From 86e040399dd5ca6b23597be4aff5edb9ac2ab5d7 Mon Sep 17 00:00:00 2001
From: "H.J. Lu" <hjl.tools@gmail.com>
Date: Mon, 25 Jan 2016 12:31:45 -0800
Subject: [PATCH] Don't align DImode to 32 bits if the STV pass is enabled
Since the STV pass uses SSE2 instructions on DImode which needs 64-bit
alignment for DImode, don't align DImode to 32 bits if the STV pass is
enabled.
gcc/
PR target/69454
* config/i386/i386.c (convert_scalars_to_vector): Don't change
stack alignment here.
(ix86_minimum_alignment): Don't align DImode to 32 bits if the
STV pass is enabled.
gcc/testsuite/
PR target/69454
* gcc.target/i386/pr69454-1.c: New test.
* gcc.target/i386/pr69454-2.c: Likewise.
---
gcc/config/i386/i386.c | 16 ++++------------
gcc/testsuite/gcc.target/i386/pr69454-1.c | 11 +++++++++++
gcc/testsuite/gcc.target/i386/pr69454-2.c | 13 +++++++++++++
3 files changed, 28 insertions(+), 12 deletions(-)
create mode 100644 gcc/testsuite/gcc.target/i386/pr69454-1.c
create mode 100644 gcc/testsuite/gcc.target/i386/pr69454-2.c
@@ -3588,16 +3588,6 @@ convert_scalars_to_vector ()
bitmap_obstack_release (NULL);
df_process_deferred_rescans ();
- /* Conversion means we may have 128bit register spills/fills
- which require aligned stack. */
- if (converted_insns)
- {
- if (crtl->stack_alignment_needed < 128)
- crtl->stack_alignment_needed = 128;
- if (crtl->stack_alignment_estimated < 128)
- crtl->stack_alignment_estimated = 128;
- }
-
return 0;
}
@@ -29299,8 +29289,10 @@ ix86_minimum_alignment (tree exp, machine_mode mode,
return align;
/* Don't do dynamic stack realignment for long long objects with
- -mpreferred-stack-boundary=2. */
- if ((mode == DImode || (type && TYPE_MODE (type) == DImode))
+ -mpreferred-stack-boundary=2. The STV pass uses SSE2 instructions
+ on DImode which needs 64-bit alignment for DImode. */
+ if (!(TARGET_STV && TARGET_SSE2 && optimize > 1)
+ && (mode == DImode || (type && TYPE_MODE (type) == DImode))
&& (!type || !TYPE_USER_ALIGN (type))
&& (!decl || !DECL_USER_ALIGN (decl)))
return 32;
new file mode 100644
@@ -0,0 +1,11 @@
+/* { dg-do compile { target { ia32 } } } */
+/* { dg-options "-O2 -msse2 -mno-accumulate-outgoing-args -mpreferred-stack-boundary=2" } */
+
+typedef struct { long long w64[2]; } V128;
+extern V128* fn2(void);
+long long a;
+V128 b;
+void fn1() {
+ V128 *c = fn2();
+ c->w64[0] = a ^ b.w64[0];
+}
new file mode 100644
@@ -0,0 +1,13 @@
+/* { dg-do compile { target { ia32 } } } */
+/* { dg-options "-O2 -msse2 -mno-accumulate-outgoing-args -mpreferred-stack-boundary=2" } */
+
+extern void fn2 (void);
+long long a, b;
+void
+fn1 (void)
+{
+ long long c = a;
+ a = b ^ a;
+ fn2 ();
+ a = c;
+}
--
2.5.0