Author: ikudrin
Date: Thu Sep 29 03:11:57 2016
New Revision: 282703

URL: http://llvm.org/viewvc/llvm-project?rev=282703&view=rev
Log:
Revert r282692: Use fallback_malloc to allocate __cxa_eh_globals in case of 
dynamic memory exhaustion.

The test breaks build bots.

Added:
    libcxxabi/trunk/src/fallback_malloc.ipp
      - copied unchanged from r282691, libcxxabi/trunk/src/fallback_malloc.ipp
Removed:
    libcxxabi/trunk/src/fallback_malloc.cpp
    libcxxabi/trunk/src/fallback_malloc.h
    libcxxabi/trunk/test/test_exception_storage_nodynmem.pass.cpp
Modified:
    libcxxabi/trunk/src/CMakeLists.txt
    libcxxabi/trunk/src/cxa_exception.cpp
    libcxxabi/trunk/src/cxa_exception_storage.cpp
    libcxxabi/trunk/test/test_fallback_malloc.pass.cpp

Modified: libcxxabi/trunk/src/CMakeLists.txt
URL: 
http://llvm.org/viewvc/llvm-project/libcxxabi/trunk/src/CMakeLists.txt?rev=282703&r1=282702&r2=282703&view=diff
==============================================================================
--- libcxxabi/trunk/src/CMakeLists.txt (original)
+++ libcxxabi/trunk/src/CMakeLists.txt Thu Sep 29 03:11:57 2016
@@ -12,7 +12,6 @@ set(LIBCXXABI_SOURCES
   cxa_vector.cpp
   cxa_virtual.cpp
   exception.cpp
-  fallback_malloc.cpp
   private_typeinfo.cpp
   stdexcept.cpp
   typeinfo.cpp

Modified: libcxxabi/trunk/src/cxa_exception.cpp
URL: 
http://llvm.org/viewvc/llvm-project/libcxxabi/trunk/src/cxa_exception.cpp?rev=282703&r1=282702&r2=282703&view=diff
==============================================================================
--- libcxxabi/trunk/src/cxa_exception.cpp (original)
+++ libcxxabi/trunk/src/cxa_exception.cpp Thu Sep 29 03:11:57 2016
@@ -15,10 +15,13 @@
 #include "cxxabi.h"
 
 #include <exception>        // for std::terminate
+#include <cstdlib>          // for malloc, free
 #include <cstring>          // for memset
+#ifndef _LIBCXXABI_HAS_NO_THREADS
+#  include <pthread.h>      // for fallback_malloc.ipp's mutexes
+#endif
 #include "cxa_exception.hpp"
 #include "cxa_handlers.hpp"
-#include "fallback_malloc.h"
 
 // +---------------------------+-----------------------------+---------------+
 // | __cxa_exception           | _Unwind_Exception CLNGC++\0 | thrown object |
@@ -101,6 +104,20 @@ static inline  int decrementHandlerCount
     return --exception->handlerCount;
 }
 
+#include "fallback_malloc.ipp"
+
+//  Allocate some memory from _somewhere_
+static void *do_malloc(size_t size) {
+    void *ptr = std::malloc(size);
+    if (NULL == ptr) // if malloc fails, fall back to emergency stash
+        ptr = fallback_malloc(size);
+    return ptr;
+}
+
+static void do_free(void *ptr) {
+    is_fallback_ptr(ptr) ? fallback_free(ptr) : std::free(ptr);
+}
+
 /*
     If reason isn't _URC_FOREIGN_EXCEPTION_CAUGHT, then the terminateHandler
     stored in exc is called.  Otherwise the exceptionDestructor stored in 
@@ -141,8 +158,7 @@ extern "C" {
 //  user's exception object.
 _LIBCXXABI_FUNC_VIS void *__cxa_allocate_exception(size_t thrown_size) throw() 
{
     size_t actual_size = 
cxa_exception_size_from_exception_thrown_size(thrown_size);
-    __cxa_exception *exception_header =
-        static_cast<__cxa_exception *>(__malloc_with_fallback(actual_size));
+    __cxa_exception* exception_header = 
static_cast<__cxa_exception*>(do_malloc(actual_size));
     if (NULL == exception_header)
         std::terminate();
     std::memset(exception_header, 0, actual_size);
@@ -152,7 +168,7 @@ _LIBCXXABI_FUNC_VIS void *__cxa_allocate
 
 //  Free a __cxa_exception object allocated with __cxa_allocate_exception.
 _LIBCXXABI_FUNC_VIS void __cxa_free_exception(void *thrown_object) throw() {
-    __free_with_fallback(cxa_exception_from_thrown_object(thrown_object));
+    do_free(cxa_exception_from_thrown_object(thrown_object));
 }
 
 
@@ -161,7 +177,7 @@ _LIBCXXABI_FUNC_VIS void __cxa_free_exce
 //  Otherwise, it will work like __cxa_allocate_exception.
 void * __cxa_allocate_dependent_exception () {
     size_t actual_size = sizeof(__cxa_dependent_exception);
-    void *ptr = __malloc_with_fallback(actual_size);
+    void *ptr = do_malloc(actual_size);
     if (NULL == ptr)
         std::terminate();
     std::memset(ptr, 0, actual_size);
@@ -172,7 +188,7 @@ void * __cxa_allocate_dependent_exceptio
 //  This function shall free a dependent_exception.
 //  It does not affect the reference count of the primary exception.
 void __cxa_free_dependent_exception (void * dependent_exception) {
-    __free_with_fallback(dependent_exception);
+    do_free(dependent_exception);
 }
 
 

Modified: libcxxabi/trunk/src/cxa_exception_storage.cpp
URL: 
http://llvm.org/viewvc/llvm-project/libcxxabi/trunk/src/cxa_exception_storage.cpp?rev=282703&r1=282702&r2=282703&view=diff
==============================================================================
--- libcxxabi/trunk/src/cxa_exception_storage.cpp (original)
+++ libcxxabi/trunk/src/cxa_exception_storage.cpp Thu Sep 29 03:11:57 2016
@@ -45,8 +45,8 @@ extern "C" {
 #else
 
 #include <pthread.h>
+#include <cstdlib>          // for calloc, free
 #include "abort_message.h"
-#include "fallback_malloc.h"
 
 //  In general, we treat all pthread errors as fatal.
 //  We cannot call std::terminate() because that will in turn
@@ -58,7 +58,7 @@ namespace {
     pthread_once_t flag_ = PTHREAD_ONCE_INIT;
 
     void destruct_ (void *p) {
-        __free_with_fallback ( p );
+        std::free ( p );
         if ( 0 != ::pthread_setspecific ( key_, NULL ) ) 
             abort_message("cannot zero out thread value for 
__cxa_get_globals()");
         }
@@ -77,7 +77,7 @@ extern "C" {
     //  If this is the first time we've been asked for these globals, create 
them
         if ( NULL == retVal ) {
             retVal = static_cast<__cxa_eh_globals*>
-                        (__calloc_with_fallback (1, sizeof 
(__cxa_eh_globals)));
+                        (std::calloc (1, sizeof (__cxa_eh_globals)));
             if ( NULL == retVal )
                 abort_message("cannot allocate __cxa_eh_globals");
             if ( 0 != pthread_setspecific ( key_, retVal ) )

Removed: libcxxabi/trunk/src/fallback_malloc.cpp
URL: 
http://llvm.org/viewvc/llvm-project/libcxxabi/trunk/src/fallback_malloc.cpp?rev=282702&view=auto
==============================================================================
--- libcxxabi/trunk/src/fallback_malloc.cpp (original)
+++ libcxxabi/trunk/src/fallback_malloc.cpp (removed)
@@ -1,226 +0,0 @@
-//===------------------------ fallback_malloc.cpp 
-------------------------===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-
-#include "fallback_malloc.h"
-
-#include "config.h"
-
-#include <cstdlib> // for malloc, calloc, free
-#include <cstring> // for memset
-
-#ifndef _LIBCXXABI_HAS_NO_THREADS
-#include <pthread.h> // for mutexes
-#endif
-
-//  A small, simple heap manager based (loosely) on
-//  the startup heap manager from FreeBSD, optimized for space.
-//
-//  Manages a fixed-size memory pool, supports malloc and free only.
-//  No support for realloc.
-//
-//  Allocates chunks in multiples of four bytes, with a four byte header
-//  for each chunk. The overhead of each chunk is kept low by keeping pointers
-//  as two byte offsets within the heap, rather than (4 or 8 byte) pointers.
-
-namespace {
-
-// When POSIX threads are not available, make the mutex operations a nop
-#ifndef _LIBCXXABI_HAS_NO_THREADS
-static pthread_mutex_t heap_mutex = PTHREAD_MUTEX_INITIALIZER;
-#else
-static void * heap_mutex = 0;
-#endif
-
-class mutexor {
-public:
-#ifndef _LIBCXXABI_HAS_NO_THREADS
-    mutexor ( pthread_mutex_t *m ) : mtx_(m) { pthread_mutex_lock ( mtx_ ); }
-    ~mutexor () { pthread_mutex_unlock ( mtx_ ); }
-#else
-    mutexor ( void * ) {}
-    ~mutexor () {}
-#endif
-private:
-    mutexor ( const mutexor &rhs );
-    mutexor & operator = ( const mutexor &rhs );
-#ifndef _LIBCXXABI_HAS_NO_THREADS
-    pthread_mutex_t *mtx_;
-#endif
-    };
-
-
-static const size_t HEAP_SIZE = 512;
-char heap [ HEAP_SIZE ] __attribute__((aligned));
-
-typedef unsigned short heap_offset;
-typedef unsigned short heap_size;
-
-struct heap_node {
-    heap_offset next_node;  // offset into heap
-    heap_size   len;        // size in units of "sizeof(heap_node)"
-};
-
-static const heap_node *list_end = (heap_node *) ( &heap [ HEAP_SIZE ] );   // 
one past the end of the heap
-static heap_node *freelist = NULL;
-
-heap_node *node_from_offset ( const heap_offset offset )
-    { return (heap_node *) ( heap + ( offset * sizeof (heap_node))); }
-
-heap_offset offset_from_node ( const heap_node *ptr )
-    { return 
static_cast<heap_offset>(static_cast<size_t>(reinterpret_cast<const char 
*>(ptr) - heap)  / sizeof (heap_node)); }
-
-void init_heap () {
-    freelist = (heap_node *) heap;
-    freelist->next_node = offset_from_node ( list_end );
-    freelist->len = HEAP_SIZE / sizeof (heap_node);
-    }
-
-//  How big a chunk we allocate
-size_t alloc_size (size_t len)
-    { return (len + sizeof(heap_node) - 1) / sizeof(heap_node) + 1; }
-
-bool is_fallback_ptr ( void *ptr )
-    { return ptr >= heap && ptr < ( heap + HEAP_SIZE ); }
-
-void *fallback_malloc(size_t len) {
-    heap_node *p, *prev;
-    const size_t nelems = alloc_size ( len );
-    mutexor mtx ( &heap_mutex );
-
-    if ( NULL == freelist )
-        init_heap ();
-
-//  Walk the free list, looking for a "big enough" chunk
-    for (p = freelist, prev = 0;
-            p && p != list_end;     prev = p, p = node_from_offset ( 
p->next_node)) {
-
-        if (p->len > nelems) {  //  chunk is larger, shorten, and return the 
tail
-            heap_node *q;
-
-            p->len = static_cast<heap_size>(p->len - nelems);
-            q = p + p->len;
-            q->next_node = 0;
-            q->len = static_cast<heap_size>(nelems);
-            return (void *) (q + 1);
-        }
-
-        if (p->len == nelems) { // exact size match
-            if (prev == 0)
-                freelist = node_from_offset(p->next_node);
-            else
-                prev->next_node = p->next_node;
-            p->next_node = 0;
-            return (void *) (p + 1);
-        }
-    }
-    return NULL;    // couldn't find a spot big enough
-}
-
-//  Return the start of the next block
-heap_node *after ( struct heap_node *p ) { return p + p->len; }
-
-void fallback_free (void *ptr) {
-    struct heap_node *cp = ((struct heap_node *) ptr) - 1;      // retrieve 
the chunk
-    struct heap_node *p, *prev;
-
-    mutexor mtx ( &heap_mutex );
-
-#ifdef DEBUG_FALLBACK_MALLOC
-        std::cout << "Freeing item at " << offset_from_node ( cp ) << " of 
size " << cp->len << std::endl;
-#endif
-
-    for (p = freelist, prev = 0;
-            p && p != list_end;     prev = p, p = node_from_offset 
(p->next_node)) {
-#ifdef DEBUG_FALLBACK_MALLOC
-        std::cout << "  p, cp, after (p), after(cp) "
-            << offset_from_node ( p ) << ' '
-            << offset_from_node ( cp ) << ' '
-            << offset_from_node ( after ( p )) << ' '
-            << offset_from_node ( after ( cp )) << std::endl;
-#endif
-        if ( after ( p ) == cp ) {
-#ifdef DEBUG_FALLBACK_MALLOC
-            std::cout << "  Appending onto chunk at " << offset_from_node ( p 
) << std::endl;
-#endif
-            p->len = static_cast<heap_size>(p->len + cp->len);  // make the 
free heap_node larger
-            return;
-            }
-        else if ( after ( cp ) == p ) { // there's a free heap_node right after
-#ifdef DEBUG_FALLBACK_MALLOC
-            std::cout << "  Appending free chunk at " << offset_from_node ( p 
) << std::endl;
-#endif
-            cp->len = static_cast<heap_size>(cp->len + p->len);
-            if ( prev == 0 ) {
-                freelist = cp;
-                cp->next_node = p->next_node;
-                }
-            else
-                prev->next_node = offset_from_node(cp);
-            return;
-            }
-        }
-//  Nothing to merge with, add it to the start of the free list
-#ifdef DEBUG_FALLBACK_MALLOC
-            std::cout << "  Making new free list entry " << offset_from_node ( 
cp ) << std::endl;
-#endif
-    cp->next_node = offset_from_node ( freelist );
-    freelist = cp;
-}
-
-#ifdef INSTRUMENT_FALLBACK_MALLOC
-size_t print_free_list () {
-    struct heap_node *p, *prev;
-    heap_size total_free = 0;
-    if ( NULL == freelist )
-        init_heap ();
-
-    for (p = freelist, prev = 0;
-            p && p != list_end;     prev = p, p = node_from_offset 
(p->next_node)) {
-        std::cout << ( prev == 0 ? "" : "  ")  << "Offset: " << 
offset_from_node ( p )
-                << "\tsize: " << p->len << " Next: " << p->next_node << 
std::endl;
-        total_free += p->len;
-        }
-    std::cout << "Total Free space: " << total_free << std::endl;
-    return total_free;
-    }
-#endif
-}  // end unnamed namespace
-
-namespace __cxxabiv1 {
-
-#pragma GCC visibility push(hidden)
-
-void * __malloc_with_fallback(size_t size) {
-    void *ptr = std::malloc(size);
-    if (NULL == ptr) // if malloc fails, fall back to emergency stash
-        ptr = fallback_malloc(size);
-    return ptr;
-}
-
-void * __calloc_with_fallback(size_t count, size_t size) {
-    void *ptr = std::calloc(count, size);
-    if (NULL != ptr)
-        return ptr;
-    // if calloc fails, fall back to emergency stash
-    ptr = fallback_malloc(size * count);
-    if (NULL != ptr)
-        std::memset(ptr, 0, size * count);
-    return ptr;
-}
-
-void __free_with_fallback(void *ptr) {
-    if (is_fallback_ptr(ptr))
-        fallback_free(ptr);
-    else
-        std::free(ptr);
-}
-
-#pragma GCC visibility pop
-
-} // namespace __cxxabiv1

Removed: libcxxabi/trunk/src/fallback_malloc.h
URL: 
http://llvm.org/viewvc/llvm-project/libcxxabi/trunk/src/fallback_malloc.h?rev=282702&view=auto
==============================================================================
--- libcxxabi/trunk/src/fallback_malloc.h (original)
+++ libcxxabi/trunk/src/fallback_malloc.h (removed)
@@ -1,31 +0,0 @@
-//===------------------------- fallback_malloc.h 
--------------------------===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-
-#ifndef _FALLBACK_MALLOC_H
-#define _FALLBACK_MALLOC_H
-
-#include <cstddef> // for size_t
-
-namespace __cxxabiv1 {
-
-#pragma GCC visibility push(hidden)
-
-// Allocate some memory from _somewhere_
-void * __malloc_with_fallback(size_t size);
-
-// Allocate and zero-initialize memory from _somewhere_
-void * __calloc_with_fallback(size_t count, size_t size);
-
-void __free_with_fallback(void *ptr);
-
-#pragma GCC visibility pop
-
-} // namespace __cxxabiv1
-
-#endif

Removed: libcxxabi/trunk/test/test_exception_storage_nodynmem.pass.cpp
URL: 
http://llvm.org/viewvc/llvm-project/libcxxabi/trunk/test/test_exception_storage_nodynmem.pass.cpp?rev=282702&view=auto
==============================================================================
--- libcxxabi/trunk/test/test_exception_storage_nodynmem.pass.cpp (original)
+++ libcxxabi/trunk/test/test_exception_storage_nodynmem.pass.cpp (removed)
@@ -1,32 +0,0 @@
-//===--------------- test_exception_storage_nodynmem.cpp 
------------------===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-
-#include <assert.h>
-#include <cstdlib>
-
-static bool OverwrittenCallocCalled = false;
-
-// Override calloc to simulate exhaustion of dynamic memory
-void *calloc(size_t, size_t) {
-    OverwrittenCallocCalled = true;
-    return 0;
-}
-
-int main(int argc, char *argv[]) {
-    // Run the test a couple of times
-    // to ensure that fallback memory doesn't leak.
-    for (int I = 0; I < 1000; ++I)
-        try {
-            throw 42;
-        } catch (...) {
-        }
-
-    assert(OverwrittenCallocCalled);
-    return 0;
-}

Modified: libcxxabi/trunk/test/test_fallback_malloc.pass.cpp
URL: 
http://llvm.org/viewvc/llvm-project/libcxxabi/trunk/test/test_fallback_malloc.pass.cpp?rev=282703&r1=282702&r2=282703&view=diff
==============================================================================
--- libcxxabi/trunk/test/test_fallback_malloc.pass.cpp (original)
+++ libcxxabi/trunk/test/test_fallback_malloc.pass.cpp Thu Sep 29 03:11:57 2016
@@ -16,7 +16,7 @@ typedef std::deque<void *> container;
 
 // #define  DEBUG_FALLBACK_MALLOC
 #define INSTRUMENT_FALLBACK_MALLOC
-#include "../src/fallback_malloc.cpp"
+#include "../src/fallback_malloc.ipp"
 
 container alloc_series ( size_t sz ) {
     container ptrs;


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