* implement handmade aligned malloc, fast but always wastes 16 bytes of memory.

  only used as fallback for now, needs benchmarking.
  also notice that some malloc() impls do waste memory to keep track of alignment
  and other stuff (check msdn's page on malloc).
* expand test_dynalloc to cover low level aligned alloc funcs. Remove the old
  #ifdef EIGEN_VECTORIZE...
* rewrite the logic choosing an aligned alloc, some new stuff:
  * malloc() already aligned on freebsd and windows x64 (plus apple already)
  * _mm_malloc() used only if EIGEN_VECTORIZE
  * posix_memalign: correct detection according to man page (not necessarily
    linux specific), don't attempt to declare it if the platform didn't declare it
    (there had to be a reason why it didn't declare it, right?)

1 files changed, 54 insertions, 3 deletions

diff --git a/test/dynalloc.cpp b/test/dynalloc.cpp
index 916193df0..ffe21771a 100644
--- a/test/dynalloc.cpp
+++ b/test/dynalloc.cpp
@@ -24,6 +24,55 @@
 
 #include "main.h"
 
+void check_handmade_aligned_malloc()
+{
+  for(int i = 1; i < 1000; i++)
+  {
+    char *p = (char*)ei_handmade_aligned_malloc(i);
+    VERIFY(size_t(p)%16==0);
+    // if the buffer is wrongly allocated this will give a bad write --> check with valgrind
+    for(int j = 0; j < i; j++) p[j]=0;
+    ei_handmade_aligned_free(p);
+  }
+}
+
+void check_aligned_malloc()
+{
+  for(int i = 1; i < 1000; i++)
+  {
+    char *p = (char*)ei_aligned_malloc(i);
+    VERIFY(size_t(p)%16==0);
+    // if the buffer is wrongly allocated this will give a bad write --> check with valgrind
+    for(int j = 0; j < i; j++) p[j]=0;
+    ei_aligned_free(p);
+  }
+}
+
+void check_aligned_new()
+{
+  for(int i = 1; i < 1000; i++)
+  {
+    float *p = ei_aligned_new<float>(i);
+    VERIFY(size_t(p)%16==0);
+    // if the buffer is wrongly allocated this will give a bad write --> check with valgrind
+    for(int j = 0; j < i; j++) p[j]=0;
+    ei_aligned_delete(p,i);
+  }
+}
+
+void check_aligned_stack_alloc()
+{
+  for(int i = 1; i < 1000; i++)
+  {
+    float *p = ei_aligned_stack_new(float,i);
+    VERIFY(size_t(p)%16==0);
+    // if the buffer is wrongly allocated this will give a bad write --> check with valgrind
+    for(int j = 0; j < i; j++) p[j]=0;
+    ei_aligned_stack_delete(float,p,i);
+  }
+}
+
+
 // test compilation with both a struct and a class...
 struct MyStruct
 {
@@ -49,8 +98,12 @@ template<typename T> void check_dynaligned()
 
 void test_dynalloc()
 {
+  // low level dynamic memory allocation
+  CALL_SUBTEST(check_handmade_aligned_malloc());
+  CALL_SUBTEST(check_aligned_malloc());
+  CALL_SUBTEST(check_aligned_new());
+  CALL_SUBTEST(check_aligned_stack_alloc());
 
-#ifdef EIGEN_VECTORIZE
   for (int i=0; i<g_repeat*100; ++i)
   {
     CALL_SUBTEST( check_dynaligned<Vector4f>() );
@@ -100,6 +153,4 @@ void test_dynalloc()
     }
   }
   
-#endif // EIGEN_VECTORIZE
-
 }