[test-suite] Bitcode simd tests: align memory to 128.

[asbirlea]

Summary

Patch preparing the addition of more tests.
Some require 128 alignment, so update driver to allocate aligned memory.

[asbirlea]

I tested the change on Linux and OSX.
Suggestions on if there are other architecture specific changes I missed are welcome.

[mehdi_amini]

Bitcode/simd_ops/simd_ops.cpp

19

Will this work on Windows?

[asbirlea]

Bitcode/simd_ops/simd_ops.cpp

19

I looked it up and I think I need to use "_aligned_malloc()".
Looking for ways to test it, I don't have one handy.

[echristo]

Bitcode/simd_ops/simd_ops.cpp

19

For portability there's nothing specific that will work across everything until C++17. _aligned_malloc is the right way for windows.

Perhaps abstract it out into an aligned allocation function. Also, if you wouldn't mind commenting this routine as well as to why we're allocating aligned memory :)

[asbirlea]

Update for Windows. Merge options for OSX/Linux.

[asbirlea]

Add comment.

[echristo]

One inline comment :)

Bitcode/simd_ops/simd_ops.cpp

6

Comment what's going on here and why we're allocating memory if you wouldn't mind? It might be nicer for this to be a function rather than a macro? Just call it alloc_aligned or something and have the functionality for all 3 platforms in there?

[asbirlea]

Address comment.

[asbirlea]

Bitcode/simd_ops/simd_ops.cpp

6

Moved the comment from below here and created a function instead of the macro.
There are just two cases, since I can unify OSX and Linux with the posix method.

[echristo]

good enough. Thanks!

LGTM.

-eric

Bitcode/simd_ops/halide_buffer.h

 #include <stdlib.h>
 #include <stdio.h>
 #include <time.h>
+#if !defined(__APPLE__)
+#include <malloc.h>
+#endif
 #ifndef HALIDE_ATTRIBUTE_ALIGN
   #ifdef _MSC_VER
     #define HALIDE_ATTRIBUTE_ALIGN(x) __declspec(align(x))
   #else
     #define HALIDE_ATTRIBUTE_ALIGN(x) __attribute__((aligned(x)))
   #endif
 #endif
 #ifndef BUFFER_T_DEFINED

Bitcode/simd_ops/simd_ops.cpp

 #include "filter_test_op.h"
 
 template<typename T>
 T rand_value() {
     return (T)(rand() * 0.125) - 100;
 }
 
 // Even on android, we want errors to stdout
 extern "C" void halide_print(void *, const char *msg) {
     printf("%s\n", msg);
 }
 
 template<typename T>
 buffer_t make_buffer(int w, int h) {
-    T *mem = new T[w*h];
+#if defined(__APPLE__)
+    T *mem;
+    int err = posix_memalign((void **)&mem, 128, w*h*sizeof(T));
+#else
+    T *mem = (T *)memalign(128, w*h*sizeof(T));
+#endif
     buffer_t buf = {0};
     buf.host = (uint8_t *)mem;
     buf.extent[0] = w;
     buf.extent[1] = h;
     buf.elem_size = sizeof(T);
     buf.stride[0] = 1;
     buf.stride[1] = w;