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	 3cf50539ec
			
		
	
	
		3cf50539ec
		
	
	
	
	
		
			
			The special empty value (that we use for array holes, Optional<Value> when empty and a few other other placeholder/sentinel tasks) still exists, but you now create one via JS::js_special_empty_value() and check for it with Value::is_special_empty_value(). The main idea here is to make it very unlikely to accidentally create an unexpected special empty value.
		
			
				
	
	
		
			116 lines
		
	
	
	
		
			4.3 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			116 lines
		
	
	
	
		
			4.3 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
| /*
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|  * Copyright (c) 2022, David Tuin <davidot@serenityos.org>
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|  *
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|  * SPDX-License-Identifier: BSD-2-Clause
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|  */
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| 
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| #include <LibJS/Runtime/Value.h>
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| #include <LibJS/Runtime/ValueInlines.h>
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| #include <LibTest/TestCase.h>
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| 
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| using namespace JS;
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| 
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| template<typename Type>
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| static void test_nullptr_input()
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| {
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|     Type* ptr = nullptr;
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|     JS::Value val { ptr };
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|     EXPECT(val.is_null());
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|     EXPECT(!val.is_object());
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|     EXPECT(!val.is_string());
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|     EXPECT(!val.is_bigint());
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|     EXPECT(!val.is_symbol());
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|     EXPECT(!val.is_accessor());
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|     EXPECT(!val.is_cell());
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|     EXPECT(!val.is_number());
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|     EXPECT(!val.is_undefined());
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| }
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| 
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| #define TEST_NULLPTR_INPUT(type)          \
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|     TEST_CASE(value_nullptr_input_##type) \
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|     {                                     \
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|         test_nullptr_input<type>();       \
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|     }
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| 
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| TEST_NULLPTR_INPUT(Object);
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| TEST_NULLPTR_INPUT(PrimitiveString);
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| TEST_NULLPTR_INPUT(Symbol);
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| TEST_NULLPTR_INPUT(BigInt);
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| TEST_NULLPTR_INPUT(Accessor);
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| 
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| #undef TEST_NULLPTR_INPUT
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| 
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| TEST_CASE(valid_pointer_in_gives_same_pointer_out)
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| {
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|     if (sizeof(void*) < sizeof(double))
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|         return;
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| 
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| #define EXPECT_POINTER_TO_SURVIVE(input)                                           \
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|     {                                                                              \
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|         JS::Value value(reinterpret_cast<Object*>(static_cast<u64>(input)));       \
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|         EXPECT(value.is_object());                                                 \
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|         EXPECT(!value.is_null());                                                  \
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|         auto extracted_pointer = JS::Value::extract_pointer_bits(value.encoded()); \
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|         EXPECT_EQ(static_cast<u64>(input), extracted_pointer);                     \
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|     }
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| 
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|     EXPECT_POINTER_TO_SURVIVE(0x1);
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|     EXPECT_POINTER_TO_SURVIVE(0x10);
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|     EXPECT_POINTER_TO_SURVIVE(0x100);
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|     EXPECT_POINTER_TO_SURVIVE(0x00007fffffffffff);
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|     EXPECT_POINTER_TO_SURVIVE(0x0000700000000000);
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|     EXPECT_POINTER_TO_SURVIVE(0x0000100000000000);
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| 
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| #if ARCH(X86_64)
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|     // On x86-64, the top 16 bits of pointers are equal to bit 47.
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|     EXPECT_POINTER_TO_SURVIVE(0xffff800000000000);
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|     EXPECT_POINTER_TO_SURVIVE(0xffff800000000001);
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|     EXPECT_POINTER_TO_SURVIVE(0xffff800000000010);
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| #elif ARCH(AARCH64)
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|     // ... but they should contain zeroes on AArch64.
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|     EXPECT_POINTER_TO_SURVIVE(0x0000800000000000);
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|     EXPECT_POINTER_TO_SURVIVE(0x0000800000000001);
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|     EXPECT_POINTER_TO_SURVIVE(0x0000800000000010);
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| #endif
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| 
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| #undef EXPECT_POINTER_TO_SURVIVE
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| }
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| 
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| TEST_CASE(non_canon_nans)
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| {
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| #define EXPECT_TO_BE_NAN(input)                \
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|     {                                          \
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|         Value val { bit_cast<double>(input) }; \
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|         EXPECT(val.is_nan());                  \
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|         EXPECT(val.is_number());               \
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|         EXPECT(!val.is_integral_number());     \
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|         EXPECT(!val.is_finite_number());       \
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|         EXPECT(!val.is_infinity());            \
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|         EXPECT(!val.is_special_empty_value()); \
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|         EXPECT(!val.is_nullish());             \
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|     }
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| 
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|     EXPECT_TO_BE_NAN(GC::CANON_NAN_BITS | 0x1);
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|     EXPECT_TO_BE_NAN(GC::CANON_NAN_BITS | 0x10);
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|     EXPECT_TO_BE_NAN(GC::CANON_NAN_BITS | (NULL_TAG << GC::TAG_SHIFT));
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|     EXPECT_TO_BE_NAN(GC::CANON_NAN_BITS | (UNDEFINED_TAG << GC::TAG_SHIFT));
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|     EXPECT_TO_BE_NAN(GC::CANON_NAN_BITS | (INT32_TAG << GC::TAG_SHIFT) | 0x88);
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|     EXPECT_TO_BE_NAN(GC::CANON_NAN_BITS | (OBJECT_TAG << GC::TAG_SHIFT));
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|     EXPECT_TO_BE_NAN(GC::CANON_NAN_BITS | (OBJECT_TAG << GC::TAG_SHIFT) | 0x1230);
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|     EXPECT_TO_BE_NAN(GC::CANON_NAN_BITS | (STRING_TAG << GC::TAG_SHIFT));
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|     EXPECT_TO_BE_NAN(GC::CANON_NAN_BITS | (STRING_TAG << GC::TAG_SHIFT) | 0x1230);
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| 
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|     u64 sign_bit = 1ULL << 63;
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| 
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|     EXPECT_TO_BE_NAN(GC::CANON_NAN_BITS | sign_bit | 0x1);
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|     EXPECT_TO_BE_NAN(GC::CANON_NAN_BITS | sign_bit | 0x10);
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|     EXPECT_TO_BE_NAN(GC::CANON_NAN_BITS | sign_bit | (NULL_TAG << GC::TAG_SHIFT));
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|     EXPECT_TO_BE_NAN(GC::CANON_NAN_BITS | sign_bit | (UNDEFINED_TAG << GC::TAG_SHIFT));
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|     EXPECT_TO_BE_NAN(GC::CANON_NAN_BITS | sign_bit | (INT32_TAG << GC::TAG_SHIFT) | 0x88);
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|     EXPECT_TO_BE_NAN(GC::CANON_NAN_BITS | sign_bit | (OBJECT_TAG << GC::TAG_SHIFT));
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|     EXPECT_TO_BE_NAN(GC::CANON_NAN_BITS | sign_bit | (OBJECT_TAG << GC::TAG_SHIFT) | 0x1230);
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|     EXPECT_TO_BE_NAN(GC::CANON_NAN_BITS | sign_bit | (STRING_TAG << GC::TAG_SHIFT));
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|     EXPECT_TO_BE_NAN(GC::CANON_NAN_BITS | sign_bit | (STRING_TAG << GC::TAG_SHIFT) | 0x1230);
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| 
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| #undef EXPECT_TO_BE_NAN
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| }
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