kEight = 8
#endif
-#if defined(OBJC_COLLECTING_CACHE)
// _objc_entryPoints and _objc_exitPoints are used by objc
// to get the critical regions for which method caches
// cannot be garbage collected.
.data
.globl _objc_entryPoints
_objc_entryPoints:
+ .long __cache_getImp
+ .long __cache_getMethod
.long _objc_msgSend
.long _objc_msgSend_stret
.long _objc_msgSendSuper
.globl _objc_exitPoints
_objc_exitPoints:
+ .long LGetImpExit
+ .long LGetMethodExit
.long LMsgSendExit
.long LMsgSendStretExit
.long LMsgSendSuperExit
.long LMsgSendSuperStretExit
.long 0
-#endif
/********************************************************************
/////////////////////////////////////////////////////////////////////
//
//
-// CacheLookup WORD_RETURN | STRUCT_RETURN, MSG_SEND | MSG_SENDSUPER, cacheMissLabel
+// CacheLookup WORD_RETURN | STRUCT_RETURN, MSG_SEND | MSG_SENDSUPER | CACHE_GET, cacheMissLabel
//
// Locate the implementation for a selector in a class method cache.
//
// Takes: WORD_RETURN (first parameter is at sp+4)
// STRUCT_RETURN (struct address is at sp+4, first parameter at sp+8)
-// MSG_SEND (first parameter is receiver)
+// MSG_SEND (first parameter is receiver)
// MSG_SENDSUPER (first parameter is address of objc_super structure)
+// CACHE_GET (first parameter is class; return method triplet)
//
// cacheMissLabel = label to branch to iff method is not cached
//
-// On exit: (found) imp in eax register
+// On exit: (found) MSG_SEND and MSG_SENDSUPER: return imp in eax
+// (found) CACHE_GET: return method triplet in eax
// (not found) jumps to cacheMissLabel
//
/////////////////////////////////////////////////////////////////////
// Values to specify to method lookup macros whether the first argument
// is an object/class reference or a 'objc_super' structure.
-MSG_SEND = 0
-MSG_SENDSUPER = 1
+MSG_SEND = 0 // first argument is receiver, search the isa
+MSG_SENDSUPER = 1 // first argument is objc_super, search the class
+CACHE_GET = 2 // first argument is class, search that class
.macro CacheLookup
.if $1 == MSG_SEND // MSG_SEND
movl isa(%eax), %eax // class = self->isa
movl selector(%esp), %ecx // get selector
-.else // MSG_SENDSUPER
+.elseif $1 == MSG_SENDSUPER // MSG_SENDSUPER
movl super(%esp), %eax // get objc_super address
movl class(%eax), %eax // class = caller->class
movl selector(%esp), %ecx // get selector
+.else // CACHE_GET
+ movl selector(%esp), %ecx // get selector - class already in eax
.endif
.else // Struct return
.if $1 == MSG_SEND // MSG_SEND (stret)
movl isa(%eax), %eax // class = self->isa
movl (selector_stret)(%esp), %ecx // get selector
-.else // MSG_SENDSUPER (stret)
+.elseif $1 == MSG_SENDSUPER // MSG_SENDSUPER (stret)
movl super_stret(%esp), %eax // get objc_super address
movl class(%eax), %eax // class = caller->class
movl (selector_stret)(%esp), %ecx // get selector
+.else // CACHE_GET
+ !! This should not happen.
.endif
.endif
leal buckets(%eax), %edi // buckets = &cache->buckets
movl mask(%eax), %esi // mask = cache->mask
movl %ecx, %edx // index = selector
+#ifdef NO_MACRO_CONSTS
+ shrl $kTwo, %edx // index = selector >> 2
+#else
+ shrl $2, %edx // index = selector >> 2
+#endif
// search the receiver's cache
-LMsgSendProbeCache_$0_$1:
+LMsgSendProbeCache_$0_$1_$2:
#if defined(OBJC_INSTRUMENTED)
inc %ebx // probeCount += 1
#endif
movl (%edi, %edx, 4), %eax // method = buckets[index]
testl %eax, %eax // check for end of bucket
- je LMsgSendCacheMiss_$0_$1 // go to cache miss code
+ je LMsgSendCacheMiss_$0_$1_$2 // go to cache miss code
cmpl method_name(%eax), %ecx // check for method name match
- je LMsgSendCacheHit_$0_$1 // go handle cache hit
+ je LMsgSendCacheHit_$0_$1_$2 // go handle cache hit
inc %edx // bump index ...
- jmp LMsgSendProbeCache_$0_$1// ... and loop
+ jmp LMsgSendProbeCache_$0_$1_$2 // ... and loop
// not found in cache: restore state and go to callers handler
-LMsgSendCacheMiss_$0_$1:
+LMsgSendCacheMiss_$0_$1_$2:
#if defined(OBJC_INSTRUMENTED)
popl %edx // retrieve cache pointer
movl mask(%edx), %esi // mask = cache->mask
testl %esi, %esi // a mask of zero is only for the...
- je LMsgSendMissInstrumentDone_$0 // ... emptyCache, do not record anything
+ je LMsgSendMissInstrumentDone_$0_$1_$2 // ... emptyCache, do not record anything
// locate and update the CacheInstrumentation structure
inc %esi // entryCount = mask + 1
movl %edi, missProbes(%esi) // cacheData->missProbes += probeCount
movl maxMissProbes(%esi), %edi// if (cacheData->maxMissProbes < probeCount)
cmpl %ebx, %edi //
- jge LMsgSendMaxMissProbeOK_$0 //
+ jge LMsgSendMaxMissProbeOK_$0_$1_$2 //
movl %ebx, maxMissProbes(%esi)// cacheData->maxMissProbes = probeCount
-LMsgSendMaxMissProbeOK_$0:
+LMsgSendMaxMissProbeOK_$0_$1_$2:
// update cache miss probe histogram
cmpl $CACHE_HISTOGRAM_SIZE, %ebx // pin probeCount to max index
- jl LMsgSendMissHistoIndexSet_$0
+ jl LMsgSendMissHistoIndexSet_$0_$1_$2
movl $(CACHE_HISTOGRAM_SIZE-1), %ebx
-LMsgSendMissHistoIndexSet_$0:
+LMsgSendMissHistoIndexSet_$0_$1_$2:
LEA_STATIC_DATA %esi, _CacheMissHistogram, EXTERNAL_SYMBOL
#ifdef NO_MACRO_CONSTS
shll $kTwo, %ebx // convert probeCount to histogram index
movl 0(%esi), %edi // get current tally
inc %edi //
movl %edi, 0(%esi) // tally += 1
-LMsgSendMissInstrumentDone_$0:
+LMsgSendMissInstrumentDone_$0_$1_$2:
popl %ebx // restore non-volatile register
#endif
.if $1 == MSG_SEND // MSG_SEND
popl %esi // restore callers register
popl %edi // restore callers register
- movl self(%esp), %eax // get messaged object
+ movl self(%esp), %eax // get messaged object
movl isa(%eax), %eax // get objects class
-.else // MSG_SENDSUPER
+.elseif $1 == MSG_SENDSUPER // MSG_SENDSUPER
// replace "super" arg with "receiver"
movl super+8(%esp), %edi // get super structure
movl receiver(%edi), %esi // get messaged object
movl class(%edi), %eax // get messaged class
popl %esi // restore callers register
popl %edi // restore callers register
+.else // CACHE_GET
+ popl %esi // restore callers register
+ popl %edi // restore callers register
.endif
.else // Struct return
.if $1 == MSG_SEND // MSG_SEND (stret)
popl %edi // restore callers register
movl self_stret(%esp), %eax // get messaged object
movl isa(%eax), %eax // get objects class
-.else // MSG_SENDSUPER (stret)
+.elseif $1 == MSG_SENDSUPER // MSG_SENDSUPER (stret)
// replace "super" arg with "receiver"
movl super_stret+8(%esp), %edi// get super structure
movl receiver(%edi), %esi // get messaged object
movl class(%edi), %eax // get messaged class
popl %esi // restore callers register
popl %edi // restore callers register
+.else // CACHE_GET
+ !! This should not happen.
.endif
.endif
// eax points to matching cache entry
.align 4, 0x90
-LMsgSendCacheHit_$0_$1:
+LMsgSendCacheHit_$0_$1_$2:
#if defined(OBJC_INSTRUMENTED)
popl %edx // retrieve cache pointer
movl mask(%edx), %esi // mask = cache->mask
testl %esi, %esi // a mask of zero is only for the...
- je LMsgSendHitInstrumentDone_$0_$1 // ... emptyCache, do not record anything
+ je LMsgSendHitInstrumentDone_$0_$1_$2 // ... emptyCache, do not record anything
// locate and update the CacheInstrumentation structure
inc %esi // entryCount = mask + 1
movl %edi, hitProbes(%esi) // cacheData->hitProbes += probeCount
movl maxHitProbes(%esi), %edi// if (cacheData->maxHitProbes < probeCount)
cmpl %ebx, %edi
- jge LMsgSendMaxHitProbeOK_$0_$1
+ jge LMsgSendMaxHitProbeOK_$0_$1_$2
movl %ebx, maxHitProbes(%esi)// cacheData->maxHitProbes = probeCount
-LMsgSendMaxHitProbeOK_$0_$1:
+LMsgSendMaxHitProbeOK_$0_$1_$2:
// update cache hit probe histogram
cmpl $CACHE_HISTOGRAM_SIZE, %ebx // pin probeCount to max index
- jl LMsgSendHitHistoIndexSet_$0_$1
+ jl LMsgSendHitHistoIndexSet_$0_$1_$2
movl $(CACHE_HISTOGRAM_SIZE-1), %ebx
-LMsgSendHitHistoIndexSet_$0_$1:
+LMsgSendHitHistoIndexSet_$0_$1_$2:
LEA_STATIC_DATA %esi, _CacheHitHistogram, EXTERNAL_SYMBOL
#ifdef NO_MACRO_CONSTS
shll $kTwo, %ebx // convert probeCount to histogram index
movl 0(%esi), %edi // get current tally
inc %edi //
movl %edi, 0(%esi) // tally += 1
-LMsgSendHitInstrumentDone_$0_$1:
+LMsgSendHitInstrumentDone_$0_$1_$2:
popl %ebx // restore non-volatile register
#endif
// load implementation address, restore state, and we're done
+.if $1 == CACHE_GET
+ // method triplet is already in eax
+.else
movl method_imp(%eax), %eax // imp = method->method_imp
+.endif
.if $0 == WORD_RETURN // Regular word return
.if $1 == MSG_SENDSUPER // MSG_SENDSUPER
PICIFY(func) ; \
jmp %edx ;
+
+
+
+/********************************************************************
+ * Method _cache_getMethod(Class cls, SEL sel)
+ *
+ * If found, returns method triplet pointer.
+ * If not found, returns NULL.
+ *
+ * NOTE: _cache_getMethod never returns any cache entry whose implementation
+ * is _objc_msgForward. It returns NULL instead. This prevents thread-
+ * safety and memory management bugs in _class_lookupMethodAndLoadCache.
+ * See _class_lookupMethodAndLoadCache for details.
+ ********************************************************************/
+
+ ENTRY __cache_getMethod
+
+// load the class into eax
+ movl self(%esp), %eax
+
+// do lookup
+ CacheLookup WORD_RETURN, CACHE_GET, LGetMethodMiss
+
+// cache hit, method triplet in %eax
+// check for _objc_msgForward
+ LEA_STATIC_DATA %ecx, __objc_msgForward, LOCAL_SYMBOL // eats edx
+ cmpl method_imp(%eax), %ecx
+ je LGetMethodMiss // if (imp==_objc_msgForward) return nil
+ ret // else return method triplet address
+
+LGetMethodMiss:
+// cache miss, return nil
+ xorl %eax, %eax // zero %eax
+ ret
+
+LGetMethodExit:
+ END_ENTRY __cache_getMethod
+
+
+/********************************************************************
+ * IMP _cache_getImp(Class cls, SEL sel)
+ *
+ * If found, returns method implementation.
+ * If not found, returns NULL.
+ ********************************************************************/
+
+ ENTRY __cache_getImp
+
+// load the class into eax
+ movl self(%esp), %eax
+
+// do lookup
+ CacheLookup WORD_RETURN, CACHE_GET, LGetImpMiss
+
+// cache hit, method triplet in %eax
+ movl method_imp(%eax), %eax // return method imp
+ ret
+
+LGetImpMiss:
+// cache miss, return nil
+ xorl %eax, %eax // zero %eax
+ ret
+
+LGetImpExit:
+ END_ENTRY __cache_getImp
+
+
/********************************************************************
*
* id objc_msgSend(id self, SEL _cmd,...);
testl %eax, %eax
je LMsgSendNilSelf
-#if !defined(OBJC_COLLECTING_CACHE)
-// check whether context is multithreaded
- EXTERN_TO_REG(__objc_multithread_mask,%ecx)
- testl %ecx, %ecx
- je LMsgSendMT
-#endif
-
-// single threaded and receiver is non-nil: search the cache
+// receiver is non-nil: search the cache
CacheLookup WORD_RETURN, MSG_SEND, LMsgSendCacheMiss
movl $kFwdMsgSend, %edx // flag word-return for _objc_msgForward
jmp *%eax // goto *imp
movl $kFwdMsgSend, %edx // flag word-return for _objc_msgForward
jmp *%eax // goto *imp
-#if !defined(OBJC_COLLECTING_CACHE)
-// multithreaded: hold _messageLock while accessing cache
-LMsgSendMT:
- movl $1, %ecx // acquire _messageLock
- LEA_STATIC_DATA %eax, _messageLock, EXTERNAL_SYMBOL
-LMsgSendLockSpin:
- xchgl %ecx, (%eax)
- cmpl $0, %ecx
- jne LMsgSendLockSpin
- movl self(%esp), %eax // restore eax
-
- CacheLookup WORD_RETURN, MSG_SEND, LMsgSendMTCacheMiss
- LEA_STATIC_DATA %ecx, _messageLock, EXTERNAL_SYMBOL
- movl $0, (%ecx) // unlock
- movl $kFwdMsgSend, %edx // flag word-return for _objc_msgForward
- jmp *%eax // goto *imp
-
-// cache miss: go search the method lists
-LMsgSendMTCacheMiss:
- MethodTableLookup WORD_RETURN, MSG_SEND
- LEA_STATIC_DATA %ecx, _messageLock, EXTERNAL_SYMBOL
- movl $0, (%ecx) // unlock
- movl $kFwdMsgSend, %edx // flag word-return for _objc_msgForward
- jmp *%eax // goto *imp
-#endif
-
// message sent to nil object: call optional handler and return nil
LMsgSendNilSelf:
EXTERN_TO_REG(__objc_msgNil,%eax)
movl super(%esp), %eax
-#if !defined(OBJC_COLLECTING_CACHE)
-// check whether context is multithreaded
- EXTERN_TO_REG_AGAIN(__objc_multithread_mask,%ecx)
- testl %ecx, %ecx
- je LMsgSendSuperMT
-#endif
-
-// single threaded and receiver is non-nil: search the cache
+// receiver is non-nil: search the cache
CacheLookup WORD_RETURN, MSG_SENDSUPER, LMsgSendSuperCacheMiss
movl $kFwdMsgSend, %edx // flag word-return for _objc_msgForward
jmp *%eax // goto *imp
movl $kFwdMsgSend, %edx // flag word-return for _objc_msgForward
jmp *%eax // goto *imp
-#if !defined(OBJC_COLLECTING_CACHE)
-LMsgSendSuperMT:
-// multithreaded: hold _messageLock while accessing cache
- movl $1, %ecx // acquire _messageLock
- LEA_STATIC_DATA %eax, _messageLock, EXTERNAL_SYMBOL
-LMsgSendSuperLockSpin:
- xchgl %ecx, (%eax)
- cmpl $0, %ecx
- jne LMsgSendSuperLockSpin
- movl super(%esp), %eax // restore eax
-
- CacheLookup WORD_RETURN, MSG_SENDSUPER, LMsgSendSuperMTCacheMiss
- LEA_STATIC_DATA %ecx, _messageLock, EXTERNAL_SYMBOL
- movl $0, (%ecx) // unlock
- movl $kFwdMsgSend, %edx // flag word-return for _objc_msgForward
- jmp *%eax // goto *imp
-
-// cache miss: go search the method lists
-LMsgSendSuperMTCacheMiss:
- MethodTableLookup WORD_RETURN, MSG_SENDSUPER
- LEA_STATIC_DATA %ecx, _messageLock, EXTERNAL_SYMBOL
- movl $0, (%ecx) // unlock
- movl $kFwdMsgSend, %edx // flag word-return for _objc_msgForward
- jmp *%eax // goto *imp
-#endif
-
LMsgSendSuperExit:
END_ENTRY _objc_msgSendSuper
testl %eax, %eax
je LMsgSendStretNilSelf
-#if !defined(OBJC_COLLECTING_CACHE)
-// check whether context is multithreaded
- EXTERN_TO_REG_AGAIN(__objc_multithread_mask,%ecx)
- testl %ecx, %ecx
- je LMsgSendStretMT
-#endif
-
-// single threaded and receiver is non-nil: search the cache
+// receiver is non-nil: search the cache
CacheLookup STRUCT_RETURN, MSG_SEND, LMsgSendStretCacheMiss
movl $kFwdMsgSendStret, %edx // flag struct-return for _objc_msgForward
jmp *%eax // goto *imp
movl $kFwdMsgSendStret, %edx // flag struct-return for _objc_msgForward
jmp *%eax // goto *imp
-#if !defined(OBJC_COLLECTING_CACHE)
-// multithreaded: hold _messageLock while accessing cache
-LMsgSendStretMT:
- movl $1, %ecx // acquire _messageLock
- LEA_STATIC_DATA %eax, _messageLock, EXTERNAL_SYMBOL
-LMsgSendStretLockSpin:
- xchgl %ecx, (%eax)
- cmpl $0, %ecx
- jne LMsgSendStretLockSpin
- movl self_stret(%esp), %eax // restore eax
-
- CacheLookup STRUCT_RETURN, MSG_SEND, LMsgSendStretMTCacheMiss
- LEA_STATIC_DATA %ecx, _messageLock, EXTERNAL_SYMBOL
- movl $0, (%ecx) // unlock
- movl $kFwdMsgSendStret, %edx // flag struct-return for _objc_msgForward
- jmp *%eax // goto *imp
-
-// cache miss: go search the method lists
-LMsgSendStretMTCacheMiss:
- MethodTableLookup STRUCT_RETURN, MSG_SEND
- LEA_STATIC_DATA %ecx, _messageLock, EXTERNAL_SYMBOL
- movl $0, (%ecx) // unlock
- movl $kFwdMsgSendStret, %edx // flag struct-return for _objc_msgForward
- jmp *%eax // goto *imp
-#endif
-
// message sent to nil object: call optional handler and return nil
LMsgSendStretNilSelf:
EXTERN_TO_REG_AGAIN(__objc_msgNil,%eax)
movl super_stret(%esp), %eax
-#if !defined(OBJC_COLLECTING_CACHE)
-// check whether context is multithreaded
- EXTERN_TO_REG_AGAIN(__objc_multithread_mask,%ecx)
- testl %ecx, %ecx
- je LMsgSendSuperStretMT
-#endif
-
-// single threaded and receiver is non-nil: search the cache
+// receiver is non-nil: search the cache
CacheLookup STRUCT_RETURN, MSG_SENDSUPER, LMsgSendSuperStretCacheMiss
movl $kFwdMsgSendStret, %edx // flag struct-return for _objc_msgForward
jmp *%eax // goto *imp
movl $kFwdMsgSendStret, %edx // flag struct-return for _objc_msgForward
jmp *%eax // goto *imp
-#if !defined(OBJC_COLLECTING_CACHE)
-LMsgSendStretSuperMT:
-// multithreaded: hold _messageLock while accessing cache
- movl $1, %ecx // acquire _messageLock
- LEA_STATIC_DATA %eax, _messageLock, EXTERNAL_SYMBOL
-LMsgSendSuperStretLockSpin:
- xchgl %ecx, (%eax)
- cmpl $0, %ecx
- jne LMsgSendSuperStretLockSpin
- movl super_stret(%esp), %eax // restore eax
-
- CacheLookup STRUCT_RETURN, MSG_SENDSUPER, LMsgSendSuperStretMTCacheMiss
- LEA_STATIC_DATA %ecx, _messageLock, EXTERNAL_SYMBOL
- movl $0, (%ecx) // unlock
- movl $kFwdMsgSendStret, %edx // flag struct-return for _objc_msgForward
- jmp *%eax // goto *imp
-
-// cache miss: go search the method lists
-LMsgSendSuperStretMTCacheMiss:
- MethodTableLookup MSG_SENDSUPER
- LEA_STATIC_DATA %ecx, _messageLock, EXTERNAL_SYMBOL
- movl $0, (%ecx) // unlock
- movl $kFwdMsgSendStret, %edx // flag struct-return for _objc_msgForward
- jmp *%eax // goto *imp
-#endif
-
LMsgSendSuperStretExit:
END_ENTRY _objc_msgSendSuper_stret
#endif
pushl %ecx
pushl (self_stret+16)(%esp)
- call _objc_msgSend_stret
+ call _objc_msgSend
movl %ebp,%esp
popl %ebp
ret
projects / apple / objc4.git / blobdiff