BUILD: Remove Accelerate support (#15759)

Remove support for Apple Accelerate, since it is buggy. A build error should
occur on most or all setups if linked against Accelerate. Test or import failures
should occur on setups where Accelerate is picked up dynamically.

Co-authored-by: Warren Weckesser <warren.weckesser@gmail.com>

4 files changed, 0 insertions, 287 deletions

diff --git a/numpy/_build_utils/README b/numpy/_build_utils/README
deleted file mode 100644
index 6976e0233..000000000
--- a/numpy/_build_utils/README
+++ /dev/null
@@ -1,8 +0,0 @@
-=======
-WARNING
-=======
-
-This directory (numpy/_build_utils) is *not* part of the public numpy API,
- - it is internal build support for numpy.
- - it is only present in source distributions or during an in place build
- - it is *not* installed with the rest of numpy
diff --git a/numpy/_build_utils/__init__.py b/numpy/_build_utils/__init__.py
deleted file mode 100644
index e69de29bb..000000000
--- a/numpy/_build_utils/__init__.py
+++ /dev/null
diff --git a/numpy/_build_utils/apple_accelerate.py b/numpy/_build_utils/apple_accelerate.py
deleted file mode 100644
index b26aa12ad..000000000
--- a/numpy/_build_utils/apple_accelerate.py
+++ /dev/null
@@ -1,26 +0,0 @@
-import os
-import sys
-import re
-
-__all__ = ['uses_accelerate_framework', 'get_sgemv_fix']
-
-def uses_accelerate_framework(info):
-    """ Returns True if Accelerate framework is used for BLAS/LAPACK """
-    # If we're not building on Darwin (macOS), don't use Accelerate
-    if sys.platform != "darwin":
-        return False
-    # If we're building on macOS, but targeting a different platform,
-    # don't use Accelerate.
-    if os.getenv('_PYTHON_HOST_PLATFORM', None):
-        return False
-    r_accelerate = re.compile("Accelerate")
-    extra_link_args = info.get('extra_link_args', '')
-    for arg in extra_link_args:
-        if r_accelerate.search(arg):
-            return True
-    return False
-
-def get_sgemv_fix():
-    """ Returns source file needed to correct SGEMV """
-    path = os.path.abspath(os.path.dirname(__file__))
-    return [os.path.join(path, 'src', 'apple_sgemv_fix.c')]
diff --git a/numpy/_build_utils/src/apple_sgemv_fix.c b/numpy/_build_utils/src/apple_sgemv_fix.c
deleted file mode 100644
index b1dbeb681..000000000
--- a/numpy/_build_utils/src/apple_sgemv_fix.c
+++ /dev/null
@@ -1,253 +0,0 @@
-/* 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>
-#include <sys/types.h>
-#include <sys/sysctl.h>
-#include <string.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. */
-static inline int 
-cpu_supports_avx() 
-{
-    int enabled, r;
-    size_t length = sizeof(enabled);
-    r = sysctlbyname("hw.optional.avx1_0", &enabled, &length, NULL, 0);
-    if ( r == 0 && enabled != 0) {
-        return 1;
-    }
-    else {
-        return 0;
-    }
-}
-	
-/* Check if we are using MacOS X version 10.9 */
-static inline int 
-using_mavericks() 
-{
-    int r;
-    char str[32] = {0};
-    size_t size = sizeof(str);
-    r = sysctlbyname("kern.osproductversion", str, &size, NULL, 0);
-    if ( r == 0 && strncmp(str, "10.9", strlen("10.9")) == 0) {
-        return 1;
-    }
-    else {
-        return 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 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);
-}