Bug#880693: mozjs52: Please add support for m68k

[John Paul Adrian Glaubitz]

Source: mozjs52
Version: 52.3.1-7
Severity: normal
Tags: patch
User: debian-68k at lists.debian.org
Usertags: m68k

Hi!

The attached patch adds support for m68k. It is based on
a number of patches that I submitted to Firefox upstream
but that unfortunately were never merged due to some
disagreement on how to resolve the alignment issues in a
compiler-agnostic way.

Since Debian uses either gcc or clang and not Microsoft's
C/C++ compiler, the patch shouldn't cause any issues since
the "__attribute__ ((aligned(4)))" is understood by both.

Note: This patch needs to be added on top of the patch for
      sh4 support in #880692 [2].

Additional patches for the remaining architectures will
follow shortly.

Thanks for consideration!

Adrian

> [1] https://bugzilla.mozilla.org/show_bug.cgi?id=1325771
> [2] https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=880692

--
 .''`.  John Paul Adrian Glaubitz
: :' :  Debian Developer - glaubitz at debian.org
`. `'   Freie Universitaet Berlin - glaubitz at physik.fu-berlin.de
  `-    GPG: 62FF 8A75 84E0 2956 9546  0006 7426 3B37 F5B5 F913
-------------- next part --------------
Description: Add support for m68k
 Based on the patches sent to Firefox upstream.
 See: https://bugzilla.mozilla.org/show_bug.cgi?id=1325771
 .
Author: John Paul Adrian Glaubitz <glaubitz at physik.fu-berlin.de>
Last-Update: 2017-11-03

Index: mozjs52-52.3.1/js/src/gc/Heap.h
===================================================================
--- mozjs52-52.3.1.orig/js/src/gc/Heap.h
+++ mozjs52-52.3.1/js/src/gc/Heap.h
@@ -282,7 +282,7 @@ struct Cell
   protected:
     inline uintptr_t address() const;
     inline Chunk* chunk() const;
-} JS_HAZ_GC_THING;
+} JS_HAZ_GC_THING __attribute__ ((aligned(4)));
 
 // A GC TenuredCell gets behaviors that are valid for things in the Tenured
 // heap, such as access to the arena and mark bits.
Index: mozjs52-52.3.1/js/src/jit/AtomicOperations.h
===================================================================
--- mozjs52-52.3.1.orig/js/src/jit/AtomicOperations.h
+++ mozjs52-52.3.1/js/src/jit/AtomicOperations.h
@@ -326,6 +326,8 @@ AtomicOperations::isLockfree(int32_t siz
 # include "jit/arm64/AtomicOperations-arm64.h"
 #elif defined(JS_CODEGEN_MIPS32) || defined(JS_CODEGEN_MIPS64)
 # include "jit/mips-shared/AtomicOperations-mips-shared.h"
+#elif defined(__m68k__)
+# include "jit/none/AtomicOperations-ppc.h"
 #elif defined(__ppc__) || defined(__PPC__)
 # include "jit/none/AtomicOperations-ppc.h"
 #elif defined(__sh__)
Index: mozjs52-52.3.1/js/src/jsfriendapi.h
===================================================================
--- mozjs52-52.3.1.orig/js/src/jsfriendapi.h
+++ mozjs52-52.3.1/js/src/jsfriendapi.h
@@ -571,7 +571,7 @@ public:
     uint32_t          slotInfo;
 
     static const uint32_t FIXED_SLOTS_SHIFT = 27;
-};
+} __attribute__ ((aligned(4)));
 
 /**
  * This layout is shared by all native objects. For non-native objects, the
Index: mozjs52-52.3.1/mfbt/double-conversion/utils.h
===================================================================
--- mozjs52-52.3.1.orig/mfbt/double-conversion/utils.h
+++ mozjs52-52.3.1/mfbt/double-conversion/utils.h
@@ -69,6 +69,8 @@
 #else
 #undef DOUBLE_CONVERSION_CORRECT_DOUBLE_OPERATIONS
 #endif  // _WIN32
+#elif defined(__m68k__)
+#undef DOUBLE_CONVERSION_CORRECT_DOUBLE_OPERATIONS
 #else
 #error Target architecture was not detected as supported by Double-Conversion.
 #endif
Index: mozjs52-52.3.1/mfbt/tests/TestPoisonArea.cpp
===================================================================
--- mozjs52-52.3.1.orig/mfbt/tests/TestPoisonArea.cpp
+++ mozjs52-52.3.1/mfbt/tests/TestPoisonArea.cpp
@@ -133,6 +133,9 @@
 #elif defined _ARCH_PPC || defined _ARCH_PWR || defined _ARCH_PWR2
 #define RETURN_INSTR 0x4E800020 /* blr */
 
+#elif defined __m68k__
+#define RETURN_INSTR 0x4E754E75 /* rts; rts */
+
 #elif defined __sparc || defined __sparcv9
 #define RETURN_INSTR 0x81c3e008 /* retl */
 
Index: mozjs52-52.3.1/python/mozbuild/mozbuild/configure/constants.py
===================================================================
--- mozjs52-52.3.1.orig/python/mozbuild/mozbuild/configure/constants.py
+++ mozjs52-52.3.1/python/mozbuild/mozbuild/configure/constants.py
@@ -44,6 +44,7 @@ CPU_bitness = {
     'arm': 32,
     'hppa': 32,
     'ia64': 64,
+    'm68k': 32,
     'mips32': 32,
     'mips64': 64,
     'ppc': 32,
@@ -87,6 +88,7 @@ CPU_preprocessor_checks = OrderedDict((
     ('mips64', '__mips64'),
     ('mips32', '__mips__'),
     ('sh4', '__sh__'),
+    ('m68k', '__m68k__'),
 ))
 
 assert sorted(CPU_preprocessor_checks.keys()) == sorted(CPU.POSSIBLE_VALUES)
Index: mozjs52-52.3.1/python/mozbuild/mozbuild/test/configure/test_toolchain_configure.py
===================================================================
--- mozjs52-52.3.1.orig/python/mozbuild/mozbuild/test/configure/test_toolchain_configure.py
+++ mozjs52-52.3.1/python/mozbuild/mozbuild/test/configure/test_toolchain_configure.py
@@ -1039,6 +1039,8 @@ class LinuxCrossCompileToolchainTest(Bas
         },
         'sh4-unknown-linux-gnu': little_endian + {
             '__sh__': 1,
+        'm68k-unknown-linux-gnu': big_endian + {
+            '__m68k__': 1,
         },
     }
 
Index: mozjs52-52.3.1/mfbt/tests/TestPair.cpp
===================================================================
--- mozjs52-52.3.1.orig/mfbt/tests/TestPair.cpp
+++ mozjs52-52.3.1/mfbt/tests/TestPair.cpp
@@ -29,14 +29,19 @@ using mozilla::Pair;
   static_assert(sizeof(name##_2) == (size), \
                 "Pair<" #T2 ", " #T1 "> has an unexpected size");
 
+static constexpr size_t sizemax(size_t a, size_t b)
+{
+  return (a > b) ? a : b;
+}
+
 INSTANTIATE(int, int, prim1, 2 * sizeof(int));
-INSTANTIATE(int, long, prim2, 2 * sizeof(long));
+INSTANTIATE(int, long, prim2, sizeof(long) + sizemax(sizeof(int), alignof(long)));
 
 struct EmptyClass { explicit EmptyClass(int) {} };
 struct NonEmpty { char mC; explicit NonEmpty(int) {} };
 
 INSTANTIATE(int, EmptyClass, both1, sizeof(int));
-INSTANTIATE(int, NonEmpty, both2, 2 * sizeof(int));
+INSTANTIATE(int, NonEmpty, both2, sizeof(int) + alignof(int));
 INSTANTIATE(EmptyClass, NonEmpty, both3, 1);
 
 struct A { char dummy; explicit A(int) {} };