[Bug target/65167] ICE: in assign_by_spills, at lra-assigns.c:1383 (unable to find a register to spill) with -O -fschedule-insns -fcheck-pointer-bounds -mmpx

[enkovich.gnu at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65167

--- Comment #4 from Ilya Enkovich <enkovich.gnu at gmail dot com> ---
ix86_function_arg_regno_p doesn't recognize bnd registers as args. Also
avoid_func_arg_motion doesn't work for BNDSTX because it is not a single set.  

This patch works for reproducer:

diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
index 71a5b22..acbe25f 100644
--- a/gcc/config/i386/i386.c
+++ b/gcc/config/i386/i386.c
@@ -6068,6 +6068,9 @@ ix86_function_arg_regno_p (int regno)
   int i;
   const int *parm_regs;

+  if (TARGET_MPX && BND_REGNO_P (regno))
+    return true;
+
   if (!TARGET_64BIT)
     {
       if (TARGET_MACHO)
@@ -26846,6 +26849,16 @@ avoid_func_arg_motion (rtx_insn *first_arg, rtx_insn
*insn)
   rtx set;
   rtx tmp;

+  /* Add anti dependencies for bounds stores.  */
+  if (INSN_P (insn)
+      && GET_CODE (PATTERN (insn)) == PARALLEL
+      && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == UNSPEC
+      && XINT (XVECEXP (PATTERN (insn), 0, 0), 1) == UNSPEC_BNDSTX)
+    {
+      add_dependence (first_arg, insn, REG_DEP_ANTI);
+      return;
+    }
+
   set = single_set (insn);
   if (!set)
     return;


Will run a testing for it.