With the above two options, use a temporary register regno (as returned
from split_stack_prologue_scratch_regno) as an indirect call scratch
register to hold __morestack function address. On 64-bit targets, two
temporary registers are always available, so load the function address in
%r11 and call __morestack_large_model with its one-argument-register value
in %r10. On 32-bit targets, bail out with a "sorry" if the temporary
register can not be obtained.
On 32-bit targets, also emit a PIC sequence that re-uses the obtained indirect
call scratch register before moving the function address to it. We can
not set up %ebx PIC register in this case, but __morestack is prepared
for this situation and sets it up by itself.
PR target/89316
gcc/ChangeLog:
* config/i386/i386.cc (ix86_expand_split_stack_prologue): Obtain
scratch regno when flag_force_indirect_call is set. On 64-bit
targets, call __morestack_large_model when flag_force_indirect_call
is set and on 32-bit targets with -fpic, manually expand PIC sequence
to call __morestack. Move the function address to an indirect
call scratch register.
gcc/testsuite/ChangeLog:
* g++.target/i386/pr89316.C: New test.
* gcc.target/i386/pr112605-1.c: New test.
* gcc.target/i386/pr112605-2.c: New test.
* gcc.target/i386/pr112605.c: New test.
Jakub, I'm not entirely sure x86_32 PIC sequence is 100% correct
(please note that the missing %ebx setup situation is handled in
__morestack), so I'd be very grateful for your review of this part.
Uros.
diff --git a/gcc/config/i386/i386.cc b/gcc/config/i386/i386.cc
index 683ac643bc8..a37f683d895 100644
--- a/gcc/config/i386/i386.cc
+++ b/gcc/config/i386/i386.cc
@@ -10353,6 +10353,7 @@ ix86_expand_split_stack_prologue (void)
rtx_code_label *label;
rtx limit, current, allocate_rtx, call_fusage;
rtx_insn *call_insn;
+ unsigned int scratch_regno = INVALID_REGNUM;
rtx scratch_reg = NULL_RTX;
rtx_code_label *varargs_label = NULL;
rtx fn;
@@ -10375,11 +10376,16 @@ ix86_expand_split_stack_prologue (void)
limit = ix86_split_stack_guard ();
- if (allocate < SPLIT_STACK_AVAILABLE)
- current = stack_pointer_rtx;
- else
+ if (allocate >= SPLIT_STACK_AVAILABLE
+ || flag_force_indirect_call)
+ {
+ scratch_regno = split_stack_prologue_scratch_regno ();
+ if (scratch_regno == INVALID_REGNUM)
+ return;
+ }
+
+ if (allocate >= SPLIT_STACK_AVAILABLE)
{
- unsigned int scratch_regno;
rtx offset;
/* We need a scratch register to hold the stack pointer minus
@@ -10387,9 +10393,7 @@ ix86_expand_split_stack_prologue (void)
function, the scratch register can be any caller-saved
register which is not used for parameters. */
offset = GEN_INT (- allocate);
- scratch_regno = split_stack_prologue_scratch_regno ();
- if (scratch_regno == INVALID_REGNUM)
- return;
+
scratch_reg = gen_rtx_REG (Pmode, scratch_regno);
if (!TARGET_64BIT || x86_64_immediate_operand (offset, Pmode))
{
@@ -10407,6 +10411,8 @@ ix86_expand_split_stack_prologue (void)
}
current = scratch_reg;
}
+ else
+ current = stack_pointer_rtx;
ix86_expand_branch (GEU, current, limit, label);
rtx_insn *jump_insn = get_last_insn ();
@@ -10435,8 +10441,8 @@ ix86_expand_split_stack_prologue (void)
{
rtx reg10, reg11;
- reg10 = gen_rtx_REG (Pmode, R10_REG);
- reg11 = gen_rtx_REG (Pmode, R11_REG);
+ reg10 = gen_rtx_REG (DImode, R10_REG);
+ reg11 = gen_rtx_REG (DImode, R11_REG);
/* If this function uses a static chain, it will be in %r10.
Preserve it across the call to __morestack. */
@@ -10449,32 +10455,25 @@ ix86_expand_split_stack_prologue (void)
use_reg (&call_fusage, rax);
}
- if ((ix86_cmodel == CM_LARGE || ix86_cmodel == CM_LARGE_PIC)
- && !TARGET_PECOFF)
+ if (flag_force_indirect_call
+ || ix86_cmodel == CM_LARGE || ix86_cmodel == CM_LARGE_PIC)
{
HOST_WIDE_INT argval;
- gcc_assert (Pmode == DImode);
- /* When using the large model we need to load the address
- into a register, and we've run out of registers. So we
- switch to a different calling convention, and we call a
- different function: __morestack_large. We pass the
- argument size in the upper 32 bits of r10 and pass the
- frame size in the lower 32 bits. */
- gcc_assert ((allocate & HOST_WIDE_INT_C (0xffffffff)) == allocate);
- gcc_assert ((args_size & 0xffffffff) == args_size);
-
if (split_stack_fn_large == NULL_RTX)
{
split_stack_fn_large
= gen_rtx_SYMBOL_REF (Pmode, "__morestack_large_model");
SYMBOL_REF_FLAGS (split_stack_fn_large) |= SYMBOL_FLAG_LOCAL;
}
+
if (ix86_cmodel == CM_LARGE_PIC)
{
rtx_code_label *label;
rtx x;
+ gcc_assert (Pmode == DImode);
+
label = gen_label_rtx ();
emit_label (label);
LABEL_PRESERVE_P (label) = 1;
@@ -10487,12 +10486,19 @@ ix86_expand_split_stack_prologue (void)
emit_move_insn (reg11, x);
x = gen_rtx_PLUS (Pmode, reg10, reg11);
x = gen_const_mem (Pmode, x);
- emit_move_insn (reg11, x);
+ fn = copy_to_suggested_reg (x, reg11, Pmode);
}
else
- emit_move_insn (reg11, split_stack_fn_large);
+ fn = split_stack_fn_large;
- fn = reg11;
+ /* When using the large model we need to load the address
+ into a register, and we've run out of registers. So we
+ switch to a different calling convention, and we call a
+ different function: __morestack_large. We pass the
+ argument size in the upper 32 bits of r10 and pass the
+ frame size in the lower 32 bits. */
+ gcc_assert ((allocate & HOST_WIDE_INT_C (0xffffffff)) == allocate);
+ gcc_assert ((args_size & 0xffffffff) == args_size);
argval = ((args_size << 16) << 16) + allocate;
emit_move_insn (reg10, GEN_INT (argval));
@@ -10508,12 +10514,40 @@ ix86_expand_split_stack_prologue (void)
}
else
{
+ if (flag_force_indirect_call && flag_pic)
+ {
+ rtx x;
+
+ gcc_assert (Pmode == SImode);
+
+ scratch_reg = gen_rtx_REG (Pmode, scratch_regno);
+
+ emit_insn (gen_set_got (scratch_reg));
+ x = gen_rtx_UNSPEC (Pmode, gen_rtvec (1, split_stack_fn),
+ UNSPEC_GOT);
+ x = gen_rtx_CONST (Pmode, x);
+ x = gen_rtx_PLUS (Pmode, scratch_reg, x);
+ x = gen_const_mem (Pmode, x);
+ fn = copy_to_suggested_reg (x, scratch_reg, Pmode);
+ }
+
rtx_insn *insn = emit_insn (gen_push (GEN_INT (args_size)));
add_reg_note (insn, REG_ARGS_SIZE, GEN_INT (UNITS_PER_WORD));
insn = emit_insn (gen_push (allocate_rtx));
add_reg_note (insn, REG_ARGS_SIZE, GEN_INT (2 * UNITS_PER_WORD));
pop = GEN_INT (2 * UNITS_PER_WORD);
}
+
+ if (flag_force_indirect_call && !register_operand (fn, VOIDmode))
+ {
+ scratch_reg = gen_rtx_REG (word_mode, scratch_regno);
+
+ if (GET_MODE (fn) != word_mode)
+ fn = gen_rtx_ZERO_EXTEND (word_mode, fn);
+
+ fn = copy_to_suggested_reg (fn, scratch_reg, word_mode);
+ }
+
call_insn = ix86_expand_call (NULL_RTX, gen_rtx_MEM (QImode, fn),
GEN_INT (UNITS_PER_WORD), constm1_rtx,
pop, false);
@@ -10558,7 +10592,6 @@ ix86_expand_split_stack_prologue (void)
slot. */
if (cfun->machine->split_stack_varargs_pointer != NULL_RTX)
{
- unsigned int scratch_regno;
rtx frame_reg;
int words;
diff --git a/gcc/testsuite/g++.target/i386/pr89316.C
b/gcc/testsuite/g++.target/i386/pr89316.C
new file mode 100644
index 00000000000..2f05ef751a5
--- /dev/null
+++ b/gcc/testsuite/g++.target/i386/pr89316.C
@@ -0,0 +1,6 @@
+// PR target/89316
+// { dg-do compile }
+// { dg-require-effective-target split_stack }
+// { dg-options "-fsplit-stack -mforce-indirect-call" }
+
+struct foo { foo (); } foobar;
diff --git a/gcc/testsuite/gcc.target/i386/pr112605-1.c
b/gcc/testsuite/gcc.target/i386/pr112605-1.c
new file mode 100644
index 00000000000..57b91909f0c
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr112605-1.c
@@ -0,0 +1,7 @@
+/* PR target/112605 */
+/* { dg-do compile } */
+/* { dg-require-effective-target split_stack } */
+/* { dg-require-effective-target fpic } */
+/* { dg-options "-fsplit-stack -fpic -mforce-indirect-call" } */
+
+#include "pr112605.c"
diff --git a/gcc/testsuite/gcc.target/i386/pr112605-2.c
b/gcc/testsuite/gcc.target/i386/pr112605-2.c
new file mode 100644
index 00000000000..7db9aba3abc
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr112605-2.c
@@ -0,0 +1,7 @@
+/* PR target/112605 */
+/* { dg-do compile { target lp64 } } */
+/* { dg-require-effective-target split_stack } */
+/* { dg-require-effective-target fpic } */
+/* { dg-options "-fsplit-stack -fpic -mcmodel=large -mforce-indirect-call " }
*/
+
+#include "pr112605.c"
diff --git a/gcc/testsuite/gcc.target/i386/pr112605.c
b/gcc/testsuite/gcc.target/i386/pr112605.c
new file mode 100644
index 00000000000..da50a0f6d94
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr112605.c
@@ -0,0 +1,24 @@
+/* PR target/112605 */
+/* { dg-do compile } */
+/* { dg-require-effective-target split_stack } */
+/* { dg-options "-fsplit-stack -mforce-indirect-call" } */
+
+int x;
+int y;
+
+void __attribute__((noinline)) f1(void)
+{
+ x++;
+}
+
+static __attribute__((noinline)) void f3(void)
+{
+ y++;
+}
+
+void f2()
+{
+ f1();
+ f3();
+ f1();
+}
