malloc: solve dead code issue in memalign()

[people/ms/u-boot.git] / common / dlmalloc.c

diff --git a/common/dlmalloc.c b/common/dlmalloc.c
index 6453ee9c259fcde7bfbe63099255b9823d5580c2..5ea37dfb6e4c334db262b6726bfff0e1d5362508 100644 (file)
--- a/common/dlmalloc.c
+++ b/common/dlmalloc.c
@@ -1535,9 +1535,9 @@ void mem_malloc_init(ulong start, ulong size)
 
        debug("using memory %#lx-%#lx for malloc()\n", mem_malloc_start,
              mem_malloc_end);
-
-       memset((void *)mem_malloc_start, 0, size);
-
+#ifdef CONFIG_SYS_MALLOC_CLEAR_ON_INIT
+       memset((void *)mem_malloc_start, 0x0, size);
+#endif
        malloc_bin_reloc();
 }
 
@@ -2829,6 +2829,28 @@ Void_t* mEMALIGn(alignment, bytes) size_t alignment; size_t bytes;
   nb = request2size(bytes);
   m  = (char*)(mALLOc(nb + alignment + MINSIZE));
 
+  /*
+  * The attempt to over-allocate (with a size large enough to guarantee the
+  * ability to find an aligned region within allocated memory) failed.
+  *
+  * Try again, this time only allocating exactly the size the user wants. If
+  * the allocation now succeeds and just happens to be aligned, we can still
+  * fulfill the user's request.
+  */
+  if (m == NULL) {
+    /*
+     * Use bytes not nb, since mALLOc internally calls request2size too, and
+     * each call increases the size to allocate, to account for the header.
+     */
+    m  = (char*)(mALLOc(bytes));
+    /* Aligned -> return it */
+    if ((((unsigned long)(m)) % alignment) == 0)
+      return m;
+    /* Otherwise, fail */
+    fREe(m);
+    m = NULL;
+  }
+
   if (m == NULL) return NULL; /* propagate failure */
 
   p = mem2chunk(m);
@@ -2948,9 +2970,11 @@ Void_t* cALLOc(n, elem_size) size_t n; size_t elem_size;
 
 
   /* check if expand_top called, in which case don't need to clear */
+#ifdef CONFIG_SYS_MALLOC_CLEAR_ON_INIT
 #if MORECORE_CLEARS
   mchunkptr oldtop = top;
   INTERNAL_SIZE_T oldtopsize = chunksize(top);
+#endif
 #endif
   Void_t* mem = mALLOc (sz);
 
@@ -2977,12 +3001,14 @@ Void_t* cALLOc(n, elem_size) size_t n; size_t elem_size;
 
     csz = chunksize(p);
 
+#ifdef CONFIG_SYS_MALLOC_CLEAR_ON_INIT
 #if MORECORE_CLEARS
     if (p == oldtop && csz > oldtopsize)
     {
       /* clear only the bytes from non-freshly-sbrked memory */
       csz = oldtopsize;
     }
+#endif
 #endif
 
     MALLOC_ZERO(mem, csz - SIZE_SZ);
@@ -3257,6 +3283,17 @@ int mALLOPt(param_number, value) int param_number; int value;
   }
 }
 
+int initf_malloc(void)
+{
+#ifdef CONFIG_SYS_MALLOC_F_LEN
+       assert(gd->malloc_base);        /* Set up by crt0.S */
+       gd->malloc_limit = CONFIG_SYS_MALLOC_F_LEN;
+       gd->malloc_ptr = 0;
+#endif
+
+       return 0;
+}
+
 /*
 
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