9 files changed, 104 insertions, 2 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index c41c1252374..9ed3a74ef81 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2015-08-11  H.J. Lu  <hongjiu.lu@intel.com>
+
+	* config/i386/i386.h (MOVE_MAX_PIECES): Use TImode in 64-bit
+	mode if unaligned SSE load and store are optimal.
+
 2016-08-11  Bernd Edlinger  <bernd.edlinger@hotmail.de>
 
 	PR tree-optimization/71083
diff --git a/gcc/config/i386/i386.h b/gcc/config/i386/i386.h
index 9b662648f7f..8751143a2a6 100644
--- a/gcc/config/i386/i386.h
+++ b/gcc/config/i386/i386.h
@@ -1950,8 +1950,18 @@ typedef struct ix86_args {
 
 /* MOVE_MAX_PIECES is the number of bytes at a time which we can
    move efficiently, as opposed to  MOVE_MAX which is the maximum
-   number of bytes we can move with a single instruction.  */
-#define MOVE_MAX_PIECES UNITS_PER_WORD
+   number of bytes we can move with a single instruction.
+
+   ??? We should use TImode in 32-bit mode and use OImode or XImode
+   if they are available.  But since by_pieces_ninsns determines the
+   widest mode with MAX_FIXED_MODE_SIZE, we can only use TImode in
+   64-bit mode.  */
+#define MOVE_MAX_PIECES \
+  ((TARGET_64BIT \
+    && TARGET_SSE2 \
+    && TARGET_SSE_UNALIGNED_LOAD_OPTIMAL \
+    && TARGET_SSE_UNALIGNED_STORE_OPTIMAL) \
+   ? GET_MODE_SIZE (TImode) : UNITS_PER_WORD)
 
 /* If a memory-to-memory move would take MOVE_RATIO or more simple
    move-instruction pairs, we will do a movmem or libcall instead.
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index db8a62e3c69..c2482f5dce2 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,12 @@
+2015-08-11  H.J. Lu  <hongjiu.lu@intel.com>
+
+	* gcc.target/i386/pieces-memcpy-1.c: New test.
+	* gcc.target/i386/pieces-memcpy-2.c: Likewise.
+	* gcc.target/i386/pieces-memcpy-3.c: Likewise.
+	* gcc.target/i386/pieces-memcpy-4.c: Likewise.
+	* gcc.target/i386/pieces-memcpy-5.c: Likewise.
+	* gcc.target/i386/pieces-memcpy-6.c: Likewise.
+
 2016-08-11  Jakub Jelinek  <jakub@redhat.com>
 
 	PR c/72816
diff --git a/gcc/testsuite/gcc.target/i386/pieces-memcpy-1.c b/gcc/testsuite/gcc.target/i386/pieces-memcpy-1.c
new file mode 100644
index 00000000000..22202c26f8c
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pieces-memcpy-1.c
@@ -0,0 +1,13 @@
+/* { dg-do compile { target { ! ia32 } } } */
+/* { dg-options "-O2 -mno-avx -msse2 -mtune=generic" } */
+
+extern char *dst, *src;
+
+void
+foo (void)
+{
+  __builtin_memcpy (dst, src, 64);
+}
+
+/* { dg-final { scan-assembler-times "movdqu\[ \\t\]+\[^\n\]*%xmm" 4 } } */
+/* { dg-final { scan-assembler-times "movups\[ \\t\]+\[^\n\]*%xmm" 4 } } */
diff --git a/gcc/testsuite/gcc.target/i386/pieces-memcpy-2.c b/gcc/testsuite/gcc.target/i386/pieces-memcpy-2.c
new file mode 100644
index 00000000000..bc4f05b86c5
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pieces-memcpy-2.c
@@ -0,0 +1,13 @@
+/* { dg-do compile { target { ! ia32 } } } */
+/* { dg-options "-O2 -mno-avx -msse2 -mtune=generic" } */
+
+extern char *dst, *src;
+
+void
+foo (void)
+{
+  __builtin_memcpy (dst, src, 33);
+}
+
+/* { dg-final { scan-assembler-times "movdqu\[ \\t\]+\[^\n\]*%xmm" 2 } } */
+/* { dg-final { scan-assembler-times "movups\[ \\t\]+\[^\n\]*%xmm" 2 } } */
diff --git a/gcc/testsuite/gcc.target/i386/pieces-memcpy-3.c b/gcc/testsuite/gcc.target/i386/pieces-memcpy-3.c
new file mode 100644
index 00000000000..84d6676fca0
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pieces-memcpy-3.c
@@ -0,0 +1,13 @@
+/* { dg-do compile { target { ! ia32 } } } */
+/* { dg-options "-O2 -mno-avx -msse2 -mtune=generic" } */
+
+extern char *dst, *src;
+
+void
+foo (void)
+{
+  __builtin_memcpy (dst, src, 17);
+}
+
+/* { dg-final { scan-assembler-times "movdqu\[ \\t\]+\[^\n\]*%xmm" 1 } } */
+/* { dg-final { scan-assembler-times "movups\[ \\t\]+\[^\n\]*%xmm" 1 } } */
diff --git a/gcc/testsuite/gcc.target/i386/pieces-memcpy-4.c b/gcc/testsuite/gcc.target/i386/pieces-memcpy-4.c
new file mode 100644
index 00000000000..64e8921abe2
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pieces-memcpy-4.c
@@ -0,0 +1,13 @@
+/* { dg-do compile { target { ! ia32 } } } */
+/* { dg-options "-O2 -mno-avx2 -mavx -mtune=generic" } */
+
+extern char *dst, *src;
+
+void
+foo (void)
+{
+  __builtin_memcpy (dst, src, 18);
+}
+
+/* { dg-final { scan-assembler-times "vmovdqu\[ \\t\]+\[^\n\]*%xmm" 1 } } */
+/* { dg-final { scan-assembler-times "vmovups\[ \\t\]+\[^\n\]*%xmm" 1 } } */
diff --git a/gcc/testsuite/gcc.target/i386/pieces-memcpy-5.c b/gcc/testsuite/gcc.target/i386/pieces-memcpy-5.c
new file mode 100644
index 00000000000..3c464c32f8e
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pieces-memcpy-5.c
@@ -0,0 +1,13 @@
+/* { dg-do compile { target { ! ia32 } } } */
+/* { dg-options "-O2 -mavx512f -mtune=generic" } */
+
+extern char *dst, *src;
+
+void
+foo (void)
+{
+  __builtin_memcpy (dst, src, 19);
+}
+
+/* { dg-final { scan-assembler-times "vmovdqu\[ \\t\]+\[^\n\]*%xmm" 1 } } */
+/* { dg-final { scan-assembler-times "vmovups\[ \\t\]+\[^\n\]*%xmm" 1 } } */
diff --git a/gcc/testsuite/gcc.target/i386/pieces-memcpy-6.c b/gcc/testsuite/gcc.target/i386/pieces-memcpy-6.c
new file mode 100644
index 00000000000..cdb00e05bc1
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pieces-memcpy-6.c
@@ -0,0 +1,13 @@
+/* { dg-do compile { target { ! ia32 } } } */
+/* { dg-options "-O2 -mno-avx2 -mavx -mtune=sandybridge" } */
+
+extern char *dst, *src;
+
+void
+foo (void)
+{
+  __builtin_memcpy (dst, src, 33);
+}
+
+/* { dg-final { scan-assembler-times "vmovdqu\[ \\t\]+\[^\n\]*%xmm" 2 } } */
+/* { dg-final { scan-assembler-times "vmovups\[ \\t\]+\[^\n\]*%xmm" 2 } } */