[PATCH v2 2/3] LoongArch: Fix ICE on atomic-compare-exchange-5.c

[Xi Ruoyao]

Fix the ICE:

../gcc/gcc/testsuite/gcc.dg/atomic-compare-exchange-5.c:88:1: internal compiler 
error: output_operand: invalid use of '%t'
   88 | }
      | ^

The ICE is because we have an incorrect condition
"GET_MODE (op) != TImode": we may use (const_int 0) here but it is in
VOIDmode.

Use reg_or_0_operand instead of hand-written (and incorrect) logic to
fix it.

gcc/ChangeLog:

        * config/loongarch/loongarch.cc (loongarch_print_operand): Call
        reg_or_0_operand for checking the sanity of for %t.
---
 gcc/config/loongarch/loongarch.cc | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/gcc/config/loongarch/loongarch.cc 
b/gcc/config/loongarch/loongarch.cc
index 0935d7ba092..ef5d5f4e060 100644
--- a/gcc/config/loongarch/loongarch.cc
+++ b/gcc/config/loongarch/loongarch.cc
@@ -6495,8 +6495,7 @@ loongarch_print_operand (FILE *file, rtx op, int letter)
       break;
 
     case 't':
-      if (GET_MODE (op) != TImode
-         || (op != CONST0_RTX (TImode) && code != REG))
+      if (!reg_or_0_operand (op, TImode))
        {
          output_operand_lossage ("invalid use of '%%%c'", letter);
          break;
-- 
2.51.0