BLD: Move numpy.build_utils -> numpy._build_utils, add to MANIFEST.in

This fixes the distutils built from an sdist (e.g. under tox),
without including _build_utils in binary distributions or the installed numpy.

1 files changed, 227 insertions, 0 deletions

diff --git a/numpy/_build_utils/src/apple_sgemv_fix.c b/numpy/_build_utils/src/apple_sgemv_fix.c
new file mode 100644
index 000000000..ffdfb81f7
--- /dev/null
+++ b/numpy/_build_utils/src/apple_sgemv_fix.c
@@ -0,0 +1,227 @@
+/* This is a collection of ugly hacks to circumvent a bug in
+ * Apple Accelerate framework's SGEMV subroutine.
+ *
+ * See: https://github.com/numpy/numpy/issues/4007
+ *
+ * SGEMV in Accelerate framework will segfault on MacOS X version 10.9
+ * (aka Mavericks) if arrays are not aligned to 32 byte boundaries
+ * and the CPU supports AVX instructions. This can produce segfaults
+ * in np.dot.
+ *
+ * This patch overshadows the symbols cblas_sgemv, sgemv_ and sgemv
+ * exported by Accelerate to produce the correct behavior. The MacOS X
+ * version and CPU specs are checked on module import. If Mavericks and
+ * AVX are detected the call to SGEMV is emulated with a call to SGEMM
+ * if the arrays are not 32 byte aligned. If the exported symbols cannot
+ * be overshadowed on module import, a fatal error is produced and the
+ * process aborts. All the fixes are in a self-contained C file
+ * and do not alter the multiarray C code. The patch is not applied
+ * unless NumPy is configured to link with Apple's Accelerate
+ * framework.
+ *
+ */
+
+#define NPY_NO_DEPRECATED_API NPY_API_VERSION
+#include "Python.h"
+#include "numpy/arrayobject.h"
+
+#include <string.h>
+#include <dlfcn.h>
+#include <stdlib.h>
+#include <stdio.h>
+
+/* ----------------------------------------------------------------- */
+/* Original cblas_sgemv */
+
+#define VECLIB_FILE "/System/Library/Frameworks/Accelerate.framework/Versions/A/Frameworks/vecLib.framework/vecLib"
+
+enum CBLAS_ORDER {CblasRowMajor=101, CblasColMajor=102};
+enum CBLAS_TRANSPOSE {CblasNoTrans=111, CblasTrans=112, CblasConjTrans=113};
+extern void cblas_xerbla(int info, const char *rout, const char *form, ...);
+
+typedef void cblas_sgemv_t(const enum CBLAS_ORDER order,
+                 const enum CBLAS_TRANSPOSE TransA, const int M, const int N,
+                 const float alpha, const float  *A, const int lda,
+                 const float  *X, const int incX,
+                 const float beta, float  *Y, const int incY);
+
+typedef void cblas_sgemm_t(const enum CBLAS_ORDER order,
+                 const enum CBLAS_TRANSPOSE TransA, const enum CBLAS_TRANSPOSE TransB,
+                 const int M, const int N, const int K,
+                 const float alpha, const float  *A, const int lda,
+                 const float  *B, const int ldb,
+                 const float beta, float  *C, const int incC);
+
+typedef void fortran_sgemv_t( const char* trans, const int* m, const int* n,
+             const float* alpha, const float* A, const int* ldA,
+             const float* X, const int* incX,
+             const float* beta, float* Y, const int* incY );
+
+static void *veclib = NULL;
+static cblas_sgemv_t *accelerate_cblas_sgemv = NULL;
+static cblas_sgemm_t *accelerate_cblas_sgemm = NULL;
+static fortran_sgemv_t *accelerate_sgemv = NULL;
+static int AVX_and_10_9 = 0;
+
+/* Dynamic check for AVX support
+ * __builtin_cpu_supports("avx") is available in gcc 4.8,
+ * but clang and icc do not currently support it. */
+#define cpu_supports_avx()\
+(system("sysctl -n machdep.cpu.features | grep -q AVX") == 0)
+
+/* Check if we are using MacOS X version 10.9 */
+#define using_mavericks()\
+(system("sw_vers -productVersion | grep -q 10\\.9\\.") == 0)
+
+__attribute__((destructor))
+static void unloadlib(void)
+{
+   if (veclib) dlclose(veclib);
+}
+
+__attribute__((constructor))
+static void loadlib()
+/* automatically executed on module import */
+{
+    char errormsg[1024];
+    int AVX, MAVERICKS;
+    memset((void*)errormsg, 0, sizeof(errormsg));
+    /* check if the CPU supports AVX */
+    AVX = cpu_supports_avx();
+    /* check if the OS is MacOS X Mavericks */
+    MAVERICKS = using_mavericks();
+    /* we need the workaround when the CPU supports
+     * AVX and the OS version is Mavericks */
+    AVX_and_10_9 = AVX && MAVERICKS;
+    /* load vecLib */
+    veclib = dlopen(VECLIB_FILE, RTLD_LOCAL | RTLD_FIRST);
+    if (!veclib) {
+        veclib = NULL;
+        snprintf(errormsg, sizeof(errormsg),
+                 "Failed to open vecLib from location '%s'.", VECLIB_FILE);
+        Py_FatalError(errormsg); /* calls abort() and dumps core */
+    }
+    /* resolve Fortran SGEMV from Accelerate */
+    accelerate_sgemv = (fortran_sgemv_t*) dlsym(veclib, "sgemv_");
+    if (!accelerate_sgemv) {
+        unloadlib();
+        Py_FatalError("Failed to resolve symbol 'sgemv_'.");
+    }
+    /* resolve cblas_sgemv from Accelerate */
+    accelerate_cblas_sgemv = (cblas_sgemv_t*) dlsym(veclib, "cblas_sgemv");
+    if (!accelerate_cblas_sgemv) {
+        unloadlib();
+        Py_FatalError("Failed to resolve symbol 'cblas_sgemv'.");
+    }
+    /* resolve cblas_sgemm from Accelerate */
+    accelerate_cblas_sgemm = (cblas_sgemm_t*) dlsym(veclib, "cblas_sgemm");
+    if (!accelerate_cblas_sgemm) {
+        unloadlib();
+        Py_FatalError("Failed to resolve symbol 'cblas_sgemm'.");
+    }
+}
+
+/* ----------------------------------------------------------------- */
+/* Fortran SGEMV override */
+
+void sgemv_( const char* trans, const int* m, const int* n,
+             const float* alpha, const float* A, const int* ldA,
+             const float* X, const int* incX,
+             const float* beta, float* Y, const int* incY )
+{
+    /* It is safe to use the original SGEMV if we are not using AVX on Mavericks
+     * or the input arrays A, X and Y are all aligned on 32 byte boundaries. */
+    #define BADARRAY(x) (((npy_intp)(void*)x) % 32)
+    const int use_sgemm = AVX_and_10_9 && (BADARRAY(A) || BADARRAY(X) || BADARRAY(Y));
+    if (!use_sgemm) {
+        accelerate_sgemv(trans,m,n,alpha,A,ldA,X,incX,beta,Y,incY);
+        return;
+    }
+
+    /* Arrays are misaligned, the CPU supports AVX, and we are running
+     * Mavericks.
+     *
+     * Emulation of SGEMV with SGEMM:
+     *
+     * SGEMV allows vectors to be strided. SGEMM requires all arrays to be
+     * contiguous along the leading dimension. To emulate striding in SGEMV
+     * with the leading dimension arguments in SGEMM we compute
+     *
+     *    Y = alpha * op(A) @ X + beta * Y
+     *
+     * as
+     *
+     *    Y.T = alpha * X.T @ op(A).T + beta * Y.T
+     *
+     * Because Fortran uses column major order and X.T and Y.T are row vectors,
+     * the leading dimensions of X.T and Y.T in SGEMM become equal to the
+     * strides of the the column vectors X and Y in SGEMV. */
+
+    switch (*trans) {
+        case 'T':
+        case 't':
+        case 'C':
+        case 'c':
+            accelerate_cblas_sgemm( CblasColMajor, CblasNoTrans, CblasNoTrans,
+                1, *n, *m, *alpha, X, *incX, A, *ldA, *beta, Y, *incY );
+            break;
+        case 'N':
+        case 'n':
+            accelerate_cblas_sgemm( CblasColMajor, CblasNoTrans, CblasTrans,
+                1, *m, *n, *alpha, X, *incX, A, *ldA, *beta, Y, *incY );
+            break;
+        default:
+            cblas_xerbla(1, "SGEMV", "Illegal transpose setting: %c\n", *trans);
+    }
+}
+
+/* ----------------------------------------------------------------- */
+/* Override for an alias symbol for sgemv_ in Accelerate */
+
+void sgemv (char *trans,
+            const int *m, const int *n,
+            const float *alpha,
+            const float *A, const int *lda,
+            const float *B, const int *incB,
+            const float *beta,
+            float *C, const int *incC)
+{
+    sgemv_(trans,m,n,alpha,A,lda,B,incB,beta,C,incC);
+}
+
+/* ----------------------------------------------------------------- */
+/* cblas_sgemv override, based on Netlib CBLAS code */
+
+void cblas_sgemv(const enum CBLAS_ORDER order,
+                 const enum CBLAS_TRANSPOSE TransA, const int M, const int N,
+                 const float alpha, const float  *A, const int lda,
+                 const float  *X, const int incX, const float beta,
+                 float  *Y, const int incY)
+{
+   char TA;
+   if (order == CblasColMajor)
+   {
+      if (TransA == CblasNoTrans) TA = 'N';
+      else if (TransA == CblasTrans) TA = 'T';
+      else if (TransA == CblasConjTrans) TA = 'C';
+      else
+      {
+         cblas_xerbla(2, "cblas_sgemv","Illegal TransA setting, %d\n", TransA);
+      }
+      sgemv_(&TA, &M, &N, &alpha, A, &lda, X, &incX, &beta, Y, &incY);
+   }
+   else if (order == CblasRowMajor)
+   {
+      if (TransA == CblasNoTrans) TA = 'T';
+      else if (TransA == CblasTrans) TA = 'N';
+      else if (TransA == CblasConjTrans) TA = 'N';
+      else
+      {
+         cblas_xerbla(2, "cblas_sgemv", "Illegal TransA setting, %d\n", TransA);
+         return;
+      }
+      sgemv_(&TA, &N, &M, &alpha, A, &lda, X, &incX, &beta, Y, &incY);
+   }
+   else
+      cblas_xerbla(1, "cblas_sgemv", "Illegal Order setting, %d\n", order);
+}