Merge V8 at 3.8.9.11
Bug: 5688872
Change-Id: Ie3b1dd67a730ec5e82686b7b37dba26f6a9bb24f
diff --git a/src/ia32/code-stubs-ia32.cc b/src/ia32/code-stubs-ia32.cc
index 3a286f0..eded335 100644
--- a/src/ia32/code-stubs-ia32.cc
+++ b/src/ia32/code-stubs-ia32.cc
@@ -128,14 +128,14 @@
// Get the function from the stack.
__ mov(ecx, Operand(esp, 1 * kPointerSize));
- // Setup the object header.
+ // Set up the object header.
Factory* factory = masm->isolate()->factory();
__ mov(FieldOperand(eax, HeapObject::kMapOffset),
factory->function_context_map());
__ mov(FieldOperand(eax, Context::kLengthOffset),
Immediate(Smi::FromInt(length)));
- // Setup the fixed slots.
+ // Set up the fixed slots.
__ Set(ebx, Immediate(0)); // Set to NULL.
__ mov(Operand(eax, Context::SlotOffset(Context::CLOSURE_INDEX)), ecx);
__ mov(Operand(eax, Context::SlotOffset(Context::PREVIOUS_INDEX)), esi);
@@ -179,7 +179,7 @@
// Get the serialized scope info from the stack.
__ mov(ebx, Operand(esp, 2 * kPointerSize));
- // Setup the object header.
+ // Set up the object header.
Factory* factory = masm->isolate()->factory();
__ mov(FieldOperand(eax, HeapObject::kMapOffset),
factory->block_context_map());
@@ -202,7 +202,7 @@
__ mov(ecx, ContextOperand(ecx, Context::CLOSURE_INDEX));
__ bind(&after_sentinel);
- // Setup the fixed slots.
+ // Set up the fixed slots.
__ mov(ContextOperand(eax, Context::CLOSURE_INDEX), ecx);
__ mov(ContextOperand(eax, Context::PREVIOUS_INDEX), esi);
__ mov(ContextOperand(eax, Context::EXTENSION_INDEX), ebx);
@@ -749,7 +749,7 @@
// Exponent word in scratch, exponent part of exponent word in scratch2.
// Zero in ecx.
// We know the exponent is smaller than 30 (biased). If it is less than
- // 0 (biased) then the number is smaller in magnitude than 1.0 * 2^0, ie
+ // 0 (biased) then the number is smaller in magnitude than 1.0 * 2^0, i.e.
// it rounds to zero.
const uint32_t zero_exponent =
(HeapNumber::kExponentBias + 0) << HeapNumber::kExponentShift;
@@ -2938,157 +2938,263 @@
void MathPowStub::Generate(MacroAssembler* masm) {
- // Registers are used as follows:
- // edx = base
- // eax = exponent
- // ecx = temporary, result
-
CpuFeatures::Scope use_sse2(SSE2);
- Label allocate_return, call_runtime;
-
- // Load input parameters.
- __ mov(edx, Operand(esp, 2 * kPointerSize));
- __ mov(eax, Operand(esp, 1 * kPointerSize));
-
- // Save 1 in xmm3 - we need this several times later on.
- __ mov(ecx, Immediate(1));
- __ cvtsi2sd(xmm3, ecx);
-
- Label exponent_nonsmi;
- Label base_nonsmi;
- // If the exponent is a heap number go to that specific case.
- __ JumpIfNotSmi(eax, &exponent_nonsmi);
- __ JumpIfNotSmi(edx, &base_nonsmi);
-
- // Optimized version when both exponent and base are smis.
- Label powi;
- __ SmiUntag(edx);
- __ cvtsi2sd(xmm0, edx);
- __ jmp(&powi);
- // exponent is smi and base is a heapnumber.
- __ bind(&base_nonsmi);
Factory* factory = masm->isolate()->factory();
- __ cmp(FieldOperand(edx, HeapObject::kMapOffset),
- factory->heap_number_map());
- __ j(not_equal, &call_runtime);
+ const Register exponent = eax;
+ const Register base = edx;
+ const Register scratch = ecx;
+ const XMMRegister double_result = xmm3;
+ const XMMRegister double_base = xmm2;
+ const XMMRegister double_exponent = xmm1;
+ const XMMRegister double_scratch = xmm4;
- __ movdbl(xmm0, FieldOperand(edx, HeapNumber::kValueOffset));
+ Label call_runtime, done, exponent_not_smi, int_exponent;
- // Optimized version of pow if exponent is a smi.
- // xmm0 contains the base.
- __ bind(&powi);
- __ SmiUntag(eax);
+ // Save 1 in double_result - we need this several times later on.
+ __ mov(scratch, Immediate(1));
+ __ cvtsi2sd(double_result, scratch);
- // Save exponent in base as we need to check if exponent is negative later.
- // We know that base and exponent are in different registers.
- __ mov(edx, eax);
+ if (exponent_type_ == ON_STACK) {
+ Label base_is_smi, unpack_exponent;
+ // The exponent and base are supplied as arguments on the stack.
+ // This can only happen if the stub is called from non-optimized code.
+ // Load input parameters from stack.
+ __ mov(base, Operand(esp, 2 * kPointerSize));
+ __ mov(exponent, Operand(esp, 1 * kPointerSize));
+
+ __ JumpIfSmi(base, &base_is_smi, Label::kNear);
+ __ cmp(FieldOperand(base, HeapObject::kMapOffset),
+ factory->heap_number_map());
+ __ j(not_equal, &call_runtime);
+
+ __ movdbl(double_base, FieldOperand(base, HeapNumber::kValueOffset));
+ __ jmp(&unpack_exponent, Label::kNear);
+
+ __ bind(&base_is_smi);
+ __ SmiUntag(base);
+ __ cvtsi2sd(double_base, base);
+
+ __ bind(&unpack_exponent);
+ __ JumpIfNotSmi(exponent, &exponent_not_smi, Label::kNear);
+ __ SmiUntag(exponent);
+ __ jmp(&int_exponent);
+
+ __ bind(&exponent_not_smi);
+ __ cmp(FieldOperand(exponent, HeapObject::kMapOffset),
+ factory->heap_number_map());
+ __ j(not_equal, &call_runtime);
+ __ movdbl(double_exponent,
+ FieldOperand(exponent, HeapNumber::kValueOffset));
+ } else if (exponent_type_ == TAGGED) {
+ __ JumpIfNotSmi(exponent, &exponent_not_smi, Label::kNear);
+ __ SmiUntag(exponent);
+ __ jmp(&int_exponent);
+
+ __ bind(&exponent_not_smi);
+ __ movdbl(double_exponent,
+ FieldOperand(exponent, HeapNumber::kValueOffset));
+ }
+
+ if (exponent_type_ != INTEGER) {
+ Label fast_power;
+ // Detect integer exponents stored as double.
+ __ cvttsd2si(exponent, Operand(double_exponent));
+ // Skip to runtime if possibly NaN (indicated by the indefinite integer).
+ __ cmp(exponent, Immediate(0x80000000u));
+ __ j(equal, &call_runtime);
+ __ cvtsi2sd(double_scratch, exponent);
+ // Already ruled out NaNs for exponent.
+ __ ucomisd(double_exponent, double_scratch);
+ __ j(equal, &int_exponent);
+
+ if (exponent_type_ == ON_STACK) {
+ // Detect square root case. Crankshaft detects constant +/-0.5 at
+ // compile time and uses DoMathPowHalf instead. We then skip this check
+ // for non-constant cases of +/-0.5 as these hardly occur.
+ Label continue_sqrt, continue_rsqrt, not_plus_half;
+ // Test for 0.5.
+ // Load double_scratch with 0.5.
+ __ mov(scratch, Immediate(0x3F000000u));
+ __ movd(double_scratch, scratch);
+ __ cvtss2sd(double_scratch, double_scratch);
+ // Already ruled out NaNs for exponent.
+ __ ucomisd(double_scratch, double_exponent);
+ __ j(not_equal, ¬_plus_half, Label::kNear);
+
+ // Calculates square root of base. Check for the special case of
+ // Math.pow(-Infinity, 0.5) == Infinity (ECMA spec, 15.8.2.13).
+ // According to IEEE-754, single-precision -Infinity has the highest
+ // 9 bits set and the lowest 23 bits cleared.
+ __ mov(scratch, 0xFF800000u);
+ __ movd(double_scratch, scratch);
+ __ cvtss2sd(double_scratch, double_scratch);
+ __ ucomisd(double_base, double_scratch);
+ // Comparing -Infinity with NaN results in "unordered", which sets the
+ // zero flag as if both were equal. However, it also sets the carry flag.
+ __ j(not_equal, &continue_sqrt, Label::kNear);
+ __ j(carry, &continue_sqrt, Label::kNear);
+
+ // Set result to Infinity in the special case.
+ __ xorps(double_result, double_result);
+ __ subsd(double_result, double_scratch);
+ __ jmp(&done);
+
+ __ bind(&continue_sqrt);
+ // sqrtsd returns -0 when input is -0. ECMA spec requires +0.
+ __ xorps(double_scratch, double_scratch);
+ __ addsd(double_scratch, double_base); // Convert -0 to +0.
+ __ sqrtsd(double_result, double_scratch);
+ __ jmp(&done);
+
+ // Test for -0.5.
+ __ bind(¬_plus_half);
+ // Load double_exponent with -0.5 by substracting 1.
+ __ subsd(double_scratch, double_result);
+ // Already ruled out NaNs for exponent.
+ __ ucomisd(double_scratch, double_exponent);
+ __ j(not_equal, &fast_power, Label::kNear);
+
+ // Calculates reciprocal of square root of base. Check for the special
+ // case of Math.pow(-Infinity, -0.5) == 0 (ECMA spec, 15.8.2.13).
+ // According to IEEE-754, single-precision -Infinity has the highest
+ // 9 bits set and the lowest 23 bits cleared.
+ __ mov(scratch, 0xFF800000u);
+ __ movd(double_scratch, scratch);
+ __ cvtss2sd(double_scratch, double_scratch);
+ __ ucomisd(double_base, double_scratch);
+ // Comparing -Infinity with NaN results in "unordered", which sets the
+ // zero flag as if both were equal. However, it also sets the carry flag.
+ __ j(not_equal, &continue_rsqrt, Label::kNear);
+ __ j(carry, &continue_rsqrt, Label::kNear);
+
+ // Set result to 0 in the special case.
+ __ xorps(double_result, double_result);
+ __ jmp(&done);
+
+ __ bind(&continue_rsqrt);
+ // sqrtsd returns -0 when input is -0. ECMA spec requires +0.
+ __ xorps(double_exponent, double_exponent);
+ __ addsd(double_exponent, double_base); // Convert -0 to +0.
+ __ sqrtsd(double_exponent, double_exponent);
+ __ divsd(double_result, double_exponent);
+ __ jmp(&done);
+ }
+
+ // Using FPU instructions to calculate power.
+ Label fast_power_failed;
+ __ bind(&fast_power);
+ __ fnclex(); // Clear flags to catch exceptions later.
+ // Transfer (B)ase and (E)xponent onto the FPU register stack.
+ __ sub(esp, Immediate(kDoubleSize));
+ __ movdbl(Operand(esp, 0), double_exponent);
+ __ fld_d(Operand(esp, 0)); // E
+ __ movdbl(Operand(esp, 0), double_base);
+ __ fld_d(Operand(esp, 0)); // B, E
+
+ // Exponent is in st(1) and base is in st(0)
+ // B ^ E = (2^(E * log2(B)) - 1) + 1 = (2^X - 1) + 1 for X = E * log2(B)
+ // FYL2X calculates st(1) * log2(st(0))
+ __ fyl2x(); // X
+ __ fld(0); // X, X
+ __ frndint(); // rnd(X), X
+ __ fsub(1); // rnd(X), X-rnd(X)
+ __ fxch(1); // X - rnd(X), rnd(X)
+ // F2XM1 calculates 2^st(0) - 1 for -1 < st(0) < 1
+ __ f2xm1(); // 2^(X-rnd(X)) - 1, rnd(X)
+ __ fld1(); // 1, 2^(X-rnd(X)) - 1, rnd(X)
+ __ faddp(1); // 1, 2^(X-rnd(X)), rnd(X)
+ // FSCALE calculates st(0) * 2^st(1)
+ __ fscale(); // 2^X, rnd(X)
+ __ fstp(1);
+ // Bail out to runtime in case of exceptions in the status word.
+ __ fnstsw_ax();
+ __ test_b(eax, 0x5F); // We check for all but precision exception.
+ __ j(not_zero, &fast_power_failed, Label::kNear);
+ __ fstp_d(Operand(esp, 0));
+ __ movdbl(double_result, Operand(esp, 0));
+ __ add(esp, Immediate(kDoubleSize));
+ __ jmp(&done);
+
+ __ bind(&fast_power_failed);
+ __ fninit();
+ __ add(esp, Immediate(kDoubleSize));
+ __ jmp(&call_runtime);
+ }
+
+ // Calculate power with integer exponent.
+ __ bind(&int_exponent);
+ const XMMRegister double_scratch2 = double_exponent;
+ __ mov(scratch, exponent); // Back up exponent.
+ __ movsd(double_scratch, double_base); // Back up base.
+ __ movsd(double_scratch2, double_result); // Load double_exponent with 1.
// Get absolute value of exponent.
- Label no_neg;
- __ cmp(eax, 0);
- __ j(greater_equal, &no_neg, Label::kNear);
- __ neg(eax);
+ Label no_neg, while_true, no_multiply;
+ __ test(scratch, scratch);
+ __ j(positive, &no_neg, Label::kNear);
+ __ neg(scratch);
__ bind(&no_neg);
- // Load xmm1 with 1.
- __ movsd(xmm1, xmm3);
- Label while_true;
- Label no_multiply;
-
__ bind(&while_true);
- __ shr(eax, 1);
+ __ shr(scratch, 1);
__ j(not_carry, &no_multiply, Label::kNear);
- __ mulsd(xmm1, xmm0);
+ __ mulsd(double_result, double_scratch);
__ bind(&no_multiply);
- __ mulsd(xmm0, xmm0);
+
+ __ mulsd(double_scratch, double_scratch);
__ j(not_zero, &while_true);
- // base has the original value of the exponent - if the exponent is
- // negative return 1/result.
- __ test(edx, edx);
- __ j(positive, &allocate_return);
- // Special case if xmm1 has reached infinity.
- __ mov(ecx, Immediate(0x7FB00000));
- __ movd(xmm0, ecx);
- __ cvtss2sd(xmm0, xmm0);
- __ ucomisd(xmm0, xmm1);
- __ j(equal, &call_runtime);
- __ divsd(xmm3, xmm1);
- __ movsd(xmm1, xmm3);
- __ jmp(&allocate_return);
+ // scratch has the original value of the exponent - if the exponent is
+ // negative, return 1/result.
+ __ test(exponent, exponent);
+ __ j(positive, &done);
+ __ divsd(double_scratch2, double_result);
+ __ movsd(double_result, double_scratch2);
+ // Test whether result is zero. Bail out to check for subnormal result.
+ // Due to subnormals, x^-y == (1/x)^y does not hold in all cases.
+ __ xorps(double_scratch2, double_scratch2);
+ __ ucomisd(double_scratch2, double_result); // Result cannot be NaN.
+ // double_exponent aliased as double_scratch2 has already been overwritten
+ // and may not have contained the exponent value in the first place when the
+ // exponent is a smi. We reset it with exponent value before bailing out.
+ __ j(not_equal, &done);
+ __ cvtsi2sd(double_exponent, exponent);
- // exponent (or both) is a heapnumber - no matter what we should now work
- // on doubles.
- __ bind(&exponent_nonsmi);
- __ cmp(FieldOperand(eax, HeapObject::kMapOffset),
- factory->heap_number_map());
- __ j(not_equal, &call_runtime);
- __ movdbl(xmm1, FieldOperand(eax, HeapNumber::kValueOffset));
- // Test if exponent is nan.
- __ ucomisd(xmm1, xmm1);
- __ j(parity_even, &call_runtime);
+ // Returning or bailing out.
+ Counters* counters = masm->isolate()->counters();
+ if (exponent_type_ == ON_STACK) {
+ // The arguments are still on the stack.
+ __ bind(&call_runtime);
+ __ TailCallRuntime(Runtime::kMath_pow_cfunction, 2, 1);
- Label base_not_smi;
- Label handle_special_cases;
- __ JumpIfNotSmi(edx, &base_not_smi, Label::kNear);
- __ SmiUntag(edx);
- __ cvtsi2sd(xmm0, edx);
- __ jmp(&handle_special_cases, Label::kNear);
+ // The stub is called from non-optimized code, which expects the result
+ // as heap number in exponent.
+ __ bind(&done);
+ __ AllocateHeapNumber(eax, scratch, base, &call_runtime);
+ __ movdbl(FieldOperand(eax, HeapNumber::kValueOffset), double_result);
+ __ IncrementCounter(counters->math_pow(), 1);
+ __ ret(2 * kPointerSize);
+ } else {
+ __ bind(&call_runtime);
+ {
+ AllowExternalCallThatCantCauseGC scope(masm);
+ __ PrepareCallCFunction(4, scratch);
+ __ movdbl(Operand(esp, 0 * kDoubleSize), double_base);
+ __ movdbl(Operand(esp, 1 * kDoubleSize), double_exponent);
+ __ CallCFunction(
+ ExternalReference::power_double_double_function(masm->isolate()), 4);
+ }
+ // Return value is in st(0) on ia32.
+ // Store it into the (fixed) result register.
+ __ sub(esp, Immediate(kDoubleSize));
+ __ fstp_d(Operand(esp, 0));
+ __ movdbl(double_result, Operand(esp, 0));
+ __ add(esp, Immediate(kDoubleSize));
- __ bind(&base_not_smi);
- __ cmp(FieldOperand(edx, HeapObject::kMapOffset),
- factory->heap_number_map());
- __ j(not_equal, &call_runtime);
- __ mov(ecx, FieldOperand(edx, HeapNumber::kExponentOffset));
- __ and_(ecx, HeapNumber::kExponentMask);
- __ cmp(ecx, Immediate(HeapNumber::kExponentMask));
- // base is NaN or +/-Infinity
- __ j(greater_equal, &call_runtime);
- __ movdbl(xmm0, FieldOperand(edx, HeapNumber::kValueOffset));
-
- // base is in xmm0 and exponent is in xmm1.
- __ bind(&handle_special_cases);
- Label not_minus_half;
- // Test for -0.5.
- // Load xmm2 with -0.5.
- __ mov(ecx, Immediate(0xBF000000));
- __ movd(xmm2, ecx);
- __ cvtss2sd(xmm2, xmm2);
- // xmm2 now has -0.5.
- __ ucomisd(xmm2, xmm1);
- __ j(not_equal, ¬_minus_half, Label::kNear);
-
- // Calculates reciprocal of square root.
- // sqrtsd returns -0 when input is -0. ECMA spec requires +0.
- __ xorps(xmm1, xmm1);
- __ addsd(xmm1, xmm0);
- __ sqrtsd(xmm1, xmm1);
- __ divsd(xmm3, xmm1);
- __ movsd(xmm1, xmm3);
- __ jmp(&allocate_return);
-
- // Test for 0.5.
- __ bind(¬_minus_half);
- // Load xmm2 with 0.5.
- // Since xmm3 is 1 and xmm2 is -0.5 this is simply xmm2 + xmm3.
- __ addsd(xmm2, xmm3);
- // xmm2 now has 0.5.
- __ ucomisd(xmm2, xmm1);
- __ j(not_equal, &call_runtime);
- // Calculates square root.
- // sqrtsd returns -0 when input is -0. ECMA spec requires +0.
- __ xorps(xmm1, xmm1);
- __ addsd(xmm1, xmm0);
- __ sqrtsd(xmm1, xmm1);
-
- __ bind(&allocate_return);
- __ AllocateHeapNumber(ecx, eax, edx, &call_runtime);
- __ movdbl(FieldOperand(ecx, HeapNumber::kValueOffset), xmm1);
- __ mov(eax, ecx);
- __ ret(2 * kPointerSize);
-
- __ bind(&call_runtime);
- __ TailCallRuntime(Runtime::kMath_pow_cfunction, 2, 1);
+ __ bind(&done);
+ __ IncrementCounter(counters->math_pow(), 1);
+ __ ret(0);
+ }
}
@@ -3273,7 +3379,7 @@
__ mov(FieldOperand(eax, i), edx);
}
- // Setup the callee in-object property.
+ // Set up the callee in-object property.
STATIC_ASSERT(Heap::kArgumentsCalleeIndex == 1);
__ mov(edx, Operand(esp, 4 * kPointerSize));
__ mov(FieldOperand(eax, JSObject::kHeaderSize +
@@ -3286,7 +3392,7 @@
Heap::kArgumentsLengthIndex * kPointerSize),
ecx);
- // Setup the elements pointer in the allocated arguments object.
+ // Set up the elements pointer in the allocated arguments object.
// If we allocated a parameter map, edi will point there, otherwise to the
// backing store.
__ lea(edi, Operand(eax, Heap::kArgumentsObjectSize));
@@ -3465,7 +3571,7 @@
// Get the parameters pointer from the stack.
__ mov(edx, Operand(esp, 2 * kPointerSize));
- // Setup the elements pointer in the allocated arguments object and
+ // Set up the elements pointer in the allocated arguments object and
// initialize the header in the elements fixed array.
__ lea(edi, Operand(eax, Heap::kArgumentsObjectSizeStrict));
__ mov(FieldOperand(eax, JSObject::kElementsOffset), edi);
@@ -3617,7 +3723,7 @@
kShortExternalStringMask);
STATIC_ASSERT((kStringTag | kSeqStringTag | kTwoByteStringTag) == 0);
__ j(zero, &seq_two_byte_string, Label::kNear);
- // Any other flat string must be a flat ascii string. None of the following
+ // Any other flat string must be a flat ASCII string. None of the following
// string type tests will succeed if subject is not a string or a short
// external string.
__ and_(ebx, Immediate(kIsNotStringMask |
@@ -3666,16 +3772,16 @@
kStringRepresentationMask | kStringEncodingMask);
STATIC_ASSERT((kSeqStringTag | kTwoByteStringTag) == 0);
__ j(zero, &seq_two_byte_string, Label::kNear);
- // Any other flat string must be sequential ascii or external.
+ // Any other flat string must be sequential ASCII or external.
__ test_b(FieldOperand(ebx, Map::kInstanceTypeOffset),
kStringRepresentationMask);
__ j(not_zero, &external_string);
__ bind(&seq_ascii_string);
- // eax: subject string (flat ascii)
+ // eax: subject string (flat ASCII)
// ecx: RegExp data (FixedArray)
__ mov(edx, FieldOperand(ecx, JSRegExp::kDataAsciiCodeOffset));
- __ Set(ecx, Immediate(1)); // Type is ascii.
+ __ Set(ecx, Immediate(1)); // Type is ASCII.
__ jmp(&check_code, Label::kNear);
__ bind(&seq_two_byte_string);
@@ -3692,7 +3798,7 @@
// eax: subject string
// edx: code
- // ecx: encoding of subject string (1 if ascii, 0 if two_byte);
+ // ecx: encoding of subject string (1 if ASCII, 0 if two_byte);
// Load used arguments before starting to push arguments for call to native
// RegExp code to avoid handling changing stack height.
__ mov(ebx, Operand(esp, kPreviousIndexOffset));
@@ -3701,7 +3807,7 @@
// eax: subject string
// ebx: previous index
// edx: code
- // ecx: encoding of subject string (1 if ascii 0 if two_byte);
+ // ecx: encoding of subject string (1 if ASCII 0 if two_byte);
// All checks done. Now push arguments for native regexp code.
Counters* counters = masm->isolate()->counters();
__ IncrementCounter(counters->regexp_entry_native(), 1);
@@ -3741,7 +3847,7 @@
// esi: original subject string
// eax: underlying subject string
// ebx: previous index
- // ecx: encoding of subject string (1 if ascii 0 if two_byte);
+ // ecx: encoding of subject string (1 if ASCII 0 if two_byte);
// edx: code
// Argument 4: End of string data
// Argument 3: Start of string data
@@ -4369,7 +4475,7 @@
__ JumpIfNotBothSequentialAsciiStrings(edx, eax, ecx, ebx,
&check_unequal_objects);
- // Inline comparison of ascii strings.
+ // Inline comparison of ASCII strings.
if (cc_ == equal) {
StringCompareStub::GenerateFlatAsciiStringEquals(masm,
edx,
@@ -4844,7 +4950,7 @@
Label invoke, handler_entry, exit;
Label not_outermost_js, not_outermost_js_2;
- // Setup frame.
+ // Set up frame.
__ push(ebp);
__ mov(ebp, esp);
@@ -5322,7 +5428,7 @@
STATIC_ASSERT(kSmiTag == 0);
STATIC_ASSERT(kSmiTagSize == 1);
STATIC_ASSERT(kSmiShiftSize == 0);
- // At this point code register contains smi tagged ascii char code.
+ // At this point code register contains smi tagged ASCII char code.
__ mov(result_, FieldOperand(result_,
code_, times_half_pointer_size,
FixedArray::kHeaderSize));
@@ -5369,7 +5475,7 @@
void StringAddStub::Generate(MacroAssembler* masm) {
- Label string_add_runtime, call_builtin;
+ Label call_runtime, call_builtin;
Builtins::JavaScript builtin_id = Builtins::ADD;
// Load the two arguments.
@@ -5378,14 +5484,14 @@
// Make sure that both arguments are strings if not known in advance.
if (flags_ == NO_STRING_ADD_FLAGS) {
- __ JumpIfSmi(eax, &string_add_runtime);
+ __ JumpIfSmi(eax, &call_runtime);
__ CmpObjectType(eax, FIRST_NONSTRING_TYPE, ebx);
- __ j(above_equal, &string_add_runtime);
+ __ j(above_equal, &call_runtime);
// First argument is a a string, test second.
- __ JumpIfSmi(edx, &string_add_runtime);
+ __ JumpIfSmi(edx, &call_runtime);
__ CmpObjectType(edx, FIRST_NONSTRING_TYPE, ebx);
- __ j(above_equal, &string_add_runtime);
+ __ j(above_equal, &call_runtime);
} else {
// Here at least one of the arguments is definitely a string.
// We convert the one that is not known to be a string.
@@ -5436,15 +5542,14 @@
__ add(ebx, ecx);
STATIC_ASSERT(Smi::kMaxValue == String::kMaxLength);
// Handle exceptionally long strings in the runtime system.
- __ j(overflow, &string_add_runtime);
+ __ j(overflow, &call_runtime);
// Use the symbol table when adding two one character strings, as it
// helps later optimizations to return a symbol here.
__ cmp(ebx, Immediate(Smi::FromInt(2)));
__ j(not_equal, &longer_than_two);
- // Check that both strings are non-external ascii strings.
- __ JumpIfNotBothSequentialAsciiStrings(eax, edx, ebx, ecx,
- &string_add_runtime);
+ // Check that both strings are non-external ASCII strings.
+ __ JumpIfNotBothSequentialAsciiStrings(eax, edx, ebx, ecx, &call_runtime);
// Get the two characters forming the new string.
__ movzx_b(ebx, FieldOperand(eax, SeqAsciiString::kHeaderSize));
@@ -5469,11 +5574,7 @@
__ movzx_b(ecx, FieldOperand(edx, SeqAsciiString::kHeaderSize));
__ bind(&make_two_character_string_no_reload);
__ IncrementCounter(counters->string_add_make_two_char(), 1);
- __ AllocateAsciiString(eax, // Result.
- 2, // Length.
- edi, // Scratch 1.
- edx, // Scratch 2.
- &string_add_runtime);
+ __ AllocateAsciiString(eax, 2, edi, edx, &call_runtime);
// Pack both characters in ebx.
__ shl(ecx, kBitsPerByte);
__ or_(ebx, ecx);
@@ -5484,11 +5585,11 @@
__ bind(&longer_than_two);
// Check if resulting string will be flat.
- __ cmp(ebx, Immediate(Smi::FromInt(String::kMinNonFlatLength)));
+ __ cmp(ebx, Immediate(Smi::FromInt(ConsString::kMinLength)));
__ j(below, &string_add_flat_result);
// If result is not supposed to be flat allocate a cons string object. If both
- // strings are ascii the result is an ascii cons string.
+ // strings are ASCII the result is an ASCII cons string.
Label non_ascii, allocated, ascii_data;
__ mov(edi, FieldOperand(eax, HeapObject::kMapOffset));
__ movzx_b(ecx, FieldOperand(edi, Map::kInstanceTypeOffset));
@@ -5500,8 +5601,8 @@
__ test(ecx, Immediate(kStringEncodingMask));
__ j(zero, &non_ascii);
__ bind(&ascii_data);
- // Allocate an acsii cons string.
- __ AllocateAsciiConsString(ecx, edi, no_reg, &string_add_runtime);
+ // Allocate an ASCII cons string.
+ __ AllocateAsciiConsString(ecx, edi, no_reg, &call_runtime);
__ bind(&allocated);
// Fill the fields of the cons string.
if (FLAG_debug_code) __ AbortIfNotSmi(ebx);
@@ -5515,7 +5616,7 @@
__ ret(2 * kPointerSize);
__ bind(&non_ascii);
// At least one of the strings is two-byte. Check whether it happens
- // to contain only ascii characters.
+ // to contain only ASCII characters.
// ecx: first instance type AND second instance type.
// edi: second instance type.
__ test(ecx, Immediate(kAsciiDataHintMask));
@@ -5528,64 +5629,93 @@
__ cmp(edi, kAsciiStringTag | kAsciiDataHintTag);
__ j(equal, &ascii_data);
// Allocate a two byte cons string.
- __ AllocateTwoByteConsString(ecx, edi, no_reg, &string_add_runtime);
+ __ AllocateTwoByteConsString(ecx, edi, no_reg, &call_runtime);
__ jmp(&allocated);
- // Handle creating a flat result. First check that both strings are not
- // external strings.
+ // We cannot encounter sliced strings or cons strings here since:
+ STATIC_ASSERT(SlicedString::kMinLength >= ConsString::kMinLength);
+ // Handle creating a flat result from either external or sequential strings.
+ // Locate the first characters' locations.
// eax: first string
// ebx: length of resulting flat string as a smi
// edx: second string
+ Label first_prepared, second_prepared;
+ Label first_is_sequential, second_is_sequential;
__ bind(&string_add_flat_result);
__ mov(ecx, FieldOperand(eax, HeapObject::kMapOffset));
__ movzx_b(ecx, FieldOperand(ecx, Map::kInstanceTypeOffset));
- __ and_(ecx, kStringRepresentationMask);
- __ cmp(ecx, kExternalStringTag);
- __ j(equal, &string_add_runtime);
- __ mov(ecx, FieldOperand(edx, HeapObject::kMapOffset));
- __ movzx_b(ecx, FieldOperand(ecx, Map::kInstanceTypeOffset));
- __ and_(ecx, kStringRepresentationMask);
- __ cmp(ecx, kExternalStringTag);
- __ j(equal, &string_add_runtime);
- // We cannot encounter sliced strings here since:
- STATIC_ASSERT(SlicedString::kMinLength >= String::kMinNonFlatLength);
- // Now check if both strings are ascii strings.
- // eax: first string
- // ebx: length of resulting flat string as a smi
- // edx: second string
- Label non_ascii_string_add_flat_result;
- STATIC_ASSERT((kStringEncodingMask & kAsciiStringTag) != 0);
- STATIC_ASSERT((kStringEncodingMask & kTwoByteStringTag) == 0);
- __ mov(ecx, FieldOperand(eax, HeapObject::kMapOffset));
- __ test_b(FieldOperand(ecx, Map::kInstanceTypeOffset), kStringEncodingMask);
- __ j(zero, &non_ascii_string_add_flat_result);
- __ mov(ecx, FieldOperand(edx, HeapObject::kMapOffset));
- __ test_b(FieldOperand(ecx, Map::kInstanceTypeOffset), kStringEncodingMask);
- __ j(zero, &string_add_runtime);
+ // ecx: instance type of first string
+ STATIC_ASSERT(kSeqStringTag == 0);
+ __ test_b(ecx, kStringRepresentationMask);
+ __ j(zero, &first_is_sequential, Label::kNear);
+ // Rule out short external string and load string resource.
+ STATIC_ASSERT(kShortExternalStringTag != 0);
+ __ test_b(ecx, kShortExternalStringMask);
+ __ j(not_zero, &call_runtime);
+ __ mov(eax, FieldOperand(eax, ExternalString::kResourceDataOffset));
+ STATIC_ASSERT(SeqAsciiString::kHeaderSize == SeqTwoByteString::kHeaderSize);
+ __ jmp(&first_prepared, Label::kNear);
+ __ bind(&first_is_sequential);
+ __ add(eax, Immediate(SeqAsciiString::kHeaderSize - kHeapObjectTag));
+ __ bind(&first_prepared);
- // Both strings are ascii strings. As they are short they are both flat.
+ __ mov(edi, FieldOperand(edx, HeapObject::kMapOffset));
+ __ movzx_b(edi, FieldOperand(edi, Map::kInstanceTypeOffset));
+ // Check whether both strings have same encoding.
+ // edi: instance type of second string
+ __ xor_(ecx, edi);
+ __ test_b(ecx, kStringEncodingMask);
+ __ j(not_zero, &call_runtime);
+ STATIC_ASSERT(kSeqStringTag == 0);
+ __ test_b(edi, kStringRepresentationMask);
+ __ j(zero, &second_is_sequential, Label::kNear);
+ // Rule out short external string and load string resource.
+ STATIC_ASSERT(kShortExternalStringTag != 0);
+ __ test_b(edi, kShortExternalStringMask);
+ __ j(not_zero, &call_runtime);
+ __ mov(edx, FieldOperand(edx, ExternalString::kResourceDataOffset));
+ STATIC_ASSERT(SeqAsciiString::kHeaderSize == SeqTwoByteString::kHeaderSize);
+ __ jmp(&second_prepared, Label::kNear);
+ __ bind(&second_is_sequential);
+ __ add(edx, Immediate(SeqAsciiString::kHeaderSize - kHeapObjectTag));
+ __ bind(&second_prepared);
+
+ // Push the addresses of both strings' first characters onto the stack.
+ __ push(edx);
+ __ push(eax);
+
+ Label non_ascii_string_add_flat_result, call_runtime_drop_two;
+ // edi: instance type of second string
+ // First string and second string have the same encoding.
+ STATIC_ASSERT(kTwoByteStringTag == 0);
+ __ test_b(edi, kStringEncodingMask);
+ __ j(zero, &non_ascii_string_add_flat_result);
+
+ // Both strings are ASCII strings.
// ebx: length of resulting flat string as a smi
__ SmiUntag(ebx);
- __ AllocateAsciiString(eax, ebx, ecx, edx, edi, &string_add_runtime);
+ __ AllocateAsciiString(eax, ebx, ecx, edx, edi, &call_runtime_drop_two);
// eax: result string
__ mov(ecx, eax);
// Locate first character of result.
__ add(ecx, Immediate(SeqAsciiString::kHeaderSize - kHeapObjectTag));
- // Load first argument and locate first character.
- __ mov(edx, Operand(esp, 2 * kPointerSize));
+ // Load first argument's length and first character location. Account for
+ // values currently on the stack when fetching arguments from it.
+ __ mov(edx, Operand(esp, 4 * kPointerSize));
__ mov(edi, FieldOperand(edx, String::kLengthOffset));
__ SmiUntag(edi);
- __ add(edx, Immediate(SeqAsciiString::kHeaderSize - kHeapObjectTag));
+ __ pop(edx);
// eax: result string
// ecx: first character of result
// edx: first char of first argument
// edi: length of first argument
StringHelper::GenerateCopyCharacters(masm, ecx, edx, edi, ebx, true);
- // Load second argument and locate first character.
- __ mov(edx, Operand(esp, 1 * kPointerSize));
+ // Load second argument's length and first character location. Account for
+ // values currently on the stack when fetching arguments from it.
+ __ mov(edx, Operand(esp, 2 * kPointerSize));
__ mov(edi, FieldOperand(edx, String::kLengthOffset));
__ SmiUntag(edi);
- __ add(edx, Immediate(SeqAsciiString::kHeaderSize - kHeapObjectTag));
+ __ pop(edx);
// eax: result string
// ecx: next character of result
// edx: first char of second argument
@@ -5599,34 +5729,30 @@
// ebx: length of resulting flat string as a smi
// edx: second string
__ bind(&non_ascii_string_add_flat_result);
- __ mov(ecx, FieldOperand(edx, HeapObject::kMapOffset));
- __ test_b(FieldOperand(ecx, Map::kInstanceTypeOffset), kStringEncodingMask);
- __ j(not_zero, &string_add_runtime);
- // Both strings are two byte strings. As they are short they are both
- // flat.
+ // Both strings are two byte strings.
__ SmiUntag(ebx);
- __ AllocateTwoByteString(eax, ebx, ecx, edx, edi, &string_add_runtime);
+ __ AllocateTwoByteString(eax, ebx, ecx, edx, edi, &call_runtime_drop_two);
// eax: result string
__ mov(ecx, eax);
// Locate first character of result.
- __ add(ecx,
- Immediate(SeqTwoByteString::kHeaderSize - kHeapObjectTag));
- // Load first argument and locate first character.
- __ mov(edx, Operand(esp, 2 * kPointerSize));
+ __ add(ecx, Immediate(SeqTwoByteString::kHeaderSize - kHeapObjectTag));
+ // Load second argument's length and first character location. Account for
+ // values currently on the stack when fetching arguments from it.
+ __ mov(edx, Operand(esp, 4 * kPointerSize));
__ mov(edi, FieldOperand(edx, String::kLengthOffset));
__ SmiUntag(edi);
- __ add(edx,
- Immediate(SeqTwoByteString::kHeaderSize - kHeapObjectTag));
+ __ pop(edx);
// eax: result string
// ecx: first character of result
// edx: first char of first argument
// edi: length of first argument
StringHelper::GenerateCopyCharacters(masm, ecx, edx, edi, ebx, false);
- // Load second argument and locate first character.
- __ mov(edx, Operand(esp, 1 * kPointerSize));
+ // Load second argument's length and first character location. Account for
+ // values currently on the stack when fetching arguments from it.
+ __ mov(edx, Operand(esp, 2 * kPointerSize));
__ mov(edi, FieldOperand(edx, String::kLengthOffset));
__ SmiUntag(edi);
- __ add(edx, Immediate(SeqAsciiString::kHeaderSize - kHeapObjectTag));
+ __ pop(edx);
// eax: result string
// ecx: next character of result
// edx: first char of second argument
@@ -5635,8 +5761,11 @@
__ IncrementCounter(counters->string_add_native(), 1);
__ ret(2 * kPointerSize);
+ // Recover stack pointer before jumping to runtime.
+ __ bind(&call_runtime_drop_two);
+ __ Drop(2);
// Just jump to runtime to add the two strings.
- __ bind(&string_add_runtime);
+ __ bind(&call_runtime);
__ TailCallRuntime(Runtime::kStringAdd, 2, 1);
if (call_builtin.is_linked()) {
@@ -5872,7 +6001,7 @@
__ push(mask);
Register temp = mask;
- // Check that the candidate is a non-external ascii string.
+ // Check that the candidate is a non-external ASCII string.
__ mov(temp, FieldOperand(candidate, HeapObject::kMapOffset));
__ movzx_b(temp, FieldOperand(temp, Map::kInstanceTypeOffset));
__ JumpIfInstanceTypeIsNotSequentialAscii(
@@ -5905,10 +6034,25 @@
Register hash,
Register character,
Register scratch) {
- // hash = character + (character << 10);
- __ mov(hash, character);
- __ shl(hash, 10);
- __ add(hash, character);
+ // hash = (seed + character) + ((seed + character) << 10);
+ if (Serializer::enabled()) {
+ ExternalReference roots_array_start =
+ ExternalReference::roots_array_start(masm->isolate());
+ __ mov(scratch, Immediate(Heap::kHashSeedRootIndex));
+ __ mov(scratch, Operand::StaticArray(scratch,
+ times_pointer_size,
+ roots_array_start));
+ __ SmiUntag(scratch);
+ __ add(scratch, character);
+ __ mov(hash, scratch);
+ __ shl(scratch, 10);
+ __ add(hash, scratch);
+ } else {
+ int32_t seed = masm->isolate()->heap()->HashSeed();
+ __ lea(scratch, Operand(character, seed));
+ __ shl(scratch, 10);
+ __ lea(hash, Operand(scratch, character, times_1, seed));
+ }
// hash ^= hash >> 6;
__ mov(scratch, hash);
__ shr(scratch, 6);
@@ -5949,14 +6093,12 @@
__ shl(scratch, 15);
__ add(hash, scratch);
- uint32_t kHashShiftCutOffMask = (1 << (32 - String::kHashShift)) - 1;
- __ and_(hash, kHashShiftCutOffMask);
+ __ and_(hash, String::kHashBitMask);
// if (hash == 0) hash = 27;
Label hash_not_zero;
- __ test(hash, hash);
__ j(not_zero, &hash_not_zero, Label::kNear);
- __ mov(hash, Immediate(27));
+ __ mov(hash, Immediate(StringHasher::kZeroHash));
__ bind(&hash_not_zero);
}
@@ -5988,20 +6130,23 @@
__ JumpIfNotSmi(edx, &runtime);
__ sub(ecx, edx);
__ cmp(ecx, FieldOperand(eax, String::kLengthOffset));
- Label return_eax;
- __ j(equal, &return_eax);
+ Label not_original_string;
+ __ j(not_equal, ¬_original_string, Label::kNear);
+ Counters* counters = masm->isolate()->counters();
+ __ IncrementCounter(counters->sub_string_native(), 1);
+ __ ret(3 * kPointerSize);
+ __ bind(¬_original_string);
// Special handling of sub-strings of length 1 and 2. One character strings
// are handled in the runtime system (looked up in the single character
// cache). Two character strings are looked for in the symbol cache.
- __ SmiUntag(ecx); // Result length is no longer smi.
- __ cmp(ecx, 2);
+ __ cmp(ecx, Immediate(Smi::FromInt(2)));
__ j(greater, &result_longer_than_two);
__ j(less, &runtime);
// Sub string of length 2 requested.
// eax: string
// ebx: instance type
- // ecx: sub string length (value is 2)
+ // ecx: sub string length (smi, value is 2)
// edx: from index (smi)
__ JumpIfInstanceTypeIsNotSequentialAscii(ebx, ebx, &runtime);
@@ -6012,66 +6157,73 @@
FieldOperand(eax, edx, times_1, SeqAsciiString::kHeaderSize + 1));
// Try to lookup two character string in symbol table.
- Label make_two_character_string;
+ Label combine_two_char, save_two_char;
StringHelper::GenerateTwoCharacterSymbolTableProbe(
- masm, ebx, ecx, eax, edx, edi,
- &make_two_character_string, &make_two_character_string);
+ masm, ebx, ecx, eax, edx, edi, &combine_two_char, &save_two_char);
+ __ IncrementCounter(counters->sub_string_native(), 1);
__ ret(3 * kPointerSize);
- __ bind(&make_two_character_string);
- // Setup registers for allocating the two character string.
- __ mov(eax, Operand(esp, 3 * kPointerSize));
- __ mov(ebx, FieldOperand(eax, HeapObject::kMapOffset));
+ __ bind(&combine_two_char);
+ __ shl(ecx, kBitsPerByte);
+ __ or_(ebx, ecx);
+ __ bind(&save_two_char);
+ __ AllocateAsciiString(eax, 2, ecx, edx, &runtime);
+ __ mov_w(FieldOperand(eax, SeqAsciiString::kHeaderSize), ebx);
+ __ IncrementCounter(counters->sub_string_native(), 1);
+ __ ret(3 * kPointerSize);
+
+ __ bind(&result_longer_than_two);
+ // eax: string
+ // ebx: instance type
+ // ecx: sub string length (smi)
+ // edx: from index (smi)
+ // Deal with different string types: update the index if necessary
+ // and put the underlying string into edi.
+ Label underlying_unpacked, sliced_string, seq_or_external_string;
+ // If the string is not indirect, it can only be sequential or external.
+ STATIC_ASSERT(kIsIndirectStringMask == (kSlicedStringTag & kConsStringTag));
+ STATIC_ASSERT(kIsIndirectStringMask != 0);
+ __ test(ebx, Immediate(kIsIndirectStringMask));
+ __ j(zero, &seq_or_external_string, Label::kNear);
+
+ Factory* factory = masm->isolate()->factory();
+ __ test(ebx, Immediate(kSlicedNotConsMask));
+ __ j(not_zero, &sliced_string, Label::kNear);
+ // Cons string. Check whether it is flat, then fetch first part.
+ // Flat cons strings have an empty second part.
+ __ cmp(FieldOperand(eax, ConsString::kSecondOffset),
+ factory->empty_string());
+ __ j(not_equal, &runtime);
+ __ mov(edi, FieldOperand(eax, ConsString::kFirstOffset));
+ // Update instance type.
+ __ mov(ebx, FieldOperand(edi, HeapObject::kMapOffset));
__ movzx_b(ebx, FieldOperand(ebx, Map::kInstanceTypeOffset));
- __ Set(ecx, Immediate(2));
+ __ jmp(&underlying_unpacked, Label::kNear);
+
+ __ bind(&sliced_string);
+ // Sliced string. Fetch parent and adjust start index by offset.
+ __ add(edx, FieldOperand(eax, SlicedString::kOffsetOffset));
+ __ mov(edi, FieldOperand(eax, SlicedString::kParentOffset));
+ // Update instance type.
+ __ mov(ebx, FieldOperand(edi, HeapObject::kMapOffset));
+ __ movzx_b(ebx, FieldOperand(ebx, Map::kInstanceTypeOffset));
+ __ jmp(&underlying_unpacked, Label::kNear);
+
+ __ bind(&seq_or_external_string);
+ // Sequential or external string. Just move string to the expected register.
+ __ mov(edi, eax);
+
+ __ bind(&underlying_unpacked);
if (FLAG_string_slices) {
Label copy_routine;
- // If coming from the make_two_character_string path, the string
- // is too short to be sliced anyways.
- STATIC_ASSERT(2 < SlicedString::kMinLength);
- __ jmp(©_routine);
- __ bind(&result_longer_than_two);
-
- // eax: string
- // ebx: instance type
- // ecx: sub string length
- // edx: from index (smi)
- Label allocate_slice, sliced_string, seq_or_external_string;
- __ cmp(ecx, SlicedString::kMinLength);
+ // edi: underlying subject string
+ // ebx: instance type of underlying subject string
+ // edx: adjusted start index (smi)
+ // ecx: length (smi)
+ __ cmp(ecx, Immediate(Smi::FromInt(SlicedString::kMinLength)));
// Short slice. Copy instead of slicing.
__ j(less, ©_routine);
- // If the string is not indirect, it can only be sequential or external.
- STATIC_ASSERT(kIsIndirectStringMask == (kSlicedStringTag & kConsStringTag));
- STATIC_ASSERT(kIsIndirectStringMask != 0);
- __ test(ebx, Immediate(kIsIndirectStringMask));
- __ j(zero, &seq_or_external_string, Label::kNear);
-
- Factory* factory = masm->isolate()->factory();
- __ test(ebx, Immediate(kSlicedNotConsMask));
- __ j(not_zero, &sliced_string, Label::kNear);
- // Cons string. Check whether it is flat, then fetch first part.
- __ cmp(FieldOperand(eax, ConsString::kSecondOffset),
- factory->empty_string());
- __ j(not_equal, &runtime);
- __ mov(edi, FieldOperand(eax, ConsString::kFirstOffset));
- __ jmp(&allocate_slice, Label::kNear);
-
- __ bind(&sliced_string);
- // Sliced string. Fetch parent and correct start index by offset.
- __ add(edx, FieldOperand(eax, SlicedString::kOffsetOffset));
- __ mov(edi, FieldOperand(eax, SlicedString::kParentOffset));
- __ jmp(&allocate_slice, Label::kNear);
-
- __ bind(&seq_or_external_string);
- // Sequential or external string. Just move string to the correct register.
- __ mov(edi, eax);
-
- __ bind(&allocate_slice);
- // edi: underlying subject string
- // ebx: instance type of original subject string
- // edx: offset
- // ecx: length
// Allocate new sliced string. At this point we do not reload the instance
// type including the string encoding because we simply rely on the info
// provided by the original string. It does not matter if the original
@@ -6088,27 +6240,49 @@
__ AllocateTwoByteSlicedString(eax, ebx, no_reg, &runtime);
__ bind(&set_slice_header);
__ mov(FieldOperand(eax, SlicedString::kOffsetOffset), edx);
- __ SmiTag(ecx);
__ mov(FieldOperand(eax, SlicedString::kLengthOffset), ecx);
__ mov(FieldOperand(eax, SlicedString::kParentOffset), edi);
__ mov(FieldOperand(eax, SlicedString::kHashFieldOffset),
Immediate(String::kEmptyHashField));
- __ jmp(&return_eax);
+ __ IncrementCounter(counters->sub_string_native(), 1);
+ __ ret(3 * kPointerSize);
__ bind(©_routine);
- } else {
- __ bind(&result_longer_than_two);
}
- // eax: string
- // ebx: instance type
- // ecx: result string length
- // Check for flat ascii string
- Label non_ascii_flat;
- __ JumpIfInstanceTypeIsNotSequentialAscii(ebx, ebx, &non_ascii_flat);
+ // edi: underlying subject string
+ // ebx: instance type of underlying subject string
+ // edx: adjusted start index (smi)
+ // ecx: length (smi)
+ // The subject string can only be external or sequential string of either
+ // encoding at this point.
+ Label two_byte_sequential, runtime_drop_two, sequential_string;
+ STATIC_ASSERT(kExternalStringTag != 0);
+ STATIC_ASSERT(kSeqStringTag == 0);
+ __ test_b(ebx, kExternalStringTag);
+ __ j(zero, &sequential_string);
- // Allocate the result.
- __ AllocateAsciiString(eax, ecx, ebx, edx, edi, &runtime);
+ // Handle external string.
+ // Rule out short external strings.
+ STATIC_CHECK(kShortExternalStringTag != 0);
+ __ test_b(ebx, kShortExternalStringMask);
+ __ j(not_zero, &runtime);
+ __ mov(edi, FieldOperand(edi, ExternalString::kResourceDataOffset));
+ // Move the pointer so that offset-wise, it looks like a sequential string.
+ STATIC_ASSERT(SeqTwoByteString::kHeaderSize == SeqAsciiString::kHeaderSize);
+ __ sub(edi, Immediate(SeqTwoByteString::kHeaderSize - kHeapObjectTag));
+
+ __ bind(&sequential_string);
+ // Stash away (adjusted) index and (underlying) string.
+ __ push(edx);
+ __ push(edi);
+ __ SmiUntag(ecx);
+ STATIC_ASSERT((kAsciiStringTag & kStringEncodingMask) != 0);
+ __ test_b(ebx, kStringEncodingMask);
+ __ j(zero, &two_byte_sequential);
+
+ // Sequential ASCII string. Allocate the result.
+ __ AllocateAsciiString(eax, ecx, ebx, edx, edi, &runtime_drop_two);
// eax: result string
// ecx: result string length
@@ -6117,11 +6291,10 @@
__ mov(edi, eax);
__ add(edi, Immediate(SeqAsciiString::kHeaderSize - kHeapObjectTag));
// Load string argument and locate character of sub string start.
- __ mov(esi, Operand(esp, 3 * kPointerSize));
- __ add(esi, Immediate(SeqAsciiString::kHeaderSize - kHeapObjectTag));
- __ mov(ebx, Operand(esp, 2 * kPointerSize)); // from
+ __ pop(esi);
+ __ pop(ebx);
__ SmiUntag(ebx);
- __ add(esi, ebx);
+ __ lea(esi, FieldOperand(esi, ebx, times_1, SeqAsciiString::kHeaderSize));
// eax: result string
// ecx: result length
@@ -6130,20 +6303,12 @@
// esi: character of sub string start
StringHelper::GenerateCopyCharactersREP(masm, edi, esi, ecx, ebx, true);
__ mov(esi, edx); // Restore esi.
- Counters* counters = masm->isolate()->counters();
__ IncrementCounter(counters->sub_string_native(), 1);
__ ret(3 * kPointerSize);
- __ bind(&non_ascii_flat);
- // eax: string
- // ebx: instance type & kStringRepresentationMask | kStringEncodingMask
- // ecx: result string length
- // Check for flat two byte string
- __ cmp(ebx, kSeqStringTag | kTwoByteStringTag);
- __ j(not_equal, &runtime);
-
- // Allocate the result.
- __ AllocateTwoByteString(eax, ecx, ebx, edx, edi, &runtime);
+ __ bind(&two_byte_sequential);
+ // Sequential two-byte string. Allocate the result.
+ __ AllocateTwoByteString(eax, ecx, ebx, edx, edi, &runtime_drop_two);
// eax: result string
// ecx: result string length
@@ -6153,14 +6318,13 @@
__ add(edi,
Immediate(SeqTwoByteString::kHeaderSize - kHeapObjectTag));
// Load string argument and locate character of sub string start.
- __ mov(esi, Operand(esp, 3 * kPointerSize));
- __ add(esi, Immediate(SeqTwoByteString::kHeaderSize - kHeapObjectTag));
- __ mov(ebx, Operand(esp, 2 * kPointerSize)); // from
+ __ pop(esi);
+ __ pop(ebx);
// As from is a smi it is 2 times the value which matches the size of a two
// byte character.
STATIC_ASSERT(kSmiTag == 0);
STATIC_ASSERT(kSmiTagSize + kSmiShiftSize == 1);
- __ add(esi, ebx);
+ __ lea(esi, FieldOperand(esi, ebx, times_1, SeqTwoByteString::kHeaderSize));
// eax: result string
// ecx: result length
@@ -6169,11 +6333,13 @@
// esi: character of sub string start
StringHelper::GenerateCopyCharactersREP(masm, edi, esi, ecx, ebx, false);
__ mov(esi, edx); // Restore esi.
-
- __ bind(&return_eax);
__ IncrementCounter(counters->sub_string_native(), 1);
__ ret(3 * kPointerSize);
+ // Drop pushed values on the stack before tail call.
+ __ bind(&runtime_drop_two);
+ __ Drop(2);
+
// Just jump to runtime to create the sub string.
__ bind(&runtime);
__ TailCallRuntime(Runtime::kSubString, 3, 1);
@@ -6328,10 +6494,10 @@
__ bind(¬_same);
- // Check that both objects are sequential ascii strings.
+ // Check that both objects are sequential ASCII strings.
__ JumpIfNotBothSequentialAsciiStrings(edx, eax, ecx, ebx, &runtime);
- // Compare flat ascii strings.
+ // Compare flat ASCII strings.
// Drop arguments from the stack.
__ pop(ecx);
__ add(esp, Immediate(2 * kPointerSize));
@@ -6565,33 +6731,45 @@
}
-void ICCompareStub::GenerateMiss(MacroAssembler* masm) {
- // Save the registers.
- __ pop(ecx);
- __ push(edx);
- __ push(eax);
- __ push(ecx);
+void ICCompareStub::GenerateKnownObjects(MacroAssembler* masm) {
+ Label miss;
+ __ mov(ecx, edx);
+ __ and_(ecx, eax);
+ __ JumpIfSmi(ecx, &miss, Label::kNear);
+ __ mov(ecx, FieldOperand(eax, HeapObject::kMapOffset));
+ __ mov(ebx, FieldOperand(edx, HeapObject::kMapOffset));
+ __ cmp(ecx, known_map_);
+ __ j(not_equal, &miss, Label::kNear);
+ __ cmp(ebx, known_map_);
+ __ j(not_equal, &miss, Label::kNear);
+
+ __ sub(eax, edx);
+ __ ret(0);
+
+ __ bind(&miss);
+ GenerateMiss(masm);
+}
+
+
+void ICCompareStub::GenerateMiss(MacroAssembler* masm) {
{
// Call the runtime system in a fresh internal frame.
ExternalReference miss = ExternalReference(IC_Utility(IC::kCompareIC_Miss),
masm->isolate());
FrameScope scope(masm, StackFrame::INTERNAL);
- __ push(edx);
+ __ push(edx); // Preserve edx and eax.
+ __ push(eax);
+ __ push(edx); // And also use them as the arguments.
__ push(eax);
__ push(Immediate(Smi::FromInt(op_)));
__ CallExternalReference(miss, 3);
+ // Compute the entry point of the rewritten stub.
+ __ lea(edi, FieldOperand(eax, Code::kHeaderSize));
+ __ pop(eax);
+ __ pop(edx);
}
- // Compute the entry point of the rewritten stub.
- __ lea(edi, FieldOperand(eax, Code::kHeaderSize));
-
- // Restore registers.
- __ pop(ecx);
- __ pop(eax);
- __ pop(edx);
- __ push(ecx);
-
// Do a tail call to the rewritten stub.
__ jmp(edi);
}