eq) nnn_value = 0; // Avoid duplicate stubs.
+ return (static_cast<unsigned>(cc_) >> 26) | nnn_value | (strict_ ? 1 : 0);
}
};
+enum NaNInformation {
+ kBothCouldBeNaN,
+ kCantBothBeNaN
+};
+
+
class CompareStub: public CodeStub {
public:
- CompareStub(Condition cc, bool strict) : cc_(cc), strict_(strict) { }
+ CompareStub(Condition cc,
+ bool strict,
+ NaNInformation nan_info = kBothCouldBeNaN) :
+ cc_(cc), strict_(strict), never_nan_nan_(nan_info == kCantBothBeNaN) { }
void Generate(MacroAssembler* masm);
private:
Condition cc_;
bool strict_;
+ // Only used for 'equal' comparisons. Tells the stub that we already know
+ // that at least one side of the comparison is not NaN. This allows the
+ // stub to use object identity in the positive case. We ignore it when
+ // generating the minor key for other comparisons to avoid creating more
+ // stubs.
+ bool never_nan_nan_;
Major MajorKey() { return Compare; }
Register object,
Register scratch);
+ // Unfortunately you have to run without snapshots to see most of these
+ // names in the profile since most compare stubs end up in the snapshot.
+ const char* GetName();
#ifdef DEBUG
void Print() {
PrintF("CompareStub (cc %d), (strict %s)\n",
}
+static bool CouldBeNaN(const Result& result) {
+ if (!result.is_constant()) return true;
+ if (!result.handle()->IsHeapNumber()) return false;
+ return isnan(HeapNumber::cast(*result.handle())->value());
+}
+
+
void CodeGenerator::Comparison(AstNode* node,
Condition cc,
bool strict,
}
ASSERT(cc == less || cc == equal || cc == greater_equal);
- // If either side is a constant smi, optimize the comparison.
- bool left_side_constant_smi =
- left_side.is_constant() && left_side.handle()->IsSmi();
- bool right_side_constant_smi =
- right_side.is_constant() && right_side.handle()->IsSmi();
- bool left_side_constant_null =
- left_side.is_constant() && left_side.handle()->IsNull();
- bool right_side_constant_null =
- right_side.is_constant() && right_side.handle()->IsNull();
+ // If either side is a constant of some sort, we can probably optimize the
+ // comparison.
+ bool left_side_constant_smi = false;
+ bool left_side_constant_null = false;
+ bool left_side_constant_1_char_string = false;
+ if (left_side.is_constant()) {
+ left_side_constant_smi = left_side.handle()->IsSmi();
+ left_side_constant_null = left_side.handle()->IsNull();
+ left_side_constant_1_char_string =
+ (left_side.handle()->IsString() &&
+ (String::cast(*left_side.handle())->length() == 1));
+ }
+ bool right_side_constant_smi = false;
+ bool right_side_constant_null = false;
+ bool right_side_constant_1_char_string = false;
+ if (right_side.is_constant()) {
+ right_side_constant_smi = right_side.handle()->IsSmi();
+ right_side_constant_null = right_side.handle()->IsNull();
+ right_side_constant_1_char_string =
+ (right_side.handle()->IsString() &&
+ (String::cast(*right_side.handle())->length() == 1));
+ }
if (left_side_constant_smi || right_side_constant_smi) {
if (left_side_constant_smi && right_side_constant_smi) {
}
// Setup and call the compare stub.
- CompareStub stub(cc, strict);
+ CompareStub stub(cc, strict, kCantBothBeNaN);
Result result = frame_->CallStub(&stub, &left_side, &right_side);
result.ToRegister();
__ cmp(result.reg(), 0);
operand.Unuse();
dest->Split(not_zero);
}
+ } else if (left_side_constant_1_char_string ||
+ right_side_constant_1_char_string) {
+ if (left_side_constant_1_char_string && right_side_constant_1_char_string) {
+ // Trivial case, comparing two constants.
+ int left_value = String::cast(*left_side.handle())->Get(0);
+ int right_value = String::cast(*right_side.handle())->Get(0);
+ switch (cc) {
+ case less:
+ dest->Goto(left_value < right_value);
+ break;
+ case equal:
+ dest->Goto(left_value == right_value);
+ break;
+ case greater_equal:
+ dest->Goto(left_value >= right_value);
+ break;
+ default:
+ UNREACHABLE();
+ }
+ } else {
+ // Only one side is a constant 1 character string.
+ // If left side is a constant 1-character string, reverse the operands.
+ // Since one side is a constant string, conversion order does not matter.
+ if (left_side_constant_1_char_string) {
+ Result temp = left_side;
+ left_side = right_side;
+ right_side = temp;
+ cc = ReverseCondition(cc);
+ // This may reintroduce greater or less_equal as the value of cc.
+ // CompareStub and the inline code both support all values of cc.
+ }
+ // Implement comparison against a constant string, inlining the case
+ // where both sides are strings.
+ left_side.ToRegister();
+
+ // Here we split control flow to the stub call and inlined cases
+ // before finally splitting it to the control destination. We use
+ // a jump target and branching to duplicate the virtual frame at
+ // the first split. We manually handle the off-frame references
+ // by reconstituting them on the non-fall-through path.
+ JumpTarget is_not_string, is_string;
+ Register left_reg = left_side.reg();
+ Handle<Object> right_val = right_side.handle();
+ __ test(left_side.reg(), Immediate(kSmiTagMask));
+ is_not_string.Branch(zero, &left_side);
+ Result temp = allocator_->Allocate();
+ ASSERT(temp.is_valid());
+ __ mov(temp.reg(),
+ FieldOperand(left_side.reg(), HeapObject::kMapOffset));
+ __ movzx_b(temp.reg(),
+ FieldOperand(temp.reg(), Map::kInstanceTypeOffset));
+ // If we are testing for equality then make use of the symbol shortcut.
+ // Check if the right left hand side has the same type as the left hand
+ // side (which is always a symbol).
+ if (cc == equal) {
+ Label not_a_symbol;
+ ASSERT(kSymbolTag != 0);
+ // Ensure that no non-strings have the symbol bit set.
+ ASSERT(kNotStringTag + kIsSymbolMask > LAST_TYPE);
+ __ test(temp.reg(), Immediate(kIsSymbolMask)); // Test the symbol bit.
+ __ j(zero, ¬_a_symbol);
+ // They are symbols, so do identity compare.
+ __ cmp(left_side.reg(), right_side.handle());
+ dest->true_target()->Branch(equal);
+ dest->false_target()->Branch(not_equal);
+ __ bind(¬_a_symbol);
+ }
+ // If the receiver is not a string of the type we handle call the stub.
+ __ and_(temp.reg(),
+ kIsNotStringMask | kStringRepresentationMask | kStringEncodingMask);
+ __ cmp(temp.reg(), kStringTag | kSeqStringTag | kAsciiStringTag);
+ temp.Unuse();
+ is_string.Branch(equal, &left_side);
+
+ // Setup and call the compare stub.
+ is_not_string.Bind(&left_side);
+ CompareStub stub(cc, strict, kCantBothBeNaN);
+ Result result = frame_->CallStub(&stub, &left_side, &right_side);
+ result.ToRegister();
+ __ cmp(result.reg(), 0);
+ result.Unuse();
+ dest->true_target()->Branch(cc);
+ dest->false_target()->Jump();
+
+ is_string.Bind(&left_side);
+ // Here we know we have a sequential ASCII string.
+ left_side = Result(left_reg);
+ right_side = Result(right_val);
+ Result temp2 = allocator_->Allocate();
+ ASSERT(temp2.is_valid());
+ // Test string equality and comparison.
+ if (cc == equal) {
+ Label comparison_done;
+ __ cmp(FieldOperand(left_side.reg(), String::kLengthOffset),
+ Immediate(1));
+ __ j(not_equal, &comparison_done);
+ __ cmpb(FieldOperand(left_side.reg(), SeqAsciiString::kHeaderSize),
+ String::cast(*right_side.handle())->Get(0));
+ __ bind(&comparison_done);
+ } else {
+ __ mov(temp2.reg(),
+ FieldOperand(left_side.reg(), String::kLengthOffset));
+ __ sub(Operand(temp2.reg()), Immediate(1));
+ Label comparison;
+ // If the length is 0 then our subtraction gave -1 which compares less
+ // than any character.
+ __ j(negative, &comparison);
+ // Otherwise load the first character.
+ __ movzx_b(temp2.reg(),
+ FieldOperand(left_side.reg(), SeqAsciiString::kHeaderSize));
+ __ bind(&comparison);
+ // Compare the first character of the string with out constant
+ // 1-character string.
+ __ cmp(Operand(temp2.reg()),
+ Immediate(String::cast(*right_side.handle())->Get(0)));
+ Label characters_were_different;
+ __ j(not_equal, &characters_were_different);
+ // If the first character is the same then the long string sorts after
+ // the short one.
+ __ cmp(FieldOperand(left_side.reg(), String::kLengthOffset),
+ Immediate(1));
+ __ bind(&characters_were_different);
+ }
+ temp2.Unuse();
+ left_side.Unuse();
+ right_side.Unuse();
+ dest->Split(cc);
+ }
} else {
// Neither side is a constant Smi or null.
// If either side is a non-smi constant, skip the smi check.
bool known_non_smi =
(left_side.is_constant() && !left_side.handle()->IsSmi()) ||
(right_side.is_constant() && !right_side.handle()->IsSmi());
+ NaNInformation nan_info =
+ (CouldBeNaN(left_side) && CouldBeNaN(right_side)) ?
+ kBothCouldBeNaN :
+ kCantBothBeNaN;
left_side.ToRegister();
right_side.ToRegister();
if (known_non_smi) {
// When non-smi, call out to the compare stub.
- CompareStub stub(cc, strict);
+ CompareStub stub(cc, strict, nan_info);
Result answer = frame_->CallStub(&stub, &left_side, &right_side);
if (cc == equal) {
__ test(answer.reg(), Operand(answer.reg()));
temp.Unuse();
is_smi.Branch(zero, taken);
// When non-smi, call out to the compare stub.
- CompareStub stub(cc, strict);
+ CompareStub stub(cc, strict, nan_info);
Result answer = frame_->CallStub(&stub, &left_side, &right_side);
if (cc == equal) {
__ test(answer.reg(), Operand(answer.reg()));
// Test for NaN. Sadly, we can't just compare to Factory::nan_value(),
// so we do the second best thing - test it ourselves.
- Label return_equal;
- Label heap_number;
- // If it's not a heap number, then return equal.
- __ cmp(FieldOperand(edx, HeapObject::kMapOffset),
- Immediate(Factory::heap_number_map()));
- __ j(equal, &heap_number);
- __ bind(&return_equal);
- __ Set(eax, Immediate(0));
- __ ret(0);
+ if (never_nan_nan_) {
+ __ Set(eax, Immediate(0));
+ __ ret(0);
+ } else {
+ Label return_equal;
+ Label heap_number;
+ // If it's not a heap number, then return equal.
+ __ cmp(FieldOperand(edx, HeapObject::kMapOffset),
+ Immediate(Factory::heap_number_map()));
+ __ j(equal, &heap_number);
+ __ bind(&return_equal);
+ __ Set(eax, Immediate(0));
+ __ ret(0);
- __ bind(&heap_number);
- // It is a heap number, so return non-equal if it's NaN and equal if it's
- // not NaN.
- // The representation of NaN values has all exponent bits (52..62) set,
- // and not all mantissa bits (0..51) clear.
- // We only accept QNaNs, which have bit 51 set.
- // Read top bits of double representation (second word of value).
-
- // Value is a QNaN if value & kQuietNaNMask == kQuietNaNMask, i.e.,
- // all bits in the mask are set. We only need to check the word
- // that contains the exponent and high bit of the mantissa.
- ASSERT_NE(0, (kQuietNaNHighBitsMask << 1) & 0x80000000u);
- __ mov(edx, FieldOperand(edx, HeapNumber::kExponentOffset));
- __ xor_(eax, Operand(eax));
- // Shift value and mask so kQuietNaNHighBitsMask applies to topmost bits.
- __ add(edx, Operand(edx));
- __ cmp(edx, kQuietNaNHighBitsMask << 1);
- __ setcc(above_equal, eax);
- __ ret(0);
+ __ bind(&heap_number);
+ // It is a heap number, so return non-equal if it's NaN and equal if
+ // it's not NaN.
+ // The representation of NaN values has all exponent bits (52..62) set,
+ // and not all mantissa bits (0..51) clear.
+ // We only accept QNaNs, which have bit 51 set.
+ // Read top bits of double representation (second word of value).
+
+ // Value is a QNaN if value & kQuietNaNMask == kQuietNaNMask, i.e.,
+ // all bits in the mask are set. We only need to check the word
+ // that contains the exponent and high bit of the mantissa.
+ ASSERT_NE(0, (kQuietNaNHighBitsMask << 1) & 0x80000000u);
+ __ mov(edx, FieldOperand(edx, HeapNumber::kExponentOffset));
+ __ xor_(eax, Operand(eax));
+ // Shift value and mask so kQuietNaNHighBitsMask applies to topmost
+ // bits.
+ __ add(edx, Operand(edx));
+ __ cmp(edx, kQuietNaNHighBitsMask << 1);
+ __ setcc(above_equal, eax);
+ __ ret(0);
+ }
__ bind(¬_identical);
}
}
+// Unfortunately you have to run without snapshots to see most of these
+// names in the profile since most compare stubs end up in the snapshot.
+const char* CompareStub::GetName() {
+ switch (cc_) {
+ case less: return "CompareStub_LT";
+ case greater: return "CompareStub_GT";
+ case less_equal: return "CompareStub_LE";
+ case greater_equal: return "CompareStub_GE";
+ case not_equal: {
+ if (strict_) {
+ if (never_nan_nan_) {
+ return "CompareStub_NE_STRICT_NO_NAN";
+ } else {
+ return "CompareStub_NE_STRICT";
+ }
+ } else {
+ if (never_nan_nan_) {
+ return "CompareStub_NE_NO_NAN";
+ } else {
+ return "CompareStub_NE";
+ }
+ }
+ }
+ case equal: {
+ if (strict_) {
+ if (never_nan_nan_) {
+ return "CompareStub_EQ_STRICT_NO_NAN";
+ } else {
+ return "CompareStub_EQ_STRICT";
+ }
+ } else {
+ if (never_nan_nan_) {
+ return "CompareStub_EQ_NO_NAN";
+ } else {
+ return "CompareStub_EQ";
+ }
+ }
+ }
+ default: return "CompareStub";
+ }
+}
+
+
int CompareStub::MinorKey() {
- // Encode the two parameters in a unique 16 bit value.
- ASSERT(static_cast<unsigned>(cc_) < (1 << 15));
- return (static_cast<unsigned>(cc_) << 1) | (strict_ ? 1 : 0);
+ // Encode the three parameters in a unique 16 bit value.
+ ASSERT(static_cast<unsigned>(cc_) < (1 << 14));
+ int nnn_value = (never_nan_nan_ ? 2 : 0);
+ if (cc_ != equal) nnn_value = 0; // Avoid duplicate stubs.
+ return (static_cast<unsigned>(cc_) << 2) | nnn_value | (strict_ ? 1 : 0);
}
// Is the string a symbol?
__ movzx_b(ebx, FieldOperand(edx, Map::kInstanceTypeOffset));
+ ASSERT(kSymbolTag != 0);
__ test(ebx, Immediate(kIsSymbolMask));
__ j(zero, &slow, not_taken);
// Pushing a result invalidates it (its contents become owned by the
// frame).
void Push(Result* result) {
+ // This assert will trigger if you try to push the same value twice.
+ ASSERT(result->is_valid());
if (result->is_register()) {
Push(result->reg());
} else {
bool Object::IsSymbol() {
if (!this->IsHeapObject()) return false;
uint32_t type = HeapObject::cast(this)->map()->instance_type();
- return (type & (kIsNotStringMask | kIsSymbolMask)) ==
- (kStringTag | kSymbolTag);
+ // Because the symbol tag is non-zero and no non-string types have the
+ // symbol bit set we can test for symbols with a very simple test
+ // operation.
+ ASSERT(kSymbolTag != 0);
+ ASSERT(kNotStringTag + kIsSymbolMask > LAST_TYPE);
+ return (type & kIsSymbolMask) != 0;
}
bool StringShape::IsSymbol() {
ASSERT(valid());
- return (type_ & kIsSymbolMask) == kSymbolTag;
+ ASSERT(kSymbolTag != 0);
+ return (type_ & kIsSymbolMask) != 0;
}
const uint32_t kStringTag = 0x0;
const uint32_t kNotStringTag = 0x80;
-// If bit 7 is clear, bit 5 indicates that the string is a symbol (if set) or
-// not (if cleared).
-const uint32_t kIsSymbolMask = 0x20;
+// Bit 6 indicates that the object is a symbol (if set) or not (if cleared).
+// There are not enough types that the non-string types (with bit 7 set) can
+// have bit 6 set too.
+const uint32_t kIsSymbolMask = 0x40;
const uint32_t kNotSymbolTag = 0x0;
-const uint32_t kSymbolTag = 0x20;
+const uint32_t kSymbolTag = 0x40;
// If bit 7 is clear then bit 2 indicates whether the string consists of
// two-byte characters or one-byte characters.
// Test for NaN. Sadly, we can't just compare to Factory::nan_value(),
// so we do the second best thing - test it ourselves.
- Label return_equal;
- Label heap_number;
- // If it's not a heap number, then return equal.
- __ Cmp(FieldOperand(rdx, HeapObject::kMapOffset),
- Factory::heap_number_map());
- __ j(equal, &heap_number);
- __ bind(&return_equal);
- __ xor_(rax, rax);
- __ ret(0);
+ if (never_nan_nan_) {
+ __ xor_(rax, rax);
+ __ ret(0);
+ } else {
+ Label return_equal;
+ Label heap_number;
+ // If it's not a heap number, then return equal.
+ __ Cmp(FieldOperand(rdx, HeapObject::kMapOffset),
+ Factory::heap_number_map());
+ __ j(equal, &heap_number);
+ __ bind(&return_equal);
+ __ xor_(rax, rax);
+ __ ret(0);
- __ bind(&heap_number);
- // It is a heap number, so return non-equal if it's NaN and equal if it's
- // not NaN.
- // The representation of NaN values has all exponent bits (52..62) set,
- // and not all mantissa bits (0..51) clear.
- // We only allow QNaNs, which have bit 51 set (which also rules out
- // the value being Infinity).
-
- // Value is a QNaN if value & kQuietNaNMask == kQuietNaNMask, i.e.,
- // all bits in the mask are set. We only need to check the word
- // that contains the exponent and high bit of the mantissa.
- ASSERT_NE(0, (kQuietNaNHighBitsMask << 1) & 0x80000000u);
- __ movl(rdx, FieldOperand(rdx, HeapNumber::kExponentOffset));
- __ xorl(rax, rax);
- __ addl(rdx, rdx); // Shift value and mask so mask applies to top bits.
- __ cmpl(rdx, Immediate(kQuietNaNHighBitsMask << 1));
- __ setcc(above_equal, rax);
- __ ret(0);
+ __ bind(&heap_number);
+ // It is a heap number, so return non-equal if it's NaN and equal if
+ // it's not NaN.
+ // The representation of NaN values has all exponent bits (52..62) set,
+ // and not all mantissa bits (0..51) clear.
+ // We only allow QNaNs, which have bit 51 set (which also rules out
+ // the value being Infinity).
+
+ // Value is a QNaN if value & kQuietNaNMask == kQuietNaNMask, i.e.,
+ // all bits in the mask are set. We only need to check the word
+ // that contains the exponent and high bit of the mantissa.
+ ASSERT_NE(0, (kQuietNaNHighBitsMask << 1) & 0x80000000u);
+ __ movl(rdx, FieldOperand(rdx, HeapNumber::kExponentOffset));
+ __ xorl(rax, rax);
+ __ addl(rdx, rdx); // Shift value and mask so mask applies to top bits.
+ __ cmpl(rdx, Immediate(kQuietNaNHighBitsMask << 1));
+ __ setcc(above_equal, rax);
+ __ ret(0);
+ }
__ bind(¬_identical);
}
__ movq(scratch, FieldOperand(object, HeapObject::kMapOffset));
__ movzxbq(scratch,
FieldOperand(scratch, Map::kInstanceTypeOffset));
- __ and_(scratch, Immediate(kIsSymbolMask | kIsNotStringMask));
- __ cmpb(scratch, Immediate(kSymbolTag | kStringTag));
- __ j(not_equal, label);
+ // Ensure that no non-strings have the symbol bit set.
+ ASSERT(kNotStringTag + kIsSymbolMask > LAST_TYPE);
+ ASSERT(kSymbolTag != 0);
+ __ testb(scratch, Immediate(kIsSymbolMask));
+ __ j(zero, label);
}
int CompareStub::MinorKey() {
- // Encode the two parameters in a unique 16 bit value.
- ASSERT(static_cast<unsigned>(cc_) < (1 << 15));
- return (static_cast<unsigned>(cc_) << 1) | (strict_ ? 1 : 0);
+ // Encode the three parameters in a unique 16 bit value.
+ ASSERT(static_cast<unsigned>(cc_) < (1 << 14));
+ int nnn_value = (never_nan_nan_ ? 2 : 0);
+ if (cc_ != equal) nnn_value = 0; // Avoid duplicate stubs.
+ return (static_cast<unsigned>(cc_) << 2) | nnn_value | (strict_ ? 1 : 0);
+}
+
+
+const char* CompareStub::GetName() {
+ switch(cc_) {
+ case less: return "CompareStub_LT";
+ case greater: return "CompareStub_GT";
+ case less_equal: return "CompareStub_LE";
+ case greater_equal: return "CompareStub_GE";
+ case not_equal: {
+ if (strict_) {
+ if (never_nan_nan_) {
+ return "CompareStub_NE_STRICT_NO_NAN";
+ } else {
+ return "CompareStub_NE_STRICT";
+ }
+ } else {
+ if (never_nan_nan_) {
+ return "CompareStub_NE_NO_NAN";
+ } else {
+ return "CompareStub_NE";
+ }
+ }
+ }
+ case equal: {
+ if (strict_) {
+ if (never_nan_nan_) {
+ return "CompareStub_EQ_STRICT_NO_NAN";
+ } else {
+ return "CompareStub_EQ_STRICT";
+ }
+ } else {
+ if (never_nan_nan_) {
+ return "CompareStub_EQ_NO_NAN";
+ } else {
+ return "CompareStub_EQ";
+ }
+ }
+ }
+ default: return "CompareStub";
+ }
}
// Is the string a symbol?
__ j(not_zero, &index_string); // The value in rbx is used at jump target.
+ ASSERT(kSymbolTag != 0);
__ testb(FieldOperand(rdx, Map::kInstanceTypeOffset),
Immediate(kIsSymbolMask));
__ j(zero, &slow);
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-function testBitNot(x) {
+function testBitNot(x, name) {
// The VM constant folds so we use that to check the result.
var expected = eval("~(" + x + ")");
var actual = ~x;
- assertEquals(expected, actual, "x: " + x);
+ assertEquals(expected, actual, "x: " + name);
// Test the path where we can overwrite the result. Use -
// to avoid concatenating strings.
expected = eval("~(" + x + " - 0.01)");
actual = ~(x - 0.01);
- assertEquals(expected, actual, "x - 0.01: " + x);
+ assertEquals(expected, actual, "x - 0.01: " + name);
}
-testBitNot(0);
-testBitNot(1);
-testBitNot(-1);
-testBitNot(100);
-testBitNot(0x40000000);
-testBitNot(0x7fffffff);
-testBitNot(0x80000000);
+testBitNot(0, 0);
+testBitNot(1, 1);
+testBitNot(-1, 1);
+testBitNot(100, 100);
+testBitNot(0x40000000, "0x40000000");
+testBitNot(0x7fffffff, "0x7fffffff");
+testBitNot(0x80000000, "0x80000000");
-testBitNot(2.2);
-testBitNot(-2.3);
-testBitNot(Infinity);
-testBitNot(NaN);
-testBitNot(-Infinity);
-testBitNot(0x40000000 + 0.12345);
-testBitNot(0x40000000 - 0.12345);
-testBitNot(0x7fffffff + 0.12345);
-testBitNot(0x7fffffff - 0.12345);
-testBitNot(0x80000000 + 0.12345);
-testBitNot(0x80000000 - 0.12345);
+testBitNot(2.2, 2.2);
+testBitNot(-2.3, -2.3);
+testBitNot(Infinity, "Infinity");
+testBitNot(NaN, "NaN");
+testBitNot(-Infinity, "-Infinity");
+testBitNot(0x40000000 + 0.12345, "float1");
+testBitNot(0x40000000 - 0.12345, "float2");
+testBitNot(0x7fffffff + 0.12345, "float3");
+testBitNot(0x7fffffff - 0.12345, "float4");
+testBitNot(0x80000000 + 0.12345, "float5");
+testBitNot(0x80000000 - 0.12345, "float6");
-testBitNot("0");
-testBitNot("2.3");
-testBitNot("-9.4");
+testBitNot("0", "string0");
+testBitNot("2.3", "string2.3");
+testBitNot("-9.4", "string-9.4");
// Try to test that we can deal with allocation failures in
--- /dev/null
+// Copyright 2008 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.
+
+// Test the optimized implementation of comparison with single-character
+// strings.
+
+var a = ['', String.fromCharCode(0), ' ', 'e', 'erik', 'f', 'foo', 'g', 'goo',
+ -1, 0, 1, 1.2, -7.9, true, false, 'foo', '0', 'NaN' ];
+for (var i in a) {
+ var x = a[i];
+ var f = 'f';
+
+ assertEquals(x == f, x == 'f', "==" + x);
+ assertEquals(x === f, x === 'f', "===" + x);
+ assertEquals(x < f, x < 'f', "<" + x);
+ assertEquals(x <= f, x <= 'f', "<=" + x);
+ assertEquals(x > f, x > 'f', ">" + x);
+ assertEquals(x >= f, x >= 'f', ">=" + x);
+ assertEquals(f == x, 'f' == x, "==r" + x);
+ assertEquals(f === x, 'f' === x, "===r" + x);
+ assertEquals(f > x, 'f' > x, "<r" + x);
+ assertEquals(f >= x, 'f' >= x, "<=r" + x);
+ assertEquals(f < x, 'f' < x, ">r" + x);
+ assertEquals(f <= x, 'f' <= x, ">=r" + x);
+}
+
assertFalse(x <= NaN, "" + x + " <= NaN");
assertFalse(x >= NaN, "" + x + " >= NaN");
}
+
+var b = ["NaN", "-1", "0", "1", "1.2", "-7.9", "true", "false", "'foo'", "'0'",
+ "'NaN'" ];
+for (var i in b) {
+ var x = b[i];
+ var program =
+ "assertFalse(NaN == " + x + ", 'NaN == ' + " + x + ");\n" +
+ "assertFalse(NaN === " + x + ", 'NaN === ' + " + x + ");\n" +
+ "assertFalse(NaN < " + x + ", 'NaN < ' + " + x + ");\n" +
+ "assertFalse(NaN > " + x + ", 'NaN > ' + " + x + ");\n" +
+ "assertFalse(NaN <= " + x + ", 'NaN <= ' + " + x + ");\n" +
+ "assertFalse(NaN >= " + x + ", 'NaN >= ' + " + x + ");\n" +
+
+ "assertFalse(" + x + " == NaN, '' + " + x + " + ' == NaN');\n" +
+ "assertFalse(" + x + " === NaN, '' + " + x + " + ' === NaN');\n" +
+ "assertFalse(" + x + " < NaN, '' + " + x + " + ' < NaN');\n" +
+ "assertFalse(" + x + " > NaN, '' + " + x + " + ' > NaN');\n" +
+ "assertFalse(" + x + " <= NaN, '' + " + x + " + ' <= NaN');\n" +
+ "assertFalse(" + x + " >= NaN, '' + " + x + " + ' >= NaN');\n";
+ eval(program);
+}
+
projects / platform / upstream / v8.git / commitdiff