compat-libgfortran-48/SOURCES/gcc48-rh1537828-2.patch
2022-05-17 15:21:39 +00:00

115 lines
4.0 KiB
Diff

commit f7765f70e0e254fd9ce4469c7281c69cd06c9467
Author: law <law@138bc75d-0d04-0410-961f-82ee72b054a4>
Date: Wed Jan 24 21:57:16 2018 +0000
PR target/83994
* i386.c (get_probe_interval): Move to earlier point.
(ix86_compute_frame_layout): If -fstack-clash-protection and
the frame is larger than the probe interval, then use pushes
to save registers rather than reg->mem moves.
(ix86_expand_prologue): Remove conditional for int_registers_saved
assertion.
PR target/83994
* gcc.target/i386/pr83994.c: New test.
diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
index 15cfe83..5230227 100644
--- a/gcc/config/i386/i386.c
+++ b/gcc/config/i386/i386.c
@@ -9371,6 +9371,18 @@ ix86_builtin_setjmp_frame_value (void)
return stack_realign_fp ? hard_frame_pointer_rtx : virtual_stack_vars_rtx;
}
+/* Return the probing interval for -fstack-clash-protection. */
+
+static HOST_WIDE_INT
+get_probe_interval (void)
+{
+ if (flag_stack_clash_protection)
+ return (HOST_WIDE_INT_1U
+ << PARAM_VALUE (PARAM_STACK_CLASH_PROTECTION_PROBE_INTERVAL));
+ else
+ return (HOST_WIDE_INT_1U << STACK_CHECK_PROBE_INTERVAL_EXP);
+}
+
/* When using -fsplit-stack, the allocation routines set a field in
the TCB to the bottom of the stack plus this much space, measured
in bytes. */
@@ -9545,7 +9557,15 @@ ix86_compute_frame_layout (struct ix86_frame *frame)
to_allocate = offset - frame->sse_reg_save_offset;
if ((!to_allocate && frame->nregs <= 1)
- || (TARGET_64BIT && to_allocate >= (HOST_WIDE_INT) 0x80000000))
+ || (TARGET_64BIT && to_allocate >= (HOST_WIDE_INT) 0x80000000)
+ /* If stack clash probing needs a loop, then it needs a
+ scratch register. But the returned register is only guaranteed
+ to be safe to use after register saves are complete. So if
+ stack clash protections are enabled and the allocated frame is
+ larger than the probe interval, then use pushes to save
+ callee saved registers. */
+ || (flag_stack_clash_protection && to_allocate > get_probe_interval ()))
+
frame->save_regs_using_mov = false;
if (ix86_using_red_zone ()
@@ -10181,18 +10201,6 @@ release_scratch_register_on_entry (struct scratch_reg *sr)
}
}
-/* Return the probing interval for -fstack-clash-protection. */
-
-static HOST_WIDE_INT
-get_probe_interval (void)
-{
- if (flag_stack_clash_protection)
- return (HOST_WIDE_INT_1U
- << PARAM_VALUE (PARAM_STACK_CLASH_PROTECTION_PROBE_INTERVAL));
- else
- return (HOST_WIDE_INT_1U << STACK_CHECK_PROBE_INTERVAL_EXP);
-}
-
/* Emit code to adjust the stack pointer by SIZE bytes while probing it.
This differs from the next routine in that it tries hard to prevent
@@ -11064,12 +11072,11 @@ ix86_expand_prologue (void)
&& (flag_stack_check == STATIC_BUILTIN_STACK_CHECK
|| flag_stack_clash_protection))
{
- /* This assert wants to verify that integer registers were saved
- prior to probing. This is necessary when probing may be implemented
- as a function call (Windows). It is not necessary for stack clash
- protection probing. */
- if (!flag_stack_clash_protection)
- gcc_assert (int_registers_saved);
+ /* We expect the GP registers to be saved when probes are used
+ as the probing sequences might need a scratch register and
+ the routine to allocate one assumes the integer registers
+ have already been saved. */
+ gcc_assert (int_registers_saved);
if (flag_stack_clash_protection)
{
diff --git a/gcc/testsuite/gcc.target/i386/pr83994.c b/gcc/testsuite/gcc.target/i386/pr83994.c
new file mode 100644
index 0000000..dc0b7cb
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr83994.c
@@ -0,0 +1,16 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -march=i686 -fpic -fstack-clash-protection" } */
+/* { dg-require-effective-target ia32 } */
+
+void f1 (char *);
+
+__attribute__ ((regparm (3)))
+int
+f2 (int arg1, int arg2, int arg3)
+{
+ char buf[16384];
+ f1 (buf);
+ f1 (buf);
+ return 0;
+}
+