Prepare for radical source tree reorganization. zack/build-layout-experiment

All top-level files and directories are moved into a temporary storage
directory, REORG.TODO, except for files that will certainly still
exist in their current form at top level when we're done (COPYING,
COPYING.LIB, LICENSES, NEWS, README), all old ChangeLog files (which
are moved to the new directory OldChangeLogs, instead), and the
generated file INSTALL (which is just deleted; in the new order, there
will be no generated files checked into version control).

1 files changed, 272 insertions, 0 deletions

diff --git a/REORG.TODO/sysdeps/tile/tilegx/memcpy.c b/REORG.TODO/sysdeps/tile/tilegx/memcpy.c
new file mode 100644
index 0000000000..c1a2a29860
--- /dev/null
+++ b/REORG.TODO/sysdeps/tile/tilegx/memcpy.c
@@ -0,0 +1,272 @@
+/* Copyright (C) 2011-2017 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Chris Metcalf <cmetcalf@tilera.com>, 2011.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <string.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <memcopy.h>
+#include <arch/chip.h>
+
+/* How many cache lines ahead should we prefetch? */
+#define PREFETCH_LINES_AHEAD 3
+
+void * inhibit_loop_to_libcall
+__memcpy (void *__restrict dstv, const void *__restrict srcv, size_t n)
+{
+  char *__restrict dst1 = (char *) dstv;
+  const char *__restrict src1 = (const char *) srcv;
+  const char *__restrict src1_end;
+  const char *__restrict prefetch;
+  op_t *__restrict dst8; /* 8-byte pointer to destination memory. */
+  op_t final; /* Final bytes to write to trailing word, if any */
+  long i;
+
+  if (n < 16)
+    {
+      for (; n; n--)
+        *dst1++ = *src1++;
+      return dstv;
+    }
+
+  /* Locate the end of source memory we will copy.  Don't prefetch
+     past this.  */
+  src1_end = src1 + n - 1;
+
+  /* Prefetch ahead a few cache lines, but not past the end. */
+  prefetch = src1;
+  for (i = 0; i < PREFETCH_LINES_AHEAD; i++)
+    {
+      __insn_prefetch (prefetch);
+      prefetch += CHIP_L2_LINE_SIZE ();
+      prefetch = (prefetch < src1_end) ? prefetch : src1;
+    }
+
+  /* Copy bytes until dst is word-aligned. */
+  for (; (uintptr_t) dst1 & (sizeof (op_t) - 1); n--)
+    *dst1++ = *src1++;
+
+  /* 8-byte pointer to destination memory. */
+  dst8 = (op_t *) dst1;
+
+  if (__builtin_expect ((uintptr_t) src1 & (sizeof (op_t) - 1), 0))
+    {
+      /* Misaligned copy.  Use glibc's _wordcopy_fwd_dest_aligned, but
+         inline it to avoid prologue/epilogue.  TODO: Consider
+         prefetching and using wh64 as well.  */
+      void * srci;
+      op_t a0, a1, a2, a3;
+      long int dstp = (long int) dst1;
+      long int srcp = (long int) src1;
+      long int len = n / OPSIZ;
+
+      /* Save the initial source pointer so we know the number of
+         bytes to shift for merging two unaligned results.  */
+      srci = (void *) srcp;
+
+      /* Make SRCP aligned by rounding it down to the beginning of the
+         `op_t' it points in the middle of.  */
+      srcp &= -OPSIZ;
+
+      switch (len % 4)
+	{
+	case 2:
+	  a1 = ((op_t *) srcp)[0];
+	  a2 = ((op_t *) srcp)[1];
+	  len += 2;
+	  srcp += 2 * OPSIZ;
+	  goto do1;
+	case 3:
+	  a0 = ((op_t *) srcp)[0];
+	  a1 = ((op_t *) srcp)[1];
+	  len += 1;
+	  srcp += 2 * OPSIZ;
+	  goto do2;
+	case 0:
+	  if (OP_T_THRES <= 3 * OPSIZ && len == 0)
+	    return dstv;
+	  a3 = ((op_t *) srcp)[0];
+	  a0 = ((op_t *) srcp)[1];
+	  len += 0;
+	  srcp += 2 * OPSIZ;
+	  goto do3;
+	case 1:
+	  a2 = ((op_t *) srcp)[0];
+	  a3 = ((op_t *) srcp)[1];
+	  srcp += 2 * OPSIZ;
+	  len -= 1;
+	  if (OP_T_THRES <= 3 * OPSIZ && len == 0)
+	    goto do0;
+	  goto do4;			/* No-op.  */
+	}
+
+      do
+	{
+	do4:
+	  a0 = ((op_t *) srcp)[0];
+	  a2 = __insn_dblalign (a2, a3, srci);
+	  ((op_t *) dstp)[0] = a2;
+	  srcp += OPSIZ;
+	  dstp += OPSIZ;
+	do3:
+	  a1 = ((op_t *) srcp)[0];
+	  a3 = __insn_dblalign (a3, a0, srci);
+	  ((op_t *) dstp)[0] = a3;
+	  srcp += OPSIZ;
+	  dstp += OPSIZ;
+	do2:
+	  a2 = ((op_t *) srcp)[0];
+	  a0 = __insn_dblalign (a0, a1, srci);
+	  ((op_t *) dstp)[0] = a0;
+	  srcp += OPSIZ;
+	  dstp += OPSIZ;
+	do1:
+	  a3 = ((op_t *) srcp)[0];
+	  a1 = __insn_dblalign (a1, a2, srci);
+	  ((op_t *) dstp)[0] = a1;
+	  srcp += OPSIZ;
+	  dstp += OPSIZ;
+	  len -= 4;
+	}
+      while (len != 0);
+
+      /* This is the right position for do0.  Please don't move
+         it into the loop.  */
+    do0:
+      ((op_t *) dstp)[0] = __insn_dblalign (a2, a3, srci);
+
+      n = n % OPSIZ;
+      if (n == 0)
+	return dstv;
+
+      a0 = ((const char *) srcp <= src1_end) ? ((op_t *) srcp)[0] : 0;
+
+      final = __insn_dblalign (a3, a0, srci);
+      dst8 = (op_t *)(dstp + OPSIZ);
+    }
+  else
+    {
+      /* Aligned copy. */
+
+      const op_t *__restrict src8 = (const op_t *) src1;
+
+      /* src8 and dst8 are both word-aligned. */
+      if (n >= CHIP_L2_LINE_SIZE ())
+        {
+          /* Copy until 'dst' is cache-line-aligned. */
+          for (; (uintptr_t) dst8 & (CHIP_L2_LINE_SIZE () - 1);
+               n -= sizeof (op_t))
+            *dst8++ = *src8++;
+
+          for (; n >= CHIP_L2_LINE_SIZE ();)
+	    {
+	      op_t tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7;
+
+	      /* Prefetch and advance to next line to prefetch, but
+		 don't go past the end.  */
+	      __insn_prefetch (prefetch);
+	      prefetch += CHIP_L2_LINE_SIZE ();
+	      prefetch = (prefetch < src1_end) ? prefetch :
+		(const char *) src8;
+
+	      /* Do all the loads before wh64.  This is necessary if
+		 [src8, src8+7] and [dst8, dst8+7] share the same
+		 cache line and dst8 <= src8, as can be the case when
+		 called from memmove, or with code tested on x86 whose
+		 memcpy always works with forward copies.  */
+	      tmp0 = *src8++;
+	      tmp1 = *src8++;
+	      tmp2 = *src8++;
+	      tmp3 = *src8++;
+	      tmp4 = *src8++;
+	      tmp5 = *src8++;
+	      tmp6 = *src8++;
+	      tmp7 = *src8++;
+
+	      __insn_wh64 (dst8);
+
+	      *dst8++ = tmp0;
+	      *dst8++ = tmp1;
+	      *dst8++ = tmp2;
+	      *dst8++ = tmp3;
+	      *dst8++ = tmp4;
+	      *dst8++ = tmp5;
+	      *dst8++ = tmp6;
+	      *dst8++ = tmp7;
+
+	      n -= 64;
+	    }
+#if CHIP_L2_LINE_SIZE() != 64
+# error "Fix code that assumes particular L2 cache line size."
+#endif
+        }
+
+      for (; n >= sizeof (op_t); n -= sizeof (op_t))
+        *dst8++ = *src8++;
+
+      if (__builtin_expect (n == 0, 1))
+        return dstv;
+
+      final = *src8;
+    }
+
+  /* n != 0 if we get here.  Write out any trailing bytes. */
+  dst1 = (char *) dst8;
+#ifndef __BIG_ENDIAN__
+  if (n & 4)
+    {
+      *(uint32_t *) dst1 = final;
+      dst1 += 4;
+      final >>= 32;
+      n &= 3;
+    }
+  if (n & 2)
+    {
+      *(uint16_t *) dst1 = final;
+      dst1 += 2;
+      final >>= 16;
+      n &= 1;
+    }
+  if (n)
+    *(uint8_t *) dst1 = final;
+#else
+  if (n & 4)
+    {
+      *(uint32_t *) dst1 = final >> 32;
+      dst1 += 4;
+    }
+  else
+    {
+      final >>= 32;
+    }
+  if (n & 2)
+    {
+      *(uint16_t *) dst1 = final >> 16;
+      dst1 += 2;
+    }
+  else
+    {
+      final >>= 16;
+    }
+  if (n & 1)
+    *(uint8_t *) dst1 = final >> 8;
+#endif
+
+  return dstv;
+}
+weak_alias (__memcpy, memcpy)
+libc_hidden_builtin_def (memcpy)