Factorize MAX_STACK_ALLOC code to common_stackalloc.h

Ref #727

common.h

@@ -727,6 +727,7 @@ typedef struct {
 #endif
 
 #ifndef ASSEMBLER
+#include "common_stackalloc.h"
 #if 0
 #include "symcopy.h"
 #endif

common_stackalloc.h

@@ -0,0 +1,73 @@
+/*******************************************************************************
+Copyright (c) 2016, The OpenBLAS Project
+All rights reserved.
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+1. Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+2. Redistributions in binary form must reproduce the above copyright
+notice, this list of conditions and the following disclaimer in
+the documentation and/or other materials provided with the
+distribution.
+3. Neither the name of the OpenBLAS project nor the names of
+its contributors may be used to endorse or promote products
+derived from this software without specific prior written permission.
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ARE DISCLAIMED. IN NO EVENT SHALL THE OPENBLAS PROJECT OR CONTRIBUTORS BE
+LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
+USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*******************************************************************************/
+
+#define STACK_ALLOC_PROTECT
+#ifdef STACK_ALLOC_PROTECT
+// Try to detect stack smashing
+#include <assert.h>
+#define STACK_ALLOC_PROTECT_SET volatile BLASLONG stack_check = 0x7ff8010203040506;
+#define STACK_ALLOC_PROTECT_CHECK assert(stack_check == 0x7ff8010203040506);
+#else
+#define STACK_ALLOC_PROTECT_SET
+#define STACK_ALLOC_PROTECT_CHECK
+#endif
+
+#if defined(MAX_STACK_ALLOC) && MAX_STACK_ALLOC > 0
+
+/*
+ * Allocate a buffer on the stack if the size is smaller than MAX_STACK_ALLOC.
+ * Stack allocation is much faster than blas_memory_alloc or malloc, particularly
+ * when OpenBLAS is used from a multi-threaded application.
+ * SIZE must be carefully chosen to be:
+ * - as small as possible to maximize the number of stack allocation
+ * - large enough to support all architectures and kernel
+ * Chosing a too small SIZE will lead to a stack smashing.
+ */
+#define STACK_ALLOC(SIZE, TYPE, BUFFER)                                    \
+  /* make it volatile because some function (ex: dgemv_n.S) */             \
+  /* do not restore all register */                                        \
+  volatile int stack_alloc_size = SIZE;                                    \
+  if(stack_alloc_size > MAX_STACK_ALLOC / sizeof(TYPE))                    \
+    stack_alloc_size = 0;                                                  \
+  STACK_ALLOC_PROTECT_SET                                                  \
+  TYPE stack_buffer[stack_alloc_size];                                     \
+  BUFFER = stack_alloc_size ? stack_buffer : (TYPE *)blas_memory_alloc(1);
+#else
+  //Original OpenBLAS/GotoBLAS codes.
+  #define STACK_ALLOC(SIZE, TYPE, BUFFER) BUFFER = (TYPE *)blas_memory_alloc(1)
+#endif
+
+
+#if defined(MAX_STACK_ALLOC) && MAX_STACK_ALLOC > 0
+#define STACK_FREE(BUFFER)    \
+  STACK_ALLOC_PROTECT_CHECK   \
+  if(!stack_alloc_size)       \
+    blas_memory_free(BUFFER);
+#else
+#define STACK_FREE(BUFFER) blas_memory_free(BUFFER)
+#endif
+

interface/gemv.c

@@ -37,7 +37,6 @@
 /*********************************************************************/
 
 #include <stdio.h>
-#include <assert.h>
 #include "common.h"
 #include "l1param.h"
 #ifdef FUNCTION_PROFILE
@@ -80,6 +79,7 @@ void NAME(char *TRANS, blasint *M, blasint *N,
   FLOAT alpha = *ALPHA;
   FLOAT beta  = *BETA;
   FLOAT *buffer;
+  int buffer_size;
 #ifdef SMP
   int nthreads;
   int nthreads_max;
@@ -135,7 +135,7 @@ void CNAME(enum CBLAS_ORDER order,
 
   FLOAT *buffer;
   blasint lenx, leny;
-  int trans;
+  int trans, buffer_size;
   blasint info, t;
 #ifdef SMP
   int nthreads;
@@ -216,33 +216,13 @@ void CNAME(enum CBLAS_ORDER order,
   if (incx < 0) x -= (lenx - 1) * incx;
   if (incy < 0) y -= (leny - 1) * incy;
 
-#ifdef MAX_STACK_ALLOC
-  // make it volatile because some gemv implementation (ex: dgemv_n.S)
-  // do not restore all register
-  volatile int stack_alloc_size = 0;
-  //for gemv_n and gemv_t, try to allocate on stack
-  stack_alloc_size = m + n;
-#ifdef ALIGNED_ACCESS
-  stack_alloc_size += 3;
-#endif
-//  if(stack_alloc_size < 128)
-    //dgemv_n.S require a 128 bytes buffer
-// increasing instead of capping 128 
-// ABI STACK for windows 288 bytes
-    stack_alloc_size += 288 / sizeof(FLOAT) ;
-
-  if(stack_alloc_size > MAX_STACK_ALLOC / sizeof(FLOAT))
-    stack_alloc_size = 0;
-
-// stack overflow check
-  volatile double stack_check = 3.14159265358979323846;
-  FLOAT stack_buffer[stack_alloc_size];
-  buffer = stack_alloc_size ? stack_buffer : (FLOAT *)blas_memory_alloc(1);
-  //  printf("stack_alloc_size=%d\n", stack_alloc_size);
-#else
-  //Original OpenBLAS/GotoBLAS codes.
-  buffer = (FLOAT *)blas_memory_alloc(1);
+  buffer_size = m + n + 128 / sizeof(FLOAT);
+#ifdef WINDOWS_ABI
+  buffer_size += 160 / sizeof(FLOAT) ;
 #endif
+  // for alignment
+  buffer_size = (buffer_size + 3) & ~3;
+  STACK_ALLOC(buffer_size, FLOAT, buffer);
 
 #ifdef SMP
 
@@ -271,17 +251,7 @@ void CNAME(enum CBLAS_ORDER order,
   }
 #endif
 
-#ifdef MAX_STACK_ALLOC
-  // stack overflow check
-  assert(stack_check==3.14159265358979323846);
-
-  if(!stack_alloc_size){
-    blas_memory_free(buffer);
-  }
-#else
-    blas_memory_free(buffer);
-#endif
-  
+  STACK_FREE(buffer);
   FUNCTION_PROFILE_END(1, m * n + m + n,  2 * m * n);
 
   IDEBUG_END;

interface/ger.c

@@ -171,15 +171,7 @@ void CNAME(enum CBLAS_ORDER order,
   if (incy < 0) y -= (n - 1) * incy;
   if (incx < 0) x -= (m - 1) * incx;
 
-#ifdef MAX_STACK_ALLOC
-  volatile int stack_alloc_size = m;
-  if(stack_alloc_size > MAX_STACK_ALLOC / sizeof(FLOAT))
-      stack_alloc_size = 0;
-  FLOAT stack_buffer[stack_alloc_size];
-  buffer = stack_alloc_size ? stack_buffer : (FLOAT *)blas_memory_alloc(1);
-#else
-  buffer = (FLOAT *)blas_memory_alloc(1);
-#endif
+  STACK_ALLOC(m, FLOAT, buffer);
 
 #ifdef SMPTEST
   nthreads = num_cpu_avail(2);
@@ -198,11 +190,7 @@ void CNAME(enum CBLAS_ORDER order,
   }
 #endif
 
-#ifdef MAX_STACK_ALLOC
-  if(!stack_alloc_size)
-#endif
-    blas_memory_free(buffer);
-
+  STACK_FREE(buffer);
   FUNCTION_PROFILE_END(1, m * n + m + n, 2 * m * n);
 
   IDEBUG_END;