Changeset 253010 in webkit

Timestamp:

Dec 2, 2019 2:45:25 PM (4 years ago)

Author:

Tadeu Zagallo

Message:

[JSC] Remove BytecodeCacheVersion.h
​https://bugs.webkit.org/show_bug.cgi?id=204760

Reviewed by Mark Lam.

Having that as a phony make target causes a lot of unnecessary rebuilds. That was a workaround
the fact that we only need a new cache version when we rebuild CachedTypes.cpp, but there was
no straightforward way to get the current timestamp as an integer at that point. Instead, we now
just use a constexpr function that hashes TIMESTAMP.

• CMakeLists.txt:
• DerivedSources-output.xcfilelist:
• DerivedSources.make:
• runtime/CachedTypes.cpp:

(JSC::jscBytecodeCacheVersion):
(JSC::GenericCacheEntry::isUpToDate const):

Location:

trunk/Source/JavaScriptCore

Files:

• CMakeLists.txt (modified) (1 diff)
• ChangeLog (modified) (1 diff)
• DerivedSources-output.xcfilelist (modified) (1 diff)
• DerivedSources.make (modified) (1 diff)
• runtime/CachedTypes.cpp (modified) (4 diffs)

trunk/Source/JavaScriptCore/CMakeLists.txt

@@ -226 +226 @@
 endif ()
 
-file(WRITE ${JavaScriptCore_DERIVED_SOURCES_DIR}/BytecodeCacheVersion.h "#define JSC_BYTECODE_CACHE_VERSION ${BUILD_TIME}\n")
-
 list(APPEND JavaScriptCore_HEADERS
-    ${JavaScriptCore_DERIVED_SOURCES_DIR}/BytecodeCacheVersion.h
     ${JavaScriptCore_DERIVED_SOURCES_DIR}/BytecodeStructs.h
     ${JavaScriptCore_DERIVED_SOURCES_DIR}/Bytecodes.h

trunk/Source/JavaScriptCore/ChangeLog

@@ +1 @@
+2019-12-02  Tadeu Zagallo  <tzagallo@apple.com>
+
+        [JSC] Remove BytecodeCacheVersion.h
+        https://bugs.webkit.org/show_bug.cgi?id=204760
+
+        Reviewed by Mark Lam.
+
+        Having that as a phony make target causes a lot of unnecessary rebuilds. That was a workaround
+        the fact that we only need a new cache version when we rebuild CachedTypes.cpp, but there was
+        no straightforward way to get the current timestamp as an integer at that point. Instead, we now
+        just use a constexpr function that hashes __TIMESTAMP__.
+
+        * CMakeLists.txt:
+        * DerivedSources-output.xcfilelist:
+        * DerivedSources.make:
+        * runtime/CachedTypes.cpp:
+        (JSC::jscBytecodeCacheVersion):
+        (JSC::GenericCacheEntry::isUpToDate const):
+
 2019-12-02  Mark Lam  <mark.lam@apple.com>
 

trunk/Source/JavaScriptCore/DerivedSources-output.xcfilelist

@@ -9 +9 @@
 $(BUILT_PRODUCTS_DIR)/DerivedSources/JavaScriptCore/BigIntPrototype.lut.h
 $(BUILT_PRODUCTS_DIR)/DerivedSources/JavaScriptCore/BooleanPrototype.lut.h
-$(BUILT_PRODUCTS_DIR)/DerivedSources/JavaScriptCore/BytecodeCacheVersion.h
 $(BUILT_PRODUCTS_DIR)/DerivedSources/JavaScriptCore/BytecodeIndices.h
 $(BUILT_PRODUCTS_DIR)/DerivedSources/JavaScriptCore/BytecodeStructs.h

trunk/Source/JavaScriptCore/DerivedSources.make

@@ -364 +364 @@
     $(OBJECT_LUT_HEADERS) \
 #
-
-.PHONY : BytecodeCacheVersion.h
-
-BytecodeCacheVersion.h:
-        echo "#define JSC_BYTECODE_CACHE_VERSION $(shell date '+%s')" > BytecodeCacheVersion.h
-
-all : BytecodeCacheVersion.h

trunk/Source/JavaScriptCore/runtime/CachedTypes.cpp

@@ -28 +28 @@
 
 #include "BytecodeCacheError.h"
-#include "BytecodeCacheVersion.h"
 #include "BytecodeLivenessAnalysis.h"
 #include "JSCInlines.h"
@@ -65 +64 @@
 template<typename T>
 using SourceType = typename SourceTypeImpl<T>::type;
+
+static constexpr unsigned jscBytecodeCacheVersion()
+{
+    return StringHasher::computeHash(__TIMESTAMP__);
+}
 
 class Encoder {
@@ -2266 +2270 @@
     bool isUpToDate(Decoder& decoder) const
     {
-        if (m_cacheVersion != JSC_BYTECODE_CACHE_VERSION)
+        if (m_cacheVersion != jscBytecodeCacheVersion())
             return false;
         if (m_bootSessionUUID.decode(decoder) != bootSessionUUIDString())
@@ -2274 +2278 @@
 
 private:
-    uint32_t m_cacheVersion { JSC_BYTECODE_CACHE_VERSION };
+    uint32_t m_cacheVersion { jscBytecodeCacheVersion() };
     CachedString m_bootSessionUUID;
     CachedCodeBlockTag m_tag;