Changeset 221823 in webkit for trunk/Source/JavaScriptCore/assembler/ProbeStack.h

Timestamp:

Sep 9, 2017, 9:54:40 AM (8 years ago)

Author:

Ryan Haddad

Message:

Unreviewed, rolling out r221774.

This change introduced three debug JSC test timeouts.

Reverted changeset:

"Use JIT probes for DFG OSR exit."
​https://bugs.webkit.org/show_bug.cgi?id=175144
​http://trac.webkit.org/changeset/221774

File:

• trunk/Source/JavaScriptCore/assembler/ProbeStack.h (modified) (6 diffs)

trunk/Source/JavaScriptCore/assembler/ProbeStack.h

@@ -57 +57 @@
     T get(void* logicalAddress)
     {
-        void* from = physicalAddressFor(logicalAddress);
-        typename std::remove_const<T>::type to { };
-        std::memcpy(&to, from, sizeof(to)); // Use std::memcpy to avoid strict aliasing issues.
-        return to;
-    }
-    template<typename T>
-    T get(void* logicalBaseAddress, ptrdiff_t offset)
-    {
-        return get<T>(reinterpret_cast<uint8_t*>(logicalBaseAddress) + offset);
+        return *physicalAddressFor<T*>(logicalAddress);
     }
 
@@ -72 +64 @@
     {
         m_dirtyBits |= dirtyBitFor(logicalAddress);
-        void* to = physicalAddressFor(logicalAddress);
-        std::memcpy(to, &value, sizeof(T)); // Use std::memcpy to avoid strict aliasing issues.
-    }
-    template<typename T>
-    void set(void* logicalBaseAddress, ptrdiff_t offset, T value)
-    {
-        set<T>(reinterpret_cast<uint8_t*>(logicalBaseAddress) + offset, value);
+        *physicalAddressFor<T*>(logicalAddress) = value;
     }
 
@@ -95 +81 @@
     }
 
-    void* physicalAddressFor(void* logicalAddress)
+    template<typename T, typename = typename std::enable_if<std::is_pointer<T>::value>::type>
+    T physicalAddressFor(void* logicalAddress)
     {
-        return reinterpret_cast<uint8_t*>(logicalAddress) + m_physicalAddressOffset;
+        uintptr_t offset = reinterpret_cast<uintptr_t>(logicalAddress) & s_pageMask;
+        void* physicalAddress = reinterpret_cast<uint8_t*>(&m_buffer) + offset;
+        return reinterpret_cast<T>(physicalAddress);
     }
 
@@ -104 +93 @@
     void* m_baseLogicalAddress { nullptr };
     uintptr_t m_dirtyBits { 0 };
-    ptrdiff_t m_physicalAddressOffset;
 
     static constexpr size_t s_pageSize = 1024;
@@ -133 +121 @@
     Stack(Stack&& other);
 
-    void* lowWatermark()
-    {
-        // We use the chunkAddress for the low watermark because we'll be doing write backs
-        // to the stack in increments of chunks. Hence, we'll treat the lowest address of
-        // the chunk as the low watermark of any given set address.
-        return Page::chunkAddressFor(m_lowWatermark);
-    }
+    void* lowWatermark() { return m_lowWatermark; }
 
     template<typename T>
-    T get(void* address)
+    typename std::enable_if<!std::is_same<double, typename std::remove_cv<T>::type>::value, T>::type get(void* address)
     {
         Page* page = pageFor(address);
         return page->get<T>(address);
     }
-    template<typename T>
-    T get(void* logicalBaseAddress, ptrdiff_t offset)
-    {
-        return get<T>(reinterpret_cast<uint8_t*>(logicalBaseAddress) + offset);
-    }
 
-    template<typename T>
+    template<typename T, typename = typename std::enable_if<!std::is_same<double, typename std::remove_cv<T>::type>::value>::type>
     void set(void* address, T value)
     {
@@ -159 +136 @@
         page->set<T>(address, value);
 
-        if (address < m_lowWatermark)
-            m_lowWatermark = address;
+        // We use the chunkAddress for the low watermark because we'll be doing write backs
+        // to the stack in increments of chunks. Hence, we'll treat the lowest address of
+        // the chunk as the low watermark of any given set address.
+        void* chunkAddress = Page::chunkAddressFor(address);
+        if (chunkAddress < m_lowWatermark)
+            m_lowWatermark = chunkAddress;
     }
+
     template<typename T>
-    void set(void* logicalBaseAddress, ptrdiff_t offset, T value)
+    typename std::enable_if<std::is_same<double, typename std::remove_cv<T>::type>::value, T>::type get(void* address)
     {
-        set<T>(reinterpret_cast<uint8_t*>(logicalBaseAddress) + offset, value);
+        Page* page = pageFor(address);
+        return bitwise_cast<double>(page->get<uint64_t>(address));
+    }
+
+    template<typename T, typename = typename std::enable_if<std::is_same<double, typename std::remove_cv<T>::type>::value>::type>
+    void set(void* address, double value)
+    {
+        set<uint64_t>(address, bitwise_cast<uint64_t>(value));
     }