Changeset 239364 in webkit

Timestamp:

Dec 18, 2018, 6:27:00 PM (8 years ago)

Author:

sbarati@apple.com

Message:

Update ARM64EHash
​https://bugs.webkit.org/show_bug.cgi?id=192823
<rdar://problem/45468257>

Reviewed by Mark Lam.

• assembler/ARM64Assembler.h:

(JSC::ARM64Assembler::ARM64Assembler):

• assembler/AbstractMacroAssembler.h:

(JSC::AbstractMacroAssembler::AbstractMacroAssembler):

• assembler/AssemblerBuffer.h:

(JSC::ARM64EHash::update):
(JSC::ARM64EHash::finalHash const):
(JSC::AssemblerBuffer::AssemblerBuffer):
(JSC::AssemblerBuffer::putIntegralUnchecked):
(JSC::ARM64EHash::ARM64EHash): Deleted.
(JSC::ARM64EHash::hash const): Deleted.
(JSC::ARM64EHash::randomSeed const): Deleted.

• assembler/LinkBuffer.cpp:

(JSC::LinkBuffer::copyCompactAndLinkCode):

Location:

trunk/Source/JavaScriptCore

Files:

• ChangeLog (modified) (1 diff)
• assembler/ARM64Assembler.h (modified) (1 diff)
• assembler/AbstractMacroAssembler.h (modified) (1 diff)
• assembler/AssemblerBuffer.h (modified) (3 diffs)
• assembler/LinkBuffer.cpp (modified) (4 diffs)

trunk/Source/JavaScriptCore/ChangeLog

@@ +1 @@
+2018-12-18  Saam Barati  <sbarati@apple.com>
+
+        Update ARM64EHash
+        https://bugs.webkit.org/show_bug.cgi?id=192823
+        <rdar://problem/45468257>
+
+        Reviewed by Mark Lam.
+
+        * assembler/ARM64Assembler.h:
+        (JSC::ARM64Assembler::ARM64Assembler):
+        * assembler/AbstractMacroAssembler.h:
+        (JSC::AbstractMacroAssembler::AbstractMacroAssembler):
+        * assembler/AssemblerBuffer.h:
+        (JSC::ARM64EHash::update):
+        (JSC::ARM64EHash::finalHash const):
+        (JSC::AssemblerBuffer::AssemblerBuffer):
+        (JSC::AssemblerBuffer::putIntegralUnchecked):
+        (JSC::ARM64EHash::ARM64EHash): Deleted.
+        (JSC::ARM64EHash::hash const): Deleted.
+        (JSC::ARM64EHash::randomSeed const): Deleted.
+        * assembler/LinkBuffer.cpp:
+        (JSC::LinkBuffer::copyCompactAndLinkCode):
+
 2018-12-18  Mark Lam  <mark.lam@apple.com>
 

trunk/Source/JavaScriptCore/assembler/ARM64Assembler.h

@@ -327 +327 @@
 
 public:
-    ARM64Assembler(
-#if CPU(ARM64E)
-        unsigned randomNumber
-#endif 
-        )
+    ARM64Assembler()
         : m_indexOfLastWatchpoint(INT_MIN)
         , m_indexOfTailOfLastWatchpoint(INT_MIN)
-#if CPU(ARM64E)
-        , m_buffer(randomNumber)
-#endif
-        
     {
     }

trunk/Source/JavaScriptCore/assembler/AbstractMacroAssembler.h

@@ -987 +987 @@
     AbstractMacroAssembler()
         : m_randomSource(0)
-#if CPU(ARM64E)
-        , m_assembler(random())
-#else
         , m_assembler()
-#endif
     {
         invalidateAllTempRegisters();

trunk/Source/JavaScriptCore/assembler/AssemblerBuffer.h

@@ -150 +150 @@
     class ARM64EHash {
     public:
-        ARM64EHash(unsigned randomNumber)
-            : m_hash(randomNumber)
-            , m_randomSeed(randomNumber)
-        { }
-        ALWAYS_INLINE void update(unsigned value, uintptr_t index)
-        {
-            m_hash = tagInt((static_cast<uintptr_t>(value) + m_hash) ^ (m_hash >> 32), static_cast<PtrTag>(index));
-        }
-        uintptr_t hash() const { return m_hash; }
-        unsigned randomSeed() const { return m_randomSeed; }
+        ARM64EHash() = default;
+        ALWAYS_INLINE void update(uint32_t value)
+        {
+            uint64_t input = value ^ m_hash;
+            uint64_t a = static_cast<uint32_t>(tagInt(input, static_cast<PtrTag>(0)) >> 39);
+            uint64_t b = tagInt(input, static_cast<PtrTag>(0xb7e151628aed2a6a)) >> 23;
+            m_hash = a | b;
+        }
+        uint32_t finalHash() const
+        {
+            uint64_t hash = m_hash;
+            uint64_t a = static_cast<uint32_t>(tagInt(hash, static_cast<PtrTag>(0xbf7158809cf4f3c7)) >> 39);
+            uint64_t b = tagInt(hash, static_cast<PtrTag>(0x62e7160f38b4da56)) >> 23;
+            return static_cast<uint32_t>(a | b);
+        }
     private:
-        uintptr_t m_hash;
-        unsigned m_randomSeed;
+        uint32_t m_hash { 0 };
     };
 #endif
@@ -168 +172 @@
     class AssemblerBuffer {
     public:
-        AssemblerBuffer(
-#if CPU(ARM64E)
-            unsigned randomNumber
-#endif
-        )
+        AssemblerBuffer()
             : m_storage()
             , m_index(0)
-#if CPU(ARM64E)
-            , m_hash(randomNumber)
-#endif
         {
         }
@@ -310 +307 @@
             static_assert(sizeof(value) == 4, "");
 #if CPU(ARM64E)
-            m_hash.update(value, m_index);
+            m_hash.update(value);
 #endif
 #endif

trunk/Source/JavaScriptCore/assembler/LinkBuffer.cpp

@@ -140 +140 @@
     uint8_t* codeOutData = m_code.dataLocation<uint8_t*>();
 #if CPU(ARM64E) && ENABLE(FAST_JIT_PERMISSIONS)
-    const ARM64EHash assemblerBufferHash = macroAssembler.m_assembler.buffer().hash();
-    ARM64EHash verifyUncompactedHash(assemblerBufferHash.randomSeed());
+    const uint32_t expectedFinalHash = macroAssembler.m_assembler.buffer().hash().finalHash();
+    ARM64EHash verifyUncompactedHash;
     uint8_t* outData = codeOutData;
 #if ENABLE(SEPARATED_WX_HEAP)
@@ -179 +179 @@
             ASSERT(!(readPtr % 2));
             ASSERT(!(writePtr % 2));
-#if CPU(ARM64E) && ENABLE(FAST_JIT_PERMISSIONS)
-            unsigned index = readPtr;
-#endif
             while (copySource != copyEnd) {
                 InstructionType insn = *copySource++;
 #if CPU(ARM64E) && ENABLE(FAST_JIT_PERMISSIONS)
                 static_assert(sizeof(InstructionType) == 4, "");
-                verifyUncompactedHash.update(insn, index);
-                index += sizeof(InstructionType);
+                verifyUncompactedHash.update(insn);
 #endif
                 *copyDst++ = insn;
@@ -232 +228 @@
         RELEASE_ASSERT(bytes % sizeof(InstructionType) == 0);
 
-#if CPU(ARM64E) && ENABLE(FAST_JIT_PERMISSIONS)
-        unsigned index = readPtr;
-#endif
-
         for (size_t i = 0; i < bytes; i += sizeof(InstructionType)) {
             InstructionType insn = *src++;
 #if CPU(ARM64E) && ENABLE(FAST_JIT_PERMISSIONS)
-            verifyUncompactedHash.update(insn, index);
-            index += sizeof(InstructionType);
+            verifyUncompactedHash.update(insn);
 #endif
             *dst++ = insn;
@@ -247 +238 @@
 
 #if CPU(ARM64E) && ENABLE(FAST_JIT_PERMISSIONS)
-    if (verifyUncompactedHash.hash() != assemblerBufferHash.hash()) {
-        dataLogLn("Hashes don't match: ", RawPointer(bitwise_cast<void*>(verifyUncompactedHash.hash())), " ", RawPointer(bitwise_cast<void*>(assemblerBufferHash.hash())));
+    if (verifyUncompactedHash.finalHash() != expectedFinalHash) {
+        dataLogLn("Hashes don't match: ", RawPointer(bitwise_cast<void*>(static_cast<uintptr_t>(verifyUncompactedHash.finalHash()))), " ", RawPointer(bitwise_cast<void*>(static_cast<uintptr_t>(expectedFinalHash))));
         dataLogLn("Crashing!");
         CRASH();