Changeset 172863 in webkit

Timestamp:

Aug 22, 2014 11:59:49 AM (10 years ago)

Author:

commit-queue@webkit.org

Message:

Enable fixed executable allocator for any ARM64 target.
​https://bugs.webkit.org/show_bug.cgi?id=136162

Patch by Akos Kiss <​akiss@inf.u-szeged.hu> on 2014-08-22
Reviewed by Michael Saboff.

The ARM64 macro assembler relies on near calls being implemented by BL
instructions, which have only 128MB offset range from PC. The
on-demand executable allocator cannot ensure that any two locations in
memory allocated for the JIT-compiled code are within this range.
However, the fixed executable allocator has a fixed 16MB memory pool for
ARM64.

• wtf/Platform.h:

Define ENABLE_EXECUTABLE_ALLOCATOR_FIXED if CPU(ARM64), and update
attached comment.

Location:

trunk/Source/WTF

Files:

• ChangeLog (modified) (1 diff)
• wtf/Platform.h (modified) (1 diff)

trunk/Source/WTF/ChangeLog

@@ +1 @@
+2014-08-22  Akos Kiss  <akiss@inf.u-szeged.hu>
+
+        Enable fixed executable allocator for any ARM64 target.
+        https://bugs.webkit.org/show_bug.cgi?id=136162
+
+        Reviewed by Michael Saboff.
+
+        The ARM64 macro assembler relies on near calls being implemented by BL
+        instructions, which have only 128MB offset range from PC. The
+        on-demand executable allocator cannot ensure that any two locations in
+        memory allocated for the JIT-compiled code are within this range. 
+        However, the fixed executable allocator has a fixed 16MB memory pool for
+        ARM64.
+
+        * wtf/Platform.h:
+        Define ENABLE_EXECUTABLE_ALLOCATOR_FIXED if CPU(ARM64), and update
+        attached comment.
+
 2014-08-22  Commit Queue  <commit-queue@webkit.org>
 

trunk/Source/WTF/wtf/Platform.h

@@ -821 +821 @@
 
 /* Pick which allocator to use; we only need an executable allocator if the assembler is compiled in.
-   On x86-64 we use a single fixed mmap, on other platforms we mmap on demand. */
+   On non-Windows x86-64, iOS, and ARM64 we use a single fixed mmap, on other platforms we mmap on demand. */
 #if ENABLE(ASSEMBLER)
-#if CPU(X86_64) && !OS(WINDOWS) || PLATFORM(IOS)
+#if CPU(X86_64) && !OS(WINDOWS) || PLATFORM(IOS) || CPU(ARM64)
 #define ENABLE_EXECUTABLE_ALLOCATOR_FIXED 1
 #else