We currently read and write beyond the builtin jmpbuf on ILP32 targets
where Pmode == DImode and ptr_mode == SImode. Since the builtin jmpbuf
is an array of 5 pointers, ptr_mode should be used to save and restore
frame and program pointers. Since x86 only saves stack pointer in
stack save area, STACK_SAVEAREA_MODE should be ptr_mode, not Pmode.
Note: If ptr_mode != Pmode, builtin setjmp/longjmp tests may fail. When
it happens, please check if there are correct save_stack_nonlocal and
restore_stack_nonlocal expand patterns.
Tested on i686 and x86-64. OK for trunk?
H.J.
----
gcc/
PR middle-end/84150
* builtins.c (expand_builtin_setjmp_setup): Use ptr_mode to
save frame and program pointers.
(expand_builtin_longjmp): Use ptr_mode to restore frame and
program pointers.
* config/i386/i386.md (save_stack_nonlocal): New expand pattern.
(restore_stack_nonlocal): Likewise.
* config/i386/i386.h (STACK_SAVEAREA_MODE): New.
gcc/testsuite/
PR middle-end/84150
* gcc.dg/pr84150.c: New test.
* gcc.target/i386/pr84150.c: Likewisde.
---
gcc/builtins.c | 36 +++++++++++++++++---------
gcc/config/i386/i386.h | 4 +++
gcc/config/i386/i386.md | 36 ++++++++++++++++++++++++++
gcc/testsuite/gcc.dg/pr84150.c | 45 +++++++++++++++++++++++++++++++++
gcc/testsuite/gcc.target/i386/pr84150.c | 44 ++++++++++++++++++++++++++++++++
5 files changed, 153 insertions(+), 12 deletions(-)
create mode 100644 gcc/testsuite/gcc.dg/pr84150.c
create mode 100644 gcc/testsuite/gcc.target/i386/pr84150.c
diff --git a/gcc/builtins.c b/gcc/builtins.c
index 683c6ec6e5b..c3d45d5e3fa 100644
--- a/gcc/builtins.c
+++ b/gcc/builtins.c
@@ -840,6 +840,7 @@ expand_builtin_setjmp_setup (rtx buf_addr, rtx
receiver_label)
machine_mode sa_mode = STACK_SAVEAREA_MODE (SAVE_NONLOCAL);
rtx stack_save;
rtx mem;
+ rtx tmp;
if (setjmp_alias_set == -1)
setjmp_alias_set = new_alias_set ();
@@ -852,20 +853,25 @@ expand_builtin_setjmp_setup (rtx buf_addr, rtx
receiver_label)
the buffer and use the rest of it for the stack save area, which
is machine-dependent. */
- mem = gen_rtx_MEM (Pmode, buf_addr);
+ mem = gen_rtx_MEM (ptr_mode, buf_addr);
set_mem_alias_set (mem, setjmp_alias_set);
- emit_move_insn (mem, targetm.builtin_setjmp_frame_value ());
+ tmp = targetm.builtin_setjmp_frame_value ();
+ if (GET_MODE (tmp) != ptr_mode)
+ tmp = gen_lowpart (ptr_mode, tmp);
+ emit_move_insn (mem, tmp);
- mem = gen_rtx_MEM (Pmode, plus_constant (Pmode, buf_addr,
- GET_MODE_SIZE (Pmode))),
+ mem = gen_rtx_MEM (ptr_mode, plus_constant (Pmode, buf_addr,
+ GET_MODE_SIZE (ptr_mode))),
set_mem_alias_set (mem, setjmp_alias_set);
- emit_move_insn (validize_mem (mem),
- force_reg (Pmode, gen_rtx_LABEL_REF (Pmode, receiver_label)));
+ tmp = force_reg (Pmode, gen_rtx_LABEL_REF (Pmode, receiver_label));
+ if (Pmode != ptr_mode)
+ tmp = gen_lowpart (ptr_mode, tmp);
+ emit_move_insn (validize_mem (mem), tmp);
stack_save = gen_rtx_MEM (sa_mode,
plus_constant (Pmode, buf_addr,
- 2 * GET_MODE_SIZE (Pmode)));
+ 2 * GET_MODE_SIZE (ptr_mode)));
set_mem_alias_set (stack_save, setjmp_alias_set);
emit_stack_save (SAVE_NONLOCAL, &stack_save);
@@ -991,12 +997,14 @@ expand_builtin_longjmp (rtx buf_addr, rtx value)
emit_insn (targetm.gen_builtin_longjmp (buf_addr));
else
{
- fp = gen_rtx_MEM (Pmode, buf_addr);
- lab = gen_rtx_MEM (Pmode, plus_constant (Pmode, buf_addr,
- GET_MODE_SIZE (Pmode)));
+ fp = gen_rtx_MEM (ptr_mode, buf_addr);
+ lab = gen_rtx_MEM (ptr_mode,
+ plus_constant (Pmode, buf_addr,
+ GET_MODE_SIZE (ptr_mode)));
- stack = gen_rtx_MEM (sa_mode, plus_constant (Pmode, buf_addr,
- 2 * GET_MODE_SIZE (Pmode)));
+ stack = gen_rtx_MEM (sa_mode,
+ plus_constant (Pmode, buf_addr,
+ 2 * GET_MODE_SIZE (ptr_mode)));
set_mem_alias_set (fp, setjmp_alias_set);
set_mem_alias_set (lab, setjmp_alias_set);
set_mem_alias_set (stack, setjmp_alias_set);
@@ -1015,6 +1023,10 @@ expand_builtin_longjmp (rtx buf_addr, rtx value)
emit_clobber (gen_rtx_MEM (BLKmode, gen_rtx_SCRATCH (VOIDmode)));
emit_clobber (gen_rtx_MEM (BLKmode, hard_frame_pointer_rtx));
+#ifdef POINTERS_EXTEND_UNSIGNED
+ if (GET_MODE (fp) != Pmode)
+ fp = convert_to_mode (Pmode, fp, POINTERS_EXTEND_UNSIGNED);
+#endif
emit_move_insn (hard_frame_pointer_rtx, fp);
emit_stack_restore (SAVE_NONLOCAL, stack);
diff --git a/gcc/config/i386/i386.h b/gcc/config/i386/i386.h
index 59522ccba02..16aace86e48 100644
--- a/gcc/config/i386/i386.h
+++ b/gcc/config/i386/i386.h
@@ -1937,6 +1937,10 @@ do {
\
between pointers and any other objects of this machine mode. */
#define Pmode (ix86_pmode == PMODE_DI ? DImode : SImode)
+/* Supply a definition of STACK_SAVEAREA_MODE for emit_stack_save. We
+ only need save and restore stack pointer in ptr_mode. */
+#define STACK_SAVEAREA_MODE(LEVEL) ptr_mode
+
/* Specify the machine mode that bounds have. */
#define BNDmode (ix86_pmode == PMODE_DI ? BND64mode : BND32mode)
diff --git a/gcc/config/i386/i386.md b/gcc/config/i386/i386.md
index c08e4f55cff..c563a26cd60 100644
--- a/gcc/config/i386/i386.md
+++ b/gcc/config/i386/i386.md
@@ -18375,6 +18375,42 @@
"* return output_probe_stack_range (operands[0], operands[2]);"
[(set_attr "type" "multi")])
+;; Non-local goto support.
+
+(define_expand "save_stack_nonlocal"
+ [(use (match_operand 0 "memory_operand" ""))
+ (use (match_operand 1 "register_operand" ""))]
+ ""
+{
+ /* Stack is saved in ptr_mode and stack register is in Pmode. */
+ if (GET_MODE (operands[0]) != GET_MODE (operands[1]))
+ {
+ if (GET_MODE (operands[0]) != ptr_mode
+ || GET_MODE (operands[1]) != Pmode)
+ gcc_unreachable ();
+ operands[1] = gen_rtx_SUBREG (ptr_mode, operands[1], 0);
+ }
+ emit_move_insn (operands[0], operands[1]);
+ DONE;
+})
+
+(define_expand "restore_stack_nonlocal"
+ [(use (match_operand 0 "register_operand" ""))
+ (use (match_operand 1 "memory_operand" ""))]
+ ""
+{
+ /* Stack is saved in ptr_mode and stack register is in Pmode. */
+ if (GET_MODE (operands[0]) != GET_MODE (operands[1]))
+ {
+ if (GET_MODE (operands[0]) != Pmode
+ || GET_MODE (operands[1]) != ptr_mode)
+ gcc_unreachable ();
+ operands[1] = gen_rtx_ZERO_EXTEND (Pmode, operands[1]);
+ }
+ emit_move_insn (operands[0], operands[1]);
+ DONE;
+})
+
/* Additional processing for builtin_setjmp. Store the shadow stack pointer
as a forth element in jmpbuf. */
(define_expand "builtin_setjmp_setup"
diff --git a/gcc/testsuite/gcc.dg/pr84150.c b/gcc/testsuite/gcc.dg/pr84150.c
new file mode 100644
index 00000000000..1e7a04c1e9c
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr84150.c
@@ -0,0 +1,45 @@
+/* { dg-do run } */
+/* { dg-options "-O" } */
+/* { dg-require-effective-target indirect_jumps } */
+
+void *buf[6] = {
+ (void *) -1,
+ (void *) -1,
+ (void *) -1,
+ (void *) -1,
+ (void *) -1,
+ (void *) -1
+};
+
+void raise0(void)
+{
+ __builtin_longjmp (buf, 1);
+}
+
+int execute(int cmd)
+{
+ int last = 0;
+
+ if (__builtin_setjmp (buf) == 0)
+ while (1)
+ {
+ last = 1;
+ raise0 ();
+ }
+
+ if (last == 0)
+ return 0;
+ else
+ return cmd;
+}
+
+int main(void)
+{
+ if (execute (1) == 0)
+ __builtin_abort ();
+
+ if (buf[5] != (void *) -1)
+ __builtin_abort ();
+
+ return 0;
+}
diff --git a/gcc/testsuite/gcc.target/i386/pr84150.c
b/gcc/testsuite/gcc.target/i386/pr84150.c
new file mode 100644
index 00000000000..11d3d361487
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr84150.c
@@ -0,0 +1,44 @@
+/* { dg-do run { target x32 } } */
+/* { dg-options "-O -maddress-mode=long" } */
+
+void *buf[6] = {
+ (void *) -1,
+ (void *) -1,
+ (void *) -1,
+ (void *) -1,
+ (void *) -1,
+ (void *) -1
+};
+
+void raise0(void)
+{
+ __builtin_longjmp (buf, 1);
+}
+
+int execute(int cmd)
+{
+ int last = 0;
+
+ if (__builtin_setjmp (buf) == 0)
+ while (1)
+ {
+ last = 1;
+ raise0 ();
+ }
+
+ if (last == 0)
+ return 0;
+ else
+ return cmd;
+}
+
+int main(void)
+{
+ if (execute (1) == 0)
+ __builtin_abort ();
+
+ if (buf[5] != (void *) -1)
+ __builtin_abort ();
+
+ return 0;
+}
--
2.14.3
