From f7ccc9fc8419d08d8dbf9bd3ed3eec244196a6db Mon Sep 17 00:00:00 2001
From: "H.J. Lu" <hjl.tools@gmail.com>
Date: Wed, 26 Jul 2017 09:06:22 -0700
Subject: [PATCH] x86: Properly check saved register CFA offset
X86 prologue saves register at CFA offset. Since its location on stack
is computed as CFA - its CFA_OFFSET, CFA_OFFSET points the end of the
saved register area on stack. This patch updates sp_valid_at and
fp_valid_at to properly check saved register CFA offset.
gcc/
PR target/81563
* config/i386/i386.c (sp_valid_at): Properly check CFA offset.
(fp_valid_at): Likewise.
gcc/testsuite/
PR target/81563
* gcc.target/i386/pr81563.c: New test
---
gcc/config/i386/i386.c | 10 ++++++----
gcc/testsuite/gcc.target/i386/pr81563.c | 14 ++++++++++++++
2 files changed, 20 insertions(+), 4 deletions(-)
create mode 100644 gcc/testsuite/gcc.target/i386/pr81563.c
@@ -13102,24 +13102,26 @@ choose_baseaddr_len (unsigned int regno, HOST_WIDE_INT offset)
return len;
}
-/* Determine if the stack pointer is valid for accessing the cfa_offset. */
+/* Determine if the stack pointer is valid for accessing the cfa_offset.
+ The register is saved at CFA - CFA_OFFSET. */
static inline bool
sp_valid_at (HOST_WIDE_INT cfa_offset)
{
const struct machine_frame_state &fs = cfun->machine->fs;
return fs.sp_valid && !(fs.sp_realigned
- && cfa_offset < fs.sp_realigned_offset);
+ && cfa_offset <= fs.sp_realigned_offset);
}
-/* Determine if the frame pointer is valid for accessing the cfa_offset. */
+/* Determine if the frame pointer is valid for accessing the cfa_offset.
+ The register is saved at CFA - CFA_OFFSET. */
static inline bool
fp_valid_at (HOST_WIDE_INT cfa_offset)
{
const struct machine_frame_state &fs = cfun->machine->fs;
return fs.fp_valid && !(fs.sp_valid && fs.sp_realigned
- && cfa_offset >= fs.sp_realigned_offset);
+ && cfa_offset > fs.sp_realigned_offset);
}
/* Choose a base register based upon alignment requested, speed and/or
new file mode 100644
@@ -0,0 +1,14 @@
+/* { dg-do compile { target ia32 } } */
+/* { dg-options "-O2 -maccumulate-outgoing-args -mincoming-stack-boundary=2 -mpreferred-stack-boundary=3 -mregparm=3 -mtune-ctrl=epilogue_using_move" } */
+
+extern void bar (long long int, int);
+
+long long int
+fn1 (long long int x)
+{
+ bar (x, 1);
+ return x;
+}
+
+/* { dg-final { scan-assembler-times "movl\[\\t \]*-8\\(%ebp\\),\[\\t \]*%esi" 1 } } */
+/* { dg-final { scan-assembler-times "movl\[\\t \]*-4\\(%ebp\\),\[\\t \]*%edi" 1 } } */
--
2.13.3