[gcc r14-5830] i386: Fix ICE with -fsplit-stack -mcmodel=large [PR112686]

[Uros Bizjak <uros@gcc.gnu.org>]

https://gcc.gnu.org/g:404ea4c1381398aee162415a88e5cb81c44f8c69

commit r14-5830-g404ea4c1381398aee162415a88e5cb81c44f8c69
Author: Uros Bizjak <ubizjak@gmail.com>
Date:   Fri Nov 24 16:11:27 2023 +0100

    i386: Fix ICE with -fsplit-stack -mcmodel=large [PR112686]
    
    For -mcmodel=large, we have to load function address to a register.
    
            PR target/112686
    
    gcc/ChangeLog:
    
            * config/i386/i386.cc (ix86_expand_split_stack_prologue): Load
            function address to a register for ix86_cmodel == CM_LARGE.
    
    gcc/testsuite/ChangeLog:
    
            * gcc.target/i386/pr112686.c: New test.

Diff:
---
 gcc/config/i386/i386.cc                  | 9 +++++----
 gcc/testsuite/gcc.target/i386/pr112686.c | 5 +++++
 2 files changed, 10 insertions(+), 4 deletions(-)

diff --git a/gcc/config/i386/i386.cc b/gcc/config/i386/i386.cc
index 7b922857d80..9390f525b99 100644
--- a/gcc/config/i386/i386.cc
+++ b/gcc/config/i386/i386.cc
@@ -10481,6 +10481,8 @@ ix86_expand_split_stack_prologue (void)
 	      SYMBOL_REF_FLAGS (split_stack_fn_large) |= SYMBOL_FLAG_LOCAL;
 	    }
 
+	  fn = split_stack_fn_large;
+
 	  if (ix86_cmodel == CM_LARGE_PIC)
 	    {
 	      rtx_code_label *label;
@@ -10494,16 +10496,15 @@ ix86_expand_split_stack_prologue (void)
 	      emit_insn (gen_set_rip_rex64 (reg10, label));
 	      emit_insn (gen_set_got_offset_rex64 (reg11, label));
 	      emit_insn (gen_add2_insn (reg10, reg11));
-	      x = gen_rtx_UNSPEC (Pmode, gen_rtvec (1, split_stack_fn_large),
-				  UNSPEC_GOT);
+	      x = gen_rtx_UNSPEC (Pmode, gen_rtvec (1, fn), UNSPEC_GOT);
 	      x = gen_rtx_CONST (Pmode, x);
 	      emit_move_insn (reg11, x);
 	      x = gen_rtx_PLUS (Pmode, reg10, reg11);
 	      x = gen_const_mem (Pmode, x);
 	      fn = copy_to_suggested_reg (x, reg11, Pmode);
 	    }
-	  else
-	    fn = split_stack_fn_large;
+	  else if (ix86_cmodel == CM_LARGE)
+	    fn = copy_to_suggested_reg (fn, reg11, Pmode);
 
 	  /* When using the large model we need to load the address
 	     into a register, and we've run out of registers.  So we
diff --git a/gcc/testsuite/gcc.target/i386/pr112686.c b/gcc/testsuite/gcc.target/i386/pr112686.c
new file mode 100644
index 00000000000..858e91ba727
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr112686.c
@@ -0,0 +1,5 @@
+/* PR target/112686 */
+/* { dg-do compile { target lp64 } } */
+/* { dg-options "-fsplit-stack -mcmodel=large" } */
+
+void foo (void) {}