176 lines
6.1 KiB
Diff
176 lines
6.1 KiB
Diff
2018-01-30 Jeff Law <law@redhat.com>
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PR target/84064
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* i386.c (ix86_adjust_stack_and_probe_stack_clash): New argument
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INT_REGISTERS_SAVED. Check it prior to calling
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get_scratch_register_on_entry.
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(ix86_adjust_stack_and_probe): Similarly.
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(ix86_emit_probe_stack_range): Similarly.
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(ix86_expand_prologue): Corresponding changes.
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* gcc.target/i386/pr84064: New test.
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--- gcc/config/i386/i386.c
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+++ gcc/config/i386/i386.c
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@@ -12591,10 +12591,14 @@ release_scratch_register_on_entry (struct scratch_reg *sr)
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This differs from the next routine in that it tries hard to prevent
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attacks that jump the stack guard. Thus it is never allowed to allocate
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more than PROBE_INTERVAL bytes of stack space without a suitable
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- probe. */
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+ probe.
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+
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+ INT_REGISTERS_SAVED is true if integer registers have already been
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+ pushed on the stack. */
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static void
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-ix86_adjust_stack_and_probe_stack_clash (const HOST_WIDE_INT size)
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+ix86_adjust_stack_and_probe_stack_clash (const HOST_WIDE_INT size,
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+ const bool int_registers_saved)
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{
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struct machine_function *m = cfun->machine;
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@@ -12700,6 +12704,12 @@ ix86_adjust_stack_and_probe_stack_clash (const HOST_WIDE_INT size)
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}
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else
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{
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+ /* We expect the GP registers to be saved when probes are used
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+ as the probing sequences might need a scratch register and
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+ the routine to allocate one assumes the integer registers
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+ have already been saved. */
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+ gcc_assert (int_registers_saved);
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+
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struct scratch_reg sr;
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get_scratch_register_on_entry (&sr);
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@@ -12758,10 +12768,14 @@ ix86_adjust_stack_and_probe_stack_clash (const HOST_WIDE_INT size)
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emit_insn (gen_blockage ());
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}
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-/* Emit code to adjust the stack pointer by SIZE bytes while probing it. */
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+/* Emit code to adjust the stack pointer by SIZE bytes while probing it.
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+
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+ INT_REGISTERS_SAVED is true if integer registers have already been
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+ pushed on the stack. */
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static void
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-ix86_adjust_stack_and_probe (const HOST_WIDE_INT size)
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+ix86_adjust_stack_and_probe (const HOST_WIDE_INT size,
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+ const bool int_registers_saved)
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{
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/* We skip the probe for the first interval + a small dope of 4 words and
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probe that many bytes past the specified size to maintain a protection
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@@ -12822,6 +12836,12 @@ ix86_adjust_stack_and_probe (const HOST_WIDE_INT size)
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equality test for the loop condition. */
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else
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{
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+ /* We expect the GP registers to be saved when probes are used
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+ as the probing sequences might need a scratch register and
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+ the routine to allocate one assumes the integer registers
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+ have already been saved. */
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+ gcc_assert (int_registers_saved);
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+
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HOST_WIDE_INT rounded_size;
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struct scratch_reg sr;
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@@ -12949,10 +12969,14 @@ output_adjust_stack_and_probe (rtx reg)
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}
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/* Emit code to probe a range of stack addresses from FIRST to FIRST+SIZE,
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- inclusive. These are offsets from the current stack pointer. */
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+ inclusive. These are offsets from the current stack pointer.
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+
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+ INT_REGISTERS_SAVED is true if integer registers have already been
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+ pushed on the stack. */
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static void
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-ix86_emit_probe_stack_range (HOST_WIDE_INT first, HOST_WIDE_INT size)
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+ix86_emit_probe_stack_range (HOST_WIDE_INT first, HOST_WIDE_INT size,
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+ const bool int_registers_saved)
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{
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/* See if we have a constant small number of probes to generate. If so,
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that's the easy case. The run-time loop is made up of 6 insns in the
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@@ -12980,6 +13004,12 @@ ix86_emit_probe_stack_range (HOST_WIDE_INT first, HOST_WIDE_INT size)
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equality test for the loop condition. */
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else
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{
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+ /* We expect the GP registers to be saved when probes are used
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+ as the probing sequences might need a scratch register and
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+ the routine to allocate one assumes the integer registers
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+ have already been saved. */
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+ gcc_assert (int_registers_saved);
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+
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HOST_WIDE_INT rounded_size, last;
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struct scratch_reg sr;
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@@ -13733,15 +13763,10 @@ ix86_expand_prologue (void)
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&& (flag_stack_check == STATIC_BUILTIN_STACK_CHECK
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|| flag_stack_clash_protection))
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{
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- /* We expect the GP registers to be saved when probes are used
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- as the probing sequences might need a scratch register and
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- the routine to allocate one assumes the integer registers
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- have already been saved. */
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- gcc_assert (int_registers_saved);
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-
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if (flag_stack_clash_protection)
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{
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- ix86_adjust_stack_and_probe_stack_clash (allocate);
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+ ix86_adjust_stack_and_probe_stack_clash (allocate,
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+ int_registers_saved);
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allocate = 0;
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}
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else if (STACK_CHECK_MOVING_SP)
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@@ -13749,7 +13774,7 @@ ix86_expand_prologue (void)
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if (!(crtl->is_leaf && !cfun->calls_alloca
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&& allocate <= get_probe_interval ()))
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{
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- ix86_adjust_stack_and_probe (allocate);
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+ ix86_adjust_stack_and_probe (allocate, int_registers_saved);
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allocate = 0;
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}
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}
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@@ -13765,11 +13790,12 @@ ix86_expand_prologue (void)
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if (crtl->is_leaf && !cfun->calls_alloca)
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{
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if (size > get_probe_interval ())
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- ix86_emit_probe_stack_range (0, size);
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+ ix86_emit_probe_stack_range (0, size, int_registers_saved);
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}
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else
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ix86_emit_probe_stack_range (0,
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- size + get_stack_check_protect ());
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+ size + get_stack_check_protect (),
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+ int_registers_saved);
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}
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else
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{
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@@ -13778,10 +13804,13 @@ ix86_expand_prologue (void)
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if (size > get_probe_interval ()
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&& size > get_stack_check_protect ())
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ix86_emit_probe_stack_range (get_stack_check_protect (),
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- size - get_stack_check_protect ());
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+ (size
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+ - get_stack_check_protect ()),
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+ int_registers_saved);
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}
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else
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- ix86_emit_probe_stack_range (get_stack_check_protect (), size);
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+ ix86_emit_probe_stack_range (get_stack_check_protect (), size,
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+ int_registers_saved);
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}
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}
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}
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--- gcc/testsuite/gcc.target/i386/pr84064.c
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+++ gcc/testsuite/gcc.target/i386/pr84064.c
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@@ -0,0 +1,10 @@
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+/* { dg-do compile } */
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+/* { dg-options "-O2 -march=i686 -fstack-clash-protection" } */
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+/* { dg-require-effective-target ia32 } */
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+
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+void
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+f (void *p1, void *p2)
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+{
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+ __builtin_memcpy (p1, p2, 1000);
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+}
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+
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