From e52d6c1aed5a688fd28b9f6e005c6d9f3857b9cf Mon Sep 17 00:00:00 2001
From: "H.J. Lu" <hjl.tools@gmail.com>
Date: Mon, 8 Aug 2016 09:08:01 -0700
Subject: [PATCH] Use TImode for piecewise move in 64-bit mode

Use TImode for piecewise move in 64-bit mode.  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.

gcc/

	* config/i386/i386.h (MOVE_MAX_PIECES): Use TImode in 64-bit
	mode if unaligned SSE load and store are optimal.

gcc/testsuite/

	* 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.
---
 gcc/config/i386/i386.h                          | 14 ++++++++++++--
 gcc/testsuite/gcc.target/i386/pieces-memcpy-1.c | 13 +++++++++++++
 gcc/testsuite/gcc.target/i386/pieces-memcpy-2.c | 13 +++++++++++++
 gcc/testsuite/gcc.target/i386/pieces-memcpy-3.c | 13 +++++++++++++
 gcc/testsuite/gcc.target/i386/pieces-memcpy-4.c | 13 +++++++++++++
 gcc/testsuite/gcc.target/i386/pieces-memcpy-5.c | 13 +++++++++++++
 gcc/testsuite/gcc.target/i386/pieces-memcpy-6.c | 13 +++++++++++++
 7 files changed, 90 insertions(+), 2 deletions(-)
 create mode 100644 gcc/testsuite/gcc.target/i386/pieces-memcpy-1.c
 create mode 100644 gcc/testsuite/gcc.target/i386/pieces-memcpy-2.c
 create mode 100644 gcc/testsuite/gcc.target/i386/pieces-memcpy-3.c
 create mode 100644 gcc/testsuite/gcc.target/i386/pieces-memcpy-4.c
 create mode 100644 gcc/testsuite/gcc.target/i386/pieces-memcpy-5.c
 create mode 100644 gcc/testsuite/gcc.target/i386/pieces-memcpy-6.c

diff --git a/gcc/config/i386/i386.h b/gcc/config/i386/i386.h
index 9b66264..8751143 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/gcc.target/i386/pieces-memcpy-1.c b/gcc/testsuite/gcc.target/i386/pieces-memcpy-1.c
new file mode 100644
index 0000000..22202c2
--- /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 0000000..bc4f05b
--- /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 0000000..84d6676
--- /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 0000000..64e8921
--- /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 0000000..3c464c3
--- /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 0000000..cdb00e0
--- /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 } } */
-- 
2.7.4

